Merge tag 'tty-3.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial driver patches from Greg KH:
 "Here's the big tty/serial driver pull request for 3.12-rc1.

  Lots of n_tty reworks to resolve some very long-standing issues,
  removing the 3-4 different locks that were taken for every character.
  This code has been beaten on for a long time in linux-next with no
  reported regressions.

  Other than that, a range of serial and tty driver updates and
  revisions.  Full details in the shortlog"

* tag 'tty-3.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (226 commits)
  hvc_xen: Remove unnecessary __GFP_ZERO from kzalloc
  serial: imx: initialize the local variable
  tty: ar933x_uart: add device tree support and binding documentation
  tty: ar933x_uart: allow to build the driver as a module
  ARM: dts: msm: Update uartdm compatible strings
  devicetree: serial: Document msm_serial bindings
  serial: unify serial bindings into a single dir
  serial: fsl-imx-uart: Cleanup duplicate device tree binding
  tty: ar933x_uart: use config_enabled() macro to clean up ifdefs
  tty: ar933x_uart: remove superfluous assignment of ar933x_uart_driver.nr
  tty: ar933x_uart: use the clk API to get the uart clock
  tty: serial: cpm_uart: Adding proper request of GPIO used by cpm_uart driver
  serial: sirf: fix the amount of serial ports
  serial: sirf: define macro for some magic numbers of USP
  serial: icom: move array overflow checks earlier
  TTY: amiserial, remove unnecessary platform_set_drvdata()
  serial: st-asc: remove unnecessary platform_set_drvdata()
  msm_serial: Send more than 1 character on the console w/ UARTDM
  msm_serial: Add support for non-GSBI UARTDM devices
  msm_serial: Switch clock consumer strings and simplify code
  ...

83 files changed, 6454 insertions, 2922 deletions

diff --git a/drivers/net/irda/irtty-sir.c b/drivers/net/irda/irtty-sir.c
index a4126719783..177441afeb9 100644
--- a/drivers/net/irda/irtty-sir.c
+++ b/drivers/net/irda/irtty-sir.c
@@ -123,14 +123,14 @@ static int irtty_change_speed(struct sir_dev *dev, unsigned speed)
 
 	tty = priv->tty;
 
-	mutex_lock(&tty->termios_mutex);
+	down_write(&tty->termios_rwsem);
 	old_termios = tty->termios;
 	cflag = tty->termios.c_cflag;
 	tty_encode_baud_rate(tty, speed, speed);
 	if (tty->ops->set_termios)
 		tty->ops->set_termios(tty, &old_termios);
 	priv->io.speed = speed;
-	mutex_unlock(&tty->termios_mutex);
+	up_write(&tty->termios_rwsem);
 
 	return 0;
 }
@@ -280,7 +280,7 @@ static inline void irtty_stop_receiver(struct tty_struct *tty, int stop)
 	struct ktermios old_termios;
 	int cflag;
 
-	mutex_lock(&tty->termios_mutex);
+	down_write(&tty->termios_rwsem);
 	old_termios = tty->termios;
 	cflag = tty->termios.c_cflag;
 	
@@ -292,7 +292,7 @@ static inline void irtty_stop_receiver(struct tty_struct *tty, int stop)
 	tty->termios.c_cflag = cflag;
 	if (tty->ops->set_termios)
 		tty->ops->set_termios(tty, &old_termios);
-	mutex_unlock(&tty->termios_mutex);
+	up_write(&tty->termios_rwsem);
 }
 
 /*****************************************************************/
diff --git a/drivers/of/base.c b/drivers/of/base.c
index 5c5427918eb..1c3c79c7974 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -32,6 +32,7 @@ struct device_node *of_allnodes;
 EXPORT_SYMBOL(of_allnodes);
 struct device_node *of_chosen;
 struct device_node *of_aliases;
+static struct device_node *of_stdout;
 
 DEFINE_MUTEX(of_aliases_mutex);
 
@@ -1595,6 +1596,15 @@ void of_alias_scan(void * (*dt_alloc)(u64 size, u64 align))
 	of_chosen = of_find_node_by_path("/chosen");
 	if (of_chosen == NULL)
 		of_chosen = of_find_node_by_path("/chosen@0");
+
+	if (of_chosen) {
+		const char *name;
+
+		name = of_get_property(of_chosen, "linux,stdout-path", NULL);
+		if (name)
+			of_stdout = of_find_node_by_path(name);
+	}
+
 	of_aliases = of_find_node_by_path("/aliases");
 	if (!of_aliases)
 		return;
@@ -1703,3 +1713,19 @@ const char *of_prop_next_string(struct property *prop, const char *cur)
 	return curv;
 }
 EXPORT_SYMBOL_GPL(of_prop_next_string);
+
+/**
+ * of_device_is_stdout_path - check if a device node matches the
+ *                            linux,stdout-path property
+ *
+ * Check if this device node matches the linux,stdout-path property
+ * in the chosen node. return true if yes, false otherwise.
+ */
+int of_device_is_stdout_path(struct device_node *dn)
+{
+	if (!of_stdout)
+		return false;
+
+	return of_stdout == dn;
+}
+EXPORT_SYMBOL_GPL(of_device_is_stdout_path);
diff --git a/drivers/staging/comedi/comedidev.h b/drivers/staging/comedi/comedidev.h
index f2f75b9dfb8..2e19f659cd2 100644
--- a/drivers/staging/comedi/comedidev.h
+++ b/drivers/staging/comedi/comedidev.h
@@ -390,7 +390,6 @@ void comedi_driver_unregister(struct comedi_driver *);
  */
 #define PCI_VENDOR_ID_KOLTER		0x1001
 #define PCI_VENDOR_ID_ICP		0x104c
-#define PCI_VENDOR_ID_AMCC		0x10e8
 #define PCI_VENDOR_ID_DT		0x1116
 #define PCI_VENDOR_ID_IOTECH		0x1616
 #define PCI_VENDOR_ID_CONTEC		0x1221
diff --git a/drivers/staging/dgrp/dgrp_tty.c b/drivers/staging/dgrp/dgrp_tty.c
index 654f6010b47..0d52de3729c 100644
--- a/drivers/staging/dgrp/dgrp_tty.c
+++ b/drivers/staging/dgrp/dgrp_tty.c
@@ -1120,7 +1120,9 @@ static void dgrp_tty_close(struct tty_struct *tty, struct file *file)
 				if (!sent_printer_offstr)
 					dgrp_tty_flush_buffer(tty);
 
+				spin_unlock_irqrestore(&nd->nd_lock, lock_flags);
 				tty_ldisc_flush(tty);
+				spin_lock_irqsave(&nd->nd_lock, lock_flags);
 				break;
 		}
 
diff --git a/drivers/tty/amiserial.c b/drivers/tty/amiserial.c
index 083710e0236..2b86f8e0fb5 100644
--- a/drivers/tty/amiserial.c
+++ b/drivers/tty/amiserial.c
@@ -1785,8 +1785,6 @@ static int __exit amiga_serial_remove(struct platform_device *pdev)
 	free_irq(IRQ_AMIGA_TBE, state);
 	free_irq(IRQ_AMIGA_RBF, state);
 
-	platform_set_drvdata(pdev, NULL);
-
 	return error;
 }
 
diff --git a/drivers/tty/hvc/hvc_console.c b/drivers/tty/hvc/hvc_console.c
index eb255e807c0..9eba119bcdd 100644
--- a/drivers/tty/hvc/hvc_console.c
+++ b/drivers/tty/hvc/hvc_console.c
@@ -361,7 +361,12 @@ static int hvc_open(struct tty_struct *tty, struct file * filp)
 		tty->driver_data = NULL;
 		tty_port_put(&hp->port);
 		printk(KERN_ERR "hvc_open: request_irq failed with rc %d.\n", rc);
-	}
+	} else
+		/* We are ready... raise DTR/RTS */
+		if (C_BAUD(tty))
+			if (hp->ops->dtr_rts)
+				hp->ops->dtr_rts(hp, 1);
+
 	/* Force wakeup of the polling thread */
 	hvc_kick();
 
@@ -393,6 +398,10 @@ static void hvc_close(struct tty_struct *tty, struct file * filp)
 		/* We are done with the tty pointer now. */
 		tty_port_tty_set(&hp->port, NULL);
 
+		if (C_HUPCL(tty))
+			if (hp->ops->dtr_rts)
+				hp->ops->dtr_rts(hp, 0);
+
 		if (hp->ops->notifier_del)
 			hp->ops->notifier_del(hp, hp->data);
 
diff --git a/drivers/tty/hvc/hvc_console.h b/drivers/tty/hvc/hvc_console.h
index 674d23cb919..91310198082 100644
--- a/drivers/tty/hvc/hvc_console.h
+++ b/drivers/tty/hvc/hvc_console.h
@@ -75,6 +75,9 @@ struct hv_ops {
 	/* tiocmget/set implementation */
 	int (*tiocmget)(struct hvc_struct *hp);
 	int (*tiocmset)(struct hvc_struct *hp, unsigned int set, unsigned int clear);
+
+	/* Callbacks to handle tty ports */
+	void (*dtr_rts)(struct hvc_struct *hp, int raise);
 };
 
 /* Register a vterm and a slot index for use as a console (console_init) */
diff --git a/drivers/tty/hvc/hvc_iucv.c b/drivers/tty/hvc/hvc_iucv.c
index 9d47f50c275..fd17a9b804b 100644
--- a/drivers/tty/hvc/hvc_iucv.c
+++ b/drivers/tty/hvc/hvc_iucv.c
@@ -656,21 +656,64 @@ static void hvc_iucv_notifier_hangup(struct hvc_struct *hp, int id)
 }
 
 /**
+ * hvc_iucv_dtr_rts() - HVC notifier for handling DTR/RTS
+ * @hp:		Pointer the HVC device (struct hvc_struct)
+ * @raise:	Non-zero to raise or zero to lower DTR/RTS lines
+ *
+ * This routine notifies the HVC back-end to raise or lower DTR/RTS
+ * lines.  Raising DTR/RTS is ignored.  Lowering DTR/RTS indicates to
+ * drop the IUCV connection (similar to hang up the modem).
+ */
+static void hvc_iucv_dtr_rts(struct hvc_struct *hp, int raise)
+{
+	struct hvc_iucv_private *priv;
+	struct iucv_path        *path;
+
+	/* Raising the DTR/RTS is ignored as IUCV connections can be
+	 * established at any times.
+	 */
+	if (raise)
+		return;
+
+	priv = hvc_iucv_get_private(hp->vtermno);
+	if (!priv)
+		return;
+
+	/* Lowering the DTR/RTS lines disconnects an established IUCV
+	 * connection.
+	 */
+	flush_sndbuf_sync(priv);
+
+	spin_lock_bh(&priv->lock);
+	path = priv->path;		/* save reference to IUCV path */
+	priv->path = NULL;
+	priv->iucv_state = IUCV_DISCONN;
+	spin_unlock_bh(&priv->lock);
+
+	/* Sever IUCV path outside of priv->lock due to lock ordering of:
+	 * priv->lock <--> iucv_table_lock */
+	if (path) {
+		iucv_path_sever(path, NULL);
+		iucv_path_free(path);
+	}
+}
+
+/**
  * hvc_iucv_notifier_del() - HVC notifier for closing a TTY for the last time.
  * @hp:		Pointer to the HVC device (struct hvc_struct)
  * @id:		Additional data (originally passed to hvc_alloc):
  *		the index of an struct hvc_iucv_private instance.
  *
  * This routine notifies the HVC back-end that the last tty device fd has been
- * closed.  The function calls hvc_iucv_cleanup() to clean up the struct
- * hvc_iucv_private instance.
+ * closed.  The function cleans up tty resources.  The clean-up of the IUCV
+ * connection is done in hvc_iucv_dtr_rts() and depends on the HUPCL termios
+ * control setting.
  *
  * Locking:	struct hvc_iucv_private->lock
  */
 static void hvc_iucv_notifier_del(struct hvc_struct *hp, int id)
 {
 	struct hvc_iucv_private *priv;
-	struct iucv_path	*path;
 
 	priv = hvc_iucv_get_private(id);
 	if (!priv)
@@ -679,17 +722,11 @@ static void hvc_iucv_notifier_del(struct hvc_struct *hp, int id)
 	flush_sndbuf_sync(priv);
 
 	spin_lock_bh(&priv->lock);
-	path = priv->path;		/* save reference to IUCV path */
-	priv->path = NULL;
-	hvc_iucv_cleanup(priv);
+	destroy_tty_buffer_list(&priv->tty_outqueue);
+	destroy_tty_buffer_list(&priv->tty_inqueue);
+	priv->tty_state = TTY_CLOSED;
+	priv->sndbuf_len = 0;
 	spin_unlock_bh(&priv->lock);
-
-	/* sever IUCV path outside of priv->lock due to lock ordering of:
-	 * priv->lock <--> iucv_table_lock */
-	if (path) {
-		iucv_path_sever(path, NULL);
-		iucv_path_free(path);
-	}
 }
 
 /**
@@ -931,6 +968,7 @@ static const struct hv_ops hvc_iucv_ops = {
 	.notifier_add = hvc_iucv_notifier_add,
 	.notifier_del = hvc_iucv_notifier_del,
 	.notifier_hangup = hvc_iucv_notifier_hangup,
+	.dtr_rts = hvc_iucv_dtr_rts,
 };
 
 /* Suspend / resume device operations */
diff --git a/drivers/tty/hvc/hvc_xen.c b/drivers/tty/hvc/hvc_xen.c
index 682210d778b..e61c36cbb86 100644
--- a/drivers/tty/hvc/hvc_xen.c
+++ b/drivers/tty/hvc/hvc_xen.c
@@ -208,7 +208,7 @@ static int xen_hvm_console_init(void)
 
 	info = vtermno_to_xencons(HVC_COOKIE);
 	if (!info) {
-		info = kzalloc(sizeof(struct xencons_info), GFP_KERNEL | __GFP_ZERO);
+		info = kzalloc(sizeof(struct xencons_info), GFP_KERNEL);
 		if (!info)
 			return -ENOMEM;
 	} else if (info->intf != NULL) {
@@ -257,7 +257,7 @@ static int xen_pv_console_init(void)
 
 	info = vtermno_to_xencons(HVC_COOKIE);
 	if (!info) {
-		info = kzalloc(sizeof(struct xencons_info), GFP_KERNEL | __GFP_ZERO);
+		info = kzalloc(sizeof(struct xencons_info), GFP_KERNEL);
 		if (!info)
 			return -ENOMEM;
 	} else if (info->intf != NULL) {
@@ -284,7 +284,7 @@ static int xen_initial_domain_console_init(void)
 
 	info = vtermno_to_xencons(HVC_COOKIE);
 	if (!info) {
-		info = kzalloc(sizeof(struct xencons_info), GFP_KERNEL | __GFP_ZERO);
+		info = kzalloc(sizeof(struct xencons_info), GFP_KERNEL);
 		if (!info)
 			return -ENOMEM;
 	}
diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c
index 642239015b4..c0f76da5530 100644
--- a/drivers/tty/n_gsm.c
+++ b/drivers/tty/n_gsm.c
@@ -807,7 +807,7 @@ static int gsm_dlci_data_output(struct gsm_mux *gsm, struct gsm_dlci *dlci)
 	int h = dlci->adaption - 1;
 
 	total_size = 0;
-	while(1) {
+	while (1) {
 		len = kfifo_len(dlci->fifo);
 		if (len == 0)
 			return total_size;
@@ -827,8 +827,8 @@ static int gsm_dlci_data_output(struct gsm_mux *gsm, struct gsm_dlci *dlci)
 		switch (dlci->adaption) {
 		case 1:	/* Unstructured */
 			break;
-		case 2:	/* Unstructed with modem bits. Always one byte as we never
-			   send inline break data */
+		case 2:	/* Unstructed with modem bits.
+		Always one byte as we never send inline break data */
 			*dp++ = gsm_encode_modem(dlci);
 			break;
 		}
@@ -968,7 +968,7 @@ static void gsm_dlci_data_kick(struct gsm_dlci *dlci)
 	unsigned long flags;
 	int sweep;
 
-	if (dlci->constipated) 
+	if (dlci->constipated)
 		return;
 
 	spin_lock_irqsave(&dlci->gsm->tx_lock, flags);
@@ -981,7 +981,7 @@ static void gsm_dlci_data_kick(struct gsm_dlci *dlci)
 			gsm_dlci_data_output(dlci->gsm, dlci);
 	}
 	if (sweep)
- 		gsm_dlci_data_sweep(dlci->gsm);
+		gsm_dlci_data_sweep(dlci->gsm);
 	spin_unlock_irqrestore(&dlci->gsm->tx_lock, flags);
 }
 
@@ -1138,7 +1138,7 @@ static void gsm_control_modem(struct gsm_mux *gsm, u8 *data, int clen)
 static void gsm_control_rls(struct gsm_mux *gsm, u8 *data, int clen)
 {
 	struct tty_port *port;
-	unsigned int addr = 0 ;
+	unsigned int addr = 0;
 	u8 bits;
 	int len = clen;
 	u8 *dp = data;
@@ -1740,10 +1740,11 @@ static void gsm_queue(struct gsm_mux *gsm)
 
 	if ((gsm->control & ~PF) == UI)
 		gsm->fcs = gsm_fcs_add_block(gsm->fcs, gsm->buf, gsm->len);
-	if (gsm->encoding == 0){
-		/* WARNING: gsm->received_fcs is used for gsm->encoding = 0 only.
-		            In this case it contain the last piece of data
-		            required to generate final CRC */
+	if (gsm->encoding == 0) {
+		/* WARNING: gsm->received_fcs is used for
+		gsm->encoding = 0 only.
+		In this case it contain the last piece of data
+		required to generate final CRC */
 		gsm->fcs = gsm_fcs_add(gsm->fcs, gsm->received_fcs);
 	}
 	if (gsm->fcs != GOOD_FCS) {
@@ -2904,9 +2905,11 @@ static int gsmtty_install(struct tty_driver *driver, struct tty_struct *tty)
 	gsm = gsm_mux[mux];
 	if (gsm->dead)
 		return -EL2HLT;
-	/* If DLCI 0 is not yet fully open return an error. This is ok from a locking
-	   perspective as we don't have to worry about this if DLCI0 is lost */
-	if (gsm->dlci[0] && gsm->dlci[0]->state != DLCI_OPEN) 
+	/* If DLCI 0 is not yet fully open return an error.
+	This is ok from a locking
+	perspective as we don't have to worry about this
+	if DLCI0 is lost */
+	if (gsm->dlci[0] && gsm->dlci[0]->state != DLCI_OPEN)
 		return -EL2NSYNC;
 	dlci = gsm->dlci[line];
 	if (dlci == NULL) {
diff --git a/drivers/tty/n_tty.c b/drivers/tty/n_tty.c
index 4bf0fc0843d..c9a9ddd1d0b 100644
--- a/drivers/tty/n_tty.c
+++ b/drivers/tty/n_tty.c
@@ -50,6 +50,7 @@
 #include <linux/uaccess.h>
 #include <linux/module.h>
 #include <linux/ratelimit.h>
+#include <linux/vmalloc.h>
 
 
 /* number of characters left in xmit buffer before select has we have room */
@@ -74,37 +75,81 @@
 #define ECHO_OP_SET_CANON_COL 0x81
 #define ECHO_OP_ERASE_TAB 0x82
 
+#define ECHO_COMMIT_WATERMARK	256
+#define ECHO_BLOCK		256
+#define ECHO_DISCARD_WATERMARK	N_TTY_BUF_SIZE - (ECHO_BLOCK + 32)
+
+
+#undef N_TTY_TRACE
+#ifdef N_TTY_TRACE
+# define n_tty_trace(f, args...)	trace_printk(f, ##args)
+#else
+# define n_tty_trace(f, args...)
+#endif
+
 struct n_tty_data {
-	unsigned int column;
+	/* producer-published */
+	size_t read_head;
+	size_t canon_head;
+	size_t echo_head;
+	size_t echo_commit;
+	DECLARE_BITMAP(char_map, 256);
+
+	/* private to n_tty_receive_overrun (single-threaded) */
 	unsigned long overrun_time;
 	int num_overrun;
 
+	/* non-atomic */
+	bool no_room;
+
+	/* must hold exclusive termios_rwsem to reset these */
 	unsigned char lnext:1, erasing:1, raw:1, real_raw:1, icanon:1;
-	unsigned char echo_overrun:1;
 
-	DECLARE_BITMAP(process_char_map, 256);
+	/* shared by producer and consumer */
+	char read_buf[N_TTY_BUF_SIZE];
 	DECLARE_BITMAP(read_flags, N_TTY_BUF_SIZE);
+	unsigned char echo_buf[N_TTY_BUF_SIZE];
 
-	char *read_buf;
-	int read_head;
-	int read_tail;
-	int read_cnt;
 	int minimum_to_wake;
 
-	unsigned char *echo_buf;
-	unsigned int echo_pos;
-	unsigned int echo_cnt;
+	/* consumer-published */
+	size_t read_tail;
+	size_t line_start;
 
-	int canon_data;
-	unsigned long canon_head;
+	/* protected by output lock */
+	unsigned int column;
 	unsigned int canon_column;
+	size_t echo_tail;
 
 	struct mutex atomic_read_lock;
 	struct mutex output_lock;
-	struct mutex echo_lock;
-	raw_spinlock_t read_lock;
 };
 
+static inline size_t read_cnt(struct n_tty_data *ldata)
+{
+	return ldata->read_head - ldata->read_tail;
+}
+
+static inline unsigned char read_buf(struct n_tty_data *ldata, size_t i)
+{
+	return ldata->read_buf[i & (N_TTY_BUF_SIZE - 1)];
+}
+
+static inline unsigned char *read_buf_addr(struct n_tty_data *ldata, size_t i)
+{
+	return &ldata->read_buf[i & (N_TTY_BUF_SIZE - 1)];
+}
+
+static inline unsigned char echo_buf(struct n_tty_data *ldata, size_t i)
+{
+	return ldata->echo_buf[i & (N_TTY_BUF_SIZE - 1)];
+}
+
+static inline unsigned char *echo_buf_addr(struct n_tty_data *ldata, size_t i)
+{
+	return &ldata->echo_buf[i & (N_TTY_BUF_SIZE - 1)];
+}
+
 static inline int tty_put_user(struct tty_struct *tty, unsigned char x,
 			       unsigned char __user *ptr)
 {
@@ -114,33 +159,18 @@ static inline int tty_put_user(struct tty_struct *tty, unsigned char x,
 	return put_user(x, ptr);
 }
 
-/**
- *	n_tty_set_room	-	receive space
- *	@tty: terminal
- *
- *	Updates tty->receive_room to reflect the currently available space
- *	in the input buffer, and re-schedules the flip buffer work if space
- *	just became available.
- *
- *	Locks: Concurrent update is protected with read_lock
- */
-
-static int set_room(struct tty_struct *tty)
+static int receive_room(struct tty_struct *tty)
 {
 	struct n_tty_data *ldata = tty->disc_data;
 	int left;
-	int old_left;
-	unsigned long flags;
-
-	raw_spin_lock_irqsave(&ldata->read_lock, flags);
 
 	if (I_PARMRK(tty)) {
 		/* Multiply read_cnt by 3, since each byte might take up to
 		 * three times as many spaces when PARMRK is set (depending on
 		 * its flags, e.g. parity error). */
-		left = N_TTY_BUF_SIZE - ldata->read_cnt * 3 - 1;
+		left = N_TTY_BUF_SIZE - read_cnt(ldata) * 3 - 1;
 	} else
-		left = N_TTY_BUF_SIZE - ldata->read_cnt - 1;
+		left = N_TTY_BUF_SIZE - read_cnt(ldata) - 1;
 
 	/*
 	 * If we are doing input canonicalization, and there are no
@@ -149,19 +179,31 @@ static int set_room(struct tty_struct *tty)
 	 * characters will be beeped.
 	 */
 	if (left <= 0)
-		left = ldata->icanon && !ldata->canon_data;
-	old_left = tty->receive_room;
-	tty->receive_room = left;
+		left = ldata->icanon && ldata->canon_head == ldata->read_tail;
 
-	raw_spin_unlock_irqrestore(&ldata->read_lock, flags);
-
-	return left && !old_left;
+	return left;
 }
 
+/**
+ *	n_tty_set_room	-	receive space
+ *	@tty: terminal
+ *
+ *	Re-schedules the flip buffer work if space just became available.
+ *
+ *	Caller holds exclusive termios_rwsem
+ *	   or
+ *	n_tty_read()/consumer path:
+ *		holds non-exclusive termios_rwsem
+ */
+
 static void n_tty_set_room(struct tty_struct *tty)
 {
+	struct n_tty_data *ldata = tty->disc_data;
+
 	/* Did this open up the receive buffer? We may need to flip */
-	if (set_room(tty)) {
+	if (unlikely(ldata->no_room) && receive_room(tty)) {
+		ldata->no_room = 0;
+
 		WARN_RATELIMIT(tty->port->itty == NULL,
 				"scheduling with invalid itty\n");
 		/* see if ldisc has been killed - if so, this means that
@@ -170,17 +212,93 @@ static void n_tty_set_room(struct tty_struct *tty)
 		 */
 		WARN_RATELIMIT(test_bit(TTY_LDISC_HALTED, &tty->flags),
 			       "scheduling buffer work for halted ldisc\n");
-		schedule_work(&tty->port->buf.work);
+		queue_work(system_unbound_wq, &tty->port->buf.work);
 	}
 }
 
-static void put_tty_queue_nolock(unsigned char c, struct n_tty_data *ldata)
+static ssize_t chars_in_buffer(struct tty_struct *tty)
+{
+	struct n_tty_data *ldata = tty->disc_data;
+	ssize_t n = 0;
+
+	if (!ldata->icanon)
+		n = read_cnt(ldata);
+	else
+		n = ldata->canon_head - ldata->read_tail;
+	return n;
+}
+
+/**
+ *	n_tty_write_wakeup	-	asynchronous I/O notifier
+ *	@tty: tty device
+ *
+ *	Required for the ptys, serial driver etc. since processes
+ *	that attach themselves to the master and rely on ASYNC
+ *	IO must be woken up
+ */
+
+static void n_tty_write_wakeup(struct tty_struct *tty)
 {
-	if (ldata->read_cnt < N_TTY_BUF_SIZE) {
-		ldata->read_buf[ldata->read_head] = c;
-		ldata->read_head = (ldata->read_head + 1) & (N_TTY_BUF_SIZE-1);
-		ldata->read_cnt++;
+	if (tty->fasync && test_and_clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags))
+		kill_fasync(&tty->fasync, SIGIO, POLL_OUT);
+}
+
+static void n_tty_check_throttle(struct tty_struct *tty)
+{
+	if (tty->driver->type == TTY_DRIVER_TYPE_PTY)
+		return;
+	/*
+	 * Check the remaining room for the input canonicalization
+	 * mode.  We don't want to throttle the driver if we're in
+	 * canonical mode and don't have a newline yet!
+	 */
+	while (1) {
+		int throttled;
+		tty_set_flow_change(tty, TTY_THROTTLE_SAFE);
+		if (receive_room(tty) >= TTY_THRESHOLD_THROTTLE)
+			break;
+		throttled = tty_throttle_safe(tty);
+		if (!throttled)
+			break;
+	}
+	__tty_set_flow_change(tty, 0);
+}
+
+static void n_tty_check_unthrottle(struct tty_struct *tty)
+{
+	if (tty->driver->type == TTY_DRIVER_TYPE_PTY &&
+	    tty->link->ldisc->ops->write_wakeup == n_tty_write_wakeup) {
+		if (chars_in_buffer(tty) > TTY_THRESHOLD_UNTHROTTLE)
+			return;
+		if (!tty->count)
+			return;
+		n_tty_set_room(tty);
+		n_tty_write_wakeup(tty->link);
+		wake_up_interruptible_poll(&tty->link->write_wait, POLLOUT);
+		return;
+	}
+
+	/* If there is enough space in the read buffer now, let the
+	 * low-level driver know. We use chars_in_buffer() to
+	 * check the buffer, as it now knows about canonical mode.
+	 * Otherwise, if the driver is throttled and the line is
+	 * longer than TTY_THRESHOLD_UNTHROTTLE in canonical mode,
+	 * we won't get any more characters.
+	 */
+
+	while (1) {
+		int unthrottled;
+		tty_set_flow_change(tty, TTY_UNTHROTTLE_SAFE);
+		if (chars_in_buffer(tty) > TTY_THRESHOLD_UNTHROTTLE)
+			break;
+		if (!tty->count)
+			break;
+		n_tty_set_room(tty);
+		unthrottled = tty_unthrottle_safe(tty);
+		if (!unthrottled)
+			break;
 	}
+	__tty_set_flow_change(tty, 0);
 }
 
 /**
@@ -188,21 +306,19 @@ static void put_tty_queue_nolock(unsigned char c, struct n_tty_data *ldata)
  *	@c: character
  *	@ldata: n_tty data
  *
- *	Add a character to the tty read_buf queue. This is done under the
- *	read_lock to serialize character addition and also to protect us
- *	against parallel reads or flushes
+ *	Add a character to the tty read_buf queue.
+ *
+ *	n_tty_receive_buf()/producer path:
+ *		caller holds non-exclusive termios_rwsem
+ *		modifies read_head
+ *
+ *	read_head is only considered 'published' if canonical mode is
+ *	not active.
  */
 
-static void put_tty_queue(unsigned char c, struct n_tty_data *ldata)
+static inline void put_tty_queue(unsigned char c, struct n_tty_data *ldata)
 {
-	unsigned long flags;
-	/*
-	 *	The problem of stomping on the buffers ends here.
-	 *	Why didn't anyone see this one coming? --AJK
-	*/
-	raw_spin_lock_irqsave(&ldata->read_lock, flags);
-	put_tty_queue_nolock(c, ldata);
-	raw_spin_unlock_irqrestore(&ldata->read_lock, flags);
+	*read_buf_addr(ldata, ldata->read_head++) = c;
 }
 
 /**
@@ -212,22 +328,17 @@ static void put_tty_queue(unsigned char c, struct n_tty_data *ldata)
  *	Reset the read buffer counters and clear the flags.
  *	Called from n_tty_open() and n_tty_flush_buffer().
  *
- *	Locking: tty_read_lock for read fields.
+ *	Locking: caller holds exclusive termios_rwsem
+ *		 (or locking is not required)
  */
 
 static void reset_buffer_flags(struct n_tty_data *ldata)
 {
-	unsigned long flags;
+	ldata->read_head = ldata->canon_head = ldata->read_tail = 0;
+	ldata->echo_head = ldata->echo_tail = ldata->echo_commit = 0;
+	ldata->line_start = 0;
 
-	raw_spin_lock_irqsave(&ldata->read_lock, flags);
-	ldata->read_head = ldata->read_tail = ldata->read_cnt = 0;
-	raw_spin_unlock_irqrestore(&ldata->read_lock, flags);
-
-	mutex_lock(&ldata->echo_lock);
-	ldata->echo_pos = ldata->echo_cnt = ldata->echo_overrun = 0;
-	mutex_unlock(&ldata->echo_lock);
-
-	ldata->canon_head = ldata->canon_data = ldata->erasing = 0;
+	ldata->erasing = 0;
 	bitmap_zero(ldata->read_flags, N_TTY_BUF_SIZE);
 }
 
@@ -251,16 +362,21 @@ static void n_tty_packet_mode_flush(struct tty_struct *tty)
  *	buffer flushed (eg at hangup) or when the N_TTY line discipline
  *	internally has to clean the pending queue (for example some signals).
  *
- *	Locking: ctrl_lock, read_lock.
+ *	Holds termios_rwsem to exclude producer/consumer while
+ *	buffer indices are reset.
+ *
+ *	Locking: ctrl_lock, exclusive termios_rwsem
  */
 
 static void n_tty_flush_buffer(struct tty_struct *tty)
 {
+	down_write(&tty->termios_rwsem);
 	reset_buffer_flags(tty->disc_data);
 	n_tty_set_room(tty);
 
 	if (tty->link)
 		n_tty_packet_mode_flush(tty);
+	up_write(&tty->termios_rwsem);
 }
 
 /**
@@ -270,24 +386,18 @@ static void n_tty_flush_buffer(struct tty_struct *tty)
  *	Report the number of characters buffered to be delivered to user
  *	at this instant in time.
  *
- *	Locking: read_lock
+ *	Locking: exclusive termios_rwsem
  */
 
 static ssize_t n_tty_chars_in_buffer(struct tty_struct *tty)
 {
-	struct n_tty_data *ldata = tty->disc_data;
-	unsigned long flags;
-	ssize_t n = 0;
+	ssize_t n;
 
-	raw_spin_lock_irqsave(&ldata->read_lock, flags);
-	if (!ldata->icanon) {
-		n = ldata->read_cnt;
-	} else if (ldata->canon_data) {
-		n = (ldata->canon_head > ldata->read_tail) ?
-			ldata->canon_head - ldata->read_tail :
-			ldata->canon_head + (N_TTY_BUF_SIZE - ldata->read_tail);
-	}
-	raw_spin_unlock_irqrestore(&ldata->read_lock, flags);
+	WARN_ONCE(1, "%s is deprecated and scheduled for removal.", __func__);
+
+	down_write(&tty->termios_rwsem);
+	n = chars_in_buffer(tty);
+	up_write(&tty->termios_rwsem);
 	return n;
 }
 
@@ -532,33 +642,23 @@ break_out:
  *	are prioritized.  Also, when control characters are echoed with a
  *	prefixed "^", the pair is treated atomically and thus not separated.
  *
- *	Locking: output_lock to protect column state and space left,
- *		 echo_lock to protect the echo buffer
+ *	Locking: callers must hold output_lock
  */
 
-static void process_echoes(struct tty_struct *tty)
+static size_t __process_echoes(struct tty_struct *tty)
 {
 	struct n_tty_data *ldata = tty->disc_data;
-	int	space, nr;
+	int	space, old_space;
+	size_t tail;
 	unsigned char c;
-	unsigned char *cp, *buf_end;
-
-	if (!ldata->echo_cnt)
-		return;
-
-	mutex_lock(&ldata->output_lock);
-	mutex_lock(&ldata->echo_lock);
 
-	space = tty_write_room(tty);
+	old_space = space = tty_write_room(tty);
 
-	buf_end = ldata->echo_buf + N_TTY_BUF_SIZE;
-	cp = ldata->echo_buf + ldata->echo_pos;
-	nr = ldata->echo_cnt;
-	while (nr > 0) {
-		c = *cp;
+	tail = ldata->echo_tail;
+	while (ldata->echo_commit != tail) {
+		c = echo_buf(ldata, tail);
 		if (c == ECHO_OP_START) {
 			unsigned char op;
-			unsigned char *opp;
 			int no_space_left = 0;
 
 			/*
@@ -566,18 +666,13 @@ static void process_echoes(struct tty_struct *tty)
 			 * operation, get the next byte, which is either the
 			 * op code or a control character value.
 			 */
-			opp = cp + 1;
-			if (opp == buf_end)
-				opp -= N_TTY_BUF_SIZE;
-			op = *opp;
+			op = echo_buf(ldata, tail + 1);
 
 			switch (op) {
 				unsigned int num_chars, num_bs;
 
 			case ECHO_OP_ERASE_TAB:
-				if (++opp == buf_end)
-					opp -= N_TTY_BUF_SIZE;
-				num_chars = *opp;
+				num_chars = echo_buf(ldata, tail + 2);
 
 				/*
 				 * Determine how many columns to go back
@@ -603,21 +698,18 @@ static void process_echoes(struct tty_struct *tty)
 					if (ldata->column > 0)
 						ldata->column--;
 				}
-				cp += 3;
-				nr -= 3;
+				tail += 3;
 				break;
 
 			case ECHO_OP_SET_CANON_COL:
 				ldata->canon_column = ldata->column;
-				cp += 2;
-				nr -= 2;
+				tail += 2;
 				break;
 
 			case ECHO_OP_MOVE_BACK_COL:
 				if (ldata->column > 0)
 					ldata->column--;
-				cp += 2;
-				nr -= 2;
+				tail += 2;
 				break;
 
 			case ECHO_OP_START:
@@ -629,8 +721,7 @@ static void process_echoes(struct tty_struct *tty)
 				tty_put_char(tty, ECHO_OP_START);
 				ldata->column++;
 				space--;
-				cp += 2;
-				nr -= 2;
+				tail += 2;
 				break;
 
 			default:
@@ -651,8 +742,7 @@ static void process_echoes(struct tty_struct *tty)
 				tty_put_char(tty, op ^ 0100);
 				ldata->column += 2;
 				space -= 2;
-				cp += 2;
-				nr -= 2;
+				tail += 2;
 			}
 
 			if (no_space_left)
@@ -669,80 +759,92 @@ static void process_echoes(struct tty_struct *tty)
 				tty_put_char(tty, c);
 				space -= 1;
 			}
-			cp += 1;
-			nr -= 1;
+			tail += 1;
 		}
-
-		/* When end of circular buffer reached, wrap around */
-		if (cp >= buf_end)
-			cp -= N_TTY_BUF_SIZE;
 	}
 
-	if (nr == 0) {
-		ldata->echo_pos = 0;
-		ldata->echo_cnt = 0;
-		ldata->echo_overrun = 0;
-	} else {
-		int num_processed = ldata->echo_cnt - nr;
-		ldata->echo_pos += num_processed;
-		ldata->echo_pos &= N_TTY_BUF_SIZE - 1;
-		ldata->echo_cnt = nr;
-		if (num_processed > 0)
-			ldata->echo_overrun = 0;
+	/* If the echo buffer is nearly full (so that the possibility exists
+	 * of echo overrun before the next commit), then discard enough
+	 * data at the tail to prevent a subsequent overrun */
+	while (ldata->echo_commit - tail >= ECHO_DISCARD_WATERMARK) {
+		if (echo_buf(ldata, tail == ECHO_OP_START)) {
+			if (echo_buf(ldata, tail) == ECHO_OP_ERASE_TAB)
+				tail += 3;
+			else
+				tail += 2;
+		} else
+			tail++;
 	}
 
-	mutex_unlock(&ldata->echo_lock);
+	ldata->echo_tail = tail;
+	return old_space - space;
+}
+
+static void commit_echoes(struct tty_struct *tty)
+{
+	struct n_tty_data *ldata = tty->disc_data;
+	size_t nr, old, echoed;
+	size_t head;
+
+	head = ldata->echo_head;
+	old = ldata->echo_commit - ldata->echo_tail;
+
+	/* Process committed echoes if the accumulated # of bytes
+	 * is over the threshold (and try again each time another
+	 * block is accumulated) */
+	nr = head - ldata->echo_tail;
+	if (nr < ECHO_COMMIT_WATERMARK || (nr % ECHO_BLOCK > old % ECHO_BLOCK))
+		return;
+
+	mutex_lock(&ldata->output_lock);
+	ldata->echo_commit = head;
+	echoed = __process_echoes(tty);
+	mutex_unlock(&ldata->output_lock);
+
+	if (echoed && tty->ops->flush_chars)
+		tty->ops->flush_chars(tty);
+}
+
+static void process_echoes(struct tty_struct *tty)
+{
+	struct n_tty_data *ldata = tty->disc_data;
+	size_t echoed;
+
+	if (!L_ECHO(tty) || ldata->echo_commit == ldata->echo_tail)
+		return;
+
+	mutex_lock(&ldata->output_lock);
+	echoed = __process_echoes(tty);
 	mutex_unlock(&ldata->output_lock);
 
-	if (tty->ops->flush_chars)
+	if (echoed && tty->ops->flush_chars)
 		tty->ops->flush_chars(tty);
 }
 
+static void flush_echoes(struct tty_struct *tty)
+{
+	struct n_tty_data *ldata = tty->disc_data;
+
+	if (!L_ECHO(tty) || ldata->echo_commit == ldata->echo_head)
+		return;
+
+	mutex_lock(&ldata->output_lock);
+	ldata->echo_commit = ldata->echo_head;
+	__process_echoes(tty);
+	mutex_unlock(&ldata->output_lock);
+}
+
 /**
  *	add_echo_byte	-	add a byte to the echo buffer
  *	@c: unicode byte to echo
  *	@ldata: n_tty data
  *
  *	Add a character or operation byte to the echo buffer.
- *
- *	Should be called under the echo lock to protect the echo buffer.
  */
 
-static void add_echo_byte(unsigned char c, struct n_tty_data *ldata)
+static inline void add_echo_byte(unsigned char c, struct n_tty_data *ldata)
 {
-	int	new_byte_pos;
-
-	if (ldata->echo_cnt == N_TTY_BUF_SIZE) {
-		/* Circular buffer is already at capacity */
-		new_byte_pos = ldata->echo_pos;
-
-		/*
-		 * Since the buffer start position needs to be advanced,
-		 * be sure to step by a whole operation byte group.
-		 */
-		if (ldata->echo_buf[ldata->echo_pos] == ECHO_OP_START) {
-			if (ldata->echo_buf[(ldata->echo_pos + 1) &
-					  (N_TTY_BUF_SIZE - 1)] ==
-						ECHO_OP_ERASE_TAB) {
-				ldata->echo_pos += 3;
-				ldata->echo_cnt -= 2;
-			} else {
-				ldata->echo_pos += 2;
-				ldata->echo_cnt -= 1;
-			}
-		} else {
-			ldata->echo_pos++;
-		}
-		ldata->echo_pos &= N_TTY_BUF_SIZE - 1;
-
-		ldata->echo_overrun = 1;
-	} else {
-		new_byte_pos = ldata->echo_pos + ldata->echo_cnt;
-		new_byte_pos &= N_TTY_BUF_SIZE - 1;
-		ldata->echo_cnt++;
-	}
-
-	ldata->echo_buf[new_byte_pos] = c;
+	*echo_buf_addr(ldata, ldata->echo_head++) = c;
 }
 
 /**
@@ -750,16 +852,12 @@ static void add_echo_byte(unsigned char c, struct n_tty_data *ldata)
  *	@ldata: n_tty data
  *
  *	Add an operation to the echo buffer to move back one column.
- *
- *	Locking: echo_lock to protect the echo buffer
  */
 
 static void echo_move_back_col(struct n_tty_data *ldata)
 {
-	mutex_lock(&ldata->echo_lock);
 	add_echo_byte(ECHO_OP_START, ldata);
 	add_echo_byte(ECHO_OP_MOVE_BACK_COL, ldata);
-	mutex_unlock(&ldata->echo_lock);
 }
 
 /**
@@ -768,16 +866,12 @@ static void echo_move_back_col(struct n_tty_data *ldata)
  *
  *	Add an operation to the echo buffer to set the canon column
  *	to the current column.
- *
- *	Locking: echo_lock to protect the echo buffer
  */
 
 static void echo_set_canon_col(struct n_tty_data *ldata)
 {
-	mutex_lock(&ldata->echo_lock);
 	add_echo_byte(ECHO_OP_START, ldata);
 	add_echo_byte(ECHO_OP_SET_CANON_COL, ldata);
-	mutex_unlock(&ldata->echo_lock);
 }
 
 /**
@@ -793,15 +887,11 @@ static void echo_set_canon_col(struct n_tty_data *ldata)
  *	of input.  This information will be used later, along with
  *	canon column (if applicable), to go back the correct number
  *	of columns.
- *
- *	Locking: echo_lock to protect the echo buffer
  */
 
 static void echo_erase_tab(unsigned int num_chars, int after_tab,
 			   struct n_tty_data *ldata)
 {
-	mutex_lock(&ldata->echo_lock);
-
 	add_echo_byte(ECHO_OP_START, ldata);
 	add_echo_byte(ECHO_OP_ERASE_TAB, ldata);
 
@@ -813,8 +903,6 @@ static void echo_erase_tab(unsigned int num_chars, int after_tab,
 		num_chars |= 0x80;
 
 	add_echo_byte(num_chars, ldata);
-
-	mutex_unlock(&ldata->echo_lock);
 }
 
 /**
@@ -826,20 +914,16 @@ static void echo_erase_tab(unsigned int num_chars, int after_tab,
  *	L_ECHO(tty) is true. Called from the driver receive_buf path.
  *
  *	This variant does not treat control characters specially.
- *
- *	Locking: echo_lock to protect the echo buffer
  */
 
 static void echo_char_raw(unsigned char c, struct n_tty_data *ldata)
 {
-	mutex_lock(&ldata->echo_lock);
 	if (c == ECHO_OP_START) {
 		add_echo_byte(ECHO_OP_START, ldata);
 		add_echo_byte(ECHO_OP_START, ldata);
 	} else {
 		add_echo_byte(c, ldata);
 	}
-	mutex_unlock(&ldata->echo_lock);
 }
 
 /**
@@ -852,16 +936,12 @@ static void echo_char_raw(unsigned char c, struct n_tty_data *ldata)
  *
  *	This variant tags control characters to be echoed as "^X"
  *	(where X is the letter representing the control char).
- *
- *	Locking: echo_lock to protect the echo buffer
  */
 
 static void echo_char(unsigned char c, struct tty_struct *tty)
 {
 	struct n_tty_data *ldata = tty->disc_data;
 
-	mutex_lock(&ldata->echo_lock);
-
 	if (c == ECHO_OP_START) {
 		add_echo_byte(ECHO_OP_START, ldata);
 		add_echo_byte(ECHO_OP_START, ldata);
@@ -870,8 +950,6 @@ static void echo_char(unsigned char c, struct tty_struct *tty)
 			add_echo_byte(ECHO_OP_START, ldata);
 		add_echo_byte(c, ldata);
 	}
-
-	mutex_unlock(&ldata->echo_lock);
 }
 
 /**
@@ -896,17 +974,22 @@ static inline void finish_erasing(struct n_tty_data *ldata)
  *	present in the stream from the driver layer. Handles the complexities
  *	of UTF-8 multibyte symbols.
  *
- *	Locking: read_lock for tty buffers
+ *	n_tty_receive_buf()/producer path:
+ *		caller holds non-exclusive termios_rwsem
+ *		modifies read_head
+ *
+ *	Modifying the read_head is not considered a publish in this context
+ *	because canonical mode is active -- only canon_head publishes
  */
 
 static void eraser(unsigned char c, struct tty_struct *tty)
 {
 	struct n_tty_data *ldata = tty->disc_data;
 	enum { ERASE, WERASE, KILL } kill_type;
-	int head, seen_alnums, cnt;
-	unsigned long flags;
+	size_t head;
+	size_t cnt;
+	int seen_alnums;
 
-	/* FIXME: locking needed ? */
 	if (ldata->read_head == ldata->canon_head) {
 		/* process_output('\a', tty); */ /* what do you think? */
 		return;
@@ -917,19 +1000,11 @@ static void eraser(unsigned char c, struct tty_struct *tty)
 		kill_type = WERASE;
 	else {
 		if (!L_ECHO(tty)) {
-			raw_spin_lock_irqsave(&ldata->read_lock, flags);
-			ldata->read_cnt -= ((ldata->read_head - ldata->canon_head) &
-					  (N_TTY_BUF_SIZE - 1));
 			ldata->read_head = ldata->canon_head;
-			raw_spin_unlock_irqrestore(&ldata->read_lock, flags);
 			return;
 		}
 		if (!L_ECHOK(tty) || !L_ECHOKE(tty) || !L_ECHOE(tty)) {
-			raw_spin_lock_irqsave(&ldata->read_lock, flags);
-			ldata->read_cnt -= ((ldata->read_head - ldata->canon_head) &
-					  (N_TTY_BUF_SIZE - 1));
 			ldata->read_head = ldata->canon_head;
-			raw_spin_unlock_irqrestore(&ldata->read_lock, flags);
 			finish_erasing(ldata);
 			echo_char(KILL_CHAR(tty), tty);
 			/* Add a newline if ECHOK is on and ECHOKE is off. */
@@ -941,14 +1016,13 @@ static void eraser(unsigned char c, struct tty_struct *tty)
 	}
 
 	seen_alnums = 0;
-	/* FIXME: Locking ?? */
 	while (ldata->read_head != ldata->canon_head) {
 		head = ldata->read_head;
 
 		/* erase a single possibly multibyte character */
 		do {
-			head = (head - 1) & (N_TTY_BUF_SIZE-1);
-			c = ldata->read_buf[head];
+			head--;
+			c = read_buf(ldata, head);
 		} while (is_continuation(c, tty) && head != ldata->canon_head);
 
 		/* do not partially erase */
@@ -962,11 +1036,8 @@ static void eraser(unsigned char c, struct tty_struct *tty)
 			else if (seen_alnums)
 				break;
 		}
-		cnt = (ldata->read_head - head) & (N_TTY_BUF_SIZE-1);
-		raw_spin_lock_irqsave(&ldata->read_lock, flags);
+		cnt = ldata->read_head - head;
 		ldata->read_head = head;
-		ldata->read_cnt -= cnt;
-		raw_spin_unlock_irqrestore(&ldata->read_lock, flags);
 		if (L_ECHO(tty)) {
 			if (L_ECHOPRT(tty)) {
 				if (!ldata->erasing) {
@@ -976,9 +1047,8 @@ static void eraser(unsigned char c, struct tty_struct *tty)
 				/* if cnt > 1, output a multi-byte character */
 				echo_char(c, tty);
 				while (--cnt > 0) {
-					head = (head+1) & (N_TTY_BUF_SIZE-1);
-					echo_char_raw(ldata->read_buf[head],
-							ldata);
+					head++;
+					echo_char_raw(read_buf(ldata, head), ldata);
 					echo_move_back_col(ldata);
 				}
 			} else if (kill_type == ERASE && !L_ECHOE(tty)) {
@@ -986,7 +1056,7 @@ static void eraser(unsigned char c, struct tty_struct *tty)
 			} else if (c == '\t') {
 				unsigned int num_chars = 0;
 				int after_tab = 0;
-				unsigned long tail = ldata->read_head;
+				size_t tail = ldata->read_head;
 
 				/*
 				 * Count the columns used for characters
@@ -996,8 +1066,8 @@ static void eraser(unsigned char c, struct tty_struct *tty)
 				 * number of columns.
 				 */
 				while (tail != ldata->canon_head) {
-					tail = (tail-1) & (N_TTY_BUF_SIZE-1);
-					c = ldata->read_buf[tail];
+					tail--;
+					c = read_buf(ldata, tail);
 					if (c == '\t') {
 						after_tab = 1;
 						break;
@@ -1040,7 +1110,7 @@ static void eraser(unsigned char c, struct tty_struct *tty)
  *	Locking: ctrl_lock
  */
 
-static inline void isig(int sig, struct tty_struct *tty)
+static void isig(int sig, struct tty_struct *tty)
 {
 	struct pid *tty_pgrp = tty_get_pgrp(tty);
 	if (tty_pgrp) {
@@ -1056,10 +1126,14 @@ static inline void isig(int sig, struct tty_struct *tty)
  *	An RS232 break event has been hit in the incoming bitstream. This
  *	can cause a variety of events depending upon the termios settings.
  *
- *	Called from the receive_buf path so single threaded.
+ *	n_tty_receive_buf()/producer path:
+ *		caller holds non-exclusive termios_rwsem
+ *		publishes read_head via put_tty_queue()
+ *
+ *	Note: may get exclusive termios_rwsem if flushing input buffer
  */
 
-static inline void n_tty_receive_break(struct tty_struct *tty)
+static void n_tty_receive_break(struct tty_struct *tty)
 {
 	struct n_tty_data *ldata = tty->disc_data;
 
@@ -1068,8 +1142,11 @@ static inline void n_tty_receive_break(struct tty_struct *tty)
 	if (I_BRKINT(tty)) {
 		isig(SIGINT, tty);
 		if (!L_NOFLSH(tty)) {
+			/* flushing needs exclusive termios_rwsem */
+			up_read(&tty->termios_rwsem);
 			n_tty_flush_buffer(tty);
 			tty_driver_flush_buffer(tty);
+			down_read(&tty->termios_rwsem);
 		}
 		return;
 	}
@@ -1094,7 +1171,7 @@ static inline void n_tty_receive_break(struct tty_struct *tty)
  *	private.
  */
 
-static inline void n_tty_receive_overrun(struct tty_struct *tty)
+static void n_tty_receive_overrun(struct tty_struct *tty)
 {
 	struct n_tty_data *ldata = tty->disc_data;
 	char buf[64];
@@ -1116,10 +1193,13 @@ static inline void n_tty_receive_overrun(struct tty_struct *tty)
  *	@c: character
  *
  *	Process a parity error and queue the right data to indicate
- *	the error case if necessary. Locking as per n_tty_receive_buf.
+ *	the error case if necessary.
+ *
+ *	n_tty_receive_buf()/producer path:
+ *		caller holds non-exclusive termios_rwsem
+ *		publishes read_head via put_tty_queue()
  */
-static inline void n_tty_receive_parity_error(struct tty_struct *tty,
-					      unsigned char c)
+static void n_tty_receive_parity_error(struct tty_struct *tty, unsigned char c)
 {
 	struct n_tty_data *ldata = tty->disc_data;
 
@@ -1136,6 +1216,26 @@ static inline void n_tty_receive_parity_error(struct tty_struct *tty,
 	wake_up_interruptible(&tty->read_wait);
 }
 
+static void
+n_tty_receive_signal_char(struct tty_struct *tty, int signal, unsigned char c)
+{
+	if (!L_NOFLSH(tty)) {
+		/* flushing needs exclusive termios_rwsem */
+		up_read(&tty->termios_rwsem);
+		n_tty_flush_buffer(tty);
+		tty_driver_flush_buffer(tty);
+		down_read(&tty->termios_rwsem);
+	}
+	if (I_IXON(tty))
+		start_tty(tty);
+	if (L_ECHO(tty)) {
+		echo_char(c, tty);
+		commit_echoes(tty);
+	}
+	isig(signal, tty);
+	return;
+}
+
 /**
  *	n_tty_receive_char	-	perform processing
  *	@tty: terminal device
@@ -1144,117 +1244,54 @@ static inline void n_tty_receive_parity_error(struct tty_struct *tty,
  *	Process an individual character of input received from the driver.
  *	This is serialized with respect to itself by the rules for the
  *	driver above.
+ *
+ *	n_tty_receive_buf()/producer path:
+ *		caller holds non-exclusive termios_rwsem
+ *		publishes canon_head if canonical mode is active
+ *		otherwise, publishes read_head via put_tty_queue()
+ *
+ *	Returns 1 if LNEXT was received, else returns 0
  */
 
-static inline void n_tty_receive_char(struct tty_struct *tty, unsigned char c)
+static int
+n_tty_receive_char_special(struct tty_struct *tty, unsigned char c)
 {
 	struct n_tty_data *ldata = tty->disc_data;
-	unsigned long flags;
 	int parmrk;
 
-	if (ldata->raw) {
-		put_tty_queue(c, ldata);
-		return;
-	}
-
-	if (I_ISTRIP(tty))
-		c &= 0x7f;
-	if (I_IUCLC(tty) && L_IEXTEN(tty))
-		c = tolower(c);
-
-	if (L_EXTPROC(tty)) {
-		put_tty_queue(c, ldata);
-		return;
-	}
-
-	if (tty->stopped && !tty->flow_stopped && I_IXON(tty) &&
-	    I_IXANY(tty) && c != START_CHAR(tty) && c != STOP_CHAR(tty) &&
-	    c != INTR_CHAR(tty) && c != QUIT_CHAR(tty) && c != SUSP_CHAR(tty)) {
-		start_tty(tty);
-		process_echoes(tty);
-	}
-
-	if (tty->closing) {
-		if (I_IXON(tty)) {
-			if (c == START_CHAR(tty)) {
-				start_tty(tty);
-				process_echoes(tty);
-			} else if (c == STOP_CHAR(tty))
-				stop_tty(tty);
-		}
-		return;
-	}
-
-	/*
-	 * If the previous character was LNEXT, or we know that this
-	 * character is not one of the characters that we'll have to
-	 * handle specially, do shortcut processing to speed things
-	 * up.
-	 */
-	if (!test_bit(c, ldata->process_char_map) || ldata->lnext) {
-		ldata->lnext = 0;
-		parmrk = (c == (unsigned char) '\377' && I_PARMRK(tty)) ? 1 : 0;
-		if (ldata->read_cnt >= (N_TTY_BUF_SIZE - parmrk - 1)) {
-			/* beep if no space */
-			if (L_ECHO(tty))
-				process_output('\a', tty);
-			return;
-		}
-		if (L_ECHO(tty)) {
-			finish_erasing(ldata);
-			/* Record the column of first canon char. */
-			if (ldata->canon_head == ldata->read_head)
-				echo_set_canon_col(ldata);
-			echo_char(c, tty);
-			process_echoes(tty);
-		}
-		if (parmrk)
-			put_tty_queue(c, ldata);
-		put_tty_queue(c, ldata);
-		return;
-	}
-
 	if (I_IXON(tty)) {
 		if (c == START_CHAR(tty)) {
 			start_tty(tty);
-			process_echoes(tty);
-			return;
+			commit_echoes(tty);
+			return 0;
 		}
 		if (c == STOP_CHAR(tty)) {
 			stop_tty(tty);
-			return;
+			return 0;
 		}
 	}
 
 	if (L_ISIG(tty)) {
-		int signal;
-		signal = SIGINT;
-		if (c == INTR_CHAR(tty))
-			goto send_signal;
-		signal = SIGQUIT;
-		if (c == QUIT_CHAR(tty))
-			goto send_signal;
-		signal = SIGTSTP;
-		if (c == SUSP_CHAR(tty)) {
-send_signal:
-			if (!L_NOFLSH(tty)) {
-				n_tty_flush_buffer(tty);
-				tty_driver_flush_buffer(tty);
-			}
-			if (I_IXON(tty))
-				start_tty(tty);
-			if (L_ECHO(tty)) {
-				echo_char(c, tty);
-				process_echoes(tty);
-			}
-			isig(signal, tty);
-			return;
+		if (c == INTR_CHAR(tty)) {
+			n_tty_receive_signal_char(tty, SIGINT, c);
+			return 0;
+		} else if (c == QUIT_CHAR(tty)) {
+			n_tty_receive_signal_char(tty, SIGQUIT, c);
+			return 0;
+		} else if (c == SUSP_CHAR(tty)) {
+			n_tty_receive_signal_char(tty, SIGTSTP, c);
+			return 0;
 		}
 	}
 
+	if (tty->stopped && !tty->flow_stopped && I_IXON(tty) && I_IXANY(tty)) {
+		start_tty(tty);
+		process_echoes(tty);
+	}
+
 	if (c == '\r') {
 		if (I_IGNCR(tty))
-			return;
+			return 0;
 		if (I_ICRNL(tty))
 			c = '\n';
 	} else if (c == '\n' && I_INLCR(tty))
@@ -1264,8 +1301,8 @@ send_signal:
 		if (c == ERASE_CHAR(tty) || c == KILL_CHAR(tty) ||
 		    (c == WERASE_CHAR(tty) && L_IEXTEN(tty))) {
 			eraser(c, tty);
-			process_echoes(tty);
-			return;
+			commit_echoes(tty);
+			return 0;
 		}
 		if (c == LNEXT_CHAR(tty) && L_IEXTEN(tty)) {
 			ldata->lnext = 1;
@@ -1274,42 +1311,32 @@ send_signal:
 				if (L_ECHOCTL(tty)) {
 					echo_char_raw('^', ldata);
 					echo_char_raw('\b', ldata);
-					process_echoes(tty);
+					commit_echoes(tty);
 				}
 			}
-			return;
+			return 1;
 		}
-		if (c == REPRINT_CHAR(tty) && L_ECHO(tty) &&
-		    L_IEXTEN(tty)) {
-			unsigned long tail = ldata->canon_head;
+		if (c == REPRINT_CHAR(tty) && L_ECHO(tty) && L_IEXTEN(tty)) {
+			size_t tail = ldata->canon_head;
 
 			finish_erasing(ldata);
 			echo_char(c, tty);
 			echo_char_raw('\n', ldata);
 			while (tail != ldata->read_head) {
-				echo_char(ldata->read_buf[tail], tty);
-				tail = (tail+1) & (N_TTY_BUF_SIZE-1);
+				echo_char(read_buf(ldata, tail), tty);
+				tail++;
 			}
-			process_echoes(tty);
-			return;
+			commit_echoes(tty);
+			return 0;
 		}
 		if (c == '\n') {
-			if (ldata->read_cnt >= N_TTY_BUF_SIZE) {
-				if (L_ECHO(tty))
-					process_output('\a', tty);
-				return;
-			}
 			if (L_ECHO(tty) || L_ECHONL(tty)) {
 				echo_char_raw('\n', ldata);
-				process_echoes(tty);
+				commit_echoes(tty);
 			}
 			goto handle_newline;
 		}
 		if (c == EOF_CHAR(tty)) {
-			if (ldata->read_cnt >= N_TTY_BUF_SIZE)
-				return;
-			if (ldata->canon_head != ldata->read_head)
-				set_bit(TTY_PUSH, &tty->flags);
 			c = __DISABLED_CHAR;
 			goto handle_newline;
 		}
@@ -1317,11 +1344,6 @@ send_signal:
 		    (c == EOL2_CHAR(tty) && L_IEXTEN(tty))) {
 			parmrk = (c == (unsigned char) '\377' && I_PARMRK(tty))
 				 ? 1 : 0;
-			if (ldata->read_cnt >= (N_TTY_BUF_SIZE - parmrk)) {
-				if (L_ECHO(tty))
-					process_output('\a', tty);
-				return;
-			}
 			/*
 			 * XXX are EOL_CHAR and EOL2_CHAR echoed?!?
 			 */
@@ -1330,7 +1352,7 @@ send_signal:
 				if (ldata->canon_head == ldata->read_head)
 					echo_set_canon_col(ldata);
 				echo_char(c, tty);
-				process_echoes(tty);
+				commit_echoes(tty);
 			}
 			/*
 			 * XXX does PARMRK doubling happen for
@@ -1340,26 +1362,17 @@ send_signal:
 				put_tty_queue(c, ldata);
 
 handle_newline:
-			raw_spin_lock_irqsave(&ldata->read_lock, flags);
-			set_bit(ldata->read_head, ldata->read_flags);
-			put_tty_queue_nolock(c, ldata);
+			set_bit(ldata->read_head & (N_TTY_BUF_SIZE - 1), ldata->read_flags);
+			put_tty_queue(c, ldata);
 			ldata->canon_head = ldata->read_head;
-			ldata->canon_data++;
-			raw_spin_unlock_irqrestore(&ldata->read_lock, flags);
 			kill_fasync(&tty->fasync, SIGIO, POLL_IN);
 			if (waitqueue_active(&tty->read_wait))
 				wake_up_interruptible(&tty->read_wait);
-			return;
+			return 0;
 		}
 	}
 
 	parmrk = (c == (unsigned char) '\377' && I_PARMRK(tty)) ? 1 : 0;
-	if (ldata->read_cnt >= (N_TTY_BUF_SIZE - parmrk - 1)) {
-		/* beep if no space */
-		if (L_ECHO(tty))
-			process_output('\a', tty);
-		return;
-	}
 	if (L_ECHO(tty)) {
 		finish_erasing(ldata);
 		if (c == '\n')
@@ -1370,29 +1383,123 @@ handle_newline:
 				echo_set_canon_col(ldata);
 			echo_char(c, tty);
 		}
-		process_echoes(tty);
+		commit_echoes(tty);
 	}
 
 	if (parmrk)
 		put_tty_queue(c, ldata);
 
 	put_tty_queue(c, ldata);
+	return 0;
 }
 
+static inline void
+n_tty_receive_char_inline(struct tty_struct *tty, unsigned char c)
+{
+	struct n_tty_data *ldata = tty->disc_data;
+	int parmrk;
 
-/**
- *	n_tty_write_wakeup	-	asynchronous I/O notifier
- *	@tty: tty device
- *
- *	Required for the ptys, serial driver etc. since processes
- *	that attach themselves to the master and rely on ASYNC
- *	IO must be woken up
- */
+	if (tty->stopped && !tty->flow_stopped && I_IXON(tty) && I_IXANY(tty)) {
+		start_tty(tty);
+		process_echoes(tty);
+	}
+	if (L_ECHO(tty)) {
+		finish_erasing(ldata);
+		/* Record the column of first canon char. */
+		if (ldata->canon_head == ldata->read_head)
+			echo_set_canon_col(ldata);
+		echo_char(c, tty);
+		commit_echoes(tty);
+	}
+	parmrk = (c == (unsigned char) '\377' && I_PARMRK(tty)) ? 1 : 0;
+	if (parmrk)
+		put_tty_queue(c, ldata);
+	put_tty_queue(c, ldata);
+}
 
-static void n_tty_write_wakeup(struct tty_struct *tty)
+static inline void n_tty_receive_char(struct tty_struct *tty, unsigned char c)
 {
-	if (tty->fasync && test_and_clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags))
-		kill_fasync(&tty->fasync, SIGIO, POLL_OUT);
+	n_tty_receive_char_inline(tty, c);
+}
+
+static inline void
+n_tty_receive_char_fast(struct tty_struct *tty, unsigned char c)
+{
+	struct n_tty_data *ldata = tty->disc_data;
+
+	if (tty->stopped && !tty->flow_stopped && I_IXON(tty) && I_IXANY(tty)) {
+		start_tty(tty);
+		process_echoes(tty);
+	}
+	if (L_ECHO(tty)) {
+		finish_erasing(ldata);
+		/* Record the column of first canon char. */
+		if (ldata->canon_head == ldata->read_head)
+			echo_set_canon_col(ldata);
+		echo_char(c, tty);
+		commit_echoes(tty);
+	}
+	put_tty_queue(c, ldata);
+}
+
+static inline void
+n_tty_receive_char_closing(struct tty_struct *tty, unsigned char c)
+{
+	if (I_ISTRIP(tty))
+		c &= 0x7f;
+	if (I_IUCLC(tty) && L_IEXTEN(tty))
+		c = tolower(c);
+
+	if (I_IXON(tty)) {
+		if (c == STOP_CHAR(tty))
+			stop_tty(tty);
+		else if (c == START_CHAR(tty) ||
+			 (tty->stopped && !tty->flow_stopped && I_IXANY(tty) &&
+			  c != INTR_CHAR(tty) && c != QUIT_CHAR(tty) &&
+			  c != SUSP_CHAR(tty))) {
+			start_tty(tty);
+			process_echoes(tty);
+		}
+	}
+}
+
+static void
+n_tty_receive_char_flagged(struct tty_struct *tty, unsigned char c, char flag)
+{
+	char buf[64];
+
+	switch (flag) {
+	case TTY_BREAK:
+		n_tty_receive_break(tty);
+		break;
+	case TTY_PARITY:
+	case TTY_FRAME:
+		n_tty_receive_parity_error(tty, c);
+		break;
+	case TTY_OVERRUN:
+		n_tty_receive_overrun(tty);
+		break;
+	default:
+		printk(KERN_ERR "%s: unknown flag %d\n",
+		       tty_name(tty, buf), flag);
+		break;
+	}
+}
+
+static void
+n_tty_receive_char_lnext(struct tty_struct *tty, unsigned char c, char flag)
+{
+	struct n_tty_data *ldata = tty->disc_data;
+
+	ldata->lnext = 0;
+	if (likely(flag == TTY_NORMAL)) {
+		if (I_ISTRIP(tty))
+			c &= 0x7f;
+		if (I_IUCLC(tty) && L_IEXTEN(tty))
+			c = tolower(c);
+		n_tty_receive_char(tty, c);
+	} else
+		n_tty_receive_char_flagged(tty, c, flag);
 }
 
 /**
@@ -1406,86 +1513,220 @@ static void n_tty_write_wakeup(struct tty_struct *tty)
  *	been received. This function must be called from soft contexts
  *	not from interrupt context. The driver is responsible for making
  *	calls one at a time and in order (or using flush_to_ldisc)
+ *
+ *	n_tty_receive_buf()/producer path:
+ *		claims non-exclusive termios_rwsem
+ *		publishes read_head and canon_head
  */
 
-static void n_tty_receive_buf(struct tty_struct *tty, const unsigned char *cp,
-			      char *fp, int count)
+static void
+n_tty_receive_buf_real_raw(struct tty_struct *tty, const unsigned char *cp,
+			   char *fp, int count)
 {
 	struct n_tty_data *ldata = tty->disc_data;
-	const unsigned char *p;
-	char *f, flags = TTY_NORMAL;
-	int	i;
-	char	buf[64];
-	unsigned long cpuflags;
-
-	if (ldata->real_raw) {
-		raw_spin_lock_irqsave(&ldata->read_lock, cpuflags);
-		i = min(N_TTY_BUF_SIZE - ldata->read_cnt,
-			N_TTY_BUF_SIZE - ldata->read_head);
-		i = min(count, i);
-		memcpy(ldata->read_buf + ldata->read_head, cp, i);
-		ldata->read_head = (ldata->read_head + i) & (N_TTY_BUF_SIZE-1);
-		ldata->read_cnt += i;
-		cp += i;
-		count -= i;
-
-		i = min(N_TTY_BUF_SIZE - ldata->read_cnt,
-			N_TTY_BUF_SIZE - ldata->read_head);
-		i = min(count, i);
-		memcpy(ldata->read_buf + ldata->read_head, cp, i);
-		ldata->read_head = (ldata->read_head + i) & (N_TTY_BUF_SIZE-1);
-		ldata->read_cnt += i;
-		raw_spin_unlock_irqrestore(&ldata->read_lock, cpuflags);
-	} else {
-		for (i = count, p = cp, f = fp; i; i--, p++) {
-			if (f)
-				flags = *f++;
-			switch (flags) {
-			case TTY_NORMAL:
-				n_tty_receive_char(tty, *p);
-				break;
-			case TTY_BREAK:
-				n_tty_receive_break(tty);
-				break;
-			case TTY_PARITY:
-			case TTY_FRAME:
-				n_tty_receive_parity_error(tty, *p);
-				break;
-			case TTY_OVERRUN:
-				n_tty_receive_overrun(tty);
-				break;
-			default:
-				printk(KERN_ERR "%s: unknown flag %d\n",
-				       tty_name(tty, buf), flags);
-				break;
+	size_t n, head;
+
+	head = ldata->read_head & (N_TTY_BUF_SIZE - 1);
+	n = N_TTY_BUF_SIZE - max(read_cnt(ldata), head);
+	n = min_t(size_t, count, n);
+	memcpy(read_buf_addr(ldata, head), cp, n);
+	ldata->read_head += n;
+	cp += n;
+	count -= n;
+
+	head = ldata->read_head & (N_TTY_BUF_SIZE - 1);
+	n = N_TTY_BUF_SIZE - max(read_cnt(ldata), head);
+	n = min_t(size_t, count, n);
+	memcpy(read_buf_addr(ldata, head), cp, n);
+	ldata->read_head += n;
+}
+
+static void
+n_tty_receive_buf_raw(struct tty_struct *tty, const unsigned char *cp,
+		      char *fp, int count)
+{
+	struct n_tty_data *ldata = tty->disc_data;
+	char flag = TTY_NORMAL;
+
+	while (count--) {
+		if (fp)
+			flag = *fp++;
+		if (likely(flag == TTY_NORMAL))
+			put_tty_queue(*cp++, ldata);
+		else
+			n_tty_receive_char_flagged(tty, *cp++, flag);
+	}
+}
+
+static void
+n_tty_receive_buf_closing(struct tty_struct *tty, const unsigned char *cp,
+			  char *fp, int count)
+{
+	char flag = TTY_NORMAL;
+
+	while (count--) {
+		if (fp)
+			flag = *fp++;
+		if (likely(flag == TTY_NORMAL))
+			n_tty_receive_char_closing(tty, *cp++);
+		else
+			n_tty_receive_char_flagged(tty, *cp++, flag);
+	}
+}
+
+static void
+n_tty_receive_buf_standard(struct tty_struct *tty, const unsigned char *cp,
+			  char *fp, int count)
+{
+	struct n_tty_data *ldata = tty->disc_data;
+	char flag = TTY_NORMAL;
+
+	while (count--) {
+		if (fp)
+			flag = *fp++;
+		if (likely(flag == TTY_NORMAL)) {
+			unsigned char c = *cp++;
+
+			if (I_ISTRIP(tty))
+				c &= 0x7f;
+			if (I_IUCLC(tty) && L_IEXTEN(tty))
+				c = tolower(c);
+			if (L_EXTPROC(tty)) {
+				put_tty_queue(c, ldata);
+				continue;
 			}
+			if (!test_bit(c, ldata->char_map))
+				n_tty_receive_char_inline(tty, c);
+			else if (n_tty_receive_char_special(tty, c) && count) {
+				if (fp)
+					flag = *fp++;
+				n_tty_receive_char_lnext(tty, *cp++, flag);
+				count--;
+			}
+		} else
+			n_tty_receive_char_flagged(tty, *cp++, flag);
+	}
+}
+
+static void
+n_tty_receive_buf_fast(struct tty_struct *tty, const unsigned char *cp,
+		       char *fp, int count)
+{
+	struct n_tty_data *ldata = tty->disc_data;
+	char flag = TTY_NORMAL;
+
+	while (count--) {
+		if (fp)
+			flag = *fp++;
+		if (likely(flag == TTY_NORMAL)) {
+			unsigned char c = *cp++;
+
+			if (!test_bit(c, ldata->char_map))
+				n_tty_receive_char_fast(tty, c);
+			else if (n_tty_receive_char_special(tty, c) && count) {
+				if (fp)
+					flag = *fp++;
+				n_tty_receive_char_lnext(tty, *cp++, flag);
+				count--;
+			}
+		} else
+			n_tty_receive_char_flagged(tty, *cp++, flag);
+	}
+}
+
+static void __receive_buf(struct tty_struct *tty, const unsigned char *cp,
+			  char *fp, int count)
+{
+	struct n_tty_data *ldata = tty->disc_data;
+	bool preops = I_ISTRIP(tty) || (I_IUCLC(tty) && L_IEXTEN(tty));
+
+	if (ldata->real_raw)
+		n_tty_receive_buf_real_raw(tty, cp, fp, count);
+	else if (ldata->raw || (L_EXTPROC(tty) && !preops))
+		n_tty_receive_buf_raw(tty, cp, fp, count);
+	else if (tty->closing && !L_EXTPROC(tty))
+		n_tty_receive_buf_closing(tty, cp, fp, count);
+	else {
+		if (ldata->lnext) {
+			char flag = TTY_NORMAL;
+
+			if (fp)
+				flag = *fp++;
+			n_tty_receive_char_lnext(tty, *cp++, flag);
+			count--;
 		}
+
+		if (!preops && !I_PARMRK(tty))
+			n_tty_receive_buf_fast(tty, cp, fp, count);
+		else
+			n_tty_receive_buf_standard(tty, cp, fp, count);
+
+		flush_echoes(tty);
 		if (tty->ops->flush_chars)
 			tty->ops->flush_chars(tty);
 	}
 
-	set_room(tty);
-
-	if ((!ldata->icanon && (ldata->read_cnt >= ldata->minimum_to_wake)) ||
+	if ((!ldata->icanon && (read_cnt(ldata) >= ldata->minimum_to_wake)) ||
 		L_EXTPROC(tty)) {
 		kill_fasync(&tty->fasync, SIGIO, POLL_IN);
 		if (waitqueue_active(&tty->read_wait))
 			wake_up_interruptible(&tty->read_wait);
 	}
+}
+
+static void n_tty_receive_buf(struct tty_struct *tty, const unsigned char *cp,
+			      char *fp, int count)
+{
+	int room, n;
+
+	down_read(&tty->termios_rwsem);
 
-	/*
-	 * Check the remaining room for the input canonicalization
-	 * mode.  We don't want to throttle the driver if we're in
-	 * canonical mode and don't have a newline yet!
-	 */
 	while (1) {
-		tty_set_flow_change(tty, TTY_THROTTLE_SAFE);
-		if (tty->receive_room >= TTY_THRESHOLD_THROTTLE)
+		room = receive_room(tty);
+		n = min(count, room);
+		if (!n)
 			break;
-		if (!tty_throttle_safe(tty))
+		__receive_buf(tty, cp, fp, n);
+		cp += n;
+		if (fp)
+			fp += n;
+		count -= n;
+	}
+
+	tty->receive_room = room;
+	n_tty_check_throttle(tty);
+	up_read(&tty->termios_rwsem);
+}
+
+static int n_tty_receive_buf2(struct tty_struct *tty, const unsigned char *cp,
+			      char *fp, int count)
+{
+	struct n_tty_data *ldata = tty->disc_data;
+	int room, n, rcvd = 0;
+
+	down_read(&tty->termios_rwsem);
+
+	while (1) {
+		room = receive_room(tty);
+		n = min(count, room);
+		if (!n) {
+			if (!room)
+				ldata->no_room = 1;
 			break;
+		}
+		__receive_buf(tty, cp, fp, n);
+		cp += n;
+		if (fp)
+			fp += n;
+		count -= n;
+		rcvd += n;
 	}
-	__tty_set_flow_change(tty, 0);
+
+	tty->receive_room = room;
+	n_tty_check_throttle(tty);
+	up_read(&tty->termios_rwsem);
+
+	return rcvd;
 }
 
 int is_ignored(int sig)
@@ -1505,7 +1746,7 @@ int is_ignored(int sig)
  *	guaranteed that this function will not be re-entered or in progress
  *	when the ldisc is closed.
  *
- *	Locking: Caller holds tty->termios_mutex
+ *	Locking: Caller holds tty->termios_rwsem
  */
 
 static void n_tty_set_termios(struct tty_struct *tty, struct ktermios *old)
@@ -1517,12 +1758,13 @@ static void n_tty_set_termios(struct tty_struct *tty, struct ktermios *old)
 		canon_change = (old->c_lflag ^ tty->termios.c_lflag) & ICANON;
 	if (canon_change) {
 		bitmap_zero(ldata->read_flags, N_TTY_BUF_SIZE);
+		ldata->line_start = 0;
 		ldata->canon_head = ldata->read_tail;
-		ldata->canon_data = 0;
 		ldata->erasing = 0;
+		ldata->lnext = 0;
 	}
 
-	if (canon_change && !L_ICANON(tty) && ldata->read_cnt)
+	if (canon_change && !L_ICANON(tty) && read_cnt(ldata))
 		wake_up_interruptible(&tty->read_wait);
 
 	ldata->icanon = (L_ICANON(tty) != 0);
@@ -1531,41 +1773,38 @@ static void n_tty_set_termios(struct tty_struct *tty, struct ktermios *old)
 	    I_ICRNL(tty) || I_INLCR(tty) || L_ICANON(tty) ||
 	    I_IXON(tty) || L_ISIG(tty) || L_ECHO(tty) ||
 	    I_PARMRK(tty)) {
-		bitmap_zero(ldata->process_char_map, 256);
+		bitmap_zero(ldata->char_map, 256);
 
 		if (I_IGNCR(tty) || I_ICRNL(tty))
-			set_bit('\r', ldata->process_char_map);
+			set_bit('\r', ldata->char_map);
 		if (I_INLCR(tty))
-			set_bit('\n', ldata->process_char_map);
+			set_bit('\n', ldata->char_map);
 
 		if (L_ICANON(tty)) {
-			set_bit(ERASE_CHAR(tty), ldata->process_char_map);
-			set_bit(KILL_CHAR(tty), ldata->process_char_map);
-			set_bit(EOF_CHAR(tty), ldata->process_char_map);
-			set_bit('\n', ldata->process_char_map);
-			set_bit(EOL_CHAR(tty), ldata->process_char_map);
+			set_bit(ERASE_CHAR(tty), ldata->char_map);
+			set_bit(KILL_CHAR(tty), ldata->char_map);
+			set_bit(EOF_CHAR(tty), ldata->char_map);
+			set_bit('\n', ldata->char_map);
+			set_bit(EOL_CHAR(tty), ldata->char_map);
 			if (L_IEXTEN(tty)) {
-				set_bit(WERASE_CHAR(tty),
-					ldata->process_char_map);
-				set_bit(LNEXT_CHAR(tty),
-					ldata->process_char_map);
-				set_bit(EOL2_CHAR(tty),
-					ldata->process_char_map);
+				set_bit(WERASE_CHAR(tty), ldata->char_map);
+				set_bit(LNEXT_CHAR(tty), ldata->char_map);
+				set_bit(EOL2_CHAR(tty), ldata->char_map);
 				if (L_ECHO(tty))
 					set_bit(REPRINT_CHAR(tty),
-						ldata->process_char_map);
+						ldata->char_map);
 			}
 		}
 		if (I_IXON(tty)) {
-			set_bit(START_CHAR(tty), ldata->process_char_map);
-			set_bit(STOP_CHAR(tty), ldata->process_char_map);
+			set_bit(START_CHAR(tty), ldata->char_map);
+			set_bit(STOP_CHAR(tty), ldata->char_map);
 		}
 		if (L_ISIG(tty)) {
-			set_bit(INTR_CHAR(tty), ldata->process_char_map);
-			set_bit(QUIT_CHAR(tty), ldata->process_char_map);
-			set_bit(SUSP_CHAR(tty), ldata->process_char_map);
+			set_bit(INTR_CHAR(tty), ldata->char_map);
+			set_bit(QUIT_CHAR(tty), ldata->char_map);
+			set_bit(SUSP_CHAR(tty), ldata->char_map);
 		}
-		clear_bit(__DISABLED_CHAR, ldata->process_char_map);
+		clear_bit(__DISABLED_CHAR, ldata->char_map);
 		ldata->raw = 0;
 		ldata->real_raw = 0;
 	} else {
@@ -1608,9 +1847,7 @@ static void n_tty_close(struct tty_struct *tty)
 	if (tty->link)
 		n_tty_packet_mode_flush(tty);
 
-	kfree(ldata->read_buf);
-	kfree(ldata->echo_buf);
-	kfree(ldata);
+	vfree(ldata);
 	tty->disc_data = NULL;
 }
 
@@ -1628,26 +1865,23 @@ static int n_tty_open(struct tty_struct *tty)
 {
 	struct n_tty_data *ldata;
 
-	ldata = kzalloc(sizeof(*ldata), GFP_KERNEL);
+	/* Currently a malloc failure here can panic */
+	ldata = vmalloc(sizeof(*ldata));
 	if (!ldata)
 		goto err;
 
 	ldata->overrun_time = jiffies;
 	mutex_init(&ldata->atomic_read_lock);
 	mutex_init(&ldata->output_lock);
-	mutex_init(&ldata->echo_lock);
-	raw_spin_lock_init(&ldata->read_lock);
-
-	/* These are ugly. Currently a malloc failure here can panic */
-	ldata->read_buf = kzalloc(N_TTY_BUF_SIZE, GFP_KERNEL);
-	ldata->echo_buf = kzalloc(N_TTY_BUF_SIZE, GFP_KERNEL);
-	if (!ldata->read_buf || !ldata->echo_buf)
-		goto err_free_bufs;
 
 	tty->disc_data = ldata;
 	reset_buffer_flags(tty->disc_data);
 	ldata->column = 0;
+	ldata->canon_column = 0;
 	ldata->minimum_to_wake = 1;
+	ldata->num_overrun = 0;
+	ldata->no_room = 0;
+	ldata->lnext = 0;
 	tty->closing = 0;
 	/* indicate buffer work may resume */
 	clear_bit(TTY_LDISC_HALTED, &tty->flags);
@@ -1655,10 +1889,6 @@ static int n_tty_open(struct tty_struct *tty)
 	tty_unthrottle(tty);
 
 	return 0;
-err_free_bufs:
-	kfree(ldata->read_buf);
-	kfree(ldata->echo_buf);
-	kfree(ldata);
 err:
 	return -ENOMEM;
 }
@@ -1667,11 +1897,10 @@ static inline int input_available_p(struct tty_struct *tty, int amt)
 {
 	struct n_tty_data *ldata = tty->disc_data;
 
-	tty_flush_to_ldisc(tty);
 	if (ldata->icanon && !L_EXTPROC(tty)) {
-		if (ldata->canon_data)
+		if (ldata->canon_head != ldata->read_tail)
 			return 1;
-	} else if (ldata->read_cnt >= (amt ? amt : 1))
+	} else if (read_cnt(ldata) >= (amt ? amt : 1))
 		return 1;
 
 	return 0;
@@ -1692,6 +1921,9 @@ static inline int input_available_p(struct tty_struct *tty, int amt)
  *
  *	Called under the ldata->atomic_read_lock sem
  *
+ *	n_tty_read()/consumer path:
+ *		caller holds non-exclusive termios_rwsem
+ *		read_tail published
  */
 
 static int copy_from_read_buf(struct tty_struct *tty,
@@ -1702,34 +1934,114 @@ static int copy_from_read_buf(struct tty_struct *tty,
 	struct n_tty_data *ldata = tty->disc_data;
 	int retval;
 	size_t n;
-	unsigned long flags;
 	bool is_eof;
+	size_t tail = ldata->read_tail & (N_TTY_BUF_SIZE - 1);
 
 	retval = 0;
-	raw_spin_lock_irqsave(&ldata->read_lock, flags);
-	n = min(ldata->read_cnt, N_TTY_BUF_SIZE - ldata->read_tail);
+	n = min(read_cnt(ldata), N_TTY_BUF_SIZE - tail);
 	n = min(*nr, n);
-	raw_spin_unlock_irqrestore(&ldata->read_lock, flags);
 	if (n) {
-		retval = copy_to_user(*b, &ldata->read_buf[ldata->read_tail], n);
+		retval = copy_to_user(*b, read_buf_addr(ldata, tail), n);
 		n -= retval;
-		is_eof = n == 1 &&
-			ldata->read_buf[ldata->read_tail] == EOF_CHAR(tty);
-		tty_audit_add_data(tty, &ldata->read_buf[ldata->read_tail], n,
+		is_eof = n == 1 && read_buf(ldata, tail) == EOF_CHAR(tty);
+		tty_audit_add_data(tty, read_buf_addr(ldata, tail), n,
 				ldata->icanon);
-		raw_spin_lock_irqsave(&ldata->read_lock, flags);
-		ldata->read_tail = (ldata->read_tail + n) & (N_TTY_BUF_SIZE-1);
-		ldata->read_cnt -= n;
+		ldata->read_tail += n;
 		/* Turn single EOF into zero-length read */
-		if (L_EXTPROC(tty) && ldata->icanon && is_eof && !ldata->read_cnt)
+		if (L_EXTPROC(tty) && ldata->icanon && is_eof && !read_cnt(ldata))
 			n = 0;
-		raw_spin_unlock_irqrestore(&ldata->read_lock, flags);
 		*b += n;
 		*nr -= n;
 	}
 	return retval;
 }
 
+/**
+ *	canon_copy_from_read_buf	-	copy read data in canonical mode
+ *	@tty: terminal device
+ *	@b: user data
+ *	@nr: size of data
+ *
+ *	Helper function for n_tty_read.  It is only called when ICANON is on;
+ *	it copies one line of input up to and including the line-delimiting
+ *	character into the user-space buffer.
+ *
+ *	Called under the atomic_read_lock mutex
+ *
+ *	n_tty_read()/consumer path:
+ *		caller holds non-exclusive termios_rwsem
+ *		read_tail published
+ */
+
+static int canon_copy_from_read_buf(struct tty_struct *tty,
+				    unsigned char __user **b,
+				    size_t *nr)
+{
+	struct n_tty_data *ldata = tty->disc_data;
+	size_t n, size, more, c;
+	size_t eol;
+	size_t tail;
+	int ret, found = 0;
+	bool eof_push = 0;
+
+	/* N.B. avoid overrun if nr == 0 */
+	n = min(*nr, read_cnt(ldata));
+	if (!n)
+		return 0;
+
+	tail = ldata->read_tail & (N_TTY_BUF_SIZE - 1);
+	size = min_t(size_t, tail + n, N_TTY_BUF_SIZE);
+
+	n_tty_trace("%s: nr:%zu tail:%zu n:%zu size:%zu\n",
+		    __func__, *nr, tail, n, size);
+
+	eol = find_next_bit(ldata->read_flags, size, tail);
+	more = n - (size - tail);
+	if (eol == N_TTY_BUF_SIZE && more) {
+		/* scan wrapped without finding set bit */
+		eol = find_next_bit(ldata->read_flags, more, 0);
+		if (eol != more)
+			found = 1;
+	} else if (eol != size)
+		found = 1;
+
+	size = N_TTY_BUF_SIZE - tail;
+	n = (found + eol + size) & (N_TTY_BUF_SIZE - 1);
+	c = n;
+
+	if (found && read_buf(ldata, eol) == __DISABLED_CHAR) {
+		n--;
+		eof_push = !n && ldata->read_tail != ldata->line_start;
+	}
+
+	n_tty_trace("%s: eol:%zu found:%d n:%zu c:%zu size:%zu more:%zu\n",
+		    __func__, eol, found, n, c, size, more);
+
+	if (n > size) {
+		ret = copy_to_user(*b, read_buf_addr(ldata, tail), size);
+		if (ret)
+			return -EFAULT;
+		ret = copy_to_user(*b + size, ldata->read_buf, n - size);
+	} else
+		ret = copy_to_user(*b, read_buf_addr(ldata, tail), n);
+
+	if (ret)
+		return -EFAULT;
+	*b += n;
+	*nr -= n;
+
+	if (found)
+		clear_bit(eol, ldata->read_flags);
+	smp_mb__after_clear_bit();
+	ldata->read_tail += c;
+
+	if (found) {
+		ldata->line_start = ldata->read_tail;
+		tty_audit_push(tty);
+	}
+	return eof_push ? -EAGAIN : 0;
+}
+
 extern ssize_t redirected_tty_write(struct file *, const char __user *,
 							size_t, loff_t *);
 
@@ -1787,6 +2099,10 @@ static int job_control(struct tty_struct *tty, struct file *file)
  *	a hangup. Always called in user context, may sleep.
  *
  *	This code must be sure never to sleep through a hangup.
+ *
+ *	n_tty_read()/consumer path:
+ *		claims non-exclusive termios_rwsem
+ *		publishes read_tail
  */
 
 static ssize_t n_tty_read(struct tty_struct *tty, struct file *file,
@@ -1798,16 +2114,27 @@ static ssize_t n_tty_read(struct tty_struct *tty, struct file *file,
 	int c;
 	int minimum, time;
 	ssize_t retval = 0;
-	ssize_t size;
 	long timeout;
 	unsigned long flags;
 	int packet;
 
-do_it_again:
 	c = job_control(tty, file);
 	if (c < 0)
 		return c;
 
+	/*
+	 *	Internal serialization of reads.
+	 */
+	if (file->f_flags & O_NONBLOCK) {
+		if (!mutex_trylock(&ldata->atomic_read_lock))
+			return -EAGAIN;
+	} else {
+		if (mutex_lock_interruptible(&ldata->atomic_read_lock))
+			return -ERESTARTSYS;
+	}
+
+	down_read(&tty->termios_rwsem);
+
 	minimum = time = 0;
 	timeout = MAX_SCHEDULE_TIMEOUT;
 	if (!ldata->icanon) {
@@ -1825,16 +2152,6 @@ do_it_again:
 		}
 	}
 
-	/*
-	 *	Internal serialization of reads.
-	 */
-	if (file->f_flags & O_NONBLOCK) {
-		if (!mutex_trylock(&ldata->atomic_read_lock))
-			return -EAGAIN;
-	} else {
-		if (mutex_lock_interruptible(&ldata->atomic_read_lock))
-			return -ERESTARTSYS;
-	}
 	packet = tty->packet;
 
 	add_wait_queue(&tty->read_wait, &wait);
@@ -1883,7 +2200,11 @@ do_it_again:
 				break;
 			}
 			n_tty_set_room(tty);
+			up_read(&tty->termios_rwsem);
+
 			timeout = schedule_timeout(timeout);
+
+			down_read(&tty->termios_rwsem);
 			continue;
 		}
 		__set_current_state(TASK_RUNNING);
@@ -1899,45 +2220,11 @@ do_it_again:
 		}
 
 		if (ldata->icanon && !L_EXTPROC(tty)) {
-			/* N.B. avoid overrun if nr == 0 */
-			raw_spin_lock_irqsave(&ldata->read_lock, flags);
-			while (nr && ldata->read_cnt) {
-				int eol;
-
-				eol = test_and_clear_bit(ldata->read_tail,
-						ldata->read_flags);
-				c = ldata->read_buf[ldata->read_tail];
-				ldata->read_tail = ((ldata->read_tail+1) &
-						  (N_TTY_BUF_SIZE-1));
-				ldata->read_cnt--;
-				if (eol) {
-					/* this test should be redundant:
-					 * we shouldn't be reading data if
-					 * canon_data is 0
-					 */
-					if (--ldata->canon_data < 0)
-						ldata->canon_data = 0;
-				}
-				raw_spin_unlock_irqrestore(&ldata->read_lock, flags);
-
-				if (!eol || (c != __DISABLED_CHAR)) {
-					if (tty_put_user(tty, c, b++)) {
-						retval = -EFAULT;
-						b--;
-						raw_spin_lock_irqsave(&ldata->read_lock, flags);
-						break;
-					}
-					nr--;
-				}
-				if (eol) {
-					tty_audit_push(tty);
-					raw_spin_lock_irqsave(&ldata->read_lock, flags);
-					break;
-				}
-				raw_spin_lock_irqsave(&ldata->read_lock, flags);
-			}
-			raw_spin_unlock_irqrestore(&ldata->read_lock, flags);
-			if (retval)
+			retval = canon_copy_from_read_buf(tty, &b, &nr);
+			if (retval == -EAGAIN) {
+				retval = 0;
+				continue;
+			} else if (retval)
 				break;
 		} else {
 			int uncopied;
@@ -1951,24 +2238,7 @@ do_it_again:
 			}
 		}
 
-		/* If there is enough space in the read buffer now, let the
-		 * low-level driver know. We use n_tty_chars_in_buffer() to
-		 * check the buffer, as it now knows about canonical mode.
-		 * Otherwise, if the driver is throttled and the line is
-		 * longer than TTY_THRESHOLD_UNTHROTTLE in canonical mode,
-		 * we won't get any more characters.
-		 */
-		while (1) {
-			tty_set_flow_change(tty, TTY_UNTHROTTLE_SAFE);
-			if (n_tty_chars_in_buffer(tty) > TTY_THRESHOLD_UNTHROTTLE)
-				break;
-			if (!tty->count)
-				break;
-			n_tty_set_room(tty);
-			if (!tty_unthrottle_safe(tty))
-				break;
-		}
-		__tty_set_flow_change(tty, 0);
+		n_tty_check_unthrottle(tty);
 
 		if (b - buf >= minimum)
 			break;
@@ -1982,15 +2252,11 @@ do_it_again:
 		ldata->minimum_to_wake = minimum;
 
 	__set_current_state(TASK_RUNNING);
-	size = b - buf;
-	if (size) {
-		retval = size;
-		if (nr)
-			clear_bit(TTY_PUSH, &tty->flags);
-	} else if (test_and_clear_bit(TTY_PUSH, &tty->flags))
-		goto do_it_again;
+	if (b - buf)
+		retval = b - buf;
 
 	n_tty_set_room(tty);
+	up_read(&tty->termios_rwsem);
 	return retval;
 }
 
@@ -2031,6 +2297,8 @@ static ssize_t n_tty_write(struct tty_struct *tty, struct file *file,
 			return retval;
 	}
 
+	down_read(&tty->termios_rwsem);
+
 	/* Write out any echoed characters that are still pending */
 	process_echoes(tty);
 
@@ -2084,13 +2352,18 @@ static ssize_t n_tty_write(struct tty_struct *tty, struct file *file,
 			retval = -EAGAIN;
 			break;
 		}
+		up_read(&tty->termios_rwsem);
+
 		schedule();
+
+		down_read(&tty->termios_rwsem);
 	}
 break_out:
 	__set_current_state(TASK_RUNNING);
 	remove_wait_queue(&tty->write_wait, &wait);
 	if (b - buf != nr && tty->fasync)
 		set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
+	up_read(&tty->termios_rwsem);
 	return (b - buf) ? b - buf : retval;
 }
 
@@ -2139,19 +2412,19 @@ static unsigned int n_tty_poll(struct tty_struct *tty, struct file *file,
 
 static unsigned long inq_canon(struct n_tty_data *ldata)
 {
-	int nr, head, tail;
+	size_t nr, head, tail;
 
-	if (!ldata->canon_data)
+	if (ldata->canon_head == ldata->read_tail)
 		return 0;
 	head = ldata->canon_head;
 	tail = ldata->read_tail;
-	nr = (head - tail) & (N_TTY_BUF_SIZE-1);
+	nr = head - tail;
 	/* Skip EOF-chars.. */
 	while (head != tail) {
-		if (test_bit(tail, ldata->read_flags) &&
-		    ldata->read_buf[tail] == __DISABLED_CHAR)
+		if (test_bit(tail & (N_TTY_BUF_SIZE - 1), ldata->read_flags) &&
+		    read_buf(ldata, tail) == __DISABLED_CHAR)
 			nr--;
-		tail = (tail+1) & (N_TTY_BUF_SIZE-1);
+		tail++;
 	}
 	return nr;
 }
@@ -2166,10 +2439,12 @@ static int n_tty_ioctl(struct tty_struct *tty, struct file *file,
 	case TIOCOUTQ:
 		return put_user(tty_chars_in_buffer(tty), (int __user *) arg);
 	case TIOCINQ:
-		/* FIXME: Locking */
-		retval = ldata->read_cnt;
+		down_write(&tty->termios_rwsem);
 		if (L_ICANON(tty))
 			retval = inq_canon(ldata);
+		else
+			retval = read_cnt(ldata);
+		up_write(&tty->termios_rwsem);
 		return put_user(retval, (unsigned int __user *) arg);
 	default:
 		return n_tty_ioctl_helper(tty, file, cmd, arg);
@@ -2203,6 +2478,7 @@ struct tty_ldisc_ops tty_ldisc_N_TTY = {
 	.receive_buf     = n_tty_receive_buf,
 	.write_wakeup    = n_tty_write_wakeup,
 	.fasync		 = n_tty_fasync,
+	.receive_buf2	 = n_tty_receive_buf2,
 };
 
 /**
diff --git a/drivers/tty/pty.c b/drivers/tty/pty.c
index abfd9908978..25c9bc78372 100644
--- a/drivers/tty/pty.c
+++ b/drivers/tty/pty.c
@@ -89,17 +89,13 @@ static void pty_unthrottle(struct tty_struct *tty)
  *	pty_space	-	report space left for writing
  *	@to: tty we are writing into
  *
- *	The tty buffers allow 64K but we sneak a peak and clip at 8K this
- *	allows a lot of overspill room for echo and other fun messes to
- *	be handled properly
+ *	Limit the buffer space used by ptys to 8k.
  */
 
 static int pty_space(struct tty_struct *to)
 {
-	int n = 8192 - to->port->buf.memory_used;
-	if (n < 0)
-		return 0;
-	return n;
+	int n = tty_buffer_space_avail(to->port);
+	return min(n, 8192);
 }
 
 /**
@@ -125,10 +121,8 @@ static int pty_write(struct tty_struct *tty, const unsigned char *buf, int c)
 		/* Stuff the data into the input queue of the other end */
 		c = tty_insert_flip_string(to->port, buf, c);
 		/* And shovel */
-		if (c) {
+		if (c)
 			tty_flip_buffer_push(to->port);
-			tty_wakeup(tty);
-		}
 	}
 	return c;
 }
@@ -287,7 +281,7 @@ static int pty_resize(struct tty_struct *tty,  struct winsize *ws)
 	struct tty_struct *pty = tty->link;
 
 	/* For a PTY we need to lock the tty side */
-	mutex_lock(&tty->termios_mutex);
+	mutex_lock(&tty->winsize_mutex);
 	if (!memcmp(ws, &tty->winsize, sizeof(*ws)))
 		goto done;
 
@@ -314,7 +308,7 @@ static int pty_resize(struct tty_struct *tty,  struct winsize *ws)
 	tty->winsize = *ws;
 	pty->winsize = *ws;	/* Never used so will go away soon */
 done:
-	mutex_unlock(&tty->termios_mutex);
+	mutex_unlock(&tty->winsize_mutex);
 	return 0;
 }
 
diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c
index 86c00b1c558..570df9d2a5d 100644
--- a/drivers/tty/serial/8250/8250_core.c
+++ b/drivers/tty/serial/8250/8250_core.c
@@ -3062,7 +3062,7 @@ void serial8250_resume_port(int line)
  */
 static int serial8250_probe(struct platform_device *dev)
 {
-	struct plat_serial8250_port *p = dev->dev.platform_data;
+	struct plat_serial8250_port *p = dev_get_platdata(&dev->dev);
 	struct uart_8250_port uart;
 	int ret, i, irqflag = 0;
 
diff --git a/drivers/tty/serial/8250/8250_dw.c b/drivers/tty/serial/8250/8250_dw.c
index 76a8daadff4..daf710f5c3f 100644
--- a/drivers/tty/serial/8250/8250_dw.c
+++ b/drivers/tty/serial/8250/8250_dw.c
@@ -57,11 +57,25 @@
 
 struct dw8250_data {
 	int		last_lcr;
+	int		last_mcr;
 	int		line;
 	struct clk	*clk;
 	u8		usr_reg;
 };
 
+static inline int dw8250_modify_msr(struct uart_port *p, int offset, int value)
+{
+	struct dw8250_data *d = p->private_data;
+
+	/* If reading MSR, report CTS asserted when auto-CTS/RTS enabled */
+	if (offset == UART_MSR && d->last_mcr & UART_MCR_AFE) {
+		value |= UART_MSR_CTS;
+		value &= ~UART_MSR_DCTS;
+	}
+
+	return value;
+}
+
 static void dw8250_serial_out(struct uart_port *p, int offset, int value)
 {
 	struct dw8250_data *d = p->private_data;
@@ -69,15 +83,17 @@ static void dw8250_serial_out(struct uart_port *p, int offset, int value)
 	if (offset == UART_LCR)
 		d->last_lcr = value;
 
-	offset <<= p->regshift;
-	writeb(value, p->membase + offset);
+	if (offset == UART_MCR)
+		d->last_mcr = value;
+
+	writeb(value, p->membase + (offset << p->regshift));
 }
 
 static unsigned int dw8250_serial_in(struct uart_port *p, int offset)
 {
-	offset <<= p->regshift;
+	unsigned int value = readb(p->membase + (offset << p->regshift));
 
-	return readb(p->membase + offset);
+	return dw8250_modify_msr(p, offset, value);
 }
 
 /* Read Back (rb) version to ensure register access ording. */
@@ -94,15 +110,17 @@ static void dw8250_serial_out32(struct uart_port *p, int offset, int value)
 	if (offset == UART_LCR)
 		d->last_lcr = value;
 
-	offset <<= p->regshift;
-	writel(value, p->membase + offset);
+	if (offset == UART_MCR)
+		d->last_mcr = value;
+
+	writel(value, p->membase + (offset << p->regshift));
 }
 
 static unsigned int dw8250_serial_in32(struct uart_port *p, int offset)
 {
-	offset <<= p->regshift;
+	unsigned int value = readl(p->membase + (offset << p->regshift));
 
-	return readl(p->membase + offset);
+	return dw8250_modify_msr(p, offset, value);
 }
 
 static int dw8250_handle_irq(struct uart_port *p)
diff --git a/drivers/tty/serial/8250/8250_early.c b/drivers/tty/serial/8250/8250_early.c
index 946ddd2b3a5..c100d6343d5 100644
--- a/drivers/tty/serial/8250/8250_early.c
+++ b/drivers/tty/serial/8250/8250_early.c
@@ -194,7 +194,7 @@ static int __init parse_options(struct early_serial8250_device *device,
 		options++;
 		device->baud = simple_strtoul(options, NULL, 0);
 		length = min(strcspn(options, " ") + 1,
-			     sizeof(device->options));
+			     (size_t)(sizeof(device->options)));
 		strlcpy(device->options, options, length);
 	} else {
 		device->baud = probe_baud(port);
diff --git a/drivers/tty/serial/8250/8250_em.c b/drivers/tty/serial/8250/8250_em.c
index 916cc19fbbd..5f3bba12c15 100644
--- a/drivers/tty/serial/8250/8250_em.c
+++ b/drivers/tty/serial/8250/8250_em.c
@@ -95,25 +95,23 @@ static int serial8250_em_probe(struct platform_device *pdev)
 	struct resource *irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
 	struct serial8250_em_priv *priv;
 	struct uart_8250_port up;
-	int ret = -EINVAL;
+	int ret;
 
 	if (!regs || !irq) {
 		dev_err(&pdev->dev, "missing registers or irq\n");
-		goto err0;
+		return -EINVAL;
 	}
 
-	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
 	if (!priv) {
 		dev_err(&pdev->dev, "unable to allocate private data\n");
-		ret = -ENOMEM;
-		goto err0;
+		return -ENOMEM;
 	}
 
-	priv->sclk = clk_get(&pdev->dev, "sclk");
+	priv->sclk = devm_clk_get(&pdev->dev, "sclk");
 	if (IS_ERR(priv->sclk)) {
 		dev_err(&pdev->dev, "unable to get clock\n");
-		ret = PTR_ERR(priv->sclk);
-		goto err1;
+		return PTR_ERR(priv->sclk);
 	}
 
 	memset(&up, 0, sizeof(up));
@@ -136,20 +134,13 @@ static int serial8250_em_probe(struct platform_device *pdev)
 	ret = serial8250_register_8250_port(&up);
 	if (ret < 0) {
 		dev_err(&pdev->dev, "unable to register 8250 port\n");
-		goto err2;
+		clk_disable(priv->sclk);
+		return ret;
 	}
 
 	priv->line = ret;
 	platform_set_drvdata(pdev, priv);
 	return 0;
-
- err2:
-	clk_disable(priv->sclk);
-	clk_put(priv->sclk);
- err1:
-	kfree(priv);
- err0:
-	return ret;
 }
 
 static int serial8250_em_remove(struct platform_device *pdev)
@@ -158,8 +149,6 @@ static int serial8250_em_remove(struct platform_device *pdev)
 
 	serial8250_unregister_port(priv->line);
 	clk_disable(priv->sclk);
-	clk_put(priv->sclk);
-	kfree(priv);
 	return 0;
 }
 
diff --git a/drivers/tty/serial/8250/8250_pci.c b/drivers/tty/serial/8250/8250_pci.c
index c52948b368d..c810da7c7a8 100644
--- a/drivers/tty/serial/8250/8250_pci.c
+++ b/drivers/tty/serial/8250/8250_pci.c
@@ -1565,6 +1565,7 @@ pci_wch_ch353_setup(struct serial_private *priv,
 #define PCI_DEVICE_ID_COMMTECH_4228PCIE	0x0021
 #define PCI_DEVICE_ID_COMMTECH_4222PCIE	0x0022
 #define PCI_DEVICE_ID_BROADCOM_TRUMANAGE 0x160a
+#define PCI_DEVICE_ID_AMCC_ADDIDATA_APCI7800 0x818e
 
 #define PCI_VENDOR_ID_SUNIX		0x1fd4
 #define PCI_DEVICE_ID_SUNIX_1999	0x1999
@@ -1587,8 +1588,8 @@ static struct pci_serial_quirk pci_serial_quirks[] __refdata = {
 	* ADDI-DATA GmbH communication cards <info@addi-data.com>
 	*/
 	{
-		.vendor         = PCI_VENDOR_ID_ADDIDATA_OLD,
-		.device         = PCI_DEVICE_ID_ADDIDATA_APCI7800,
+		.vendor         = PCI_VENDOR_ID_AMCC,
+		.device         = PCI_DEVICE_ID_AMCC_ADDIDATA_APCI7800,
 		.subvendor      = PCI_ANY_ID,
 		.subdevice      = PCI_ANY_ID,
 		.setup          = addidata_apci7800_setup,
@@ -4697,8 +4698,8 @@ static struct pci_device_id serial_pci_tbl[] = {
 		0,
 		pbn_b0_1_115200 },
 
-	{	PCI_VENDOR_ID_ADDIDATA_OLD,
-		PCI_DEVICE_ID_ADDIDATA_APCI7800,
+	{	PCI_VENDOR_ID_AMCC,
+		PCI_DEVICE_ID_AMCC_ADDIDATA_APCI7800,
 		PCI_ANY_ID,
 		PCI_ANY_ID,
 		0,
@@ -4797,6 +4798,12 @@ static struct pci_device_id serial_pci_tbl[] = {
 		PCI_VENDOR_ID_IBM, 0x0299,
 		0, 0, pbn_b0_bt_2_115200 },
 
+	/*
+	 * other NetMos 9835 devices are most likely handled by the
+	 * parport_serial driver, check drivers/parport/parport_serial.c
+	 * before adding them here.
+	 */
+
 	{	PCI_VENDOR_ID_NETMOS, PCI_DEVICE_ID_NETMOS_9901,
 		0xA000, 0x1000,
 		0, 0, pbn_b0_1_115200 },
diff --git a/drivers/tty/serial/8250/Kconfig b/drivers/tty/serial/8250/Kconfig
index a1ba94d6488..f3b306efaa5 100644
--- a/drivers/tty/serial/8250/Kconfig
+++ b/drivers/tty/serial/8250/Kconfig
@@ -116,6 +116,8 @@ config SERIAL_8250_PCI
 	  This builds standard PCI serial support. You may be able to
 	  disable this feature if you only need legacy serial support.
 	  Saves about 9K.
+	  Note that serial ports on NetMos 9835 Multi-I/O cards are handled
+	  by the parport_serial driver, enabled with CONFIG_PARPORT_SERIAL.
 
 config SERIAL_8250_HP300
 	tristate
diff --git a/drivers/tty/serial/Kconfig b/drivers/tty/serial/Kconfig
index 1456673bcca..cc4c8682b47 100644
--- a/drivers/tty/serial/Kconfig
+++ b/drivers/tty/serial/Kconfig
@@ -291,13 +291,13 @@ config SERIAL_MAX3100
 
 config SERIAL_MAX310X
 	bool "MAX310X support"
-	depends on SPI
+	depends on SPI_MASTER
 	select SERIAL_CORE
-	select REGMAP_SPI if SPI
+	select REGMAP_SPI if SPI_MASTER
 	default n
 	help
 	  This selects support for an advanced UART from Maxim (Dallas).
-	  Supported ICs are MAX3107, MAX3108.
+	  Supported ICs are MAX3107, MAX3108, MAX3109, MAX14830.
 	  Each IC contains 128 words each of receive and transmit FIFO
 	  that can be controlled through I2C or high-speed SPI.
 
@@ -1401,13 +1401,16 @@ config SERIAL_XILINX_PS_UART_CONSOLE
 	  Enable a Xilinx PS UART port to be the system console.
 
 config SERIAL_AR933X
-	bool "AR933X serial port support"
-	depends on SOC_AR933X
+	tristate "AR933X serial port support"
+	depends on HAVE_CLK && SOC_AR933X
 	select SERIAL_CORE
 	help
 	  If you have an Atheros AR933X SOC based board and want to use the
 	  built-in UART of the SoC, say Y to this option.
 
+	  To compile this driver as a module, choose M here: the
+	  module will be called ar933x_uart.
+
 config SERIAL_AR933X_CONSOLE
 	bool "Console on AR933X serial port"
 	depends on SERIAL_AR933X=y
@@ -1424,8 +1427,8 @@ config SERIAL_AR933X_NR_UARTS
 	  to support.
 
 config SERIAL_EFM32_UART
-	tristate "EFM32 UART/USART port."
-	depends on ARCH_EFM32
+	tristate "EFM32 UART/USART port"
+	depends on ARM && (ARCH_EFM32 || COMPILE_TEST)
 	select SERIAL_CORE
 	help
 	  This driver support the USART and UART ports on
@@ -1497,6 +1500,22 @@ config SERIAL_FSL_LPUART_CONSOLE
 	  If you have enabled the lpuart serial port on the Freescale SoCs,
 	  you can make it the console by answering Y to this option.
 
+config SERIAL_ST_ASC
+	tristate "ST ASC serial port support"
+	select SERIAL_CORE
+	help
+	  This driver is for the on-chip Asychronous Serial Controller on
+	  STMicroelectronics STi SoCs.
+	  ASC is embedded in ST COMMS IP block. It supports Rx & Tx functionality.
+	  It support all industry standard baud rates.
+
+	  If unsure, say N.
+
+config SERIAL_ST_ASC_CONSOLE
+	bool "Support for console on ST ASC"
+	depends on SERIAL_ST_ASC=y
+	select SERIAL_CORE_CONSOLE
+
 endmenu
 
 endif # TTY
diff --git a/drivers/tty/serial/Makefile b/drivers/tty/serial/Makefile
index cf650f0cd6e..47b679c547e 100644
--- a/drivers/tty/serial/Makefile
+++ b/drivers/tty/serial/Makefile
@@ -65,6 +65,7 @@ obj-$(CONFIG_SERIAL_KGDB_NMI) += kgdb_nmi.o
 obj-$(CONFIG_SERIAL_KS8695) += serial_ks8695.o
 obj-$(CONFIG_SERIAL_OMAP) += omap-serial.o
 obj-$(CONFIG_SERIAL_ALTERA_UART) += altera_uart.o
+obj-$(CONFIG_SERIAL_ST_ASC) += st-asc.o
 obj-$(CONFIG_KGDB_SERIAL_CONSOLE) += kgdboc.o
 obj-$(CONFIG_SERIAL_QE) += ucc_uart.o
 obj-$(CONFIG_SERIAL_TIMBERDALE)	+= timbuart.o
diff --git a/drivers/tty/serial/altera_jtaguart.c b/drivers/tty/serial/altera_jtaguart.c
index c6bdb943726..18e038fbdcd 100644
--- a/drivers/tty/serial/altera_jtaguart.c
+++ b/drivers/tty/serial/altera_jtaguart.c
@@ -139,7 +139,9 @@ static void altera_jtaguart_rx_chars(struct altera_jtaguart *pp)
 		uart_insert_char(port, 0, 0, ch, flag);
 	}
 
+	spin_unlock(&port->lock);
 	tty_flip_buffer_push(&port->state->port);
+	spin_lock(&port->lock);
 }
 
 static void altera_jtaguart_tx_chars(struct altera_jtaguart *pp)
@@ -408,7 +410,8 @@ static struct uart_driver altera_jtaguart_driver = {
 
 static int altera_jtaguart_probe(struct platform_device *pdev)
 {
-	struct altera_jtaguart_platform_uart *platp = pdev->dev.platform_data;
+	struct altera_jtaguart_platform_uart *platp =
+			dev_get_platdata(&pdev->dev);
 	struct uart_port *port;
 	struct resource *res_irq, *res_mem;
 	int i = pdev->id;
diff --git a/drivers/tty/serial/altera_uart.c b/drivers/tty/serial/altera_uart.c
index 1d46966e2a6..6431472aeb1 100644
--- a/drivers/tty/serial/altera_uart.c
+++ b/drivers/tty/serial/altera_uart.c
@@ -231,7 +231,9 @@ static void altera_uart_rx_chars(struct altera_uart *pp)
 				 flag);
 	}
 
+	spin_unlock(&port->lock);
 	tty_flip_buffer_push(&port->state->port);
+	spin_lock(&port->lock);
 }
 
 static void altera_uart_tx_chars(struct altera_uart *pp)
@@ -534,7 +536,7 @@ static int altera_uart_get_of_uartclk(struct platform_device *pdev,
 
 static int altera_uart_probe(struct platform_device *pdev)
 {
-	struct altera_uart_platform_uart *platp = pdev->dev.platform_data;
+	struct altera_uart_platform_uart *platp = dev_get_platdata(&pdev->dev);
 	struct uart_port *port;
 	struct resource *res_mem;
 	struct resource *res_irq;
diff --git a/drivers/tty/serial/amba-pl010.c b/drivers/tty/serial/amba-pl010.c
index c3684051952..8b90f0b6dfd 100644
--- a/drivers/tty/serial/amba-pl010.c
+++ b/drivers/tty/serial/amba-pl010.c
@@ -721,7 +721,7 @@ static int pl010_probe(struct amba_device *dev, const struct amba_id *id)
 	uap->port.flags = UPF_BOOT_AUTOCONF;
 	uap->port.line = i;
 	uap->dev = dev;
-	uap->data = dev->dev.platform_data;
+	uap->data = dev_get_platdata(&dev->dev);
 
 	amba_ports[i] = uap;
 
diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c
index 28b35ad9c6c..aaa22867e65 100644
--- a/drivers/tty/serial/amba-pl011.c
+++ b/drivers/tty/serial/amba-pl011.c
@@ -265,7 +265,7 @@ static void pl011_sgbuf_free(struct dma_chan *chan, struct pl011_sgbuf *sg,
 static void pl011_dma_probe_initcall(struct device *dev, struct uart_amba_port *uap)
 {
 	/* DMA is the sole user of the platform data right now */
-	struct amba_pl011_data *plat = uap->port.dev->platform_data;
+	struct amba_pl011_data *plat = dev_get_platdata(uap->port.dev);
 	struct dma_slave_config tx_conf = {
 		.dst_addr = uap->port.mapbase + UART01x_DR,
 		.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE,
@@ -677,6 +677,8 @@ static inline bool pl011_dma_tx_start(struct uart_amba_port *uap)
  * Locking: called with port lock held and IRQs disabled.
  */
 static void pl011_dma_flush_buffer(struct uart_port *port)
+__releases(&uap->port.lock)
+__acquires(&uap->port.lock)
 {
 	struct uart_amba_port *uap = (struct uart_amba_port *)port;
 
@@ -1198,6 +1200,8 @@ static void pl011_enable_ms(struct uart_port *port)
 }
 
 static void pl011_rx_chars(struct uart_amba_port *uap)
+__releases(&uap->port.lock)
+__acquires(&uap->port.lock)
 {
 	pl011_fifo_to_tty(uap);
 
@@ -1497,10 +1501,10 @@ static int pl011_hwinit(struct uart_port *port)
 	uap->im = readw(uap->port.membase + UART011_IMSC);
 	writew(UART011_RTIM | UART011_RXIM, uap->port.membase + UART011_IMSC);
 
-	if (uap->port.dev->platform_data) {
+	if (dev_get_platdata(uap->port.dev)) {
 		struct amba_pl011_data *plat;
 
-		plat = uap->port.dev->platform_data;
+		plat = dev_get_platdata(uap->port.dev);
 		if (plat->init)
 			plat->init();
 	}
@@ -1645,10 +1649,10 @@ static void pl011_shutdown(struct uart_port *port)
 	/* Optionally let pins go into sleep states */
 	pinctrl_pm_select_sleep_state(port->dev);
 
-	if (uap->port.dev->platform_data) {
+	if (dev_get_platdata(uap->port.dev)) {
 		struct amba_pl011_data *plat;
 
-		plat = uap->port.dev->platform_data;
+		plat = dev_get_platdata(uap->port.dev);
 		if (plat->exit)
 			plat->exit();
 	}
@@ -2002,10 +2006,10 @@ static int __init pl011_console_setup(struct console *co, char *options)
 	if (ret)
 		return ret;
 
-	if (uap->port.dev->platform_data) {
+	if (dev_get_platdata(uap->port.dev)) {
 		struct amba_pl011_data *plat;
 
-		plat = uap->port.dev->platform_data;
+		plat = dev_get_platdata(uap->port.dev);
 		if (plat->init)
 			plat->init();
 	}
diff --git a/drivers/tty/serial/apbuart.c b/drivers/tty/serial/apbuart.c
index 6331464d910..de11ab8ffd9 100644
--- a/drivers/tty/serial/apbuart.c
+++ b/drivers/tty/serial/apbuart.c
@@ -125,7 +125,9 @@ static void apbuart_rx_chars(struct uart_port *port)
 		status = UART_GET_STATUS(port);
 	}
 
+	spin_unlock(&port->lock);
 	tty_flip_buffer_push(&port->state->port);
+	spin_lock(&port->lock);
 }
 
 static void apbuart_tx_chars(struct uart_port *port)
diff --git a/drivers/tty/serial/ar933x_uart.c b/drivers/tty/serial/ar933x_uart.c
index 27f20c57abe..acd03af7cd5 100644
--- a/drivers/tty/serial/ar933x_uart.c
+++ b/drivers/tty/serial/ar933x_uart.c
@@ -17,6 +17,8 @@
 #include <linux/sysrq.h>
 #include <linux/delay.h>
 #include <linux/platform_device.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
 #include <linux/tty.h>
 #include <linux/tty_flip.h>
 #include <linux/serial_core.h>
@@ -24,11 +26,11 @@
 #include <linux/slab.h>
 #include <linux/io.h>
 #include <linux/irq.h>
+#include <linux/clk.h>
 
 #include <asm/div64.h>
 
 #include <asm/mach-ath79/ar933x_uart.h>
-#include <asm/mach-ath79/ar933x_uart_platform.h>
 
 #define DRIVER_NAME "ar933x-uart"
 
@@ -47,8 +49,14 @@ struct ar933x_uart_port {
 	unsigned int		ier;	/* shadow Interrupt Enable Register */
 	unsigned int		min_baud;
 	unsigned int		max_baud;
+	struct clk		*clk;
 };
 
+static inline bool ar933x_uart_console_enabled(void)
+{
+	return config_enabled(CONFIG_SERIAL_AR933X_CONSOLE);
+}
+
 static inline unsigned int ar933x_uart_read(struct ar933x_uart_port *up,
 					    int offset)
 {
@@ -322,7 +330,9 @@ static void ar933x_uart_rx_chars(struct ar933x_uart_port *up)
 			tty_insert_flip_char(port, ch, TTY_NORMAL);
 	} while (max_count-- > 0);
 
+	spin_unlock(&up->port.lock);
 	tty_flip_buffer_push(port);
+	spin_lock(&up->port.lock);
 }
 
 static void ar933x_uart_tx_chars(struct ar933x_uart_port *up)
@@ -497,8 +507,6 @@ static struct uart_ops ar933x_uart_ops = {
 	.verify_port	= ar933x_uart_verify_port,
 };
 
-#ifdef CONFIG_SERIAL_AR933X_CONSOLE
-
 static struct ar933x_uart_port *
 ar933x_console_ports[CONFIG_SERIAL_AR933X_NR_UARTS];
 
@@ -597,80 +605,88 @@ static struct console ar933x_uart_console = {
 
 static void ar933x_uart_add_console_port(struct ar933x_uart_port *up)
 {
+	if (!ar933x_uart_console_enabled())
+		return;
+
 	ar933x_console_ports[up->port.line] = up;
 }
 
-#define AR933X_SERIAL_CONSOLE	(&ar933x_uart_console)
-
-#else
-
-static inline void ar933x_uart_add_console_port(struct ar933x_uart_port *up) {}
-
-#define AR933X_SERIAL_CONSOLE	NULL
-
-#endif /* CONFIG_SERIAL_AR933X_CONSOLE */
-
 static struct uart_driver ar933x_uart_driver = {
 	.owner		= THIS_MODULE,
 	.driver_name	= DRIVER_NAME,
 	.dev_name	= "ttyATH",
 	.nr		= CONFIG_SERIAL_AR933X_NR_UARTS,
-	.cons		= AR933X_SERIAL_CONSOLE,
+	.cons		= NULL, /* filled in runtime */
 };
 
 static int ar933x_uart_probe(struct platform_device *pdev)
 {
-	struct ar933x_uart_platform_data *pdata;
 	struct ar933x_uart_port *up;
 	struct uart_port *port;
 	struct resource *mem_res;
 	struct resource *irq_res;
+	struct device_node *np;
 	unsigned int baud;
 	int id;
 	int ret;
 
-	pdata = pdev->dev.platform_data;
-	if (!pdata)
-		return -EINVAL;
-
-	id = pdev->id;
-	if (id == -1)
-		id = 0;
+	np = pdev->dev.of_node;
+	if (config_enabled(CONFIG_OF) && np) {
+		id = of_alias_get_id(np, "serial");
+		if (id < 0) {
+			dev_err(&pdev->dev, "unable to get alias id, err=%d\n",
+				id);
+			return id;
+		}
+	} else {
+		id = pdev->id;
+		if (id == -1)
+			id = 0;
+	}
 
 	if (id > CONFIG_SERIAL_AR933X_NR_UARTS)
 		return -EINVAL;
 
-	mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	if (!mem_res) {
-		dev_err(&pdev->dev, "no MEM resource\n");
-		return -EINVAL;
-	}
-
 	irq_res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
 	if (!irq_res) {
 		dev_err(&pdev->dev, "no IRQ resource\n");
 		return -EINVAL;
 	}
 
-	up = kzalloc(sizeof(struct ar933x_uart_port), GFP_KERNEL);
+	up = devm_kzalloc(&pdev->dev, sizeof(struct ar933x_uart_port),
+			  GFP_KERNEL);
 	if (!up)
 		return -ENOMEM;
 
+	up->clk = devm_clk_get(&pdev->dev, "uart");
+	if (IS_ERR(up->clk)) {
+		dev_err(&pdev->dev, "unable to get UART clock\n");
+		return PTR_ERR(up->clk);
+	}
+
 	port = &up->port;
-	port->mapbase = mem_res->start;
 
-	port->membase = ioremap(mem_res->start, AR933X_UART_REGS_SIZE);
-	if (!port->membase) {
-		ret = -ENOMEM;
-		goto err_free_up;
+	mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	port->membase = devm_ioremap_resource(&pdev->dev, mem_res);
+	if (IS_ERR(port->membase))
+		return PTR_ERR(port->membase);
+
+	ret = clk_prepare_enable(up->clk);
+	if (ret)
+		return ret;
+
+	port->uartclk = clk_get_rate(up->clk);
+	if (!port->uartclk) {
+		ret = -EINVAL;
+		goto err_disable_clk;
 	}
 
+	port->mapbase = mem_res->start;
 	port->line = id;
 	port->irq = irq_res->start;
 	port->dev = &pdev->dev;
 	port->type = PORT_AR933X;
 	port->iotype = UPIO_MEM32;
-	port->uartclk = pdata->uartclk;
 
 	port->regshift = 2;
 	port->fifosize = AR933X_UART_FIFO_SIZE;
@@ -686,15 +702,13 @@ static int ar933x_uart_probe(struct platform_device *pdev)
 
 	ret = uart_add_one_port(&ar933x_uart_driver, &up->port);
 	if (ret)
-		goto err_unmap;
+		goto err_disable_clk;
 
 	platform_set_drvdata(pdev, up);
 	return 0;
 
-err_unmap:
-	iounmap(up->port.membase);
-err_free_up:
-	kfree(up);
+err_disable_clk:
+	clk_disable_unprepare(up->clk);
 	return ret;
 }
 
@@ -703,23 +717,30 @@ static int ar933x_uart_remove(struct platform_device *pdev)
 	struct ar933x_uart_port *up;
 
 	up = platform_get_drvdata(pdev);
-	platform_set_drvdata(pdev, NULL);
 
 	if (up) {
 		uart_remove_one_port(&ar933x_uart_driver, &up->port);
-		iounmap(up->port.membase);
-		kfree(up);
+		clk_disable_unprepare(up->clk);
 	}
 
 	return 0;
 }
 
+#ifdef CONFIG_OF
+static const struct of_device_id ar933x_uart_of_ids[] = {
+	{ .compatible = "qca,ar9330-uart" },
+	{},
+};
+MODULE_DEVICE_TABLE(of, ar933x_uart_of_ids);
+#endif
+
 static struct platform_driver ar933x_uart_platform_driver = {
 	.probe		= ar933x_uart_probe,
 	.remove		= ar933x_uart_remove,
 	.driver		= {
 		.name		= DRIVER_NAME,
 		.owner		= THIS_MODULE,
+		.of_match_table = of_match_ptr(ar933x_uart_of_ids),
 	},
 };
 
@@ -727,7 +748,9 @@ static int __init ar933x_uart_init(void)
 {
 	int ret;
 
-	ar933x_uart_driver.nr = CONFIG_SERIAL_AR933X_NR_UARTS;
+	if (ar933x_uart_console_enabled())
+		ar933x_uart_driver.cons = &ar933x_uart_console;
+
 	ret = uart_register_driver(&ar933x_uart_driver);
 	if (ret)
 		goto err_out;
diff --git a/drivers/tty/serial/arc_uart.c b/drivers/tty/serial/arc_uart.c
index 22f280aa4f2..569872f4c9b 100644
--- a/drivers/tty/serial/arc_uart.c
+++ b/drivers/tty/serial/arc_uart.c
@@ -209,9 +209,9 @@ static void arc_serial_start_tx(struct uart_port *port)
 	arc_serial_tx_chars(uart);
 }
 
-static void arc_serial_rx_chars(struct arc_uart_port *uart)
+static void arc_serial_rx_chars(struct arc_uart_port *uart, unsigned int status)
 {
-	unsigned int status, ch, flg = 0;
+	unsigned int ch, flg = 0;
 
 	/*
 	 * UART has 4 deep RX-FIFO. Driver's recongnition of this fact
@@ -222,11 +222,11 @@ static void arc_serial_rx_chars(struct arc_uart_port *uart)
 	 * before RX-EMPTY=0, implies some sort of buffering going on in the
 	 * controller, which is indeed the Rx-FIFO.
 	 */
-	while (!((status = UART_GET_STATUS(uart)) & RXEMPTY)) {
-
-		ch = UART_GET_DATA(uart);
-		uart->port.icount.rx++;
-
+	do {
+		/*
+		 * This could be an Rx Intr for err (no data),
+		 * so check err and clear that Intr first
+		 */
 		if (unlikely(status & (RXOERR | RXFERR))) {
 			if (status & RXOERR) {
 				uart->port.icount.overrun++;
@@ -242,14 +242,19 @@ static void arc_serial_rx_chars(struct arc_uart_port *uart)
 		} else
 			flg = TTY_NORMAL;
 
-		if (unlikely(uart_handle_sysrq_char(&uart->port, ch)))
-			goto done;
+		if (status & RXEMPTY)
+			continue;
 
-		uart_insert_char(&uart->port, status, RXOERR, ch, flg);
+		ch = UART_GET_DATA(uart);
+		uart->port.icount.rx++;
+
+		if (!(uart_handle_sysrq_char(&uart->port, ch)))
+			uart_insert_char(&uart->port, status, RXOERR, ch, flg);
 
-done:
+		spin_unlock(&uart->port.lock);
 		tty_flip_buffer_push(&uart->port.state->port);
-	}
+		spin_lock(&uart->port.lock);
+	} while (!((status = UART_GET_STATUS(uart)) & RXEMPTY));
 }
 
 /*
@@ -292,11 +297,11 @@ static irqreturn_t arc_serial_isr(int irq, void *dev_id)
 	 * notifications from the UART Controller.
 	 * To demultiplex between the two, we check the relevant bits
 	 */
-	if ((status & RXIENB) && !(status & RXEMPTY)) {
+	if (status & RXIENB) {
 
 		/* already in ISR, no need of xx_irqsave */
 		spin_lock(&uart->port.lock);
-		arc_serial_rx_chars(uart);
+		arc_serial_rx_chars(uart, status);
 		spin_unlock(&uart->port.lock);
 	}
 
@@ -528,7 +533,7 @@ arc_uart_init_one(struct platform_device *pdev, int dev_id)
 	unsigned long *plat_data;
 	struct arc_uart_port *uart = &arc_uart_ports[dev_id];
 
-	plat_data = ((unsigned long *)(pdev->dev.platform_data));
+	plat_data = (unsigned long *)dev_get_platdata(&pdev->dev);
 	if (!plat_data)
 		return -ENODEV;
 
diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c
index 691265faebb..d067285a2d2 100644
--- a/drivers/tty/serial/atmel_serial.c
+++ b/drivers/tty/serial/atmel_serial.c
@@ -39,8 +39,8 @@
 #include <linux/atmel_pdc.h>
 #include <linux/atmel_serial.h>
 #include <linux/uaccess.h>
-#include <linux/pinctrl/consumer.h>
 #include <linux/platform_data/atmel.h>
+#include <linux/timer.h>
 
 #include <asm/io.h>
 #include <asm/ioctls.h>
@@ -98,6 +98,7 @@ static void atmel_stop_rx(struct uart_port *port);
 #define UART_PUT_BRGR(port,v)	__raw_writel(v, (port)->membase + ATMEL_US_BRGR)
 #define UART_PUT_RTOR(port,v)	__raw_writel(v, (port)->membase + ATMEL_US_RTOR)
 #define UART_PUT_TTGR(port, v)	__raw_writel(v, (port)->membase + ATMEL_US_TTGR)
+#define UART_GET_IP_NAME(port)	__raw_readl((port)->membase + ATMEL_US_NAME)
 
  /* PDC registers */
 #define UART_PUT_PTCR(port,v)	__raw_writel(v, (port)->membase + ATMEL_PDC_PTCR)
@@ -140,13 +141,25 @@ struct atmel_uart_port {
 	u32			backup_imr;	/* IMR saved during suspend */
 	int			break_active;	/* break being received */
 
-	short			use_dma_rx;	/* enable PDC receiver */
+	bool			use_dma_rx;	/* enable DMA receiver */
+	bool			use_pdc_rx;	/* enable PDC receiver */
 	short			pdc_rx_idx;	/* current PDC RX buffer */
 	struct atmel_dma_buffer	pdc_rx[2];	/* PDC receier */
 
-	short			use_dma_tx;	/* enable PDC transmitter */
+	bool			use_dma_tx;     /* enable DMA transmitter */
+	bool			use_pdc_tx;	/* enable PDC transmitter */
 	struct atmel_dma_buffer	pdc_tx;		/* PDC transmitter */
 
+	spinlock_t			lock_tx;	/* port lock */
+	spinlock_t			lock_rx;	/* port lock */
+	struct dma_chan			*chan_tx;
+	struct dma_chan			*chan_rx;
+	struct dma_async_tx_descriptor	*desc_tx;
+	struct dma_async_tx_descriptor	*desc_rx;
+	dma_cookie_t			cookie_tx;
+	dma_cookie_t			cookie_rx;
+	struct scatterlist		sg_tx;
+	struct scatterlist		sg_rx;
 	struct tasklet_struct	tasklet;
 	unsigned int		irq_status;
 	unsigned int		irq_status_prev;
@@ -155,6 +168,14 @@ struct atmel_uart_port {
 
 	struct serial_rs485	rs485;		/* rs485 settings */
 	unsigned int		tx_done_mask;
+	bool			is_usart;	/* usart or uart */
+	struct timer_list	uart_timer;	/* uart timer */
+	int (*prepare_rx)(struct uart_port *port);
+	int (*prepare_tx)(struct uart_port *port);
+	void (*schedule_rx)(struct uart_port *port);
+	void (*schedule_tx)(struct uart_port *port);
+	void (*release_rx)(struct uart_port *port);
+	void (*release_tx)(struct uart_port *port);
 };
 
 static struct atmel_uart_port atmel_ports[ATMEL_MAX_UART];
@@ -181,31 +202,45 @@ to_atmel_uart_port(struct uart_port *uart)
 }
 
 #ifdef CONFIG_SERIAL_ATMEL_PDC
-static bool atmel_use_dma_rx(struct uart_port *port)
+static bool atmel_use_pdc_rx(struct uart_port *port)
 {
 	struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
 
-	return atmel_port->use_dma_rx;
+	return atmel_port->use_pdc_rx;
 }
 
-static bool atmel_use_dma_tx(struct uart_port *port)
+static bool atmel_use_pdc_tx(struct uart_port *port)
 {
 	struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
 
-	return atmel_port->use_dma_tx;
+	return atmel_port->use_pdc_tx;
 }
 #else
-static bool atmel_use_dma_rx(struct uart_port *port)
+static bool atmel_use_pdc_rx(struct uart_port *port)
 {
 	return false;
 }
 
-static bool atmel_use_dma_tx(struct uart_port *port)
+static bool atmel_use_pdc_tx(struct uart_port *port)
 {
 	return false;
 }
 #endif
 
+static bool atmel_use_dma_tx(struct uart_port *port)
+{
+	struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+
+	return atmel_port->use_dma_tx;
+}
+
+static bool atmel_use_dma_rx(struct uart_port *port)
+{
+	struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+
+	return atmel_port->use_dma_rx;
+}
+
 /* Enable or disable the rs485 support */
 void atmel_config_rs485(struct uart_port *port, struct serial_rs485 *rs485conf)
 {
@@ -233,7 +268,7 @@ void atmel_config_rs485(struct uart_port *port, struct serial_rs485 *rs485conf)
 		mode |= ATMEL_US_USMODE_RS485;
 	} else {
 		dev_dbg(port->dev, "Setting UART to RS232\n");
-		if (atmel_use_dma_tx(port))
+		if (atmel_use_pdc_tx(port))
 			atmel_port->tx_done_mask = ATMEL_US_ENDTX |
 				ATMEL_US_TXBUFE;
 		else
@@ -345,7 +380,7 @@ static void atmel_stop_tx(struct uart_port *port)
 {
 	struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
 
-	if (atmel_use_dma_tx(port)) {
+	if (atmel_use_pdc_tx(port)) {
 		/* disable PDC transmit */
 		UART_PUT_PTCR(port, ATMEL_PDC_TXTDIS);
 	}
@@ -364,7 +399,7 @@ static void atmel_start_tx(struct uart_port *port)
 {
 	struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
 
-	if (atmel_use_dma_tx(port)) {
+	if (atmel_use_pdc_tx(port)) {
 		if (UART_GET_PTSR(port) & ATMEL_PDC_TXTEN)
 			/* The transmitter is already running.  Yes, we
 			   really need this.*/
@@ -390,7 +425,7 @@ static void atmel_start_rx(struct uart_port *port)
 
 	UART_PUT_CR(port, ATMEL_US_RXEN);
 
-	if (atmel_use_dma_rx(port)) {
+	if (atmel_use_pdc_rx(port)) {
 		/* enable PDC controller */
 		UART_PUT_IER(port, ATMEL_US_ENDRX | ATMEL_US_TIMEOUT |
 			port->read_status_mask);
@@ -407,7 +442,7 @@ static void atmel_stop_rx(struct uart_port *port)
 {
 	UART_PUT_CR(port, ATMEL_US_RXDIS);
 
-	if (atmel_use_dma_rx(port)) {
+	if (atmel_use_pdc_rx(port)) {
 		/* disable PDC receive */
 		UART_PUT_PTCR(port, ATMEL_PDC_RXTDIS);
 		UART_PUT_IDR(port, ATMEL_US_ENDRX | ATMEL_US_TIMEOUT |
@@ -564,6 +599,372 @@ static void atmel_tx_chars(struct uart_port *port)
 		UART_PUT_IER(port, atmel_port->tx_done_mask);
 }
 
+static void atmel_complete_tx_dma(void *arg)
+{
+	struct atmel_uart_port *atmel_port = arg;
+	struct uart_port *port = &atmel_port->uart;
+	struct circ_buf *xmit = &port->state->xmit;
+	struct dma_chan *chan = atmel_port->chan_tx;
+	unsigned long flags;
+
+	spin_lock_irqsave(&port->lock, flags);
+
+	if (chan)
+		dmaengine_terminate_all(chan);
+	xmit->tail += sg_dma_len(&atmel_port->sg_tx);
+	xmit->tail &= UART_XMIT_SIZE - 1;
+
+	port->icount.tx += sg_dma_len(&atmel_port->sg_tx);
+
+	spin_lock_irq(&atmel_port->lock_tx);
+	async_tx_ack(atmel_port->desc_tx);
+	atmel_port->cookie_tx = -EINVAL;
+	atmel_port->desc_tx = NULL;
+	spin_unlock_irq(&atmel_port->lock_tx);
+
+	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+		uart_write_wakeup(port);
+
+	/* Do we really need this? */
+	if (!uart_circ_empty(xmit))
+		tasklet_schedule(&atmel_port->tasklet);
+
+	spin_unlock_irqrestore(&port->lock, flags);
+}
+
+static void atmel_release_tx_dma(struct uart_port *port)
+{
+	struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+	struct dma_chan *chan = atmel_port->chan_tx;
+
+	if (chan) {
+		dmaengine_terminate_all(chan);
+		dma_release_channel(chan);
+		dma_unmap_sg(port->dev, &atmel_port->sg_tx, 1,
+				DMA_MEM_TO_DEV);
+	}
+
+	atmel_port->desc_tx = NULL;
+	atmel_port->chan_tx = NULL;
+	atmel_port->cookie_tx = -EINVAL;
+}
+
+/*
+ * Called from tasklet with TXRDY interrupt is disabled.
+ */
+static void atmel_tx_dma(struct uart_port *port)
+{
+	struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+	struct circ_buf *xmit = &port->state->xmit;
+	struct dma_chan *chan = atmel_port->chan_tx;
+	struct dma_async_tx_descriptor *desc;
+	struct scatterlist *sg = &atmel_port->sg_tx;
+
+	/* Make sure we have an idle channel */
+	if (atmel_port->desc_tx != NULL)
+		return;
+
+	if (!uart_circ_empty(xmit) && !uart_tx_stopped(port)) {
+		/*
+		 * DMA is idle now.
+		 * Port xmit buffer is already mapped,
+		 * and it is one page... Just adjust
+		 * offsets and lengths. Since it is a circular buffer,
+		 * we have to transmit till the end, and then the rest.
+		 * Take the port lock to get a
+		 * consistent xmit buffer state.
+		 */
+		sg->offset = xmit->tail & (UART_XMIT_SIZE - 1);
+		sg_dma_address(sg) = (sg_dma_address(sg) &
+					~(UART_XMIT_SIZE - 1))
+					+ sg->offset;
+		sg_dma_len(sg) = CIRC_CNT_TO_END(xmit->head,
+						xmit->tail,
+						UART_XMIT_SIZE);
+		BUG_ON(!sg_dma_len(sg));
+
+		desc = dmaengine_prep_slave_sg(chan,
+						sg,
+						1,
+						DMA_MEM_TO_DEV,
+						DMA_PREP_INTERRUPT |
+						DMA_CTRL_ACK);
+		if (!desc) {
+			dev_err(port->dev, "Failed to send via dma!\n");
+			return;
+		}
+
+		dma_sync_sg_for_device(port->dev, sg, 1, DMA_MEM_TO_DEV);
+
+		atmel_port->desc_tx = desc;
+		desc->callback = atmel_complete_tx_dma;
+		desc->callback_param = atmel_port;
+		atmel_port->cookie_tx = dmaengine_submit(desc);
+
+	} else {
+		if (atmel_port->rs485.flags & SER_RS485_ENABLED) {
+			/* DMA done, stop TX, start RX for RS485 */
+			atmel_start_rx(port);
+		}
+	}
+
+	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+		uart_write_wakeup(port);
+}
+
+static int atmel_prepare_tx_dma(struct uart_port *port)
+{
+	struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+	dma_cap_mask_t		mask;
+	struct dma_slave_config config;
+	int ret, nent;
+
+	dma_cap_zero(mask);
+	dma_cap_set(DMA_SLAVE, mask);
+
+	atmel_port->chan_tx = dma_request_slave_channel(port->dev, "tx");
+	if (atmel_port->chan_tx == NULL)
+		goto chan_err;
+	dev_info(port->dev, "using %s for tx DMA transfers\n",
+		dma_chan_name(atmel_port->chan_tx));
+
+	spin_lock_init(&atmel_port->lock_tx);
+	sg_init_table(&atmel_port->sg_tx, 1);
+	/* UART circular tx buffer is an aligned page. */
+	BUG_ON((int)port->state->xmit.buf & ~PAGE_MASK);
+	sg_set_page(&atmel_port->sg_tx,
+			virt_to_page(port->state->xmit.buf),
+			UART_XMIT_SIZE,
+			(int)port->state->xmit.buf & ~PAGE_MASK);
+	nent = dma_map_sg(port->dev,
+				&atmel_port->sg_tx,
+				1,
+				DMA_MEM_TO_DEV);
+
+	if (!nent) {
+		dev_dbg(port->dev, "need to release resource of dma\n");
+		goto chan_err;
+	} else {
+		dev_dbg(port->dev, "%s: mapped %d@%p to %x\n", __func__,
+			sg_dma_len(&atmel_port->sg_tx),
+			port->state->xmit.buf,
+			sg_dma_address(&atmel_port->sg_tx));
+	}
+
+	/* Configure the slave DMA */
+	memset(&config, 0, sizeof(config));
+	config.direction = DMA_MEM_TO_DEV;
+	config.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
+	config.dst_addr = port->mapbase + ATMEL_US_THR;
+
+	ret = dmaengine_device_control(atmel_port->chan_tx,
+					DMA_SLAVE_CONFIG,
+					(unsigned long)&config);
+	if (ret) {
+		dev_err(port->dev, "DMA tx slave configuration failed\n");
+		goto chan_err;
+	}
+
+	return 0;
+
+chan_err:
+	dev_err(port->dev, "TX channel not available, switch to pio\n");
+	atmel_port->use_dma_tx = 0;
+	if (atmel_port->chan_tx)
+		atmel_release_tx_dma(port);
+	return -EINVAL;
+}
+
+static void atmel_flip_buffer_rx_dma(struct uart_port *port,
+					char *buf, size_t count)
+{
+	struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+	struct tty_port *tport = &port->state->port;
+
+	dma_sync_sg_for_cpu(port->dev,
+				&atmel_port->sg_rx,
+				1,
+				DMA_DEV_TO_MEM);
+
+	tty_insert_flip_string(tport, buf, count);
+
+	dma_sync_sg_for_device(port->dev,
+				&atmel_port->sg_rx,
+				1,
+				DMA_DEV_TO_MEM);
+	/*
+	 * Drop the lock here since it might end up calling
+	 * uart_start(), which takes the lock.
+	 */
+	spin_unlock(&port->lock);
+	tty_flip_buffer_push(tport);
+	spin_lock(&port->lock);
+}
+
+static void atmel_complete_rx_dma(void *arg)
+{
+	struct uart_port *port = arg;
+	struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+
+	tasklet_schedule(&atmel_port->tasklet);
+}
+
+static void atmel_release_rx_dma(struct uart_port *port)
+{
+	struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+	struct dma_chan *chan = atmel_port->chan_rx;
+
+	if (chan) {
+		dmaengine_terminate_all(chan);
+		dma_release_channel(chan);
+		dma_unmap_sg(port->dev, &atmel_port->sg_rx, 1,
+				DMA_DEV_TO_MEM);
+	}
+
+	atmel_port->desc_rx = NULL;
+	atmel_port->chan_rx = NULL;
+	atmel_port->cookie_rx = -EINVAL;
+
+	if (!atmel_port->is_usart)
+		del_timer_sync(&atmel_port->uart_timer);
+}
+
+static void atmel_rx_from_dma(struct uart_port *port)
+{
+	struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+	struct circ_buf *ring = &atmel_port->rx_ring;
+	struct dma_chan *chan = atmel_port->chan_rx;
+	struct dma_tx_state state;
+	enum dma_status dmastat;
+	size_t pending, count;
+
+
+	/* Reset the UART timeout early so that we don't miss one */
+	UART_PUT_CR(port, ATMEL_US_STTTO);
+	dmastat = dmaengine_tx_status(chan,
+				atmel_port->cookie_rx,
+				&state);
+	/* Restart a new tasklet if DMA status is error */
+	if (dmastat == DMA_ERROR) {
+		dev_dbg(port->dev, "Get residue error, restart tasklet\n");
+		UART_PUT_IER(port, ATMEL_US_TIMEOUT);
+		tasklet_schedule(&atmel_port->tasklet);
+		return;
+	}
+	/* current transfer size should no larger than dma buffer */
+	pending = sg_dma_len(&atmel_port->sg_rx) - state.residue;
+	BUG_ON(pending > sg_dma_len(&atmel_port->sg_rx));
+
+	/*
+	 * This will take the chars we have so far,
+	 * ring->head will record the transfer size, only new bytes come
+	 * will insert into the framework.
+	 */
+	if (pending > ring->head) {
+		count = pending - ring->head;
+
+		atmel_flip_buffer_rx_dma(port, ring->buf + ring->head, count);
+
+		ring->head += count;
+		if (ring->head == sg_dma_len(&atmel_port->sg_rx))
+			ring->head = 0;
+
+		port->icount.rx += count;
+	}
+
+	UART_PUT_IER(port, ATMEL_US_TIMEOUT);
+}
+
+static int atmel_prepare_rx_dma(struct uart_port *port)
+{
+	struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+	struct dma_async_tx_descriptor *desc;
+	dma_cap_mask_t		mask;
+	struct dma_slave_config config;
+	struct circ_buf		*ring;
+	int ret, nent;
+
+	ring = &atmel_port->rx_ring;
+
+	dma_cap_zero(mask);
+	dma_cap_set(DMA_CYCLIC, mask);
+
+	atmel_port->chan_rx = dma_request_slave_channel(port->dev, "rx");
+	if (atmel_port->chan_rx == NULL)
+		goto chan_err;
+	dev_info(port->dev, "using %s for rx DMA transfers\n",
+		dma_chan_name(atmel_port->chan_rx));
+
+	spin_lock_init(&atmel_port->lock_rx);
+	sg_init_table(&atmel_port->sg_rx, 1);
+	/* UART circular rx buffer is an aligned page. */
+	BUG_ON((int)port->state->xmit.buf & ~PAGE_MASK);
+	sg_set_page(&atmel_port->sg_rx,
+			virt_to_page(ring->buf),
+			ATMEL_SERIAL_RINGSIZE,
+			(int)ring->buf & ~PAGE_MASK);
+			nent = dma_map_sg(port->dev,
+					&atmel_port->sg_rx,
+					1,
+					DMA_DEV_TO_MEM);
+
+	if (!nent) {
+		dev_dbg(port->dev, "need to release resource of dma\n");
+		goto chan_err;
+	} else {
+		dev_dbg(port->dev, "%s: mapped %d@%p to %x\n", __func__,
+			sg_dma_len(&atmel_port->sg_rx),
+			ring->buf,
+			sg_dma_address(&atmel_port->sg_rx));
+	}
+
+	/* Configure the slave DMA */
+	memset(&config, 0, sizeof(config));
+	config.direction = DMA_DEV_TO_MEM;
+	config.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
+	config.src_addr = port->mapbase + ATMEL_US_RHR;
+
+	ret = dmaengine_device_control(atmel_port->chan_rx,
+					DMA_SLAVE_CONFIG,
+					(unsigned long)&config);
+	if (ret) {
+		dev_err(port->dev, "DMA rx slave configuration failed\n");
+		goto chan_err;
+	}
+	/*
+	 * Prepare a cyclic dma transfer, assign 2 descriptors,
+	 * each one is half ring buffer size
+	 */
+	desc = dmaengine_prep_dma_cyclic(atmel_port->chan_rx,
+				sg_dma_address(&atmel_port->sg_rx),
+				sg_dma_len(&atmel_port->sg_rx),
+				sg_dma_len(&atmel_port->sg_rx)/2,
+				DMA_DEV_TO_MEM,
+				DMA_PREP_INTERRUPT);
+	desc->callback = atmel_complete_rx_dma;
+	desc->callback_param = port;
+	atmel_port->desc_rx = desc;
+	atmel_port->cookie_rx = dmaengine_submit(desc);
+
+	return 0;
+
+chan_err:
+	dev_err(port->dev, "RX channel not available, switch to pio\n");
+	atmel_port->use_dma_rx = 0;
+	if (atmel_port->chan_rx)
+		atmel_release_rx_dma(port);
+	return -EINVAL;
+}
+
+static void atmel_uart_timer_callback(unsigned long data)
+{
+	struct uart_port *port = (void *)data;
+	struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+
+	tasklet_schedule(&atmel_port->tasklet);
+	mod_timer(&atmel_port->uart_timer, jiffies + uart_poll_timeout(port));
+}
+
 /*
  * receive interrupt handler.
  */
@@ -572,7 +973,7 @@ atmel_handle_receive(struct uart_port *port, unsigned int pending)
 {
 	struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
 
-	if (atmel_use_dma_rx(port)) {
+	if (atmel_use_pdc_rx(port)) {
 		/*
 		 * PDC receive. Just schedule the tasklet and let it
 		 * figure out the details.
@@ -591,6 +992,13 @@ atmel_handle_receive(struct uart_port *port, unsigned int pending)
 			atmel_pdc_rxerr(port, pending);
 	}
 
+	if (atmel_use_dma_rx(port)) {
+		if (pending & ATMEL_US_TIMEOUT) {
+			UART_PUT_IDR(port, ATMEL_US_TIMEOUT);
+			tasklet_schedule(&atmel_port->tasklet);
+		}
+	}
+
 	/* Interrupt receive */
 	if (pending & ATMEL_US_RXRDY)
 		atmel_rx_chars(port);
@@ -658,10 +1066,21 @@ static irqreturn_t atmel_interrupt(int irq, void *dev_id)
 	return pass_counter ? IRQ_HANDLED : IRQ_NONE;
 }
 
+static void atmel_release_tx_pdc(struct uart_port *port)
+{
+	struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+	struct atmel_dma_buffer *pdc = &atmel_port->pdc_tx;
+
+	dma_unmap_single(port->dev,
+			 pdc->dma_addr,
+			 pdc->dma_size,
+			 DMA_TO_DEVICE);
+}
+
 /*
  * Called from tasklet with ENDTX and TXBUFE interrupts disabled.
  */
-static void atmel_tx_dma(struct uart_port *port)
+static void atmel_tx_pdc(struct uart_port *port)
 {
 	struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
 	struct circ_buf *xmit = &port->state->xmit;
@@ -710,6 +1129,23 @@ static void atmel_tx_dma(struct uart_port *port)
 		uart_write_wakeup(port);
 }
 
+static int atmel_prepare_tx_pdc(struct uart_port *port)
+{
+	struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+	struct atmel_dma_buffer *pdc = &atmel_port->pdc_tx;
+	struct circ_buf *xmit = &port->state->xmit;
+
+	pdc->buf = xmit->buf;
+	pdc->dma_addr = dma_map_single(port->dev,
+					pdc->buf,
+					UART_XMIT_SIZE,
+					DMA_TO_DEVICE);
+	pdc->dma_size = UART_XMIT_SIZE;
+	pdc->ofs = 0;
+
+	return 0;
+}
+
 static void atmel_rx_from_ring(struct uart_port *port)
 {
 	struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
@@ -778,7 +1214,26 @@ static void atmel_rx_from_ring(struct uart_port *port)
 	spin_lock(&port->lock);
 }
 
-static void atmel_rx_from_dma(struct uart_port *port)
+static void atmel_release_rx_pdc(struct uart_port *port)
+{
+	struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+	int i;
+
+	for (i = 0; i < 2; i++) {
+		struct atmel_dma_buffer *pdc = &atmel_port->pdc_rx[i];
+
+		dma_unmap_single(port->dev,
+				 pdc->dma_addr,
+				 pdc->dma_size,
+				 DMA_FROM_DEVICE);
+		kfree(pdc->buf);
+	}
+
+	if (!atmel_port->is_usart)
+		del_timer_sync(&atmel_port->uart_timer);
+}
+
+static void atmel_rx_from_pdc(struct uart_port *port)
 {
 	struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
 	struct tty_port *tport = &port->state->port;
@@ -855,6 +1310,45 @@ static void atmel_rx_from_dma(struct uart_port *port)
 	UART_PUT_IER(port, ATMEL_US_ENDRX | ATMEL_US_TIMEOUT);
 }
 
+static int atmel_prepare_rx_pdc(struct uart_port *port)
+{
+	struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+	int i;
+
+	for (i = 0; i < 2; i++) {
+		struct atmel_dma_buffer *pdc = &atmel_port->pdc_rx[i];
+
+		pdc->buf = kmalloc(PDC_BUFFER_SIZE, GFP_KERNEL);
+		if (pdc->buf == NULL) {
+			if (i != 0) {
+				dma_unmap_single(port->dev,
+					atmel_port->pdc_rx[0].dma_addr,
+					PDC_BUFFER_SIZE,
+					DMA_FROM_DEVICE);
+				kfree(atmel_port->pdc_rx[0].buf);
+			}
+			atmel_port->use_pdc_rx = 0;
+			return -ENOMEM;
+		}
+		pdc->dma_addr = dma_map_single(port->dev,
+						pdc->buf,
+						PDC_BUFFER_SIZE,
+						DMA_FROM_DEVICE);
+		pdc->dma_size = PDC_BUFFER_SIZE;
+		pdc->ofs = 0;
+	}
+
+	atmel_port->pdc_rx_idx = 0;
+
+	UART_PUT_RPR(port, atmel_port->pdc_rx[0].dma_addr);
+	UART_PUT_RCR(port, PDC_BUFFER_SIZE);
+
+	UART_PUT_RNPR(port, atmel_port->pdc_rx[1].dma_addr);
+	UART_PUT_RNCR(port, PDC_BUFFER_SIZE);
+
+	return 0;
+}
+
 /*
  * tasklet handling tty stuff outside the interrupt handler.
  */
@@ -868,10 +1362,7 @@ static void atmel_tasklet_func(unsigned long data)
 	/* The interrupt handler does not take the lock */
 	spin_lock(&port->lock);
 
-	if (atmel_use_dma_tx(port))
-		atmel_tx_dma(port);
-	else
-		atmel_tx_chars(port);
+	atmel_port->schedule_tx(port);
 
 	status = atmel_port->irq_status;
 	status_change = status ^ atmel_port->irq_status_prev;
@@ -893,19 +1384,152 @@ static void atmel_tasklet_func(unsigned long data)
 		atmel_port->irq_status_prev = status;
 	}
 
-	if (atmel_use_dma_rx(port))
-		atmel_rx_from_dma(port);
-	else
-		atmel_rx_from_ring(port);
+	atmel_port->schedule_rx(port);
 
 	spin_unlock(&port->lock);
 }
 
+static int atmel_init_property(struct atmel_uart_port *atmel_port,
+				struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	struct atmel_uart_data *pdata = dev_get_platdata(&pdev->dev);
+
+	if (np) {
+		/* DMA/PDC usage specification */
+		if (of_get_property(np, "atmel,use-dma-rx", NULL)) {
+			if (of_get_property(np, "dmas", NULL)) {
+				atmel_port->use_dma_rx  = true;
+				atmel_port->use_pdc_rx  = false;
+			} else {
+				atmel_port->use_dma_rx  = false;
+				atmel_port->use_pdc_rx  = true;
+			}
+		} else {
+			atmel_port->use_dma_rx  = false;
+			atmel_port->use_pdc_rx  = false;
+		}
+
+		if (of_get_property(np, "atmel,use-dma-tx", NULL)) {
+			if (of_get_property(np, "dmas", NULL)) {
+				atmel_port->use_dma_tx  = true;
+				atmel_port->use_pdc_tx  = false;
+			} else {
+				atmel_port->use_dma_tx  = false;
+				atmel_port->use_pdc_tx  = true;
+			}
+		} else {
+			atmel_port->use_dma_tx  = false;
+			atmel_port->use_pdc_tx  = false;
+		}
+
+	} else {
+		atmel_port->use_pdc_rx  = pdata->use_dma_rx;
+		atmel_port->use_pdc_tx  = pdata->use_dma_tx;
+		atmel_port->use_dma_rx  = false;
+		atmel_port->use_dma_tx  = false;
+	}
+
+	return 0;
+}
+
+static void atmel_init_rs485(struct atmel_uart_port *atmel_port,
+				struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	struct atmel_uart_data *pdata = dev_get_platdata(&pdev->dev);
+
+	if (np) {
+		u32 rs485_delay[2];
+		/* rs485 properties */
+		if (of_property_read_u32_array(np, "rs485-rts-delay",
+					rs485_delay, 2) == 0) {
+			struct serial_rs485 *rs485conf = &atmel_port->rs485;
+
+			rs485conf->delay_rts_before_send = rs485_delay[0];
+			rs485conf->delay_rts_after_send = rs485_delay[1];
+			rs485conf->flags = 0;
+
+		if (of_get_property(np, "rs485-rx-during-tx", NULL))
+			rs485conf->flags |= SER_RS485_RX_DURING_TX;
+
+		if (of_get_property(np, "linux,rs485-enabled-at-boot-time",
+								NULL))
+			rs485conf->flags |= SER_RS485_ENABLED;
+		}
+	} else {
+		atmel_port->rs485       = pdata->rs485;
+	}
+
+}
+
+static void atmel_set_ops(struct uart_port *port)
+{
+	struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+
+	if (atmel_use_dma_rx(port)) {
+		atmel_port->prepare_rx = &atmel_prepare_rx_dma;
+		atmel_port->schedule_rx = &atmel_rx_from_dma;
+		atmel_port->release_rx = &atmel_release_rx_dma;
+	} else if (atmel_use_pdc_rx(port)) {
+		atmel_port->prepare_rx = &atmel_prepare_rx_pdc;
+		atmel_port->schedule_rx = &atmel_rx_from_pdc;
+		atmel_port->release_rx = &atmel_release_rx_pdc;
+	} else {
+		atmel_port->prepare_rx = NULL;
+		atmel_port->schedule_rx = &atmel_rx_from_ring;
+		atmel_port->release_rx = NULL;
+	}
+
+	if (atmel_use_dma_tx(port)) {
+		atmel_port->prepare_tx = &atmel_prepare_tx_dma;
+		atmel_port->schedule_tx = &atmel_tx_dma;
+		atmel_port->release_tx = &atmel_release_tx_dma;
+	} else if (atmel_use_pdc_tx(port)) {
+		atmel_port->prepare_tx = &atmel_prepare_tx_pdc;
+		atmel_port->schedule_tx = &atmel_tx_pdc;
+		atmel_port->release_tx = &atmel_release_tx_pdc;
+	} else {
+		atmel_port->prepare_tx = NULL;
+		atmel_port->schedule_tx = &atmel_tx_chars;
+		atmel_port->release_tx = NULL;
+	}
+}
+
+/*
+ * Get ip name usart or uart
+ */
+static int atmel_get_ip_name(struct uart_port *port)
+{
+	struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
+	int name = UART_GET_IP_NAME(port);
+	int usart, uart;
+	/* usart and uart ascii */
+	usart = 0x55534152;
+	uart = 0x44424755;
+
+	atmel_port->is_usart = false;
+
+	if (name == usart) {
+		dev_dbg(port->dev, "This is usart\n");
+		atmel_port->is_usart = true;
+	} else if (name == uart) {
+		dev_dbg(port->dev, "This is uart\n");
+		atmel_port->is_usart = false;
+	} else {
+		dev_err(port->dev, "Not supported ip name, set to uart\n");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
 /*
  * Perform initialization and enable port for reception
  */
 static int atmel_startup(struct uart_port *port)
 {
+	struct platform_device *pdev = to_platform_device(port->dev);
 	struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
 	struct tty_struct *tty = port->state->port.tty;
 	int retval;
@@ -930,53 +1554,19 @@ static int atmel_startup(struct uart_port *port)
 	/*
 	 * Initialize DMA (if necessary)
 	 */
-	if (atmel_use_dma_rx(port)) {
-		int i;
-
-		for (i = 0; i < 2; i++) {
-			struct atmel_dma_buffer *pdc = &atmel_port->pdc_rx[i];
-
-			pdc->buf = kmalloc(PDC_BUFFER_SIZE, GFP_KERNEL);
-			if (pdc->buf == NULL) {
-				if (i != 0) {
-					dma_unmap_single(port->dev,
-						atmel_port->pdc_rx[0].dma_addr,
-						PDC_BUFFER_SIZE,
-						DMA_FROM_DEVICE);
-					kfree(atmel_port->pdc_rx[0].buf);
-				}
-				free_irq(port->irq, port);
-				return -ENOMEM;
-			}
-			pdc->dma_addr = dma_map_single(port->dev,
-						       pdc->buf,
-						       PDC_BUFFER_SIZE,
-						       DMA_FROM_DEVICE);
-			pdc->dma_size = PDC_BUFFER_SIZE;
-			pdc->ofs = 0;
-		}
+	atmel_init_property(atmel_port, pdev);
 
-		atmel_port->pdc_rx_idx = 0;
-
-		UART_PUT_RPR(port, atmel_port->pdc_rx[0].dma_addr);
-		UART_PUT_RCR(port, PDC_BUFFER_SIZE);
-
-		UART_PUT_RNPR(port, atmel_port->pdc_rx[1].dma_addr);
-		UART_PUT_RNCR(port, PDC_BUFFER_SIZE);
+	if (atmel_port->prepare_rx) {
+		retval = atmel_port->prepare_rx(port);
+		if (retval < 0)
+			atmel_set_ops(port);
 	}
-	if (atmel_use_dma_tx(port)) {
-		struct atmel_dma_buffer *pdc = &atmel_port->pdc_tx;
-		struct circ_buf *xmit = &port->state->xmit;
 
-		pdc->buf = xmit->buf;
-		pdc->dma_addr = dma_map_single(port->dev,
-					       pdc->buf,
-					       UART_XMIT_SIZE,
-					       DMA_TO_DEVICE);
-		pdc->dma_size = UART_XMIT_SIZE;
-		pdc->ofs = 0;
+	if (atmel_port->prepare_tx) {
+		retval = atmel_port->prepare_tx(port);
+		if (retval < 0)
+			atmel_set_ops(port);
 	}
-
 	/*
 	 * If there is a specific "open" function (to register
 	 * control line interrupts)
@@ -1000,14 +1590,38 @@ static int atmel_startup(struct uart_port *port)
 	/* enable xmit & rcvr */
 	UART_PUT_CR(port, ATMEL_US_TXEN | ATMEL_US_RXEN);
 
-	if (atmel_use_dma_rx(port)) {
+	if (atmel_use_pdc_rx(port)) {
 		/* set UART timeout */
-		UART_PUT_RTOR(port, PDC_RX_TIMEOUT);
-		UART_PUT_CR(port, ATMEL_US_STTTO);
-
-		UART_PUT_IER(port, ATMEL_US_ENDRX | ATMEL_US_TIMEOUT);
+		if (!atmel_port->is_usart) {
+			setup_timer(&atmel_port->uart_timer,
+					atmel_uart_timer_callback,
+					(unsigned long)port);
+			mod_timer(&atmel_port->uart_timer,
+					jiffies + uart_poll_timeout(port));
+		/* set USART timeout */
+		} else {
+			UART_PUT_RTOR(port, PDC_RX_TIMEOUT);
+			UART_PUT_CR(port, ATMEL_US_STTTO);
+
+			UART_PUT_IER(port, ATMEL_US_ENDRX | ATMEL_US_TIMEOUT);
+		}
 		/* enable PDC controller */
 		UART_PUT_PTCR(port, ATMEL_PDC_RXTEN);
+	} else if (atmel_use_dma_rx(port)) {
+		/* set UART timeout */
+		if (!atmel_port->is_usart) {
+			setup_timer(&atmel_port->uart_timer,
+					atmel_uart_timer_callback,
+					(unsigned long)port);
+			mod_timer(&atmel_port->uart_timer,
+					jiffies + uart_poll_timeout(port));
+		/* set USART timeout */
+		} else {
+			UART_PUT_RTOR(port, PDC_RX_TIMEOUT);
+			UART_PUT_CR(port, ATMEL_US_STTTO);
+
+			UART_PUT_IER(port, ATMEL_US_TIMEOUT);
+		}
 	} else {
 		/* enable receive only */
 		UART_PUT_IER(port, ATMEL_US_RXRDY);
@@ -1031,27 +1645,10 @@ static void atmel_shutdown(struct uart_port *port)
 	/*
 	 * Shut-down the DMA.
 	 */
-	if (atmel_use_dma_rx(port)) {
-		int i;
-
-		for (i = 0; i < 2; i++) {
-			struct atmel_dma_buffer *pdc = &atmel_port->pdc_rx[i];
-
-			dma_unmap_single(port->dev,
-					 pdc->dma_addr,
-					 pdc->dma_size,
-					 DMA_FROM_DEVICE);
-			kfree(pdc->buf);
-		}
-	}
-	if (atmel_use_dma_tx(port)) {
-		struct atmel_dma_buffer *pdc = &atmel_port->pdc_tx;
-
-		dma_unmap_single(port->dev,
-				 pdc->dma_addr,
-				 pdc->dma_size,
-				 DMA_TO_DEVICE);
-	}
+	if (atmel_port->release_rx)
+		atmel_port->release_rx(port);
+	if (atmel_port->release_tx)
+		atmel_port->release_tx(port);
 
 	/*
 	 * Disable all interrupts, port and break condition.
@@ -1080,7 +1677,7 @@ static void atmel_flush_buffer(struct uart_port *port)
 {
 	struct atmel_uart_port *atmel_port = to_atmel_uart_port(port);
 
-	if (atmel_use_dma_tx(port)) {
+	if (atmel_use_pdc_tx(port)) {
 		UART_PUT_TCR(port, 0);
 		atmel_port->pdc_tx.ofs = 0;
 	}
@@ -1193,7 +1790,7 @@ static void atmel_set_termios(struct uart_port *port, struct ktermios *termios,
 	if (termios->c_iflag & (BRKINT | PARMRK))
 		port->read_status_mask |= ATMEL_US_RXBRK;
 
-	if (atmel_use_dma_rx(port))
+	if (atmel_use_pdc_rx(port))
 		/* need to enable error interrupts */
 		UART_PUT_IER(port, port->read_status_mask);
 
@@ -1423,38 +2020,6 @@ static struct uart_ops atmel_pops = {
 #endif
 };
 
-static void atmel_of_init_port(struct atmel_uart_port *atmel_port,
-					 struct device_node *np)
-{
-	u32 rs485_delay[2];
-
-	/* DMA/PDC usage specification */
-	if (of_get_property(np, "atmel,use-dma-rx", NULL))
-		atmel_port->use_dma_rx	= 1;
-	else
-		atmel_port->use_dma_rx	= 0;
-	if (of_get_property(np, "atmel,use-dma-tx", NULL))
-		atmel_port->use_dma_tx	= 1;
-	else
-		atmel_port->use_dma_tx	= 0;
-
-	/* rs485 properties */
-	if (of_property_read_u32_array(np, "rs485-rts-delay",
-					    rs485_delay, 2) == 0) {
-		struct serial_rs485 *rs485conf = &atmel_port->rs485;
-
-		rs485conf->delay_rts_before_send = rs485_delay[0];
-		rs485conf->delay_rts_after_send = rs485_delay[1];
-		rs485conf->flags = 0;
-
-		if (of_get_property(np, "rs485-rx-during-tx", NULL))
-			rs485conf->flags |= SER_RS485_RX_DURING_TX;
-
-		if (of_get_property(np, "linux,rs485-enabled-at-boot-time", NULL))
-			rs485conf->flags |= SER_RS485_ENABLED;
-	}
-}
-
 /*
  * Configure the port from the platform device resource info.
  */
@@ -1463,15 +2028,12 @@ static int atmel_init_port(struct atmel_uart_port *atmel_port,
 {
 	int ret;
 	struct uart_port *port = &atmel_port->uart;
-	struct atmel_uart_data *pdata = pdev->dev.platform_data;
+	struct atmel_uart_data *pdata = dev_get_platdata(&pdev->dev);
 
-	if (pdev->dev.of_node) {
-		atmel_of_init_port(atmel_port, pdev->dev.of_node);
-	} else {
-		atmel_port->use_dma_rx	= pdata->use_dma_rx;
-		atmel_port->use_dma_tx	= pdata->use_dma_tx;
-		atmel_port->rs485	= pdata->rs485;
-	}
+	if (!atmel_init_property(atmel_port, pdev))
+		atmel_set_ops(port);
+
+	atmel_init_rs485(atmel_port, pdev);
 
 	port->iotype		= UPIO_MEM;
 	port->flags		= UPF_BOOT_AUTOCONF;
@@ -1516,7 +2078,7 @@ static int atmel_init_port(struct atmel_uart_port *atmel_port,
 	/* Use TXEMPTY for interrupt when rs485 else TXRDY or ENDTX|TXBUFE */
 	if (atmel_port->rs485.flags & SER_RS485_ENABLED)
 		atmel_port->tx_done_mask = ATMEL_US_TXEMPTY;
-	else if (atmel_use_dma_tx(port)) {
+	else if (atmel_use_pdc_tx(port)) {
 		port->fifosize = PDC_BUFFER_SIZE;
 		atmel_port->tx_done_mask = ATMEL_US_ENDTX | ATMEL_US_TXBUFE;
 	} else {
@@ -1664,7 +2226,7 @@ static int __init atmel_console_init(void)
 	int ret;
 	if (atmel_default_console_device) {
 		struct atmel_uart_data *pdata =
-			atmel_default_console_device->dev.platform_data;
+			dev_get_platdata(&atmel_default_console_device->dev);
 		int id = pdata->num;
 		struct atmel_uart_port *port = &atmel_ports[id];
 
@@ -1772,10 +2334,9 @@ static int atmel_serial_probe(struct platform_device *pdev)
 {
 	struct atmel_uart_port *port;
 	struct device_node *np = pdev->dev.of_node;
-	struct atmel_uart_data *pdata = pdev->dev.platform_data;
+	struct atmel_uart_data *pdata = dev_get_platdata(&pdev->dev);
 	void *data;
 	int ret = -ENODEV;
-	struct pinctrl *pinctrl;
 
 	BUILD_BUG_ON(ATMEL_SERIAL_RINGSIZE & (ATMEL_SERIAL_RINGSIZE - 1));
 
@@ -1809,13 +2370,7 @@ static int atmel_serial_probe(struct platform_device *pdev)
 	if (ret)
 		goto err;
 
-	pinctrl = devm_pinctrl_get_select_default(&pdev->dev);
-	if (IS_ERR(pinctrl)) {
-		ret = PTR_ERR(pinctrl);
-		goto err;
-	}
-
-	if (!atmel_use_dma_rx(&port->uart)) {
+	if (!atmel_use_pdc_rx(&port->uart)) {
 		ret = -ENOMEM;
 		data = kmalloc(sizeof(struct atmel_uart_char)
 				* ATMEL_SERIAL_RINGSIZE, GFP_KERNEL);
@@ -1847,6 +2402,13 @@ static int atmel_serial_probe(struct platform_device *pdev)
 		UART_PUT_CR(&port->uart, ATMEL_US_RTSEN);
 	}
 
+	/*
+	 * Get port name of usart or uart
+	 */
+	ret = atmel_get_ip_name(&port->uart);
+	if (ret < 0)
+		goto err_add_port;
+
 	return 0;
 
 err_add_port:
@@ -1868,7 +2430,6 @@ static int atmel_serial_remove(struct platform_device *pdev)
 	int ret = 0;
 
 	device_init_wakeup(&pdev->dev, 0);
-	platform_set_drvdata(pdev, NULL);
 
 	ret = uart_remove_one_port(&atmel_uart, port);
 
diff --git a/drivers/tty/serial/bcm63xx_uart.c b/drivers/tty/serial/bcm63xx_uart.c
index 6fa2ae77fff..649d5129c4b 100644
--- a/drivers/tty/serial/bcm63xx_uart.c
+++ b/drivers/tty/serial/bcm63xx_uart.c
@@ -302,7 +302,9 @@ static void bcm_uart_do_rx(struct uart_port *port)
 
 	} while (--max_count);
 
+	spin_unlock(&port->lock);
 	tty_flip_buffer_push(tty_port);
+	spin_lock(&port->lock);
 }
 
 /*
@@ -852,7 +854,6 @@ static int bcm_uart_remove(struct platform_device *pdev)
 
 	port = platform_get_drvdata(pdev);
 	uart_remove_one_port(&bcm_uart_driver, port);
-	platform_set_drvdata(pdev, NULL);
 	/* mark port as free */
 	ports[pdev->id].membase = 0;
 	return 0;
diff --git a/drivers/tty/serial/bfin_sport_uart.c b/drivers/tty/serial/bfin_sport_uart.c
index 487c173b0f7..87636cc61a2 100644
--- a/drivers/tty/serial/bfin_sport_uart.c
+++ b/drivers/tty/serial/bfin_sport_uart.c
@@ -161,11 +161,12 @@ static irqreturn_t sport_uart_rx_irq(int irq, void *dev_id)
 		if (!uart_handle_sysrq_char(&up->port, ch))
 			tty_insert_flip_char(port, ch, TTY_NORMAL);
 	}
-	/* XXX this won't deadlock with lowlat? */
-	tty_flip_buffer_push(port);
 
 	spin_unlock(&up->port.lock);
 
+	/* XXX this won't deadlock with lowlat? */
+	tty_flip_buffer_push(port);
+
 	return IRQ_HANDLED;
 }
 
@@ -766,7 +767,8 @@ static int sport_uart_probe(struct platform_device *pdev)
 		}
 
 		ret = peripheral_request_list(
-			(unsigned short *)pdev->dev.platform_data, DRV_NAME);
+			(unsigned short *)dev_get_platdata(&pdev->dev),
+			DRV_NAME);
 		if (ret) {
 			dev_err(&pdev->dev,
 				"Fail to request SPORT peripherals\n");
@@ -843,7 +845,7 @@ out_error_unmap:
 		iounmap(sport->port.membase);
 out_error_free_peripherals:
 		peripheral_free_list(
-			(unsigned short *)pdev->dev.platform_data);
+			(unsigned short *)dev_get_platdata(&pdev->dev));
 out_error_free_mem:
 		kfree(sport);
 		bfin_sport_uart_ports[pdev->id] = NULL;
@@ -863,7 +865,7 @@ static int sport_uart_remove(struct platform_device *pdev)
 		uart_remove_one_port(&sport_uart_reg, &sport->port);
 		iounmap(sport->port.membase);
 		peripheral_free_list(
-			(unsigned short *)pdev->dev.platform_data);
+			(unsigned short *)dev_get_platdata(&pdev->dev));
 		kfree(sport);
 		bfin_sport_uart_ports[pdev->id] = NULL;
 	}
@@ -883,7 +885,7 @@ static struct platform_driver sport_uart_driver = {
 };
 
 #ifdef CONFIG_SERIAL_BFIN_SPORT_CONSOLE
-static __initdata struct early_platform_driver early_sport_uart_driver = {
+static struct early_platform_driver early_sport_uart_driver __initdata = {
 	.class_str = CLASS_BFIN_SPORT_CONSOLE,
 	.pdrv = &sport_uart_driver,
 	.requested_id = EARLY_PLATFORM_ID_UNSET,
diff --git a/drivers/tty/serial/bfin_uart.c b/drivers/tty/serial/bfin_uart.c
index 26a3be7ced7..3c75e8e0402 100644
--- a/drivers/tty/serial/bfin_uart.c
+++ b/drivers/tty/serial/bfin_uart.c
@@ -41,10 +41,6 @@
 # undef CONFIG_EARLY_PRINTK
 #endif
 
-#ifdef CONFIG_SERIAL_BFIN_MODULE
-# undef CONFIG_EARLY_PRINTK
-#endif
-
 /* UART name and device definitions */
 #define BFIN_SERIAL_DEV_NAME	"ttyBF"
 #define BFIN_SERIAL_MAJOR	204
@@ -1180,7 +1176,7 @@ bfin_earlyprintk_console_write(struct console *co, const char *s, unsigned int c
  * don't let the common infrastructure play with things. (see calls to setup
  * & earlysetup in ./kernel/printk.c:register_console()
  */
-static struct __initdata console bfin_early_serial_console = {
+static struct console bfin_early_serial_console __initdata = {
 	.name = "early_BFuart",
 	.write = bfin_earlyprintk_console_write,
 	.device = uart_console_device,
@@ -1244,7 +1240,8 @@ static int bfin_serial_probe(struct platform_device *pdev)
 			 */
 #endif
 		ret = peripheral_request_list(
-			(unsigned short *)pdev->dev.platform_data, DRIVER_NAME);
+			(unsigned short *)dev_get_platdata(&pdev->dev),
+			DRIVER_NAME);
 		if (ret) {
 			dev_err(&pdev->dev,
 				"fail to request bfin serial peripherals\n");
@@ -1362,7 +1359,7 @@ out_error_unmap:
 		iounmap(uart->port.membase);
 out_error_free_peripherals:
 		peripheral_free_list(
-			(unsigned short *)pdev->dev.platform_data);
+			(unsigned short *)dev_get_platdata(&pdev->dev));
 out_error_free_mem:
 		kfree(uart);
 		bfin_serial_ports[pdev->id] = NULL;
@@ -1381,7 +1378,7 @@ static int bfin_serial_remove(struct platform_device *pdev)
 		uart_remove_one_port(&bfin_serial_reg, &uart->port);
 		iounmap(uart->port.membase);
 		peripheral_free_list(
-			(unsigned short *)pdev->dev.platform_data);
+			(unsigned short *)dev_get_platdata(&pdev->dev));
 		kfree(uart);
 		bfin_serial_ports[pdev->id] = NULL;
 	}
@@ -1401,7 +1398,7 @@ static struct platform_driver bfin_serial_driver = {
 };
 
 #if defined(CONFIG_SERIAL_BFIN_CONSOLE)
-static __initdata struct early_platform_driver early_bfin_serial_driver = {
+static struct early_platform_driver early_bfin_serial_driver __initdata = {
 	.class_str = CLASS_BFIN_CONSOLE,
 	.pdrv = &bfin_serial_driver,
 	.requested_id = EARLY_PLATFORM_ID_UNSET,
@@ -1436,7 +1433,7 @@ static int bfin_earlyprintk_probe(struct platform_device *pdev)
 	}
 
 	ret = peripheral_request_list(
-		(unsigned short *)pdev->dev.platform_data, DRIVER_NAME);
+		(unsigned short *)dev_get_platdata(&pdev->dev), DRIVER_NAME);
 	if (ret) {
 		dev_err(&pdev->dev,
 				"fail to request bfin serial peripherals\n");
@@ -1467,7 +1464,7 @@ static int bfin_earlyprintk_probe(struct platform_device *pdev)
 
 out_error_free_peripherals:
 	peripheral_free_list(
-		(unsigned short *)pdev->dev.platform_data);
+		(unsigned short *)dev_get_platdata(&pdev->dev));
 
 	return ret;
 }
@@ -1480,7 +1477,7 @@ static struct platform_driver bfin_earlyprintk_driver = {
 	},
 };
 
-static __initdata struct early_platform_driver early_bfin_earlyprintk_driver = {
+static struct early_platform_driver early_bfin_earlyprintk_driver __initdata = {
 	.class_str = CLASS_BFIN_EARLYPRINTK,
 	.pdrv = &bfin_earlyprintk_driver,
 	.requested_id = EARLY_PLATFORM_ID_UNSET,
diff --git a/drivers/tty/serial/clps711x.c b/drivers/tty/serial/clps711x.c
index bfb17968c8d..7e4e4088471 100644
--- a/drivers/tty/serial/clps711x.c
+++ b/drivers/tty/serial/clps711x.c
@@ -438,8 +438,7 @@ static int uart_clps711x_probe(struct platform_device *pdev)
 	s->uart_clk = devm_clk_get(&pdev->dev, "uart");
 	if (IS_ERR(s->uart_clk)) {
 		dev_err(&pdev->dev, "Can't get UART clocks\n");
-		ret = PTR_ERR(s->uart_clk);
-		goto err_out;
+		return PTR_ERR(s->uart_clk);
 	}
 
 	s->uart.owner		= THIS_MODULE;
@@ -461,7 +460,7 @@ static int uart_clps711x_probe(struct platform_device *pdev)
 	if (ret) {
 		dev_err(&pdev->dev, "Registering UART driver failed\n");
 		devm_clk_put(&pdev->dev, s->uart_clk);
-		goto err_out;
+		return ret;
 	}
 
 	for (i = 0; i < UART_CLPS711X_NR; i++) {
@@ -478,11 +477,6 @@ static int uart_clps711x_probe(struct platform_device *pdev)
 	}
 
 	return 0;
-
-err_out:
-	platform_set_drvdata(pdev, NULL);
-
-	return ret;
 }
 
 static int uart_clps711x_remove(struct platform_device *pdev)
@@ -495,7 +489,6 @@ static int uart_clps711x_remove(struct platform_device *pdev)
 
 	devm_clk_put(&pdev->dev, s->uart_clk);
 	uart_unregister_driver(&s->uart);
-	platform_set_drvdata(pdev, NULL);
 
 	return 0;
 }
diff --git a/drivers/tty/serial/cpm_uart/cpm_uart_core.c b/drivers/tty/serial/cpm_uart/cpm_uart_core.c
index f7672cae532..1a535f70dc4 100644
--- a/drivers/tty/serial/cpm_uart/cpm_uart_core.c
+++ b/drivers/tty/serial/cpm_uart/cpm_uart_core.c
@@ -1213,8 +1213,32 @@ static int cpm_uart_init_port(struct device_node *np,
 		goto out_pram;
 	}
 
-	for (i = 0; i < NUM_GPIOS; i++)
-		pinfo->gpios[i] = of_get_gpio(np, i);
+	for (i = 0; i < NUM_GPIOS; i++) {
+		int gpio;
+
+		pinfo->gpios[i] = -1;
+
+		gpio = of_get_gpio(np, i);
+
+		if (gpio_is_valid(gpio)) {
+			ret = gpio_request(gpio, "cpm_uart");
+			if (ret) {
+				pr_err("can't request gpio #%d: %d\n", i, ret);
+				continue;
+			}
+			if (i == GPIO_RTS || i == GPIO_DTR)
+				ret = gpio_direction_output(gpio, 0);
+			else
+				ret = gpio_direction_input(gpio);
+			if (ret) {
+				pr_err("can't set direction for gpio #%d: %d\n",
+					i, ret);
+				gpio_free(gpio);
+				continue;
+			}
+			pinfo->gpios[i] = gpio;
+		}
+	}
 
 #ifdef CONFIG_PPC_EARLY_DEBUG_CPM
 	udbg_putc = NULL;
diff --git a/drivers/tty/serial/efm32-uart.c b/drivers/tty/serial/efm32-uart.c
index 7d199c8e1a7..0eb5b5673ed 100644
--- a/drivers/tty/serial/efm32-uart.c
+++ b/drivers/tty/serial/efm32-uart.c
@@ -268,10 +268,10 @@ static irqreturn_t efm32_uart_rxirq(int irq, void *data)
 		handled = IRQ_HANDLED;
 	}
 
-	tty_flip_buffer_push(tport);
-
 	spin_unlock(&port->lock);
 
+	tty_flip_buffer_push(tport);
+
 	return handled;
 }
 
@@ -698,6 +698,7 @@ static int efm32_uart_probe(struct platform_device *pdev)
 {
 	struct efm32_uart_port *efm_port;
 	struct resource *res;
+	unsigned int line;
 	int ret;
 
 	efm_port = kzalloc(sizeof(*efm_port), GFP_KERNEL);
@@ -750,18 +751,21 @@ static int efm32_uart_probe(struct platform_device *pdev)
 
 		if (pdata)
 			efm_port->pdata = *pdata;
-	}
+	} else if (ret < 0)
+		goto err_probe_dt;
+
+	line = efm_port->port.line;
 
-	if (efm_port->port.line >= 0 &&
-			efm_port->port.line < ARRAY_SIZE(efm32_uart_ports))
-		efm32_uart_ports[efm_port->port.line] = efm_port;
+	if (line >= 0 && line < ARRAY_SIZE(efm32_uart_ports))
+		efm32_uart_ports[line] = efm_port;
 
 	ret = uart_add_one_port(&efm32_uart_reg, &efm_port->port);
 	if (ret) {
 		dev_dbg(&pdev->dev, "failed to add port: %d\n", ret);
 
-		if (pdev->id >= 0 && pdev->id < ARRAY_SIZE(efm32_uart_ports))
-			efm32_uart_ports[pdev->id] = NULL;
+		if (line >= 0 && line < ARRAY_SIZE(efm32_uart_ports))
+			efm32_uart_ports[line] = NULL;
+err_probe_dt:
 err_get_rxirq:
 err_too_small:
 err_get_base:
@@ -777,20 +781,19 @@ err_get_base:
 static int efm32_uart_remove(struct platform_device *pdev)
 {
 	struct efm32_uart_port *efm_port = platform_get_drvdata(pdev);
-
-	platform_set_drvdata(pdev, NULL);
+	unsigned int line = efm_port->port.line;
 
 	uart_remove_one_port(&efm32_uart_reg, &efm_port->port);
 
-	if (pdev->id >= 0 && pdev->id < ARRAY_SIZE(efm32_uart_ports))
-		efm32_uart_ports[pdev->id] = NULL;
+	if (line >= 0 && line < ARRAY_SIZE(efm32_uart_ports))
+		efm32_uart_ports[line] = NULL;
 
 	kfree(efm_port);
 
 	return 0;
 }
 
-static struct of_device_id efm32_uart_dt_ids[] = {
+static const struct of_device_id efm32_uart_dt_ids[] = {
 	{
 		.compatible = "efm32,uart",
 	}, {
diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c
index 263cfaabe9e..8978dc9a58b 100644
--- a/drivers/tty/serial/fsl_lpuart.c
+++ b/drivers/tty/serial/fsl_lpuart.c
@@ -342,8 +342,10 @@ static void lpuart_break_ctl(struct uart_port *port, int break_state)
 static void lpuart_setup_watermark(struct lpuart_port *sport)
 {
 	unsigned char val, cr2;
+	unsigned char cr2_saved;
 
 	cr2 = readb(sport->port.membase + UARTCR2);
+	cr2_saved = cr2;
 	cr2 &= ~(UARTCR2_TIE | UARTCR2_TCIE | UARTCR2_TE |
 			UARTCR2_RIE | UARTCR2_RE);
 	writeb(cr2, sport->port.membase + UARTCR2);
@@ -366,6 +368,9 @@ static void lpuart_setup_watermark(struct lpuart_port *sport)
 
 	writeb(2, sport->port.membase + UARTTWFIFO);
 	writeb(1, sport->port.membase + UARTRWFIFO);
+
+	/* Restore cr2 */
+	writeb(cr2_saved, sport->port.membase + UARTCR2);
 }
 
 static int lpuart_startup(struct uart_port *port)
@@ -858,7 +863,7 @@ static int __init lpuart_serial_init(void)
 	if (ret)
 		uart_unregister_driver(&lpuart_reg);
 
-	return 0;
+	return ret;
 }
 
 static void __exit lpuart_serial_exit(void)
diff --git a/drivers/tty/serial/icom.c b/drivers/tty/serial/icom.c
index 18ed5aebb16..d98e4334897 100644
--- a/drivers/tty/serial/icom.c
+++ b/drivers/tty/serial/icom.c
@@ -105,7 +105,7 @@ static const struct pci_device_id icom_pci_table[] = {
 	{}
 };
 
-struct lookup_proc_table start_proc[4] = {
+static struct lookup_proc_table start_proc[4] = {
 	{NULL, ICOM_CONTROL_START_A},
 	{NULL, ICOM_CONTROL_START_B},
 	{NULL, ICOM_CONTROL_START_C},
@@ -113,14 +113,14 @@ struct lookup_proc_table start_proc[4] = {
 };
 
 
-struct lookup_proc_table stop_proc[4] = {
+static struct lookup_proc_table stop_proc[4] = {
 	{NULL, ICOM_CONTROL_STOP_A},
 	{NULL, ICOM_CONTROL_STOP_B},
 	{NULL, ICOM_CONTROL_STOP_C},
 	{NULL, ICOM_CONTROL_STOP_D}
 };
 
-struct lookup_int_table int_mask_tbl[4] = {
+static struct lookup_int_table int_mask_tbl[4] = {
 	{NULL, ICOM_INT_MASK_PRC_A},
 	{NULL, ICOM_INT_MASK_PRC_B},
 	{NULL, ICOM_INT_MASK_PRC_C},
@@ -297,25 +297,25 @@ static void stop_processor(struct icom_port *icom_port)
 	spin_lock_irqsave(&icom_lock, flags);
 
 	port = icom_port->port;
+	if (port >= ARRAY_SIZE(stop_proc)) {
+		dev_err(&icom_port->adapter->pci_dev->dev,
+			"Invalid port assignment\n");
+		goto unlock;
+	}
+
 	if (port == 0 || port == 1)
 		stop_proc[port].global_control_reg = &icom_port->global_reg->control;
 	else
 		stop_proc[port].global_control_reg = &icom_port->global_reg->control_2;
 
+	temp = readl(stop_proc[port].global_control_reg);
+	temp = (temp & ~start_proc[port].processor_id) | stop_proc[port].processor_id;
+	writel(temp, stop_proc[port].global_control_reg);
 
-	if (port < 4) {
-		temp = readl(stop_proc[port].global_control_reg);
-		temp =
-			(temp & ~start_proc[port].processor_id) | stop_proc[port].processor_id;
-		writel(temp, stop_proc[port].global_control_reg);
-
-		/* write flush */
-		readl(stop_proc[port].global_control_reg);
-	} else {
-		dev_err(&icom_port->adapter->pci_dev->dev,
-                        "Invalid port assignment\n");
-	}
+	/* write flush */
+	readl(stop_proc[port].global_control_reg);
 
+unlock:
 	spin_unlock_irqrestore(&icom_lock, flags);
 }
 
@@ -328,23 +328,25 @@ static void start_processor(struct icom_port *icom_port)
 	spin_lock_irqsave(&icom_lock, flags);
 
 	port = icom_port->port;
+	if (port >= ARRAY_SIZE(start_proc)) {
+		dev_err(&icom_port->adapter->pci_dev->dev,
+			"Invalid port assignment\n");
+		goto unlock;
+	}
+
 	if (port == 0 || port == 1)
 		start_proc[port].global_control_reg = &icom_port->global_reg->control;
 	else
 		start_proc[port].global_control_reg = &icom_port->global_reg->control_2;
-	if (port < 4) {
-		temp = readl(start_proc[port].global_control_reg);
-		temp =
-			(temp & ~stop_proc[port].processor_id) | start_proc[port].processor_id;
-		writel(temp, start_proc[port].global_control_reg);
 
-		/* write flush */
-		readl(start_proc[port].global_control_reg);
-	} else {
-		dev_err(&icom_port->adapter->pci_dev->dev,
-                        "Invalid port assignment\n");
-	}
+	temp = readl(start_proc[port].global_control_reg);
+	temp = (temp & ~stop_proc[port].processor_id) | start_proc[port].processor_id;
+	writel(temp, start_proc[port].global_control_reg);
+
+	/* write flush */
+	readl(start_proc[port].global_control_reg);
 
+unlock:
 	spin_unlock_irqrestore(&icom_lock, flags);
 }
 
@@ -557,6 +559,12 @@ static int startup(struct icom_port *icom_port)
 	 */
 	spin_lock_irqsave(&icom_lock, flags);
 	port = icom_port->port;
+	if (port >= ARRAY_SIZE(int_mask_tbl)) {
+		dev_err(&icom_port->adapter->pci_dev->dev,
+			"Invalid port assignment\n");
+		goto unlock;
+	}
+
 	if (port == 0 || port == 1)
 		int_mask_tbl[port].global_int_mask = &icom_port->global_reg->int_mask;
 	else
@@ -566,17 +574,14 @@ static int startup(struct icom_port *icom_port)
 		writew(0x00FF, icom_port->int_reg);
 	else
 		writew(0x3F00, icom_port->int_reg);
-	if (port < 4) {
-		temp = readl(int_mask_tbl[port].global_int_mask);
-		writel(temp & ~int_mask_tbl[port].processor_id, int_mask_tbl[port].global_int_mask);
 
-		/* write flush */
-		readl(int_mask_tbl[port].global_int_mask);
-	} else {
-		dev_err(&icom_port->adapter->pci_dev->dev,
-                        "Invalid port assignment\n");
-	}
+	temp = readl(int_mask_tbl[port].global_int_mask);
+	writel(temp & ~int_mask_tbl[port].processor_id, int_mask_tbl[port].global_int_mask);
 
+	/* write flush */
+	readl(int_mask_tbl[port].global_int_mask);
+
+unlock:
 	spin_unlock_irqrestore(&icom_lock, flags);
 	return 0;
 }
@@ -595,21 +600,23 @@ static void shutdown(struct icom_port *icom_port)
 	 * disable all interrupts
 	 */
 	port = icom_port->port;
+	if (port >= ARRAY_SIZE(int_mask_tbl)) {
+		dev_err(&icom_port->adapter->pci_dev->dev,
+			"Invalid port assignment\n");
+		goto unlock;
+	}
 	if (port == 0 || port == 1)
 		int_mask_tbl[port].global_int_mask = &icom_port->global_reg->int_mask;
 	else
 		int_mask_tbl[port].global_int_mask = &icom_port->global_reg->int_mask_2;
 
-	if (port < 4) {
-		temp = readl(int_mask_tbl[port].global_int_mask);
-		writel(temp | int_mask_tbl[port].processor_id, int_mask_tbl[port].global_int_mask);
+	temp = readl(int_mask_tbl[port].global_int_mask);
+	writel(temp | int_mask_tbl[port].processor_id, int_mask_tbl[port].global_int_mask);
 
-		/* write flush */
-		readl(int_mask_tbl[port].global_int_mask);
-	} else {
-		dev_err(&icom_port->adapter->pci_dev->dev,
-                        "Invalid port assignment\n");
-	}
+	/* write flush */
+	readl(int_mask_tbl[port].global_int_mask);
+
+unlock:
 	spin_unlock_irqrestore(&icom_lock, flags);
 
 	/*
@@ -834,7 +841,10 @@ ignore_char:
 		status = cpu_to_le16(icom_port->statStg->rcv[rcv_buff].flags);
 	}
 	icom_port->next_rcv = rcv_buff;
+
+	spin_unlock(&icom_port->uart_port.lock);
 	tty_flip_buffer_push(port);
+	spin_lock(&icom_port->uart_port.lock);
 }
 
 static void process_interrupt(u16 port_int_reg,
@@ -1087,8 +1097,7 @@ static void icom_close(struct uart_port *port)
 
 	/* stop receiver */
 	cmdReg = readb(&ICOM_PORT->dram->CmdReg);
-	writeb(cmdReg & (unsigned char) ~CMD_RCV_ENABLE,
-	       &ICOM_PORT->dram->CmdReg);
+	writeb(cmdReg & ~CMD_RCV_ENABLE, &ICOM_PORT->dram->CmdReg);
 
 	shutdown(ICOM_PORT);
 
@@ -1567,7 +1576,7 @@ static int icom_probe(struct pci_dev *dev,
 			icom_port->uart_port.type = PORT_ICOM;
 			icom_port->uart_port.iotype = UPIO_MEM;
 			icom_port->uart_port.membase =
-					       (char *) icom_adapter->base_addr_pci;
+				(unsigned char __iomem *)icom_adapter->base_addr_pci;
 			icom_port->uart_port.fifosize = 16;
 			icom_port->uart_port.ops = &icom_ops;
 			icom_port->uart_port.line =
diff --git a/drivers/tty/serial/ifx6x60.c b/drivers/tty/serial/ifx6x60.c
index 8b1534c424a..af286e6713e 100644
--- a/drivers/tty/serial/ifx6x60.c
+++ b/drivers/tty/serial/ifx6x60.c
@@ -1008,7 +1008,7 @@ static int ifx_spi_spi_probe(struct spi_device *spi)
 		return -ENODEV;
 	}
 
-	pl_data = (struct ifx_modem_platform_data *)spi->dev.platform_data;
+	pl_data = (struct ifx_modem_platform_data *)dev_get_platdata(&spi->dev);
 	if (!pl_data) {
 		dev_err(&spi->dev, "missing platform data!");
 		return -ENODEV;
diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c
index 415cec62073..a0ebbc9ce5c 100644
--- a/drivers/tty/serial/imx.c
+++ b/drivers/tty/serial/imx.c
@@ -47,11 +47,12 @@
 #include <linux/slab.h>
 #include <linux/of.h>
 #include <linux/of_device.h>
-#include <linux/pinctrl/consumer.h>
 #include <linux/io.h>
+#include <linux/dma-mapping.h>
 
 #include <asm/irq.h>
 #include <linux/platform_data/serial-imx.h>
+#include <linux/platform_data/dma-imx.h>
 
 /* Register definitions */
 #define URXD0 0x0  /* Receiver Register */
@@ -83,6 +84,7 @@
 #define UCR1_ADBR	(1<<14) /* Auto detect baud rate */
 #define UCR1_TRDYEN	(1<<13) /* Transmitter ready interrupt enable */
 #define UCR1_IDEN	(1<<12) /* Idle condition interrupt */
+#define UCR1_ICD_REG(x) (((x) & 3) << 10) /* idle condition detect */
 #define UCR1_RRDYEN	(1<<9)	/* Recv ready interrupt enable */
 #define UCR1_RDMAEN	(1<<8)	/* Recv ready DMA enable */
 #define UCR1_IREN	(1<<7)	/* Infrared interface enable */
@@ -91,6 +93,7 @@
 #define UCR1_SNDBRK	(1<<4)	/* Send break */
 #define UCR1_TDMAEN	(1<<3)	/* Transmitter ready DMA enable */
 #define IMX1_UCR1_UARTCLKEN (1<<2) /* UART clock enabled, i.mx1 only */
+#define UCR1_ATDMAEN    (1<<2)  /* Aging DMA Timer Enable */
 #define UCR1_DOZE	(1<<1)	/* Doze */
 #define UCR1_UARTEN	(1<<0)	/* UART enabled */
 #define UCR2_ESCI	(1<<15)	/* Escape seq interrupt enable */
@@ -126,6 +129,7 @@
 #define UCR4_ENIRI	(1<<8)	/* Serial infrared interrupt enable */
 #define UCR4_WKEN	(1<<7)	/* Wake interrupt enable */
 #define UCR4_REF16	(1<<6)	/* Ref freq 16 MHz */
+#define UCR4_IDDMAEN    (1<<6)  /* DMA IDLE Condition Detected */
 #define UCR4_IRSC	(1<<5)	/* IR special case */
 #define UCR4_TCEN	(1<<3)	/* Transmit complete interrupt enable */
 #define UCR4_BKEN	(1<<2)	/* Break condition interrupt enable */
@@ -187,6 +191,7 @@
 enum imx_uart_type {
 	IMX1_UART,
 	IMX21_UART,
+	IMX6Q_UART,
 };
 
 /* device type dependent stuff */
@@ -209,6 +214,19 @@ struct imx_port {
 	struct clk		*clk_ipg;
 	struct clk		*clk_per;
 	const struct imx_uart_data *devdata;
+
+	/* DMA fields */
+	unsigned int		dma_is_inited:1;
+	unsigned int		dma_is_enabled:1;
+	unsigned int		dma_is_rxing:1;
+	unsigned int		dma_is_txing:1;
+	struct dma_chan		*dma_chan_rx, *dma_chan_tx;
+	struct scatterlist	rx_sgl, tx_sgl[2];
+	void			*rx_buf;
+	unsigned int		rx_bytes, tx_bytes;
+	struct work_struct	tsk_dma_rx, tsk_dma_tx;
+	unsigned int		dma_tx_nents;
+	wait_queue_head_t	dma_wait;
 };
 
 struct imx_port_ucrs {
@@ -232,6 +250,10 @@ static struct imx_uart_data imx_uart_devdata[] = {
 		.uts_reg = IMX21_UTS,
 		.devtype = IMX21_UART,
 	},
+	[IMX6Q_UART] = {
+		.uts_reg = IMX21_UTS,
+		.devtype = IMX6Q_UART,
+	},
 };
 
 static struct platform_device_id imx_uart_devtype[] = {
@@ -242,12 +264,16 @@ static struct platform_device_id imx_uart_devtype[] = {
 		.name = "imx21-uart",
 		.driver_data = (kernel_ulong_t) &imx_uart_devdata[IMX21_UART],
 	}, {
+		.name = "imx6q-uart",
+		.driver_data = (kernel_ulong_t) &imx_uart_devdata[IMX6Q_UART],
+	}, {
 		/* sentinel */
 	}
 };
 MODULE_DEVICE_TABLE(platform, imx_uart_devtype);
 
 static struct of_device_id imx_uart_dt_ids[] = {
+	{ .compatible = "fsl,imx6q-uart", .data = &imx_uart_devdata[IMX6Q_UART], },
 	{ .compatible = "fsl,imx1-uart", .data = &imx_uart_devdata[IMX1_UART], },
 	{ .compatible = "fsl,imx21-uart", .data = &imx_uart_devdata[IMX21_UART], },
 	{ /* sentinel */ }
@@ -269,6 +295,10 @@ static inline int is_imx21_uart(struct imx_port *sport)
 	return sport->devdata->devtype == IMX21_UART;
 }
 
+static inline int is_imx6q_uart(struct imx_port *sport)
+{
+	return sport->devdata->devtype == IMX6Q_UART;
+}
 /*
  * Save and restore functions for UCR1, UCR2 and UCR3 registers
  */
@@ -387,6 +417,13 @@ static void imx_stop_tx(struct uart_port *port)
 		return;
 	}
 
+	/*
+	 * We are maybe in the SMP context, so if the DMA TX thread is running
+	 * on other cpu, we have to wait for it to finish.
+	 */
+	if (sport->dma_is_enabled && sport->dma_is_txing)
+		return;
+
 	temp = readl(sport->port.membase + UCR1);
 	writel(temp & ~UCR1_TXMPTYEN, sport->port.membase + UCR1);
 }
@@ -399,6 +436,13 @@ static void imx_stop_rx(struct uart_port *port)
 	struct imx_port *sport = (struct imx_port *)port;
 	unsigned long temp;
 
+	/*
+	 * We are maybe in the SMP context, so if the DMA TX thread is running
+	 * on other cpu, we have to wait for it to finish.
+	 */
+	if (sport->dma_is_enabled && sport->dma_is_rxing)
+		return;
+
 	temp = readl(sport->port.membase + UCR2);
 	writel(temp & ~UCR2_RXEN, sport->port.membase + UCR2);
 }
@@ -434,6 +478,95 @@ static inline void imx_transmit_buffer(struct imx_port *sport)
 		imx_stop_tx(&sport->port);
 }
 
+static void dma_tx_callback(void *data)
+{
+	struct imx_port *sport = data;
+	struct scatterlist *sgl = &sport->tx_sgl[0];
+	struct circ_buf *xmit = &sport->port.state->xmit;
+	unsigned long flags;
+
+	dma_unmap_sg(sport->port.dev, sgl, sport->dma_tx_nents, DMA_TO_DEVICE);
+
+	sport->dma_is_txing = 0;
+
+	/* update the stat */
+	spin_lock_irqsave(&sport->port.lock, flags);
+	xmit->tail = (xmit->tail + sport->tx_bytes) & (UART_XMIT_SIZE - 1);
+	sport->port.icount.tx += sport->tx_bytes;
+	spin_unlock_irqrestore(&sport->port.lock, flags);
+
+	dev_dbg(sport->port.dev, "we finish the TX DMA.\n");
+
+	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+		uart_write_wakeup(&sport->port);
+
+	if (waitqueue_active(&sport->dma_wait)) {
+		wake_up(&sport->dma_wait);
+		dev_dbg(sport->port.dev, "exit in %s.\n", __func__);
+		return;
+	}
+
+	schedule_work(&sport->tsk_dma_tx);
+}
+
+static void dma_tx_work(struct work_struct *w)
+{
+	struct imx_port *sport = container_of(w, struct imx_port, tsk_dma_tx);
+	struct circ_buf *xmit = &sport->port.state->xmit;
+	struct scatterlist *sgl = sport->tx_sgl;
+	struct dma_async_tx_descriptor *desc;
+	struct dma_chan	*chan = sport->dma_chan_tx;
+	struct device *dev = sport->port.dev;
+	enum dma_status status;
+	unsigned long flags;
+	int ret;
+
+	status = chan->device->device_tx_status(chan, (dma_cookie_t)0, NULL);
+	if (DMA_IN_PROGRESS == status)
+		return;
+
+	spin_lock_irqsave(&sport->port.lock, flags);
+	sport->tx_bytes = uart_circ_chars_pending(xmit);
+	if (sport->tx_bytes == 0) {
+		spin_unlock_irqrestore(&sport->port.lock, flags);
+		return;
+	}
+
+	if (xmit->tail > xmit->head) {
+		sport->dma_tx_nents = 2;
+		sg_init_table(sgl, 2);
+		sg_set_buf(sgl, xmit->buf + xmit->tail,
+				UART_XMIT_SIZE - xmit->tail);
+		sg_set_buf(sgl + 1, xmit->buf, xmit->head);
+	} else {
+		sport->dma_tx_nents = 1;
+		sg_init_one(sgl, xmit->buf + xmit->tail, sport->tx_bytes);
+	}
+	spin_unlock_irqrestore(&sport->port.lock, flags);
+
+	ret = dma_map_sg(dev, sgl, sport->dma_tx_nents, DMA_TO_DEVICE);
+	if (ret == 0) {
+		dev_err(dev, "DMA mapping error for TX.\n");
+		return;
+	}
+	desc = dmaengine_prep_slave_sg(chan, sgl, sport->dma_tx_nents,
+					DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT);
+	if (!desc) {
+		dev_err(dev, "We cannot prepare for the TX slave dma!\n");
+		return;
+	}
+	desc->callback = dma_tx_callback;
+	desc->callback_param = sport;
+
+	dev_dbg(dev, "TX: prepare to send %lu bytes by DMA.\n",
+			uart_circ_chars_pending(xmit));
+	/* fire it */
+	sport->dma_is_txing = 1;
+	dmaengine_submit(desc);
+	dma_async_issue_pending(chan);
+	return;
+}
+
 /*
  * interrupts disabled on entry
  */
@@ -460,8 +593,10 @@ static void imx_start_tx(struct uart_port *port)
 	temp |= UCR4_OREN;
 	writel(temp, sport->port.membase + UCR4);
 
-	temp = readl(sport->port.membase + UCR1);
-	writel(temp | UCR1_TXMPTYEN, sport->port.membase + UCR1);
+	if (!sport->dma_is_enabled) {
+		temp = readl(sport->port.membase + UCR1);
+		writel(temp | UCR1_TXMPTYEN, sport->port.membase + UCR1);
+	}
 
 	if (USE_IRDA(sport)) {
 		temp = readl(sport->port.membase + UCR1);
@@ -473,6 +608,15 @@ static void imx_start_tx(struct uart_port *port)
 		writel(temp, sport->port.membase + UCR4);
 	}
 
+	if (sport->dma_is_enabled) {
+		/*
+		 * We may in the interrupt context, so arise a work_struct to
+		 * do the real job.
+		 */
+		schedule_work(&sport->tsk_dma_tx);
+		return;
+	}
+
 	if (readl(sport->port.membase + uts_reg(sport)) & UTS_TXEMPTY)
 		imx_transmit_buffer(sport);
 }
@@ -588,6 +732,28 @@ out:
 	return IRQ_HANDLED;
 }
 
+/*
+ * If the RXFIFO is filled with some data, and then we
+ * arise a DMA operation to receive them.
+ */
+static void imx_dma_rxint(struct imx_port *sport)
+{
+	unsigned long temp;
+
+	temp = readl(sport->port.membase + USR2);
+	if ((temp & USR2_RDR) && !sport->dma_is_rxing) {
+		sport->dma_is_rxing = 1;
+
+		/* disable the `Recerver Ready Interrrupt` */
+		temp = readl(sport->port.membase + UCR1);
+		temp &= ~(UCR1_RRDYEN);
+		writel(temp, sport->port.membase + UCR1);
+
+		/* tell the DMA to receive the data. */
+		schedule_work(&sport->tsk_dma_rx);
+	}
+}
+
 static irqreturn_t imx_int(int irq, void *dev_id)
 {
 	struct imx_port *sport = dev_id;
@@ -596,8 +762,12 @@ static irqreturn_t imx_int(int irq, void *dev_id)
 
 	sts = readl(sport->port.membase + USR1);
 
-	if (sts & USR1_RRDY)
-		imx_rxint(irq, dev_id);
+	if (sts & USR1_RRDY) {
+		if (sport->dma_is_enabled)
+			imx_dma_rxint(sport);
+		else
+			imx_rxint(irq, dev_id);
+	}
 
 	if (sts & USR1_TRDY &&
 			readl(sport->port.membase + UCR1) & UCR1_TXMPTYEN)
@@ -654,7 +824,8 @@ static void imx_set_mctrl(struct uart_port *port, unsigned int mctrl)
 	temp = readl(sport->port.membase + UCR2) & ~UCR2_CTS;
 
 	if (mctrl & TIOCM_RTS)
-		temp |= UCR2_CTS;
+		if (!sport->dma_is_enabled)
+			temp |= UCR2_CTS;
 
 	writel(temp, sport->port.membase + UCR2);
 }
@@ -693,6 +864,226 @@ static int imx_setup_ufcr(struct imx_port *sport, unsigned int mode)
 	return 0;
 }
 
+#define RX_BUF_SIZE	(PAGE_SIZE)
+static int start_rx_dma(struct imx_port *sport);
+static void dma_rx_work(struct work_struct *w)
+{
+	struct imx_port *sport = container_of(w, struct imx_port, tsk_dma_rx);
+	struct tty_port *port = &sport->port.state->port;
+
+	if (sport->rx_bytes) {
+		tty_insert_flip_string(port, sport->rx_buf, sport->rx_bytes);
+		tty_flip_buffer_push(port);
+		sport->rx_bytes = 0;
+	}
+
+	if (sport->dma_is_rxing)
+		start_rx_dma(sport);
+}
+
+static void imx_rx_dma_done(struct imx_port *sport)
+{
+	unsigned long temp;
+
+	/* Enable this interrupt when the RXFIFO is empty. */
+	temp = readl(sport->port.membase + UCR1);
+	temp |= UCR1_RRDYEN;
+	writel(temp, sport->port.membase + UCR1);
+
+	sport->dma_is_rxing = 0;
+
+	/* Is the shutdown waiting for us? */
+	if (waitqueue_active(&sport->dma_wait))
+		wake_up(&sport->dma_wait);
+}
+
+/*
+ * There are three kinds of RX DMA interrupts(such as in the MX6Q):
+ *   [1] the RX DMA buffer is full.
+ *   [2] the Aging timer expires(wait for 8 bytes long)
+ *   [3] the Idle Condition Detect(enabled the UCR4_IDDMAEN).
+ *
+ * The [2] is trigger when a character was been sitting in the FIFO
+ * meanwhile [3] can wait for 32 bytes long when the RX line is
+ * on IDLE state and RxFIFO is empty.
+ */
+static void dma_rx_callback(void *data)
+{
+	struct imx_port *sport = data;
+	struct dma_chan	*chan = sport->dma_chan_rx;
+	struct scatterlist *sgl = &sport->rx_sgl;
+	struct dma_tx_state state;
+	enum dma_status status;
+	unsigned int count;
+
+	/* unmap it first */
+	dma_unmap_sg(sport->port.dev, sgl, 1, DMA_FROM_DEVICE);
+
+	status = chan->device->device_tx_status(chan, (dma_cookie_t)0, &state);
+	count = RX_BUF_SIZE - state.residue;
+	dev_dbg(sport->port.dev, "We get %d bytes.\n", count);
+
+	if (count) {
+		sport->rx_bytes = count;
+		schedule_work(&sport->tsk_dma_rx);
+	} else
+		imx_rx_dma_done(sport);
+}
+
+static int start_rx_dma(struct imx_port *sport)
+{
+	struct scatterlist *sgl = &sport->rx_sgl;
+	struct dma_chan	*chan = sport->dma_chan_rx;
+	struct device *dev = sport->port.dev;
+	struct dma_async_tx_descriptor *desc;
+	int ret;
+
+	sg_init_one(sgl, sport->rx_buf, RX_BUF_SIZE);
+	ret = dma_map_sg(dev, sgl, 1, DMA_FROM_DEVICE);
+	if (ret == 0) {
+		dev_err(dev, "DMA mapping error for RX.\n");
+		return -EINVAL;
+	}
+	desc = dmaengine_prep_slave_sg(chan, sgl, 1, DMA_DEV_TO_MEM,
+					DMA_PREP_INTERRUPT);
+	if (!desc) {
+		dev_err(dev, "We cannot prepare for the RX slave dma!\n");
+		return -EINVAL;
+	}
+	desc->callback = dma_rx_callback;
+	desc->callback_param = sport;
+
+	dev_dbg(dev, "RX: prepare for the DMA.\n");
+	dmaengine_submit(desc);
+	dma_async_issue_pending(chan);
+	return 0;
+}
+
+static void imx_uart_dma_exit(struct imx_port *sport)
+{
+	if (sport->dma_chan_rx) {
+		dma_release_channel(sport->dma_chan_rx);
+		sport->dma_chan_rx = NULL;
+
+		kfree(sport->rx_buf);
+		sport->rx_buf = NULL;
+	}
+
+	if (sport->dma_chan_tx) {
+		dma_release_channel(sport->dma_chan_tx);
+		sport->dma_chan_tx = NULL;
+	}
+
+	sport->dma_is_inited = 0;
+}
+
+static int imx_uart_dma_init(struct imx_port *sport)
+{
+	struct dma_slave_config slave_config = {};
+	struct device *dev = sport->port.dev;
+	int ret;
+
+	/* Prepare for RX : */
+	sport->dma_chan_rx = dma_request_slave_channel(dev, "rx");
+	if (!sport->dma_chan_rx) {
+		dev_dbg(dev, "cannot get the DMA channel.\n");
+		ret = -EINVAL;
+		goto err;
+	}
+
+	slave_config.direction = DMA_DEV_TO_MEM;
+	slave_config.src_addr = sport->port.mapbase + URXD0;
+	slave_config.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
+	slave_config.src_maxburst = RXTL;
+	ret = dmaengine_slave_config(sport->dma_chan_rx, &slave_config);
+	if (ret) {
+		dev_err(dev, "error in RX dma configuration.\n");
+		goto err;
+	}
+
+	sport->rx_buf = kzalloc(PAGE_SIZE, GFP_KERNEL);
+	if (!sport->rx_buf) {
+		dev_err(dev, "cannot alloc DMA buffer.\n");
+		ret = -ENOMEM;
+		goto err;
+	}
+	sport->rx_bytes = 0;
+
+	/* Prepare for TX : */
+	sport->dma_chan_tx = dma_request_slave_channel(dev, "tx");
+	if (!sport->dma_chan_tx) {
+		dev_err(dev, "cannot get the TX DMA channel!\n");
+		ret = -EINVAL;
+		goto err;
+	}
+
+	slave_config.direction = DMA_MEM_TO_DEV;
+	slave_config.dst_addr = sport->port.mapbase + URTX0;
+	slave_config.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
+	slave_config.dst_maxburst = TXTL;
+	ret = dmaengine_slave_config(sport->dma_chan_tx, &slave_config);
+	if (ret) {
+		dev_err(dev, "error in TX dma configuration.");
+		goto err;
+	}
+
+	sport->dma_is_inited = 1;
+
+	return 0;
+err:
+	imx_uart_dma_exit(sport);
+	return ret;
+}
+
+static void imx_enable_dma(struct imx_port *sport)
+{
+	unsigned long temp;
+	struct tty_port *port = &sport->port.state->port;
+
+	port->low_latency = 1;
+	INIT_WORK(&sport->tsk_dma_tx, dma_tx_work);
+	INIT_WORK(&sport->tsk_dma_rx, dma_rx_work);
+	init_waitqueue_head(&sport->dma_wait);
+
+	/* set UCR1 */
+	temp = readl(sport->port.membase + UCR1);
+	temp |= UCR1_RDMAEN | UCR1_TDMAEN | UCR1_ATDMAEN |
+		/* wait for 32 idle frames for IDDMA interrupt */
+		UCR1_ICD_REG(3);
+	writel(temp, sport->port.membase + UCR1);
+
+	/* set UCR4 */
+	temp = readl(sport->port.membase + UCR4);
+	temp |= UCR4_IDDMAEN;
+	writel(temp, sport->port.membase + UCR4);
+
+	sport->dma_is_enabled = 1;
+}
+
+static void imx_disable_dma(struct imx_port *sport)
+{
+	unsigned long temp;
+	struct tty_port *port = &sport->port.state->port;
+
+	/* clear UCR1 */
+	temp = readl(sport->port.membase + UCR1);
+	temp &= ~(UCR1_RDMAEN | UCR1_TDMAEN | UCR1_ATDMAEN);
+	writel(temp, sport->port.membase + UCR1);
+
+	/* clear UCR2 */
+	temp = readl(sport->port.membase + UCR2);
+	temp &= ~(UCR2_CTSC | UCR2_CTS);
+	writel(temp, sport->port.membase + UCR2);
+
+	/* clear UCR4 */
+	temp = readl(sport->port.membase + UCR4);
+	temp &= ~UCR4_IDDMAEN;
+	writel(temp, sport->port.membase + UCR4);
+
+	sport->dma_is_enabled = 0;
+	port->low_latency = 0;
+}
+
 /* half the RX buffer size */
 #define CTSTL 16
 
@@ -702,15 +1093,13 @@ static int imx_startup(struct uart_port *port)
 	int retval;
 	unsigned long flags, temp;
 
-	if (!uart_console(port)) {
-		retval = clk_prepare_enable(sport->clk_per);
-		if (retval)
-			goto error_out1;
-		retval = clk_prepare_enable(sport->clk_ipg);
-		if (retval) {
-			clk_disable_unprepare(sport->clk_per);
-			goto error_out1;
-		}
+	retval = clk_prepare_enable(sport->clk_per);
+	if (retval)
+		goto error_out1;
+	retval = clk_prepare_enable(sport->clk_ipg);
+	if (retval) {
+		clk_disable_unprepare(sport->clk_per);
+		goto error_out1;
 	}
 
 	imx_setup_ufcr(sport, 0);
@@ -803,7 +1192,7 @@ static int imx_startup(struct uart_port *port)
 		}
 	}
 
-	if (is_imx21_uart(sport)) {
+	if (!is_imx1_uart(sport)) {
 		temp = readl(sport->port.membase + UCR3);
 		temp |= IMX21_UCR3_RXDMUXSEL;
 		writel(temp, sport->port.membase + UCR3);
@@ -833,7 +1222,7 @@ static int imx_startup(struct uart_port *port)
 
 	if (USE_IRDA(sport)) {
 		struct imxuart_platform_data *pdata;
-		pdata = sport->port.dev->platform_data;
+		pdata = dev_get_platdata(sport->port.dev);
 		sport->irda_inv_rx = pdata->irda_inv_rx;
 		sport->irda_inv_tx = pdata->irda_inv_tx;
 		sport->trcv_delay = pdata->transceiver_delay;
@@ -859,6 +1248,15 @@ static void imx_shutdown(struct uart_port *port)
 	unsigned long temp;
 	unsigned long flags;
 
+	if (sport->dma_is_enabled) {
+		/* We have to wait for the DMA to finish. */
+		wait_event(sport->dma_wait,
+			!sport->dma_is_rxing && !sport->dma_is_txing);
+		imx_stop_rx(port);
+		imx_disable_dma(sport);
+		imx_uart_dma_exit(sport);
+	}
+
 	spin_lock_irqsave(&sport->port.lock, flags);
 	temp = readl(sport->port.membase + UCR2);
 	temp &= ~(UCR2_TXEN);
@@ -867,7 +1265,7 @@ static void imx_shutdown(struct uart_port *port)
 
 	if (USE_IRDA(sport)) {
 		struct imxuart_platform_data *pdata;
-		pdata = sport->port.dev->platform_data;
+		pdata = dev_get_platdata(sport->port.dev);
 		if (pdata->irda_enable)
 			pdata->irda_enable(0);
 	}
@@ -901,10 +1299,8 @@ static void imx_shutdown(struct uart_port *port)
 	writel(temp, sport->port.membase + UCR1);
 	spin_unlock_irqrestore(&sport->port.lock, flags);
 
-	if (!uart_console(&sport->port)) {
-		clk_disable_unprepare(sport->clk_per);
-		clk_disable_unprepare(sport->clk_ipg);
-	}
+	clk_disable_unprepare(sport->clk_per);
+	clk_disable_unprepare(sport->clk_ipg);
 }
 
 static void
@@ -947,6 +1343,11 @@ imx_set_termios(struct uart_port *port, struct ktermios *termios,
 		if (sport->have_rtscts) {
 			ucr2 &= ~UCR2_IRTS;
 			ucr2 |= UCR2_CTSC;
+
+			/* Can we enable the DMA support? */
+			if (is_imx6q_uart(sport) && !uart_console(port)
+				&& !sport->dma_is_inited)
+				imx_uart_dma_init(sport);
 		} else {
 			termios->c_cflag &= ~CRTSCTS;
 		}
@@ -1020,6 +1421,11 @@ imx_set_termios(struct uart_port *port, struct ktermios *termios,
 		 */
 		div = 1;
 	} else {
+		/* custom-baudrate handling */
+		div = sport->port.uartclk / (baud * 16);
+		if (baud == 38400 && quot != div)
+			baud = sport->port.uartclk / (quot * 16);
+
 		div = sport->port.uartclk / (baud * 16);
 		if (div > 7)
 			div = 7;
@@ -1048,7 +1454,7 @@ imx_set_termios(struct uart_port *port, struct ktermios *termios,
 	writel(num, sport->port.membase + UBIR);
 	writel(denom, sport->port.membase + UBMR);
 
-	if (is_imx21_uart(sport))
+	if (!is_imx1_uart(sport))
 		writel(sport->port.uartclk / div / 1000,
 				sport->port.membase + IMX21_ONEMS);
 
@@ -1060,6 +1466,8 @@ imx_set_termios(struct uart_port *port, struct ktermios *termios,
 	if (UART_ENABLE_MS(&sport->port, termios->c_cflag))
 		imx_enable_ms(&sport->port);
 
+	if (sport->dma_is_inited && !sport->dma_is_enabled)
+		imx_enable_dma(sport);
 	spin_unlock_irqrestore(&sport->port.lock, flags);
 }
 
@@ -1251,6 +1659,16 @@ imx_console_write(struct console *co, const char *s, unsigned int count)
 	unsigned int ucr1;
 	unsigned long flags = 0;
 	int locked = 1;
+	int retval;
+
+	retval = clk_enable(sport->clk_per);
+	if (retval)
+		return;
+	retval = clk_enable(sport->clk_ipg);
+	if (retval) {
+		clk_disable(sport->clk_per);
+		return;
+	}
 
 	if (sport->port.sysrq)
 		locked = 0;
@@ -1286,6 +1704,9 @@ imx_console_write(struct console *co, const char *s, unsigned int count)
 
 	if (locked)
 		spin_unlock_irqrestore(&sport->port.lock, flags);
+
+	clk_disable(sport->clk_ipg);
+	clk_disable(sport->clk_per);
 }
 
 /*
@@ -1359,6 +1780,7 @@ imx_console_setup(struct console *co, char *options)
 	int bits = 8;
 	int parity = 'n';
 	int flow = 'n';
+	int retval;
 
 	/*
 	 * Check whether an invalid uart number has been specified, and
@@ -1371,6 +1793,11 @@ imx_console_setup(struct console *co, char *options)
 	if (sport == NULL)
 		return -ENODEV;
 
+	/* For setting the registers, we only need to enable the ipg clock. */
+	retval = clk_prepare_enable(sport->clk_ipg);
+	if (retval)
+		goto error_console;
+
 	if (options)
 		uart_parse_options(options, &baud, &parity, &bits, &flow);
 	else
@@ -1378,7 +1805,20 @@ imx_console_setup(struct console *co, char *options)
 
 	imx_setup_ufcr(sport, 0);
 
-	return uart_set_options(&sport->port, co, baud, parity, bits, flow);
+	retval = uart_set_options(&sport->port, co, baud, parity, bits, flow);
+
+	clk_disable(sport->clk_ipg);
+	if (retval) {
+		clk_unprepare(sport->clk_ipg);
+		goto error_console;
+	}
+
+	retval = clk_prepare(sport->clk_per);
+	if (retval)
+		clk_disable_unprepare(sport->clk_ipg);
+
+error_console:
+	return retval;
 }
 
 static struct uart_driver imx_reg;
@@ -1472,6 +1912,9 @@ static int serial_imx_probe_dt(struct imx_port *sport,
 
 	sport->devdata = of_id->data;
 
+	if (of_device_is_stdout_path(np))
+		add_preferred_console(imx_reg.cons->name, sport->port.line, 0);
+
 	return 0;
 }
 #else
@@ -1485,7 +1928,7 @@ static inline int serial_imx_probe_dt(struct imx_port *sport,
 static void serial_imx_probe_pdata(struct imx_port *sport,
 		struct platform_device *pdev)
 {
-	struct imxuart_platform_data *pdata = pdev->dev.platform_data;
+	struct imxuart_platform_data *pdata = dev_get_platdata(&pdev->dev);
 
 	sport->port.line = pdev->id;
 	sport->devdata = (struct imx_uart_data	*) pdev->id_entry->driver_data;
@@ -1507,7 +1950,6 @@ static int serial_imx_probe(struct platform_device *pdev)
 	void __iomem *base;
 	int ret = 0;
 	struct resource *res;
-	struct pinctrl *pinctrl;
 
 	sport = devm_kzalloc(&pdev->dev, sizeof(*sport), GFP_KERNEL);
 	if (!sport)
@@ -1543,13 +1985,6 @@ static int serial_imx_probe(struct platform_device *pdev)
 	sport->timer.function = imx_timeout;
 	sport->timer.data     = (unsigned long)sport;
 
-	pinctrl = devm_pinctrl_get_select_default(&pdev->dev);
-	if (IS_ERR(pinctrl)) {
-		ret = PTR_ERR(pinctrl);
-		dev_err(&pdev->dev, "failed to get default pinctrl: %d\n", ret);
-		return ret;
-	}
-
 	sport->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
 	if (IS_ERR(sport->clk_ipg)) {
 		ret = PTR_ERR(sport->clk_ipg);
@@ -1564,18 +1999,15 @@ static int serial_imx_probe(struct platform_device *pdev)
 		return ret;
 	}
 
-	clk_prepare_enable(sport->clk_per);
-	clk_prepare_enable(sport->clk_ipg);
-
 	sport->port.uartclk = clk_get_rate(sport->clk_per);
 
 	imx_ports[sport->port.line] = sport;
 
-	pdata = pdev->dev.platform_data;
+	pdata = dev_get_platdata(&pdev->dev);
 	if (pdata && pdata->init) {
 		ret = pdata->init(pdev);
 		if (ret)
-			goto clkput;
+			return ret;
 	}
 
 	ret = uart_add_one_port(&imx_reg, &sport->port);
@@ -1583,18 +2015,10 @@ static int serial_imx_probe(struct platform_device *pdev)
 		goto deinit;
 	platform_set_drvdata(pdev, sport);
 
-	if (!uart_console(&sport->port)) {
-		clk_disable_unprepare(sport->clk_per);
-		clk_disable_unprepare(sport->clk_ipg);
-	}
-
 	return 0;
 deinit:
 	if (pdata && pdata->exit)
 		pdata->exit(pdev);
-clkput:
-	clk_disable_unprepare(sport->clk_per);
-	clk_disable_unprepare(sport->clk_ipg);
 	return ret;
 }
 
@@ -1603,9 +2027,7 @@ static int serial_imx_remove(struct platform_device *pdev)
 	struct imxuart_platform_data *pdata;
 	struct imx_port *sport = platform_get_drvdata(pdev);
 
-	pdata = pdev->dev.platform_data;
-
-	platform_set_drvdata(pdev, NULL);
+	pdata = dev_get_platdata(&pdev->dev);
 
 	uart_remove_one_port(&imx_reg, &sport->port);
 
diff --git a/drivers/tty/serial/ioc4_serial.c b/drivers/tty/serial/ioc4_serial.c
index e2520abcb1c..1274499850f 100644
--- a/drivers/tty/serial/ioc4_serial.c
+++ b/drivers/tty/serial/ioc4_serial.c
@@ -297,7 +297,7 @@ struct ioc4_serial {
 	struct ioc4_uartregs uart_1;
 	struct ioc4_uartregs uart_2;
 	struct ioc4_uartregs uart_3;
-} ioc4_serial;
+};
 
 /* UART clock speed */
 #define IOC4_SER_XIN_CLK_66     66666667
@@ -2767,7 +2767,7 @@ ioc4_serial_core_attach(struct pci_dev *pdev, int port_type)
  *		called per card found from IOC4 master module.
  * @idd: Master module data for this IOC4
  */
-int
+static int
 ioc4_serial_attach_one(struct ioc4_driver_data *idd)
 {
 	unsigned long tmp_addr1;
diff --git a/drivers/tty/serial/lantiq.c b/drivers/tty/serial/lantiq.c
index 15733da757c..88d01e0bb0c 100644
--- a/drivers/tty/serial/lantiq.c
+++ b/drivers/tty/serial/lantiq.c
@@ -318,7 +318,7 @@ lqasc_startup(struct uart_port *port)
 	struct ltq_uart_port *ltq_port = to_ltq_uart_port(port);
 	int retval;
 
-	if (ltq_port->clk)
+	if (!IS_ERR(ltq_port->clk))
 		clk_enable(ltq_port->clk);
 	port->uartclk = clk_get_rate(ltq_port->fpiclk);
 
@@ -386,7 +386,7 @@ lqasc_shutdown(struct uart_port *port)
 		port->membase + LTQ_ASC_RXFCON);
 	ltq_w32_mask(ASCTXFCON_TXFEN, ASCTXFCON_TXFFLU,
 		port->membase + LTQ_ASC_TXFCON);
-	if (ltq_port->clk)
+	if (!IS_ERR(ltq_port->clk))
 		clk_disable(ltq_port->clk);
 }
 
@@ -636,6 +636,9 @@ lqasc_console_setup(struct console *co, char *options)
 
 	port = &ltq_port->port;
 
+	if (!IS_ERR(ltq_port->clk))
+		clk_enable(ltq_port->clk);
+
 	port->uartclk = clk_get_rate(ltq_port->fpiclk);
 
 	if (options)
diff --git a/drivers/tty/serial/lpc32xx_hs.c b/drivers/tty/serial/lpc32xx_hs.c
index dffea6b2cd7..701644f0682 100644
--- a/drivers/tty/serial/lpc32xx_hs.c
+++ b/drivers/tty/serial/lpc32xx_hs.c
@@ -279,7 +279,10 @@ static void __serial_lpc32xx_rx(struct uart_port *port)
 
 		tmp = readl(LPC32XX_HSUART_FIFO(port->membase));
 	}
+
+	spin_unlock(&port->lock);
 	tty_flip_buffer_push(tport);
+	spin_lock(&port->lock);
 }
 
 static void __serial_lpc32xx_tx(struct uart_port *port)
@@ -351,10 +354,8 @@ static irqreturn_t serial_lpc32xx_interrupt(int irq, void *dev_id)
 	}
 
 	/* Data received? */
-	if (status & (LPC32XX_HSU_RX_TIMEOUT_INT | LPC32XX_HSU_RX_TRIG_INT)) {
+	if (status & (LPC32XX_HSU_RX_TIMEOUT_INT | LPC32XX_HSU_RX_TRIG_INT))
 		__serial_lpc32xx_rx(port);
-		tty_flip_buffer_push(tport);
-	}
 
 	/* Transmit data request? */
 	if ((status & LPC32XX_HSU_TX_INT) && (!uart_tx_stopped(port))) {
diff --git a/drivers/tty/serial/m32r_sio.c b/drivers/tty/serial/m32r_sio.c
index bb1afa0922e..9cd9b4eba9f 100644
--- a/drivers/tty/serial/m32r_sio.c
+++ b/drivers/tty/serial/m32r_sio.c
@@ -368,7 +368,10 @@ static void receive_chars(struct uart_sio_port *up, int *status)
 	ignore_char:
 		*status = serial_in(up, UART_LSR);
 	} while ((*status & UART_LSR_DR) && (max_count-- > 0));
+
+	spin_unlock(&up->port.lock);
 	tty_flip_buffer_push(port);
+	spin_lock(&up->port.lock);
 }
 
 static void transmit_chars(struct uart_sio_port *up)
diff --git a/drivers/tty/serial/max3100.c b/drivers/tty/serial/max3100.c
index 35866d5872a..79f9a9eff54 100644
--- a/drivers/tty/serial/max3100.c
+++ b/drivers/tty/serial/max3100.c
@@ -779,7 +779,7 @@ static int max3100_probe(struct spi_device *spi)
 	max3100s[i]->irq = spi->irq;
 	spin_lock_init(&max3100s[i]->conf_lock);
 	spi_set_drvdata(spi, max3100s[i]);
-	pdata = spi->dev.platform_data;
+	pdata = dev_get_platdata(&spi->dev);
 	max3100s[i]->crystal = pdata->crystal;
 	max3100s[i]->loopback = pdata->loopback;
 	max3100s[i]->poll_time = pdata->poll_time * HZ / 1000;
diff --git a/drivers/tty/serial/max310x.c b/drivers/tty/serial/max310x.c
index 8941e641894..b2e707aa603 100644
--- a/drivers/tty/serial/max310x.c
+++ b/drivers/tty/serial/max310x.c
@@ -1,7 +1,7 @@
 /*
- *  Maxim (Dallas) MAX3107/8 serial driver
+ *  Maxim (Dallas) MAX3107/8/9, MAX14830 serial driver
  *
- *  Copyright (C) 2012 Alexander Shiyan <shc_work@mail.ru>
+ *  Copyright (C) 2012-2013 Alexander Shiyan <shc_work@mail.ru>
  *
  *  Based on max3100.c, by Christian Pellegrin <chripell@evolware.org>
  *  Based on max3110.c, by Feng Tang <feng.tang@intel.com>
@@ -13,11 +13,10 @@
  *  (at your option) any later version.
  */
 
-/* TODO: MAX3109 support (Dual) */
-/* TODO: MAX14830 support (Quad) */
-
 #include <linux/module.h>
+#include <linux/delay.h>
 #include <linux/device.h>
+#include <linux/bitops.h>
 #include <linux/serial_core.h>
 #include <linux/serial.h>
 #include <linux/tty.h>
@@ -25,8 +24,10 @@
 #include <linux/regmap.h>
 #include <linux/gpio.h>
 #include <linux/spi/spi.h>
+
 #include <linux/platform_data/max310x.h>
 
+#define MAX310X_NAME			"max310x"
 #define MAX310X_MAJOR			204
 #define MAX310X_MINOR			209
 
@@ -37,7 +38,8 @@
 #define MAX310X_IRQSTS_REG		(0x02) /* IRQ status */
 #define MAX310X_LSR_IRQEN_REG		(0x03) /* LSR IRQ enable */
 #define MAX310X_LSR_IRQSTS_REG		(0x04) /* LSR IRQ status */
-#define MAX310X_SPCHR_IRQEN_REG		(0x05) /* Special char IRQ enable */
+#define MAX310X_REG_05			(0x05)
+#define MAX310X_SPCHR_IRQEN_REG		MAX310X_REG_05 /* Special char IRQ en */
 #define MAX310X_SPCHR_IRQSTS_REG	(0x06) /* Special char IRQ status */
 #define MAX310X_STS_IRQEN_REG		(0x07) /* Status IRQ enable */
 #define MAX310X_STS_IRQSTS_REG		(0x08) /* Status IRQ status */
@@ -63,8 +65,15 @@
 #define MAX310X_BRGDIVLSB_REG		(0x1c) /* Baud rate divisor LSB */
 #define MAX310X_BRGDIVMSB_REG		(0x1d) /* Baud rate divisor MSB */
 #define MAX310X_CLKSRC_REG		(0x1e) /* Clock source */
-/* Only present in MAX3107 */
-#define MAX3107_REVID_REG		(0x1f) /* Revision identification */
+#define MAX310X_REG_1F			(0x1f)
+
+#define MAX310X_REVID_REG		MAX310X_REG_1F /* Revision ID */
+
+#define MAX310X_GLOBALIRQ_REG		MAX310X_REG_1F /* Global IRQ (RO) */
+#define MAX310X_GLOBALCMD_REG		MAX310X_REG_1F /* Global Command (WO) */
+
+/* Extended registers */
+#define MAX310X_REVID_EXTREG		MAX310X_REG_05 /* Revision ID */
 
 /* IRQ register bits */
 #define MAX310X_IRQ_LSR_BIT		(1 << 0) /* LSR interrupt */
@@ -246,58 +255,210 @@
 #define MAX310X_CLKSRC_EXTCLK_BIT	(1 << 4) /* External clock enable */
 #define MAX310X_CLKSRC_CLK2RTS_BIT	(1 << 7) /* Baud clk to RTS pin */
 
+/* Global commands */
+#define MAX310X_EXTREG_ENBL		(0xce)
+#define MAX310X_EXTREG_DSBL		(0xcd)
+
 /* Misc definitions */
 #define MAX310X_FIFO_SIZE		(128)
+#define MAX310x_REV_MASK		(0xfc)
 
 /* MAX3107 specific */
 #define MAX3107_REV_ID			(0xa0)
-#define MAX3107_REV_MASK		(0xfe)
-
-/* IRQ status bits definitions */
-#define MAX310X_IRQ_TX			(MAX310X_IRQ_TXFIFO_BIT | \
-					 MAX310X_IRQ_TXEMPTY_BIT)
-#define MAX310X_IRQ_RX			(MAX310X_IRQ_RXFIFO_BIT | \
-					 MAX310X_IRQ_RXEMPTY_BIT)
-
-/* Supported chip types */
-enum {
-	MAX310X_TYPE_MAX3107	= 3107,
-	MAX310X_TYPE_MAX3108	= 3108,
+
+/* MAX3109 specific */
+#define MAX3109_REV_ID			(0xc0)
+
+/* MAX14830 specific */
+#define MAX14830_BRGCFG_CLKDIS_BIT	(1 << 6) /* Clock Disable */
+#define MAX14830_REV_ID			(0xb0)
+
+struct max310x_devtype {
+	char	name[9];
+	int	nr;
+	int	(*detect)(struct device *);
+	void	(*power)(struct uart_port *, int);
 };
 
-struct max310x_port {
-	struct uart_driver	uart;
+struct max310x_one {
 	struct uart_port	port;
+	struct work_struct	tx_work;
+};
 
-	const char		*name;
-	int			uartclk;
-
-	unsigned int		nr_gpio;
+struct max310x_port {
+	struct uart_driver	uart;
+	struct max310x_devtype	*devtype;
+	struct regmap		*regmap;
+	struct regmap_config	regcfg;
+	struct mutex		mutex;
+	struct max310x_pdata	*pdata;
+	int			gpio_used;
 #ifdef CONFIG_GPIOLIB
 	struct gpio_chip	gpio;
 #endif
+	struct max310x_one	p[0];
+};
 
-	struct regmap		*regmap;
-	struct regmap_config	regcfg;
+static u8 max310x_port_read(struct uart_port *port, u8 reg)
+{
+	struct max310x_port *s = dev_get_drvdata(port->dev);
+	unsigned int val = 0;
 
-	struct workqueue_struct	*wq;
-	struct work_struct	tx_work;
+	regmap_read(s->regmap, port->iobase + reg, &val);
 
-	struct mutex		max310x_mutex;
+	return val;
+}
 
-	struct max310x_pdata	*pdata;
+static void max310x_port_write(struct uart_port *port, u8 reg, u8 val)
+{
+	struct max310x_port *s = dev_get_drvdata(port->dev);
+
+	regmap_write(s->regmap, port->iobase + reg, val);
+}
+
+static void max310x_port_update(struct uart_port *port, u8 reg, u8 mask, u8 val)
+{
+	struct max310x_port *s = dev_get_drvdata(port->dev);
+
+	regmap_update_bits(s->regmap, port->iobase + reg, mask, val);
+}
+
+static int max3107_detect(struct device *dev)
+{
+	struct max310x_port *s = dev_get_drvdata(dev);
+	unsigned int val = 0;
+	int ret;
+
+	ret = regmap_read(s->regmap, MAX310X_REVID_REG, &val);
+	if (ret)
+		return ret;
+
+	if (((val & MAX310x_REV_MASK) != MAX3107_REV_ID)) {
+		dev_err(dev,
+			"%s ID 0x%02x does not match\n", s->devtype->name, val);
+		return -ENODEV;
+	}
+
+	return 0;
+}
+
+static int max3108_detect(struct device *dev)
+{
+	struct max310x_port *s = dev_get_drvdata(dev);
+	unsigned int val = 0;
+	int ret;
+
+	/* MAX3108 have not REV ID register, we just check default value
+	 * from clocksource register to make sure everything works.
+	 */
+	ret = regmap_read(s->regmap, MAX310X_CLKSRC_REG, &val);
+	if (ret)
+		return ret;
+
+	if (val != (MAX310X_CLKSRC_EXTCLK_BIT | MAX310X_CLKSRC_PLLBYP_BIT)) {
+		dev_err(dev, "%s not present\n", s->devtype->name);
+		return -ENODEV;
+	}
+
+	return 0;
+}
+
+static int max3109_detect(struct device *dev)
+{
+	struct max310x_port *s = dev_get_drvdata(dev);
+	unsigned int val = 0;
+	int ret;
+
+	ret = regmap_read(s->regmap, MAX310X_REVID_REG, &val);
+	if (ret)
+		return ret;
+
+	if (((val & MAX310x_REV_MASK) != MAX3109_REV_ID)) {
+		dev_err(dev,
+			"%s ID 0x%02x does not match\n", s->devtype->name, val);
+		return -ENODEV;
+	}
+
+	return 0;
+}
+
+static void max310x_power(struct uart_port *port, int on)
+{
+	max310x_port_update(port, MAX310X_MODE1_REG,
+			    MAX310X_MODE1_FORCESLEEP_BIT,
+			    on ? 0 : MAX310X_MODE1_FORCESLEEP_BIT);
+	if (on)
+		msleep(50);
+}
+
+static int max14830_detect(struct device *dev)
+{
+	struct max310x_port *s = dev_get_drvdata(dev);
+	unsigned int val = 0;
+	int ret;
+
+	ret = regmap_write(s->regmap, MAX310X_GLOBALCMD_REG,
+			   MAX310X_EXTREG_ENBL);
+	if (ret)
+		return ret;
+	
+	regmap_read(s->regmap, MAX310X_REVID_EXTREG, &val);
+	regmap_write(s->regmap, MAX310X_GLOBALCMD_REG, MAX310X_EXTREG_DSBL);
+	if (((val & MAX310x_REV_MASK) != MAX14830_REV_ID)) {
+		dev_err(dev,
+			"%s ID 0x%02x does not match\n", s->devtype->name, val);
+		return -ENODEV;
+	}
+
+	return 0;
+}
+
+static void max14830_power(struct uart_port *port, int on)
+{
+	max310x_port_update(port, MAX310X_BRGCFG_REG,
+			    MAX14830_BRGCFG_CLKDIS_BIT,
+			    on ? 0 : MAX14830_BRGCFG_CLKDIS_BIT);
+	if (on)
+		msleep(50);
+}
+
+static const struct max310x_devtype max3107_devtype = {
+	.name	= "MAX3107",
+	.nr	= 1,
+	.detect	= max3107_detect,
+	.power	= max310x_power,
+};
+
+static const struct max310x_devtype max3108_devtype = {
+	.name	= "MAX3108",
+	.nr	= 1,
+	.detect	= max3108_detect,
+	.power	= max310x_power,
+};
+
+static const struct max310x_devtype max3109_devtype = {
+	.name	= "MAX3109",
+	.nr	= 2,
+	.detect	= max3109_detect,
+	.power	= max310x_power,
+};
+
+static const struct max310x_devtype max14830_devtype = {
+	.name	= "MAX14830",
+	.nr	= 4,
+	.detect	= max14830_detect,
+	.power	= max14830_power,
 };
 
-static bool max3107_8_reg_writeable(struct device *dev, unsigned int reg)
+static bool max310x_reg_writeable(struct device *dev, unsigned int reg)
 {
-	switch (reg) {
+	switch (reg & 0x1f) {
 	case MAX310X_IRQSTS_REG:
 	case MAX310X_LSR_IRQSTS_REG:
 	case MAX310X_SPCHR_IRQSTS_REG:
 	case MAX310X_STS_IRQSTS_REG:
 	case MAX310X_TXFIFOLVL_REG:
 	case MAX310X_RXFIFOLVL_REG:
-	case MAX3107_REVID_REG: /* Only available on MAX3107 */
 		return false;
 	default:
 		break;
@@ -308,7 +469,7 @@ static bool max3107_8_reg_writeable(struct device *dev, unsigned int reg)
 
 static bool max310x_reg_volatile(struct device *dev, unsigned int reg)
 {
-	switch (reg) {
+	switch (reg & 0x1f) {
 	case MAX310X_RHR_REG:
 	case MAX310X_IRQSTS_REG:
 	case MAX310X_LSR_IRQSTS_REG:
@@ -317,6 +478,9 @@ static bool max310x_reg_volatile(struct device *dev, unsigned int reg)
 	case MAX310X_TXFIFOLVL_REG:
 	case MAX310X_RXFIFOLVL_REG:
 	case MAX310X_GPIODATA_REG:
+	case MAX310X_BRGDIVLSB_REG:
+	case MAX310X_REG_05:
+	case MAX310X_REG_1F:
 		return true;
 	default:
 		break;
@@ -327,7 +491,7 @@ static bool max310x_reg_volatile(struct device *dev, unsigned int reg)
 
 static bool max310x_reg_precious(struct device *dev, unsigned int reg)
 {
-	switch (reg) {
+	switch (reg & 0x1f) {
 	case MAX310X_RHR_REG:
 	case MAX310X_IRQSTS_REG:
 	case MAX310X_SPCHR_IRQSTS_REG:
@@ -340,42 +504,25 @@ static bool max310x_reg_precious(struct device *dev, unsigned int reg)
 	return false;
 }
 
-static void max310x_set_baud(struct max310x_port *s, int baud)
+static void max310x_set_baud(struct uart_port *port, int baud)
 {
-	unsigned int mode = 0, div = s->uartclk / baud;
+	unsigned int mode = 0, div = port->uartclk / baud;
 
 	if (!(div / 16)) {
 		/* Mode x2 */
 		mode = MAX310X_BRGCFG_2XMODE_BIT;
-		div = (s->uartclk * 2) / baud;
+		div = (port->uartclk * 2) / baud;
 	}
 
 	if (!(div / 16)) {
 		/* Mode x4 */
 		mode = MAX310X_BRGCFG_4XMODE_BIT;
-		div = (s->uartclk * 4) / baud;
+		div = (port->uartclk * 4) / baud;
 	}
 
-	regmap_write(s->regmap, MAX310X_BRGDIVMSB_REG,
-		     ((div / 16) >> 8) & 0xff);
-	regmap_write(s->regmap, MAX310X_BRGDIVLSB_REG, (div / 16) & 0xff);
-	regmap_write(s->regmap, MAX310X_BRGCFG_REG, (div % 16) | mode);
-}
-
-static void max310x_wait_pll(struct max310x_port *s)
-{
-	int tryes = 1000;
-
-	/* Wait for PLL only if crystal is used */
-	if (!(s->pdata->driver_flags & MAX310X_EXT_CLK)) {
-		unsigned int sts = 0;
-
-		while (tryes--) {
-			regmap_read(s->regmap, MAX310X_STS_IRQSTS_REG, &sts);
-			if (sts & MAX310X_STS_CLKREADY_BIT)
-				break;
-		}
-	}
+	max310x_port_write(port, MAX310X_BRGDIVMSB_REG, (div / 16) >> 8);
+	max310x_port_write(port, MAX310X_BRGDIVLSB_REG, div / 16);
+	max310x_port_write(port, MAX310X_BRGCFG_REG, (div % 16) | mode);
 }
 
 static int max310x_update_best_err(unsigned long f, long *besterr)
@@ -449,49 +596,49 @@ static int max310x_set_ref_clk(struct max310x_port *s)
 
 	regmap_write(s->regmap, MAX310X_CLKSRC_REG, clksrc);
 
-	if (pllcfg)
-		max310x_wait_pll(s);
-
-	dev_dbg(s->port.dev, "Reference clock set to %lu Hz\n", bestfreq);
+	/* Wait for crystal */
+	if (pllcfg && !(s->pdata->driver_flags & MAX310X_EXT_CLK))
+		msleep(10);
 
 	return (int)bestfreq;
 }
 
-static void max310x_handle_rx(struct max310x_port *s, unsigned int rxlen)
+static void max310x_handle_rx(struct uart_port *port, unsigned int rxlen)
 {
-	unsigned int sts = 0, ch = 0, flag;
+	unsigned int sts, ch, flag;
 
-	if (unlikely(rxlen >= MAX310X_FIFO_SIZE)) {
-		dev_warn(s->port.dev, "Possible RX FIFO overrun %d\n", rxlen);
+	if (unlikely(rxlen >= port->fifosize)) {
+		dev_warn_ratelimited(port->dev,
+				     "Port %i: Possible RX FIFO overrun\n",
+				     port->line);
+		port->icount.buf_overrun++;
 		/* Ensure sanity of RX level */
-		rxlen = MAX310X_FIFO_SIZE;
+		rxlen = port->fifosize;
 	}
 
-	dev_dbg(s->port.dev, "RX Len = %u\n", rxlen);
-
 	while (rxlen--) {
-		regmap_read(s->regmap, MAX310X_RHR_REG, &ch);
-		regmap_read(s->regmap, MAX310X_LSR_IRQSTS_REG, &sts);
+		ch = max310x_port_read(port, MAX310X_RHR_REG);
+		sts = max310x_port_read(port, MAX310X_LSR_IRQSTS_REG);
 
 		sts &= MAX310X_LSR_RXPAR_BIT | MAX310X_LSR_FRERR_BIT |
 		       MAX310X_LSR_RXOVR_BIT | MAX310X_LSR_RXBRK_BIT;
 
-		s->port.icount.rx++;
+		port->icount.rx++;
 		flag = TTY_NORMAL;
 
 		if (unlikely(sts)) {
 			if (sts & MAX310X_LSR_RXBRK_BIT) {
-				s->port.icount.brk++;
-				if (uart_handle_break(&s->port))
+				port->icount.brk++;
+				if (uart_handle_break(port))
 					continue;
 			} else if (sts & MAX310X_LSR_RXPAR_BIT)
-				s->port.icount.parity++;
+				port->icount.parity++;
 			else if (sts & MAX310X_LSR_FRERR_BIT)
-				s->port.icount.frame++;
+				port->icount.frame++;
 			else if (sts & MAX310X_LSR_RXOVR_BIT)
-				s->port.icount.overrun++;
+				port->icount.overrun++;
 
-			sts &= s->port.read_status_mask;
+			sts &= port->read_status_mask;
 			if (sts & MAX310X_LSR_RXBRK_BIT)
 				flag = TTY_BREAK;
 			else if (sts & MAX310X_LSR_RXPAR_BIT)
@@ -502,129 +649,129 @@ static void max310x_handle_rx(struct max310x_port *s, unsigned int rxlen)
 				flag = TTY_OVERRUN;
 		}
 
-		if (uart_handle_sysrq_char(s->port, ch))
+		if (uart_handle_sysrq_char(port, ch))
 			continue;
 
-		if (sts & s->port.ignore_status_mask)
+		if (sts & port->ignore_status_mask)
 			continue;
 
-		uart_insert_char(&s->port, sts, MAX310X_LSR_RXOVR_BIT,
-				 ch, flag);
+		uart_insert_char(port, sts, MAX310X_LSR_RXOVR_BIT, ch, flag);
 	}
 
-	tty_flip_buffer_push(&s->port.state->port);
+	tty_flip_buffer_push(&port->state->port);
 }
 
-static void max310x_handle_tx(struct max310x_port *s)
+static void max310x_handle_tx(struct uart_port *port)
 {
-	struct circ_buf *xmit = &s->port.state->xmit;
-	unsigned int txlen = 0, to_send;
+	struct circ_buf *xmit = &port->state->xmit;
+	unsigned int txlen, to_send;
 
-	if (unlikely(s->port.x_char)) {
-		regmap_write(s->regmap, MAX310X_THR_REG, s->port.x_char);
-		s->port.icount.tx++;
-		s->port.x_char = 0;
+	if (unlikely(port->x_char)) {
+		max310x_port_write(port, MAX310X_THR_REG, port->x_char);
+		port->icount.tx++;
+		port->x_char = 0;
 		return;
 	}
 
-	if (uart_circ_empty(xmit) || uart_tx_stopped(&s->port))
+	if (uart_circ_empty(xmit) || uart_tx_stopped(port))
 		return;
 
 	/* Get length of data pending in circular buffer */
 	to_send = uart_circ_chars_pending(xmit);
 	if (likely(to_send)) {
 		/* Limit to size of TX FIFO */
-		regmap_read(s->regmap, MAX310X_TXFIFOLVL_REG, &txlen);
-		txlen = MAX310X_FIFO_SIZE - txlen;
+		txlen = max310x_port_read(port, MAX310X_TXFIFOLVL_REG);
+		txlen = port->fifosize - txlen;
 		to_send = (to_send > txlen) ? txlen : to_send;
 
-		dev_dbg(s->port.dev, "TX Len = %u\n", to_send);
-
 		/* Add data to send */
-		s->port.icount.tx += to_send;
+		port->icount.tx += to_send;
 		while (to_send--) {
-			regmap_write(s->regmap, MAX310X_THR_REG,
-				     xmit->buf[xmit->tail]);
+			max310x_port_write(port, MAX310X_THR_REG,
+					   xmit->buf[xmit->tail]);
 			xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 		};
 	}
 
 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
-		uart_write_wakeup(&s->port);
+		uart_write_wakeup(port);
 }
 
-static irqreturn_t max310x_ist(int irq, void *dev_id)
+static void max310x_port_irq(struct max310x_port *s, int portno)
 {
-	struct max310x_port *s = (struct max310x_port *)dev_id;
-	unsigned int ists = 0, lsr = 0, rxlen = 0;
+	struct uart_port *port = &s->p[portno].port;
 
-	mutex_lock(&s->max310x_mutex);
+	do {
+		unsigned int ists, lsr, rxlen;
 
-	for (;;) {
 		/* Read IRQ status & RX FIFO level */
-		regmap_read(s->regmap, MAX310X_IRQSTS_REG, &ists);
-		regmap_read(s->regmap, MAX310X_LSR_IRQSTS_REG, &lsr);
-		regmap_read(s->regmap, MAX310X_RXFIFOLVL_REG, &rxlen);
-		if (!ists && !(lsr & MAX310X_LSR_RXTO_BIT) && !rxlen)
+		ists = max310x_port_read(port, MAX310X_IRQSTS_REG);
+		rxlen = max310x_port_read(port, MAX310X_RXFIFOLVL_REG);
+		if (!ists && !rxlen)
 			break;
 
-		dev_dbg(s->port.dev, "IRQ status: 0x%02x\n", ists);
-
-		if (rxlen)
-			max310x_handle_rx(s, rxlen);
-		if (ists & MAX310X_IRQ_TX)
-			max310x_handle_tx(s);
-		if (ists & MAX310X_IRQ_CTS_BIT)
-			uart_handle_cts_change(&s->port,
+		if (ists & MAX310X_IRQ_CTS_BIT) {
+			lsr = max310x_port_read(port, MAX310X_LSR_IRQSTS_REG);
+			uart_handle_cts_change(port,
 					       !!(lsr & MAX310X_LSR_CTS_BIT));
-	}
+		}
+		if (rxlen)
+			max310x_handle_rx(port, rxlen);
+		if (ists & MAX310X_IRQ_TXEMPTY_BIT) {
+			mutex_lock(&s->mutex);
+			max310x_handle_tx(port);
+			mutex_unlock(&s->mutex);
+		}
+	} while (1);
+}
+
+static irqreturn_t max310x_ist(int irq, void *dev_id)
+{
+	struct max310x_port *s = (struct max310x_port *)dev_id;
 
-	mutex_unlock(&s->max310x_mutex);
+	if (s->uart.nr > 1) {
+		do {
+			unsigned int val = ~0;
+
+			WARN_ON_ONCE(regmap_read(s->regmap,
+						 MAX310X_GLOBALIRQ_REG, &val));
+			val = ((1 << s->uart.nr) - 1) & ~val;
+			if (!val)
+				break;
+			max310x_port_irq(s, fls(val) - 1);
+		} while (1);
+	} else
+		max310x_port_irq(s, 0);
 
 	return IRQ_HANDLED;
 }
 
 static void max310x_wq_proc(struct work_struct *ws)
 {
-	struct max310x_port *s = container_of(ws, struct max310x_port, tx_work);
+	struct max310x_one *one = container_of(ws, struct max310x_one, tx_work);
+	struct max310x_port *s = dev_get_drvdata(one->port.dev);
 
-	mutex_lock(&s->max310x_mutex);
-	max310x_handle_tx(s);
-	mutex_unlock(&s->max310x_mutex);
+	mutex_lock(&s->mutex);
+	max310x_handle_tx(&one->port);
+	mutex_unlock(&s->mutex);
 }
 
 static void max310x_start_tx(struct uart_port *port)
 {
-	struct max310x_port *s = container_of(port, struct max310x_port, port);
-
-	queue_work(s->wq, &s->tx_work);
-}
-
-static void max310x_stop_tx(struct uart_port *port)
-{
-	/* Do nothing */
-}
+	struct max310x_one *one = container_of(port, struct max310x_one, port);
 
-static void max310x_stop_rx(struct uart_port *port)
-{
-	/* Do nothing */
+	if (!work_pending(&one->tx_work))
+		schedule_work(&one->tx_work);
 }
 
 static unsigned int max310x_tx_empty(struct uart_port *port)
 {
-	unsigned int val = 0;
-	struct max310x_port *s = container_of(port, struct max310x_port, port);
+	unsigned int lvl, sts;
 
-	mutex_lock(&s->max310x_mutex);
-	regmap_read(s->regmap, MAX310X_TXFIFOLVL_REG, &val);
-	mutex_unlock(&s->max310x_mutex);
+	lvl = max310x_port_read(port, MAX310X_TXFIFOLVL_REG);
+	sts = max310x_port_read(port, MAX310X_IRQSTS_REG);
 
-	return val ? 0 : TIOCSER_TEMT;
-}
-
-static void max310x_enable_ms(struct uart_port *port)
-{
-	/* Modem status not supported */
+	return ((sts & MAX310X_IRQ_TXEMPTY_BIT) && !lvl) ? TIOCSER_TEMT : 0;
 }
 
 static unsigned int max310x_get_mctrl(struct uart_port *port)
@@ -644,28 +791,20 @@ static void max310x_set_mctrl(struct uart_port *port, unsigned int mctrl)
 
 static void max310x_break_ctl(struct uart_port *port, int break_state)
 {
-	struct max310x_port *s = container_of(port, struct max310x_port, port);
-
-	mutex_lock(&s->max310x_mutex);
-	regmap_update_bits(s->regmap, MAX310X_LCR_REG,
-			   MAX310X_LCR_TXBREAK_BIT,
-			   break_state ? MAX310X_LCR_TXBREAK_BIT : 0);
-	mutex_unlock(&s->max310x_mutex);
+	max310x_port_update(port, MAX310X_LCR_REG,
+			    MAX310X_LCR_TXBREAK_BIT,
+			    break_state ? MAX310X_LCR_TXBREAK_BIT : 0);
 }
 
 static void max310x_set_termios(struct uart_port *port,
 				struct ktermios *termios,
 				struct ktermios *old)
 {
-	struct max310x_port *s = container_of(port, struct max310x_port, port);
 	unsigned int lcr, flow = 0;
 	int baud;
 
-	mutex_lock(&s->max310x_mutex);
-
 	/* Mask termios capabilities we don't support */
 	termios->c_cflag &= ~CMSPAR;
-	termios->c_iflag &= ~IXANY;
 
 	/* Word size */
 	switch (termios->c_cflag & CSIZE) {
@@ -696,7 +835,7 @@ static void max310x_set_termios(struct uart_port *port,
 		lcr |= MAX310X_LCR_STOPLEN_BIT; /* 2 stops */
 
 	/* Update LCR register */
-	regmap_write(s->regmap, MAX310X_LCR_REG, lcr);
+	max310x_port_write(port, MAX310X_LCR_REG, lcr);
 
 	/* Set read status mask */
 	port->read_status_mask = MAX310X_LSR_RXOVR_BIT;
@@ -717,8 +856,8 @@ static void max310x_set_termios(struct uart_port *port,
 					    MAX310X_LSR_RXBRK_BIT;
 
 	/* Configure flow control */
-	regmap_write(s->regmap, MAX310X_XON1_REG, termios->c_cc[VSTART]);
-	regmap_write(s->regmap, MAX310X_XOFF1_REG, termios->c_cc[VSTOP]);
+	max310x_port_write(port, MAX310X_XON1_REG, termios->c_cc[VSTART]);
+	max310x_port_write(port, MAX310X_XOFF1_REG, termios->c_cc[VSTOP]);
 	if (termios->c_cflag & CRTSCTS)
 		flow |= MAX310X_FLOWCTRL_AUTOCTS_BIT |
 			MAX310X_FLOWCTRL_AUTORTS_BIT;
@@ -728,7 +867,7 @@ static void max310x_set_termios(struct uart_port *port,
 	if (termios->c_iflag & IXOFF)
 		flow |= MAX310X_FLOWCTRL_SWFLOW1_BIT |
 			MAX310X_FLOWCTRL_SWFLOWEN_BIT;
-	regmap_write(s->regmap, MAX310X_FLOWCTRL_REG, flow);
+	max310x_port_write(port, MAX310X_FLOWCTRL_REG, flow);
 
 	/* Get baud rate generator configuration */
 	baud = uart_get_baud_rate(port, termios, old,
@@ -736,36 +875,30 @@ static void max310x_set_termios(struct uart_port *port,
 				  port->uartclk / 4);
 
 	/* Setup baudrate generator */
-	max310x_set_baud(s, baud);
+	max310x_set_baud(port, baud);
 
 	/* Update timeout according to new baud rate */
 	uart_update_timeout(port, termios->c_cflag, baud);
-
-	mutex_unlock(&s->max310x_mutex);
 }
 
 static int max310x_startup(struct uart_port *port)
 {
 	unsigned int val, line = port->line;
-	struct max310x_port *s = container_of(port, struct max310x_port, port);
-
-	if (s->pdata->suspend)
-		s->pdata->suspend(0);
+	struct max310x_port *s = dev_get_drvdata(port->dev);
 
-	mutex_lock(&s->max310x_mutex);
+	s->devtype->power(port, 1);
 
 	/* Configure baud rate, 9600 as default */
-	max310x_set_baud(s, 9600);
+	max310x_set_baud(port, 9600);
 
 	/* Configure LCR register, 8N1 mode by default */
-	val = MAX310X_LCR_WORD_LEN_8;
-	regmap_write(s->regmap, MAX310X_LCR_REG, val);
+	max310x_port_write(port, MAX310X_LCR_REG, MAX310X_LCR_WORD_LEN_8);
 
 	/* Configure MODE1 register */
-	regmap_update_bits(s->regmap, MAX310X_MODE1_REG,
-			   MAX310X_MODE1_TRNSCVCTRL_BIT,
-			   (s->pdata->uart_flags[line] & MAX310X_AUTO_DIR_CTRL)
-			   ? MAX310X_MODE1_TRNSCVCTRL_BIT : 0);
+	max310x_port_update(port, MAX310X_MODE1_REG,
+			    MAX310X_MODE1_TRNSCVCTRL_BIT,
+			    (s->pdata->uart_flags[line] & MAX310X_AUTO_DIR_CTRL)
+			    ? MAX310X_MODE1_TRNSCVCTRL_BIT : 0);
 
 	/* Configure MODE2 register */
 	val = MAX310X_MODE2_RXEMPTINV_BIT;
@@ -776,63 +909,40 @@ static int max310x_startup(struct uart_port *port)
 
 	/* Reset FIFOs */
 	val |= MAX310X_MODE2_FIFORST_BIT;
-	regmap_write(s->regmap, MAX310X_MODE2_REG, val);
-
-	/* Configure FIFO trigger level register */
-	/* RX FIFO trigger for 16 words, TX FIFO trigger for 64 words */
-	val = MAX310X_FIFOTRIGLVL_RX(16) | MAX310X_FIFOTRIGLVL_TX(64);
-	regmap_write(s->regmap, MAX310X_FIFOTRIGLVL_REG, val);
+	max310x_port_write(port, MAX310X_MODE2_REG, val);
+	max310x_port_update(port, MAX310X_MODE2_REG,
+			    MAX310X_MODE2_FIFORST_BIT, 0);
 
 	/* Configure flow control levels */
 	/* Flow control halt level 96, resume level 48 */
-	val = MAX310X_FLOWLVL_RES(48) | MAX310X_FLOWLVL_HALT(96);
-	regmap_write(s->regmap, MAX310X_FLOWLVL_REG, val);
-
-	/* Clear timeout register */
-	regmap_write(s->regmap, MAX310X_RXTO_REG, 0);
+	max310x_port_write(port, MAX310X_FLOWLVL_REG,
+			   MAX310X_FLOWLVL_RES(48) | MAX310X_FLOWLVL_HALT(96));
 
-	/* Configure LSR interrupt enable register */
-	/* Enable RX timeout interrupt */
-	val = MAX310X_LSR_RXTO_BIT;
-	regmap_write(s->regmap, MAX310X_LSR_IRQEN_REG, val);
+	/* Clear IRQ status register */
+	max310x_port_read(port, MAX310X_IRQSTS_REG);
 
-	/* Clear FIFO reset */
-	regmap_update_bits(s->regmap, MAX310X_MODE2_REG,
-			   MAX310X_MODE2_FIFORST_BIT, 0);
-
-	/* Clear IRQ status register by reading it */
-	regmap_read(s->regmap, MAX310X_IRQSTS_REG, &val);
-
-	/* Configure interrupt enable register */
-	/* Enable CTS change interrupt */
-	val = MAX310X_IRQ_CTS_BIT;
-	/* Enable RX, TX interrupts */
-	val |= MAX310X_IRQ_RX | MAX310X_IRQ_TX;
-	regmap_write(s->regmap, MAX310X_IRQEN_REG, val);
-
-	mutex_unlock(&s->max310x_mutex);
+	/* Enable RX, TX, CTS change interrupts */
+	val = MAX310X_IRQ_RXEMPTY_BIT | MAX310X_IRQ_TXEMPTY_BIT;
+	max310x_port_write(port, MAX310X_IRQEN_REG, val | MAX310X_IRQ_CTS_BIT);
 
 	return 0;
 }
 
 static void max310x_shutdown(struct uart_port *port)
 {
-	struct max310x_port *s = container_of(port, struct max310x_port, port);
+	struct max310x_port *s = dev_get_drvdata(port->dev);
 
 	/* Disable all interrupts */
-	mutex_lock(&s->max310x_mutex);
-	regmap_write(s->regmap, MAX310X_IRQEN_REG, 0);
-	mutex_unlock(&s->max310x_mutex);
+	max310x_port_write(port, MAX310X_IRQEN_REG, 0);
 
-	if (s->pdata->suspend)
-		s->pdata->suspend(1);
+	s->devtype->power(port, 0);
 }
 
 static const char *max310x_type(struct uart_port *port)
 {
-	struct max310x_port *s = container_of(port, struct max310x_port, port);
+	struct max310x_port *s = dev_get_drvdata(port->dev);
 
-	return (port->type == PORT_MAX310X) ? s->name : NULL;
+	return (port->type == PORT_MAX310X) ? s->devtype->name : NULL;
 }
 
 static int max310x_request_port(struct uart_port *port)
@@ -841,134 +951,99 @@ static int max310x_request_port(struct uart_port *port)
 	return 0;
 }
 
-static void max310x_release_port(struct uart_port *port)
-{
-	/* Do nothing */
-}
-
 static void max310x_config_port(struct uart_port *port, int flags)
 {
 	if (flags & UART_CONFIG_TYPE)
 		port->type = PORT_MAX310X;
 }
 
-static int max310x_verify_port(struct uart_port *port, struct serial_struct *ser)
+static int max310x_verify_port(struct uart_port *port, struct serial_struct *s)
 {
-	if ((ser->type == PORT_UNKNOWN) || (ser->type == PORT_MAX310X))
-		return 0;
-	if (ser->irq == port->irq)
-		return 0;
+	if ((s->type != PORT_UNKNOWN) && (s->type != PORT_MAX310X))
+		return -EINVAL;
+	if (s->irq != port->irq)
+		return -EINVAL;
 
-	return -EINVAL;
+	return 0;
 }
 
-static struct uart_ops max310x_ops = {
+static void max310x_null_void(struct uart_port *port)
+{
+	/* Do nothing */
+}
+
+static const struct uart_ops max310x_ops = {
 	.tx_empty	= max310x_tx_empty,
 	.set_mctrl	= max310x_set_mctrl,
 	.get_mctrl	= max310x_get_mctrl,
-	.stop_tx	= max310x_stop_tx,
+	.stop_tx	= max310x_null_void,
 	.start_tx	= max310x_start_tx,
-	.stop_rx	= max310x_stop_rx,
-	.enable_ms	= max310x_enable_ms,
+	.stop_rx	= max310x_null_void,
+	.enable_ms	= max310x_null_void,
 	.break_ctl	= max310x_break_ctl,
 	.startup	= max310x_startup,
 	.shutdown	= max310x_shutdown,
 	.set_termios	= max310x_set_termios,
 	.type		= max310x_type,
 	.request_port	= max310x_request_port,
-	.release_port	= max310x_release_port,
+	.release_port	= max310x_null_void,
 	.config_port	= max310x_config_port,
 	.verify_port	= max310x_verify_port,
 };
 
-#ifdef CONFIG_PM_SLEEP
-
-static int max310x_suspend(struct device *dev)
+static int __maybe_unused max310x_suspend(struct device *dev)
 {
-	int ret;
 	struct max310x_port *s = dev_get_drvdata(dev);
+	int i;
 
-	dev_dbg(dev, "Suspend\n");
-
-	ret = uart_suspend_port(&s->uart, &s->port);
-
-	mutex_lock(&s->max310x_mutex);
-
-	/* Enable sleep mode */
-	regmap_update_bits(s->regmap, MAX310X_MODE1_REG,
-			   MAX310X_MODE1_FORCESLEEP_BIT,
-			   MAX310X_MODE1_FORCESLEEP_BIT);
-
-	mutex_unlock(&s->max310x_mutex);
-
-	if (s->pdata->suspend)
-		s->pdata->suspend(1);
+	for (i = 0; i < s->uart.nr; i++) {
+		uart_suspend_port(&s->uart, &s->p[i].port);
+		s->devtype->power(&s->p[i].port, 0);
+	}
 
-	return ret;
+	return 0;
 }
 
-static int max310x_resume(struct device *dev)
+static int __maybe_unused max310x_resume(struct device *dev)
 {
 	struct max310x_port *s = dev_get_drvdata(dev);
+	int i;
 
-	dev_dbg(dev, "Resume\n");
-
-	if (s->pdata->suspend)
-		s->pdata->suspend(0);
-
-	mutex_lock(&s->max310x_mutex);
-
-	/* Disable sleep mode */
-	regmap_update_bits(s->regmap, MAX310X_MODE1_REG,
-			   MAX310X_MODE1_FORCESLEEP_BIT,
-			   0);
-
-	max310x_wait_pll(s);
-
-	mutex_unlock(&s->max310x_mutex);
+	for (i = 0; i < s->uart.nr; i++) {
+		s->devtype->power(&s->p[i].port, 1);
+		uart_resume_port(&s->uart, &s->p[i].port);
+	}
 
-	return uart_resume_port(&s->uart, &s->port);
+	return 0;
 }
 
-static SIMPLE_DEV_PM_OPS(max310x_pm_ops, max310x_suspend, max310x_resume);
-#define MAX310X_PM_OPS (&max310x_pm_ops)
-
-#else
-#define MAX310X_PM_OPS NULL
-#endif
-
 #ifdef CONFIG_GPIOLIB
 static int max310x_gpio_get(struct gpio_chip *chip, unsigned offset)
 {
-	unsigned int val = 0;
+	unsigned int val;
 	struct max310x_port *s = container_of(chip, struct max310x_port, gpio);
+	struct uart_port *port = &s->p[offset / 4].port;
 
-	mutex_lock(&s->max310x_mutex);
-	regmap_read(s->regmap, MAX310X_GPIODATA_REG, &val);
-	mutex_unlock(&s->max310x_mutex);
+	val = max310x_port_read(port, MAX310X_GPIODATA_REG);
 
-	return !!((val >> 4) & (1 << offset));
+	return !!((val >> 4) & (1 << (offset % 4)));
 }
 
 static void max310x_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
 {
 	struct max310x_port *s = container_of(chip, struct max310x_port, gpio);
+	struct uart_port *port = &s->p[offset / 4].port;
 
-	mutex_lock(&s->max310x_mutex);
-	regmap_update_bits(s->regmap, MAX310X_GPIODATA_REG, 1 << offset, value ?
-							    1 << offset : 0);
-	mutex_unlock(&s->max310x_mutex);
+	max310x_port_update(port, MAX310X_GPIODATA_REG, 1 << (offset % 4),
+			    value ? 1 << (offset % 4) : 0);
 }
 
 static int max310x_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
 {
 	struct max310x_port *s = container_of(chip, struct max310x_port, gpio);
+	struct uart_port *port = &s->p[offset / 4].port;
 
-	mutex_lock(&s->max310x_mutex);
-
-	regmap_update_bits(s->regmap, MAX310X_GPIOCFG_REG, 1 << offset, 0);
-
-	mutex_unlock(&s->max310x_mutex);
+	max310x_port_update(port, MAX310X_GPIOCFG_REG, 1 << (offset % 4), 0);
 
 	return 0;
 }
@@ -977,74 +1052,42 @@ static int max310x_gpio_direction_output(struct gpio_chip *chip,
 					 unsigned offset, int value)
 {
 	struct max310x_port *s = container_of(chip, struct max310x_port, gpio);
+	struct uart_port *port = &s->p[offset / 4].port;
 
-	mutex_lock(&s->max310x_mutex);
-
-	regmap_update_bits(s->regmap, MAX310X_GPIOCFG_REG, 1 << offset,
-							   1 << offset);
-	regmap_update_bits(s->regmap, MAX310X_GPIODATA_REG, 1 << offset, value ?
-							    1 << offset : 0);
-
-	mutex_unlock(&s->max310x_mutex);
+	max310x_port_update(port, MAX310X_GPIODATA_REG, 1 << (offset % 4),
+			    value ? 1 << (offset % 4) : 0);
+	max310x_port_update(port, MAX310X_GPIOCFG_REG, 1 << (offset % 4),
+			    1 << (offset % 4));
 
 	return 0;
 }
 #endif
 
-/* Generic platform data */
-static struct max310x_pdata generic_plat_data = {
-	.driver_flags	= MAX310X_EXT_CLK,
-	.uart_flags[0]	= MAX310X_ECHO_SUPRESS,
-	.frequency	= 26000000,
-};
-
-static int max310x_probe(struct spi_device *spi)
+static int max310x_probe(struct device *dev, int is_spi,
+			 struct max310x_devtype *devtype, int irq)
 {
 	struct max310x_port *s;
-	struct device *dev = &spi->dev;
-	int chiptype = spi_get_device_id(spi)->driver_data;
-	struct max310x_pdata *pdata = dev->platform_data;
-	unsigned int val = 0;
-	int ret;
+	struct max310x_pdata *pdata = dev_get_platdata(dev);
+	int i, ret, uartclk;
 
 	/* Check for IRQ */
-	if (spi->irq <= 0) {
+	if (irq <= 0) {
 		dev_err(dev, "No IRQ specified\n");
 		return -ENOTSUPP;
 	}
 
+	if (!pdata) {
+		dev_err(dev, "No platform data supplied\n");
+		return -EINVAL;
+	}
+
 	/* Alloc port structure */
-	s = devm_kzalloc(dev, sizeof(struct max310x_port), GFP_KERNEL);
+	s = devm_kzalloc(dev, sizeof(*s) +
+			 sizeof(struct max310x_one) * devtype->nr, GFP_KERNEL);
 	if (!s) {
 		dev_err(dev, "Error allocating port structure\n");
 		return -ENOMEM;
 	}
-	dev_set_drvdata(dev, s);
-
-	if (!pdata) {
-		dev_warn(dev, "No platform data supplied, using defaults\n");
-		pdata = &generic_plat_data;
-	}
-	s->pdata = pdata;
-
-	/* Individual chip settings */
-	switch (chiptype) {
-	case MAX310X_TYPE_MAX3107:
-		s->name = "MAX3107";
-		s->nr_gpio = 4;
-		s->uart.nr = 1;
-		s->regcfg.max_register = 0x1f;
-		break;
-	case MAX310X_TYPE_MAX3108:
-		s->name = "MAX3108";
-		s->nr_gpio = 4;
-		s->uart.nr = 1;
-		s->regcfg.max_register = 0x1e;
-		break;
-	default:
-		dev_err(dev, "Unsupported chip type %i\n", chiptype);
-		return -ENOTSUPP;
-	}
 
 	/* Check input frequency */
 	if ((pdata->driver_flags & MAX310X_EXT_CLK) &&
@@ -1055,13 +1098,11 @@ static int max310x_probe(struct spi_device *spi)
 	   ((pdata->frequency < 1000000) || (pdata->frequency > 4000000)))
 		goto err_freq;
 
-	mutex_init(&s->max310x_mutex);
+	s->pdata = pdata;
+	s->devtype = devtype;
+	dev_set_drvdata(dev, s);
 
-	/* Setup SPI bus */
-	spi->mode		= SPI_MODE_0;
-	spi->bits_per_word	= 8;
-	spi->max_speed_hz	= 26000000;
-	spi_setup(spi);
+	mutex_init(&s->mutex);
 
 	/* Setup regmap */
 	s->regcfg.reg_bits		= 8;
@@ -1069,109 +1110,100 @@ static int max310x_probe(struct spi_device *spi)
 	s->regcfg.read_flag_mask	= 0x00;
 	s->regcfg.write_flag_mask	= 0x80;
 	s->regcfg.cache_type		= REGCACHE_RBTREE;
-	s->regcfg.writeable_reg		= max3107_8_reg_writeable;
+	s->regcfg.writeable_reg		= max310x_reg_writeable;
 	s->regcfg.volatile_reg		= max310x_reg_volatile;
 	s->regcfg.precious_reg		= max310x_reg_precious;
-	s->regmap = devm_regmap_init_spi(spi, &s->regcfg);
+	s->regcfg.max_register		= devtype->nr * 0x20 - 1;
+
+	if (IS_ENABLED(CONFIG_SPI_MASTER) && is_spi) {
+		struct spi_device *spi = to_spi_device(dev);
+
+		s->regmap = devm_regmap_init_spi(spi, &s->regcfg);
+	} else
+		return -ENOTSUPP;
+
 	if (IS_ERR(s->regmap)) {
-		ret = PTR_ERR(s->regmap);
 		dev_err(dev, "Failed to initialize register map\n");
-		goto err_out;
-	}
-
-	/* Reset chip & check SPI function */
-	ret = regmap_write(s->regmap, MAX310X_MODE2_REG, MAX310X_MODE2_RST_BIT);
-	if (ret) {
-		dev_err(dev, "SPI transfer failed\n");
-		goto err_out;
-	}
-	/* Clear chip reset */
-	regmap_write(s->regmap, MAX310X_MODE2_REG, 0);
-
-	switch (chiptype) {
-	case MAX310X_TYPE_MAX3107:
-		/* Check REV ID to ensure we are talking to what we expect */
-		regmap_read(s->regmap, MAX3107_REVID_REG, &val);
-		if (((val & MAX3107_REV_MASK) != MAX3107_REV_ID)) {
-			dev_err(dev, "%s ID 0x%02x does not match\n",
-				s->name, val);
-			ret = -ENODEV;
-			goto err_out;
-		}
-		break;
-	case MAX310X_TYPE_MAX3108:
-		/* MAX3108 have not REV ID register, we just check default value
-		 * from clocksource register to make sure everything works.
-		 */
-		regmap_read(s->regmap, MAX310X_CLKSRC_REG, &val);
-		if (val != (MAX310X_CLKSRC_EXTCLK_BIT |
-			    MAX310X_CLKSRC_PLLBYP_BIT)) {
-			dev_err(dev, "%s not present\n", s->name);
-			ret = -ENODEV;
-			goto err_out;
-		}
-		break;
+		return PTR_ERR(s->regmap);
 	}
 
 	/* Board specific configure */
-	if (pdata->init)
-		pdata->init();
-	if (pdata->suspend)
-		pdata->suspend(0);
-
-	/* Calculate referecne clock */
-	s->uartclk = max310x_set_ref_clk(s);
-
-	/* Disable all interrupts */
-	regmap_write(s->regmap, MAX310X_IRQEN_REG, 0);
-
-	/* Setup MODE1 register */
-	val = MAX310X_MODE1_IRQSEL_BIT; /* Enable IRQ pin */
-	if (pdata->driver_flags & MAX310X_AUTOSLEEP)
-		val = MAX310X_MODE1_AUTOSLEEP_BIT;
-	regmap_write(s->regmap, MAX310X_MODE1_REG, val);
-
-	/* Setup interrupt */
-	ret = devm_request_threaded_irq(dev, spi->irq, NULL, max310x_ist,
-					IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
-					dev_name(dev), s);
-	if (ret) {
-		dev_err(dev, "Unable to reguest IRQ %i\n", spi->irq);
-		goto err_out;
+	if (s->pdata->init)
+		s->pdata->init();
+
+	/* Check device to ensure we are talking to what we expect */
+	ret = devtype->detect(dev);
+	if (ret)
+		return ret;
+
+	for (i = 0; i < devtype->nr; i++) {
+		unsigned int offs = i << 5;
+
+		/* Reset port */
+		regmap_write(s->regmap, MAX310X_MODE2_REG + offs,
+			     MAX310X_MODE2_RST_BIT);
+		/* Clear port reset */
+		regmap_write(s->regmap, MAX310X_MODE2_REG + offs, 0);
+
+		/* Wait for port startup */
+		do {
+			regmap_read(s->regmap,
+				    MAX310X_BRGDIVLSB_REG + offs, &ret);
+		} while (ret != 0x01);
+
+		regmap_update_bits(s->regmap, MAX310X_MODE1_REG + offs,
+				   MAX310X_MODE1_AUTOSLEEP_BIT,
+				   MAX310X_MODE1_AUTOSLEEP_BIT);
 	}
 
+	uartclk = max310x_set_ref_clk(s);
+	dev_dbg(dev, "Reference clock set to %i Hz\n", uartclk);
+
 	/* Register UART driver */
 	s->uart.owner		= THIS_MODULE;
-	s->uart.driver_name	= dev_name(dev);
 	s->uart.dev_name	= "ttyMAX";
 	s->uart.major		= MAX310X_MAJOR;
 	s->uart.minor		= MAX310X_MINOR;
+	s->uart.nr		= devtype->nr;
 	ret = uart_register_driver(&s->uart);
 	if (ret) {
 		dev_err(dev, "Registering UART driver failed\n");
-		goto err_out;
+		return ret;
 	}
 
-	/* Initialize workqueue for start TX */
-	s->wq = create_freezable_workqueue(dev_name(dev));
-	INIT_WORK(&s->tx_work, max310x_wq_proc);
-
-	/* Initialize UART port data */
-	s->port.line		= 0;
-	s->port.dev		= dev;
-	s->port.irq		= spi->irq;
-	s->port.type		= PORT_MAX310X;
-	s->port.fifosize	= MAX310X_FIFO_SIZE;
-	s->port.flags		= UPF_SKIP_TEST | UPF_FIXED_TYPE;
-	s->port.iotype		= UPIO_PORT;
-	s->port.membase		= (void __iomem *)0xffffffff; /* Bogus value */
-	s->port.uartclk		= s->uartclk;
-	s->port.ops		= &max310x_ops;
-	uart_add_one_port(&s->uart, &s->port);
+	for (i = 0; i < devtype->nr; i++) {
+		/* Initialize port data */
+		s->p[i].port.line	= i;
+		s->p[i].port.dev	= dev;
+		s->p[i].port.irq	= irq;
+		s->p[i].port.type	= PORT_MAX310X;
+		s->p[i].port.fifosize	= MAX310X_FIFO_SIZE;
+		s->p[i].port.flags	= UPF_SKIP_TEST | UPF_FIXED_TYPE |
+					  UPF_LOW_LATENCY;
+		s->p[i].port.iotype	= UPIO_PORT;
+		s->p[i].port.iobase	= i * 0x20;
+		s->p[i].port.membase	= (void __iomem *)~0;
+		s->p[i].port.uartclk	= uartclk;
+		s->p[i].port.ops	= &max310x_ops;
+		/* Disable all interrupts */
+		max310x_port_write(&s->p[i].port, MAX310X_IRQEN_REG, 0);
+		/* Clear IRQ status register */
+		max310x_port_read(&s->p[i].port, MAX310X_IRQSTS_REG);
+		/* Enable IRQ pin */
+		max310x_port_update(&s->p[i].port, MAX310X_MODE1_REG,
+				    MAX310X_MODE1_IRQSEL_BIT,
+				    MAX310X_MODE1_IRQSEL_BIT);
+		/* Initialize queue for start TX */
+		INIT_WORK(&s->p[i].tx_work, max310x_wq_proc);
+		/* Register port */
+		uart_add_one_port(&s->uart, &s->p[i].port);
+		/* Go to suspend mode */
+		devtype->power(&s->p[i].port, 0);
+	}
 
 #ifdef CONFIG_GPIOLIB
 	/* Setup GPIO cotroller */
-	if (pdata->gpio_base) {
+	if (s->pdata->gpio_base) {
 		s->gpio.owner		= THIS_MODULE;
 		s->gpio.dev		= dev;
 		s->gpio.label		= dev_name(dev);
@@ -1179,86 +1211,107 @@ static int max310x_probe(struct spi_device *spi)
 		s->gpio.get		= max310x_gpio_get;
 		s->gpio.direction_output= max310x_gpio_direction_output;
 		s->gpio.set		= max310x_gpio_set;
-		s->gpio.base		= pdata->gpio_base;
-		s->gpio.ngpio		= s->nr_gpio;
+		s->gpio.base		= s->pdata->gpio_base;
+		s->gpio.ngpio		= devtype->nr * 4;
 		s->gpio.can_sleep	= 1;
-		if (gpiochip_add(&s->gpio)) {
-			/* Indicate that we should not call gpiochip_remove */
-			s->gpio.base = 0;
-		}
+		if (!gpiochip_add(&s->gpio))
+			s->gpio_used = 1;
 	} else
 		dev_info(dev, "GPIO support not enabled\n");
 #endif
 
-	/* Go to suspend mode */
-	if (pdata->suspend)
-		pdata->suspend(1);
+	/* Setup interrupt */
+	ret = devm_request_threaded_irq(dev, irq, NULL, max310x_ist,
+					IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
+					dev_name(dev), s);
+	if (ret) {
+		dev_err(dev, "Unable to reguest IRQ %i\n", irq);
+#ifdef CONFIG_GPIOLIB
+		if (s->gpio_used)
+			WARN_ON(gpiochip_remove(&s->gpio));
+#endif
+	}
 
-	return 0;
+	return ret;
 
 err_freq:
 	dev_err(dev, "Frequency parameter incorrect\n");
-	ret = -EINVAL;
-
-err_out:
-	dev_set_drvdata(dev, NULL);
-
-	return ret;
+	return -EINVAL;
 }
 
-static int max310x_remove(struct spi_device *spi)
+static int max310x_remove(struct device *dev)
 {
-	struct device *dev = &spi->dev;
 	struct max310x_port *s = dev_get_drvdata(dev);
-	int ret = 0;
-
-	dev_dbg(dev, "Removing port\n");
-
-	devm_free_irq(dev, s->port.irq, s);
-
-	destroy_workqueue(s->wq);
+	int i, ret = 0;
 
-	uart_remove_one_port(&s->uart, &s->port);
+	for (i = 0; i < s->uart.nr; i++) {
+		cancel_work_sync(&s->p[i].tx_work);
+		uart_remove_one_port(&s->uart, &s->p[i].port);
+		s->devtype->power(&s->p[i].port, 0);
+	}
 
 	uart_unregister_driver(&s->uart);
 
 #ifdef CONFIG_GPIOLIB
-	if (s->pdata->gpio_base) {
+	if (s->gpio_used)
 		ret = gpiochip_remove(&s->gpio);
-		if (ret)
-			dev_err(dev, "Failed to remove gpio chip: %d\n", ret);
-	}
 #endif
 
-	dev_set_drvdata(dev, NULL);
-
-	if (s->pdata->suspend)
-		s->pdata->suspend(1);
 	if (s->pdata->exit)
 		s->pdata->exit();
 
 	return ret;
 }
 
+#ifdef CONFIG_SPI_MASTER
+static int max310x_spi_probe(struct spi_device *spi)
+{
+	struct max310x_devtype *devtype =
+		(struct max310x_devtype *)spi_get_device_id(spi)->driver_data;
+	int ret;
+
+	/* Setup SPI bus */
+	spi->bits_per_word	= 8;
+	spi->mode		= spi->mode ? : SPI_MODE_0;
+	spi->max_speed_hz	= spi->max_speed_hz ? : 26000000;
+	ret = spi_setup(spi);
+	if (ret) {
+		dev_err(&spi->dev, "SPI setup failed\n");
+		return ret;
+	}
+
+	return max310x_probe(&spi->dev, 1, devtype, spi->irq);
+}
+
+static int max310x_spi_remove(struct spi_device *spi)
+{
+	return max310x_remove(&spi->dev);
+}
+
+static SIMPLE_DEV_PM_OPS(max310x_pm_ops, max310x_suspend, max310x_resume);
+
 static const struct spi_device_id max310x_id_table[] = {
-	{ "max3107",	MAX310X_TYPE_MAX3107 },
-	{ "max3108",	MAX310X_TYPE_MAX3108 },
+	{ "max3107",	(kernel_ulong_t)&max3107_devtype, },
+	{ "max3108",	(kernel_ulong_t)&max3108_devtype, },
+	{ "max3109",	(kernel_ulong_t)&max3109_devtype, },
+	{ "max14830",	(kernel_ulong_t)&max14830_devtype, },
 	{ }
 };
 MODULE_DEVICE_TABLE(spi, max310x_id_table);
 
-static struct spi_driver max310x_driver = {
+static struct spi_driver max310x_uart_driver = {
 	.driver = {
-		.name	= "max310x",
+		.name	= MAX310X_NAME,
 		.owner	= THIS_MODULE,
-		.pm	= MAX310X_PM_OPS,
+		.pm	= &max310x_pm_ops,
 	},
-	.probe		= max310x_probe,
-	.remove		= max310x_remove,
+	.probe		= max310x_spi_probe,
+	.remove		= max310x_spi_remove,
 	.id_table	= max310x_id_table,
 };
-module_spi_driver(max310x_driver);
+module_spi_driver(max310x_uart_driver);
+#endif
 
-MODULE_LICENSE("GPL v2");
+MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Alexander Shiyan <shc_work@mail.ru>");
 MODULE_DESCRIPTION("MAX310X serial driver");
diff --git a/drivers/tty/serial/mcf.c b/drivers/tty/serial/mcf.c
index 65be0c00c4b..0edfaf8cd26 100644
--- a/drivers/tty/serial/mcf.c
+++ b/drivers/tty/serial/mcf.c
@@ -24,6 +24,7 @@
 #include <linux/serial_core.h>
 #include <linux/io.h>
 #include <linux/uaccess.h>
+#include <linux/platform_device.h>
 #include <asm/coldfire.h>
 #include <asm/mcfsim.h>
 #include <asm/mcfuart.h>
@@ -324,7 +325,9 @@ static void mcf_rx_chars(struct mcf_uart *pp)
 		uart_insert_char(port, status, MCFUART_USR_RXOVERRUN, ch, flag);
 	}
 
+	spin_unlock(&port->lock);
 	tty_flip_buffer_push(&port->state->port);
+	spin_lock(&port->lock);
 }
 
 /****************************************************************************/
@@ -644,7 +647,7 @@ static struct uart_driver mcf_driver = {
 
 static int mcf_probe(struct platform_device *pdev)
 {
-	struct mcf_platform_uart *platp = pdev->dev.platform_data;
+	struct mcf_platform_uart *platp = dev_get_platdata(&pdev->dev);
 	struct uart_port *port;
 	int i;
 
diff --git a/drivers/tty/serial/mfd.c b/drivers/tty/serial/mfd.c
index 4a82267af83..d3db042f649 100644
--- a/drivers/tty/serial/mfd.c
+++ b/drivers/tty/serial/mfd.c
@@ -386,7 +386,7 @@ static void serial_hsu_stop_tx(struct uart_port *port)
 
 /* This is always called in spinlock protected mode, so
  * modify timeout timer is safe here */
-void hsu_dma_rx(struct uart_hsu_port *up, u32 int_sts)
+void hsu_dma_rx(struct uart_hsu_port *up, u32 int_sts, unsigned long *flags)
 {
 	struct hsu_dma_buffer *dbuf = &up->rxbuf;
 	struct hsu_dma_chan *chan = up->rxc;
@@ -438,7 +438,9 @@ void hsu_dma_rx(struct uart_hsu_port *up, u32 int_sts)
 					 | (0x1 << 16)
 					 | (0x1 << 24)	/* timeout bit, see HSU Errata 1 */
 					 );
+	spin_unlock_irqrestore(&up->port.lock, *flags);
 	tty_flip_buffer_push(tport);
+	spin_lock_irqsave(&up->port.lock, *flags);
 
 	chan_writel(chan, HSU_CH_CR, 0x3);
 
@@ -459,7 +461,8 @@ static void serial_hsu_stop_rx(struct uart_port *port)
 	}
 }
 
-static inline void receive_chars(struct uart_hsu_port *up, int *status)
+static inline void receive_chars(struct uart_hsu_port *up, int *status,
+		unsigned long *flags)
 {
 	unsigned int ch, flag;
 	unsigned int max_count = 256;
@@ -519,7 +522,10 @@ static inline void receive_chars(struct uart_hsu_port *up, int *status)
 	ignore_char:
 		*status = serial_in(up, UART_LSR);
 	} while ((*status & UART_LSR_DR) && max_count--);
+
+	spin_unlock_irqrestore(&up->port.lock, *flags);
 	tty_flip_buffer_push(&up->port.state->port);
+	spin_lock_irqsave(&up->port.lock, *flags);
 }
 
 static void transmit_chars(struct uart_hsu_port *up)
@@ -613,7 +619,7 @@ static irqreturn_t port_irq(int irq, void *dev_id)
 
 	lsr = serial_in(up, UART_LSR);
 	if (lsr & UART_LSR_DR)
-		receive_chars(up, &lsr);
+		receive_chars(up, &lsr, &flags);
 	check_modem_status(up);
 
 	/* lsr will be renewed during the receive_chars */
@@ -643,7 +649,7 @@ static inline void dma_chan_irq(struct hsu_dma_chan *chan)
 
 	/* Rx channel */
 	if (chan->dirt == DMA_FROM_DEVICE)
-		hsu_dma_rx(up, int_sts);
+		hsu_dma_rx(up, int_sts, &flags);
 
 	/* Tx channel */
 	if (chan->dirt == DMA_TO_DEVICE) {
diff --git a/drivers/tty/serial/mpsc.c b/drivers/tty/serial/mpsc.c
index bc24f493167..8d702677acc 100644
--- a/drivers/tty/serial/mpsc.c
+++ b/drivers/tty/serial/mpsc.c
@@ -934,7 +934,7 @@ static int serial_polled;
  ******************************************************************************
  */
 
-static int mpsc_rx_intr(struct mpsc_port_info *pi)
+static int mpsc_rx_intr(struct mpsc_port_info *pi, unsigned long *flags)
 {
 	struct mpsc_rx_desc *rxre;
 	struct tty_port *port = &pi->port.state->port;
@@ -969,8 +969,11 @@ static int mpsc_rx_intr(struct mpsc_port_info *pi)
 #endif
 		/* Following use of tty struct directly is deprecated */
 		if (tty_buffer_request_room(port, bytes_in) < bytes_in) {
-			if (port->low_latency)
+			if (port->low_latency) {
+				spin_unlock_irqrestore(&pi->port.lock, *flags);
 				tty_flip_buffer_push(port);
+				spin_lock_irqsave(&pi->port.lock, *flags);
+			}
 			/*
 			 * If this failed then we will throw away the bytes
 			 * but must do so to clear interrupts.
@@ -1080,7 +1083,9 @@ next_frame:
 	if ((readl(pi->sdma_base + SDMA_SDCM) & SDMA_SDCM_ERD) == 0)
 		mpsc_start_rx(pi);
 
+	spin_unlock_irqrestore(&pi->port.lock, *flags);
 	tty_flip_buffer_push(port);
+	spin_lock_irqsave(&pi->port.lock, *flags);
 	return rc;
 }
 
@@ -1222,7 +1227,7 @@ static irqreturn_t mpsc_sdma_intr(int irq, void *dev_id)
 
 	spin_lock_irqsave(&pi->port.lock, iflags);
 	mpsc_sdma_intr_ack(pi);
-	if (mpsc_rx_intr(pi))
+	if (mpsc_rx_intr(pi, &iflags))
 		rc = IRQ_HANDLED;
 	if (mpsc_tx_intr(pi))
 		rc = IRQ_HANDLED;
@@ -1884,7 +1889,7 @@ static int mpsc_shared_drv_probe(struct platform_device *dev)
 	if (dev->id == 0) {
 		if (!(rc = mpsc_shared_map_regs(dev))) {
 			pdata = (struct mpsc_shared_pdata *)
-				dev->dev.platform_data;
+				dev_get_platdata(&dev->dev);
 
 			mpsc_shared_regs.MPSC_MRR_m = pdata->mrr_val;
 			mpsc_shared_regs.MPSC_RCRR_m= pdata->rcrr_val;
@@ -2025,7 +2030,7 @@ static void mpsc_drv_get_platform_data(struct mpsc_port_info *pi,
 {
 	struct mpsc_pdata	*pdata;
 
-	pdata = (struct mpsc_pdata *)pd->dev.platform_data;
+	pdata = (struct mpsc_pdata *)dev_get_platdata(&pd->dev);
 
 	pi->port.uartclk = pdata->brg_clk_freq;
 	pi->port.iotype = UPIO_MEM;
diff --git a/drivers/tty/serial/mrst_max3110.c b/drivers/tty/serial/mrst_max3110.c
index 9b6ef20420c..a67e7081f00 100644
--- a/drivers/tty/serial/mrst_max3110.c
+++ b/drivers/tty/serial/mrst_max3110.c
@@ -713,7 +713,7 @@ static void serial_m3110_enable_ms(struct uart_port *port)
 {
 }
 
-struct uart_ops serial_m3110_ops = {
+static struct uart_ops serial_m3110_ops = {
 	.tx_empty	= serial_m3110_tx_empty,
 	.set_mctrl	= serial_m3110_set_mctrl,
 	.get_mctrl	= serial_m3110_get_mctrl,
@@ -844,7 +844,7 @@ static int serial_m3110_probe(struct spi_device *spi)
 	pmax = max;
 
 	/* Give membase a psudo value to pass serial_core's check */
-	max->port.membase = (void *)0xff110000;
+	max->port.membase = (unsigned char __iomem *)0xff110000;
 	uart_add_one_port(&serial_m3110_reg, &max->port);
 
 	return 0;
diff --git a/drivers/tty/serial/msm_serial.c b/drivers/tty/serial/msm_serial.c
index 2c6cfb3cf03..b5d779cd3c2 100644
--- a/drivers/tty/serial/msm_serial.c
+++ b/drivers/tty/serial/msm_serial.c
@@ -45,16 +45,19 @@ struct msm_port {
 	struct clk		*clk;
 	struct clk		*pclk;
 	unsigned int		imr;
-	unsigned int            *gsbi_base;
+	void __iomem		*gsbi_base;
 	int			is_uartdm;
 	unsigned int		old_snap_state;
 };
 
-static inline void wait_for_xmitr(struct uart_port *port, int bits)
+static inline void wait_for_xmitr(struct uart_port *port)
 {
-	if (!(msm_read(port, UART_SR) & UART_SR_TX_EMPTY))
-		while ((msm_read(port, UART_ISR) & bits) != bits)
-			cpu_relax();
+	while (!(msm_read(port, UART_SR) & UART_SR_TX_EMPTY)) {
+		if (msm_read(port, UART_ISR) & UART_ISR_TX_READY)
+			break;
+		udelay(1);
+	}
+	msm_write(port, UART_CR_CMD_RESET_TX_READY, UART_CR);
 }
 
 static void msm_stop_tx(struct uart_port *port)
@@ -137,7 +140,10 @@ static void handle_rx_dm(struct uart_port *port, unsigned int misr)
 		count -= 4;
 	}
 
+	spin_unlock(&port->lock);
 	tty_flip_buffer_push(tport);
+	spin_lock(&port->lock);
+
 	if (misr & (UART_IMR_RXSTALE))
 		msm_write(port, UART_CR_CMD_RESET_STALE_INT, UART_CR);
 	msm_write(port, 0xFFFFFF, UARTDM_DMRX);
@@ -189,52 +195,69 @@ static void handle_rx(struct uart_port *port)
 			tty_insert_flip_char(tport, c, flag);
 	}
 
+	spin_unlock(&port->lock);
 	tty_flip_buffer_push(tport);
+	spin_lock(&port->lock);
 }
 
-static void reset_dm_count(struct uart_port *port)
+static void reset_dm_count(struct uart_port *port, int count)
 {
-	wait_for_xmitr(port, UART_ISR_TX_READY);
-	msm_write(port, 1, UARTDM_NCF_TX);
+	wait_for_xmitr(port);
+	msm_write(port, count, UARTDM_NCF_TX);
+	msm_read(port, UARTDM_NCF_TX);
 }
 
 static void handle_tx(struct uart_port *port)
 {
 	struct circ_buf *xmit = &port->state->xmit;
 	struct msm_port *msm_port = UART_TO_MSM(port);
-	int sent_tx;
+	unsigned int tx_count, num_chars;
+	unsigned int tf_pointer = 0;
+
+	tx_count = uart_circ_chars_pending(xmit);
+	tx_count = min3(tx_count, (unsigned int)UART_XMIT_SIZE - xmit->tail,
+			port->fifosize);
 
 	if (port->x_char) {
 		if (msm_port->is_uartdm)
-			reset_dm_count(port);
+			reset_dm_count(port, tx_count + 1);
 
 		msm_write(port, port->x_char,
 			  msm_port->is_uartdm ? UARTDM_TF : UART_TF);
 		port->icount.tx++;
 		port->x_char = 0;
+	} else if (tx_count && msm_port->is_uartdm) {
+		reset_dm_count(port, tx_count);
 	}
 
-	if (msm_port->is_uartdm)
-		reset_dm_count(port);
+	while (tf_pointer < tx_count) {
+		int i;
+		char buf[4] = { 0 };
+		unsigned int *bf = (unsigned int *)&buf;
 
-	while (msm_read(port, UART_SR) & UART_SR_TX_READY) {
-		if (uart_circ_empty(xmit)) {
-			/* disable tx interrupts */
-			msm_port->imr &= ~UART_IMR_TXLEV;
-			msm_write(port, msm_port->imr, UART_IMR);
+		if (!(msm_read(port, UART_SR) & UART_SR_TX_READY))
 			break;
-		}
-		msm_write(port, xmit->buf[xmit->tail],
-			  msm_port->is_uartdm ? UARTDM_TF : UART_TF);
 
 		if (msm_port->is_uartdm)
-			reset_dm_count(port);
+			num_chars = min(tx_count - tf_pointer,
+					(unsigned int)sizeof(buf));
+		else
+			num_chars = 1;
 
-		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
-		port->icount.tx++;
-		sent_tx = 1;
+		for (i = 0; i < num_chars; i++) {
+			buf[i] = xmit->buf[xmit->tail + i];
+			port->icount.tx++;
+		}
+
+		msm_write(port, *bf, msm_port->is_uartdm ? UARTDM_TF : UART_TF);
+		xmit->tail = (xmit->tail + num_chars) & (UART_XMIT_SIZE - 1);
+		tf_pointer += num_chars;
 	}
 
+	/* disable tx interrupts if nothing more to send */
+	if (uart_circ_empty(xmit))
+		msm_stop_tx(port);
+
 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 		uart_write_wakeup(port);
 }
@@ -295,7 +318,7 @@ static void msm_reset(struct uart_port *port)
 	msm_write(port, UART_CR_CMD_SET_RFR, UART_CR);
 }
 
-void msm_set_mctrl(struct uart_port *port, unsigned int mctrl)
+static void msm_set_mctrl(struct uart_port *port, unsigned int mctrl)
 {
 	unsigned int mr;
 	mr = msm_read(port, UART_MR1);
@@ -318,70 +341,60 @@ static void msm_break_ctl(struct uart_port *port, int break_ctl)
 		msm_write(port, UART_CR_CMD_STOP_BREAK, UART_CR);
 }
 
+struct msm_baud_map {
+	u16	divisor;
+	u8	code;
+	u8	rxstale;
+};
+
+static const struct msm_baud_map *
+msm_find_best_baud(struct uart_port *port, unsigned int baud)
+{
+	unsigned int i, divisor;
+	const struct msm_baud_map *entry;
+	static const struct msm_baud_map table[] = {
+		{ 1536, 0x00,  1 },
+		{  768, 0x11,  1 },
+		{  384, 0x22,  1 },
+		{  192, 0x33,  1 },
+		{   96, 0x44,  1 },
+		{   48, 0x55,  1 },
+		{   32, 0x66,  1 },
+		{   24, 0x77,  1 },
+		{   16, 0x88,  1 },
+		{   12, 0x99,  6 },
+		{    8, 0xaa,  6 },
+		{    6, 0xbb,  6 },
+		{    4, 0xcc,  6 },
+		{    3, 0xdd,  8 },
+		{    2, 0xee, 16 },
+		{    1, 0xff, 31 },
+	};
+
+	divisor = uart_get_divisor(port, baud);
+
+	for (i = 0, entry = table; i < ARRAY_SIZE(table); i++, entry++)
+		if (entry->divisor <= divisor)
+			break;
+
+	return entry; /* Default to smallest divider */
+}
+
 static int msm_set_baud_rate(struct uart_port *port, unsigned int baud)
 {
-	unsigned int baud_code, rxstale, watermark;
+	unsigned int rxstale, watermark;
 	struct msm_port *msm_port = UART_TO_MSM(port);
+	const struct msm_baud_map *entry;
 
-	switch (baud) {
-	case 300:
-		baud_code = UART_CSR_300;
-		rxstale = 1;
-		break;
-	case 600:
-		baud_code = UART_CSR_600;
-		rxstale = 1;
-		break;
-	case 1200:
-		baud_code = UART_CSR_1200;
-		rxstale = 1;
-		break;
-	case 2400:
-		baud_code = UART_CSR_2400;
-		rxstale = 1;
-		break;
-	case 4800:
-		baud_code = UART_CSR_4800;
-		rxstale = 1;
-		break;
-	case 9600:
-		baud_code = UART_CSR_9600;
-		rxstale = 2;
-		break;
-	case 14400:
-		baud_code = UART_CSR_14400;
-		rxstale = 3;
-		break;
-	case 19200:
-		baud_code = UART_CSR_19200;
-		rxstale = 4;
-		break;
-	case 28800:
-		baud_code = UART_CSR_28800;
-		rxstale = 6;
-		break;
-	case 38400:
-		baud_code = UART_CSR_38400;
-		rxstale = 8;
-		break;
-	case 57600:
-		baud_code = UART_CSR_57600;
-		rxstale = 16;
-		break;
-	case 115200:
-	default:
-		baud_code = UART_CSR_115200;
-		baud = 115200;
-		rxstale = 31;
-		break;
-	}
+	entry = msm_find_best_baud(port, baud);
 
 	if (msm_port->is_uartdm)
 		msm_write(port, UART_CR_CMD_RESET_RX, UART_CR);
 
-	msm_write(port, baud_code, UART_CSR);
+	msm_write(port, entry->code, UART_CSR);
 
 	/* RX stale watermark */
+	rxstale = entry->rxstale;
 	watermark = UART_IPR_STALE_LSB & rxstale;
 	watermark |= UART_IPR_RXSTALE_LAST;
 	watermark |= UART_IPR_STALE_TIMEOUT_MSB & (rxstale << 2);
@@ -409,8 +422,7 @@ static void msm_init_clock(struct uart_port *port)
 	struct msm_port *msm_port = UART_TO_MSM(port);
 
 	clk_prepare_enable(msm_port->clk);
-	if (!IS_ERR(msm_port->pclk))
-		clk_prepare_enable(msm_port->pclk);
+	clk_prepare_enable(msm_port->pclk);
 	msm_serial_set_mnd_regs(port);
 }
 
@@ -589,12 +601,10 @@ static void msm_release_port(struct uart_port *port)
 	port->membase = NULL;
 
 	if (msm_port->gsbi_base) {
-		iowrite32(GSBI_PROTOCOL_IDLE, msm_port->gsbi_base +
-			  GSBI_CONTROL);
-
-		gsbi_resource = platform_get_resource(pdev,
-							IORESOURCE_MEM, 1);
+		writel_relaxed(GSBI_PROTOCOL_IDLE,
+				msm_port->gsbi_base + GSBI_CONTROL);
 
+		gsbi_resource = platform_get_resource(pdev, IORESOURCE_MEM, 1);
 		if (unlikely(!gsbi_resource))
 			return;
 
@@ -637,7 +647,7 @@ static int msm_request_port(struct uart_port *port)
 		if (!request_mem_region(gsbi_resource->start, size,
 						 "msm_serial")) {
 			ret = -EBUSY;
-			goto fail_release_port;
+			goto fail_release_port_membase;
 		}
 
 		msm_port->gsbi_base = ioremap(gsbi_resource->start, size);
@@ -651,6 +661,8 @@ static int msm_request_port(struct uart_port *port)
 
 fail_release_gsbi:
 	release_mem_region(gsbi_resource->start, size);
+fail_release_port_membase:
+	iounmap(port->membase);
 fail_release_port:
 	release_mem_region(port->mapbase, size);
 	return ret;
@@ -666,10 +678,9 @@ static void msm_config_port(struct uart_port *port, int flags)
 		if (ret)
 			return;
 	}
-
-	if (msm_port->is_uartdm)
-		iowrite32(GSBI_PROTOCOL_UART, msm_port->gsbi_base +
-			  GSBI_CONTROL);
+	if (msm_port->gsbi_base)
+		writel_relaxed(GSBI_PROTOCOL_UART,
+				msm_port->gsbi_base + GSBI_CONTROL);
 }
 
 static int msm_verify_port(struct uart_port *port, struct serial_struct *ser)
@@ -689,13 +700,11 @@ static void msm_power(struct uart_port *port, unsigned int state,
 	switch (state) {
 	case 0:
 		clk_prepare_enable(msm_port->clk);
-		if (!IS_ERR(msm_port->pclk))
-			clk_prepare_enable(msm_port->pclk);
+		clk_prepare_enable(msm_port->pclk);
 		break;
 	case 3:
 		clk_disable_unprepare(msm_port->clk);
-		if (!IS_ERR(msm_port->pclk))
-			clk_disable_unprepare(msm_port->pclk);
+		clk_disable_unprepare(msm_port->pclk);
 		break;
 	default:
 		printk(KERN_ERR "msm_serial: Unknown PM state %d\n", state);
@@ -760,32 +769,63 @@ static inline struct uart_port *get_port_from_line(unsigned int line)
 }
 
 #ifdef CONFIG_SERIAL_MSM_CONSOLE
-
-static void msm_console_putchar(struct uart_port *port, int c)
-{
-	struct msm_port *msm_port = UART_TO_MSM(port);
-
-	if (msm_port->is_uartdm)
-		reset_dm_count(port);
-
-	while (!(msm_read(port, UART_SR) & UART_SR_TX_READY))
-		;
-	msm_write(port, c, msm_port->is_uartdm ? UARTDM_TF : UART_TF);
-}
-
 static void msm_console_write(struct console *co, const char *s,
 			      unsigned int count)
 {
+	int i;
 	struct uart_port *port;
 	struct msm_port *msm_port;
+	int num_newlines = 0;
+	bool replaced = false;
 
 	BUG_ON(co->index < 0 || co->index >= UART_NR);
 
 	port = get_port_from_line(co->index);
 	msm_port = UART_TO_MSM(port);
 
+	/* Account for newlines that will get a carriage return added */
+	for (i = 0; i < count; i++)
+		if (s[i] == '\n')
+			num_newlines++;
+	count += num_newlines;
+
 	spin_lock(&port->lock);
-	uart_console_write(port, s, count, msm_console_putchar);
+	if (msm_port->is_uartdm)
+		reset_dm_count(port, count);
+
+	i = 0;
+	while (i < count) {
+		int j;
+		unsigned int num_chars;
+		char buf[4] = { 0 };
+		unsigned int *bf = (unsigned int *)&buf;
+
+		if (msm_port->is_uartdm)
+			num_chars = min(count - i, (unsigned int)sizeof(buf));
+		else
+			num_chars = 1;
+
+		for (j = 0; j < num_chars; j++) {
+			char c = *s;
+
+			if (c == '\n' && !replaced) {
+				buf[j] = '\r';
+				j++;
+				replaced = true;
+			}
+			if (j < num_chars) {
+				buf[j] = c;
+				s++;
+				replaced = false;
+			}
+		}
+
+		while (!(msm_read(port, UART_SR) & UART_SR_TX_READY))
+			cpu_relax();
+
+		msm_write(port, *bf, msm_port->is_uartdm ? UARTDM_TF : UART_TF);
+		i += num_chars;
+	}
 	spin_unlock(&port->lock);
 }
 
@@ -859,6 +899,11 @@ static struct uart_driver msm_uart_driver = {
 
 static atomic_t msm_uart_next_id = ATOMIC_INIT(0);
 
+static const struct of_device_id msm_uartdm_table[] = {
+	{ .compatible = "qcom,msm-uartdm" },
+	{ }
+};
+
 static int __init msm_serial_probe(struct platform_device *pdev)
 {
 	struct msm_port *msm_port;
@@ -878,23 +923,17 @@ static int __init msm_serial_probe(struct platform_device *pdev)
 	port->dev = &pdev->dev;
 	msm_port = UART_TO_MSM(port);
 
-	if (platform_get_resource(pdev, IORESOURCE_MEM, 1))
+	if (of_match_device(msm_uartdm_table, &pdev->dev))
 		msm_port->is_uartdm = 1;
 	else
 		msm_port->is_uartdm = 0;
 
-	if (msm_port->is_uartdm) {
-		msm_port->clk = devm_clk_get(&pdev->dev, "gsbi_uart_clk");
-		msm_port->pclk = devm_clk_get(&pdev->dev, "gsbi_pclk");
-	} else {
-		msm_port->clk = devm_clk_get(&pdev->dev, "uart_clk");
-		msm_port->pclk = ERR_PTR(-ENOENT);
-	}
-
+	msm_port->clk = devm_clk_get(&pdev->dev, "core");
 	if (IS_ERR(msm_port->clk))
 		return PTR_ERR(msm_port->clk);
 
 	if (msm_port->is_uartdm) {
+		msm_port->pclk = devm_clk_get(&pdev->dev, "iface");
 		if (IS_ERR(msm_port->pclk))
 			return PTR_ERR(msm_port->pclk);
 
@@ -931,6 +970,7 @@ static int msm_serial_remove(struct platform_device *pdev)
 
 static struct of_device_id msm_match_table[] = {
 	{ .compatible = "qcom,msm-uart" },
+	{ .compatible = "qcom,msm-uartdm" },
 	{}
 };
 
diff --git a/drivers/tty/serial/msm_serial.h b/drivers/tty/serial/msm_serial.h
index e4acef5de77..469fda50ac6 100644
--- a/drivers/tty/serial/msm_serial.h
+++ b/drivers/tty/serial/msm_serial.h
@@ -38,19 +38,7 @@
 #define UART_MR2_PARITY_MODE_SPACE	0x3
 #define UART_MR2_PARITY_MODE		0x3
 
-#define UART_CSR	0x0008
-#define UART_CSR_115200	0xFF
-#define UART_CSR_57600	0xEE
-#define UART_CSR_38400	0xDD
-#define UART_CSR_28800	0xCC
-#define UART_CSR_19200	0xBB
-#define UART_CSR_14400	0xAA
-#define UART_CSR_9600	0x99
-#define UART_CSR_4800	0x77
-#define UART_CSR_2400	0x55
-#define UART_CSR_1200	0x44
-#define UART_CSR_600	0x33
-#define UART_CSR_300	0x22
+#define UART_CSR			0x0008
 
 #define UART_TF		0x000C
 #define UARTDM_TF	0x0070
@@ -71,6 +59,7 @@
 #define UART_CR_CMD_RESET_RFR		(14 << 4)
 #define UART_CR_CMD_PROTECTION_EN	(16 << 4)
 #define UART_CR_CMD_STALE_EVENT_ENABLE	(80 << 4)
+#define UART_CR_CMD_RESET_TX_READY	(3 << 8)
 #define UART_CR_TX_DISABLE		(1 << 3)
 #define UART_CR_TX_ENABLE		(1 << 2)
 #define UART_CR_RX_DISABLE		(1 << 1)
@@ -151,6 +140,7 @@ static inline void msm_serial_set_mnd_regs_tcxo(struct uart_port *port)
 	msm_write(port, 0xF1, UART_NREG);
 	msm_write(port, 0x0F, UART_DREG);
 	msm_write(port, 0x1A, UART_MNDREG);
+	port->uartclk = 1843200;
 }
 
 /*
@@ -162,6 +152,7 @@ static inline void msm_serial_set_mnd_regs_tcxoby4(struct uart_port *port)
 	msm_write(port, 0xF6, UART_NREG);
 	msm_write(port, 0x0F, UART_DREG);
 	msm_write(port, 0x0A, UART_MNDREG);
+	port->uartclk = 1843200;
 }
 
 static inline
@@ -169,7 +160,7 @@ void msm_serial_set_mnd_regs_from_uartclk(struct uart_port *port)
 {
 	if (port->uartclk == 19200000)
 		msm_serial_set_mnd_regs_tcxo(port);
-	else
+	else if (port->uartclk == 4800000)
 		msm_serial_set_mnd_regs_tcxoby4(port);
 }
 
diff --git a/drivers/tty/serial/msm_serial_hs.c b/drivers/tty/serial/msm_serial_hs.c
index 4ca2f64861e..48e94961a9e 100644
--- a/drivers/tty/serial/msm_serial_hs.c
+++ b/drivers/tty/serial/msm_serial_hs.c
@@ -1618,7 +1618,7 @@ static int msm_hs_probe(struct platform_device *pdev)
 	struct msm_hs_port *msm_uport;
 	struct resource *resource;
 	const struct msm_serial_hs_platform_data *pdata =
-						pdev->dev.platform_data;
+						dev_get_platdata(&pdev->dev);
 
 	if (pdev->id < 0 || pdev->id >= UARTDM_NR) {
 		printk(KERN_ERR "Invalid plaform device ID = %d\n", pdev->id);
diff --git a/drivers/tty/serial/mxs-auart.c b/drivers/tty/serial/mxs-auart.c
index f85b8e6d034..10e9d70b5c4 100644
--- a/drivers/tty/serial/mxs-auart.c
+++ b/drivers/tty/serial/mxs-auart.c
@@ -32,7 +32,6 @@
 #include <linux/clk.h>
 #include <linux/delay.h>
 #include <linux/io.h>
-#include <linux/pinctrl/consumer.h>
 #include <linux/of_device.h>
 #include <linux/dma-mapping.h>
 #include <linux/dmaengine.h>
@@ -134,10 +133,10 @@ enum mxs_auart_type {
 struct mxs_auart_port {
 	struct uart_port port;
 
-#define MXS_AUART_DMA_CONFIG	0x1
 #define MXS_AUART_DMA_ENABLED	0x2
 #define MXS_AUART_DMA_TX_SYNC	2  /* bit 2 */
 #define MXS_AUART_DMA_RX_READY	3  /* bit 3 */
+#define MXS_AUART_RTSCTS	4  /* bit 4 */
 	unsigned long flags;
 	unsigned int ctrl;
 	enum mxs_auart_type devtype;
@@ -640,7 +639,8 @@ static void mxs_auart_settermios(struct uart_port *u,
 		 * we can only implement the DMA support for auart
 		 * in mx28.
 		 */
-		if (is_imx28_auart(s) && (s->flags & MXS_AUART_DMA_CONFIG)) {
+		if (is_imx28_auart(s)
+				&& test_bit(MXS_AUART_RTSCTS, &s->flags)) {
 			if (!mxs_auart_dma_init(s))
 				/* enable DMA tranfer */
 				ctrl2 |= AUART_CTRL2_TXDMAE | AUART_CTRL2_RXDMAE
@@ -1008,7 +1008,8 @@ static int serial_mxs_probe_dt(struct mxs_auart_port *s,
 	}
 	s->port.line = ret;
 
-	s->flags |= MXS_AUART_DMA_CONFIG;
+	if (of_get_property(np, "fsl,uart-has-rtscts", NULL))
+		set_bit(MXS_AUART_RTSCTS, &s->flags);
 
 	return 0;
 }
@@ -1021,7 +1022,6 @@ static int mxs_auart_probe(struct platform_device *pdev)
 	u32 version;
 	int ret = 0;
 	struct resource *r;
-	struct pinctrl *pinctrl;
 
 	s = kzalloc(sizeof(struct mxs_auart_port), GFP_KERNEL);
 	if (!s) {
@@ -1035,12 +1035,6 @@ static int mxs_auart_probe(struct platform_device *pdev)
 	else if (ret < 0)
 		goto out_free;
 
-	pinctrl = devm_pinctrl_get_select_default(&pdev->dev);
-	if (IS_ERR(pinctrl)) {
-		ret = PTR_ERR(pinctrl);
-		goto out_free;
-	}
-
 	if (of_id) {
 		pdev->id_entry = of_id->data;
 		s->devtype = pdev->id_entry->driver_data;
diff --git a/drivers/tty/serial/netx-serial.c b/drivers/tty/serial/netx-serial.c
index b9a40ed70be..0a4dd70d29e 100644
--- a/drivers/tty/serial/netx-serial.c
+++ b/drivers/tty/serial/netx-serial.c
@@ -196,7 +196,7 @@ static void netx_txint(struct uart_port *port)
 		uart_write_wakeup(port);
 }
 
-static void netx_rxint(struct uart_port *port)
+static void netx_rxint(struct uart_port *port, unsigned long *flags)
 {
 	unsigned char rx, flg, status;
 
@@ -236,7 +236,9 @@ static void netx_rxint(struct uart_port *port)
 		uart_insert_char(port, status, SR_OE, rx, flg);
 	}
 
+	spin_unlock_irqrestore(&port->lock, *flags);
 	tty_flip_buffer_push(&port->state->port);
+	spin_lock_irqsave(&port->lock, *flags);
 }
 
 static irqreturn_t netx_int(int irq, void *dev_id)
@@ -250,7 +252,7 @@ static irqreturn_t netx_int(int irq, void *dev_id)
 	status = readl(port->membase + UART_IIR) & IIR_MASK;
 	while (status) {
 		if (status & IIR_RIS)
-			netx_rxint(port);
+			netx_rxint(port, &flags);
 		if (status & IIR_TIS)
 			netx_txint(port);
 		if (status & IIR_MIS) {
@@ -693,8 +695,6 @@ static int serial_netx_remove(struct platform_device *pdev)
 {
 	struct netx_port *sport = platform_get_drvdata(pdev);
 
-	platform_set_drvdata(pdev, NULL);
-
 	if (sport)
 		uart_remove_one_port(&netx_reg, &sport->port);
 
diff --git a/drivers/tty/serial/nwpserial.c b/drivers/tty/serial/nwpserial.c
index 549c70a2a63..693bc6c2561 100644
--- a/drivers/tty/serial/nwpserial.c
+++ b/drivers/tty/serial/nwpserial.c
@@ -149,7 +149,10 @@ static irqreturn_t nwpserial_interrupt(int irq, void *dev_id)
 			tty_insert_flip_char(port, ch, TTY_NORMAL);
 	} while (dcr_read(up->dcr_host, UART_LSR) & UART_LSR_DR);
 
+	spin_unlock(&up->port.lock);
 	tty_flip_buffer_push(port);
+	spin_lock(&up->port.lock);
+
 	ret = IRQ_HANDLED;
 
 	/* clear interrupt */
diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c
index b6d17287307..816d1a23f9d 100644
--- a/drivers/tty/serial/omap-serial.c
+++ b/drivers/tty/serial/omap-serial.c
@@ -40,9 +40,11 @@
 #include <linux/pm_runtime.h>
 #include <linux/of.h>
 #include <linux/gpio.h>
-#include <linux/pinctrl/consumer.h>
+#include <linux/of_gpio.h>
 #include <linux/platform_data/serial-omap.h>
 
+#include <dt-bindings/gpio/gpio.h>
+
 #define OMAP_MAX_HSUART_PORTS	6
 
 #define UART_BUILD_REVISION(x, y)	(((x) << 8) | (y))
@@ -52,6 +54,11 @@
 #define OMAP_UART_REV_52 0x0502
 #define OMAP_UART_REV_63 0x0603
 
+#define OMAP_UART_TX_WAKEUP_EN		BIT(7)
+
+/* Feature flags */
+#define OMAP_UART_WER_HAS_TX_WAKEUP	BIT(0)
+
 #define UART_ERRATA_i202_MDR1_ACCESS	BIT(0)
 #define UART_ERRATA_i291_DMA_FORCEIDLE	BIT(1)
 
@@ -137,6 +144,7 @@ struct uart_omap_port {
 	unsigned char		dlh;
 	unsigned char		mdr1;
 	unsigned char		scr;
+	unsigned char		wer;
 
 	int			use_dma;
 	/*
@@ -151,16 +159,19 @@ struct uart_omap_port {
 	int			context_loss_cnt;
 	u32			errata;
 	u8			wakeups_enabled;
+	u32			features;
 
 	int			DTR_gpio;
 	int			DTR_inverted;
 	int			DTR_active;
 
+	struct serial_rs485	rs485;
+	int			rts_gpio;
+
 	struct pm_qos_request	pm_qos_request;
 	u32			latency;
 	u32			calc_latency;
 	struct work_struct	qos_work;
-	struct pinctrl		*pins;
 	bool			is_suspending;
 };
 
@@ -195,7 +206,7 @@ static inline void serial_omap_clear_fifos(struct uart_omap_port *up)
 
 static int serial_omap_get_context_loss_count(struct uart_omap_port *up)
 {
-	struct omap_uart_port_info *pdata = up->dev->platform_data;
+	struct omap_uart_port_info *pdata = dev_get_platdata(up->dev);
 
 	if (!pdata || !pdata->get_context_loss_count)
 		return -EINVAL;
@@ -205,7 +216,7 @@ static int serial_omap_get_context_loss_count(struct uart_omap_port *up)
 
 static void serial_omap_enable_wakeup(struct uart_omap_port *up, bool enable)
 {
-	struct omap_uart_port_info *pdata = up->dev->platform_data;
+	struct omap_uart_port_info *pdata = dev_get_platdata(up->dev);
 
 	if (!pdata || !pdata->enable_wakeup)
 		return;
@@ -272,13 +283,42 @@ static void serial_omap_enable_ms(struct uart_port *port)
 static void serial_omap_stop_tx(struct uart_port *port)
 {
 	struct uart_omap_port *up = to_uart_omap_port(port);
+	struct circ_buf *xmit = &up->port.state->xmit;
+	int res;
 
 	pm_runtime_get_sync(up->dev);
+
+	/* handle rs485 */
+	if (up->rs485.flags & SER_RS485_ENABLED) {
+		/* do nothing if current tx not yet completed */
+		res = serial_in(up, UART_LSR) & UART_LSR_TEMT;
+		if (!res)
+			return;
+
+		/* if there's no more data to send, turn off rts */
+		if (uart_circ_empty(xmit)) {
+			/* if rts not already disabled */
+			res = (up->rs485.flags & SER_RS485_RTS_AFTER_SEND) ? 1 : 0;
+			if (gpio_get_value(up->rts_gpio) != res) {
+				if (up->rs485.delay_rts_after_send > 0) {
+					mdelay(up->rs485.delay_rts_after_send);
+				}
+				gpio_set_value(up->rts_gpio, res);
+			}
+		}
+	}
+
 	if (up->ier & UART_IER_THRI) {
 		up->ier &= ~UART_IER_THRI;
 		serial_out(up, UART_IER, up->ier);
 	}
 
+	if ((up->rs485.flags & SER_RS485_ENABLED) &&
+	    !(up->rs485.flags & SER_RS485_RX_DURING_TX)) {
+		up->ier = UART_IER_RLSI | UART_IER_RDI;
+		serial_out(up, UART_IER, up->ier);
+	}
+
 	pm_runtime_mark_last_busy(up->dev);
 	pm_runtime_put_autosuspend(up->dev);
 }
@@ -340,8 +380,26 @@ static inline void serial_omap_enable_ier_thri(struct uart_omap_port *up)
 static void serial_omap_start_tx(struct uart_port *port)
 {
 	struct uart_omap_port *up = to_uart_omap_port(port);
+	int res;
 
 	pm_runtime_get_sync(up->dev);
+
+	/* handle rs485 */
+	if (up->rs485.flags & SER_RS485_ENABLED) {
+		/* if rts not already enabled */
+		res = (up->rs485.flags & SER_RS485_RTS_ON_SEND) ? 1 : 0;
+		if (gpio_get_value(up->rts_gpio) != res) {
+			gpio_set_value(up->rts_gpio, res);
+			if (up->rs485.delay_rts_before_send > 0) {
+				mdelay(up->rs485.delay_rts_before_send);
+			}
+		}
+	}
+
+	if ((up->rs485.flags & SER_RS485_ENABLED) &&
+	    !(up->rs485.flags & SER_RS485_RX_DURING_TX))
+		serial_omap_stop_rx(port);
+
 	serial_omap_enable_ier_thri(up);
 	pm_runtime_mark_last_busy(up->dev);
 	pm_runtime_put_autosuspend(up->dev);
@@ -683,7 +741,11 @@ static int serial_omap_startup(struct uart_port *port)
 	serial_out(up, UART_IER, up->ier);
 
 	/* Enable module level wake up */
-	serial_out(up, UART_OMAP_WER, OMAP_UART_WER_MOD_WKUP);
+	up->wer = OMAP_UART_WER_MOD_WKUP;
+	if (up->features & OMAP_UART_WER_HAS_TX_WAKEUP)
+		up->wer |= OMAP_UART_TX_WAKEUP_EN;
+
+	serial_out(up, UART_OMAP_WER, up->wer);
 
 	pm_runtime_mark_last_busy(up->dev);
 	pm_runtime_put_autosuspend(up->dev);
@@ -1254,6 +1316,76 @@ static inline void serial_omap_add_console_port(struct uart_omap_port *up)
 
 #endif
 
+/* Enable or disable the rs485 support */
+static void
+serial_omap_config_rs485(struct uart_port *port, struct serial_rs485 *rs485conf)
+{
+	struct uart_omap_port *up = to_uart_omap_port(port);
+	unsigned long flags;
+	unsigned int mode;
+	int val;
+
+	pm_runtime_get_sync(up->dev);
+	spin_lock_irqsave(&up->port.lock, flags);
+
+	/* Disable interrupts from this port */
+	mode = up->ier;
+	up->ier = 0;
+	serial_out(up, UART_IER, 0);
+
+	/* store new config */
+	up->rs485 = *rs485conf;
+
+	/*
+	 * Just as a precaution, only allow rs485
+	 * to be enabled if the gpio pin is valid
+	 */
+	if (gpio_is_valid(up->rts_gpio)) {
+		/* enable / disable rts */
+		val = (up->rs485.flags & SER_RS485_ENABLED) ?
+			SER_RS485_RTS_AFTER_SEND : SER_RS485_RTS_ON_SEND;
+		val = (up->rs485.flags & val) ? 1 : 0;
+		gpio_set_value(up->rts_gpio, val);
+	} else
+		up->rs485.flags &= ~SER_RS485_ENABLED;
+
+	/* Enable interrupts */
+	up->ier = mode;
+	serial_out(up, UART_IER, up->ier);
+
+	spin_unlock_irqrestore(&up->port.lock, flags);
+	pm_runtime_mark_last_busy(up->dev);
+	pm_runtime_put_autosuspend(up->dev);
+}
+
+static int
+serial_omap_ioctl(struct uart_port *port, unsigned int cmd, unsigned long arg)
+{
+	struct serial_rs485 rs485conf;
+
+	switch (cmd) {
+	case TIOCSRS485:
+		if (copy_from_user(&rs485conf, (struct serial_rs485 *) arg,
+					sizeof(rs485conf)))
+			return -EFAULT;
+
+		serial_omap_config_rs485(port, &rs485conf);
+		break;
+
+	case TIOCGRS485:
+		if (copy_to_user((struct serial_rs485 *) arg,
+					&(to_uart_omap_port(port)->rs485),
+					sizeof(rs485conf)))
+			return -EFAULT;
+		break;
+
+	default:
+		return -ENOIOCTLCMD;
+	}
+	return 0;
+}
+
+
 static struct uart_ops serial_omap_pops = {
 	.tx_empty	= serial_omap_tx_empty,
 	.set_mctrl	= serial_omap_set_mctrl,
@@ -1275,6 +1407,7 @@ static struct uart_ops serial_omap_pops = {
 	.request_port	= serial_omap_request_port,
 	.config_port	= serial_omap_config_port,
 	.verify_port	= serial_omap_verify_port,
+	.ioctl		= serial_omap_ioctl,
 #ifdef CONFIG_CONSOLE_POLL
 	.poll_put_char  = serial_omap_poll_put_char,
 	.poll_get_char  = serial_omap_poll_get_char,
@@ -1334,7 +1467,7 @@ static void omap_serial_fill_features_erratas(struct uart_omap_port *up)
 	u32 mvr, scheme;
 	u16 revision, major, minor;
 
-	mvr = serial_in(up, UART_OMAP_MVER);
+	mvr = readl(up->port.membase + (UART_OMAP_MVER << up->port.regshift));
 
 	/* Check revision register scheme */
 	scheme = mvr >> OMAP_UART_MVR_SCHEME_SHIFT;
@@ -1373,9 +1506,11 @@ static void omap_serial_fill_features_erratas(struct uart_omap_port *up)
 	case OMAP_UART_REV_52:
 		up->errata |= (UART_ERRATA_i202_MDR1_ACCESS |
 				UART_ERRATA_i291_DMA_FORCEIDLE);
+		up->features |= OMAP_UART_WER_HAS_TX_WAKEUP;
 		break;
 	case OMAP_UART_REV_63:
 		up->errata |= UART_ERRATA_i202_MDR1_ACCESS;
+		up->features |= OMAP_UART_WER_HAS_TX_WAKEUP;
 		break;
 	default:
 		break;
@@ -1395,15 +1530,64 @@ static struct omap_uart_port_info *of_get_uart_port_info(struct device *dev)
 	return omap_up_info;
 }
 
+static int serial_omap_probe_rs485(struct uart_omap_port *up,
+				   struct device_node *np)
+{
+	struct serial_rs485 *rs485conf = &up->rs485;
+	u32 rs485_delay[2];
+	enum of_gpio_flags flags;
+	int ret;
+
+	rs485conf->flags = 0;
+	up->rts_gpio = -EINVAL;
+
+	if (!np)
+		return 0;
+
+	if (of_property_read_bool(np, "rs485-rts-active-high"))
+		rs485conf->flags |= SER_RS485_RTS_ON_SEND;
+	else
+		rs485conf->flags |= SER_RS485_RTS_AFTER_SEND;
+
+	/* check for tx enable gpio */
+	up->rts_gpio = of_get_named_gpio_flags(np, "rts-gpio", 0, &flags);
+	if (gpio_is_valid(up->rts_gpio)) {
+		ret = gpio_request(up->rts_gpio, "omap-serial");
+		if (ret < 0)
+			return ret;
+		ret = gpio_direction_output(up->rts_gpio,
+					    flags & SER_RS485_RTS_AFTER_SEND);
+		if (ret < 0)
+			return ret;
+	} else
+		up->rts_gpio = -EINVAL;
+
+	if (of_property_read_u32_array(np, "rs485-rts-delay",
+				    rs485_delay, 2) == 0) {
+		rs485conf->delay_rts_before_send = rs485_delay[0];
+		rs485conf->delay_rts_after_send = rs485_delay[1];
+	}
+
+	if (of_property_read_bool(np, "rs485-rx-during-tx"))
+		rs485conf->flags |= SER_RS485_RX_DURING_TX;
+
+	if (of_property_read_bool(np, "linux,rs485-enabled-at-boot-time"))
+		rs485conf->flags |= SER_RS485_ENABLED;
+
+	return 0;
+}
+
 static int serial_omap_probe(struct platform_device *pdev)
 {
 	struct uart_omap_port	*up;
 	struct resource		*mem, *irq;
-	struct omap_uart_port_info *omap_up_info = pdev->dev.platform_data;
+	struct omap_uart_port_info *omap_up_info = dev_get_platdata(&pdev->dev);
 	int ret;
 
-	if (pdev->dev.of_node)
+	if (pdev->dev.of_node) {
 		omap_up_info = of_get_uart_port_info(&pdev->dev);
+		pdev->dev.platform_data = omap_up_info;
+	}
 
 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	if (!mem) {
@@ -1468,12 +1652,9 @@ static int serial_omap_probe(struct platform_device *pdev)
 		goto err_port_line;
 	}
 
-	up->pins = devm_pinctrl_get_select_default(&pdev->dev);
-	if (IS_ERR(up->pins)) {
-		dev_warn(&pdev->dev, "did not get pins for uart%i error: %li\n",
-			 up->port.line, PTR_ERR(up->pins));
-		up->pins = NULL;
-	}
+	ret = serial_omap_probe_rs485(up, pdev->dev.of_node);
+	if (ret < 0)
+		goto err_rs485;
 
 	sprintf(up->name, "OMAP UART%d", up->port.line);
 	up->port.mapbase = mem->start;
@@ -1501,7 +1682,6 @@ static int serial_omap_probe(struct platform_device *pdev)
 	INIT_WORK(&up->qos_work, serial_omap_uart_qos_work);
 
 	platform_set_drvdata(pdev, up);
-	pm_runtime_enable(&pdev->dev);
 	if (omap_up_info->autosuspend_timeout == 0)
 		omap_up_info->autosuspend_timeout = -1;
 	device_init_wakeup(up->dev, true);
@@ -1510,6 +1690,8 @@ static int serial_omap_probe(struct platform_device *pdev)
 			omap_up_info->autosuspend_timeout);
 
 	pm_runtime_irq_safe(&pdev->dev);
+	pm_runtime_enable(&pdev->dev);
+
 	pm_runtime_get_sync(&pdev->dev);
 
 	omap_serial_fill_features_erratas(up);
@@ -1529,6 +1711,7 @@ err_add_port:
 	pm_runtime_put(&pdev->dev);
 	pm_runtime_disable(&pdev->dev);
 err_ioremap:
+err_rs485:
 err_port_line:
 	dev_err(&pdev->dev, "[UART%d]: failure [%s]: %d\n",
 				pdev->id, __func__, ret);
@@ -1609,6 +1792,7 @@ static void serial_omap_restore_context(struct uart_omap_port *up)
 		serial_omap_mdr1_errataset(up, up->mdr1);
 	else
 		serial_out(up, UART_OMAP_MDR1, up->mdr1);
+	serial_out(up, UART_OMAP_WER, up->wer);
 }
 
 static int serial_omap_runtime_suspend(struct device *dev)
diff --git a/drivers/tty/serial/pch_uart.c b/drivers/tty/serial/pch_uart.c
index 572d48189de..52379e56a31 100644
--- a/drivers/tty/serial/pch_uart.c
+++ b/drivers/tty/serial/pch_uart.c
@@ -232,7 +232,7 @@ struct eg20t_port {
 	unsigned int iobase;
 	struct pci_dev *pdev;
 	int fifo_size;
-	int uartclk;
+	unsigned int uartclk;
 	int start_tx;
 	int start_rx;
 	int tx_empty;
@@ -373,35 +373,62 @@ static const struct file_operations port_regs_ops = {
 };
 #endif	/* CONFIG_DEBUG_FS */
 
+static struct dmi_system_id pch_uart_dmi_table[] = {
+	{
+		.ident = "CM-iTC",
+		{
+			DMI_MATCH(DMI_BOARD_NAME, "CM-iTC"),
+		},
+		(void *)CMITC_UARTCLK,
+	},
+	{
+		.ident = "FRI2",
+		{
+			DMI_MATCH(DMI_BIOS_VERSION, "FRI2"),
+		},
+		(void *)FRI2_64_UARTCLK,
+	},
+	{
+		.ident = "Fish River Island II",
+		{
+			DMI_MATCH(DMI_PRODUCT_NAME, "Fish River Island II"),
+		},
+		(void *)FRI2_48_UARTCLK,
+	},
+	{
+		.ident = "COMe-mTT",
+		{
+			DMI_MATCH(DMI_BOARD_NAME, "COMe-mTT"),
+		},
+		(void *)NTC1_UARTCLK,
+	},
+	{
+		.ident = "nanoETXexpress-TT",
+		{
+			DMI_MATCH(DMI_BOARD_NAME, "nanoETXexpress-TT"),
+		},
+		(void *)NTC1_UARTCLK,
+	},
+	{
+		.ident = "MinnowBoard",
+		{
+			DMI_MATCH(DMI_BOARD_NAME, "MinnowBoard"),
+		},
+		(void *)MINNOW_UARTCLK,
+	},
+};
+
 /* Return UART clock, checking for board specific clocks. */
-static int pch_uart_get_uartclk(void)
+static unsigned int pch_uart_get_uartclk(void)
 {
-	const char *cmp;
+	const struct dmi_system_id *d;
 
 	if (user_uartclk)
 		return user_uartclk;
 
-	cmp = dmi_get_system_info(DMI_BOARD_NAME);
-	if (cmp && strstr(cmp, "CM-iTC"))
-		return CMITC_UARTCLK;
-
-	cmp = dmi_get_system_info(DMI_BIOS_VERSION);
-	if (cmp && strnstr(cmp, "FRI2", 4))
-		return FRI2_64_UARTCLK;
-
-	cmp = dmi_get_system_info(DMI_PRODUCT_NAME);
-	if (cmp && strstr(cmp, "Fish River Island II"))
-		return FRI2_48_UARTCLK;
-
-	/* Kontron COMe-mTT10 (nanoETXexpress-TT) */
-	cmp = dmi_get_system_info(DMI_BOARD_NAME);
-	if (cmp && (strstr(cmp, "COMe-mTT") ||
-		    strstr(cmp, "nanoETXexpress-TT")))
-		return NTC1_UARTCLK;
-
-	cmp = dmi_get_system_info(DMI_BOARD_NAME);
-	if (cmp && strstr(cmp, "MinnowBoard"))
-		return MINNOW_UARTCLK;
+	d = dmi_first_match(pch_uart_dmi_table);
+	if (d)
+		return (unsigned long)d->driver_data;
 
 	return DEFAULT_UARTCLK;
 }
@@ -422,7 +449,7 @@ static void pch_uart_hal_disable_interrupt(struct eg20t_port *priv,
 	iowrite8(ier, priv->membase + UART_IER);
 }
 
-static int pch_uart_hal_set_line(struct eg20t_port *priv, int baud,
+static int pch_uart_hal_set_line(struct eg20t_port *priv, unsigned int baud,
 				 unsigned int parity, unsigned int bits,
 				 unsigned int stb)
 {
@@ -457,7 +484,7 @@ static int pch_uart_hal_set_line(struct eg20t_port *priv, int baud,
 	lcr |= bits;
 	lcr |= stb;
 
-	dev_dbg(priv->port.dev, "%s:baud = %d, div = %04x, lcr = %02x (%lu)\n",
+	dev_dbg(priv->port.dev, "%s:baud = %u, div = %04x, lcr = %02x (%lu)\n",
 		 __func__, baud, div, lcr, jiffies);
 	iowrite8(PCH_UART_LCR_DLAB, priv->membase + UART_LCR);
 	iowrite8(dll, priv->membase + PCH_UART_DLL);
@@ -1363,9 +1390,8 @@ static void pch_uart_shutdown(struct uart_port *port)
 static void pch_uart_set_termios(struct uart_port *port,
 				 struct ktermios *termios, struct ktermios *old)
 {
-	int baud;
 	int rtn;
-	unsigned int parity, bits, stb;
+	unsigned int baud, parity, bits, stb;
 	struct eg20t_port *priv;
 	unsigned long flags;
 
@@ -1498,6 +1524,7 @@ static int pch_uart_verify_port(struct uart_port *port,
 	return 0;
 }
 
+#if defined(CONFIG_CONSOLE_POLL) || defined(CONFIG_SERIAL_PCH_UART_CONSOLE)
 /*
  *	Wait for transmitter & holding register to empty
  */
@@ -1528,6 +1555,7 @@ static void wait_for_xmitr(struct eg20t_port *up, int bits)
 		}
 	}
 }
+#endif /* CONFIG_CONSOLE_POLL || CONFIG_SERIAL_PCH_UART_CONSOLE */
 
 #ifdef CONFIG_CONSOLE_POLL
 /*
diff --git a/drivers/tty/serial/pmac_zilog.c b/drivers/tty/serial/pmac_zilog.c
index b1785f58b6e..f87f1a0c8c6 100644
--- a/drivers/tty/serial/pmac_zilog.c
+++ b/drivers/tty/serial/pmac_zilog.c
@@ -1798,7 +1798,6 @@ static int __exit pmz_detach(struct platform_device *pdev)
 
 	uart_remove_one_port(&pmz_uart_reg, &uap->port);
 
-	platform_set_drvdata(pdev, NULL);
 	uap->port.dev = NULL;
 
 	return 0;
diff --git a/drivers/tty/serial/pnx8xxx_uart.c b/drivers/tty/serial/pnx8xxx_uart.c
index 7e277a5384a..de6c05c6368 100644
--- a/drivers/tty/serial/pnx8xxx_uart.c
+++ b/drivers/tty/serial/pnx8xxx_uart.c
@@ -237,7 +237,10 @@ static void pnx8xxx_rx_chars(struct pnx8xxx_port *sport)
 		status = FIFO_TO_SM(serial_in(sport, PNX8XXX_FIFO)) |
 			 ISTAT_TO_SM(serial_in(sport, PNX8XXX_ISTAT));
 	}
+
+	spin_unlock(&sport->port.lock);
 	tty_flip_buffer_push(&sport->port.state->port);
+	spin_lock(&sport->port.lock);
 }
 
 static void pnx8xxx_tx_chars(struct pnx8xxx_port *sport)
@@ -801,8 +804,6 @@ static int pnx8xxx_serial_remove(struct platform_device *pdev)
 {
 	struct pnx8xxx_port *sport = platform_get_drvdata(pdev);
 
-	platform_set_drvdata(pdev, NULL);
-
 	if (sport)
 		uart_remove_one_port(&pnx8xxx_reg, &sport->port);
 
diff --git a/drivers/tty/serial/pxa.c b/drivers/tty/serial/pxa.c
index 05f504e0c27..f9f20f38376 100644
--- a/drivers/tty/serial/pxa.c
+++ b/drivers/tty/serial/pxa.c
@@ -332,31 +332,6 @@ static void serial_pxa_break_ctl(struct uart_port *port, int break_state)
 	spin_unlock_irqrestore(&up->port.lock, flags);
 }
 
-#if 0
-static void serial_pxa_dma_init(struct pxa_uart *up)
-{
-	up->rxdma =
-		pxa_request_dma(up->name, DMA_PRIO_LOW, pxa_receive_dma, up);
-	if (up->rxdma < 0)
-		goto out;
-	up->txdma =
-		pxa_request_dma(up->name, DMA_PRIO_LOW, pxa_transmit_dma, up);
-	if (up->txdma < 0)
-		goto err_txdma;
-	up->dmadesc = kmalloc(4 * sizeof(pxa_dma_desc), GFP_KERNEL);
-	if (!up->dmadesc)
-		goto err_alloc;
-
-	/* ... */
-err_alloc:
-	pxa_free_dma(up->txdma);
-err_rxdma:
-	pxa_free_dma(up->rxdma);
-out:
-	return;
-}
-#endif
-
 static int serial_pxa_startup(struct uart_port *port)
 {
 	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
@@ -790,7 +765,7 @@ static struct console serial_pxa_console = {
 #define PXA_CONSOLE	NULL
 #endif
 
-struct uart_ops serial_pxa_pops = {
+static struct uart_ops serial_pxa_pops = {
 	.tx_empty	= serial_pxa_tx_empty,
 	.set_mctrl	= serial_pxa_set_mctrl,
 	.get_mctrl	= serial_pxa_get_mctrl,
@@ -945,8 +920,6 @@ static int serial_pxa_remove(struct platform_device *dev)
 {
 	struct uart_pxa_port *sport = platform_get_drvdata(dev);
 
-	platform_set_drvdata(dev, NULL);
-
 	uart_remove_one_port(&serial_pxa_reg, &sport->port);
 
 	clk_unprepare(sport->clk);
@@ -970,7 +943,7 @@ static struct platform_driver serial_pxa_driver = {
 	},
 };
 
-int __init serial_pxa_init(void)
+static int __init serial_pxa_init(void)
 {
 	int ret;
 
@@ -985,7 +958,7 @@ int __init serial_pxa_init(void)
 	return ret;
 }
 
-void __exit serial_pxa_exit(void)
+static void __exit serial_pxa_exit(void)
 {
 	platform_driver_unregister(&serial_pxa_driver);
 	uart_unregister_driver(&serial_pxa_reg);
diff --git a/drivers/tty/serial/rp2.c b/drivers/tty/serial/rp2.c
index a314a943f12..328d6deb6b0 100644
--- a/drivers/tty/serial/rp2.c
+++ b/drivers/tty/serial/rp2.c
@@ -427,7 +427,9 @@ static void rp2_rx_chars(struct rp2_uart_port *up)
 		up->port.icount.rx++;
 	}
 
+	spin_unlock(&up->port.lock);
 	tty_flip_buffer_push(port);
+	spin_lock(&up->port.lock);
 }
 
 static void rp2_tx_chars(struct rp2_uart_port *up)
diff --git a/drivers/tty/serial/sa1100.c b/drivers/tty/serial/sa1100.c
index af6b3e3ad24..ba25722a713 100644
--- a/drivers/tty/serial/sa1100.c
+++ b/drivers/tty/serial/sa1100.c
@@ -232,7 +232,10 @@ sa1100_rx_chars(struct sa1100_port *sport)
 		status = UTSR1_TO_SM(UART_GET_UTSR1(sport)) |
 			 UTSR0_TO_SM(UART_GET_UTSR0(sport));
 	}
+
+	spin_unlock(&sport->port.lock);
 	tty_flip_buffer_push(&sport->port.state->port);
+	spin_lock(&sport->port.lock);
 }
 
 static void sa1100_tx_chars(struct sa1100_port *sport)
@@ -864,8 +867,6 @@ static int sa1100_serial_remove(struct platform_device *pdev)
 {
 	struct sa1100_port *sport = platform_get_drvdata(pdev);
 
-	platform_set_drvdata(pdev, NULL);
-
 	if (sport)
 		uart_remove_one_port(&sa1100_reg, &sport->port);
 
diff --git a/drivers/tty/serial/samsung.c b/drivers/tty/serial/samsung.c
index 376079b9bd7..f3dfa19a1cb 100644
--- a/drivers/tty/serial/samsung.c
+++ b/drivers/tty/serial/samsung.c
@@ -249,6 +249,8 @@ s3c24xx_serial_rx_chars(int irq, void *dev_id)
 					ufcon |= S3C2410_UFCON_RESETRX;
 					wr_regl(port, S3C2410_UFCON, ufcon);
 					rx_enabled(port) = 1;
+					spin_unlock_irqrestore(&port->lock,
+							flags);
 					goto out;
 				}
 				continue;
@@ -297,10 +299,11 @@ s3c24xx_serial_rx_chars(int irq, void *dev_id)
  ignore_char:
 		continue;
 	}
+
+	spin_unlock_irqrestore(&port->lock, flags);
 	tty_flip_buffer_push(&port->state->port);
 
  out:
-	spin_unlock_irqrestore(&port->lock, flags);
 	return IRQ_HANDLED;
 }
 
@@ -1250,8 +1253,8 @@ static int s3c24xx_serial_probe(struct platform_device *pdev)
 
 	ourport->baudclk = ERR_PTR(-EINVAL);
 	ourport->info = ourport->drv_data->info;
-	ourport->cfg = (pdev->dev.platform_data) ?
-			(struct s3c2410_uartcfg *)pdev->dev.platform_data :
+	ourport->cfg = (dev_get_platdata(&pdev->dev)) ?
+			(struct s3c2410_uartcfg *)dev_get_platdata(&pdev->dev) :
 			ourport->drv_data->def_cfg;
 
 	ourport->port.fifosize = (ourport->info->fifosize) ?
diff --git a/drivers/tty/serial/samsung.h b/drivers/tty/serial/samsung.h
index 00a499ecd38..aaa617a6c49 100644
--- a/drivers/tty/serial/samsung.h
+++ b/drivers/tty/serial/samsung.h
@@ -68,7 +68,8 @@ struct s3c24xx_uart_port {
 /* register access controls */
 
 #define portaddr(port, reg) ((port)->membase + (reg))
-#define portaddrl(port, reg) ((unsigned long *)((port)->membase + (reg)))
+#define portaddrl(port, reg) \
+	((unsigned long *)(unsigned long)((port)->membase + (reg)))
 
 #define rd_regb(port, reg) (__raw_readb(portaddr(port, reg)))
 #define rd_regl(port, reg) (__raw_readl(portaddr(port, reg)))
diff --git a/drivers/tty/serial/sc26xx.c b/drivers/tty/serial/sc26xx.c
index 4b1434d53e9..887b4f77074 100644
--- a/drivers/tty/serial/sc26xx.c
+++ b/drivers/tty/serial/sc26xx.c
@@ -637,7 +637,7 @@ static int sc26xx_probe(struct platform_device *dev)
 {
 	struct resource *res;
 	struct uart_sc26xx_port *up;
-	unsigned int *sc26xx_data = dev->dev.platform_data;
+	unsigned int *sc26xx_data = dev_get_platdata(&dev->dev);
 	int err;
 
 	res = platform_get_resource(dev, IORESOURCE_MEM, 0);
diff --git a/drivers/tty/serial/sccnxp.c b/drivers/tty/serial/sccnxp.c
index c7730415541..49e9bbfe6ca 100644
--- a/drivers/tty/serial/sccnxp.c
+++ b/drivers/tty/serial/sccnxp.c
@@ -15,6 +15,7 @@
 #define SUPPORT_SYSRQ
 #endif
 
+#include <linux/clk.h>
 #include <linux/err.h>
 #include <linux/module.h>
 #include <linux/device.h>
@@ -94,16 +95,17 @@
 #define MCTRL_IBIT(cfg, sig)		((((cfg) >> (sig)) & 0xf) - LINE_IP0)
 #define MCTRL_OBIT(cfg, sig)		((((cfg) >> (sig)) & 0xf) - LINE_OP0)
 
-/* Supported chip types */
-enum {
-	SCCNXP_TYPE_SC2681	= 2681,
-	SCCNXP_TYPE_SC2691	= 2691,
-	SCCNXP_TYPE_SC2692	= 2692,
-	SCCNXP_TYPE_SC2891	= 2891,
-	SCCNXP_TYPE_SC2892	= 2892,
-	SCCNXP_TYPE_SC28202	= 28202,
-	SCCNXP_TYPE_SC68681	= 68681,
-	SCCNXP_TYPE_SC68692	= 68692,
+#define SCCNXP_HAVE_IO		0x00000001
+#define SCCNXP_HAVE_MR0		0x00000002
+
+struct sccnxp_chip {
+	const char		*name;
+	unsigned int		nr;
+	unsigned long		freq_min;
+	unsigned long		freq_std;
+	unsigned long		freq_max;
+	unsigned int		flags;
+	unsigned int		fifosize;
 };
 
 struct sccnxp_port {
@@ -111,16 +113,10 @@ struct sccnxp_port {
 	struct uart_port	port[SCCNXP_MAX_UARTS];
 	bool			opened[SCCNXP_MAX_UARTS];
 
-	const char		*name;
 	int			irq;
-
 	u8			imr;
-	u8			addr_mask;
-	int			freq_std;
 
-	int			flags;
-#define SCCNXP_HAVE_IO		0x00000001
-#define SCCNXP_HAVE_MR0		0x00000002
+	struct sccnxp_chip	*chip;
 
 #ifdef CONFIG_SERIAL_SCCNXP_CONSOLE
 	struct console		console;
@@ -136,29 +132,94 @@ struct sccnxp_port {
 	struct regulator	*regulator;
 };
 
-static inline u8 sccnxp_raw_read(void __iomem *base, u8 reg, u8 shift)
-{
-	return readb(base + (reg << shift));
-}
+static const struct sccnxp_chip sc2681 = {
+	.name		= "SC2681",
+	.nr		= 2,
+	.freq_min	= 1000000,
+	.freq_std	= 3686400,
+	.freq_max	= 4000000,
+	.flags		= SCCNXP_HAVE_IO,
+	.fifosize	= 3,
+};
 
-static inline void sccnxp_raw_write(void __iomem *base, u8 reg, u8 shift, u8 v)
-{
-	writeb(v, base + (reg << shift));
-}
+static const struct sccnxp_chip sc2691 = {
+	.name		= "SC2691",
+	.nr		= 1,
+	.freq_min	= 1000000,
+	.freq_std	= 3686400,
+	.freq_max	= 4000000,
+	.flags		= 0,
+	.fifosize	= 3,
+};
+
+static const struct sccnxp_chip sc2692 = {
+	.name		= "SC2692",
+	.nr		= 2,
+	.freq_min	= 1000000,
+	.freq_std	= 3686400,
+	.freq_max	= 4000000,
+	.flags		= SCCNXP_HAVE_IO,
+	.fifosize	= 3,
+};
+
+static const struct sccnxp_chip sc2891 = {
+	.name		= "SC2891",
+	.nr		= 1,
+	.freq_min	= 100000,
+	.freq_std	= 3686400,
+	.freq_max	= 8000000,
+	.flags		= SCCNXP_HAVE_IO | SCCNXP_HAVE_MR0,
+	.fifosize	= 16,
+};
+
+static const struct sccnxp_chip sc2892 = {
+	.name		= "SC2892",
+	.nr		= 2,
+	.freq_min	= 100000,
+	.freq_std	= 3686400,
+	.freq_max	= 8000000,
+	.flags		= SCCNXP_HAVE_IO | SCCNXP_HAVE_MR0,
+	.fifosize	= 16,
+};
+
+static const struct sccnxp_chip sc28202 = {
+	.name		= "SC28202",
+	.nr		= 2,
+	.freq_min	= 1000000,
+	.freq_std	= 14745600,
+	.freq_max	= 50000000,
+	.flags		= SCCNXP_HAVE_IO | SCCNXP_HAVE_MR0,
+	.fifosize	= 256,
+};
+
+static const struct sccnxp_chip sc68681 = {
+	.name		= "SC68681",
+	.nr		= 2,
+	.freq_min	= 1000000,
+	.freq_std	= 3686400,
+	.freq_max	= 4000000,
+	.flags		= SCCNXP_HAVE_IO,
+	.fifosize	= 3,
+};
+
+static const struct sccnxp_chip sc68692 = {
+	.name		= "SC68692",
+	.nr		= 2,
+	.freq_min	= 1000000,
+	.freq_std	= 3686400,
+	.freq_max	= 4000000,
+	.flags		= SCCNXP_HAVE_IO,
+	.fifosize	= 3,
+};
 
 static inline u8 sccnxp_read(struct uart_port *port, u8 reg)
 {
-	struct sccnxp_port *s = dev_get_drvdata(port->dev);
-
-	return sccnxp_raw_read(port->membase, reg & s->addr_mask,
-			       port->regshift);
+	return readb(port->membase + (reg << port->regshift));
 }
 
 static inline void sccnxp_write(struct uart_port *port, u8 reg, u8 v)
 {
-	struct sccnxp_port *s = dev_get_drvdata(port->dev);
-
-	sccnxp_raw_write(port->membase, reg & s->addr_mask, port->regshift, v);
+	writeb(v, port->membase + (reg << port->regshift));
 }
 
 static inline u8 sccnxp_port_read(struct uart_port *port, u8 reg)
@@ -224,13 +285,14 @@ static int sccnxp_set_baud(struct uart_port *port, int baud)
 {
 	struct sccnxp_port *s = dev_get_drvdata(port->dev);
 	int div_std, tmp_baud, bestbaud = baud, besterr = -1;
+	struct sccnxp_chip *chip = s->chip;
 	u8 i, acr = 0, csr = 0, mr0 = 0;
 
 	/* Find best baud from table */
 	for (i = 0; baud_std[i].baud && besterr; i++) {
-		if (baud_std[i].mr0 && !(s->flags & SCCNXP_HAVE_MR0))
+		if (baud_std[i].mr0 && !(chip->flags & SCCNXP_HAVE_MR0))
 			continue;
-		div_std = DIV_ROUND_CLOSEST(s->freq_std, baud_std[i].baud);
+		div_std = DIV_ROUND_CLOSEST(chip->freq_std, baud_std[i].baud);
 		tmp_baud = DIV_ROUND_CLOSEST(port->uartclk, div_std);
 		if (!sccnxp_update_best_err(baud, tmp_baud, &besterr)) {
 			acr = baud_std[i].acr;
@@ -240,7 +302,7 @@ static int sccnxp_set_baud(struct uart_port *port, int baud)
 		}
 	}
 
-	if (s->flags & SCCNXP_HAVE_MR0) {
+	if (chip->flags & SCCNXP_HAVE_MR0) {
 		/* Enable FIFO, set half level for TX */
 		mr0 |= MR0_FIFO | MR0_TXLVL;
 		/* Update MR0 */
@@ -363,7 +425,7 @@ static void sccnxp_handle_tx(struct uart_port *port)
 			sccnxp_disable_irq(port, IMR_TXRDY);
 
 			/* Set direction to input */
-			if (s->flags & SCCNXP_HAVE_IO)
+			if (s->chip->flags & SCCNXP_HAVE_IO)
 				sccnxp_set_bit(port, DIR_OP, 0);
 		}
 		return;
@@ -437,7 +499,7 @@ static void sccnxp_start_tx(struct uart_port *port)
 	spin_lock_irqsave(&s->lock, flags);
 
 	/* Set direction to output */
-	if (s->flags & SCCNXP_HAVE_IO)
+	if (s->chip->flags & SCCNXP_HAVE_IO)
 		sccnxp_set_bit(port, DIR_OP, 1);
 
 	sccnxp_enable_irq(port, IMR_TXRDY);
@@ -483,7 +545,7 @@ static void sccnxp_set_mctrl(struct uart_port *port, unsigned int mctrl)
 	struct sccnxp_port *s = dev_get_drvdata(port->dev);
 	unsigned long flags;
 
-	if (!(s->flags & SCCNXP_HAVE_IO))
+	if (!(s->chip->flags & SCCNXP_HAVE_IO))
 		return;
 
 	spin_lock_irqsave(&s->lock, flags);
@@ -501,7 +563,7 @@ static unsigned int sccnxp_get_mctrl(struct uart_port *port)
 	struct sccnxp_port *s = dev_get_drvdata(port->dev);
 	unsigned int mctrl = TIOCM_DSR | TIOCM_CTS | TIOCM_CAR;
 
-	if (!(s->flags & SCCNXP_HAVE_IO))
+	if (!(s->chip->flags & SCCNXP_HAVE_IO))
 		return mctrl;
 
 	spin_lock_irqsave(&s->lock, flags);
@@ -617,7 +679,7 @@ static void sccnxp_set_termios(struct uart_port *port,
 
 	/* Setup baudrate */
 	baud = uart_get_baud_rate(port, termios, old, 50,
-				  (s->flags & SCCNXP_HAVE_MR0) ?
+				  (s->chip->flags & SCCNXP_HAVE_MR0) ?
 				  230400 : 38400);
 	baud = sccnxp_set_baud(port, baud);
 
@@ -641,7 +703,7 @@ static int sccnxp_startup(struct uart_port *port)
 
 	spin_lock_irqsave(&s->lock, flags);
 
-	if (s->flags & SCCNXP_HAVE_IO) {
+	if (s->chip->flags & SCCNXP_HAVE_IO) {
 		/* Outputs are controlled manually */
 		sccnxp_write(port, SCCNXP_OPCR_REG, 0);
 	}
@@ -681,7 +743,7 @@ static void sccnxp_shutdown(struct uart_port *port)
 	sccnxp_port_write(port, SCCNXP_CR_REG, CR_RX_DISABLE | CR_TX_DISABLE);
 
 	/* Leave direction to input */
-	if (s->flags & SCCNXP_HAVE_IO)
+	if (s->chip->flags & SCCNXP_HAVE_IO)
 		sccnxp_set_bit(port, DIR_OP, 0);
 
 	spin_unlock_irqrestore(&s->lock, flags);
@@ -691,7 +753,7 @@ static const char *sccnxp_type(struct uart_port *port)
 {
 	struct sccnxp_port *s = dev_get_drvdata(port->dev);
 
-	return (port->type == PORT_SC26XX) ? s->name : NULL;
+	return (port->type == PORT_SC26XX) ? s->chip->name : NULL;
 }
 
 static void sccnxp_release_port(struct uart_port *port)
@@ -778,19 +840,31 @@ static int sccnxp_console_setup(struct console *co, char *options)
 }
 #endif
 
+static const struct platform_device_id sccnxp_id_table[] = {
+	{ .name = "sc2681",	.driver_data = (kernel_ulong_t)&sc2681, },
+	{ .name = "sc2691",	.driver_data = (kernel_ulong_t)&sc2691, },
+	{ .name = "sc2692",	.driver_data = (kernel_ulong_t)&sc2692, },
+	{ .name = "sc2891",	.driver_data = (kernel_ulong_t)&sc2891, },
+	{ .name = "sc2892",	.driver_data = (kernel_ulong_t)&sc2892, },
+	{ .name = "sc28202",	.driver_data = (kernel_ulong_t)&sc28202, },
+	{ .name = "sc68681",	.driver_data = (kernel_ulong_t)&sc68681, },
+	{ .name = "sc68692",	.driver_data = (kernel_ulong_t)&sc68692, },
+	{ }
+};
+MODULE_DEVICE_TABLE(platform, sccnxp_id_table);
+
 static int sccnxp_probe(struct platform_device *pdev)
 {
 	struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	int chiptype = pdev->id_entry->driver_data;
 	struct sccnxp_pdata *pdata = dev_get_platdata(&pdev->dev);
-	int i, ret, fifosize, freq_min, freq_max;
+	int i, ret, uartclk;
 	struct sccnxp_port *s;
 	void __iomem *membase;
+	struct clk *clk;
 
-	if (!res) {
-		dev_err(&pdev->dev, "Missing memory resource data\n");
-		return -EADDRNOTAVAIL;
-	}
+	membase = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(membase))
+		return PTR_ERR(membase);
 
 	s = devm_kzalloc(&pdev->dev, sizeof(struct sccnxp_port), GFP_KERNEL);
 	if (!s) {
@@ -801,99 +875,38 @@ static int sccnxp_probe(struct platform_device *pdev)
 
 	spin_lock_init(&s->lock);
 
-	/* Individual chip settings */
-	switch (chiptype) {
-	case SCCNXP_TYPE_SC2681:
-		s->name		= "SC2681";
-		s->uart.nr	= 2;
-		s->freq_std	= 3686400;
-		s->addr_mask	= 0x0f;
-		s->flags	= SCCNXP_HAVE_IO;
-		fifosize	= 3;
-		freq_min	= 1000000;
-		freq_max	= 4000000;
-		break;
-	case SCCNXP_TYPE_SC2691:
-		s->name		= "SC2691";
-		s->uart.nr	= 1;
-		s->freq_std	= 3686400;
-		s->addr_mask	= 0x07;
-		s->flags	= 0;
-		fifosize	= 3;
-		freq_min	= 1000000;
-		freq_max	= 4000000;
-		break;
-	case SCCNXP_TYPE_SC2692:
-		s->name		= "SC2692";
-		s->uart.nr	= 2;
-		s->freq_std	= 3686400;
-		s->addr_mask	= 0x0f;
-		s->flags	= SCCNXP_HAVE_IO;
-		fifosize	= 3;
-		freq_min	= 1000000;
-		freq_max	= 4000000;
-		break;
-	case SCCNXP_TYPE_SC2891:
-		s->name		= "SC2891";
-		s->uart.nr	= 1;
-		s->freq_std	= 3686400;
-		s->addr_mask	= 0x0f;
-		s->flags	= SCCNXP_HAVE_IO | SCCNXP_HAVE_MR0;
-		fifosize	= 16;
-		freq_min	= 100000;
-		freq_max	= 8000000;
-		break;
-	case SCCNXP_TYPE_SC2892:
-		s->name		= "SC2892";
-		s->uart.nr	= 2;
-		s->freq_std	= 3686400;
-		s->addr_mask	= 0x0f;
-		s->flags	= SCCNXP_HAVE_IO | SCCNXP_HAVE_MR0;
-		fifosize	= 16;
-		freq_min	= 100000;
-		freq_max	= 8000000;
-		break;
-	case SCCNXP_TYPE_SC28202:
-		s->name		= "SC28202";
-		s->uart.nr	= 2;
-		s->freq_std	= 14745600;
-		s->addr_mask	= 0x7f;
-		s->flags	= SCCNXP_HAVE_IO | SCCNXP_HAVE_MR0;
-		fifosize	= 256;
-		freq_min	= 1000000;
-		freq_max	= 50000000;
-		break;
-	case SCCNXP_TYPE_SC68681:
-		s->name		= "SC68681";
-		s->uart.nr	= 2;
-		s->freq_std	= 3686400;
-		s->addr_mask	= 0x0f;
-		s->flags	= SCCNXP_HAVE_IO;
-		fifosize	= 3;
-		freq_min	= 1000000;
-		freq_max	= 4000000;
-		break;
-	case SCCNXP_TYPE_SC68692:
-		s->name		= "SC68692";
-		s->uart.nr	= 2;
-		s->freq_std	= 3686400;
-		s->addr_mask	= 0x0f;
-		s->flags	= SCCNXP_HAVE_IO;
-		fifosize	= 3;
-		freq_min	= 1000000;
-		freq_max	= 4000000;
-		break;
-	default:
-		dev_err(&pdev->dev, "Unsupported chip type %i\n", chiptype);
-		ret = -ENOTSUPP;
+	s->chip = (struct sccnxp_chip *)pdev->id_entry->driver_data;
+
+	s->regulator = devm_regulator_get(&pdev->dev, "vcc");
+	if (!IS_ERR(s->regulator)) {
+		ret = regulator_enable(s->regulator);
+		if (ret) {
+			dev_err(&pdev->dev,
+				"Failed to enable regulator: %i\n", ret);
+			return ret;
+		}
+	} else if (PTR_ERR(s->regulator) == -EPROBE_DEFER)
+		return -EPROBE_DEFER;
+
+	clk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(clk)) {
+		if (PTR_ERR(clk) == -EPROBE_DEFER) {
+			ret = -EPROBE_DEFER;
+			goto err_out;
+		}
+		dev_notice(&pdev->dev, "Using default clock frequency\n");
+		uartclk = s->chip->freq_std;
+	} else
+		uartclk = clk_get_rate(clk);
+
+	/* Check input frequency */
+	if ((uartclk < s->chip->freq_min) || (uartclk > s->chip->freq_max)) {
+		dev_err(&pdev->dev, "Frequency out of bounds\n");
+		ret = -EINVAL;
 		goto err_out;
 	}
 
-	if (!pdata) {
-		dev_warn(&pdev->dev,
-			 "No platform data supplied, using defaults\n");
-		s->pdata.frequency = s->freq_std;
-	} else
+	if (pdata)
 		memcpy(&s->pdata, pdata, sizeof(struct sccnxp_pdata));
 
 	if (s->pdata.poll_time_us) {
@@ -911,34 +924,11 @@ static int sccnxp_probe(struct platform_device *pdev)
 		}
 	}
 
-	/* Check input frequency */
-	if ((s->pdata.frequency < freq_min) ||
-	    (s->pdata.frequency > freq_max)) {
-		dev_err(&pdev->dev, "Frequency out of bounds\n");
-		ret = -EINVAL;
-		goto err_out;
-	}
-
-	s->regulator = devm_regulator_get(&pdev->dev, "VCC");
-	if (!IS_ERR(s->regulator)) {
-		ret = regulator_enable(s->regulator);
-		if (ret) {
-			dev_err(&pdev->dev,
-				"Failed to enable regulator: %i\n", ret);
-			return ret;
-		}
-	}
-
-	membase = devm_ioremap_resource(&pdev->dev, res);
-	if (IS_ERR(membase)) {
-		ret = PTR_ERR(membase);
-		goto err_out;
-	}
-
 	s->uart.owner		= THIS_MODULE;
 	s->uart.dev_name	= "ttySC";
 	s->uart.major		= SCCNXP_MAJOR;
 	s->uart.minor		= SCCNXP_MINOR;
+	s->uart.nr		= s->chip->nr;
 #ifdef CONFIG_SERIAL_SCCNXP_CONSOLE
 	s->uart.cons		= &s->console;
 	s->uart.cons->device	= uart_console_device;
@@ -960,17 +950,17 @@ static int sccnxp_probe(struct platform_device *pdev)
 		s->port[i].dev		= &pdev->dev;
 		s->port[i].irq		= s->irq;
 		s->port[i].type		= PORT_SC26XX;
-		s->port[i].fifosize	= fifosize;
+		s->port[i].fifosize	= s->chip->fifosize;
 		s->port[i].flags	= UPF_SKIP_TEST | UPF_FIXED_TYPE;
 		s->port[i].iotype	= UPIO_MEM;
 		s->port[i].mapbase	= res->start;
 		s->port[i].membase	= membase;
 		s->port[i].regshift	= s->pdata.reg_shift;
-		s->port[i].uartclk	= s->pdata.frequency;
+		s->port[i].uartclk	= uartclk;
 		s->port[i].ops		= &sccnxp_ops;
 		uart_add_one_port(&s->uart, &s->port[i]);
 		/* Set direction to input */
-		if (s->flags & SCCNXP_HAVE_IO)
+		if (s->chip->flags & SCCNXP_HAVE_IO)
 			sccnxp_set_bit(&s->port[i], DIR_OP, 0);
 	}
 
@@ -997,7 +987,8 @@ static int sccnxp_probe(struct platform_device *pdev)
 	}
 
 err_out:
-	platform_set_drvdata(pdev, NULL);
+	if (!IS_ERR(s->regulator))
+		return regulator_disable(s->regulator);
 
 	return ret;
 }
@@ -1016,7 +1007,6 @@ static int sccnxp_remove(struct platform_device *pdev)
 		uart_remove_one_port(&s->uart, &s->port[i]);
 
 	uart_unregister_driver(&s->uart);
-	platform_set_drvdata(pdev, NULL);
 
 	if (!IS_ERR(s->regulator))
 		return regulator_disable(s->regulator);
@@ -1024,19 +1014,6 @@ static int sccnxp_remove(struct platform_device *pdev)
 	return 0;
 }
 
-static const struct platform_device_id sccnxp_id_table[] = {
-	{ "sc2681",	SCCNXP_TYPE_SC2681 },
-	{ "sc2691",	SCCNXP_TYPE_SC2691 },
-	{ "sc2692",	SCCNXP_TYPE_SC2692 },
-	{ "sc2891",	SCCNXP_TYPE_SC2891 },
-	{ "sc2892",	SCCNXP_TYPE_SC2892 },
-	{ "sc28202",	SCCNXP_TYPE_SC28202 },
-	{ "sc68681",	SCCNXP_TYPE_SC68681 },
-	{ "sc68692",	SCCNXP_TYPE_SC68692 },
-	{ },
-};
-MODULE_DEVICE_TABLE(platform, sccnxp_id_table);
-
 static struct platform_driver sccnxp_uart_driver = {
 	.driver = {
 		.name	= SCCNXP_NAME,
diff --git a/drivers/tty/serial/serial-tegra.c b/drivers/tty/serial/serial-tegra.c
index ee7c8123c37..d0d972f7e43 100644
--- a/drivers/tty/serial/serial-tegra.c
+++ b/drivers/tty/serial/serial-tegra.c
@@ -571,7 +571,9 @@ static void tegra_uart_rx_dma_complete(void *args)
 
 	tegra_uart_handle_rx_pio(tup, port);
 	if (tty) {
+		spin_unlock_irqrestore(&u->lock, flags);
 		tty_flip_buffer_push(port);
+		spin_lock_irqsave(&u->lock, flags);
 		tty_kref_put(tty);
 	}
 	tegra_uart_start_rx_dma(tup);
@@ -583,11 +585,13 @@ static void tegra_uart_rx_dma_complete(void *args)
 	spin_unlock_irqrestore(&u->lock, flags);
 }
 
-static void tegra_uart_handle_rx_dma(struct tegra_uart_port *tup)
+static void tegra_uart_handle_rx_dma(struct tegra_uart_port *tup,
+		unsigned long *flags)
 {
 	struct dma_tx_state state;
 	struct tty_struct *tty = tty_port_tty_get(&tup->uport.state->port);
 	struct tty_port *port = &tup->uport.state->port;
+	struct uart_port *u = &tup->uport;
 	int count;
 
 	/* Deactivate flow control to stop sender */
@@ -604,7 +608,9 @@ static void tegra_uart_handle_rx_dma(struct tegra_uart_port *tup)
 
 	tegra_uart_handle_rx_pio(tup, port);
 	if (tty) {
+		spin_unlock_irqrestore(&u->lock, *flags);
 		tty_flip_buffer_push(port);
+		spin_lock_irqsave(&u->lock, *flags);
 		tty_kref_put(tty);
 	}
 	tegra_uart_start_rx_dma(tup);
@@ -671,7 +677,7 @@ static irqreturn_t tegra_uart_isr(int irq, void *data)
 		iir = tegra_uart_read(tup, UART_IIR);
 		if (iir & UART_IIR_NO_INT) {
 			if (is_rx_int) {
-				tegra_uart_handle_rx_dma(tup);
+				tegra_uart_handle_rx_dma(tup, &flags);
 				if (tup->rx_in_progress) {
 					ier = tup->ier_shadow;
 					ier |= (UART_IER_RLSI | UART_IER_RTOIE |
@@ -1206,7 +1212,7 @@ static struct uart_driver tegra_uart_driver = {
 	.owner		= THIS_MODULE,
 	.driver_name	= "tegra_hsuart",
 	.dev_name	= "ttyTHS",
-	.cons		= 0,
+	.cons		= NULL,
 	.nr		= TEGRA_UART_MAXIMUM,
 };
 
@@ -1237,13 +1243,13 @@ static int tegra_uart_parse_dt(struct platform_device *pdev,
 	return 0;
 }
 
-struct tegra_uart_chip_data tegra20_uart_chip_data = {
+static struct tegra_uart_chip_data tegra20_uart_chip_data = {
 	.tx_fifo_full_status		= false,
 	.allow_txfifo_reset_fifo_mode	= true,
 	.support_clk_src_div		= false,
 };
 
-struct tegra_uart_chip_data tegra30_uart_chip_data = {
+static struct tegra_uart_chip_data tegra30_uart_chip_data = {
 	.tx_fifo_full_status		= true,
 	.allow_txfifo_reset_fifo_mode	= false,
 	.support_clk_src_div		= true,
diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c
index 28cdd282913..0f02351c923 100644
--- a/drivers/tty/serial/serial_core.c
+++ b/drivers/tty/serial/serial_core.c
@@ -2095,12 +2095,12 @@ uart_report_port(struct uart_driver *drv, struct uart_port *port)
 		break;
 	}
 
-	printk(KERN_INFO "%s%s%s%d at %s (irq = %d) is a %s\n",
+	printk(KERN_INFO "%s%s%s%d at %s (irq = %d, base_baud = %d) is a %s\n",
 	       port->dev ? dev_name(port->dev) : "",
 	       port->dev ? ": " : "",
 	       drv->dev_name,
 	       drv->tty_driver->name_base + port->line,
-	       address, port->irq, uart_type(port));
+	       address, port->irq, port->uartclk / 16, uart_type(port));
 }
 
 static void
diff --git a/drivers/tty/serial/serial_txx9.c b/drivers/tty/serial/serial_txx9.c
index fe48a0c2b4c..440a962412d 100644
--- a/drivers/tty/serial/serial_txx9.c
+++ b/drivers/tty/serial/serial_txx9.c
@@ -1097,7 +1097,7 @@ static void serial_txx9_unregister_port(int line)
  */
 static int serial_txx9_probe(struct platform_device *dev)
 {
-	struct uart_port *p = dev->dev.platform_data;
+	struct uart_port *p = dev_get_platdata(&dev->dev);
 	struct uart_port port;
 	int ret, i;
 
diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c
index 7477e0ea5cd..537750261aa 100644
--- a/drivers/tty/serial/sh-sci.c
+++ b/drivers/tty/serial/sh-sci.c
@@ -2380,7 +2380,7 @@ static char early_serial_buf[32];
 
 static int sci_probe_earlyprintk(struct platform_device *pdev)
 {
-	struct plat_sci_port *cfg = pdev->dev.platform_data;
+	struct plat_sci_port *cfg = dev_get_platdata(&pdev->dev);
 
 	if (early_serial_console.data)
 		return -EEXIST;
@@ -2469,7 +2469,7 @@ static int sci_probe_single(struct platform_device *dev,
 
 static int sci_probe(struct platform_device *dev)
 {
-	struct plat_sci_port *p = dev->dev.platform_data;
+	struct plat_sci_port *p = dev_get_platdata(&dev->dev);
 	struct sci_port *sp = &sci_ports[dev->id];
 	int ret;
 
diff --git a/drivers/tty/serial/sirfsoc_uart.c b/drivers/tty/serial/sirfsoc_uart.c
index 1fd564b8194..61c1ad03db5 100644
--- a/drivers/tty/serial/sirfsoc_uart.c
+++ b/drivers/tty/serial/sirfsoc_uart.c
@@ -20,9 +20,13 @@
 #include <linux/of.h>
 #include <linux/slab.h>
 #include <linux/io.h>
+#include <linux/of_gpio.h>
+#include <linux/dmaengine.h>
+#include <linux/dma-direction.h>
+#include <linux/dma-mapping.h>
+#include <linux/sirfsoc_dma.h>
 #include <asm/irq.h>
 #include <asm/mach/irq.h>
-#include <linux/pinctrl/consumer.h>
 
 #include "sirfsoc_uart.h"
 
@@ -32,6 +36,9 @@ static unsigned int
 sirfsoc_uart_pio_rx_chars(struct uart_port *port, unsigned int max_rx_count);
 static struct uart_driver sirfsoc_uart_drv;
 
+static void sirfsoc_uart_tx_dma_complete_callback(void *param);
+static void sirfsoc_uart_start_next_rx_dma(struct uart_port *port);
+static void sirfsoc_uart_rx_dma_complete_callback(void *param);
 static const struct sirfsoc_baudrate_to_regv baudrate_to_regv[] = {
 	{4000000, 2359296},
 	{3500000, 1310721},
@@ -89,6 +96,13 @@ static struct sirfsoc_uart_port sirfsoc_uart_ports[SIRFSOC_UART_NR] = {
 			.line		= 4,
 		},
 	},
+	[5] = {
+		.port = {
+			.iotype		= UPIO_MEM,
+			.flags		= UPF_BOOT_AUTOCONF,
+			.line		= 5,
+		},
+	},
 };
 
 static inline struct sirfsoc_uart_port *to_sirfport(struct uart_port *port)
@@ -99,21 +113,28 @@ static inline struct sirfsoc_uart_port *to_sirfport(struct uart_port *port)
 static inline unsigned int sirfsoc_uart_tx_empty(struct uart_port *port)
 {
 	unsigned long reg;
-	reg = rd_regl(port, SIRFUART_TX_FIFO_STATUS);
-	if (reg & SIRFUART_FIFOEMPTY_MASK(port))
-		return TIOCSER_TEMT;
-	else
-		return 0;
+	struct sirfsoc_uart_port *sirfport = to_sirfport(port);
+	struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
+	struct sirfsoc_fifo_status *ufifo_st = &sirfport->uart_reg->fifo_status;
+	reg = rd_regl(port, ureg->sirfsoc_tx_fifo_status);
+
+	return (reg & ufifo_st->ff_empty(port->line)) ? TIOCSER_TEMT : 0;
 }
 
 static unsigned int sirfsoc_uart_get_mctrl(struct uart_port *port)
 {
 	struct sirfsoc_uart_port *sirfport = to_sirfport(port);
-	if (!(sirfport->ms_enabled)) {
+	struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
+	if (!sirfport->hw_flow_ctrl || !sirfport->ms_enabled)
 		goto cts_asserted;
-	} else if (sirfport->hw_flow_ctrl) {
-		if (!(rd_regl(port, SIRFUART_AFC_CTRL) &
-						SIRFUART_CTS_IN_STATUS))
+	if (sirfport->uart_reg->uart_type == SIRF_REAL_UART) {
+		if (!(rd_regl(port, ureg->sirfsoc_afc_ctrl) &
+						SIRFUART_AFC_CTS_STATUS))
+			goto cts_asserted;
+		else
+			goto cts_deasserted;
+	} else {
+		if (!gpio_get_value(sirfport->cts_gpio))
 			goto cts_asserted;
 		else
 			goto cts_deasserted;
@@ -127,89 +148,276 @@ cts_asserted:
 static void sirfsoc_uart_set_mctrl(struct uart_port *port, unsigned int mctrl)
 {
 	struct sirfsoc_uart_port *sirfport = to_sirfport(port);
+	struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
 	unsigned int assert = mctrl & TIOCM_RTS;
 	unsigned int val = assert ? SIRFUART_AFC_CTRL_RX_THD : 0x0;
 	unsigned int current_val;
-	if (sirfport->hw_flow_ctrl) {
-		current_val = rd_regl(port, SIRFUART_AFC_CTRL) & ~0xFF;
+
+	if (!sirfport->hw_flow_ctrl || !sirfport->ms_enabled)
+		return;
+	if (sirfport->uart_reg->uart_type == SIRF_REAL_UART) {
+		current_val = rd_regl(port, ureg->sirfsoc_afc_ctrl) & ~0xFF;
 		val |= current_val;
-		wr_regl(port, SIRFUART_AFC_CTRL, val);
+		wr_regl(port, ureg->sirfsoc_afc_ctrl, val);
+	} else {
+		if (!val)
+			gpio_set_value(sirfport->rts_gpio, 1);
+		else
+			gpio_set_value(sirfport->rts_gpio, 0);
 	}
 }
 
 static void sirfsoc_uart_stop_tx(struct uart_port *port)
 {
-	unsigned int regv;
-	regv = rd_regl(port, SIRFUART_INT_EN);
-	wr_regl(port, SIRFUART_INT_EN, regv & ~SIRFUART_TX_INT_EN);
+	struct sirfsoc_uart_port *sirfport = to_sirfport(port);
+	struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
+	struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
+
+	if (IS_DMA_CHAN_VALID(sirfport->tx_dma_no)) {
+		if (sirfport->tx_dma_state == TX_DMA_RUNNING) {
+			dmaengine_pause(sirfport->tx_dma_chan);
+			sirfport->tx_dma_state = TX_DMA_PAUSE;
+		} else {
+			if (!sirfport->is_marco)
+				wr_regl(port, ureg->sirfsoc_int_en_reg,
+				rd_regl(port, ureg->sirfsoc_int_en_reg) &
+				~uint_en->sirfsoc_txfifo_empty_en);
+			else
+				wr_regl(port, SIRFUART_INT_EN_CLR,
+				uint_en->sirfsoc_txfifo_empty_en);
+		}
+	} else {
+		if (!sirfport->is_marco)
+			wr_regl(port, ureg->sirfsoc_int_en_reg,
+				rd_regl(port, ureg->sirfsoc_int_en_reg) &
+				~uint_en->sirfsoc_txfifo_empty_en);
+		else
+			wr_regl(port, SIRFUART_INT_EN_CLR,
+				uint_en->sirfsoc_txfifo_empty_en);
+	}
 }
 
-void sirfsoc_uart_start_tx(struct uart_port *port)
+static void sirfsoc_uart_tx_with_dma(struct sirfsoc_uart_port *sirfport)
+{
+	struct uart_port *port = &sirfport->port;
+	struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
+	struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
+	struct circ_buf *xmit = &port->state->xmit;
+	unsigned long tran_size;
+	unsigned long tran_start;
+	unsigned long pio_tx_size;
+
+	tran_size = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
+	tran_start = (unsigned long)(xmit->buf + xmit->tail);
+	if (uart_circ_empty(xmit) || uart_tx_stopped(port) ||
+			!tran_size)
+		return;
+	if (sirfport->tx_dma_state == TX_DMA_PAUSE) {
+		dmaengine_resume(sirfport->tx_dma_chan);
+		return;
+	}
+	if (sirfport->tx_dma_state == TX_DMA_RUNNING)
+		return;
+	if (!sirfport->is_marco)
+		wr_regl(port, ureg->sirfsoc_int_en_reg,
+				rd_regl(port, ureg->sirfsoc_int_en_reg)&
+				~(uint_en->sirfsoc_txfifo_empty_en));
+	else
+		wr_regl(port, SIRFUART_INT_EN_CLR,
+				uint_en->sirfsoc_txfifo_empty_en);
+	/*
+	 * DMA requires buffer address and buffer length are both aligned with
+	 * 4 bytes, so we use PIO for
+	 * 1. if address is not aligned with 4bytes, use PIO for the first 1~3
+	 * bytes, and move to DMA for the left part aligned with 4bytes
+	 * 2. if buffer length is not aligned with 4bytes, use DMA for aligned
+	 * part first, move to PIO for the left 1~3 bytes
+	 */
+	if (tran_size < 4 || BYTES_TO_ALIGN(tran_start)) {
+		wr_regl(port, ureg->sirfsoc_tx_fifo_op, SIRFUART_FIFO_STOP);
+		wr_regl(port, ureg->sirfsoc_tx_dma_io_ctrl,
+			rd_regl(port, ureg->sirfsoc_tx_dma_io_ctrl)|
+			SIRFUART_IO_MODE);
+		if (BYTES_TO_ALIGN(tran_start)) {
+			pio_tx_size = sirfsoc_uart_pio_tx_chars(sirfport,
+				BYTES_TO_ALIGN(tran_start));
+			tran_size -= pio_tx_size;
+		}
+		if (tran_size < 4)
+			sirfsoc_uart_pio_tx_chars(sirfport, tran_size);
+		if (!sirfport->is_marco)
+			wr_regl(port, ureg->sirfsoc_int_en_reg,
+				rd_regl(port, ureg->sirfsoc_int_en_reg)|
+				uint_en->sirfsoc_txfifo_empty_en);
+		else
+			wr_regl(port, ureg->sirfsoc_int_en_reg,
+				uint_en->sirfsoc_txfifo_empty_en);
+		wr_regl(port, ureg->sirfsoc_tx_fifo_op, SIRFUART_FIFO_START);
+	} else {
+		/* tx transfer mode switch into dma mode */
+		wr_regl(port, ureg->sirfsoc_tx_fifo_op, SIRFUART_FIFO_STOP);
+		wr_regl(port, ureg->sirfsoc_tx_dma_io_ctrl,
+			rd_regl(port, ureg->sirfsoc_tx_dma_io_ctrl)&
+			~SIRFUART_IO_MODE);
+		wr_regl(port, ureg->sirfsoc_tx_fifo_op, SIRFUART_FIFO_START);
+		tran_size &= ~(0x3);
+
+		sirfport->tx_dma_addr = dma_map_single(port->dev,
+			xmit->buf + xmit->tail,
+			tran_size, DMA_TO_DEVICE);
+		sirfport->tx_dma_desc = dmaengine_prep_slave_single(
+			sirfport->tx_dma_chan, sirfport->tx_dma_addr,
+			tran_size, DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT);
+		if (!sirfport->tx_dma_desc) {
+			dev_err(port->dev, "DMA prep slave single fail\n");
+			return;
+		}
+		sirfport->tx_dma_desc->callback =
+			sirfsoc_uart_tx_dma_complete_callback;
+		sirfport->tx_dma_desc->callback_param = (void *)sirfport;
+		sirfport->transfer_size = tran_size;
+
+		dmaengine_submit(sirfport->tx_dma_desc);
+		dma_async_issue_pending(sirfport->tx_dma_chan);
+		sirfport->tx_dma_state = TX_DMA_RUNNING;
+	}
+}
+
+static void sirfsoc_uart_start_tx(struct uart_port *port)
 {
 	struct sirfsoc_uart_port *sirfport = to_sirfport(port);
-	unsigned long regv;
-	sirfsoc_uart_pio_tx_chars(sirfport, 1);
-	wr_regl(port, SIRFUART_TX_FIFO_OP, SIRFUART_TX_FIFO_START);
-	regv = rd_regl(port, SIRFUART_INT_EN);
-	wr_regl(port, SIRFUART_INT_EN, regv | SIRFUART_TX_INT_EN);
+	struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
+	struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
+	if (IS_DMA_CHAN_VALID(sirfport->tx_dma_no))
+		sirfsoc_uart_tx_with_dma(sirfport);
+	else {
+		sirfsoc_uart_pio_tx_chars(sirfport, 1);
+		wr_regl(port, ureg->sirfsoc_tx_fifo_op, SIRFUART_FIFO_START);
+		if (!sirfport->is_marco)
+			wr_regl(port, ureg->sirfsoc_int_en_reg,
+					rd_regl(port, ureg->sirfsoc_int_en_reg)|
+					uint_en->sirfsoc_txfifo_empty_en);
+		else
+			wr_regl(port, ureg->sirfsoc_int_en_reg,
+					uint_en->sirfsoc_txfifo_empty_en);
+	}
 }
 
 static void sirfsoc_uart_stop_rx(struct uart_port *port)
 {
-	unsigned long regv;
-	wr_regl(port, SIRFUART_RX_FIFO_OP, 0);
-	regv = rd_regl(port, SIRFUART_INT_EN);
-	wr_regl(port, SIRFUART_INT_EN, regv & ~SIRFUART_RX_IO_INT_EN);
+	struct sirfsoc_uart_port *sirfport = to_sirfport(port);
+	struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
+	struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
+
+	wr_regl(port, ureg->sirfsoc_rx_fifo_op, 0);
+	if (IS_DMA_CHAN_VALID(sirfport->rx_dma_no)) {
+		if (!sirfport->is_marco)
+			wr_regl(port, ureg->sirfsoc_int_en_reg,
+				rd_regl(port, ureg->sirfsoc_int_en_reg) &
+				~(SIRFUART_RX_DMA_INT_EN(port, uint_en) |
+				uint_en->sirfsoc_rx_done_en));
+		else
+			wr_regl(port, SIRFUART_INT_EN_CLR,
+					SIRFUART_RX_DMA_INT_EN(port, uint_en)|
+					uint_en->sirfsoc_rx_done_en);
+		dmaengine_terminate_all(sirfport->rx_dma_chan);
+	} else {
+		if (!sirfport->is_marco)
+			wr_regl(port, ureg->sirfsoc_int_en_reg,
+				rd_regl(port, ureg->sirfsoc_int_en_reg)&
+				~(SIRFUART_RX_IO_INT_EN(port, uint_en)));
+		else
+			wr_regl(port, SIRFUART_INT_EN_CLR,
+					SIRFUART_RX_IO_INT_EN(port, uint_en));
+	}
 }
 
 static void sirfsoc_uart_disable_ms(struct uart_port *port)
 {
 	struct sirfsoc_uart_port *sirfport = to_sirfport(port);
-	unsigned long reg;
-	sirfport->ms_enabled = 0;
+	struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
+	struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
+
 	if (!sirfport->hw_flow_ctrl)
 		return;
-	reg = rd_regl(port, SIRFUART_AFC_CTRL);
-	wr_regl(port, SIRFUART_AFC_CTRL, reg & ~0x3FF);
-	reg = rd_regl(port, SIRFUART_INT_EN);
-	wr_regl(port, SIRFUART_INT_EN, reg & ~SIRFUART_CTS_INT_EN);
+	sirfport->ms_enabled = false;
+	if (sirfport->uart_reg->uart_type == SIRF_REAL_UART) {
+		wr_regl(port, ureg->sirfsoc_afc_ctrl,
+				rd_regl(port, ureg->sirfsoc_afc_ctrl) & ~0x3FF);
+		if (!sirfport->is_marco)
+			wr_regl(port, ureg->sirfsoc_int_en_reg,
+					rd_regl(port, ureg->sirfsoc_int_en_reg)&
+					~uint_en->sirfsoc_cts_en);
+		else
+			wr_regl(port, SIRFUART_INT_EN_CLR,
+					uint_en->sirfsoc_cts_en);
+	} else
+		disable_irq(gpio_to_irq(sirfport->cts_gpio));
+}
+
+static irqreturn_t sirfsoc_uart_usp_cts_handler(int irq, void *dev_id)
+{
+	struct sirfsoc_uart_port *sirfport = (struct sirfsoc_uart_port *)dev_id;
+	struct uart_port *port = &sirfport->port;
+	if (gpio_is_valid(sirfport->cts_gpio) && sirfport->ms_enabled)
+		uart_handle_cts_change(port,
+				!gpio_get_value(sirfport->cts_gpio));
+	return IRQ_HANDLED;
 }
 
 static void sirfsoc_uart_enable_ms(struct uart_port *port)
 {
 	struct sirfsoc_uart_port *sirfport = to_sirfport(port);
-	unsigned long reg;
-	unsigned long flg;
+	struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
+	struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
+
 	if (!sirfport->hw_flow_ctrl)
 		return;
-	flg = SIRFUART_AFC_RX_EN | SIRFUART_AFC_TX_EN;
-	reg = rd_regl(port, SIRFUART_AFC_CTRL);
-	wr_regl(port, SIRFUART_AFC_CTRL, reg | flg);
-	reg = rd_regl(port, SIRFUART_INT_EN);
-	wr_regl(port, SIRFUART_INT_EN, reg | SIRFUART_CTS_INT_EN);
-	uart_handle_cts_change(port,
-		!(rd_regl(port, SIRFUART_AFC_CTRL) & SIRFUART_CTS_IN_STATUS));
-	sirfport->ms_enabled = 1;
+	sirfport->ms_enabled = true;
+	if (sirfport->uart_reg->uart_type == SIRF_REAL_UART) {
+		wr_regl(port, ureg->sirfsoc_afc_ctrl,
+				rd_regl(port, ureg->sirfsoc_afc_ctrl) |
+				SIRFUART_AFC_TX_EN | SIRFUART_AFC_RX_EN);
+		if (!sirfport->is_marco)
+			wr_regl(port, ureg->sirfsoc_int_en_reg,
+					rd_regl(port, ureg->sirfsoc_int_en_reg)
+					| uint_en->sirfsoc_cts_en);
+		else
+			wr_regl(port, ureg->sirfsoc_int_en_reg,
+					uint_en->sirfsoc_cts_en);
+	} else
+		enable_irq(gpio_to_irq(sirfport->cts_gpio));
 }
 
 static void sirfsoc_uart_break_ctl(struct uart_port *port, int break_state)
 {
-	unsigned long ulcon = rd_regl(port, SIRFUART_LINE_CTRL);
-	if (break_state)
-		ulcon |= SIRFUART_SET_BREAK;
-	else
-		ulcon &= ~SIRFUART_SET_BREAK;
-	wr_regl(port, SIRFUART_LINE_CTRL, ulcon);
+	struct sirfsoc_uart_port *sirfport = to_sirfport(port);
+	struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
+	if (sirfport->uart_reg->uart_type == SIRF_REAL_UART) {
+		unsigned long ulcon = rd_regl(port, ureg->sirfsoc_line_ctrl);
+		if (break_state)
+			ulcon |= SIRFUART_SET_BREAK;
+		else
+			ulcon &= ~SIRFUART_SET_BREAK;
+		wr_regl(port, ureg->sirfsoc_line_ctrl, ulcon);
+	}
 }
 
 static unsigned int
 sirfsoc_uart_pio_rx_chars(struct uart_port *port, unsigned int max_rx_count)
 {
+	struct sirfsoc_uart_port *sirfport = to_sirfport(port);
+	struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
+	struct sirfsoc_fifo_status *ufifo_st = &sirfport->uart_reg->fifo_status;
 	unsigned int ch, rx_count = 0;
-
-	while (!(rd_regl(port, SIRFUART_RX_FIFO_STATUS) &
-					SIRFUART_FIFOEMPTY_MASK(port))) {
-		ch = rd_regl(port, SIRFUART_RX_FIFO_DATA) | SIRFUART_DUMMY_READ;
+	struct tty_struct *tty;
+	tty = tty_port_tty_get(&port->state->port);
+	if (!tty)
+		return -ENODEV;
+	while (!(rd_regl(port, ureg->sirfsoc_rx_fifo_status) &
+					ufifo_st->ff_empty(port->line))) {
+		ch = rd_regl(port, ureg->sirfsoc_rx_fifo_data) |
+			SIRFUART_DUMMY_READ;
 		if (unlikely(uart_handle_sysrq_char(port, ch)))
 			continue;
 		uart_insert_char(port, 0, 0, ch, TTY_NORMAL);
@@ -218,8 +426,12 @@ sirfsoc_uart_pio_rx_chars(struct uart_port *port, unsigned int max_rx_count)
 			break;
 	}
 
+	sirfport->rx_io_count += rx_count;
 	port->icount.rx += rx_count;
+
+	spin_unlock(&port->lock);
 	tty_flip_buffer_push(&port->state->port);
+	spin_lock(&port->lock);
 
 	return rx_count;
 }
@@ -228,13 +440,16 @@ static unsigned int
 sirfsoc_uart_pio_tx_chars(struct sirfsoc_uart_port *sirfport, int count)
 {
 	struct uart_port *port = &sirfport->port;
+	struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
+	struct sirfsoc_fifo_status *ufifo_st = &sirfport->uart_reg->fifo_status;
 	struct circ_buf *xmit = &port->state->xmit;
 	unsigned int num_tx = 0;
 	while (!uart_circ_empty(xmit) &&
-		!(rd_regl(port, SIRFUART_TX_FIFO_STATUS) &
-					SIRFUART_FIFOFULL_MASK(port)) &&
+		!(rd_regl(port, ureg->sirfsoc_tx_fifo_status) &
+					ufifo_st->ff_full(port->line)) &&
 		count--) {
-		wr_regl(port, SIRFUART_TX_FIFO_DATA, xmit->buf[xmit->tail]);
+		wr_regl(port, ureg->sirfsoc_tx_fifo_data,
+				xmit->buf[xmit->tail]);
 		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 		port->icount.tx++;
 		num_tx++;
@@ -244,6 +459,166 @@ sirfsoc_uart_pio_tx_chars(struct sirfsoc_uart_port *sirfport, int count)
 	return num_tx;
 }
 
+static void sirfsoc_uart_tx_dma_complete_callback(void *param)
+{
+	struct sirfsoc_uart_port *sirfport = (struct sirfsoc_uart_port *)param;
+	struct uart_port *port = &sirfport->port;
+	struct circ_buf *xmit = &port->state->xmit;
+	unsigned long flags;
+
+	xmit->tail = (xmit->tail + sirfport->transfer_size) &
+				(UART_XMIT_SIZE - 1);
+	port->icount.tx += sirfport->transfer_size;
+	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+		uart_write_wakeup(port);
+	if (sirfport->tx_dma_addr)
+		dma_unmap_single(port->dev, sirfport->tx_dma_addr,
+				sirfport->transfer_size, DMA_TO_DEVICE);
+	spin_lock_irqsave(&sirfport->tx_lock, flags);
+	sirfport->tx_dma_state = TX_DMA_IDLE;
+	sirfsoc_uart_tx_with_dma(sirfport);
+	spin_unlock_irqrestore(&sirfport->tx_lock, flags);
+}
+
+static void sirfsoc_uart_insert_rx_buf_to_tty(
+		struct sirfsoc_uart_port *sirfport, int count)
+{
+	struct uart_port *port = &sirfport->port;
+	struct tty_port *tport = &port->state->port;
+	int inserted;
+
+	inserted = tty_insert_flip_string(tport,
+		sirfport->rx_dma_items[sirfport->rx_completed].xmit.buf, count);
+	port->icount.rx += inserted;
+	tty_flip_buffer_push(tport);
+}
+
+static void sirfsoc_rx_submit_one_dma_desc(struct uart_port *port, int index)
+{
+	struct sirfsoc_uart_port *sirfport = to_sirfport(port);
+
+	sirfport->rx_dma_items[index].xmit.tail =
+		sirfport->rx_dma_items[index].xmit.head = 0;
+	sirfport->rx_dma_items[index].desc =
+		dmaengine_prep_slave_single(sirfport->rx_dma_chan,
+		sirfport->rx_dma_items[index].dma_addr, SIRFSOC_RX_DMA_BUF_SIZE,
+		DMA_DEV_TO_MEM, DMA_PREP_INTERRUPT);
+	if (!sirfport->rx_dma_items[index].desc) {
+		dev_err(port->dev, "DMA slave single fail\n");
+		return;
+	}
+	sirfport->rx_dma_items[index].desc->callback =
+		sirfsoc_uart_rx_dma_complete_callback;
+	sirfport->rx_dma_items[index].desc->callback_param = sirfport;
+	sirfport->rx_dma_items[index].cookie =
+		dmaengine_submit(sirfport->rx_dma_items[index].desc);
+	dma_async_issue_pending(sirfport->rx_dma_chan);
+}
+
+static void sirfsoc_rx_tmo_process_tl(unsigned long param)
+{
+	struct sirfsoc_uart_port *sirfport = (struct sirfsoc_uart_port *)param;
+	struct uart_port *port = &sirfport->port;
+	struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
+	struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
+	struct sirfsoc_int_status *uint_st = &sirfport->uart_reg->uart_int_st;
+	unsigned int count;
+	unsigned long flags;
+
+	spin_lock_irqsave(&sirfport->rx_lock, flags);
+	while (sirfport->rx_completed != sirfport->rx_issued) {
+		sirfsoc_uart_insert_rx_buf_to_tty(sirfport,
+					SIRFSOC_RX_DMA_BUF_SIZE);
+		sirfsoc_rx_submit_one_dma_desc(port, sirfport->rx_completed++);
+		sirfport->rx_completed %= SIRFSOC_RX_LOOP_BUF_CNT;
+	}
+	count = CIRC_CNT(sirfport->rx_dma_items[sirfport->rx_issued].xmit.head,
+		sirfport->rx_dma_items[sirfport->rx_issued].xmit.tail,
+		SIRFSOC_RX_DMA_BUF_SIZE);
+	if (count > 0)
+		sirfsoc_uart_insert_rx_buf_to_tty(sirfport, count);
+	wr_regl(port, ureg->sirfsoc_rx_dma_io_ctrl,
+			rd_regl(port, ureg->sirfsoc_rx_dma_io_ctrl) |
+			SIRFUART_IO_MODE);
+	sirfsoc_uart_pio_rx_chars(port, 4 - sirfport->rx_io_count);
+	spin_unlock_irqrestore(&sirfport->rx_lock, flags);
+	if (sirfport->rx_io_count == 4) {
+		spin_lock_irqsave(&sirfport->rx_lock, flags);
+		sirfport->rx_io_count = 0;
+		wr_regl(port, ureg->sirfsoc_int_st_reg,
+				uint_st->sirfsoc_rx_done);
+		if (!sirfport->is_marco)
+			wr_regl(port, ureg->sirfsoc_int_en_reg,
+				rd_regl(port, ureg->sirfsoc_int_en_reg) &
+				~(uint_en->sirfsoc_rx_done_en));
+		else
+			wr_regl(port, SIRFUART_INT_EN_CLR,
+					uint_en->sirfsoc_rx_done_en);
+		spin_unlock_irqrestore(&sirfport->rx_lock, flags);
+
+		sirfsoc_uart_start_next_rx_dma(port);
+	} else {
+		spin_lock_irqsave(&sirfport->rx_lock, flags);
+		wr_regl(port, ureg->sirfsoc_int_st_reg,
+				uint_st->sirfsoc_rx_done);
+		if (!sirfport->is_marco)
+			wr_regl(port, ureg->sirfsoc_int_en_reg,
+				rd_regl(port, ureg->sirfsoc_int_en_reg) |
+				(uint_en->sirfsoc_rx_done_en));
+		else
+			wr_regl(port, ureg->sirfsoc_int_en_reg,
+					uint_en->sirfsoc_rx_done_en);
+		spin_unlock_irqrestore(&sirfport->rx_lock, flags);
+	}
+}
+
+static void sirfsoc_uart_handle_rx_tmo(struct sirfsoc_uart_port *sirfport)
+{
+	struct uart_port *port = &sirfport->port;
+	struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
+	struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
+	struct dma_tx_state tx_state;
+	spin_lock(&sirfport->rx_lock);
+
+	dmaengine_tx_status(sirfport->rx_dma_chan,
+		sirfport->rx_dma_items[sirfport->rx_issued].cookie, &tx_state);
+	dmaengine_terminate_all(sirfport->rx_dma_chan);
+	sirfport->rx_dma_items[sirfport->rx_issued].xmit.head =
+		SIRFSOC_RX_DMA_BUF_SIZE - tx_state.residue;
+	if (!sirfport->is_marco)
+		wr_regl(port, ureg->sirfsoc_int_en_reg,
+			rd_regl(port, ureg->sirfsoc_int_en_reg) &
+			~(uint_en->sirfsoc_rx_timeout_en));
+	else
+		wr_regl(port, SIRFUART_INT_EN_CLR,
+				uint_en->sirfsoc_rx_timeout_en);
+	spin_unlock(&sirfport->rx_lock);
+	tasklet_schedule(&sirfport->rx_tmo_process_tasklet);
+}
+
+static void sirfsoc_uart_handle_rx_done(struct sirfsoc_uart_port *sirfport)
+{
+	struct uart_port *port = &sirfport->port;
+	struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
+	struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
+	struct sirfsoc_int_status *uint_st = &sirfport->uart_reg->uart_int_st;
+
+	sirfsoc_uart_pio_rx_chars(port, 4 - sirfport->rx_io_count);
+	if (sirfport->rx_io_count == 4) {
+		sirfport->rx_io_count = 0;
+		if (!sirfport->is_marco)
+			wr_regl(port, ureg->sirfsoc_int_en_reg,
+				rd_regl(port, ureg->sirfsoc_int_en_reg) &
+				~(uint_en->sirfsoc_rx_done_en));
+		else
+			wr_regl(port, SIRFUART_INT_EN_CLR,
+					uint_en->sirfsoc_rx_done_en);
+		wr_regl(port, ureg->sirfsoc_int_st_reg,
+				uint_st->sirfsoc_rx_timeout);
+		sirfsoc_uart_start_next_rx_dma(port);
+	}
+}
+
 static irqreturn_t sirfsoc_uart_isr(int irq, void *dev_id)
 {
 	unsigned long intr_status;
@@ -251,79 +626,191 @@ static irqreturn_t sirfsoc_uart_isr(int irq, void *dev_id)
 	unsigned long flag = TTY_NORMAL;
 	struct sirfsoc_uart_port *sirfport = (struct sirfsoc_uart_port *)dev_id;
 	struct uart_port *port = &sirfport->port;
+	struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
+	struct sirfsoc_fifo_status *ufifo_st = &sirfport->uart_reg->fifo_status;
+	struct sirfsoc_int_status *uint_st = &sirfport->uart_reg->uart_int_st;
+	struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
 	struct uart_state *state = port->state;
 	struct circ_buf *xmit = &port->state->xmit;
 	spin_lock(&port->lock);
-	intr_status = rd_regl(port, SIRFUART_INT_STATUS);
-	wr_regl(port, SIRFUART_INT_STATUS, intr_status);
-	intr_status &= rd_regl(port, SIRFUART_INT_EN);
-	if (unlikely(intr_status & (SIRFUART_ERR_INT_STAT))) {
-		if (intr_status & SIRFUART_RXD_BREAK) {
+	intr_status = rd_regl(port, ureg->sirfsoc_int_st_reg);
+	wr_regl(port, ureg->sirfsoc_int_st_reg, intr_status);
+	intr_status &= rd_regl(port, ureg->sirfsoc_int_en_reg);
+	if (unlikely(intr_status & (SIRFUART_ERR_INT_STAT(port, uint_st)))) {
+		if (intr_status & uint_st->sirfsoc_rxd_brk) {
+			port->icount.brk++;
 			if (uart_handle_break(port))
 				goto recv_char;
-			uart_insert_char(port, intr_status,
-					SIRFUART_RX_OFLOW, 0, TTY_BREAK);
-			spin_unlock(&port->lock);
-			return IRQ_HANDLED;
 		}
-		if (intr_status & SIRFUART_RX_OFLOW)
+		if (intr_status & uint_st->sirfsoc_rx_oflow)
 			port->icount.overrun++;
-		if (intr_status & SIRFUART_FRM_ERR) {
+		if (intr_status & uint_st->sirfsoc_frm_err) {
 			port->icount.frame++;
 			flag = TTY_FRAME;
 		}
-		if (intr_status & SIRFUART_PARITY_ERR)
+		if (intr_status & uint_st->sirfsoc_parity_err)
 			flag = TTY_PARITY;
-		wr_regl(port, SIRFUART_RX_FIFO_OP, SIRFUART_RX_FIFO_RESET);
-		wr_regl(port, SIRFUART_RX_FIFO_OP, 0);
-		wr_regl(port, SIRFUART_RX_FIFO_OP, SIRFUART_RX_FIFO_START);
+		wr_regl(port, ureg->sirfsoc_rx_fifo_op, SIRFUART_FIFO_RESET);
+		wr_regl(port, ureg->sirfsoc_rx_fifo_op, 0);
+		wr_regl(port, ureg->sirfsoc_rx_fifo_op, SIRFUART_FIFO_START);
 		intr_status &= port->read_status_mask;
 		uart_insert_char(port, intr_status,
-					SIRFUART_RX_OFLOW_INT, 0, flag);
+					uint_en->sirfsoc_rx_oflow_en, 0, flag);
+		tty_flip_buffer_push(&state->port);
 	}
 recv_char:
-	if (intr_status & SIRFUART_CTS_INT_EN) {
-		cts_status = !(rd_regl(port, SIRFUART_AFC_CTRL) &
-							SIRFUART_CTS_IN_STATUS);
-		if (cts_status != 0) {
-			uart_handle_cts_change(port, 1);
-		} else {
-			uart_handle_cts_change(port, 0);
-			wake_up_interruptible(&state->port.delta_msr_wait);
-		}
+	if ((sirfport->uart_reg->uart_type == SIRF_REAL_UART) &&
+			(intr_status & SIRFUART_CTS_INT_ST(uint_st)) &&
+			!sirfport->tx_dma_state) {
+		cts_status = rd_regl(port, ureg->sirfsoc_afc_ctrl) &
+					SIRFUART_AFC_CTS_STATUS;
+		if (cts_status != 0)
+			cts_status = 0;
+		else
+			cts_status = 1;
+		uart_handle_cts_change(port, cts_status);
+		wake_up_interruptible(&state->port.delta_msr_wait);
 	}
-	if (intr_status & SIRFUART_RX_IO_INT_EN)
-		sirfsoc_uart_pio_rx_chars(port, SIRFSOC_UART_IO_RX_MAX_CNT);
-	if (intr_status & SIRFUART_TX_INT_EN) {
-		if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
-			spin_unlock(&port->lock);
-			return IRQ_HANDLED;
-		} else {
-			sirfsoc_uart_pio_tx_chars(sirfport,
+	if (IS_DMA_CHAN_VALID(sirfport->rx_dma_no)) {
+		if (intr_status & uint_st->sirfsoc_rx_timeout)
+			sirfsoc_uart_handle_rx_tmo(sirfport);
+		if (intr_status & uint_st->sirfsoc_rx_done)
+			sirfsoc_uart_handle_rx_done(sirfport);
+	} else {
+		if (intr_status & SIRFUART_RX_IO_INT_ST(uint_st))
+			sirfsoc_uart_pio_rx_chars(port,
+					SIRFSOC_UART_IO_RX_MAX_CNT);
+	}
+	if (intr_status & uint_st->sirfsoc_txfifo_empty) {
+		if (IS_DMA_CHAN_VALID(sirfport->tx_dma_no))
+			sirfsoc_uart_tx_with_dma(sirfport);
+		else {
+			if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
+				spin_unlock(&port->lock);
+				return IRQ_HANDLED;
+			} else {
+				sirfsoc_uart_pio_tx_chars(sirfport,
 					SIRFSOC_UART_IO_TX_REASONABLE_CNT);
-			if ((uart_circ_empty(xmit)) &&
-				(rd_regl(port, SIRFUART_TX_FIFO_STATUS) &
-						SIRFUART_FIFOEMPTY_MASK(port)))
-				sirfsoc_uart_stop_tx(port);
+				if ((uart_circ_empty(xmit)) &&
+				(rd_regl(port, ureg->sirfsoc_tx_fifo_status) &
+				ufifo_st->ff_empty(port->line)))
+					sirfsoc_uart_stop_tx(port);
+			}
 		}
 	}
 	spin_unlock(&port->lock);
 	return IRQ_HANDLED;
 }
 
+static void sirfsoc_uart_rx_dma_complete_tl(unsigned long param)
+{
+	struct sirfsoc_uart_port *sirfport = (struct sirfsoc_uart_port *)param;
+	struct uart_port *port = &sirfport->port;
+	unsigned long flags;
+	spin_lock_irqsave(&sirfport->rx_lock, flags);
+	while (sirfport->rx_completed != sirfport->rx_issued) {
+		sirfsoc_uart_insert_rx_buf_to_tty(sirfport,
+					SIRFSOC_RX_DMA_BUF_SIZE);
+		sirfsoc_rx_submit_one_dma_desc(port, sirfport->rx_completed++);
+		sirfport->rx_completed %= SIRFSOC_RX_LOOP_BUF_CNT;
+	}
+	spin_unlock_irqrestore(&sirfport->rx_lock, flags);
+}
+
+static void sirfsoc_uart_rx_dma_complete_callback(void *param)
+{
+	struct sirfsoc_uart_port *sirfport = (struct sirfsoc_uart_port *)param;
+	spin_lock(&sirfport->rx_lock);
+	sirfport->rx_issued++;
+	sirfport->rx_issued %= SIRFSOC_RX_LOOP_BUF_CNT;
+	spin_unlock(&sirfport->rx_lock);
+	tasklet_schedule(&sirfport->rx_dma_complete_tasklet);
+}
+
+/* submit rx dma task into dmaengine */
+static void sirfsoc_uart_start_next_rx_dma(struct uart_port *port)
+{
+	struct sirfsoc_uart_port *sirfport = to_sirfport(port);
+	struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
+	struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
+	unsigned long flags;
+	int i;
+	spin_lock_irqsave(&sirfport->rx_lock, flags);
+	sirfport->rx_io_count = 0;
+	wr_regl(port, ureg->sirfsoc_rx_dma_io_ctrl,
+		rd_regl(port, ureg->sirfsoc_rx_dma_io_ctrl) &
+		~SIRFUART_IO_MODE);
+	spin_unlock_irqrestore(&sirfport->rx_lock, flags);
+	for (i = 0; i < SIRFSOC_RX_LOOP_BUF_CNT; i++)
+		sirfsoc_rx_submit_one_dma_desc(port, i);
+	sirfport->rx_completed = sirfport->rx_issued = 0;
+	spin_lock_irqsave(&sirfport->rx_lock, flags);
+	if (!sirfport->is_marco)
+		wr_regl(port, ureg->sirfsoc_int_en_reg,
+				rd_regl(port, ureg->sirfsoc_int_en_reg) |
+				SIRFUART_RX_DMA_INT_EN(port, uint_en));
+	else
+		wr_regl(port, ureg->sirfsoc_int_en_reg,
+			SIRFUART_RX_DMA_INT_EN(port, uint_en));
+	spin_unlock_irqrestore(&sirfport->rx_lock, flags);
+}
+
 static void sirfsoc_uart_start_rx(struct uart_port *port)
 {
-	unsigned long regv;
-	regv = rd_regl(port, SIRFUART_INT_EN);
-	wr_regl(port, SIRFUART_INT_EN, regv | SIRFUART_RX_IO_INT_EN);
-	wr_regl(port, SIRFUART_RX_FIFO_OP, SIRFUART_RX_FIFO_RESET);
-	wr_regl(port, SIRFUART_RX_FIFO_OP, 0);
-	wr_regl(port, SIRFUART_RX_FIFO_OP, SIRFUART_RX_FIFO_START);
+	struct sirfsoc_uart_port *sirfport = to_sirfport(port);
+	struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
+	struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
+
+	sirfport->rx_io_count = 0;
+	wr_regl(port, ureg->sirfsoc_rx_fifo_op, SIRFUART_FIFO_RESET);
+	wr_regl(port, ureg->sirfsoc_rx_fifo_op, 0);
+	wr_regl(port, ureg->sirfsoc_rx_fifo_op, SIRFUART_FIFO_START);
+	if (IS_DMA_CHAN_VALID(sirfport->rx_dma_no))
+		sirfsoc_uart_start_next_rx_dma(port);
+	else {
+		if (!sirfport->is_marco)
+			wr_regl(port, ureg->sirfsoc_int_en_reg,
+				rd_regl(port, ureg->sirfsoc_int_en_reg) |
+				SIRFUART_RX_IO_INT_EN(port, uint_en));
+		else
+			wr_regl(port, ureg->sirfsoc_int_en_reg,
+				SIRFUART_RX_IO_INT_EN(port, uint_en));
+	}
+}
+
+static unsigned int
+sirfsoc_usp_calc_sample_div(unsigned long set_rate,
+		unsigned long ioclk_rate, unsigned long *sample_reg)
+{
+	unsigned long min_delta = ~0UL;
+	unsigned short sample_div;
+	unsigned long ioclk_div = 0;
+	unsigned long temp_delta;
+
+	for (sample_div = SIRF_MIN_SAMPLE_DIV;
+			sample_div <= SIRF_MAX_SAMPLE_DIV; sample_div++) {
+		temp_delta = ioclk_rate -
+		(ioclk_rate + (set_rate * sample_div) / 2)
+		/ (set_rate * sample_div) * set_rate * sample_div;
+
+		temp_delta = (temp_delta > 0) ? temp_delta : -temp_delta;
+		if (temp_delta < min_delta) {
+			ioclk_div = (2 * ioclk_rate /
+				(set_rate * sample_div) + 1) / 2 - 1;
+			if (ioclk_div > SIRF_IOCLK_DIV_MAX)
+				continue;
+			min_delta = temp_delta;
+			*sample_reg = sample_div;
+			if (!temp_delta)
+				break;
+		}
+	}
+	return ioclk_div;
 }
 
 static unsigned int
-sirfsoc_calc_sample_div(unsigned long baud_rate,
-			unsigned long ioclk_rate, unsigned long *setted_baud)
+sirfsoc_uart_calc_sample_div(unsigned long baud_rate,
+			unsigned long ioclk_rate, unsigned long *set_baud)
 {
 	unsigned long min_delta = ~0UL;
 	unsigned short sample_div;
@@ -346,7 +833,7 @@ sirfsoc_calc_sample_div(unsigned long baud_rate,
 			regv = regv & (~SIRF_SAMPLE_DIV_MASK);
 			regv = regv | (sample_div << SIRF_SAMPLE_DIV_SHIFT);
 			min_delta = temp_delta;
-			*setted_baud = baud_tmp;
+			*set_baud = baud_tmp;
 		}
 	}
 	return regv;
@@ -357,63 +844,93 @@ static void sirfsoc_uart_set_termios(struct uart_port *port,
 				       struct ktermios *old)
 {
 	struct sirfsoc_uart_port *sirfport = to_sirfport(port);
+	struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
+	struct sirfsoc_int_en *uint_en = &sirfport->uart_reg->uart_int_en;
 	unsigned long	config_reg = 0;
 	unsigned long	baud_rate;
-	unsigned long	setted_baud;
+	unsigned long	set_baud;
 	unsigned long	flags;
 	unsigned long	ic;
 	unsigned int	clk_div_reg = 0;
-	unsigned long	temp_reg_val;
+	unsigned long	txfifo_op_reg, ioclk_rate;
 	unsigned long	rx_time_out;
 	int		threshold_div;
-	int		temp;
+	u32		data_bit_len, stop_bit_len, len_val;
+	unsigned long	sample_div_reg = 0xf;
+	ioclk_rate	= port->uartclk;
 
 	switch (termios->c_cflag & CSIZE) {
 	default:
 	case CS8:
+		data_bit_len = 8;
 		config_reg |= SIRFUART_DATA_BIT_LEN_8;
 		break;
 	case CS7:
+		data_bit_len = 7;
 		config_reg |= SIRFUART_DATA_BIT_LEN_7;
 		break;
 	case CS6:
+		data_bit_len = 6;
 		config_reg |= SIRFUART_DATA_BIT_LEN_6;
 		break;
 	case CS5:
+		data_bit_len = 5;
 		config_reg |= SIRFUART_DATA_BIT_LEN_5;
 		break;
 	}
-	if (termios->c_cflag & CSTOPB)
+	if (termios->c_cflag & CSTOPB) {
 		config_reg |= SIRFUART_STOP_BIT_LEN_2;
-	baud_rate = uart_get_baud_rate(port, termios, old, 0, 4000000);
+		stop_bit_len = 2;
+	} else
+		stop_bit_len = 1;
+
 	spin_lock_irqsave(&port->lock, flags);
-	port->read_status_mask = SIRFUART_RX_OFLOW_INT;
+	port->read_status_mask = uint_en->sirfsoc_rx_oflow_en;
 	port->ignore_status_mask = 0;
-	/* read flags */
-	if (termios->c_iflag & INPCK)
-		port->read_status_mask |=
-			SIRFUART_FRM_ERR_INT | SIRFUART_PARITY_ERR_INT;
+	if (sirfport->uart_reg->uart_type == SIRF_REAL_UART) {
+		if (termios->c_iflag & INPCK)
+			port->read_status_mask |= uint_en->sirfsoc_frm_err_en |
+				uint_en->sirfsoc_parity_err_en;
+	} else {
+		if (termios->c_iflag & INPCK)
+			port->read_status_mask |= uint_en->sirfsoc_frm_err_en;
+	}
 	if (termios->c_iflag & (BRKINT | PARMRK))
-		port->read_status_mask |= SIRFUART_RXD_BREAK_INT;
-	/* ignore flags */
-	if (termios->c_iflag & IGNPAR)
+			port->read_status_mask |= uint_en->sirfsoc_rxd_brk_en;
+	if (sirfport->uart_reg->uart_type == SIRF_REAL_UART) {
+		if (termios->c_iflag & IGNPAR)
+			port->ignore_status_mask |=
+				uint_en->sirfsoc_frm_err_en |
+				uint_en->sirfsoc_parity_err_en;
+		if (termios->c_cflag & PARENB) {
+			if (termios->c_cflag & CMSPAR) {
+				if (termios->c_cflag & PARODD)
+					config_reg |= SIRFUART_STICK_BIT_MARK;
+				else
+					config_reg |= SIRFUART_STICK_BIT_SPACE;
+			} else if (termios->c_cflag & PARODD) {
+				config_reg |= SIRFUART_STICK_BIT_ODD;
+			} else {
+				config_reg |= SIRFUART_STICK_BIT_EVEN;
+			}
+		}
+	} else {
+		if (termios->c_iflag & IGNPAR)
+			port->ignore_status_mask |=
+				uint_en->sirfsoc_frm_err_en;
+		if (termios->c_cflag & PARENB)
+			dev_warn(port->dev,
+					"USP-UART not support parity err\n");
+	}
+	if (termios->c_iflag & IGNBRK) {
 		port->ignore_status_mask |=
-			SIRFUART_FRM_ERR_INT | SIRFUART_PARITY_ERR_INT;
+			uint_en->sirfsoc_rxd_brk_en;
+		if (termios->c_iflag & IGNPAR)
+			port->ignore_status_mask |=
+				uint_en->sirfsoc_rx_oflow_en;
+	}
 	if ((termios->c_cflag & CREAD) == 0)
 		port->ignore_status_mask |= SIRFUART_DUMMY_READ;
-	/* enable parity if PARENB is set*/
-	if (termios->c_cflag & PARENB) {
-		if (termios->c_cflag & CMSPAR) {
-			if (termios->c_cflag & PARODD)
-				config_reg |= SIRFUART_STICK_BIT_MARK;
-			else
-				config_reg |= SIRFUART_STICK_BIT_SPACE;
-		} else if (termios->c_cflag & PARODD) {
-			config_reg |= SIRFUART_STICK_BIT_ODD;
-		} else {
-			config_reg |= SIRFUART_STICK_BIT_EVEN;
-		}
-	}
 	/* Hardware Flow Control Settings */
 	if (UART_ENABLE_MS(port, termios->c_cflag)) {
 		if (!sirfport->ms_enabled)
@@ -422,75 +939,184 @@ static void sirfsoc_uart_set_termios(struct uart_port *port,
 		if (sirfport->ms_enabled)
 			sirfsoc_uart_disable_ms(port);
 	}
-
-	if (port->uartclk == 150000000) {
-		/* common rate: fast calculation */
+	baud_rate = uart_get_baud_rate(port, termios, old, 0, 4000000);
+	if (ioclk_rate == 150000000) {
 		for (ic = 0; ic < SIRF_BAUD_RATE_SUPPORT_NR; ic++)
 			if (baud_rate == baudrate_to_regv[ic].baud_rate)
 				clk_div_reg = baudrate_to_regv[ic].reg_val;
 	}
-
-	setted_baud = baud_rate;
-	/* arbitary rate setting */
-	if (unlikely(clk_div_reg == 0))
-		clk_div_reg = sirfsoc_calc_sample_div(baud_rate, port->uartclk,
-								&setted_baud);
-	wr_regl(port, SIRFUART_DIVISOR, clk_div_reg);
-
+	set_baud = baud_rate;
+	if (sirfport->uart_reg->uart_type == SIRF_REAL_UART) {
+		if (unlikely(clk_div_reg == 0))
+			clk_div_reg = sirfsoc_uart_calc_sample_div(baud_rate,
+					ioclk_rate, &set_baud);
+		wr_regl(port, ureg->sirfsoc_divisor, clk_div_reg);
+	} else {
+		clk_div_reg = sirfsoc_usp_calc_sample_div(baud_rate,
+				ioclk_rate, &sample_div_reg);
+		sample_div_reg--;
+		set_baud = ((ioclk_rate / (clk_div_reg+1) - 1) /
+				(sample_div_reg + 1));
+		/* setting usp mode 2 */
+		len_val = ((1 << SIRFSOC_USP_MODE2_RXD_DELAY_OFFSET) |
+				(1 << SIRFSOC_USP_MODE2_TXD_DELAY_OFFSET));
+		len_val |= ((clk_div_reg & SIRFSOC_USP_MODE2_CLK_DIVISOR_MASK)
+				<< SIRFSOC_USP_MODE2_CLK_DIVISOR_OFFSET);
+		wr_regl(port, ureg->sirfsoc_mode2, len_val);
+	}
 	if (tty_termios_baud_rate(termios))
-		tty_termios_encode_baud_rate(termios, setted_baud, setted_baud);
-
-	/* set receive timeout */
-	rx_time_out = SIRFSOC_UART_RX_TIMEOUT(baud_rate, 20000);
-	rx_time_out = (rx_time_out > 0xFFFF) ? 0xFFFF : rx_time_out;
-	config_reg |= SIRFUART_RECV_TIMEOUT(rx_time_out);
-	temp_reg_val = rd_regl(port, SIRFUART_TX_FIFO_OP);
-	wr_regl(port, SIRFUART_RX_FIFO_OP, 0);
-	wr_regl(port, SIRFUART_TX_FIFO_OP,
-				temp_reg_val & ~SIRFUART_TX_FIFO_START);
-	wr_regl(port, SIRFUART_TX_DMA_IO_CTRL, SIRFUART_TX_MODE_IO);
-	wr_regl(port, SIRFUART_RX_DMA_IO_CTRL, SIRFUART_RX_MODE_IO);
-	wr_regl(port, SIRFUART_LINE_CTRL, config_reg);
-
+		tty_termios_encode_baud_rate(termios, set_baud, set_baud);
+	/* set receive timeout && data bits len */
+	rx_time_out = SIRFSOC_UART_RX_TIMEOUT(set_baud, 20000);
+	rx_time_out = SIRFUART_RECV_TIMEOUT_VALUE(rx_time_out);
+	txfifo_op_reg = rd_regl(port, ureg->sirfsoc_tx_fifo_op);
+	wr_regl(port, ureg->sirfsoc_rx_fifo_op, SIRFUART_FIFO_STOP);
+	wr_regl(port, ureg->sirfsoc_tx_fifo_op,
+			(txfifo_op_reg & ~SIRFUART_FIFO_START));
+	if (sirfport->uart_reg->uart_type == SIRF_REAL_UART) {
+		config_reg |= SIRFUART_RECV_TIMEOUT(port, rx_time_out);
+		wr_regl(port, ureg->sirfsoc_line_ctrl, config_reg);
+	} else {
+		/*tx frame ctrl*/
+		len_val = (data_bit_len - 1) << SIRFSOC_USP_TX_DATA_LEN_OFFSET;
+		len_val |= (data_bit_len + 1 + stop_bit_len - 1) <<
+				SIRFSOC_USP_TX_FRAME_LEN_OFFSET;
+		len_val |= ((data_bit_len - 1) <<
+				SIRFSOC_USP_TX_SHIFTER_LEN_OFFSET);
+		len_val |= (((clk_div_reg & 0xc00) >> 10) <<
+				SIRFSOC_USP_TX_CLK_DIVISOR_OFFSET);
+		wr_regl(port, ureg->sirfsoc_tx_frame_ctrl, len_val);
+		/*rx frame ctrl*/
+		len_val = (data_bit_len - 1) << SIRFSOC_USP_RX_DATA_LEN_OFFSET;
+		len_val |= (data_bit_len + 1 + stop_bit_len - 1) <<
+				SIRFSOC_USP_RX_FRAME_LEN_OFFSET;
+		len_val |= (data_bit_len - 1) <<
+				SIRFSOC_USP_RX_SHIFTER_LEN_OFFSET;
+		len_val |= (((clk_div_reg & 0xf000) >> 12) <<
+				SIRFSOC_USP_RX_CLK_DIVISOR_OFFSET);
+		wr_regl(port, ureg->sirfsoc_rx_frame_ctrl, len_val);
+		/*async param*/
+		wr_regl(port, ureg->sirfsoc_async_param_reg,
+			(SIRFUART_RECV_TIMEOUT(port, rx_time_out)) |
+			(sample_div_reg & SIRFSOC_USP_ASYNC_DIV2_MASK) <<
+			SIRFSOC_USP_ASYNC_DIV2_OFFSET);
+	}
+	if (IS_DMA_CHAN_VALID(sirfport->tx_dma_no))
+		wr_regl(port, ureg->sirfsoc_tx_dma_io_ctrl, SIRFUART_DMA_MODE);
+	else
+		wr_regl(port, ureg->sirfsoc_tx_dma_io_ctrl, SIRFUART_IO_MODE);
+	if (IS_DMA_CHAN_VALID(sirfport->rx_dma_no))
+		wr_regl(port, ureg->sirfsoc_rx_dma_io_ctrl, SIRFUART_DMA_MODE);
+	else
+		wr_regl(port, ureg->sirfsoc_rx_dma_io_ctrl, SIRFUART_IO_MODE);
 	/* Reset Rx/Tx FIFO Threshold level for proper baudrate */
-	if (baud_rate < 1000000)
+	if (set_baud < 1000000)
 		threshold_div = 1;
 	else
 		threshold_div = 2;
-	temp = port->line == 1 ? 16 : 64;
-	wr_regl(port, SIRFUART_TX_FIFO_CTRL, temp / threshold_div);
-	wr_regl(port, SIRFUART_RX_FIFO_CTRL, temp / threshold_div);
-	temp_reg_val |= SIRFUART_TX_FIFO_START;
-	wr_regl(port, SIRFUART_TX_FIFO_OP, temp_reg_val);
-	uart_update_timeout(port, termios->c_cflag, baud_rate);
+	wr_regl(port, ureg->sirfsoc_tx_fifo_ctrl,
+				SIRFUART_FIFO_THD(port) / threshold_div);
+	wr_regl(port, ureg->sirfsoc_rx_fifo_ctrl,
+				SIRFUART_FIFO_THD(port) / threshold_div);
+	txfifo_op_reg |= SIRFUART_FIFO_START;
+	wr_regl(port, ureg->sirfsoc_tx_fifo_op, txfifo_op_reg);
+	uart_update_timeout(port, termios->c_cflag, set_baud);
 	sirfsoc_uart_start_rx(port);
-	wr_regl(port, SIRFUART_TX_RX_EN, SIRFUART_TX_EN | SIRFUART_RX_EN);
+	wr_regl(port, ureg->sirfsoc_tx_rx_en, SIRFUART_TX_EN | SIRFUART_RX_EN);
 	spin_unlock_irqrestore(&port->lock, flags);
 }
 
-static void startup_uart_controller(struct uart_port *port)
+static unsigned int sirfsoc_uart_init_tx_dma(struct uart_port *port)
 {
-	unsigned long temp_regv;
-	int temp;
-	temp_regv = rd_regl(port, SIRFUART_TX_DMA_IO_CTRL);
-	wr_regl(port, SIRFUART_TX_DMA_IO_CTRL, temp_regv | SIRFUART_TX_MODE_IO);
-	temp_regv = rd_regl(port, SIRFUART_RX_DMA_IO_CTRL);
-	wr_regl(port, SIRFUART_RX_DMA_IO_CTRL, temp_regv | SIRFUART_RX_MODE_IO);
-	wr_regl(port, SIRFUART_TX_DMA_IO_LEN, 0);
-	wr_regl(port, SIRFUART_RX_DMA_IO_LEN, 0);
-	wr_regl(port, SIRFUART_TX_RX_EN, SIRFUART_RX_EN | SIRFUART_TX_EN);
-	wr_regl(port, SIRFUART_TX_FIFO_OP, SIRFUART_TX_FIFO_RESET);
-	wr_regl(port, SIRFUART_TX_FIFO_OP, 0);
-	wr_regl(port, SIRFUART_RX_FIFO_OP, SIRFUART_RX_FIFO_RESET);
-	wr_regl(port, SIRFUART_RX_FIFO_OP, 0);
-	temp = port->line == 1 ? 16 : 64;
-	wr_regl(port, SIRFUART_TX_FIFO_CTRL, temp);
-	wr_regl(port, SIRFUART_RX_FIFO_CTRL, temp);
+	struct sirfsoc_uart_port *sirfport = to_sirfport(port);
+	dma_cap_mask_t dma_mask;
+	struct dma_slave_config tx_slv_cfg = {
+		.dst_maxburst = 2,
+	};
+
+	dma_cap_zero(dma_mask);
+	dma_cap_set(DMA_SLAVE, dma_mask);
+	sirfport->tx_dma_chan = dma_request_channel(dma_mask,
+		(dma_filter_fn)sirfsoc_dma_filter_id,
+		(void *)sirfport->tx_dma_no);
+	if (!sirfport->tx_dma_chan) {
+		dev_err(port->dev, "Uart Request Dma Channel Fail %d\n",
+					sirfport->tx_dma_no);
+		return  -EPROBE_DEFER;
+	}
+	dmaengine_slave_config(sirfport->tx_dma_chan, &tx_slv_cfg);
+
+	return 0;
+}
+
+static unsigned int sirfsoc_uart_init_rx_dma(struct uart_port *port)
+{
+	struct sirfsoc_uart_port *sirfport = to_sirfport(port);
+	dma_cap_mask_t dma_mask;
+	int ret;
+	int i, j;
+	struct dma_slave_config slv_cfg = {
+		.src_maxburst = 2,
+	};
+
+	dma_cap_zero(dma_mask);
+	dma_cap_set(DMA_SLAVE, dma_mask);
+	sirfport->rx_dma_chan = dma_request_channel(dma_mask,
+					(dma_filter_fn)sirfsoc_dma_filter_id,
+					(void *)sirfport->rx_dma_no);
+	if (!sirfport->rx_dma_chan) {
+		dev_err(port->dev, "Uart Request Dma Channel Fail %d\n",
+				sirfport->rx_dma_no);
+		ret = -EPROBE_DEFER;
+		goto request_err;
+	}
+	for (i = 0; i < SIRFSOC_RX_LOOP_BUF_CNT; i++) {
+		sirfport->rx_dma_items[i].xmit.buf =
+			dma_alloc_coherent(port->dev, SIRFSOC_RX_DMA_BUF_SIZE,
+			&sirfport->rx_dma_items[i].dma_addr, GFP_KERNEL);
+		if (!sirfport->rx_dma_items[i].xmit.buf) {
+			dev_err(port->dev, "Uart alloc bufa failed\n");
+			ret = -ENOMEM;
+			goto alloc_coherent_err;
+		}
+		sirfport->rx_dma_items[i].xmit.head =
+			sirfport->rx_dma_items[i].xmit.tail = 0;
+	}
+	dmaengine_slave_config(sirfport->rx_dma_chan, &slv_cfg);
+
+	return 0;
+alloc_coherent_err:
+	for (j = 0; j < i; j++)
+		dma_free_coherent(port->dev, SIRFSOC_RX_DMA_BUF_SIZE,
+				sirfport->rx_dma_items[j].xmit.buf,
+				sirfport->rx_dma_items[j].dma_addr);
+	dma_release_channel(sirfport->rx_dma_chan);
+request_err:
+	return ret;
+}
+
+static void sirfsoc_uart_uninit_tx_dma(struct sirfsoc_uart_port *sirfport)
+{
+	dmaengine_terminate_all(sirfport->tx_dma_chan);
+	dma_release_channel(sirfport->tx_dma_chan);
+}
+
+static void sirfsoc_uart_uninit_rx_dma(struct sirfsoc_uart_port *sirfport)
+{
+	int i;
+	struct uart_port *port = &sirfport->port;
+	dmaengine_terminate_all(sirfport->rx_dma_chan);
+	dma_release_channel(sirfport->rx_dma_chan);
+	for (i = 0; i < SIRFSOC_RX_LOOP_BUF_CNT; i++)
+		dma_free_coherent(port->dev, SIRFSOC_RX_DMA_BUF_SIZE,
+				sirfport->rx_dma_items[i].xmit.buf,
+				sirfport->rx_dma_items[i].dma_addr);
 }
 
 static int sirfsoc_uart_startup(struct uart_port *port)
 {
 	struct sirfsoc_uart_port *sirfport	= to_sirfport(port);
+	struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
 	unsigned int index			= port->line;
 	int ret;
 	set_irq_flags(port->irq, IRQF_VALID | IRQF_NOAUTOEN);
@@ -504,8 +1130,64 @@ static int sirfsoc_uart_startup(struct uart_port *port)
 							index, port->irq);
 		goto irq_err;
 	}
-	startup_uart_controller(port);
+
+	/* initial hardware settings */
+	wr_regl(port, ureg->sirfsoc_tx_dma_io_ctrl,
+		rd_regl(port, ureg->sirfsoc_tx_dma_io_ctrl) |
+		SIRFUART_IO_MODE);
+	wr_regl(port, ureg->sirfsoc_rx_dma_io_ctrl,
+		rd_regl(port, ureg->sirfsoc_rx_dma_io_ctrl) |
+		SIRFUART_IO_MODE);
+	wr_regl(port, ureg->sirfsoc_tx_dma_io_len, 0);
+	wr_regl(port, ureg->sirfsoc_rx_dma_io_len, 0);
+	wr_regl(port, ureg->sirfsoc_tx_rx_en, SIRFUART_RX_EN | SIRFUART_TX_EN);
+	if (sirfport->uart_reg->uart_type == SIRF_USP_UART)
+		wr_regl(port, ureg->sirfsoc_mode1,
+			SIRFSOC_USP_ENDIAN_CTRL_LSBF |
+			SIRFSOC_USP_EN);
+	wr_regl(port, ureg->sirfsoc_tx_fifo_op, SIRFUART_FIFO_RESET);
+	wr_regl(port, ureg->sirfsoc_tx_fifo_op, 0);
+	wr_regl(port, ureg->sirfsoc_rx_fifo_op, SIRFUART_FIFO_RESET);
+	wr_regl(port, ureg->sirfsoc_rx_fifo_op, 0);
+	wr_regl(port, ureg->sirfsoc_tx_fifo_ctrl, SIRFUART_FIFO_THD(port));
+	wr_regl(port, ureg->sirfsoc_rx_fifo_ctrl, SIRFUART_FIFO_THD(port));
+
+	if (IS_DMA_CHAN_VALID(sirfport->rx_dma_no)) {
+		ret = sirfsoc_uart_init_rx_dma(port);
+		if (ret)
+			goto init_rx_err;
+		wr_regl(port, ureg->sirfsoc_rx_fifo_level_chk,
+				SIRFUART_RX_FIFO_CHK_SC(port->line, 0x4) |
+				SIRFUART_RX_FIFO_CHK_LC(port->line, 0xe) |
+				SIRFUART_RX_FIFO_CHK_HC(port->line, 0x1b));
+	}
+	if (IS_DMA_CHAN_VALID(sirfport->tx_dma_no)) {
+		sirfsoc_uart_init_tx_dma(port);
+		sirfport->tx_dma_state = TX_DMA_IDLE;
+		wr_regl(port, ureg->sirfsoc_tx_fifo_level_chk,
+				SIRFUART_TX_FIFO_CHK_SC(port->line, 0x1b) |
+				SIRFUART_TX_FIFO_CHK_LC(port->line, 0xe) |
+				SIRFUART_TX_FIFO_CHK_HC(port->line, 0x4));
+	}
+	sirfport->ms_enabled = false;
+	if (sirfport->uart_reg->uart_type == SIRF_USP_UART &&
+		sirfport->hw_flow_ctrl) {
+		set_irq_flags(gpio_to_irq(sirfport->cts_gpio),
+			IRQF_VALID | IRQF_NOAUTOEN);
+		ret = request_irq(gpio_to_irq(sirfport->cts_gpio),
+			sirfsoc_uart_usp_cts_handler, IRQF_TRIGGER_FALLING |
+			IRQF_TRIGGER_RISING, "usp_cts_irq", sirfport);
+		if (ret != 0) {
+			dev_err(port->dev, "UART-USP:request gpio irq fail\n");
+			goto init_rx_err;
+		}
+	}
+
 	enable_irq(port->irq);
+
+	return 0;
+init_rx_err:
+	free_irq(port->irq, sirfport);
 irq_err:
 	return ret;
 }
@@ -513,11 +1195,25 @@ irq_err:
 static void sirfsoc_uart_shutdown(struct uart_port *port)
 {
 	struct sirfsoc_uart_port *sirfport = to_sirfport(port);
-	wr_regl(port, SIRFUART_INT_EN, 0);
+	struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
+	if (!sirfport->is_marco)
+		wr_regl(port, ureg->sirfsoc_int_en_reg, 0);
+	else
+		wr_regl(port, SIRFUART_INT_EN_CLR, ~0UL);
+
 	free_irq(port->irq, sirfport);
-	if (sirfport->ms_enabled) {
+	if (sirfport->ms_enabled)
 		sirfsoc_uart_disable_ms(port);
-		sirfport->ms_enabled = 0;
+	if (sirfport->uart_reg->uart_type == SIRF_USP_UART &&
+			sirfport->hw_flow_ctrl) {
+		gpio_set_value(sirfport->rts_gpio, 1);
+		free_irq(gpio_to_irq(sirfport->cts_gpio), sirfport);
+	}
+	if (IS_DMA_CHAN_VALID(sirfport->rx_dma_no))
+		sirfsoc_uart_uninit_rx_dma(sirfport);
+	if (IS_DMA_CHAN_VALID(sirfport->tx_dma_no)) {
+		sirfsoc_uart_uninit_tx_dma(sirfport);
+		sirfport->tx_dma_state = TX_DMA_IDLE;
 	}
 }
 
@@ -528,9 +1224,11 @@ static const char *sirfsoc_uart_type(struct uart_port *port)
 
 static int sirfsoc_uart_request_port(struct uart_port *port)
 {
+	struct sirfsoc_uart_port *sirfport = to_sirfport(port);
+	struct sirfsoc_uart_param *uart_param = &sirfport->uart_reg->uart_param;
 	void *ret;
 	ret = request_mem_region(port->mapbase,
-				SIRFUART_MAP_SIZE, SIRFUART_PORT_NAME);
+		SIRFUART_MAP_SIZE, uart_param->port_name);
 	return ret ? 0 : -EBUSY;
 }
 
@@ -566,32 +1264,45 @@ static struct uart_ops sirfsoc_uart_ops = {
 };
 
 #ifdef CONFIG_SERIAL_SIRFSOC_CONSOLE
-static int __init sirfsoc_uart_console_setup(struct console *co, char *options)
+static int __init
+sirfsoc_uart_console_setup(struct console *co, char *options)
 {
 	unsigned int baud = 115200;
 	unsigned int bits = 8;
 	unsigned int parity = 'n';
 	unsigned int flow = 'n';
 	struct uart_port *port = &sirfsoc_uart_ports[co->index].port;
-
+	struct sirfsoc_uart_port *sirfport = to_sirfport(port);
+	struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
 	if (co->index < 0 || co->index >= SIRFSOC_UART_NR)
 		return -EINVAL;
 
 	if (!port->mapbase)
 		return -ENODEV;
 
+	/* enable usp in mode1 register */
+	if (sirfport->uart_reg->uart_type == SIRF_USP_UART)
+		wr_regl(port, ureg->sirfsoc_mode1, SIRFSOC_USP_EN |
+				SIRFSOC_USP_ENDIAN_CTRL_LSBF);
 	if (options)
 		uart_parse_options(options, &baud, &parity, &bits, &flow);
 	port->cons = co;
+
+	/* default console tx/rx transfer using io mode */
+	sirfport->rx_dma_no = UNVALID_DMA_CHAN;
+	sirfport->tx_dma_no = UNVALID_DMA_CHAN;
 	return uart_set_options(port, co, baud, parity, bits, flow);
 }
 
 static void sirfsoc_uart_console_putchar(struct uart_port *port, int ch)
 {
+	struct sirfsoc_uart_port *sirfport = to_sirfport(port);
+	struct sirfsoc_register *ureg = &sirfport->uart_reg->uart_reg;
+	struct sirfsoc_fifo_status *ufifo_st = &sirfport->uart_reg->fifo_status;
 	while (rd_regl(port,
-		SIRFUART_TX_FIFO_STATUS) & SIRFUART_FIFOFULL_MASK(port))
+		ureg->sirfsoc_tx_fifo_status) & ufifo_st->ff_full(port->line))
 		cpu_relax();
-	wr_regb(port, SIRFUART_TX_FIFO_DATA, ch);
+	wr_regb(port, ureg->sirfsoc_tx_fifo_data, ch);
 }
 
 static void sirfsoc_uart_console_write(struct console *co, const char *s,
@@ -633,27 +1344,99 @@ static struct uart_driver sirfsoc_uart_drv = {
 #endif
 };
 
-int sirfsoc_uart_probe(struct platform_device *pdev)
+static struct of_device_id sirfsoc_uart_ids[] = {
+	{ .compatible = "sirf,prima2-uart", .data = &sirfsoc_uart,},
+	{ .compatible = "sirf,marco-uart", .data = &sirfsoc_uart},
+	{ .compatible = "sirf,prima2-usp-uart", .data = &sirfsoc_usp},
+	{}
+};
+MODULE_DEVICE_TABLE(of, sirfsoc_uart_ids);
+
+static int sirfsoc_uart_probe(struct platform_device *pdev)
 {
 	struct sirfsoc_uart_port *sirfport;
 	struct uart_port *port;
 	struct resource *res;
 	int ret;
+	const struct of_device_id *match;
 
+	match = of_match_node(sirfsoc_uart_ids, pdev->dev.of_node);
 	if (of_property_read_u32(pdev->dev.of_node, "cell-index", &pdev->id)) {
 		dev_err(&pdev->dev,
 			"Unable to find cell-index in uart node.\n");
 		ret = -EFAULT;
 		goto err;
 	}
-
+	if (of_device_is_compatible(pdev->dev.of_node, "sirf,prima2-usp-uart"))
+		pdev->id += ((struct sirfsoc_uart_register *)
+				match->data)->uart_param.register_uart_nr;
 	sirfport = &sirfsoc_uart_ports[pdev->id];
 	port = &sirfport->port;
 	port->dev = &pdev->dev;
 	port->private_data = sirfport;
+	sirfport->uart_reg = (struct sirfsoc_uart_register *)match->data;
+
+	sirfport->hw_flow_ctrl = of_property_read_bool(pdev->dev.of_node,
+		"sirf,uart-has-rtscts");
+	if (of_device_is_compatible(pdev->dev.of_node, "sirf,prima2-uart")) {
+		sirfport->uart_reg->uart_type = SIRF_REAL_UART;
+		if (of_property_read_u32(pdev->dev.of_node,
+				"sirf,uart-dma-rx-channel",
+				&sirfport->rx_dma_no))
+			sirfport->rx_dma_no = UNVALID_DMA_CHAN;
+		if (of_property_read_u32(pdev->dev.of_node,
+				"sirf,uart-dma-tx-channel",
+				&sirfport->tx_dma_no))
+			sirfport->tx_dma_no = UNVALID_DMA_CHAN;
+	}
+	if (of_device_is_compatible(pdev->dev.of_node, "sirf,prima2-usp-uart")) {
+		sirfport->uart_reg->uart_type =	SIRF_USP_UART;
+		if (of_property_read_u32(pdev->dev.of_node,
+				"sirf,usp-dma-rx-channel",
+				&sirfport->rx_dma_no))
+			sirfport->rx_dma_no = UNVALID_DMA_CHAN;
+		if (of_property_read_u32(pdev->dev.of_node,
+				"sirf,usp-dma-tx-channel",
+				&sirfport->tx_dma_no))
+			sirfport->tx_dma_no = UNVALID_DMA_CHAN;
+		if (!sirfport->hw_flow_ctrl)
+			goto usp_no_flow_control;
+		if (of_find_property(pdev->dev.of_node, "cts-gpios", NULL))
+			sirfport->cts_gpio = of_get_named_gpio(
+					pdev->dev.of_node, "cts-gpios", 0);
+		else
+			sirfport->cts_gpio = -1;
+		if (of_find_property(pdev->dev.of_node, "rts-gpios", NULL))
+			sirfport->rts_gpio = of_get_named_gpio(
+					pdev->dev.of_node, "rts-gpios", 0);
+		else
+			sirfport->rts_gpio = -1;
 
-	if (of_find_property(pdev->dev.of_node, "hw_flow_ctrl", NULL))
-		sirfport->hw_flow_ctrl = 1;
+		if ((!gpio_is_valid(sirfport->cts_gpio) ||
+			 !gpio_is_valid(sirfport->rts_gpio))) {
+			ret = -EINVAL;
+			dev_err(&pdev->dev,
+				"Usp flow control must have cts and rts gpio");
+			goto err;
+		}
+		ret = devm_gpio_request(&pdev->dev, sirfport->cts_gpio,
+				"usp-cts-gpio");
+		if (ret) {
+			dev_err(&pdev->dev, "Unable request cts gpio");
+			goto err;
+		}
+		gpio_direction_input(sirfport->cts_gpio);
+		ret = devm_gpio_request(&pdev->dev, sirfport->rts_gpio,
+				"usp-rts-gpio");
+		if (ret) {
+			dev_err(&pdev->dev, "Unable request rts gpio");
+			goto err;
+		}
+		gpio_direction_output(sirfport->rts_gpio, 1);
+	}
+usp_no_flow_control:
+	if (of_device_is_compatible(pdev->dev.of_node, "sirf,marco-uart"))
+		sirfport->is_marco = true;
 
 	if (of_property_read_u32(pdev->dev.of_node,
 			"fifosize",
@@ -670,6 +1453,12 @@ int sirfsoc_uart_probe(struct platform_device *pdev)
 		ret = -EFAULT;
 		goto err;
 	}
+	spin_lock_init(&sirfport->rx_lock);
+	spin_lock_init(&sirfport->tx_lock);
+	tasklet_init(&sirfport->rx_dma_complete_tasklet,
+			sirfsoc_uart_rx_dma_complete_tl, (unsigned long)sirfport);
+	tasklet_init(&sirfport->rx_tmo_process_tasklet,
+			sirfsoc_rx_tmo_process_tl, (unsigned long)sirfport);
 	port->mapbase = res->start;
 	port->membase = devm_ioremap(&pdev->dev, res->start, resource_size(res));
 	if (!port->membase) {
@@ -685,18 +1474,10 @@ int sirfsoc_uart_probe(struct platform_device *pdev)
 	}
 	port->irq = res->start;
 
-	if (sirfport->hw_flow_ctrl) {
-		sirfport->p = pinctrl_get_select_default(&pdev->dev);
-		if (IS_ERR(sirfport->p)) {
-			ret = PTR_ERR(sirfport->p);
-			goto err;
-		}
-	}
-
 	sirfport->clk = clk_get(&pdev->dev, NULL);
 	if (IS_ERR(sirfport->clk)) {
 		ret = PTR_ERR(sirfport->clk);
-		goto clk_err;
+		goto err;
 	}
 	clk_prepare_enable(sirfport->clk);
 	port->uartclk = clk_get_rate(sirfport->clk);
@@ -716,10 +1497,6 @@ int sirfsoc_uart_probe(struct platform_device *pdev)
 port_err:
 	clk_disable_unprepare(sirfport->clk);
 	clk_put(sirfport->clk);
-clk_err:
-	platform_set_drvdata(pdev, NULL);
-	if (sirfport->hw_flow_ctrl)
-		pinctrl_put(sirfport->p);
 err:
 	return ret;
 }
@@ -728,9 +1505,6 @@ static int sirfsoc_uart_remove(struct platform_device *pdev)
 {
 	struct sirfsoc_uart_port *sirfport = platform_get_drvdata(pdev);
 	struct uart_port *port = &sirfport->port;
-	platform_set_drvdata(pdev, NULL);
-	if (sirfport->hw_flow_ctrl)
-		pinctrl_put(sirfport->p);
 	clk_disable_unprepare(sirfport->clk);
 	clk_put(sirfport->clk);
 	uart_remove_one_port(&sirfsoc_uart_drv, port);
@@ -754,13 +1528,6 @@ static int sirfsoc_uart_resume(struct platform_device *pdev)
 	return 0;
 }
 
-static struct of_device_id sirfsoc_uart_ids[] = {
-	{ .compatible = "sirf,prima2-uart", },
-	{ .compatible = "sirf,marco-uart", },
-	{}
-};
-MODULE_DEVICE_TABLE(of, sirfsoc_uart_ids);
-
 static struct platform_driver sirfsoc_uart_driver = {
 	.probe		= sirfsoc_uart_probe,
 	.remove		= sirfsoc_uart_remove,
diff --git a/drivers/tty/serial/sirfsoc_uart.h b/drivers/tty/serial/sirfsoc_uart.h
index 85328ba0c4e..fb8d0a00260 100644
--- a/drivers/tty/serial/sirfsoc_uart.h
+++ b/drivers/tty/serial/sirfsoc_uart.h
@@ -6,31 +6,260 @@
  * Licensed under GPLv2 or later.
  */
 #include <linux/bitops.h>
+struct sirfsoc_uart_param {
+	const char *uart_name;
+	const char *port_name;
+	u32 uart_nr;
+	u32 register_uart_nr;
+};
+
+struct sirfsoc_register {
+	/* hardware uart specific */
+	u32 sirfsoc_line_ctrl;
+	u32 sirfsoc_divisor;
+	/* uart - usp common */
+	u32 sirfsoc_tx_rx_en;
+	u32 sirfsoc_int_en_reg;
+	u32 sirfsoc_int_st_reg;
+	u32 sirfsoc_tx_dma_io_ctrl;
+	u32 sirfsoc_tx_dma_io_len;
+	u32 sirfsoc_tx_fifo_ctrl;
+	u32 sirfsoc_tx_fifo_level_chk;
+	u32 sirfsoc_tx_fifo_op;
+	u32 sirfsoc_tx_fifo_status;
+	u32 sirfsoc_tx_fifo_data;
+	u32 sirfsoc_rx_dma_io_ctrl;
+	u32 sirfsoc_rx_dma_io_len;
+	u32 sirfsoc_rx_fifo_ctrl;
+	u32 sirfsoc_rx_fifo_level_chk;
+	u32 sirfsoc_rx_fifo_op;
+	u32 sirfsoc_rx_fifo_status;
+	u32 sirfsoc_rx_fifo_data;
+	u32 sirfsoc_afc_ctrl;
+	u32 sirfsoc_swh_dma_io;
+	/* hardware usp specific */
+	u32 sirfsoc_mode1;
+	u32 sirfsoc_mode2;
+	u32 sirfsoc_tx_frame_ctrl;
+	u32 sirfsoc_rx_frame_ctrl;
+	u32 sirfsoc_async_param_reg;
+};
+
+typedef u32 (*fifo_full_mask)(int line);
+typedef u32 (*fifo_empty_mask)(int line);
+
+struct sirfsoc_fifo_status {
+	fifo_full_mask ff_full;
+	fifo_empty_mask ff_empty;
+};
 
-/* UART Register Offset Define */
-#define SIRFUART_LINE_CTRL			0x0040
-#define SIRFUART_TX_RX_EN			0x004c
-#define SIRFUART_DIVISOR			0x0050
-#define SIRFUART_INT_EN				0x0054
-#define SIRFUART_INT_STATUS			0x0058
-#define SIRFUART_TX_DMA_IO_CTRL			0x0100
-#define SIRFUART_TX_DMA_IO_LEN			0x0104
-#define SIRFUART_TX_FIFO_CTRL			0x0108
-#define SIRFUART_TX_FIFO_LEVEL_CHK		0x010C
-#define SIRFUART_TX_FIFO_OP			0x0110
-#define SIRFUART_TX_FIFO_STATUS			0x0114
-#define SIRFUART_TX_FIFO_DATA			0x0118
-#define SIRFUART_RX_DMA_IO_CTRL			0x0120
-#define SIRFUART_RX_DMA_IO_LEN			0x0124
-#define SIRFUART_RX_FIFO_CTRL			0x0128
-#define SIRFUART_RX_FIFO_LEVEL_CHK		0x012C
-#define SIRFUART_RX_FIFO_OP			0x0130
-#define SIRFUART_RX_FIFO_STATUS			0x0134
-#define SIRFUART_RX_FIFO_DATA			0x0138
-#define SIRFUART_AFC_CTRL			0x0140
-#define SIRFUART_SWH_DMA_IO			0x0148
-
-/* UART Line Control Register */
+struct sirfsoc_int_en {
+	u32 sirfsoc_rx_done_en;
+	u32 sirfsoc_tx_done_en;
+	u32 sirfsoc_rx_oflow_en;
+	u32 sirfsoc_tx_allout_en;
+	u32 sirfsoc_rx_io_dma_en;
+	u32 sirfsoc_tx_io_dma_en;
+	u32 sirfsoc_rxfifo_full_en;
+	u32 sirfsoc_txfifo_empty_en;
+	u32 sirfsoc_rxfifo_thd_en;
+	u32 sirfsoc_txfifo_thd_en;
+	u32 sirfsoc_frm_err_en;
+	u32 sirfsoc_rxd_brk_en;
+	u32 sirfsoc_rx_timeout_en;
+	u32 sirfsoc_parity_err_en;
+	u32 sirfsoc_cts_en;
+	u32 sirfsoc_rts_en;
+};
+
+struct sirfsoc_int_status {
+	u32 sirfsoc_rx_done;
+	u32 sirfsoc_tx_done;
+	u32 sirfsoc_rx_oflow;
+	u32 sirfsoc_tx_allout;
+	u32 sirfsoc_rx_io_dma;
+	u32 sirfsoc_tx_io_dma;
+	u32 sirfsoc_rxfifo_full;
+	u32 sirfsoc_txfifo_empty;
+	u32 sirfsoc_rxfifo_thd;
+	u32 sirfsoc_txfifo_thd;
+	u32 sirfsoc_frm_err;
+	u32 sirfsoc_rxd_brk;
+	u32 sirfsoc_rx_timeout;
+	u32 sirfsoc_parity_err;
+	u32 sirfsoc_cts;
+	u32 sirfsoc_rts;
+};
+
+enum sirfsoc_uart_type {
+	SIRF_REAL_UART,
+	SIRF_USP_UART,
+};
+
+struct sirfsoc_uart_register {
+	struct sirfsoc_register uart_reg;
+	struct sirfsoc_int_en uart_int_en;
+	struct sirfsoc_int_status uart_int_st;
+	struct sirfsoc_fifo_status fifo_status;
+	struct sirfsoc_uart_param uart_param;
+	enum sirfsoc_uart_type uart_type;
+};
+
+u32 usp_ff_full(int line)
+{
+	return 0x80;
+}
+u32 usp_ff_empty(int line)
+{
+	return 0x100;
+}
+u32 uart_ff_full(int line)
+{
+	return (line == 1) ? (0x20) : (0x80);
+}
+u32 uart_ff_empty(int line)
+{
+	return (line == 1) ? (0x40) : (0x100);
+}
+struct sirfsoc_uart_register sirfsoc_usp = {
+	.uart_reg = {
+		.sirfsoc_mode1		= 0x0000,
+		.sirfsoc_mode2		= 0x0004,
+		.sirfsoc_tx_frame_ctrl	= 0x0008,
+		.sirfsoc_rx_frame_ctrl	= 0x000c,
+		.sirfsoc_tx_rx_en	= 0x0010,
+		.sirfsoc_int_en_reg	= 0x0014,
+		.sirfsoc_int_st_reg	= 0x0018,
+		.sirfsoc_async_param_reg = 0x0024,
+		.sirfsoc_tx_dma_io_ctrl	= 0x0100,
+		.sirfsoc_tx_dma_io_len	= 0x0104,
+		.sirfsoc_tx_fifo_ctrl	= 0x0108,
+		.sirfsoc_tx_fifo_level_chk = 0x010c,
+		.sirfsoc_tx_fifo_op	= 0x0110,
+		.sirfsoc_tx_fifo_status	= 0x0114,
+		.sirfsoc_tx_fifo_data	= 0x0118,
+		.sirfsoc_rx_dma_io_ctrl	= 0x0120,
+		.sirfsoc_rx_dma_io_len	= 0x0124,
+		.sirfsoc_rx_fifo_ctrl	= 0x0128,
+		.sirfsoc_rx_fifo_level_chk = 0x012c,
+		.sirfsoc_rx_fifo_op	= 0x0130,
+		.sirfsoc_rx_fifo_status	= 0x0134,
+		.sirfsoc_rx_fifo_data	= 0x0138,
+	},
+	.uart_int_en = {
+		.sirfsoc_rx_done_en	= BIT(0),
+		.sirfsoc_tx_done_en	= BIT(1),
+		.sirfsoc_rx_oflow_en	= BIT(2),
+		.sirfsoc_tx_allout_en	= BIT(3),
+		.sirfsoc_rx_io_dma_en	= BIT(4),
+		.sirfsoc_tx_io_dma_en	= BIT(5),
+		.sirfsoc_rxfifo_full_en	= BIT(6),
+		.sirfsoc_txfifo_empty_en = BIT(7),
+		.sirfsoc_rxfifo_thd_en	= BIT(8),
+		.sirfsoc_txfifo_thd_en	= BIT(9),
+		.sirfsoc_frm_err_en	= BIT(10),
+		.sirfsoc_rx_timeout_en	= BIT(11),
+		.sirfsoc_rxd_brk_en	= BIT(15),
+	},
+	.uart_int_st = {
+		.sirfsoc_rx_done	= BIT(0),
+		.sirfsoc_tx_done	= BIT(1),
+		.sirfsoc_rx_oflow	= BIT(2),
+		.sirfsoc_tx_allout	= BIT(3),
+		.sirfsoc_rx_io_dma	= BIT(4),
+		.sirfsoc_tx_io_dma	= BIT(5),
+		.sirfsoc_rxfifo_full	= BIT(6),
+		.sirfsoc_txfifo_empty	= BIT(7),
+		.sirfsoc_rxfifo_thd	= BIT(8),
+		.sirfsoc_txfifo_thd	= BIT(9),
+		.sirfsoc_frm_err	= BIT(10),
+		.sirfsoc_rx_timeout	= BIT(11),
+		.sirfsoc_rxd_brk	= BIT(15),
+	},
+	.fifo_status = {
+		.ff_full		= usp_ff_full,
+		.ff_empty		= usp_ff_empty,
+	},
+	.uart_param = {
+		.uart_name = "ttySiRF",
+		.port_name = "sirfsoc-uart",
+		.uart_nr = 2,
+		.register_uart_nr = 3,
+	},
+};
+
+struct sirfsoc_uart_register sirfsoc_uart = {
+	.uart_reg = {
+		.sirfsoc_line_ctrl	= 0x0040,
+		.sirfsoc_tx_rx_en	= 0x004c,
+		.sirfsoc_divisor	= 0x0050,
+		.sirfsoc_int_en_reg	= 0x0054,
+		.sirfsoc_int_st_reg	= 0x0058,
+		.sirfsoc_tx_dma_io_ctrl	= 0x0100,
+		.sirfsoc_tx_dma_io_len	= 0x0104,
+		.sirfsoc_tx_fifo_ctrl	= 0x0108,
+		.sirfsoc_tx_fifo_level_chk = 0x010c,
+		.sirfsoc_tx_fifo_op	= 0x0110,
+		.sirfsoc_tx_fifo_status	= 0x0114,
+		.sirfsoc_tx_fifo_data	= 0x0118,
+		.sirfsoc_rx_dma_io_ctrl	= 0x0120,
+		.sirfsoc_rx_dma_io_len	= 0x0124,
+		.sirfsoc_rx_fifo_ctrl	= 0x0128,
+		.sirfsoc_rx_fifo_level_chk = 0x012c,
+		.sirfsoc_rx_fifo_op	= 0x0130,
+		.sirfsoc_rx_fifo_status	= 0x0134,
+		.sirfsoc_rx_fifo_data	= 0x0138,
+		.sirfsoc_afc_ctrl	= 0x0140,
+		.sirfsoc_swh_dma_io	= 0x0148,
+	},
+	.uart_int_en = {
+		.sirfsoc_rx_done_en	= BIT(0),
+		.sirfsoc_tx_done_en	= BIT(1),
+		.sirfsoc_rx_oflow_en	= BIT(2),
+		.sirfsoc_tx_allout_en	= BIT(3),
+		.sirfsoc_rx_io_dma_en	= BIT(4),
+		.sirfsoc_tx_io_dma_en	= BIT(5),
+		.sirfsoc_rxfifo_full_en	= BIT(6),
+		.sirfsoc_txfifo_empty_en = BIT(7),
+		.sirfsoc_rxfifo_thd_en	= BIT(8),
+		.sirfsoc_txfifo_thd_en	= BIT(9),
+		.sirfsoc_frm_err_en	= BIT(10),
+		.sirfsoc_rxd_brk_en	= BIT(11),
+		.sirfsoc_rx_timeout_en	= BIT(12),
+		.sirfsoc_parity_err_en	= BIT(13),
+		.sirfsoc_cts_en		= BIT(14),
+		.sirfsoc_rts_en		= BIT(15),
+	},
+	.uart_int_st = {
+		.sirfsoc_rx_done	= BIT(0),
+		.sirfsoc_tx_done	= BIT(1),
+		.sirfsoc_rx_oflow	= BIT(2),
+		.sirfsoc_tx_allout	= BIT(3),
+		.sirfsoc_rx_io_dma	= BIT(4),
+		.sirfsoc_tx_io_dma	= BIT(5),
+		.sirfsoc_rxfifo_full	= BIT(6),
+		.sirfsoc_txfifo_empty	= BIT(7),
+		.sirfsoc_rxfifo_thd	= BIT(8),
+		.sirfsoc_txfifo_thd	= BIT(9),
+		.sirfsoc_frm_err	= BIT(10),
+		.sirfsoc_rxd_brk	= BIT(11),
+		.sirfsoc_rx_timeout	= BIT(12),
+		.sirfsoc_parity_err	= BIT(13),
+		.sirfsoc_cts		= BIT(14),
+		.sirfsoc_rts		= BIT(15),
+	},
+	.fifo_status = {
+		.ff_full		= uart_ff_full,
+		.ff_empty		= uart_ff_empty,
+	},
+	.uart_param = {
+		.uart_name = "ttySiRF",
+		.port_name = "sirfsoc_uart",
+		.uart_nr = 3,
+		.register_uart_nr = 0,
+	},
+};
+/* uart io ctrl */
 #define SIRFUART_DATA_BIT_LEN_MASK		0x3
 #define SIRFUART_DATA_BIT_LEN_5			BIT(0)
 #define SIRFUART_DATA_BIT_LEN_6			1
@@ -50,96 +279,93 @@
 #define SIRFUART_LOOP_BACK			BIT(7)
 #define SIRFUART_PARITY_MASK			(7 << 3)
 #define SIRFUART_DUMMY_READ			BIT(16)
-
-#define SIRFSOC_UART_RX_TIMEOUT(br, to)	(((br) * (((to) + 999) / 1000)) / 1000)
-#define SIRFUART_RECV_TIMEOUT_MASK	(0xFFFF << 16)
-#define SIRFUART_RECV_TIMEOUT(x)	(((x) & 0xFFFF) << 16)
-
-/* UART Auto Flow Control */
-#define SIRFUART_AFC_RX_THD_MASK		0x000000FF
+#define SIRFUART_AFC_CTRL_RX_THD		0x70
 #define SIRFUART_AFC_RX_EN			BIT(8)
 #define SIRFUART_AFC_TX_EN			BIT(9)
-#define SIRFUART_CTS_CTRL			BIT(10)
-#define SIRFUART_RTS_CTRL			BIT(11)
-#define SIRFUART_CTS_IN_STATUS			BIT(12)
-#define SIRFUART_RTS_OUT_STATUS			BIT(13)
-
-/* UART Interrupt Enable Register */
-#define SIRFUART_RX_DONE_INT			BIT(0)
-#define SIRFUART_TX_DONE_INT			BIT(1)
-#define SIRFUART_RX_OFLOW_INT			BIT(2)
-#define SIRFUART_TX_ALLOUT_INT			BIT(3)
-#define SIRFUART_RX_IO_DMA_INT			BIT(4)
-#define SIRFUART_TX_IO_DMA_INT			BIT(5)
-#define SIRFUART_RXFIFO_FULL_INT		BIT(6)
-#define SIRFUART_TXFIFO_EMPTY_INT		BIT(7)
-#define SIRFUART_RXFIFO_THD_INT			BIT(8)
-#define SIRFUART_TXFIFO_THD_INT			BIT(9)
-#define SIRFUART_FRM_ERR_INT			BIT(10)
-#define SIRFUART_RXD_BREAK_INT			BIT(11)
-#define SIRFUART_RX_TIMEOUT_INT			BIT(12)
-#define SIRFUART_PARITY_ERR_INT			BIT(13)
-#define SIRFUART_CTS_INT_EN			BIT(14)
-#define SIRFUART_RTS_INT_EN			BIT(15)
-
-/* UART Interrupt Status Register */
-#define SIRFUART_RX_DONE			BIT(0)
-#define SIRFUART_TX_DONE			BIT(1)
-#define SIRFUART_RX_OFLOW			BIT(2)
-#define SIRFUART_TX_ALL_EMPTY			BIT(3)
-#define SIRFUART_DMA_IO_RX_DONE			BIT(4)
-#define SIRFUART_DMA_IO_TX_DONE			BIT(5)
-#define SIRFUART_RXFIFO_FULL			BIT(6)
-#define SIRFUART_TXFIFO_EMPTY			BIT(7)
-#define SIRFUART_RXFIFO_THD_REACH		BIT(8)
-#define SIRFUART_TXFIFO_THD_REACH		BIT(9)
-#define SIRFUART_FRM_ERR			BIT(10)
-#define SIRFUART_RXD_BREAK			BIT(11)
-#define SIRFUART_RX_TIMEOUT			BIT(12)
-#define SIRFUART_PARITY_ERR			BIT(13)
-#define SIRFUART_CTS_CHANGE			BIT(14)
-#define SIRFUART_RTS_CHANGE			BIT(15)
-#define SIRFUART_PLUG_IN			BIT(16)
-
-#define SIRFUART_ERR_INT_STAT					\
-				(SIRFUART_RX_OFLOW |		\
-				SIRFUART_FRM_ERR |		\
-				SIRFUART_RXD_BREAK |		\
-				SIRFUART_PARITY_ERR)
-#define SIRFUART_ERR_INT_EN					\
-				(SIRFUART_RX_OFLOW_INT |	\
-				SIRFUART_FRM_ERR_INT |		\
-				SIRFUART_RXD_BREAK_INT |	\
-				SIRFUART_PARITY_ERR_INT)
-#define SIRFUART_TX_INT_EN	SIRFUART_TXFIFO_EMPTY_INT
-#define SIRFUART_RX_IO_INT_EN					\
-				(SIRFUART_RX_TIMEOUT_INT |	\
-				SIRFUART_RXFIFO_THD_INT |	\
-				SIRFUART_RXFIFO_FULL_INT |	\
-				SIRFUART_ERR_INT_EN)
-
+#define SIRFUART_AFC_CTS_CTRL			BIT(10)
+#define SIRFUART_AFC_RTS_CTRL			BIT(11)
+#define	SIRFUART_AFC_CTS_STATUS			BIT(12)
+#define	SIRFUART_AFC_RTS_STATUS			BIT(13)
 /* UART FIFO Register */
-#define SIRFUART_TX_FIFO_STOP			0x0
-#define SIRFUART_TX_FIFO_RESET			0x1
-#define SIRFUART_TX_FIFO_START			0x2
-#define SIRFUART_RX_FIFO_STOP			0x0
-#define SIRFUART_RX_FIFO_RESET			0x1
-#define SIRFUART_RX_FIFO_START			0x2
-#define SIRFUART_TX_MODE_DMA			0
-#define SIRFUART_TX_MODE_IO			1
-#define SIRFUART_RX_MODE_DMA			0
-#define SIRFUART_RX_MODE_IO			1
-
-#define SIRFUART_RX_EN				0x1
-#define SIRFUART_TX_EN				0x2
+#define SIRFUART_FIFO_STOP			0x0
+#define SIRFUART_FIFO_RESET			BIT(0)
+#define SIRFUART_FIFO_START			BIT(1)
 
+#define SIRFUART_RX_EN				BIT(0)
+#define SIRFUART_TX_EN				BIT(1)
+
+#define SIRFUART_IO_MODE			BIT(0)
+#define SIRFUART_DMA_MODE			0x0
+
+/* Macro Specific*/
+#define SIRFUART_INT_EN_CLR                    0x0060
+/* Baud Rate Calculation */
+#define SIRF_MIN_SAMPLE_DIV			0xf
+#define SIRF_MAX_SAMPLE_DIV			0x3f
+#define SIRF_IOCLK_DIV_MAX			0xffff
+#define SIRF_SAMPLE_DIV_SHIFT			16
+#define SIRF_IOCLK_DIV_MASK			0xffff
+#define SIRF_SAMPLE_DIV_MASK			0x3f0000
+#define SIRF_BAUD_RATE_SUPPORT_NR		18
+
+/* USP SPEC */
+#define SIRFSOC_USP_ENDIAN_CTRL_LSBF		BIT(4)
+#define SIRFSOC_USP_EN				BIT(5)
+#define SIRFSOC_USP_MODE2_RXD_DELAY_OFFSET	0
+#define SIRFSOC_USP_MODE2_TXD_DELAY_OFFSET	8
+#define SIRFSOC_USP_MODE2_CLK_DIVISOR_MASK	0x3ff
+#define SIRFSOC_USP_MODE2_CLK_DIVISOR_OFFSET	21
+#define SIRFSOC_USP_TX_DATA_LEN_OFFSET		0
+#define SIRFSOC_USP_TX_SYNC_LEN_OFFSET		8
+#define SIRFSOC_USP_TX_FRAME_LEN_OFFSET		16
+#define SIRFSOC_USP_TX_SHIFTER_LEN_OFFSET	24
+#define SIRFSOC_USP_TX_CLK_DIVISOR_OFFSET	30
+#define SIRFSOC_USP_RX_DATA_LEN_OFFSET		0
+#define SIRFSOC_USP_RX_FRAME_LEN_OFFSET		8
+#define SIRFSOC_USP_RX_SHIFTER_LEN_OFFSET	16
+#define SIRFSOC_USP_RX_CLK_DIVISOR_OFFSET	24
+#define SIRFSOC_USP_ASYNC_DIV2_MASK		0x3f
+#define SIRFSOC_USP_ASYNC_DIV2_OFFSET		16
+
+/* USP-UART Common */
+#define SIRFSOC_UART_RX_TIMEOUT(br, to)	(((br) * (((to) + 999) / 1000)) / 1000)
+#define SIRFUART_RECV_TIMEOUT_VALUE(x)	\
+				(((x) > 0xFFFF) ? 0xFFFF : ((x) & 0xFFFF))
+#define SIRFUART_RECV_TIMEOUT(port, x)	\
+		(((port)->line > 2) ? (x & 0xFFFF) : ((x) & 0xFFFF) << 16)
+
+#define SIRFUART_FIFO_THD(port)		((port->line) == 1 ? 16 : 64)
+#define SIRFUART_ERR_INT_STAT(port, unit_st)			\
+				(uint_st->sirfsoc_rx_oflow |		\
+				uint_st->sirfsoc_frm_err |		\
+				uint_st->sirfsoc_rxd_brk |		\
+		((port->line > 2) ? 0 : uint_st->sirfsoc_parity_err))
+#define SIRFUART_RX_IO_INT_EN(port, uint_en)				\
+				(uint_en->sirfsoc_rx_timeout_en |\
+				 uint_en->sirfsoc_rxfifo_thd_en |\
+				 uint_en->sirfsoc_rxfifo_full_en |\
+				 uint_en->sirfsoc_frm_err_en |\
+				 uint_en->sirfsoc_rx_oflow_en |\
+				 uint_en->sirfsoc_rxd_brk_en |\
+		((port->line > 2) ? 0 : uint_en->sirfsoc_parity_err_en))
+#define SIRFUART_RX_IO_INT_ST(uint_st)				\
+				(uint_st->sirfsoc_rx_timeout |\
+				 uint_st->sirfsoc_rxfifo_thd |\
+				 uint_st->sirfsoc_rxfifo_full)
+#define SIRFUART_CTS_INT_ST(uint_st)	(uint_st->sirfsoc_cts)
+#define SIRFUART_RX_DMA_INT_EN(port, uint_en)				\
+				(uint_en->sirfsoc_rx_timeout_en |\
+				 uint_en->sirfsoc_frm_err_en |\
+				 uint_en->sirfsoc_rx_oflow_en |\
+				 uint_en->sirfsoc_rxd_brk_en |\
+		((port->line > 2) ? 0 : uint_en->sirfsoc_parity_err_en))
 /* Generic Definitions */
 #define SIRFSOC_UART_NAME			"ttySiRF"
 #define SIRFSOC_UART_MAJOR			0
 #define SIRFSOC_UART_MINOR			0
 #define SIRFUART_PORT_NAME			"sirfsoc-uart"
 #define SIRFUART_MAP_SIZE			0x200
-#define SIRFSOC_UART_NR				5
+#define SIRFSOC_UART_NR				6
 #define SIRFSOC_PORT_TYPE			0xa5
 
 /* Baud Rate Calculation */
@@ -151,19 +377,80 @@
 #define SIRF_SAMPLE_DIV_MASK			0x3f0000
 #define SIRF_BAUD_RATE_SUPPORT_NR		18
 
+/* Uart Common Use Macro*/
+#define SIRFSOC_RX_DMA_BUF_SIZE	256
+#define BYTES_TO_ALIGN(dma_addr)	((unsigned long)(dma_addr) & 0x3)
+#define LOOP_DMA_BUFA_FILL	1
+#define LOOP_DMA_BUFB_FILL	2
+#define TX_TRAN_PIO		1
+#define TX_TRAN_DMA		2
+/* Uart Fifo Level Chk */
+#define SIRFUART_TX_FIFO_SC_OFFSET	0
+#define SIRFUART_TX_FIFO_LC_OFFSET	10
+#define SIRFUART_TX_FIFO_HC_OFFSET	20
+#define SIRFUART_TX_FIFO_CHK_SC(line, value) ((((line) == 1) ? (value & 0x3) :\
+				(value & 0x1f)) << SIRFUART_TX_FIFO_SC_OFFSET)
+#define SIRFUART_TX_FIFO_CHK_LC(line, value) ((((line) == 1) ? (value & 0x3) :\
+				(value & 0x1f)) << SIRFUART_TX_FIFO_LC_OFFSET)
+#define SIRFUART_TX_FIFO_CHK_HC(line, value) ((((line) == 1) ? (value & 0x3) :\
+				(value & 0x1f)) << SIRFUART_TX_FIFO_HC_OFFSET)
+
+#define SIRFUART_RX_FIFO_CHK_SC SIRFUART_TX_FIFO_CHK_SC
+#define	SIRFUART_RX_FIFO_CHK_LC SIRFUART_TX_FIFO_CHK_LC
+#define SIRFUART_RX_FIFO_CHK_HC SIRFUART_TX_FIFO_CHK_HC
+/* Indicate how many buffers used */
+#define SIRFSOC_RX_LOOP_BUF_CNT		2
+
+/* Indicate if DMA channel valid */
+#define IS_DMA_CHAN_VALID(x)	((x) != -1)
+#define UNVALID_DMA_CHAN	-1
 /* For Fast Baud Rate Calculation */
 struct sirfsoc_baudrate_to_regv {
 	unsigned int baud_rate;
 	unsigned int reg_val;
 };
 
+enum sirfsoc_tx_state {
+	TX_DMA_IDLE,
+	TX_DMA_RUNNING,
+	TX_DMA_PAUSE,
+};
+
+struct sirfsoc_loop_buffer {
+	struct circ_buf			xmit;
+	dma_cookie_t			cookie;
+	struct dma_async_tx_descriptor	*desc;
+	dma_addr_t			dma_addr;
+};
+
 struct sirfsoc_uart_port {
-	unsigned char			hw_flow_ctrl;
-	unsigned char			ms_enabled;
+	bool				hw_flow_ctrl;
+	bool				ms_enabled;
 
 	struct uart_port		port;
-	struct pinctrl			*p;
 	struct clk			*clk;
+	/* for SiRFmarco, there are SET/CLR for UART_INT_EN */
+	bool				is_marco;
+	struct sirfsoc_uart_register	*uart_reg;
+	int				rx_dma_no;
+	int				tx_dma_no;
+	struct dma_chan			*rx_dma_chan;
+	struct dma_chan			*tx_dma_chan;
+	dma_addr_t			tx_dma_addr;
+	struct dma_async_tx_descriptor	*tx_dma_desc;
+	spinlock_t			rx_lock;
+	spinlock_t			tx_lock;
+	struct tasklet_struct		rx_dma_complete_tasklet;
+	struct tasklet_struct		rx_tmo_process_tasklet;
+	unsigned int			rx_io_count;
+	unsigned long			transfer_size;
+	enum sirfsoc_tx_state		tx_dma_state;
+	unsigned int			cts_gpio;
+	unsigned int			rts_gpio;
+
+	struct sirfsoc_loop_buffer	rx_dma_items[SIRFSOC_RX_LOOP_BUF_CNT];
+	int				rx_completed;
+	int				rx_issued;
 };
 
 /* Hardware Flow Control */
diff --git a/drivers/tty/serial/st-asc.c b/drivers/tty/serial/st-asc.c
new file mode 100644
index 00000000000..21e6e84c0df
--- /dev/null
+++ b/drivers/tty/serial/st-asc.c
@@ -0,0 +1,932 @@
+/*
+ * st-asc.c: ST Asynchronous serial controller (ASC) driver
+ *
+ * Copyright (C) 2003-2013 STMicroelectronics (R&D) Limited
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ */
+
+#if defined(CONFIG_SERIAL_ST_ASC_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
+#define SUPPORT_SYSRQ
+#endif
+
+#include <linux/module.h>
+#include <linux/serial.h>
+#include <linux/console.h>
+#include <linux/sysrq.h>
+#include <linux/platform_device.h>
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/tty.h>
+#include <linux/tty_flip.h>
+#include <linux/delay.h>
+#include <linux/spinlock.h>
+#include <linux/pm_runtime.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/serial_core.h>
+#include <linux/clk.h>
+
+#define DRIVER_NAME "st-asc"
+#define ASC_SERIAL_NAME "ttyAS"
+#define ASC_FIFO_SIZE 16
+#define ASC_MAX_PORTS 8
+
+struct asc_port {
+	struct uart_port port;
+	struct clk *clk;
+	unsigned int hw_flow_control:1;
+	unsigned int force_m1:1;
+};
+
+static struct asc_port asc_ports[ASC_MAX_PORTS];
+static struct uart_driver asc_uart_driver;
+
+/*---- UART Register definitions ------------------------------*/
+
+/* Register offsets */
+
+#define ASC_BAUDRATE			0x00
+#define ASC_TXBUF			0x04
+#define ASC_RXBUF			0x08
+#define ASC_CTL				0x0C
+#define ASC_INTEN			0x10
+#define ASC_STA				0x14
+#define ASC_GUARDTIME			0x18
+#define ASC_TIMEOUT			0x1C
+#define ASC_TXRESET			0x20
+#define ASC_RXRESET			0x24
+#define ASC_RETRIES			0x28
+
+/* ASC_RXBUF */
+#define ASC_RXBUF_PE			0x100
+#define ASC_RXBUF_FE			0x200
+/**
+ * Some of status comes from higher bits of the character and some come from
+ * the status register. Combining both of them in to single status using dummy
+ * bits.
+ */
+#define ASC_RXBUF_DUMMY_RX		0x10000
+#define ASC_RXBUF_DUMMY_BE		0x20000
+#define ASC_RXBUF_DUMMY_OE		0x40000
+
+/* ASC_CTL */
+
+#define ASC_CTL_MODE_MSK		0x0007
+#define  ASC_CTL_MODE_8BIT		0x0001
+#define  ASC_CTL_MODE_7BIT_PAR		0x0003
+#define  ASC_CTL_MODE_9BIT		0x0004
+#define  ASC_CTL_MODE_8BIT_WKUP		0x0005
+#define  ASC_CTL_MODE_8BIT_PAR		0x0007
+#define ASC_CTL_STOP_MSK		0x0018
+#define  ASC_CTL_STOP_HALFBIT		0x0000
+#define  ASC_CTL_STOP_1BIT		0x0008
+#define  ASC_CTL_STOP_1_HALFBIT		0x0010
+#define  ASC_CTL_STOP_2BIT		0x0018
+#define ASC_CTL_PARITYODD		0x0020
+#define ASC_CTL_LOOPBACK		0x0040
+#define ASC_CTL_RUN			0x0080
+#define ASC_CTL_RXENABLE		0x0100
+#define ASC_CTL_SCENABLE		0x0200
+#define ASC_CTL_FIFOENABLE		0x0400
+#define ASC_CTL_CTSENABLE		0x0800
+#define ASC_CTL_BAUDMODE		0x1000
+
+/* ASC_GUARDTIME */
+
+#define ASC_GUARDTIME_MSK		0x00FF
+
+/* ASC_INTEN */
+
+#define ASC_INTEN_RBE			0x0001
+#define ASC_INTEN_TE			0x0002
+#define ASC_INTEN_THE			0x0004
+#define ASC_INTEN_PE			0x0008
+#define ASC_INTEN_FE			0x0010
+#define ASC_INTEN_OE			0x0020
+#define ASC_INTEN_TNE			0x0040
+#define ASC_INTEN_TOI			0x0080
+#define ASC_INTEN_RHF			0x0100
+
+/* ASC_RETRIES */
+
+#define ASC_RETRIES_MSK			0x00FF
+
+/* ASC_RXBUF */
+
+#define ASC_RXBUF_MSK			0x03FF
+
+/* ASC_STA */
+
+#define ASC_STA_RBF			0x0001
+#define ASC_STA_TE			0x0002
+#define ASC_STA_THE			0x0004
+#define ASC_STA_PE			0x0008
+#define ASC_STA_FE			0x0010
+#define ASC_STA_OE			0x0020
+#define ASC_STA_TNE			0x0040
+#define ASC_STA_TOI			0x0080
+#define ASC_STA_RHF			0x0100
+#define ASC_STA_TF			0x0200
+#define ASC_STA_NKD			0x0400
+
+/* ASC_TIMEOUT */
+
+#define ASC_TIMEOUT_MSK			0x00FF
+
+/* ASC_TXBUF */
+
+#define ASC_TXBUF_MSK			0x01FF
+
+/*---- Inline function definitions ---------------------------*/
+
+static inline struct asc_port *to_asc_port(struct uart_port *port)
+{
+	return container_of(port, struct asc_port, port);
+}
+
+static inline u32 asc_in(struct uart_port *port, u32 offset)
+{
+	return readl(port->membase + offset);
+}
+
+static inline void asc_out(struct uart_port *port, u32 offset, u32 value)
+{
+	writel(value, port->membase + offset);
+}
+
+/*
+ * Some simple utility functions to enable and disable interrupts.
+ * Note that these need to be called with interrupts disabled.
+ */
+static inline void asc_disable_tx_interrupts(struct uart_port *port)
+{
+	u32 intenable = asc_in(port, ASC_INTEN) & ~ASC_INTEN_THE;
+	asc_out(port, ASC_INTEN, intenable);
+	(void)asc_in(port, ASC_INTEN);	/* Defeat bus write posting */
+}
+
+static inline void asc_enable_tx_interrupts(struct uart_port *port)
+{
+	u32 intenable = asc_in(port, ASC_INTEN) | ASC_INTEN_THE;
+	asc_out(port, ASC_INTEN, intenable);
+}
+
+static inline void asc_disable_rx_interrupts(struct uart_port *port)
+{
+	u32 intenable = asc_in(port, ASC_INTEN) & ~ASC_INTEN_RBE;
+	asc_out(port, ASC_INTEN, intenable);
+	(void)asc_in(port, ASC_INTEN);	/* Defeat bus write posting */
+}
+
+static inline void asc_enable_rx_interrupts(struct uart_port *port)
+{
+	u32 intenable = asc_in(port, ASC_INTEN) | ASC_INTEN_RBE;
+	asc_out(port, ASC_INTEN, intenable);
+}
+
+static inline u32 asc_txfifo_is_empty(struct uart_port *port)
+{
+	return asc_in(port, ASC_STA) & ASC_STA_TE;
+}
+
+static inline int asc_txfifo_is_full(struct uart_port *port)
+{
+	return asc_in(port, ASC_STA) & ASC_STA_TF;
+}
+
+static inline const char *asc_port_name(struct uart_port *port)
+{
+	return to_platform_device(port->dev)->name;
+}
+
+/*----------------------------------------------------------------------*/
+
+/*
+ * This section contains code to support the use of the ASC as a
+ * generic serial port.
+ */
+
+static inline unsigned asc_hw_txroom(struct uart_port *port)
+{
+	u32 status = asc_in(port, ASC_STA);
+
+	if (status & ASC_STA_THE)
+		return port->fifosize / 2;
+	else if (!(status & ASC_STA_TF))
+		return 1;
+
+	return 0;
+}
+
+/*
+ * Start transmitting chars.
+ * This is called from both interrupt and task level.
+ * Either way interrupts are disabled.
+ */
+static void asc_transmit_chars(struct uart_port *port)
+{
+	struct circ_buf *xmit = &port->state->xmit;
+	int txroom;
+	unsigned char c;
+
+	txroom = asc_hw_txroom(port);
+
+	if ((txroom != 0) && port->x_char) {
+		c = port->x_char;
+		port->x_char = 0;
+		asc_out(port, ASC_TXBUF, c);
+		port->icount.tx++;
+		txroom = asc_hw_txroom(port);
+	}
+
+	if (uart_tx_stopped(port)) {
+		/*
+		 * We should try and stop the hardware here, but I
+		 * don't think the ASC has any way to do that.
+		 */
+		asc_disable_tx_interrupts(port);
+		return;
+	}
+
+	if (uart_circ_empty(xmit)) {
+		asc_disable_tx_interrupts(port);
+		return;
+	}
+
+	if (txroom == 0)
+		return;
+
+	do {
+		c = xmit->buf[xmit->tail];
+		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
+		asc_out(port, ASC_TXBUF, c);
+		port->icount.tx++;
+		txroom--;
+	} while ((txroom > 0) && (!uart_circ_empty(xmit)));
+
+	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+		uart_write_wakeup(port);
+
+	if (uart_circ_empty(xmit))
+		asc_disable_tx_interrupts(port);
+}
+
+static void asc_receive_chars(struct uart_port *port)
+{
+	struct tty_port *tport = &port->state->port;
+	unsigned long status;
+	unsigned long c = 0;
+	char flag;
+
+	if (port->irq_wake)
+		pm_wakeup_event(tport->tty->dev, 0);
+
+	while ((status = asc_in(port, ASC_STA)) & ASC_STA_RBF) {
+		c = asc_in(port, ASC_RXBUF) | ASC_RXBUF_DUMMY_RX;
+		flag = TTY_NORMAL;
+		port->icount.rx++;
+
+		if ((c & (ASC_RXBUF_FE | ASC_RXBUF_PE)) ||
+			status & ASC_STA_OE) {
+
+			if (c & ASC_RXBUF_FE) {
+				if (c == ASC_RXBUF_FE) {
+					port->icount.brk++;
+					if (uart_handle_break(port))
+						continue;
+					c |= ASC_RXBUF_DUMMY_BE;
+				} else {
+					port->icount.frame++;
+				}
+			} else if (c & ASC_RXBUF_PE) {
+				port->icount.parity++;
+			}
+			/*
+			 * Reading any data from the RX FIFO clears the
+			 * overflow error condition.
+			 */
+			if (status & ASC_STA_OE) {
+				port->icount.overrun++;
+				c |= ASC_RXBUF_DUMMY_OE;
+			}
+
+			c &= port->read_status_mask;
+
+			if (c & ASC_RXBUF_DUMMY_BE)
+				flag = TTY_BREAK;
+			else if (c & ASC_RXBUF_PE)
+				flag = TTY_PARITY;
+			else if (c & ASC_RXBUF_FE)
+				flag = TTY_FRAME;
+		}
+
+		if (uart_handle_sysrq_char(port, c))
+			continue;
+
+		uart_insert_char(port, c, ASC_RXBUF_DUMMY_OE, c & 0xff, flag);
+	}
+
+	/* Tell the rest of the system the news. New characters! */
+	tty_flip_buffer_push(tport);
+}
+
+static irqreturn_t asc_interrupt(int irq, void *ptr)
+{
+	struct uart_port *port = ptr;
+	u32 status;
+
+	spin_lock(&port->lock);
+
+	status = asc_in(port, ASC_STA);
+
+	if (status & ASC_STA_RBF) {
+		/* Receive FIFO not empty */
+		asc_receive_chars(port);
+	}
+
+	if ((status & ASC_STA_THE) &&
+	    (asc_in(port, ASC_INTEN) & ASC_INTEN_THE)) {
+		/* Transmitter FIFO at least half empty */
+		asc_transmit_chars(port);
+	}
+
+	spin_unlock(&port->lock);
+
+	return IRQ_HANDLED;
+}
+
+/*----------------------------------------------------------------------*/
+
+/*
+ * UART Functions
+ */
+
+static unsigned int asc_tx_empty(struct uart_port *port)
+{
+	return asc_txfifo_is_empty(port) ? TIOCSER_TEMT : 0;
+}
+
+static void asc_set_mctrl(struct uart_port *port, unsigned int mctrl)
+{
+	/*
+	 * This routine is used for seting signals of: DTR, DCD, CTS/RTS
+	 * We use ASC's hardware for CTS/RTS, so don't need any for that.
+	 * Some boards have DTR and DCD implemented using PIO pins,
+	 * code to do this should be hooked in here.
+	 */
+}
+
+static unsigned int asc_get_mctrl(struct uart_port *port)
+{
+	/*
+	 * This routine is used for geting signals of: DTR, DCD, DSR, RI,
+	 * and CTS/RTS
+	 */
+	return TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
+}
+
+/* There are probably characters waiting to be transmitted. */
+static void asc_start_tx(struct uart_port *port)
+{
+	struct circ_buf *xmit = &port->state->xmit;
+
+	if (!uart_circ_empty(xmit))
+		asc_enable_tx_interrupts(port);
+}
+
+/* Transmit stop */
+static void asc_stop_tx(struct uart_port *port)
+{
+	asc_disable_tx_interrupts(port);
+}
+
+/* Receive stop */
+static void asc_stop_rx(struct uart_port *port)
+{
+	asc_disable_rx_interrupts(port);
+}
+
+/* Force modem status interrupts on */
+static void asc_enable_ms(struct uart_port *port)
+{
+	/* Nothing here yet .. */
+}
+
+/* Handle breaks - ignored by us */
+static void asc_break_ctl(struct uart_port *port, int break_state)
+{
+	/* Nothing here yet .. */
+}
+
+/*
+ * Enable port for reception.
+ */
+static int asc_startup(struct uart_port *port)
+{
+	if (request_irq(port->irq, asc_interrupt, IRQF_NO_SUSPEND,
+			asc_port_name(port), port)) {
+		dev_err(port->dev, "cannot allocate irq.\n");
+		return -ENODEV;
+	}
+
+	asc_transmit_chars(port);
+	asc_enable_rx_interrupts(port);
+
+	return 0;
+}
+
+static void asc_shutdown(struct uart_port *port)
+{
+	asc_disable_tx_interrupts(port);
+	asc_disable_rx_interrupts(port);
+	free_irq(port->irq, port);
+}
+
+static void asc_pm(struct uart_port *port, unsigned int state,
+		unsigned int oldstate)
+{
+	struct asc_port *ascport = to_asc_port(port);
+	unsigned long flags = 0;
+	u32 ctl;
+
+	switch (state) {
+	case UART_PM_STATE_ON:
+		clk_prepare_enable(ascport->clk);
+		break;
+	case UART_PM_STATE_OFF:
+		/*
+		 * Disable the ASC baud rate generator, which is as close as
+		 * we can come to turning it off. Note this is not called with
+		 * the port spinlock held.
+		 */
+		spin_lock_irqsave(&port->lock, flags);
+		ctl = asc_in(port, ASC_CTL) & ~ASC_CTL_RUN;
+		asc_out(port, ASC_CTL, ctl);
+		spin_unlock_irqrestore(&port->lock, flags);
+		clk_disable_unprepare(ascport->clk);
+		break;
+	}
+}
+
+static void asc_set_termios(struct uart_port *port, struct ktermios *termios,
+			    struct ktermios *old)
+{
+	struct asc_port *ascport = to_asc_port(port);
+	unsigned int baud;
+	u32 ctrl_val;
+	tcflag_t cflag;
+	unsigned long flags;
+
+	/* Update termios to reflect hardware capabilities */
+	termios->c_cflag &= ~(CMSPAR |
+			 (ascport->hw_flow_control ? 0 : CRTSCTS));
+
+	port->uartclk = clk_get_rate(ascport->clk);
+
+	baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
+	cflag = termios->c_cflag;
+
+	spin_lock_irqsave(&port->lock, flags);
+
+	/* read control register */
+	ctrl_val = asc_in(port, ASC_CTL);
+
+	/* stop serial port and reset value */
+	asc_out(port, ASC_CTL, (ctrl_val & ~ASC_CTL_RUN));
+	ctrl_val = ASC_CTL_RXENABLE | ASC_CTL_FIFOENABLE;
+
+	/* reset fifo rx & tx */
+	asc_out(port, ASC_TXRESET, 1);
+	asc_out(port, ASC_RXRESET, 1);
+
+	/* set character length */
+	if ((cflag & CSIZE) == CS7) {
+		ctrl_val |= ASC_CTL_MODE_7BIT_PAR;
+	} else {
+		ctrl_val |= (cflag & PARENB) ?  ASC_CTL_MODE_8BIT_PAR :
+						ASC_CTL_MODE_8BIT;
+	}
+
+	/* set stop bit */
+	ctrl_val |= (cflag & CSTOPB) ? ASC_CTL_STOP_2BIT : ASC_CTL_STOP_1BIT;
+
+	/* odd parity */
+	if (cflag & PARODD)
+		ctrl_val |= ASC_CTL_PARITYODD;
+
+	/* hardware flow control */
+	if ((cflag & CRTSCTS))
+		ctrl_val |= ASC_CTL_CTSENABLE;
+
+	if ((baud < 19200) && !ascport->force_m1) {
+		asc_out(port, ASC_BAUDRATE, (port->uartclk / (16 * baud)));
+	} else {
+		/*
+		 * MODE 1: recommended for high bit rates (above 19.2K)
+		 *
+		 *                   baudrate * 16 * 2^16
+		 * ASCBaudRate =   ------------------------
+		 *                          inputclock
+		 *
+		 * However to keep the maths inside 32bits we divide top and
+		 * bottom by 64. The +1 is to avoid a divide by zero if the
+		 * input clock rate is something unexpected.
+		 */
+		u32 counter = (baud * 16384) / ((port->uartclk / 64) + 1);
+		asc_out(port, ASC_BAUDRATE, counter);
+		ctrl_val |= ASC_CTL_BAUDMODE;
+	}
+
+	uart_update_timeout(port, cflag, baud);
+
+	ascport->port.read_status_mask = ASC_RXBUF_DUMMY_OE;
+	if (termios->c_iflag & INPCK)
+		ascport->port.read_status_mask |= ASC_RXBUF_FE | ASC_RXBUF_PE;
+	if (termios->c_iflag & (BRKINT | PARMRK))
+		ascport->port.read_status_mask |= ASC_RXBUF_DUMMY_BE;
+
+	/*
+	 * Characters to ignore
+	 */
+	ascport->port.ignore_status_mask = 0;
+	if (termios->c_iflag & IGNPAR)
+		ascport->port.ignore_status_mask |= ASC_RXBUF_FE | ASC_RXBUF_PE;
+	if (termios->c_iflag & IGNBRK) {
+		ascport->port.ignore_status_mask |= ASC_RXBUF_DUMMY_BE;
+		/*
+		 * If we're ignoring parity and break indicators,
+		 * ignore overruns too (for real raw support).
+		 */
+		if (termios->c_iflag & IGNPAR)
+			ascport->port.ignore_status_mask |= ASC_RXBUF_DUMMY_OE;
+	}
+
+	/*
+	 * Ignore all characters if CREAD is not set.
+	 */
+	if (!(termios->c_cflag & CREAD))
+		ascport->port.ignore_status_mask |= ASC_RXBUF_DUMMY_RX;
+
+	/* Set the timeout */
+	asc_out(port, ASC_TIMEOUT, 20);
+
+	/* write final value and enable port */
+	asc_out(port, ASC_CTL, (ctrl_val | ASC_CTL_RUN));
+
+	spin_unlock_irqrestore(&port->lock, flags);
+}
+
+static const char *asc_type(struct uart_port *port)
+{
+	return (port->type == PORT_ASC) ? DRIVER_NAME : NULL;
+}
+
+static void asc_release_port(struct uart_port *port)
+{
+}
+
+static int asc_request_port(struct uart_port *port)
+{
+	return 0;
+}
+
+/*
+ * Called when the port is opened, and UPF_BOOT_AUTOCONF flag is set
+ * Set type field if successful
+ */
+static void asc_config_port(struct uart_port *port, int flags)
+{
+	if ((flags & UART_CONFIG_TYPE))
+		port->type = PORT_ASC;
+}
+
+static int
+asc_verify_port(struct uart_port *port, struct serial_struct *ser)
+{
+	/* No user changeable parameters */
+	return -EINVAL;
+}
+
+#ifdef CONFIG_CONSOLE_POLL
+/*
+ * Console polling routines for writing and reading from the uart while
+ * in an interrupt or debug context (i.e. kgdb).
+ */
+
+static int asc_get_poll_char(struct uart_port *port)
+{
+	if (!(asc_in(port, ASC_STA) & ASC_STA_RBF))
+		return NO_POLL_CHAR;
+
+	return asc_in(port, ASC_RXBUF);
+}
+
+static void asc_put_poll_char(struct uart_port *port, unsigned char c)
+{
+	while (asc_txfifo_is_full(port))
+		cpu_relax();
+	asc_out(port, ASC_TXBUF, c);
+}
+
+#endif /* CONFIG_CONSOLE_POLL */
+
+/*---------------------------------------------------------------------*/
+
+static struct uart_ops asc_uart_ops = {
+	.tx_empty	= asc_tx_empty,
+	.set_mctrl	= asc_set_mctrl,
+	.get_mctrl	= asc_get_mctrl,
+	.start_tx	= asc_start_tx,
+	.stop_tx	= asc_stop_tx,
+	.stop_rx	= asc_stop_rx,
+	.enable_ms	= asc_enable_ms,
+	.break_ctl	= asc_break_ctl,
+	.startup	= asc_startup,
+	.shutdown	= asc_shutdown,
+	.set_termios	= asc_set_termios,
+	.type		= asc_type,
+	.release_port	= asc_release_port,
+	.request_port	= asc_request_port,
+	.config_port	= asc_config_port,
+	.verify_port	= asc_verify_port,
+	.pm		= asc_pm,
+#ifdef CONFIG_CONSOLE_POLL
+	.poll_get_char = asc_get_poll_char,
+	.poll_put_char = asc_put_poll_char,
+#endif /* CONFIG_CONSOLE_POLL */
+};
+
+static int asc_init_port(struct asc_port *ascport,
+			  struct platform_device *pdev)
+{
+	struct uart_port *port = &ascport->port;
+	struct resource *res;
+
+	port->iotype	= UPIO_MEM;
+	port->flags	= UPF_BOOT_AUTOCONF;
+	port->ops	= &asc_uart_ops;
+	port->fifosize	= ASC_FIFO_SIZE;
+	port->dev	= &pdev->dev;
+	port->irq	= platform_get_irq(pdev, 0);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	port->membase = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(port->membase))
+		return PTR_ERR(port->membase);
+	port->mapbase = res->start;
+
+	spin_lock_init(&port->lock);
+
+	ascport->clk = devm_clk_get(&pdev->dev, NULL);
+
+	if (WARN_ON(IS_ERR(ascport->clk)))
+		return -EINVAL;
+	/* ensure that clk rate is correct by enabling the clk */
+	clk_prepare_enable(ascport->clk);
+	ascport->port.uartclk = clk_get_rate(ascport->clk);
+	WARN_ON(ascport->port.uartclk == 0);
+	clk_disable_unprepare(ascport->clk);
+
+	return 0;
+}
+
+static struct asc_port *asc_of_get_asc_port(struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	int id;
+
+	if (!np)
+		return NULL;
+
+	id = of_alias_get_id(np, ASC_SERIAL_NAME);
+
+	if (id < 0)
+		id = 0;
+
+	if (WARN_ON(id >= ASC_MAX_PORTS))
+		return NULL;
+
+	asc_ports[id].hw_flow_control = of_property_read_bool(np,
+							"st,hw-flow-control");
+	asc_ports[id].force_m1 =  of_property_read_bool(np, "st,force_m1");
+	asc_ports[id].port.line = id;
+	return &asc_ports[id];
+}
+
+#ifdef CONFIG_OF
+static struct of_device_id asc_match[] = {
+	{ .compatible = "st,asc", },
+	{},
+};
+
+MODULE_DEVICE_TABLE(of, asc_match);
+#endif
+
+static int asc_serial_probe(struct platform_device *pdev)
+{
+	int ret;
+	struct asc_port *ascport;
+
+	ascport = asc_of_get_asc_port(pdev);
+	if (!ascport)
+		return -ENODEV;
+
+	ret = asc_init_port(ascport, pdev);
+	if (ret)
+		return ret;
+
+	ret = uart_add_one_port(&asc_uart_driver, &ascport->port);
+	if (ret)
+		return ret;
+
+	platform_set_drvdata(pdev, &ascport->port);
+
+	return 0;
+}
+
+static int asc_serial_remove(struct platform_device *pdev)
+{
+	struct uart_port *port = platform_get_drvdata(pdev);
+
+	return uart_remove_one_port(&asc_uart_driver, port);
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int asc_serial_suspend(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct uart_port *port = platform_get_drvdata(pdev);
+
+	return uart_suspend_port(&asc_uart_driver, port);
+}
+
+static int asc_serial_resume(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct uart_port *port = platform_get_drvdata(pdev);
+
+	return uart_resume_port(&asc_uart_driver, port);
+}
+
+#endif /* CONFIG_PM_SLEEP */
+
+/*----------------------------------------------------------------------*/
+
+#ifdef CONFIG_SERIAL_ST_ASC_CONSOLE
+static void asc_console_putchar(struct uart_port *port, int ch)
+{
+	unsigned int timeout = 1000000;
+
+	/* Wait for upto 1 second in case flow control is stopping us. */
+	while (--timeout && asc_txfifo_is_full(port))
+		udelay(1);
+
+	asc_out(port, ASC_TXBUF, ch);
+}
+
+/*
+ *  Print a string to the serial port trying not to disturb
+ *  any possible real use of the port...
+ */
+
+static void asc_console_write(struct console *co, const char *s, unsigned count)
+{
+	struct uart_port *port = &asc_ports[co->index].port;
+	unsigned long flags;
+	unsigned long timeout = 1000000;
+	int locked = 1;
+	u32 intenable;
+
+	local_irq_save(flags);
+	if (port->sysrq)
+		locked = 0; /* asc_interrupt has already claimed the lock */
+	else if (oops_in_progress)
+		locked = spin_trylock(&port->lock);
+	else
+		spin_lock(&port->lock);
+
+	/*
+	 * Disable interrupts so we don't get the IRQ line bouncing
+	 * up and down while interrupts are disabled.
+	 */
+	intenable = asc_in(port, ASC_INTEN);
+	asc_out(port, ASC_INTEN, 0);
+	(void)asc_in(port, ASC_INTEN);	/* Defeat bus write posting */
+
+	uart_console_write(port, s, count, asc_console_putchar);
+
+	while (--timeout && !asc_txfifo_is_empty(port))
+		udelay(1);
+
+	asc_out(port, ASC_INTEN, intenable);
+
+	if (locked)
+		spin_unlock(&port->lock);
+	local_irq_restore(flags);
+}
+
+static int asc_console_setup(struct console *co, char *options)
+{
+	struct asc_port *ascport;
+	int baud = 9600;
+	int bits = 8;
+	int parity = 'n';
+	int flow = 'n';
+
+	if (co->index >= ASC_MAX_PORTS)
+		return -ENODEV;
+
+	ascport = &asc_ports[co->index];
+
+	/*
+	 * This driver does not support early console initialization
+	 * (use ARM early printk support instead), so we only expect
+	 * this to be called during the uart port registration when the
+	 * driver gets probed and the port should be mapped at that point.
+	 */
+	BUG_ON(ascport->port.mapbase == 0 || ascport->port.membase == NULL);
+
+	if (options)
+		uart_parse_options(options, &baud, &parity, &bits, &flow);
+
+	return uart_set_options(&ascport->port, co, baud, parity, bits, flow);
+}
+
+static struct console asc_console = {
+	.name		= ASC_SERIAL_NAME,
+	.device		= uart_console_device,
+	.write		= asc_console_write,
+	.setup		= asc_console_setup,
+	.flags		= CON_PRINTBUFFER,
+	.index		= -1,
+	.data		= &asc_uart_driver,
+};
+
+#define ASC_SERIAL_CONSOLE (&asc_console)
+
+#else
+#define ASC_SERIAL_CONSOLE NULL
+#endif /* CONFIG_SERIAL_ST_ASC_CONSOLE */
+
+static struct uart_driver asc_uart_driver = {
+	.owner		= THIS_MODULE,
+	.driver_name	= DRIVER_NAME,
+	.dev_name	= ASC_SERIAL_NAME,
+	.major		= 0,
+	.minor		= 0,
+	.nr		= ASC_MAX_PORTS,
+	.cons		= ASC_SERIAL_CONSOLE,
+};
+
+static const struct dev_pm_ops asc_serial_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(asc_serial_suspend, asc_serial_resume)
+};
+
+static struct platform_driver asc_serial_driver = {
+	.probe		= asc_serial_probe,
+	.remove		= asc_serial_remove,
+	.driver	= {
+		.name	= DRIVER_NAME,
+		.pm	= &asc_serial_pm_ops,
+		.owner	= THIS_MODULE,
+		.of_match_table = of_match_ptr(asc_match),
+	},
+};
+
+static int __init asc_init(void)
+{
+	int ret;
+	static char banner[] __initdata =
+		KERN_INFO "STMicroelectronics ASC driver initialized\n";
+
+	printk(banner);
+
+	ret = uart_register_driver(&asc_uart_driver);
+	if (ret)
+		return ret;
+
+	ret = platform_driver_register(&asc_serial_driver);
+	if (ret)
+		uart_unregister_driver(&asc_uart_driver);
+
+	return ret;
+}
+
+static void __exit asc_exit(void)
+{
+	platform_driver_unregister(&asc_serial_driver);
+	uart_unregister_driver(&asc_uart_driver);
+}
+
+module_init(asc_init);
+module_exit(asc_exit);
+
+MODULE_ALIAS("platform:" DRIVER_NAME);
+MODULE_AUTHOR("STMicroelectronics (R&D) Limited");
+MODULE_DESCRIPTION("STMicroelectronics ASC serial port driver");
+MODULE_LICENSE("GPL");
diff --git a/drivers/tty/serial/timbuart.c b/drivers/tty/serial/timbuart.c
index 6818410a2be..f87097acd8a 100644
--- a/drivers/tty/serial/timbuart.c
+++ b/drivers/tty/serial/timbuart.c
@@ -162,7 +162,7 @@ static void timbuart_handle_tx_port(struct uart_port *port, u32 isr, u32 *ier)
 	dev_dbg(port->dev, "%s - leaving\n", __func__);
 }
 
-void timbuart_handle_rx_port(struct uart_port *port, u32 isr, u32 *ier)
+static void timbuart_handle_rx_port(struct uart_port *port, u32 isr, u32 *ier)
 {
 	if (isr & RXFLAGS) {
 		/* Some RX status is set */
@@ -184,7 +184,7 @@ void timbuart_handle_rx_port(struct uart_port *port, u32 isr, u32 *ier)
 	dev_dbg(port->dev, "%s - leaving\n", __func__);
 }
 
-void timbuart_tasklet(unsigned long arg)
+static void timbuart_tasklet(unsigned long arg)
 {
 	struct timbuart_port *uart = (struct timbuart_port *)arg;
 	u32 isr, ier = 0;
diff --git a/drivers/tty/serial/vr41xx_siu.c b/drivers/tty/serial/vr41xx_siu.c
index f655997f44a..a63c14bc9a2 100644
--- a/drivers/tty/serial/vr41xx_siu.c
+++ b/drivers/tty/serial/vr41xx_siu.c
@@ -705,7 +705,7 @@ static int siu_init_ports(struct platform_device *pdev)
 {
 	struct uart_port *port;
 	struct resource *res;
-	int *type = pdev->dev.platform_data;
+	int *type = dev_get_platdata(&pdev->dev);
 	int i;
 
 	if (!type)
diff --git a/drivers/tty/serial/vt8500_serial.c b/drivers/tty/serial/vt8500_serial.c
index 48af43de346..93b697a0de6 100644
--- a/drivers/tty/serial/vt8500_serial.c
+++ b/drivers/tty/serial/vt8500_serial.c
@@ -170,7 +170,9 @@ static void handle_rx(struct uart_port *port)
 			tty_insert_flip_char(tport, c, flag);
 	}
 
+	spin_unlock(&port->lock);
 	tty_flip_buffer_push(tport);
+	spin_lock(&port->lock);
 }
 
 static void handle_tx(struct uart_port *port)
@@ -630,7 +632,6 @@ static int vt8500_serial_remove(struct platform_device *pdev)
 {
 	struct vt8500_port *vt8500_port = platform_get_drvdata(pdev);
 
-	platform_set_drvdata(pdev, NULL);
 	clk_disable_unprepare(vt8500_port->clk);
 	uart_remove_one_port(&vt8500_uart_driver, &vt8500_port->uart);
 
diff --git a/drivers/tty/synclink.c b/drivers/tty/synclink.c
index 8eaf1ab8add..e1ce141bad5 100644
--- a/drivers/tty/synclink.c
+++ b/drivers/tty/synclink.c
@@ -577,22 +577,22 @@ struct mgsl_struct {
 
 #define SICR_RXC_ACTIVE			BIT15
 #define SICR_RXC_INACTIVE		BIT14
-#define SICR_RXC			(BIT15+BIT14)
+#define SICR_RXC			(BIT15|BIT14)
 #define SICR_TXC_ACTIVE			BIT13
 #define SICR_TXC_INACTIVE		BIT12
-#define SICR_TXC			(BIT13+BIT12)
+#define SICR_TXC			(BIT13|BIT12)
 #define SICR_RI_ACTIVE			BIT11
 #define SICR_RI_INACTIVE		BIT10
-#define SICR_RI				(BIT11+BIT10)
+#define SICR_RI				(BIT11|BIT10)
 #define SICR_DSR_ACTIVE			BIT9
 #define SICR_DSR_INACTIVE		BIT8
-#define SICR_DSR			(BIT9+BIT8)
+#define SICR_DSR			(BIT9|BIT8)
 #define SICR_DCD_ACTIVE			BIT7
 #define SICR_DCD_INACTIVE		BIT6
-#define SICR_DCD			(BIT7+BIT6)
+#define SICR_DCD			(BIT7|BIT6)
 #define SICR_CTS_ACTIVE			BIT5
 #define SICR_CTS_INACTIVE		BIT4
-#define SICR_CTS			(BIT5+BIT4)
+#define SICR_CTS			(BIT5|BIT4)
 #define SICR_RCC_UNDERFLOW		BIT3
 #define SICR_DPLL_NO_SYNC		BIT2
 #define SICR_BRG1_ZERO			BIT1
@@ -1161,7 +1161,7 @@ static void mgsl_isr_receive_status( struct mgsl_struct *info )
 {
 	u16 status = usc_InReg( info, RCSR );
 
-	if ( debug_level >= DEBUG_LEVEL_ISR )	
+	if ( debug_level >= DEBUG_LEVEL_ISR )
 		printk("%s(%d):mgsl_isr_receive_status status=%04X\n",
 			__FILE__,__LINE__,status);
 			
@@ -1181,7 +1181,7 @@ static void mgsl_isr_receive_status( struct mgsl_struct *info )
  			(usc_InReg(info, RICR) & ~RXSTATUS_ABORT_RECEIVED));
  	}
 
-	if (status & (RXSTATUS_EXITED_HUNT + RXSTATUS_IDLE_RECEIVED)) {
+	if (status & (RXSTATUS_EXITED_HUNT | RXSTATUS_IDLE_RECEIVED)) {
 		if (status & RXSTATUS_EXITED_HUNT)
 			info->icount.exithunt++;
 		if (status & RXSTATUS_IDLE_RECEIVED)
@@ -1463,21 +1463,21 @@ static void mgsl_isr_receive_data( struct mgsl_struct *info )
 
 		/* get the status of the received byte */
 		status = usc_InReg(info, RCSR);
-		if ( status & (RXSTATUS_FRAMING_ERROR + RXSTATUS_PARITY_ERROR +
-				RXSTATUS_OVERRUN + RXSTATUS_BREAK_RECEIVED) )
+		if ( status & (RXSTATUS_FRAMING_ERROR | RXSTATUS_PARITY_ERROR |
+				RXSTATUS_OVERRUN | RXSTATUS_BREAK_RECEIVED) )
 			usc_UnlatchRxstatusBits(info,RXSTATUS_ALL);
 		
 		icount->rx++;
 		
 		flag = 0;
-		if ( status & (RXSTATUS_FRAMING_ERROR + RXSTATUS_PARITY_ERROR +
-				RXSTATUS_OVERRUN + RXSTATUS_BREAK_RECEIVED) ) {
-			printk("rxerr=%04X\n",status);					
+		if ( status & (RXSTATUS_FRAMING_ERROR | RXSTATUS_PARITY_ERROR |
+				RXSTATUS_OVERRUN | RXSTATUS_BREAK_RECEIVED) ) {
+			printk("rxerr=%04X\n",status);
 			/* update error statistics */
 			if ( status & RXSTATUS_BREAK_RECEIVED ) {
-				status &= ~(RXSTATUS_FRAMING_ERROR + RXSTATUS_PARITY_ERROR);
+				status &= ~(RXSTATUS_FRAMING_ERROR | RXSTATUS_PARITY_ERROR);
 				icount->brk++;
-			} else if (status & RXSTATUS_PARITY_ERROR) 
+			} else if (status & RXSTATUS_PARITY_ERROR)
 				icount->parity++;
 			else if (status & RXSTATUS_FRAMING_ERROR)
 				icount->frame++;
@@ -1488,7 +1488,7 @@ static void mgsl_isr_receive_data( struct mgsl_struct *info )
 				icount->overrun++;
 			}
 
-			/* discard char if tty control flags say so */					
+			/* discard char if tty control flags say so */
 			if (status & info->ignore_status_mask)
 				continue;
 				
@@ -1545,8 +1545,8 @@ static void mgsl_isr_misc( struct mgsl_struct *info )
 		usc_EnableReceiver(info,DISABLE_UNCONDITIONAL);
 		usc_DmaCmd(info, DmaCmd_ResetRxChannel);
 		usc_UnlatchRxstatusBits(info, RXSTATUS_ALL);
-		usc_ClearIrqPendingBits(info, RECEIVE_DATA + RECEIVE_STATUS);
-		usc_DisableInterrupts(info, RECEIVE_DATA + RECEIVE_STATUS);
+		usc_ClearIrqPendingBits(info, RECEIVE_DATA | RECEIVE_STATUS);
+		usc_DisableInterrupts(info, RECEIVE_DATA | RECEIVE_STATUS);
 
 		/* schedule BH handler to restart receiver */
 		info->pending_bh |= BH_RECEIVE;
@@ -1595,7 +1595,7 @@ static void mgsl_isr_receive_dma( struct mgsl_struct *info )
 	u16 status;
 	
 	/* clear interrupt pending and IUS bit for Rx DMA IRQ */
-	usc_OutDmaReg( info, CDIR, BIT9+BIT1 );
+	usc_OutDmaReg( info, CDIR, BIT9 | BIT1 );
 
 	/* Read the receive DMA status to identify interrupt type. */
 	/* This also clears the status bits. */
@@ -1639,7 +1639,7 @@ static void mgsl_isr_transmit_dma( struct mgsl_struct *info )
 	u16 status;
 
 	/* clear interrupt pending and IUS bit for Tx DMA IRQ */
-	usc_OutDmaReg(info, CDIR, BIT8+BIT0 );
+	usc_OutDmaReg(info, CDIR, BIT8 | BIT0 );
 
 	/* Read the transmit DMA status to identify interrupt type. */
 	/* This also clears the status bits. */
@@ -1832,8 +1832,8 @@ static void shutdown(struct mgsl_struct * info)
 	usc_DisableMasterIrqBit(info);
 	usc_stop_receiver(info);
 	usc_stop_transmitter(info);
-	usc_DisableInterrupts(info,RECEIVE_DATA + RECEIVE_STATUS +
-		TRANSMIT_DATA + TRANSMIT_STATUS + IO_PIN + MISC );
+	usc_DisableInterrupts(info,RECEIVE_DATA | RECEIVE_STATUS |
+		TRANSMIT_DATA | TRANSMIT_STATUS | IO_PIN | MISC );
 	usc_DisableDmaInterrupts(info,DICR_MASTER + DICR_TRANSMIT + DICR_RECEIVE);
 
 	/* Disable DMAEN (Port 7, Bit 14) */
@@ -1886,7 +1886,7 @@ static void mgsl_program_hw(struct mgsl_struct *info)
 	info->ri_chkcount = 0;
 	info->dsr_chkcount = 0;
 
-	usc_EnableStatusIrqs(info,SICR_CTS+SICR_DSR+SICR_DCD+SICR_RI);		
+	usc_EnableStatusIrqs(info,SICR_CTS+SICR_DSR+SICR_DCD+SICR_RI);
 	usc_EnableInterrupts(info, IO_PIN);
 	usc_get_serial_signals(info);
 		
@@ -2773,7 +2773,7 @@ static int mgsl_wait_event(struct mgsl_struct * info, int __user * mask_ptr)
 		if (!waitqueue_active(&info->event_wait_q)) {
 			/* disable enable exit hunt mode/idle rcvd IRQs */
 			usc_OutReg(info, RICR, usc_InReg(info,RICR) &
-				~(RXSTATUS_EXITED_HUNT + RXSTATUS_IDLE_RECEIVED));
+				~(RXSTATUS_EXITED_HUNT | RXSTATUS_IDLE_RECEIVED));
 		}
 		spin_unlock_irqrestore(&info->irq_spinlock,flags);
 	}
@@ -3092,7 +3092,7 @@ static void mgsl_close(struct tty_struct *tty, struct file * filp)
 		printk("%s(%d):mgsl_close(%s) entry, count=%d\n",
 			 __FILE__,__LINE__, info->device_name, info->port.count);
 
-	if (tty_port_close_start(&info->port, tty, filp) == 0)			 
+	if (tty_port_close_start(&info->port, tty, filp) == 0)
 		goto cleanup;
 
 	mutex_lock(&info->port.mutex);
@@ -4297,7 +4297,7 @@ static struct mgsl_struct* mgsl_allocate_device(void)
 		spin_lock_init(&info->irq_spinlock);
 		spin_lock_init(&info->netlock);
 		memcpy(&info->params,&default_params,sizeof(MGSL_PARAMS));
-		info->idle_mode = HDLC_TXIDLE_FLAGS;		
+		info->idle_mode = HDLC_TXIDLE_FLAGS;
 		info->num_tx_dma_buffers = 1;
 		info->num_tx_holding_buffers = 0;
 	}
@@ -4722,7 +4722,7 @@ static void usc_set_sdlc_mode( struct mgsl_struct *info )
 		else if ( info->params.flags & HDLC_FLAG_UNDERRUN_FLAG )
 			RegValue |= BIT15;
 		else if ( info->params.flags & HDLC_FLAG_UNDERRUN_CRC )
-			RegValue |= BIT15 + BIT14;
+			RegValue |= BIT15 | BIT14;
 		}
 
 		if ( info->params.preamble != HDLC_PREAMBLE_PATTERN_NONE )
@@ -4763,11 +4763,11 @@ static void usc_set_sdlc_mode( struct mgsl_struct *info )
 	switch ( info->params.encoding ) {
 	case HDLC_ENCODING_NRZB:               RegValue |= BIT13; break;
 	case HDLC_ENCODING_NRZI_MARK:          RegValue |= BIT14; break;
-	case HDLC_ENCODING_NRZI_SPACE:	       RegValue |= BIT14 + BIT13; break;
+	case HDLC_ENCODING_NRZI_SPACE:	       RegValue |= BIT14 | BIT13; break;
 	case HDLC_ENCODING_BIPHASE_MARK:       RegValue |= BIT15; break;
-	case HDLC_ENCODING_BIPHASE_SPACE:      RegValue |= BIT15 + BIT13; break;
-	case HDLC_ENCODING_BIPHASE_LEVEL:      RegValue |= BIT15 + BIT14; break;
-	case HDLC_ENCODING_DIFF_BIPHASE_LEVEL: RegValue |= BIT15 + BIT14 + BIT13; break;
+	case HDLC_ENCODING_BIPHASE_SPACE:      RegValue |= BIT15 | BIT13; break;
+	case HDLC_ENCODING_BIPHASE_LEVEL:      RegValue |= BIT15 | BIT14; break;
+	case HDLC_ENCODING_DIFF_BIPHASE_LEVEL: RegValue |= BIT15 | BIT14 | BIT13; break;
 	}
 
 	if ( (info->params.crc_type & HDLC_CRC_MASK) == HDLC_CRC_16_CCITT )
@@ -4838,15 +4838,15 @@ static void usc_set_sdlc_mode( struct mgsl_struct *info )
 	switch ( info->params.encoding ) {
 	case HDLC_ENCODING_NRZB:               RegValue |= BIT13; break;
 	case HDLC_ENCODING_NRZI_MARK:          RegValue |= BIT14; break;
-	case HDLC_ENCODING_NRZI_SPACE:         RegValue |= BIT14 + BIT13; break;
+	case HDLC_ENCODING_NRZI_SPACE:         RegValue |= BIT14 | BIT13; break;
 	case HDLC_ENCODING_BIPHASE_MARK:       RegValue |= BIT15; break;
-	case HDLC_ENCODING_BIPHASE_SPACE:      RegValue |= BIT15 + BIT13; break;
-	case HDLC_ENCODING_BIPHASE_LEVEL:      RegValue |= BIT15 + BIT14; break;
-	case HDLC_ENCODING_DIFF_BIPHASE_LEVEL: RegValue |= BIT15 + BIT14 + BIT13; break;
+	case HDLC_ENCODING_BIPHASE_SPACE:      RegValue |= BIT15 | BIT13; break;
+	case HDLC_ENCODING_BIPHASE_LEVEL:      RegValue |= BIT15 | BIT14; break;
+	case HDLC_ENCODING_DIFF_BIPHASE_LEVEL: RegValue |= BIT15 | BIT14 | BIT13; break;
 	}
 
 	if ( (info->params.crc_type & HDLC_CRC_MASK) == HDLC_CRC_16_CCITT )
-		RegValue |= BIT9 + BIT8;
+		RegValue |= BIT9 | BIT8;
 	else if ( (info->params.crc_type & HDLC_CRC_MASK) == HDLC_CRC_32_CCITT )
 		RegValue |= ( BIT12 | BIT10 | BIT9 | BIT8);
 
@@ -4957,7 +4957,7 @@ static void usc_set_sdlc_mode( struct mgsl_struct *info )
 
 	RegValue = 0x0000;
 
-	if ( info->params.flags & (HDLC_FLAG_RXC_DPLL + HDLC_FLAG_TXC_DPLL) ) {
+	if ( info->params.flags & (HDLC_FLAG_RXC_DPLL | HDLC_FLAG_TXC_DPLL) ) {
 		u32 XtalSpeed;
 		u32 DpllDivisor;
 		u16 Tc;
@@ -5019,7 +5019,7 @@ static void usc_set_sdlc_mode( struct mgsl_struct *info )
 		case HDLC_ENCODING_BIPHASE_MARK:
 		case HDLC_ENCODING_BIPHASE_SPACE: RegValue |= BIT9; break;
 		case HDLC_ENCODING_BIPHASE_LEVEL:
-		case HDLC_ENCODING_DIFF_BIPHASE_LEVEL: RegValue |= BIT9 + BIT8; break;
+		case HDLC_ENCODING_DIFF_BIPHASE_LEVEL: RegValue |= BIT9 | BIT8; break;
 		}
 	}
 
@@ -5056,8 +5056,8 @@ static void usc_set_sdlc_mode( struct mgsl_struct *info )
 	/* enable Master Interrupt Enable bit (MIE) */
 	usc_EnableMasterIrqBit( info );
 
-	usc_ClearIrqPendingBits( info, RECEIVE_STATUS + RECEIVE_DATA +
-				TRANSMIT_STATUS + TRANSMIT_DATA + MISC);
+	usc_ClearIrqPendingBits( info, RECEIVE_STATUS | RECEIVE_DATA |
+				TRANSMIT_STATUS | TRANSMIT_DATA | MISC);
 
 	/* arm RCC underflow interrupt */
 	usc_OutReg(info, SICR, (u16)(usc_InReg(info,SICR) | BIT3));
@@ -5175,14 +5175,14 @@ static void usc_set_sdlc_mode( struct mgsl_struct *info )
 	switch ( info->params.preamble_length ) {
 	case HDLC_PREAMBLE_LENGTH_16BITS: RegValue |= BIT10; break;
 	case HDLC_PREAMBLE_LENGTH_32BITS: RegValue |= BIT11; break;
-	case HDLC_PREAMBLE_LENGTH_64BITS: RegValue |= BIT11 + BIT10; break;
+	case HDLC_PREAMBLE_LENGTH_64BITS: RegValue |= BIT11 | BIT10; break;
 	}
 
 	switch ( info->params.preamble ) {
-	case HDLC_PREAMBLE_PATTERN_FLAGS: RegValue |= BIT8 + BIT12; break;
+	case HDLC_PREAMBLE_PATTERN_FLAGS: RegValue |= BIT8 | BIT12; break;
 	case HDLC_PREAMBLE_PATTERN_ONES:  RegValue |= BIT8; break;
 	case HDLC_PREAMBLE_PATTERN_10:    RegValue |= BIT9; break;
-	case HDLC_PREAMBLE_PATTERN_01:    RegValue |= BIT9 + BIT8; break;
+	case HDLC_PREAMBLE_PATTERN_01:    RegValue |= BIT9 | BIT8; break;
 	}
 
 	usc_OutReg( info, CCR, RegValue );
@@ -5221,7 +5221,7 @@ static void usc_enable_loopback(struct mgsl_struct *info, int enable)
 {
 	if (enable) {
 		/* blank external TXD output */
-		usc_OutReg(info,IOCR,usc_InReg(info,IOCR) | (BIT7+BIT6));
+		usc_OutReg(info,IOCR,usc_InReg(info,IOCR) | (BIT7 | BIT6));
 	
 		/* Clock mode Control Register (CMCR)
 		 *
@@ -5260,7 +5260,7 @@ static void usc_enable_loopback(struct mgsl_struct *info, int enable)
 		outw( 0x0300, info->io_base + CCAR );
 	} else {
 		/* enable external TXD output */
-		usc_OutReg(info,IOCR,usc_InReg(info,IOCR) & ~(BIT7+BIT6));
+		usc_OutReg(info,IOCR,usc_InReg(info,IOCR) & ~(BIT7 | BIT6));
 	
 		/* clear Internal Data loopback mode */
 		info->loopback_bits = 0;
@@ -5447,13 +5447,13 @@ static void usc_process_rxoverrun_sync( struct mgsl_struct *info )
 		usc_OutDmaReg( info, NRARU, (u16)(phys_addr >> 16) );
 
 		usc_UnlatchRxstatusBits( info, RXSTATUS_ALL );
-		usc_ClearIrqPendingBits( info, RECEIVE_DATA + RECEIVE_STATUS );
+		usc_ClearIrqPendingBits( info, RECEIVE_DATA | RECEIVE_STATUS );
 		usc_EnableInterrupts( info, RECEIVE_STATUS );
 
 		/* 1. Arm End of Buffer (EOB) Receive DMA Interrupt (BIT2 of RDIAR) */
 		/* 2. Enable Receive DMA Interrupts (BIT1 of DICR) */
 
-		usc_OutDmaReg( info, RDIAR, BIT3 + BIT2 );
+		usc_OutDmaReg( info, RDIAR, BIT3 | BIT2 );
 		usc_OutDmaReg( info, DICR, (u16)(usc_InDmaReg(info,DICR) | BIT1) );
 		usc_DmaCmd( info, DmaCmd_InitRxChannel );
 		if ( info->params.flags & HDLC_FLAG_AUTO_DCD )
@@ -5488,8 +5488,8 @@ static void usc_stop_receiver( struct mgsl_struct *info )
 	usc_DmaCmd( info, DmaCmd_ResetRxChannel );
 
 	usc_UnlatchRxstatusBits( info, RXSTATUS_ALL );
-	usc_ClearIrqPendingBits( info, RECEIVE_DATA + RECEIVE_STATUS );
-	usc_DisableInterrupts( info, RECEIVE_DATA + RECEIVE_STATUS );
+	usc_ClearIrqPendingBits( info, RECEIVE_DATA | RECEIVE_STATUS );
+	usc_DisableInterrupts( info, RECEIVE_DATA | RECEIVE_STATUS );
 
 	usc_EnableReceiver(info,DISABLE_UNCONDITIONAL);
 
@@ -5536,13 +5536,13 @@ static void usc_start_receiver( struct mgsl_struct *info )
 		usc_OutDmaReg( info, NRARU, (u16)(phys_addr >> 16) );
 
 		usc_UnlatchRxstatusBits( info, RXSTATUS_ALL );
-		usc_ClearIrqPendingBits( info, RECEIVE_DATA + RECEIVE_STATUS );
+		usc_ClearIrqPendingBits( info, RECEIVE_DATA | RECEIVE_STATUS );
 		usc_EnableInterrupts( info, RECEIVE_STATUS );
 
 		/* 1. Arm End of Buffer (EOB) Receive DMA Interrupt (BIT2 of RDIAR) */
 		/* 2. Enable Receive DMA Interrupts (BIT1 of DICR) */
 
-		usc_OutDmaReg( info, RDIAR, BIT3 + BIT2 );
+		usc_OutDmaReg( info, RDIAR, BIT3 | BIT2 );
 		usc_OutDmaReg( info, DICR, (u16)(usc_InDmaReg(info,DICR) | BIT1) );
 		usc_DmaCmd( info, DmaCmd_InitRxChannel );
 		if ( info->params.flags & HDLC_FLAG_AUTO_DCD )
@@ -5551,7 +5551,7 @@ static void usc_start_receiver( struct mgsl_struct *info )
 			usc_EnableReceiver(info,ENABLE_UNCONDITIONAL);
 	} else {
 		usc_UnlatchRxstatusBits(info, RXSTATUS_ALL);
-		usc_ClearIrqPendingBits(info, RECEIVE_DATA + RECEIVE_STATUS);
+		usc_ClearIrqPendingBits(info, RECEIVE_DATA | RECEIVE_STATUS);
 		usc_EnableInterrupts(info, RECEIVE_DATA);
 
 		usc_RTCmd( info, RTCmd_PurgeRxFifo );
@@ -5925,7 +5925,7 @@ static void usc_set_async_mode( struct mgsl_struct *info )
 	RegValue = 0;
 
 	if ( info->params.data_bits != 8 )
-		RegValue |= BIT4+BIT3+BIT2;
+		RegValue |= BIT4 | BIT3 | BIT2;
 
 	if ( info->params.parity != ASYNC_PARITY_NONE ) {
 		RegValue |= BIT5;
@@ -5982,7 +5982,7 @@ static void usc_set_async_mode( struct mgsl_struct *info )
 	RegValue = 0;
 
 	if ( info->params.data_bits != 8 )
-		RegValue |= BIT4+BIT3+BIT2;
+		RegValue |= BIT4 | BIT3 | BIT2;
 
 	if ( info->params.parity != ASYNC_PARITY_NONE ) {
 		RegValue |= BIT5;
@@ -6129,7 +6129,7 @@ static void usc_loopback_frame( struct mgsl_struct *info )
 							
 	/* WAIT FOR RECEIVE COMPLETE */
 	for (i=0 ; i<1000 ; i++)
-		if (usc_InReg( info, RCSR ) & (BIT8 + BIT4 + BIT3 + BIT1))
+		if (usc_InReg( info, RCSR ) & (BIT8 | BIT4 | BIT3 | BIT1))
 			break;
 
 	/* clear Internal Data loopback mode */
@@ -6579,8 +6579,8 @@ static bool mgsl_get_rx_frame(struct mgsl_struct *info)
 	
 	status = info->rx_buffer_list[EndIndex].status;
 
-	if ( status & (RXSTATUS_SHORT_FRAME + RXSTATUS_OVERRUN +
-			RXSTATUS_CRC_ERROR + RXSTATUS_ABORT) ) {
+	if ( status & (RXSTATUS_SHORT_FRAME | RXSTATUS_OVERRUN |
+			RXSTATUS_CRC_ERROR | RXSTATUS_ABORT) ) {
 		if ( status & RXSTATUS_SHORT_FRAME )
 			info->icount.rxshort++;
 		else if ( status & RXSTATUS_ABORT )
@@ -6762,8 +6762,8 @@ static bool mgsl_get_raw_rx_frame(struct mgsl_struct *info)
 
 		status = info->rx_buffer_list[CurrentIndex].status;
 
-		if ( status & (RXSTATUS_SHORT_FRAME + RXSTATUS_OVERRUN +
-				RXSTATUS_CRC_ERROR + RXSTATUS_ABORT) ) {
+		if ( status & (RXSTATUS_SHORT_FRAME | RXSTATUS_OVERRUN |
+				RXSTATUS_CRC_ERROR | RXSTATUS_ABORT) ) {
 			if ( status & RXSTATUS_SHORT_FRAME )
 				info->icount.rxshort++;
 			else if ( status & RXSTATUS_ABORT )
@@ -6899,7 +6899,7 @@ static void mgsl_load_tx_dma_buffer(struct mgsl_struct *info,
 		/* set CMR:13 to start transmit when
 		 * next GoAhead (abort) is received
 		 */
-	 	info->cmr_value |= BIT13;			  
+	 	info->cmr_value |= BIT13;
 	}
 		
 	/* begin loading the frame in the next available tx dma
@@ -7278,7 +7278,7 @@ static bool mgsl_dma_test( struct mgsl_struct *info )
 		
 		spin_unlock_irqrestore(&info->irq_spinlock,flags);
 
-						
+
 		/******************************/
 		/* WAIT FOR TRANSMIT COMPLETE */
 		/******************************/
@@ -7292,7 +7292,7 @@ static bool mgsl_dma_test( struct mgsl_struct *info )
 		status = usc_InReg( info, TCSR );
 		spin_unlock_irqrestore(&info->irq_spinlock,flags);
 
-		while ( !(status & (BIT6+BIT5+BIT4+BIT2+BIT1)) ) {
+		while ( !(status & (BIT6 | BIT5 | BIT4 | BIT2 | BIT1)) ) {
 			if (time_after(jiffies, EndTime)) {
 				rc = false;
 				break;
@@ -7307,7 +7307,7 @@ static bool mgsl_dma_test( struct mgsl_struct *info )
 
 	if ( rc ){
 		/* CHECK FOR TRANSMIT ERRORS */
-		if ( status & (BIT5 + BIT1) ) 
+		if ( status & (BIT5 | BIT1) )
 			rc = false;
 	}
 
@@ -7333,7 +7333,7 @@ static bool mgsl_dma_test( struct mgsl_struct *info )
 		/* CHECK FOR RECEIVE ERRORS */
 		status = info->rx_buffer_list[0].status;
 
-		if ( status & (BIT8 + BIT3 + BIT1) ) {
+		if ( status & (BIT8 | BIT3 | BIT1) ) {
 			/* receive error has occurred */
 			rc = false;
 		} else {
@@ -7605,7 +7605,7 @@ static void usc_loopmode_send_done( struct mgsl_struct * info )
 {
  	info->loopmode_send_done_requested = false;
  	/* clear CMR:13 to 0 to start echoing RxData to TxData */
- 	info->cmr_value &= ~BIT13;			  
+ 	info->cmr_value &= ~BIT13;
  	usc_OutReg(info, CMR, info->cmr_value);
 }
 
diff --git a/drivers/tty/tty_buffer.c b/drivers/tty/tty_buffer.c
index 9121c1f7aee..c043136fbe5 100644
--- a/drivers/tty/tty_buffer.c
+++ b/drivers/tty/tty_buffer.c
@@ -18,31 +18,118 @@
 #include <linux/module.h>
 #include <linux/ratelimit.h>
 
+
+#define MIN_TTYB_SIZE	256
+#define TTYB_ALIGN_MASK	255
+
+/*
+ * Byte threshold to limit memory consumption for flip buffers.
+ * The actual memory limit is > 2x this amount.
+ */
+#define TTYB_MEM_LIMIT	65536
+
+/*
+ * We default to dicing tty buffer allocations to this many characters
+ * in order to avoid multiple page allocations. We know the size of
+ * tty_buffer itself but it must also be taken into account that the
+ * the buffer is 256 byte aligned. See tty_buffer_find for the allocation
+ * logic this must match
+ */
+
+#define TTY_BUFFER_PAGE	(((PAGE_SIZE - sizeof(struct tty_buffer)) / 2) & ~0xFF)
+
+
+/**
+ *	tty_buffer_lock_exclusive	-	gain exclusive access to buffer
+ *	tty_buffer_unlock_exclusive	-	release exclusive access
+ *
+ *	@port - tty_port owning the flip buffer
+ *
+ *	Guarantees safe use of the line discipline's receive_buf() method by
+ *	excluding the buffer work and any pending flush from using the flip
+ *	buffer. Data can continue to be added concurrently to the flip buffer
+ *	from the driver side.
+ *
+ *	On release, the buffer work is restarted if there is data in the
+ *	flip buffer
+ */
+
+void tty_buffer_lock_exclusive(struct tty_port *port)
+{
+	struct tty_bufhead *buf = &port->buf;
+
+	atomic_inc(&buf->priority);
+	mutex_lock(&buf->lock);
+}
+
+void tty_buffer_unlock_exclusive(struct tty_port *port)
+{
+	struct tty_bufhead *buf = &port->buf;
+	int restart;
+
+	restart = buf->head->commit != buf->head->read;
+
+	atomic_dec(&buf->priority);
+	mutex_unlock(&buf->lock);
+	if (restart)
+		queue_work(system_unbound_wq, &buf->work);
+}
+
+/**
+ *	tty_buffer_space_avail	-	return unused buffer space
+ *	@port - tty_port owning the flip buffer
+ *
+ *	Returns the # of bytes which can be written by the driver without
+ *	reaching the buffer limit.
+ *
+ *	Note: this does not guarantee that memory is available to write
+ *	the returned # of bytes (use tty_prepare_flip_string_xxx() to
+ *	pre-allocate if memory guarantee is required).
+ */
+
+int tty_buffer_space_avail(struct tty_port *port)
+{
+	int space = TTYB_MEM_LIMIT - atomic_read(&port->buf.memory_used);
+	return max(space, 0);
+}
+
+static void tty_buffer_reset(struct tty_buffer *p, size_t size)
+{
+	p->used = 0;
+	p->size = size;
+	p->next = NULL;
+	p->commit = 0;
+	p->read = 0;
+}
+
 /**
  *	tty_buffer_free_all		-	free buffers used by a tty
  *	@tty: tty to free from
  *
  *	Remove all the buffers pending on a tty whether queued with data
  *	or in the free ring. Must be called when the tty is no longer in use
- *
- *	Locking: none
  */
 
 void tty_buffer_free_all(struct tty_port *port)
 {
 	struct tty_bufhead *buf = &port->buf;
-	struct tty_buffer *thead;
+	struct tty_buffer *p, *next;
+	struct llist_node *llist;
 
-	while ((thead = buf->head) != NULL) {
-		buf->head = thead->next;
-		kfree(thead);
-	}
-	while ((thead = buf->free) != NULL) {
-		buf->free = thead->next;
-		kfree(thead);
+	while ((p = buf->head) != NULL) {
+		buf->head = p->next;
+		if (p->size > 0)
+			kfree(p);
 	}
-	buf->tail = NULL;
-	buf->memory_used = 0;
+	llist = llist_del_all(&buf->free);
+	llist_for_each_entry_safe(p, next, llist, free)
+		kfree(p);
+
+	tty_buffer_reset(&buf->sentinel, 0);
+	buf->head = &buf->sentinel;
+	buf->tail = &buf->sentinel;
+
+	atomic_set(&buf->memory_used, 0);
 }
 
 /**
@@ -51,29 +138,39 @@ void tty_buffer_free_all(struct tty_port *port)
  *	@size: desired size (characters)
  *
  *	Allocate a new tty buffer to hold the desired number of characters.
+ *	We round our buffers off in 256 character chunks to get better
+ *	allocation behaviour.
  *	Return NULL if out of memory or the allocation would exceed the
  *	per device queue
- *
- *	Locking: Caller must hold tty->buf.lock
  */
 
 static struct tty_buffer *tty_buffer_alloc(struct tty_port *port, size_t size)
 {
+	struct llist_node *free;
 	struct tty_buffer *p;
 
-	if (port->buf.memory_used + size > 65536)
+	/* Round the buffer size out */
+	size = __ALIGN_MASK(size, TTYB_ALIGN_MASK);
+
+	if (size <= MIN_TTYB_SIZE) {
+		free = llist_del_first(&port->buf.free);
+		if (free) {
+			p = llist_entry(free, struct tty_buffer, free);
+			goto found;
+		}
+	}
+
+	/* Should possibly check if this fails for the largest buffer we
+	   have queued and recycle that ? */
+	if (atomic_read(&port->buf.memory_used) > TTYB_MEM_LIMIT)
 		return NULL;
 	p = kmalloc(sizeof(struct tty_buffer) + 2 * size, GFP_ATOMIC);
 	if (p == NULL)
 		return NULL;
-	p->used = 0;
-	p->size = size;
-	p->next = NULL;
-	p->commit = 0;
-	p->read = 0;
-	p->char_buf_ptr = (char *)(p->data);
-	p->flag_buf_ptr = (unsigned char *)p->char_buf_ptr + size;
-	port->buf.memory_used += size;
+
+found:
+	tty_buffer_reset(p, size);
+	atomic_add(size, &port->buf.memory_used);
 	return p;
 }
 
@@ -84,8 +181,6 @@ static struct tty_buffer *tty_buffer_alloc(struct tty_port *port, size_t size)
  *
  *	Free a tty buffer, or add it to the free list according to our
  *	internal strategy
- *
- *	Locking: Caller must hold tty->buf.lock
  */
 
 static void tty_buffer_free(struct tty_port *port, struct tty_buffer *b)
@@ -93,41 +188,12 @@ static void tty_buffer_free(struct tty_port *port, struct tty_buffer *b)
 	struct tty_bufhead *buf = &port->buf;
 
 	/* Dumb strategy for now - should keep some stats */
-	buf->memory_used -= b->size;
-	WARN_ON(buf->memory_used < 0);
+	WARN_ON(atomic_sub_return(b->size, &buf->memory_used) < 0);
 
-	if (b->size >= 512)
+	if (b->size > MIN_TTYB_SIZE)
 		kfree(b);
-	else {
-		b->next = buf->free;
-		buf->free = b;
-	}
-}
-
-/**
- *	__tty_buffer_flush		-	flush full tty buffers
- *	@tty: tty to flush
- *
- *	flush all the buffers containing receive data. Caller must
- *	hold the buffer lock and must have ensured no parallel flush to
- *	ldisc is running.
- *
- *	Locking: Caller must hold tty->buf.lock
- */
-
-static void __tty_buffer_flush(struct tty_port *port)
-{
-	struct tty_bufhead *buf = &port->buf;
-	struct tty_buffer *thead;
-
-	if (unlikely(buf->head == NULL))
-		return;
-	while ((thead = buf->head->next) != NULL) {
-		tty_buffer_free(port, buf->head);
-		buf->head = thead;
-	}
-	WARN_ON(buf->head != buf->tail);
-	buf->head->read = buf->head->commit;
+	else if (b->size > 0)
+		llist_add(&b->free, &buf->free);
 }
 
 /**
@@ -138,65 +204,28 @@ static void __tty_buffer_flush(struct tty_port *port)
  *	being processed by flush_to_ldisc then we defer the processing
  *	to that function
  *
- *	Locking: none
+ *	Locking: takes buffer lock to ensure single-threaded flip buffer
+ *		 'consumer'
  */
 
 void tty_buffer_flush(struct tty_struct *tty)
 {
 	struct tty_port *port = tty->port;
 	struct tty_bufhead *buf = &port->buf;
-	unsigned long flags;
-
-	spin_lock_irqsave(&buf->lock, flags);
-
-	/* If the data is being pushed to the tty layer then we can't
-	   process it here. Instead set a flag and the flush_to_ldisc
-	   path will process the flush request before it exits */
-	if (test_bit(TTYP_FLUSHING, &port->iflags)) {
-		set_bit(TTYP_FLUSHPENDING, &port->iflags);
-		spin_unlock_irqrestore(&buf->lock, flags);
-		wait_event(tty->read_wait,
-				test_bit(TTYP_FLUSHPENDING, &port->iflags) == 0);
-		return;
-	} else
-		__tty_buffer_flush(port);
-	spin_unlock_irqrestore(&buf->lock, flags);
-}
+	struct tty_buffer *next;
 
-/**
- *	tty_buffer_find		-	find a free tty buffer
- *	@tty: tty owning the buffer
- *	@size: characters wanted
- *
- *	Locate an existing suitable tty buffer or if we are lacking one then
- *	allocate a new one. We round our buffers off in 256 character chunks
- *	to get better allocation behaviour.
- *
- *	Locking: Caller must hold tty->buf.lock
- */
+	atomic_inc(&buf->priority);
 
-static struct tty_buffer *tty_buffer_find(struct tty_port *port, size_t size)
-{
-	struct tty_buffer **tbh = &port->buf.free;
-	while ((*tbh) != NULL) {
-		struct tty_buffer *t = *tbh;
-		if (t->size >= size) {
-			*tbh = t->next;
-			t->next = NULL;
-			t->used = 0;
-			t->commit = 0;
-			t->read = 0;
-			port->buf.memory_used += t->size;
-			return t;
-		}
-		tbh = &((*tbh)->next);
+	mutex_lock(&buf->lock);
+	while ((next = buf->head->next) != NULL) {
+		tty_buffer_free(port, buf->head);
+		buf->head = next;
 	}
-	/* Round the buffer size out */
-	size = (size + 0xFF) & ~0xFF;
-	return tty_buffer_alloc(port, size);
-	/* Should possibly check if this fails for the largest buffer we
-	   have queued and recycle that ? */
+	buf->head->read = buf->head->commit;
+	atomic_dec(&buf->priority);
+	mutex_unlock(&buf->lock);
 }
+
 /**
  *	tty_buffer_request_room		-	grow tty buffer if needed
  *	@tty: tty structure
@@ -204,38 +233,26 @@ static struct tty_buffer *tty_buffer_find(struct tty_port *port, size_t size)
  *
  *	Make at least size bytes of linear space available for the tty
  *	buffer. If we fail return the size we managed to find.
- *
- *	Locking: Takes port->buf.lock
  */
 int tty_buffer_request_room(struct tty_port *port, size_t size)
 {
 	struct tty_bufhead *buf = &port->buf;
 	struct tty_buffer *b, *n;
 	int left;
-	unsigned long flags;
-	spin_lock_irqsave(&buf->lock, flags);
-	/* OPTIMISATION: We could keep a per tty "zero" sized buffer to
-	   remove this conditional if its worth it. This would be invisible
-	   to the callers */
+
 	b = buf->tail;
-	if (b != NULL)
-		left = b->size - b->used;
-	else
-		left = 0;
+	left = b->size - b->used;
 
 	if (left < size) {
 		/* This is the slow path - looking for new buffers to use */
-		if ((n = tty_buffer_find(port, size)) != NULL) {
-			if (b != NULL) {
-				b->next = n;
-				b->commit = b->used;
-			} else
-				buf->head = n;
+		if ((n = tty_buffer_alloc(port, size)) != NULL) {
 			buf->tail = n;
+			b->commit = b->used;
+			smp_mb();
+			b->next = n;
 		} else
 			size = left;
 	}
-	spin_unlock_irqrestore(&buf->lock, flags);
 	return size;
 }
 EXPORT_SYMBOL_GPL(tty_buffer_request_room);
@@ -249,8 +266,6 @@ EXPORT_SYMBOL_GPL(tty_buffer_request_room);
  *
  *	Queue a series of bytes to the tty buffering. All the characters
  *	passed are marked with the supplied flag. Returns the number added.
- *
- *	Locking: Called functions may take port->buf.lock
  */
 
 int tty_insert_flip_string_fixed_flag(struct tty_port *port,
@@ -261,12 +276,10 @@ int tty_insert_flip_string_fixed_flag(struct tty_port *port,
 		int goal = min_t(size_t, size - copied, TTY_BUFFER_PAGE);
 		int space = tty_buffer_request_room(port, goal);
 		struct tty_buffer *tb = port->buf.tail;
-		/* If there is no space then tb may be NULL */
-		if (unlikely(space == 0)) {
+		if (unlikely(space == 0))
 			break;
-		}
-		memcpy(tb->char_buf_ptr + tb->used, chars, space);
-		memset(tb->flag_buf_ptr + tb->used, flag, space);
+		memcpy(char_buf_ptr(tb, tb->used), chars, space);
+		memset(flag_buf_ptr(tb, tb->used), flag, space);
 		tb->used += space;
 		copied += space;
 		chars += space;
@@ -287,8 +300,6 @@ EXPORT_SYMBOL(tty_insert_flip_string_fixed_flag);
  *	Queue a series of bytes to the tty buffering. For each character
  *	the flags array indicates the status of the character. Returns the
  *	number added.
- *
- *	Locking: Called functions may take port->buf.lock
  */
 
 int tty_insert_flip_string_flags(struct tty_port *port,
@@ -299,12 +310,10 @@ int tty_insert_flip_string_flags(struct tty_port *port,
 		int goal = min_t(size_t, size - copied, TTY_BUFFER_PAGE);
 		int space = tty_buffer_request_room(port, goal);
 		struct tty_buffer *tb = port->buf.tail;
-		/* If there is no space then tb may be NULL */
-		if (unlikely(space == 0)) {
+		if (unlikely(space == 0))
 			break;
-		}
-		memcpy(tb->char_buf_ptr + tb->used, chars, space);
-		memcpy(tb->flag_buf_ptr + tb->used, flags, space);
+		memcpy(char_buf_ptr(tb, tb->used), chars, space);
+		memcpy(flag_buf_ptr(tb, tb->used), flags, space);
 		tb->used += space;
 		copied += space;
 		chars += space;
@@ -325,20 +334,14 @@ EXPORT_SYMBOL(tty_insert_flip_string_flags);
  *	processing by the line discipline.
  *	Note that this function can only be used when the low_latency flag
  *	is unset. Otherwise the workqueue won't be flushed.
- *
- *	Locking: Takes port->buf.lock
  */
 
 void tty_schedule_flip(struct tty_port *port)
 {
 	struct tty_bufhead *buf = &port->buf;
-	unsigned long flags;
 	WARN_ON(port->low_latency);
 
-	spin_lock_irqsave(&buf->lock, flags);
-	if (buf->tail != NULL)
-		buf->tail->commit = buf->tail->used;
-	spin_unlock_irqrestore(&buf->lock, flags);
+	buf->tail->commit = buf->tail->used;
 	schedule_work(&buf->work);
 }
 EXPORT_SYMBOL(tty_schedule_flip);
@@ -354,8 +357,6 @@ EXPORT_SYMBOL(tty_schedule_flip);
  *	accounted for as ready for normal characters. This is used for drivers
  *	that need their own block copy routines into the buffer. There is no
  *	guarantee the buffer is a DMA target!
- *
- *	Locking: May call functions taking port->buf.lock
  */
 
 int tty_prepare_flip_string(struct tty_port *port, unsigned char **chars,
@@ -364,8 +365,8 @@ int tty_prepare_flip_string(struct tty_port *port, unsigned char **chars,
 	int space = tty_buffer_request_room(port, size);
 	if (likely(space)) {
 		struct tty_buffer *tb = port->buf.tail;
-		*chars = tb->char_buf_ptr + tb->used;
-		memset(tb->flag_buf_ptr + tb->used, TTY_NORMAL, space);
+		*chars = char_buf_ptr(tb, tb->used);
+		memset(flag_buf_ptr(tb, tb->used), TTY_NORMAL, space);
 		tb->used += space;
 	}
 	return space;
@@ -384,8 +385,6 @@ EXPORT_SYMBOL_GPL(tty_prepare_flip_string);
  *	accounted for as ready for characters. This is used for drivers
  *	that need their own block copy routines into the buffer. There is no
  *	guarantee the buffer is a DMA target!
- *
- *	Locking: May call functions taking port->buf.lock
  */
 
 int tty_prepare_flip_string_flags(struct tty_port *port,
@@ -394,8 +393,8 @@ int tty_prepare_flip_string_flags(struct tty_port *port,
 	int space = tty_buffer_request_room(port, size);
 	if (likely(space)) {
 		struct tty_buffer *tb = port->buf.tail;
-		*chars = tb->char_buf_ptr + tb->used;
-		*flags = tb->flag_buf_ptr + tb->used;
+		*chars = char_buf_ptr(tb, tb->used);
+		*flags = flag_buf_ptr(tb, tb->used);
 		tb->used += space;
 	}
 	return space;
@@ -403,6 +402,23 @@ int tty_prepare_flip_string_flags(struct tty_port *port,
 EXPORT_SYMBOL_GPL(tty_prepare_flip_string_flags);
 
 
+static int
+receive_buf(struct tty_struct *tty, struct tty_buffer *head, int count)
+{
+	struct tty_ldisc *disc = tty->ldisc;
+	unsigned char *p = char_buf_ptr(head, head->read);
+	char	      *f = flag_buf_ptr(head, head->read);
+
+	if (disc->ops->receive_buf2)
+		count = disc->ops->receive_buf2(tty, p, f, count);
+	else {
+		count = min_t(int, count, tty->receive_room);
+		if (count)
+			disc->ops->receive_buf(tty, p, f, count);
+	}
+	head->read += count;
+	return count;
+}
 
 /**
  *	flush_to_ldisc
@@ -411,9 +427,10 @@ EXPORT_SYMBOL_GPL(tty_prepare_flip_string_flags);
  *	This routine is called out of the software interrupt to flush data
  *	from the buffer chain to the line discipline.
  *
- *	Locking: holds tty->buf.lock to guard buffer list. Drops the lock
- *	while invoking the line discipline receive_buf method. The
- *	receive_buf method is single threaded for each tty instance.
+ *	The receive_buf method is single threaded for each tty instance.
+ *
+ *	Locking: takes buffer lock to ensure single-threaded flip buffer
+ *		 'consumer'
  */
 
 static void flush_to_ldisc(struct work_struct *work)
@@ -421,7 +438,6 @@ static void flush_to_ldisc(struct work_struct *work)
 	struct tty_port *port = container_of(work, struct tty_port, buf.work);
 	struct tty_bufhead *buf = &port->buf;
 	struct tty_struct *tty;
-	unsigned long 	flags;
 	struct tty_ldisc *disc;
 
 	tty = port->itty;
@@ -429,52 +445,34 @@ static void flush_to_ldisc(struct work_struct *work)
 		return;
 
 	disc = tty_ldisc_ref(tty);
-	if (disc == NULL)	/*  !TTY_LDISC */
+	if (disc == NULL)
 		return;
 
-	spin_lock_irqsave(&buf->lock, flags);
-
-	if (!test_and_set_bit(TTYP_FLUSHING, &port->iflags)) {
-		struct tty_buffer *head;
-		while ((head = buf->head) != NULL) {
-			int count;
-			char *char_buf;
-			unsigned char *flag_buf;
-
-			count = head->commit - head->read;
-			if (!count) {
-				if (head->next == NULL)
-					break;
-				buf->head = head->next;
-				tty_buffer_free(port, head);
-				continue;
-			}
-			if (!tty->receive_room)
-				break;
-			if (count > tty->receive_room)
-				count = tty->receive_room;
-			char_buf = head->char_buf_ptr + head->read;
-			flag_buf = head->flag_buf_ptr + head->read;
-			head->read += count;
-			spin_unlock_irqrestore(&buf->lock, flags);
-			disc->ops->receive_buf(tty, char_buf,
-							flag_buf, count);
-			spin_lock_irqsave(&buf->lock, flags);
-			/* Ldisc or user is trying to flush the buffers.
-			   We may have a deferred request to flush the
-			   input buffer, if so pull the chain under the lock
-			   and empty the queue */
-			if (test_bit(TTYP_FLUSHPENDING, &port->iflags)) {
-				__tty_buffer_flush(port);
-				clear_bit(TTYP_FLUSHPENDING, &port->iflags);
-				wake_up(&tty->read_wait);
+	mutex_lock(&buf->lock);
+
+	while (1) {
+		struct tty_buffer *head = buf->head;
+		int count;
+
+		/* Ldisc or user is trying to gain exclusive access */
+		if (atomic_read(&buf->priority))
+			break;
+
+		count = head->commit - head->read;
+		if (!count) {
+			if (head->next == NULL)
 				break;
-			}
+			buf->head = head->next;
+			tty_buffer_free(port, head);
+			continue;
 		}
-		clear_bit(TTYP_FLUSHING, &port->iflags);
+
+		count = receive_buf(tty, head, count);
+		if (!count)
+			break;
 	}
 
-	spin_unlock_irqrestore(&buf->lock, flags);
+	mutex_unlock(&buf->lock);
 
 	tty_ldisc_deref(disc);
 }
@@ -503,19 +501,13 @@ void tty_flush_to_ldisc(struct tty_struct *tty)
  *
  *	In the event of the queue being busy for flipping the work will be
  *	held off and retried later.
- *
- *	Locking: tty buffer lock. Driver locks in low latency mode.
  */
 
 void tty_flip_buffer_push(struct tty_port *port)
 {
 	struct tty_bufhead *buf = &port->buf;
-	unsigned long flags;
 
-	spin_lock_irqsave(&buf->lock, flags);
-	if (buf->tail != NULL)
-		buf->tail->commit = buf->tail->used;
-	spin_unlock_irqrestore(&buf->lock, flags);
+	buf->tail->commit = buf->tail->used;
 
 	if (port->low_latency)
 		flush_to_ldisc(&buf->work);
@@ -530,19 +522,18 @@ EXPORT_SYMBOL(tty_flip_buffer_push);
  *
  *	Set up the initial state of the buffer management for a tty device.
  *	Must be called before the other tty buffer functions are used.
- *
- *	Locking: none
  */
 
 void tty_buffer_init(struct tty_port *port)
 {
 	struct tty_bufhead *buf = &port->buf;
 
-	spin_lock_init(&buf->lock);
-	buf->head = NULL;
-	buf->tail = NULL;
-	buf->free = NULL;
-	buf->memory_used = 0;
+	mutex_init(&buf->lock);
+	tty_buffer_reset(&buf->sentinel, 0);
+	buf->head = &buf->sentinel;
+	buf->tail = &buf->sentinel;
+	init_llist_head(&buf->free);
+	atomic_set(&buf->memory_used, 0);
+	atomic_set(&buf->priority, 0);
 	INIT_WORK(&buf->work, flush_to_ldisc);
 }
-
diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c
index 366af832794..a9355ce1c6d 100644
--- a/drivers/tty/tty_io.c
+++ b/drivers/tty/tty_io.c
@@ -603,8 +603,8 @@ static int tty_signal_session_leader(struct tty_struct *tty, int exit_session)
  *		BTM
  *		  redirect lock for undoing redirection
  *		  file list lock for manipulating list of ttys
- *		  tty_ldisc_lock from called functions
- *		  termios_mutex resetting termios data
+ *		  tty_ldiscs_lock from called functions
+ *		  termios_rwsem resetting termios data
  *		  tasklist_lock to walk task list for hangup event
  *		    ->siglock to protect ->signal/->sighand
  */
@@ -629,6 +629,11 @@ static void __tty_hangup(struct tty_struct *tty, int exit_session)
 
 	tty_lock(tty);
 
+	if (test_bit(TTY_HUPPED, &tty->flags)) {
+		tty_unlock(tty);
+		return;
+	}
+
 	/* some functions below drop BTM, so we need this bit */
 	set_bit(TTY_HUPPING, &tty->flags);
 
@@ -664,7 +669,6 @@ static void __tty_hangup(struct tty_struct *tty, int exit_session)
 
 	spin_lock_irq(&tty->ctrl_lock);
 	clear_bit(TTY_THROTTLED, &tty->flags);
-	clear_bit(TTY_PUSH, &tty->flags);
 	clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
 	put_pid(tty->session);
 	put_pid(tty->pgrp);
@@ -1388,8 +1392,7 @@ static int tty_reopen(struct tty_struct *tty)
 	struct tty_driver *driver = tty->driver;
 
 	if (test_bit(TTY_CLOSING, &tty->flags) ||
-			test_bit(TTY_HUPPING, &tty->flags) ||
-			test_bit(TTY_LDISC_CHANGING, &tty->flags))
+			test_bit(TTY_HUPPING, &tty->flags))
 		return -EIO;
 
 	if (driver->type == TTY_DRIVER_TYPE_PTY &&
@@ -1405,7 +1408,7 @@ static int tty_reopen(struct tty_struct *tty)
 	}
 	tty->count++;
 
-	WARN_ON(!test_bit(TTY_LDISC, &tty->flags));
+	WARN_ON(!tty->ldisc);
 
 	return 0;
 }
@@ -2202,7 +2205,7 @@ static int tty_fasync(int fd, struct file *filp, int on)
  *	FIXME: does not honour flow control ??
  *
  *	Locking:
- *		Called functions take tty_ldisc_lock
+ *		Called functions take tty_ldiscs_lock
  *		current->signal->tty check is safe without locks
  *
  *	FIXME: may race normal receive processing
@@ -2231,7 +2234,7 @@ static int tiocsti(struct tty_struct *tty, char __user *p)
  *
  *	Copies the kernel idea of the window size into the user buffer.
  *
- *	Locking: tty->termios_mutex is taken to ensure the winsize data
+ *	Locking: tty->winsize_mutex is taken to ensure the winsize data
  *		is consistent.
  */
 
@@ -2239,9 +2242,9 @@ static int tiocgwinsz(struct tty_struct *tty, struct winsize __user *arg)
 {
 	int err;
 
-	mutex_lock(&tty->termios_mutex);
+	mutex_lock(&tty->winsize_mutex);
 	err = copy_to_user(arg, &tty->winsize, sizeof(*arg));
-	mutex_unlock(&tty->termios_mutex);
+	mutex_unlock(&tty->winsize_mutex);
 
 	return err ? -EFAULT: 0;
 }
@@ -2262,7 +2265,7 @@ int tty_do_resize(struct tty_struct *tty, struct winsize *ws)
 	unsigned long flags;
 
 	/* Lock the tty */
-	mutex_lock(&tty->termios_mutex);
+	mutex_lock(&tty->winsize_mutex);
 	if (!memcmp(ws, &tty->winsize, sizeof(*ws)))
 		goto done;
 	/* Get the PID values and reference them so we can
@@ -2277,7 +2280,7 @@ int tty_do_resize(struct tty_struct *tty, struct winsize *ws)
 
 	tty->winsize = *ws;
 done:
-	mutex_unlock(&tty->termios_mutex);
+	mutex_unlock(&tty->winsize_mutex);
 	return 0;
 }
 EXPORT_SYMBOL(tty_do_resize);
@@ -3016,8 +3019,10 @@ void initialize_tty_struct(struct tty_struct *tty,
 	tty->session = NULL;
 	tty->pgrp = NULL;
 	mutex_init(&tty->legacy_mutex);
-	mutex_init(&tty->termios_mutex);
-	mutex_init(&tty->ldisc_mutex);
+	mutex_init(&tty->throttle_mutex);
+	init_rwsem(&tty->termios_rwsem);
+	mutex_init(&tty->winsize_mutex);
+	init_ldsem(&tty->ldisc_sem);
 	init_waitqueue_head(&tty->write_wait);
 	init_waitqueue_head(&tty->read_wait);
 	INIT_WORK(&tty->hangup_work, do_tty_hangup);
diff --git a/drivers/tty/tty_ioctl.c b/drivers/tty/tty_ioctl.c
index 3500d411414..03ba081c577 100644
--- a/drivers/tty/tty_ioctl.c
+++ b/drivers/tty/tty_ioctl.c
@@ -94,20 +94,20 @@ EXPORT_SYMBOL(tty_driver_flush_buffer);
  *	@tty: terminal
  *
  *	Indicate that a tty should stop transmitting data down the stack.
- *	Takes the termios mutex to protect against parallel throttle/unthrottle
+ *	Takes the termios rwsem to protect against parallel throttle/unthrottle
  *	and also to ensure the driver can consistently reference its own
  *	termios data at this point when implementing software flow control.
  */
 
 void tty_throttle(struct tty_struct *tty)
 {
-	mutex_lock(&tty->termios_mutex);
+	down_write(&tty->termios_rwsem);
 	/* check TTY_THROTTLED first so it indicates our state */
 	if (!test_and_set_bit(TTY_THROTTLED, &tty->flags) &&
 	    tty->ops->throttle)
 		tty->ops->throttle(tty);
 	tty->flow_change = 0;
-	mutex_unlock(&tty->termios_mutex);
+	up_write(&tty->termios_rwsem);
 }
 EXPORT_SYMBOL(tty_throttle);
 
@@ -116,7 +116,7 @@ EXPORT_SYMBOL(tty_throttle);
  *	@tty: terminal
  *
  *	Indicate that a tty may continue transmitting data down the stack.
- *	Takes the termios mutex to protect against parallel throttle/unthrottle
+ *	Takes the termios rwsem to protect against parallel throttle/unthrottle
  *	and also to ensure the driver can consistently reference its own
  *	termios data at this point when implementing software flow control.
  *
@@ -126,12 +126,12 @@ EXPORT_SYMBOL(tty_throttle);
 
 void tty_unthrottle(struct tty_struct *tty)
 {
-	mutex_lock(&tty->termios_mutex);
+	down_write(&tty->termios_rwsem);
 	if (test_and_clear_bit(TTY_THROTTLED, &tty->flags) &&
 	    tty->ops->unthrottle)
 		tty->ops->unthrottle(tty);
 	tty->flow_change = 0;
-	mutex_unlock(&tty->termios_mutex);
+	up_write(&tty->termios_rwsem);
 }
 EXPORT_SYMBOL(tty_unthrottle);
 
@@ -151,7 +151,7 @@ int tty_throttle_safe(struct tty_struct *tty)
 {
 	int ret = 0;
 
-	mutex_lock(&tty->termios_mutex);
+	mutex_lock(&tty->throttle_mutex);
 	if (!test_bit(TTY_THROTTLED, &tty->flags)) {
 		if (tty->flow_change != TTY_THROTTLE_SAFE)
 			ret = 1;
@@ -161,7 +161,7 @@ int tty_throttle_safe(struct tty_struct *tty)
 				tty->ops->throttle(tty);
 		}
 	}
-	mutex_unlock(&tty->termios_mutex);
+	mutex_unlock(&tty->throttle_mutex);
 
 	return ret;
 }
@@ -182,7 +182,7 @@ int tty_unthrottle_safe(struct tty_struct *tty)
 {
 	int ret = 0;
 
-	mutex_lock(&tty->termios_mutex);
+	mutex_lock(&tty->throttle_mutex);
 	if (test_bit(TTY_THROTTLED, &tty->flags)) {
 		if (tty->flow_change != TTY_UNTHROTTLE_SAFE)
 			ret = 1;
@@ -192,7 +192,7 @@ int tty_unthrottle_safe(struct tty_struct *tty)
 				tty->ops->unthrottle(tty);
 		}
 	}
-	mutex_unlock(&tty->termios_mutex);
+	mutex_unlock(&tty->throttle_mutex);
 
 	return ret;
 }
@@ -468,7 +468,7 @@ EXPORT_SYMBOL_GPL(tty_termios_encode_baud_rate);
  *	@obad: output baud rate
  *
  *	Update the current termios data for the tty with the new speed
- *	settings. The caller must hold the termios_mutex for the tty in
+ *	settings. The caller must hold the termios_rwsem for the tty in
  *	question.
  */
 
@@ -528,7 +528,7 @@ EXPORT_SYMBOL(tty_termios_hw_change);
  *	is a bit of layering violation here with n_tty in terms of the
  *	internal knowledge of this function.
  *
- *	Locking: termios_mutex
+ *	Locking: termios_rwsem
  */
 
 int tty_set_termios(struct tty_struct *tty, struct ktermios *new_termios)
@@ -544,7 +544,7 @@ int tty_set_termios(struct tty_struct *tty, struct ktermios *new_termios)
 
 	/* FIXME: we need to decide on some locking/ordering semantics
 	   for the set_termios notification eventually */
-	mutex_lock(&tty->termios_mutex);
+	down_write(&tty->termios_rwsem);
 	old_termios = tty->termios;
 	tty->termios = *new_termios;
 	unset_locked_termios(&tty->termios, &old_termios, &tty->termios_locked);
@@ -586,7 +586,7 @@ int tty_set_termios(struct tty_struct *tty, struct ktermios *new_termios)
 			(ld->ops->set_termios)(tty, &old_termios);
 		tty_ldisc_deref(ld);
 	}
-	mutex_unlock(&tty->termios_mutex);
+	up_write(&tty->termios_rwsem);
 	return 0;
 }
 EXPORT_SYMBOL_GPL(tty_set_termios);
@@ -601,7 +601,7 @@ EXPORT_SYMBOL_GPL(tty_set_termios);
  *	functions before using tty_set_termios to do the actual changes.
  *
  *	Locking:
- *		Called functions take ldisc and termios_mutex locks
+ *		Called functions take ldisc and termios_rwsem locks
  */
 
 static int set_termios(struct tty_struct *tty, void __user *arg, int opt)
@@ -613,9 +613,9 @@ static int set_termios(struct tty_struct *tty, void __user *arg, int opt)
 	if (retval)
 		return retval;
 
-	mutex_lock(&tty->termios_mutex);
+	down_read(&tty->termios_rwsem);
 	tmp_termios = tty->termios;
-	mutex_unlock(&tty->termios_mutex);
+	up_read(&tty->termios_rwsem);
 
 	if (opt & TERMIOS_TERMIO) {
 		if (user_termio_to_kernel_termios(&tmp_termios,
@@ -667,16 +667,16 @@ static int set_termios(struct tty_struct *tty, void __user *arg, int opt)
 
 static void copy_termios(struct tty_struct *tty, struct ktermios *kterm)
 {
-	mutex_lock(&tty->termios_mutex);
+	down_read(&tty->termios_rwsem);
 	*kterm = tty->termios;
-	mutex_unlock(&tty->termios_mutex);
+	up_read(&tty->termios_rwsem);
 }
 
 static void copy_termios_locked(struct tty_struct *tty, struct ktermios *kterm)
 {
-	mutex_lock(&tty->termios_mutex);
+	down_read(&tty->termios_rwsem);
 	*kterm = tty->termios_locked;
-	mutex_unlock(&tty->termios_mutex);
+	up_read(&tty->termios_rwsem);
 }
 
 static int get_termio(struct tty_struct *tty, struct termio __user *termio)
@@ -723,10 +723,10 @@ static int set_termiox(struct tty_struct *tty, void __user *arg, int opt)
 			return -ERESTARTSYS;
 	}
 
-	mutex_lock(&tty->termios_mutex);
+	down_write(&tty->termios_rwsem);
 	if (tty->ops->set_termiox)
 		tty->ops->set_termiox(tty, &tnew);
-	mutex_unlock(&tty->termios_mutex);
+	up_write(&tty->termios_rwsem);
 	return 0;
 }
 
@@ -761,13 +761,13 @@ static int get_sgttyb(struct tty_struct *tty, struct sgttyb __user *sgttyb)
 {
 	struct sgttyb tmp;
 
-	mutex_lock(&tty->termios_mutex);
+	down_read(&tty->termios_rwsem);
 	tmp.sg_ispeed = tty->termios.c_ispeed;
 	tmp.sg_ospeed = tty->termios.c_ospeed;
 	tmp.sg_erase = tty->termios.c_cc[VERASE];
 	tmp.sg_kill = tty->termios.c_cc[VKILL];
 	tmp.sg_flags = get_sgflags(tty);
-	mutex_unlock(&tty->termios_mutex);
+	up_read(&tty->termios_rwsem);
 
 	return copy_to_user(sgttyb, &tmp, sizeof(tmp)) ? -EFAULT : 0;
 }
@@ -806,7 +806,7 @@ static void set_sgflags(struct ktermios *termios, int flags)
  *	Updates a terminal from the legacy BSD style terminal information
  *	structure.
  *
- *	Locking: termios_mutex
+ *	Locking: termios_rwsem
  */
 
 static int set_sgttyb(struct tty_struct *tty, struct sgttyb __user *sgttyb)
@@ -822,7 +822,7 @@ static int set_sgttyb(struct tty_struct *tty, struct sgttyb __user *sgttyb)
 	if (copy_from_user(&tmp, sgttyb, sizeof(tmp)))
 		return -EFAULT;
 
-	mutex_lock(&tty->termios_mutex);
+	down_write(&tty->termios_rwsem);
 	termios = tty->termios;
 	termios.c_cc[VERASE] = tmp.sg_erase;
 	termios.c_cc[VKILL] = tmp.sg_kill;
@@ -832,7 +832,7 @@ static int set_sgttyb(struct tty_struct *tty, struct sgttyb __user *sgttyb)
 	tty_termios_encode_baud_rate(&termios, termios.c_ispeed,
 						termios.c_ospeed);
 #endif
-	mutex_unlock(&tty->termios_mutex);
+	up_write(&tty->termios_rwsem);
 	tty_set_termios(tty, &termios);
 	return 0;
 }
@@ -843,14 +843,14 @@ static int get_tchars(struct tty_struct *tty, struct tchars __user *tchars)
 {
 	struct tchars tmp;
 
-	mutex_lock(&tty->termios_mutex);
+	down_read(&tty->termios_rwsem);
 	tmp.t_intrc = tty->termios.c_cc[VINTR];
 	tmp.t_quitc = tty->termios.c_cc[VQUIT];
 	tmp.t_startc = tty->termios.c_cc[VSTART];
 	tmp.t_stopc = tty->termios.c_cc[VSTOP];
 	tmp.t_eofc = tty->termios.c_cc[VEOF];
 	tmp.t_brkc = tty->termios.c_cc[VEOL2];	/* what is brkc anyway? */
-	mutex_unlock(&tty->termios_mutex);
+	up_read(&tty->termios_rwsem);
 	return copy_to_user(tchars, &tmp, sizeof(tmp)) ? -EFAULT : 0;
 }
 
@@ -860,14 +860,14 @@ static int set_tchars(struct tty_struct *tty, struct tchars __user *tchars)
 
 	if (copy_from_user(&tmp, tchars, sizeof(tmp)))
 		return -EFAULT;
-	mutex_lock(&tty->termios_mutex);
+	down_write(&tty->termios_rwsem);
 	tty->termios.c_cc[VINTR] = tmp.t_intrc;
 	tty->termios.c_cc[VQUIT] = tmp.t_quitc;
 	tty->termios.c_cc[VSTART] = tmp.t_startc;
 	tty->termios.c_cc[VSTOP] = tmp.t_stopc;
 	tty->termios.c_cc[VEOF] = tmp.t_eofc;
 	tty->termios.c_cc[VEOL2] = tmp.t_brkc;	/* what is brkc anyway? */
-	mutex_unlock(&tty->termios_mutex);
+	up_write(&tty->termios_rwsem);
 	return 0;
 }
 #endif
@@ -877,7 +877,7 @@ static int get_ltchars(struct tty_struct *tty, struct ltchars __user *ltchars)
 {
 	struct ltchars tmp;
 
-	mutex_lock(&tty->termios_mutex);
+	down_read(&tty->termios_rwsem);
 	tmp.t_suspc = tty->termios.c_cc[VSUSP];
 	/* what is dsuspc anyway? */
 	tmp.t_dsuspc = tty->termios.c_cc[VSUSP];
@@ -886,7 +886,7 @@ static int get_ltchars(struct tty_struct *tty, struct ltchars __user *ltchars)
 	tmp.t_flushc = tty->termios.c_cc[VEOL2];
 	tmp.t_werasc = tty->termios.c_cc[VWERASE];
 	tmp.t_lnextc = tty->termios.c_cc[VLNEXT];
-	mutex_unlock(&tty->termios_mutex);
+	up_read(&tty->termios_rwsem);
 	return copy_to_user(ltchars, &tmp, sizeof(tmp)) ? -EFAULT : 0;
 }
 
@@ -897,7 +897,7 @@ static int set_ltchars(struct tty_struct *tty, struct ltchars __user *ltchars)
 	if (copy_from_user(&tmp, ltchars, sizeof(tmp)))
 		return -EFAULT;
 
-	mutex_lock(&tty->termios_mutex);
+	down_write(&tty->termios_rwsem);
 	tty->termios.c_cc[VSUSP] = tmp.t_suspc;
 	/* what is dsuspc anyway? */
 	tty->termios.c_cc[VEOL2] = tmp.t_dsuspc;
@@ -906,7 +906,7 @@ static int set_ltchars(struct tty_struct *tty, struct ltchars __user *ltchars)
 	tty->termios.c_cc[VEOL2] = tmp.t_flushc;
 	tty->termios.c_cc[VWERASE] = tmp.t_werasc;
 	tty->termios.c_cc[VLNEXT] = tmp.t_lnextc;
-	mutex_unlock(&tty->termios_mutex);
+	up_write(&tty->termios_rwsem);
 	return 0;
 }
 #endif
@@ -946,7 +946,7 @@ static int send_prio_char(struct tty_struct *tty, char ch)
  *	@arg: enable/disable CLOCAL
  *
  *	Perform a change to the CLOCAL state and call into the driver
- *	layer to make it visible. All done with the termios mutex
+ *	layer to make it visible. All done with the termios rwsem
  */
 
 static int tty_change_softcar(struct tty_struct *tty, int arg)
@@ -955,7 +955,7 @@ static int tty_change_softcar(struct tty_struct *tty, int arg)
 	int bit = arg ? CLOCAL : 0;
 	struct ktermios old;
 
-	mutex_lock(&tty->termios_mutex);
+	down_write(&tty->termios_rwsem);
 	old = tty->termios;
 	tty->termios.c_cflag &= ~CLOCAL;
 	tty->termios.c_cflag |= bit;
@@ -963,7 +963,7 @@ static int tty_change_softcar(struct tty_struct *tty, int arg)
 		tty->ops->set_termios(tty, &old);
 	if ((tty->termios.c_cflag & CLOCAL) != bit)
 		ret = -EINVAL;
-	mutex_unlock(&tty->termios_mutex);
+	up_write(&tty->termios_rwsem);
 	return ret;
 }
 
@@ -1066,9 +1066,9 @@ int tty_mode_ioctl(struct tty_struct *tty, struct file *file,
 		if (user_termios_to_kernel_termios(&kterm,
 					       (struct termios __user *) arg))
 			return -EFAULT;
-		mutex_lock(&real_tty->termios_mutex);
+		down_write(&real_tty->termios_rwsem);
 		real_tty->termios_locked = kterm;
-		mutex_unlock(&real_tty->termios_mutex);
+		up_write(&real_tty->termios_rwsem);
 		return 0;
 #else
 	case TIOCGLCKTRMIOS:
@@ -1083,9 +1083,9 @@ int tty_mode_ioctl(struct tty_struct *tty, struct file *file,
 		if (user_termios_to_kernel_termios_1(&kterm,
 					       (struct termios __user *) arg))
 			return -EFAULT;
-		mutex_lock(&real_tty->termios_mutex);
+		down_write(&real_tty->termios_rwsem);
 		real_tty->termios_locked = kterm;
-		mutex_unlock(&real_tty->termios_mutex);
+		up_write(&real_tty->termios_rwsem);
 		return ret;
 #endif
 #ifdef TCGETX
@@ -1093,9 +1093,9 @@ int tty_mode_ioctl(struct tty_struct *tty, struct file *file,
 		struct termiox ktermx;
 		if (real_tty->termiox == NULL)
 			return -EINVAL;
-		mutex_lock(&real_tty->termios_mutex);
+		down_read(&real_tty->termios_rwsem);
 		memcpy(&ktermx, real_tty->termiox, sizeof(struct termiox));
-		mutex_unlock(&real_tty->termios_mutex);
+		up_read(&real_tty->termios_rwsem);
 		if (copy_to_user(p, &ktermx, sizeof(struct termiox)))
 			ret = -EFAULT;
 		return ret;
diff --git a/drivers/tty/tty_ldisc.c b/drivers/tty/tty_ldisc.c
index 1afe192bef6..6458e11e8e9 100644
--- a/drivers/tty/tty_ldisc.c
+++ b/drivers/tty/tty_ldisc.c
@@ -31,14 +31,20 @@
 #define tty_ldisc_debug(tty, f, args...)
 #endif
 
+/* lockdep nested classes for tty->ldisc_sem */
+enum {
+	LDISC_SEM_NORMAL,
+	LDISC_SEM_OTHER,
+};
+
+
 /*
  *	This guards the refcounted line discipline lists. The lock
  *	must be taken with irqs off because there are hangup path
  *	callers who will do ldisc lookups and cannot sleep.
  */
 
-static DEFINE_RAW_SPINLOCK(tty_ldisc_lock);
-static DECLARE_WAIT_QUEUE_HEAD(tty_ldisc_wait);
+static DEFINE_RAW_SPINLOCK(tty_ldiscs_lock);
 /* Line disc dispatch table */
 static struct tty_ldisc_ops *tty_ldiscs[NR_LDISCS];
 
@@ -52,7 +58,7 @@ static struct tty_ldisc_ops *tty_ldiscs[NR_LDISCS];
  *	from this point onwards.
  *
  *	Locking:
- *		takes tty_ldisc_lock to guard against ldisc races
+ *		takes tty_ldiscs_lock to guard against ldisc races
  */
 
 int tty_register_ldisc(int disc, struct tty_ldisc_ops *new_ldisc)
@@ -63,11 +69,11 @@ int tty_register_ldisc(int disc, struct tty_ldisc_ops *new_ldisc)
 	if (disc < N_TTY || disc >= NR_LDISCS)
 		return -EINVAL;
 
-	raw_spin_lock_irqsave(&tty_ldisc_lock, flags);
+	raw_spin_lock_irqsave(&tty_ldiscs_lock, flags);
 	tty_ldiscs[disc] = new_ldisc;
 	new_ldisc->num = disc;
 	new_ldisc->refcount = 0;
-	raw_spin_unlock_irqrestore(&tty_ldisc_lock, flags);
+	raw_spin_unlock_irqrestore(&tty_ldiscs_lock, flags);
 
 	return ret;
 }
@@ -82,7 +88,7 @@ EXPORT_SYMBOL(tty_register_ldisc);
  *	currently in use.
  *
  *	Locking:
- *		takes tty_ldisc_lock to guard against ldisc races
+ *		takes tty_ldiscs_lock to guard against ldisc races
  */
 
 int tty_unregister_ldisc(int disc)
@@ -93,12 +99,12 @@ int tty_unregister_ldisc(int disc)
 	if (disc < N_TTY || disc >= NR_LDISCS)
 		return -EINVAL;
 
-	raw_spin_lock_irqsave(&tty_ldisc_lock, flags);
+	raw_spin_lock_irqsave(&tty_ldiscs_lock, flags);
 	if (tty_ldiscs[disc]->refcount)
 		ret = -EBUSY;
 	else
 		tty_ldiscs[disc] = NULL;
-	raw_spin_unlock_irqrestore(&tty_ldisc_lock, flags);
+	raw_spin_unlock_irqrestore(&tty_ldiscs_lock, flags);
 
 	return ret;
 }
@@ -109,7 +115,7 @@ static struct tty_ldisc_ops *get_ldops(int disc)
 	unsigned long flags;
 	struct tty_ldisc_ops *ldops, *ret;
 
-	raw_spin_lock_irqsave(&tty_ldisc_lock, flags);
+	raw_spin_lock_irqsave(&tty_ldiscs_lock, flags);
 	ret = ERR_PTR(-EINVAL);
 	ldops = tty_ldiscs[disc];
 	if (ldops) {
@@ -119,7 +125,7 @@ static struct tty_ldisc_ops *get_ldops(int disc)
 			ret = ldops;
 		}
 	}
-	raw_spin_unlock_irqrestore(&tty_ldisc_lock, flags);
+	raw_spin_unlock_irqrestore(&tty_ldiscs_lock, flags);
 	return ret;
 }
 
@@ -127,10 +133,10 @@ static void put_ldops(struct tty_ldisc_ops *ldops)
 {
 	unsigned long flags;
 
-	raw_spin_lock_irqsave(&tty_ldisc_lock, flags);
+	raw_spin_lock_irqsave(&tty_ldiscs_lock, flags);
 	ldops->refcount--;
 	module_put(ldops->owner);
-	raw_spin_unlock_irqrestore(&tty_ldisc_lock, flags);
+	raw_spin_unlock_irqrestore(&tty_ldiscs_lock, flags);
 }
 
 /**
@@ -143,10 +149,10 @@ static void put_ldops(struct tty_ldisc_ops *ldops)
  *	available
  *
  *	Locking:
- *		takes tty_ldisc_lock to guard against ldisc races
+ *		takes tty_ldiscs_lock to guard against ldisc races
  */
 
-static struct tty_ldisc *tty_ldisc_get(int disc)
+static struct tty_ldisc *tty_ldisc_get(struct tty_struct *tty, int disc)
 {
 	struct tty_ldisc *ld;
 	struct tty_ldisc_ops *ldops;
@@ -173,8 +179,7 @@ static struct tty_ldisc *tty_ldisc_get(int disc)
 	}
 
 	ld->ops = ldops;
-	atomic_set(&ld->users, 1);
-	init_waitqueue_head(&ld->wq_idle);
+	ld->tty = tty;
 
 	return ld;
 }
@@ -186,20 +191,11 @@ static struct tty_ldisc *tty_ldisc_get(int disc)
  */
 static inline void tty_ldisc_put(struct tty_ldisc *ld)
 {
-	unsigned long flags;
-
 	if (WARN_ON_ONCE(!ld))
 		return;
 
-	raw_spin_lock_irqsave(&tty_ldisc_lock, flags);
-
-	/* unreleased reader reference(s) will cause this WARN */
-	WARN_ON(!atomic_dec_and_test(&ld->users));
-
-	ld->ops->refcount--;
-	module_put(ld->ops->owner);
+	put_ldops(ld->ops);
 	kfree(ld);
-	raw_spin_unlock_irqrestore(&tty_ldisc_lock, flags);
 }
 
 static void *tty_ldiscs_seq_start(struct seq_file *m, loff_t *pos)
@@ -251,34 +247,6 @@ const struct file_operations tty_ldiscs_proc_fops = {
 };
 
 /**
- *	tty_ldisc_try		-	internal helper
- *	@tty: the tty
- *
- *	Make a single attempt to grab and bump the refcount on
- *	the tty ldisc. Return 0 on failure or 1 on success. This is
- *	used to implement both the waiting and non waiting versions
- *	of tty_ldisc_ref
- *
- *	Locking: takes tty_ldisc_lock
- */
-
-static struct tty_ldisc *tty_ldisc_try(struct tty_struct *tty)
-{
-	unsigned long flags;
-	struct tty_ldisc *ld;
-
-	/* FIXME: this allows reference acquire after TTY_LDISC is cleared */
-	raw_spin_lock_irqsave(&tty_ldisc_lock, flags);
-	ld = NULL;
-	if (test_bit(TTY_LDISC, &tty->flags) && tty->ldisc) {
-		ld = tty->ldisc;
-		atomic_inc(&ld->users);
-	}
-	raw_spin_unlock_irqrestore(&tty_ldisc_lock, flags);
-	return ld;
-}
-
-/**
  *	tty_ldisc_ref_wait	-	wait for the tty ldisc
  *	@tty: tty device
  *
@@ -291,16 +259,15 @@ static struct tty_ldisc *tty_ldisc_try(struct tty_struct *tty)
  *	against a discipline change, such as an existing ldisc reference
  *	(which we check for)
  *
- *	Locking: call functions take tty_ldisc_lock
+ *	Note: only callable from a file_operations routine (which
+ *	guarantees tty->ldisc != NULL when the lock is acquired).
  */
 
 struct tty_ldisc *tty_ldisc_ref_wait(struct tty_struct *tty)
 {
-	struct tty_ldisc *ld;
-
-	/* wait_event is a macro */
-	wait_event(tty_ldisc_wait, (ld = tty_ldisc_try(tty)) != NULL);
-	return ld;
+	ldsem_down_read(&tty->ldisc_sem, MAX_SCHEDULE_TIMEOUT);
+	WARN_ON(!tty->ldisc);
+	return tty->ldisc;
 }
 EXPORT_SYMBOL_GPL(tty_ldisc_ref_wait);
 
@@ -311,13 +278,18 @@ EXPORT_SYMBOL_GPL(tty_ldisc_ref_wait);
  *	Dereference the line discipline for the terminal and take a
  *	reference to it. If the line discipline is in flux then
  *	return NULL. Can be called from IRQ and timer functions.
- *
- *	Locking: called functions take tty_ldisc_lock
  */
 
 struct tty_ldisc *tty_ldisc_ref(struct tty_struct *tty)
 {
-	return tty_ldisc_try(tty);
+	struct tty_ldisc *ld = NULL;
+
+	if (ldsem_down_read_trylock(&tty->ldisc_sem)) {
+		ld = tty->ldisc;
+		if (!ld)
+			ldsem_up_read(&tty->ldisc_sem);
+	}
+	return ld;
 }
 EXPORT_SYMBOL_GPL(tty_ldisc_ref);
 
@@ -327,48 +299,91 @@ EXPORT_SYMBOL_GPL(tty_ldisc_ref);
  *
  *	Undoes the effect of tty_ldisc_ref or tty_ldisc_ref_wait. May
  *	be called in IRQ context.
- *
- *	Locking: takes tty_ldisc_lock
  */
 
 void tty_ldisc_deref(struct tty_ldisc *ld)
 {
-	unsigned long flags;
+	ldsem_up_read(&ld->tty->ldisc_sem);
+}
+EXPORT_SYMBOL_GPL(tty_ldisc_deref);
 
-	if (WARN_ON_ONCE(!ld))
-		return;
 
-	raw_spin_lock_irqsave(&tty_ldisc_lock, flags);
-	/*
-	 * WARNs if one-too-many reader references were released
-	 * - the last reference must be released with tty_ldisc_put
-	 */
-	WARN_ON(atomic_dec_and_test(&ld->users));
-	raw_spin_unlock_irqrestore(&tty_ldisc_lock, flags);
+static inline int __lockfunc
+tty_ldisc_lock(struct tty_struct *tty, unsigned long timeout)
+{
+	return ldsem_down_write(&tty->ldisc_sem, timeout);
+}
 
-	if (waitqueue_active(&ld->wq_idle))
-		wake_up(&ld->wq_idle);
+static inline int __lockfunc
+tty_ldisc_lock_nested(struct tty_struct *tty, unsigned long timeout)
+{
+	return ldsem_down_write_nested(&tty->ldisc_sem,
+				       LDISC_SEM_OTHER, timeout);
 }
-EXPORT_SYMBOL_GPL(tty_ldisc_deref);
 
-/**
- *	tty_ldisc_enable	-	allow ldisc use
- *	@tty: terminal to activate ldisc on
- *
- *	Set the TTY_LDISC flag when the line discipline can be called
- *	again. Do necessary wakeups for existing sleepers. Clear the LDISC
- *	changing flag to indicate any ldisc change is now over.
- *
- *	Note: nobody should set the TTY_LDISC bit except via this function.
- *	Clearing directly is allowed.
- */
+static inline void tty_ldisc_unlock(struct tty_struct *tty)
+{
+	return ldsem_up_write(&tty->ldisc_sem);
+}
 
-static void tty_ldisc_enable(struct tty_struct *tty)
+static int __lockfunc
+tty_ldisc_lock_pair_timeout(struct tty_struct *tty, struct tty_struct *tty2,
+			    unsigned long timeout)
+{
+	int ret;
+
+	if (tty < tty2) {
+		ret = tty_ldisc_lock(tty, timeout);
+		if (ret) {
+			ret = tty_ldisc_lock_nested(tty2, timeout);
+			if (!ret)
+				tty_ldisc_unlock(tty);
+		}
+	} else {
+		/* if this is possible, it has lots of implications */
+		WARN_ON_ONCE(tty == tty2);
+		if (tty2 && tty != tty2) {
+			ret = tty_ldisc_lock(tty2, timeout);
+			if (ret) {
+				ret = tty_ldisc_lock_nested(tty, timeout);
+				if (!ret)
+					tty_ldisc_unlock(tty2);
+			}
+		} else
+			ret = tty_ldisc_lock(tty, timeout);
+	}
+
+	if (!ret)
+		return -EBUSY;
+
+	set_bit(TTY_LDISC_HALTED, &tty->flags);
+	if (tty2)
+		set_bit(TTY_LDISC_HALTED, &tty2->flags);
+	return 0;
+}
+
+static void __lockfunc
+tty_ldisc_lock_pair(struct tty_struct *tty, struct tty_struct *tty2)
+{
+	tty_ldisc_lock_pair_timeout(tty, tty2, MAX_SCHEDULE_TIMEOUT);
+}
+
+static void __lockfunc tty_ldisc_unlock_pair(struct tty_struct *tty,
+					     struct tty_struct *tty2)
+{
+	tty_ldisc_unlock(tty);
+	if (tty2)
+		tty_ldisc_unlock(tty2);
+}
+
+static void __lockfunc tty_ldisc_enable_pair(struct tty_struct *tty,
+					     struct tty_struct *tty2)
 {
 	clear_bit(TTY_LDISC_HALTED, &tty->flags);
-	set_bit(TTY_LDISC, &tty->flags);
-	clear_bit(TTY_LDISC_CHANGING, &tty->flags);
-	wake_up(&tty_ldisc_wait);
+	if (tty2)
+		clear_bit(TTY_LDISC_HALTED, &tty2->flags);
+
+	tty_ldisc_unlock_pair(tty, tty2);
 }
 
 /**
@@ -400,14 +415,14 @@ EXPORT_SYMBOL_GPL(tty_ldisc_flush);
  *	they are not on hot paths so a little discipline won't do
  *	any harm.
  *
- *	Locking: takes termios_mutex
+ *	Locking: takes termios_rwsem
  */
 
 static void tty_set_termios_ldisc(struct tty_struct *tty, int num)
 {
-	mutex_lock(&tty->termios_mutex);
+	down_write(&tty->termios_rwsem);
 	tty->termios.c_line = num;
-	mutex_unlock(&tty->termios_mutex);
+	up_write(&tty->termios_rwsem);
 }
 
 /**
@@ -468,14 +483,14 @@ static void tty_ldisc_restore(struct tty_struct *tty, struct tty_ldisc *old)
 	int r;
 
 	/* There is an outstanding reference here so this is safe */
-	old = tty_ldisc_get(old->ops->num);
+	old = tty_ldisc_get(tty, old->ops->num);
 	WARN_ON(IS_ERR(old));
 	tty->ldisc = old;
 	tty_set_termios_ldisc(tty, old->ops->num);
 	if (tty_ldisc_open(tty, old) < 0) {
 		tty_ldisc_put(old);
 		/* This driver is always present */
-		new_ldisc = tty_ldisc_get(N_TTY);
+		new_ldisc = tty_ldisc_get(tty, N_TTY);
 		if (IS_ERR(new_ldisc))
 			panic("n_tty: get");
 		tty->ldisc = new_ldisc;
@@ -489,101 +504,6 @@ static void tty_ldisc_restore(struct tty_struct *tty, struct tty_ldisc *old)
 }
 
 /**
- *	tty_ldisc_wait_idle	-	wait for the ldisc to become idle
- *	@tty: tty to wait for
- *	@timeout: for how long to wait at most
- *
- *	Wait for the line discipline to become idle. The discipline must
- *	have been halted for this to guarantee it remains idle.
- */
-static int tty_ldisc_wait_idle(struct tty_struct *tty, long timeout)
-{
-	long ret;
-	ret = wait_event_timeout(tty->ldisc->wq_idle,
-			atomic_read(&tty->ldisc->users) == 1, timeout);
-	return ret > 0 ? 0 : -EBUSY;
-}
-
-/**
- *	tty_ldisc_halt		-	shut down the line discipline
- *	@tty: tty device
- *	@o_tty: paired pty device (can be NULL)
- *	@timeout: # of jiffies to wait for ldisc refs to be released
- *
- *	Shut down the line discipline and work queue for this tty device and
- *	its paired pty (if exists). Clearing the TTY_LDISC flag ensures
- *	no further references can be obtained, while waiting for existing
- *	references to be released ensures no more data is fed to the ldisc.
- *
- *	You need to do a 'flush_scheduled_work()' (outside the ldisc_mutex)
- *	in order to make sure any currently executing ldisc work is also
- *	flushed.
- */
-
-static int tty_ldisc_halt(struct tty_struct *tty, struct tty_struct *o_tty,
-			  long timeout)
-{
-	int retval;
-
-	clear_bit(TTY_LDISC, &tty->flags);
-	if (o_tty)
-		clear_bit(TTY_LDISC, &o_tty->flags);
-
-	retval = tty_ldisc_wait_idle(tty, timeout);
-	if (!retval && o_tty)
-		retval = tty_ldisc_wait_idle(o_tty, timeout);
-	if (retval)
-		return retval;
-
-	set_bit(TTY_LDISC_HALTED, &tty->flags);
-	if (o_tty)
-		set_bit(TTY_LDISC_HALTED, &o_tty->flags);
-
-	return 0;
-}
-
-/**
- *	tty_ldisc_hangup_halt - halt the line discipline for hangup
- *	@tty: tty being hung up
- *
- *	Shut down the line discipline and work queue for the tty device
- *	being hungup. Clear the TTY_LDISC flag to ensure no further
- *	references can be obtained and wait for remaining references to be
- *	released to ensure no more data is fed to this ldisc.
- *	Caller must hold legacy and ->ldisc_mutex.
- *
- *	NB: tty_set_ldisc() is prevented from changing the ldisc concurrently
- *	with this function by checking the TTY_HUPPING flag.
- */
-static bool tty_ldisc_hangup_halt(struct tty_struct *tty)
-{
-	char cur_n[TASK_COMM_LEN], tty_n[64];
-	long timeout = 3 * HZ;
-
-	clear_bit(TTY_LDISC, &tty->flags);
-
-	if (tty->ldisc) {	/* Not yet closed */
-		tty_unlock(tty);
-
-		while (tty_ldisc_wait_idle(tty, timeout) == -EBUSY) {
-			timeout = MAX_SCHEDULE_TIMEOUT;
-			printk_ratelimited(KERN_WARNING
-				"%s: waiting (%s) for %s took too long, but we keep waiting...\n",
-				__func__, get_task_comm(cur_n, current),
-				tty_name(tty, tty_n));
-		}
-
-		set_bit(TTY_LDISC_HALTED, &tty->flags);
-
-		/* must reacquire both locks and preserve lock order */
-		mutex_unlock(&tty->ldisc_mutex);
-		tty_lock(tty);
-		mutex_lock(&tty->ldisc_mutex);
-	}
-	return !!tty->ldisc;
-}
-
-/**
  *	tty_set_ldisc		-	set line discipline
  *	@tty: the terminal to set
  *	@ldisc: the line discipline
@@ -592,110 +512,49 @@ static bool tty_ldisc_hangup_halt(struct tty_struct *tty)
  *	context. The ldisc change logic has to protect itself against any
  *	overlapping ldisc change (including on the other end of pty pairs),
  *	the close of one side of a tty/pty pair, and eventually hangup.
- *
- *	Locking: takes tty_ldisc_lock, termios_mutex
  */
 
 int tty_set_ldisc(struct tty_struct *tty, int ldisc)
 {
 	int retval;
-	struct tty_ldisc *o_ldisc, *new_ldisc;
-	struct tty_struct *o_tty;
+	struct tty_ldisc *old_ldisc, *new_ldisc;
+	struct tty_struct *o_tty = tty->link;
 
-	new_ldisc = tty_ldisc_get(ldisc);
+	new_ldisc = tty_ldisc_get(tty, ldisc);
 	if (IS_ERR(new_ldisc))
 		return PTR_ERR(new_ldisc);
 
-	tty_lock(tty);
-	/*
-	 *	We need to look at the tty locking here for pty/tty pairs
-	 *	when both sides try to change in parallel.
-	 */
-
-	o_tty = tty->link;	/* o_tty is the pty side or NULL */
-
+	retval = tty_ldisc_lock_pair_timeout(tty, o_tty, 5 * HZ);
+	if (retval) {
+		tty_ldisc_put(new_ldisc);
+		return retval;
+	}
 
 	/*
 	 *	Check the no-op case
 	 */
 
 	if (tty->ldisc->ops->num == ldisc) {
-		tty_unlock(tty);
+		tty_ldisc_enable_pair(tty, o_tty);
 		tty_ldisc_put(new_ldisc);
 		return 0;
 	}
 
-	mutex_lock(&tty->ldisc_mutex);
-
-	/*
-	 *	We could be midstream of another ldisc change which has
-	 *	dropped the lock during processing. If so we need to wait.
-	 */
-
-	while (test_bit(TTY_LDISC_CHANGING, &tty->flags)) {
-		mutex_unlock(&tty->ldisc_mutex);
-		tty_unlock(tty);
-		wait_event(tty_ldisc_wait,
-			test_bit(TTY_LDISC_CHANGING, &tty->flags) == 0);
-		tty_lock(tty);
-		mutex_lock(&tty->ldisc_mutex);
-	}
-
-	set_bit(TTY_LDISC_CHANGING, &tty->flags);
-
-	/*
-	 *	No more input please, we are switching. The new ldisc
-	 *	will update this value in the ldisc open function
-	 */
-
-	tty->receive_room = 0;
-
-	o_ldisc = tty->ldisc;
-
-	tty_unlock(tty);
-	/*
-	 *	Make sure we don't change while someone holds a
-	 *	reference to the line discipline. The TTY_LDISC bit
-	 *	prevents anyone taking a reference once it is clear.
-	 *	We need the lock to avoid racing reference takers.
-	 *
-	 *	We must clear the TTY_LDISC bit here to avoid a livelock
-	 *	with a userspace app continually trying to use the tty in
-	 *	parallel to the change and re-referencing the tty.
-	 */
-
-	retval = tty_ldisc_halt(tty, o_tty, 5 * HZ);
-
-	/*
-	 * Wait for hangup to complete, if pending.
-	 * We must drop the mutex here in case a hangup is also in process.
-	 */
-
-	mutex_unlock(&tty->ldisc_mutex);
-
-	flush_work(&tty->hangup_work);
-
+	old_ldisc = tty->ldisc;
 	tty_lock(tty);
-	mutex_lock(&tty->ldisc_mutex);
-
-	/* handle wait idle failure locked */
-	if (retval) {
-		tty_ldisc_put(new_ldisc);
-		goto enable;
-	}
 
-	if (test_bit(TTY_HUPPING, &tty->flags)) {
+	if (test_bit(TTY_HUPPING, &tty->flags) ||
+	    test_bit(TTY_HUPPED, &tty->flags)) {
 		/* We were raced by the hangup method. It will have stomped
 		   the ldisc data and closed the ldisc down */
-		clear_bit(TTY_LDISC_CHANGING, &tty->flags);
-		mutex_unlock(&tty->ldisc_mutex);
+		tty_ldisc_enable_pair(tty, o_tty);
 		tty_ldisc_put(new_ldisc);
 		tty_unlock(tty);
 		return -EIO;
 	}
 
-	/* Shutdown the current discipline. */
-	tty_ldisc_close(tty, o_ldisc);
+	/* Shutdown the old discipline. */
+	tty_ldisc_close(tty, old_ldisc);
 
 	/* Now set up the new line discipline. */
 	tty->ldisc = new_ldisc;
@@ -705,26 +564,24 @@ int tty_set_ldisc(struct tty_struct *tty, int ldisc)
 	if (retval < 0) {
 		/* Back to the old one or N_TTY if we can't */
 		tty_ldisc_put(new_ldisc);
-		tty_ldisc_restore(tty, o_ldisc);
+		tty_ldisc_restore(tty, old_ldisc);
 	}
 
-	/* At this point we hold a reference to the new ldisc and a
-	   a reference to the old ldisc. If we ended up flipping back
-	   to the existing ldisc we have two references to it */
-
-	if (tty->ldisc->ops->num != o_ldisc->ops->num && tty->ops->set_ldisc)
+	if (tty->ldisc->ops->num != old_ldisc->ops->num && tty->ops->set_ldisc)
 		tty->ops->set_ldisc(tty);
 
-	tty_ldisc_put(o_ldisc);
+	/* At this point we hold a reference to the new ldisc and a
+	   reference to the old ldisc, or we hold two references to
+	   the old ldisc (if it was restored as part of error cleanup
+	   above). In either case, releasing a single reference from
+	   the old ldisc is correct. */
+
+	tty_ldisc_put(old_ldisc);
 
-enable:
 	/*
 	 *	Allow ldisc referencing to occur again
 	 */
-
-	tty_ldisc_enable(tty);
-	if (o_tty)
-		tty_ldisc_enable(o_tty);
+	tty_ldisc_enable_pair(tty, o_tty);
 
 	/* Restart the work queue in case no characters kick it off. Safe if
 	   already running */
@@ -732,7 +589,6 @@ enable:
 	if (o_tty)
 		schedule_work(&o_tty->port->buf.work);
 
-	mutex_unlock(&tty->ldisc_mutex);
 	tty_unlock(tty);
 	return retval;
 }
@@ -746,11 +602,11 @@ enable:
 
 static void tty_reset_termios(struct tty_struct *tty)
 {
-	mutex_lock(&tty->termios_mutex);
+	down_write(&tty->termios_rwsem);
 	tty->termios = tty->driver->init_termios;
 	tty->termios.c_ispeed = tty_termios_input_baud_rate(&tty->termios);
 	tty->termios.c_ospeed = tty_termios_baud_rate(&tty->termios);
-	mutex_unlock(&tty->termios_mutex);
+	up_write(&tty->termios_rwsem);
 }
 
 
@@ -765,7 +621,7 @@ static void tty_reset_termios(struct tty_struct *tty)
 
 static int tty_ldisc_reinit(struct tty_struct *tty, int ldisc)
 {
-	struct tty_ldisc *ld = tty_ldisc_get(ldisc);
+	struct tty_ldisc *ld = tty_ldisc_get(tty, ldisc);
 
 	if (IS_ERR(ld))
 		return -1;
@@ -804,14 +660,8 @@ void tty_ldisc_hangup(struct tty_struct *tty)
 
 	tty_ldisc_debug(tty, "closing ldisc: %p\n", tty->ldisc);
 
-	/*
-	 * FIXME! What are the locking issues here? This may me overdoing
-	 * things... This question is especially important now that we've
-	 * removed the irqlock.
-	 */
 	ld = tty_ldisc_ref(tty);
 	if (ld != NULL) {
-		/* We may have no line discipline at this point */
 		if (ld->ops->flush_buffer)
 			ld->ops->flush_buffer(tty);
 		tty_driver_flush_buffer(tty);
@@ -822,21 +672,22 @@ void tty_ldisc_hangup(struct tty_struct *tty)
 			ld->ops->hangup(tty);
 		tty_ldisc_deref(ld);
 	}
-	/*
-	 * FIXME: Once we trust the LDISC code better we can wait here for
-	 * ldisc completion and fix the driver call race
-	 */
+
 	wake_up_interruptible_poll(&tty->write_wait, POLLOUT);
 	wake_up_interruptible_poll(&tty->read_wait, POLLIN);
+
+	tty_unlock(tty);
+
 	/*
 	 * Shutdown the current line discipline, and reset it to
 	 * N_TTY if need be.
 	 *
 	 * Avoid racing set_ldisc or tty_ldisc_release
 	 */
-	mutex_lock(&tty->ldisc_mutex);
+	tty_ldisc_lock_pair(tty, tty->link);
+	tty_lock(tty);
 
-	if (tty_ldisc_hangup_halt(tty)) {
+	if (tty->ldisc) {
 
 		/* At this point we have a halted ldisc; we want to close it and
 		   reopen a new ldisc. We could defer the reopen to the next
@@ -855,9 +706,8 @@ void tty_ldisc_hangup(struct tty_struct *tty)
 			BUG_ON(tty_ldisc_reinit(tty, N_TTY));
 			WARN_ON(tty_ldisc_open(tty, tty->ldisc));
 		}
-		tty_ldisc_enable(tty);
 	}
-	mutex_unlock(&tty->ldisc_mutex);
+	tty_ldisc_enable_pair(tty, tty->link);
 	if (reset)
 		tty_reset_termios(tty);
 
@@ -889,15 +739,12 @@ int tty_ldisc_setup(struct tty_struct *tty, struct tty_struct *o_tty)
 			tty_ldisc_close(tty, ld);
 			return retval;
 		}
-		tty_ldisc_enable(o_tty);
 	}
-	tty_ldisc_enable(tty);
 	return 0;
 }
 
 static void tty_ldisc_kill(struct tty_struct *tty)
 {
-	mutex_lock(&tty->ldisc_mutex);
 	/*
 	 * Now kill off the ldisc
 	 */
@@ -908,7 +755,6 @@ static void tty_ldisc_kill(struct tty_struct *tty)
 
 	/* Ensure the next open requests the N_TTY ldisc */
 	tty_set_termios_ldisc(tty, N_TTY);
-	mutex_unlock(&tty->ldisc_mutex);
 }
 
 /**
@@ -930,15 +776,16 @@ void tty_ldisc_release(struct tty_struct *tty, struct tty_struct *o_tty)
 
 	tty_ldisc_debug(tty, "closing ldisc: %p\n", tty->ldisc);
 
-	tty_ldisc_halt(tty, o_tty, MAX_SCHEDULE_TIMEOUT);
-
+	tty_ldisc_lock_pair(tty, o_tty);
 	tty_lock_pair(tty, o_tty);
-	/* This will need doing differently if we need to lock */
+
 	tty_ldisc_kill(tty);
 	if (o_tty)
 		tty_ldisc_kill(o_tty);
 
 	tty_unlock_pair(tty, o_tty);
+	tty_ldisc_unlock_pair(tty, o_tty);
+
 	/* And the memory resources remaining (buffers, termios) will be
 	   disposed of when the kref hits zero */
 
@@ -955,7 +802,7 @@ void tty_ldisc_release(struct tty_struct *tty, struct tty_struct *o_tty)
 
 void tty_ldisc_init(struct tty_struct *tty)
 {
-	struct tty_ldisc *ld = tty_ldisc_get(N_TTY);
+	struct tty_ldisc *ld = tty_ldisc_get(tty, N_TTY);
 	if (IS_ERR(ld))
 		panic("n_tty: init_tty");
 	tty->ldisc = ld;
diff --git a/drivers/tty/vt/keyboard.c b/drivers/tty/vt/keyboard.c
index a9af1b9ae16..d0e3a449770 100644
--- a/drivers/tty/vt/keyboard.c
+++ b/drivers/tty/vt/keyboard.c
@@ -132,12 +132,6 @@ static int shift_state = 0;
 static unsigned char ledstate = 0xff;			/* undefined */
 static unsigned char ledioctl;
 
-static struct ledptr {
-	unsigned int *addr;
-	unsigned int mask;
-	unsigned char valid:1;
-} ledptrs[3];
-
 /*
  * Notifier list for console keyboard events
  */
@@ -994,24 +988,11 @@ void setledstate(struct kbd_struct *kbd, unsigned int led)
 static inline unsigned char getleds(void)
 {
 	struct kbd_struct *kbd = kbd_table + fg_console;
-	unsigned char leds;
-	int i;
 
 	if (kbd->ledmode == LED_SHOW_IOCTL)
 		return ledioctl;
 
-	leds = kbd->ledflagstate;
-
-	if (kbd->ledmode == LED_SHOW_MEM) {
-		for (i = 0; i < 3; i++)
-			if (ledptrs[i].valid) {
-				if (*ledptrs[i].addr & ledptrs[i].mask)
-					leds |= (1 << i);
-				else
-					leds &= ~(1 << i);
-			}
-	}
-	return leds;
+	return kbd->ledflagstate;
 }
 
 static int kbd_update_leds_helper(struct input_handle *handle, void *data)
diff --git a/drivers/tty/vt/selection.c b/drivers/tty/vt/selection.c
index 60b7b692605..ea27804d87a 100644
--- a/drivers/tty/vt/selection.c
+++ b/drivers/tty/vt/selection.c
@@ -24,6 +24,7 @@
 #include <linux/selection.h>
 #include <linux/tiocl.h>
 #include <linux/console.h>
+#include <linux/tty_flip.h>
 
 /* Don't take this from <ctype.h>: 011-015 on the screen aren't spaces */
 #define isspace(c)	((c) == ' ')
@@ -346,8 +347,8 @@ int paste_selection(struct tty_struct *tty)
 	console_unlock();
 
 	ld = tty_ldisc_ref_wait(tty);
+	tty_buffer_lock_exclusive(&vc->port);
 
-	/* FIXME: this is completely unsafe */
 	add_wait_queue(&vc->paste_wait, &wait);
 	while (sel_buffer && sel_buffer_lth > pasted) {
 		set_current_state(TASK_INTERRUPTIBLE);
@@ -356,13 +357,14 @@ int paste_selection(struct tty_struct *tty)
 			continue;
 		}
 		count = sel_buffer_lth - pasted;
-		count = min(count, tty->receive_room);
-		ld->ops->receive_buf(tty, sel_buffer + pasted, NULL, count);
+		count = tty_ldisc_receive_buf(ld, sel_buffer + pasted, NULL,
+					      count);
 		pasted += count;
 	}
 	remove_wait_queue(&vc->paste_wait, &wait);
 	__set_current_state(TASK_RUNNING);
 
+	tty_buffer_unlock_exclusive(&vc->port);
 	tty_ldisc_deref(ld);
 	return 0;
 }
diff --git a/drivers/tty/vt/vt.c b/drivers/tty/vt/vt.c
index c677829baa8..9a8e8c5a0c7 100644
--- a/drivers/tty/vt/vt.c
+++ b/drivers/tty/vt/vt.c
@@ -828,7 +828,7 @@ static inline int resize_screen(struct vc_data *vc, int width, int height,
  *	If the caller passes a tty structure then update the termios winsize
  *	information and perform any necessary signal handling.
  *
- *	Caller must hold the console semaphore. Takes the termios mutex and
+ *	Caller must hold the console semaphore. Takes the termios rwsem and
  *	ctrl_lock of the tty IFF a tty is passed.
  */
 
@@ -972,7 +972,7 @@ int vc_resize(struct vc_data *vc, unsigned int cols, unsigned int rows)
  *	the actual work.
  *
  *	Takes the console sem and the called methods then take the tty
- *	termios_mutex and the tty ctrl_lock in that order.
+ *	termios_rwsem and the tty ctrl_lock in that order.
  */
 static int vt_resize(struct tty_struct *tty, struct winsize *ws)
 {
@@ -2809,8 +2809,10 @@ static void con_shutdown(struct tty_struct *tty)
 	console_unlock();
 }
 
+static int default_color           = 7; /* white */
 static int default_italic_color    = 2; // green (ASCII)
 static int default_underline_color = 3; // cyan (ASCII)
+module_param_named(color, default_color, int, S_IRUGO | S_IWUSR);
 module_param_named(italic, default_italic_color, int, S_IRUGO | S_IWUSR);
 module_param_named(underline, default_underline_color, int, S_IRUGO | S_IWUSR);
 
@@ -2832,7 +2834,7 @@ static void vc_init(struct vc_data *vc, unsigned int rows,
 		vc->vc_palette[k++] = default_grn[j] ;
 		vc->vc_palette[k++] = default_blu[j] ;
 	}
-	vc->vc_def_color       = 0x07;   /* white */
+	vc->vc_def_color       = default_color;
 	vc->vc_ulcolor         = default_underline_color;
 	vc->vc_itcolor         = default_italic_color;
 	vc->vc_halfcolor       = 0x08;   /* grey */