1 files changed, 445 insertions, 730 deletions

diff --git a/drivers/usb/serial/pl2303.c b/drivers/usb/serial/pl2303.c
index 9ec1a49e236..b3d5a35c0d4 100644
--- a/drivers/usb/serial/pl2303.c
+++ b/drivers/usb/serial/pl2303.c
@@ -12,12 +12,10 @@
  *
  * See Documentation/usb/usb-serial.txt for more information on using this
  * driver
- *
  */
 
 #include <linux/kernel.h>
 #include <linux/errno.h>
-#include <linux/init.h>
 #include <linux/slab.h>
 #include <linux/tty.h>
 #include <linux/tty_driver.h>
@@ -29,28 +27,14 @@
 #include <linux/uaccess.h>
 #include <linux/usb.h>
 #include <linux/usb/serial.h>
+#include <asm/unaligned.h>
 #include "pl2303.h"
 
-/*
- * Version Information
- */
-#define DRIVER_DESC "Prolific PL2303 USB to serial adaptor driver"
-
-static int debug;
-
-#define PL2303_CLOSING_WAIT	(30*HZ)
 
-#define PL2303_BUF_SIZE		1024
-#define PL2303_TMP_BUF_SIZE	1024
+#define PL2303_QUIRK_UART_STATE_IDX0		BIT(0)
+#define PL2303_QUIRK_LEGACY			BIT(1)
 
-struct pl2303_buf {
-	unsigned int	buf_size;
-	char		*buf_buf;
-	char		*buf_get;
-	char		*buf_put;
-};
-
-static struct usb_device_id id_table [] = {
+static const struct usb_device_id id_table[] = {
 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID) },
 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_RSAQ2) },
 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_DCU11) },
@@ -59,6 +43,8 @@ static struct usb_device_id id_table [] = {
 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_ALDIGA) },
 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_MMX) },
 	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_GPRS) },
+	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_HCR331) },
+	{ USB_DEVICE(PL2303_VENDOR_ID, PL2303_PRODUCT_ID_MOTOROLA) },
 	{ USB_DEVICE(IODATA_VENDOR_ID, IODATA_PRODUCT_ID) },
 	{ USB_DEVICE(IODATA_VENDOR_ID, IODATA_PRODUCT_ID_RSAQ5) },
 	{ USB_DEVICE(ATEN_VENDOR_ID, ATEN_PRODUCT_ID) },
@@ -75,9 +61,12 @@ static struct usb_device_id id_table [] = {
 	{ USB_DEVICE(SITECOM_VENDOR_ID, SITECOM_PRODUCT_ID) },
 	{ USB_DEVICE(ALCATEL_VENDOR_ID, ALCATEL_PRODUCT_ID) },
 	{ USB_DEVICE(SAMSUNG_VENDOR_ID, SAMSUNG_PRODUCT_ID) },
-	{ USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_SX1) },
-	{ USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_X65) },
-	{ USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_X75) },
+	{ USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_SX1),
+		.driver_info = PL2303_QUIRK_UART_STATE_IDX0 },
+	{ USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_X65),
+		.driver_info = PL2303_QUIRK_UART_STATE_IDX0 },
+	{ USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_X75),
+		.driver_info = PL2303_QUIRK_UART_STATE_IDX0 },
 	{ USB_DEVICE(SIEMENS_VENDOR_ID, SIEMENS_PRODUCT_ID_EF81) },
 	{ USB_DEVICE(BENQ_VENDOR_ID, BENQ_PRODUCT_ID_S81) }, /* Benq/Siemens S81 */
 	{ USB_DEVICE(SYNTECH_VENDOR_ID, SYNTECH_PRODUCT_ID) },
@@ -94,25 +83,20 @@ static struct usb_device_id id_table [] = {
 	{ USB_DEVICE(YCCABLE_VENDOR_ID, YCCABLE_PRODUCT_ID) },
 	{ USB_DEVICE(SUPERIAL_VENDOR_ID, SUPERIAL_PRODUCT_ID) },
 	{ USB_DEVICE(HP_VENDOR_ID, HP_LD220_PRODUCT_ID) },
+	{ USB_DEVICE(HP_VENDOR_ID, HP_LD960_PRODUCT_ID) },
+	{ USB_DEVICE(HP_VENDOR_ID, HP_LCM220_PRODUCT_ID) },
+	{ USB_DEVICE(HP_VENDOR_ID, HP_LCM960_PRODUCT_ID) },
 	{ USB_DEVICE(CRESSI_VENDOR_ID, CRESSI_EDY_PRODUCT_ID) },
+	{ USB_DEVICE(ZEAGLE_VENDOR_ID, ZEAGLE_N2ITION3_PRODUCT_ID) },
 	{ USB_DEVICE(SONY_VENDOR_ID, SONY_QN3USB_PRODUCT_ID) },
 	{ USB_DEVICE(SANWA_VENDOR_ID, SANWA_PRODUCT_ID) },
+	{ USB_DEVICE(ADLINK_VENDOR_ID, ADLINK_ND6530_PRODUCT_ID) },
+	{ USB_DEVICE(SMART_VENDOR_ID, SMART_PRODUCT_ID) },
 	{ }					/* Terminating entry */
 };
 
 MODULE_DEVICE_TABLE(usb, id_table);
 
-static struct usb_driver pl2303_driver = {
-	.name =		"pl2303",
-	.probe =	usb_serial_probe,
-	.disconnect =	usb_serial_disconnect,
-	.id_table =	id_table,
-	.suspend =      usb_serial_suspend,
-	.resume =       usb_serial_resume,
-	.no_dynamic_id = 	1,
-	.supports_autosuspend =	1,
-};
-
 #define SET_LINE_REQUEST_TYPE		0x21
 #define SET_LINE_REQUEST		0x20
 
@@ -135,7 +119,8 @@ static struct usb_driver pl2303_driver = {
 #define VENDOR_READ_REQUEST_TYPE	0xc0
 #define VENDOR_READ_REQUEST		0x01
 
-#define UART_STATE			0x08
+#define UART_STATE_INDEX		8
+#define UART_STATE_MSR_MASK		0x8b
 #define UART_STATE_TRANSIENT_MASK	0x74
 #define UART_DCD			0x01
 #define UART_DSR			0x02
@@ -148,564 +133,462 @@ static struct usb_driver pl2303_driver = {
 
 
 enum pl2303_type {
-	type_0,		/* don't know the difference between type 0 and */
-	type_1,		/* type 1, until someone from prolific tells us... */
-	HX,		/* HX version of the pl2303 chip */
+	TYPE_01,	/* Type 0 and 1 (difference unknown) */
+	TYPE_HX,	/* HX version of the pl2303 chip */
+	TYPE_COUNT
+};
+
+struct pl2303_type_data {
+	speed_t max_baud_rate;
+	unsigned long quirks;
+};
+
+struct pl2303_serial_private {
+	const struct pl2303_type_data *type;
+	unsigned long quirks;
 };
 
 struct pl2303_private {
 	spinlock_t lock;
-	struct pl2303_buf *buf;
-	int write_urb_in_use;
-	wait_queue_head_t delta_msr_wait;
 	u8 line_control;
 	u8 line_status;
-	enum pl2303_type type;
-};
 
-/*
- * pl2303_buf_alloc
- *
- * Allocate a circular buffer and all associated memory.
- */
-static struct pl2303_buf *pl2303_buf_alloc(unsigned int size)
-{
-	struct pl2303_buf *pb;
+	u8 line_settings[7];
+};
 
-	if (size == 0)
-		return NULL;
+static const struct pl2303_type_data pl2303_type_data[TYPE_COUNT] = {
+	[TYPE_01] = {
+		.max_baud_rate =	1228800,
+		.quirks =		PL2303_QUIRK_LEGACY,
+	},
+};
 
-	pb = kmalloc(sizeof(struct pl2303_buf), GFP_KERNEL);
-	if (pb == NULL)
-		return NULL;
+static int pl2303_vendor_read(struct usb_serial *serial, u16 value,
+							unsigned char buf[1])
+{
+	struct device *dev = &serial->interface->dev;
+	int res;
 
-	pb->buf_buf = kmalloc(size, GFP_KERNEL);
-	if (pb->buf_buf == NULL) {
-		kfree(pb);
-		return NULL;
+	res = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
+			VENDOR_READ_REQUEST, VENDOR_READ_REQUEST_TYPE,
+			value, 0, buf, 1, 100);
+	if (res != 1) {
+		dev_err(dev, "%s - failed to read [%04x]: %d\n", __func__,
+								value, res);
+		if (res >= 0)
+			res = -EIO;
+
+		return res;
 	}
 
-	pb->buf_size = size;
-	pb->buf_get = pb->buf_put = pb->buf_buf;
+	dev_dbg(dev, "%s - [%04x] = %02x\n", __func__, value, buf[0]);
 
-	return pb;
+	return 0;
 }
 
-/*
- * pl2303_buf_free
- *
- * Free the buffer and all associated memory.
- */
-static void pl2303_buf_free(struct pl2303_buf *pb)
+static int pl2303_vendor_write(struct usb_serial *serial, u16 value, u16 index)
 {
-	if (pb) {
-		kfree(pb->buf_buf);
-		kfree(pb);
-	}
-}
+	struct device *dev = &serial->interface->dev;
+	int res;
 
-/*
- * pl2303_buf_clear
- *
- * Clear out all data in the circular buffer.
- */
-static void pl2303_buf_clear(struct pl2303_buf *pb)
-{
-	if (pb != NULL)
-		pb->buf_get = pb->buf_put;
-		/* equivalent to a get of all data available */
-}
+	dev_dbg(dev, "%s - [%04x] = %02x\n", __func__, value, index);
 
-/*
- * pl2303_buf_data_avail
- *
- * Return the number of bytes of data available in the circular
- * buffer.
- */
-static unsigned int pl2303_buf_data_avail(struct pl2303_buf *pb)
-{
-	if (pb == NULL)
-		return 0;
+	res = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
+			VENDOR_WRITE_REQUEST, VENDOR_WRITE_REQUEST_TYPE,
+			value, index, NULL, 0, 100);
+	if (res) {
+		dev_err(dev, "%s - failed to write [%04x]: %d\n", __func__,
+								value, res);
+		return res;
+	}
 
-	return (pb->buf_size + pb->buf_put - pb->buf_get) % pb->buf_size;
+	return 0;
 }
 
-/*
- * pl2303_buf_space_avail
- *
- * Return the number of bytes of space available in the circular
- * buffer.
- */
-static unsigned int pl2303_buf_space_avail(struct pl2303_buf *pb)
+static int pl2303_probe(struct usb_serial *serial,
+					const struct usb_device_id *id)
 {
-	if (pb == NULL)
-		return 0;
+	usb_set_serial_data(serial, (void *)id->driver_info);
 
-	return (pb->buf_size + pb->buf_get - pb->buf_put - 1) % pb->buf_size;
+	return 0;
 }
 
-/*
- * pl2303_buf_put
- *
- * Copy data data from a user buffer and put it into the circular buffer.
- * Restrict to the amount of space available.
- *
- * Return the number of bytes copied.
- */
-static unsigned int pl2303_buf_put(struct pl2303_buf *pb, const char *buf,
-				   unsigned int count)
+static int pl2303_startup(struct usb_serial *serial)
 {
-	unsigned int len;
-
-	if (pb == NULL)
-		return 0;
-
-	len  = pl2303_buf_space_avail(pb);
-	if (count > len)
-		count = len;
+	struct pl2303_serial_private *spriv;
+	enum pl2303_type type = TYPE_01;
+	unsigned char *buf;
 
-	if (count == 0)
-		return 0;
+	spriv = kzalloc(sizeof(*spriv), GFP_KERNEL);
+	if (!spriv)
+		return -ENOMEM;
 
-	len = pb->buf_buf + pb->buf_size - pb->buf_put;
-	if (count > len) {
-		memcpy(pb->buf_put, buf, len);
-		memcpy(pb->buf_buf, buf+len, count - len);
-		pb->buf_put = pb->buf_buf + count - len;
-	} else {
-		memcpy(pb->buf_put, buf, count);
-		if (count < len)
-			pb->buf_put += count;
-		else /* count == len */
-			pb->buf_put = pb->buf_buf;
+	buf = kmalloc(1, GFP_KERNEL);
+	if (!buf) {
+		kfree(spriv);
+		return -ENOMEM;
 	}
 
-	return count;
-}
-
-/*
- * pl2303_buf_get
- *
- * Get data from the circular buffer and copy to the given buffer.
- * Restrict to the amount of data available.
- *
- * Return the number of bytes copied.
- */
-static unsigned int pl2303_buf_get(struct pl2303_buf *pb, char *buf,
-				   unsigned int count)
-{
-	unsigned int len;
-
-	if (pb == NULL)
-		return 0;
-
-	len = pl2303_buf_data_avail(pb);
-	if (count > len)
-		count = len;
-
-	if (count == 0)
-		return 0;
+	if (serial->dev->descriptor.bDeviceClass == 0x02)
+		type = TYPE_01;		/* type 0 */
+	else if (serial->dev->descriptor.bMaxPacketSize0 == 0x40)
+		type = TYPE_HX;
+	else if (serial->dev->descriptor.bDeviceClass == 0x00)
+		type = TYPE_01;		/* type 1 */
+	else if (serial->dev->descriptor.bDeviceClass == 0xFF)
+		type = TYPE_01;		/* type 1 */
+	dev_dbg(&serial->interface->dev, "device type: %d\n", type);
+
+	spriv->type = &pl2303_type_data[type];
+	spriv->quirks = (unsigned long)usb_get_serial_data(serial);
+	spriv->quirks |= spriv->type->quirks;
+
+	usb_set_serial_data(serial, spriv);
+
+	pl2303_vendor_read(serial, 0x8484, buf);
+	pl2303_vendor_write(serial, 0x0404, 0);
+	pl2303_vendor_read(serial, 0x8484, buf);
+	pl2303_vendor_read(serial, 0x8383, buf);
+	pl2303_vendor_read(serial, 0x8484, buf);
+	pl2303_vendor_write(serial, 0x0404, 1);
+	pl2303_vendor_read(serial, 0x8484, buf);
+	pl2303_vendor_read(serial, 0x8383, buf);
+	pl2303_vendor_write(serial, 0, 1);
+	pl2303_vendor_write(serial, 1, 0);
+	if (spriv->quirks & PL2303_QUIRK_LEGACY)
+		pl2303_vendor_write(serial, 2, 0x24);
+	else
+		pl2303_vendor_write(serial, 2, 0x44);
 
-	len = pb->buf_buf + pb->buf_size - pb->buf_get;
-	if (count > len) {
-		memcpy(buf, pb->buf_get, len);
-		memcpy(buf+len, pb->buf_buf, count - len);
-		pb->buf_get = pb->buf_buf + count - len;
-	} else {
-		memcpy(buf, pb->buf_get, count);
-		if (count < len)
-			pb->buf_get += count;
-		else /* count == len */
-			pb->buf_get = pb->buf_buf;
-	}
+	kfree(buf);
 
-	return count;
+	return 0;
 }
 
-static int pl2303_vendor_read(__u16 value, __u16 index,
-		struct usb_serial *serial, unsigned char *buf)
+static void pl2303_release(struct usb_serial *serial)
 {
-	int res = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
-			VENDOR_READ_REQUEST, VENDOR_READ_REQUEST_TYPE,
-			value, index, buf, 1, 100);
-	dbg("0x%x:0x%x:0x%x:0x%x  %d - %x", VENDOR_READ_REQUEST_TYPE,
-			VENDOR_READ_REQUEST, value, index, res, buf[0]);
-	return res;
-}
+	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
 
-static int pl2303_vendor_write(__u16 value, __u16 index,
-		struct usb_serial *serial)
-{
-	int res = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
-			VENDOR_WRITE_REQUEST, VENDOR_WRITE_REQUEST_TYPE,
-			value, index, NULL, 0, 100);
-	dbg("0x%x:0x%x:0x%x:0x%x  %d", VENDOR_WRITE_REQUEST_TYPE,
-			VENDOR_WRITE_REQUEST, value, index, res);
-	return res;
+	kfree(spriv);
 }
 
-static int pl2303_startup(struct usb_serial *serial)
+static int pl2303_port_probe(struct usb_serial_port *port)
 {
 	struct pl2303_private *priv;
-	enum pl2303_type type = type_0;
-	unsigned char *buf;
-	int i;
 
-	buf = kmalloc(10, GFP_KERNEL);
-	if (buf == NULL)
+	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+	if (!priv)
 		return -ENOMEM;
 
-	if (serial->dev->descriptor.bDeviceClass == 0x02)
-		type = type_0;
-	else if (serial->dev->descriptor.bMaxPacketSize0 == 0x40)
-		type = HX;
-	else if (serial->dev->descriptor.bDeviceClass == 0x00)
-		type = type_1;
-	else if (serial->dev->descriptor.bDeviceClass == 0xFF)
-		type = type_1;
-	dbg("device type: %d", type);
-
-	for (i = 0; i < serial->num_ports; ++i) {
-		priv = kzalloc(sizeof(struct pl2303_private), GFP_KERNEL);
-		if (!priv)
-			goto cleanup;
-		spin_lock_init(&priv->lock);
-		priv->buf = pl2303_buf_alloc(PL2303_BUF_SIZE);
-		if (priv->buf == NULL) {
-			kfree(priv);
-			goto cleanup;
-		}
-		init_waitqueue_head(&priv->delta_msr_wait);
-		priv->type = type;
-		usb_set_serial_port_data(serial->port[i], priv);
-	}
+	spin_lock_init(&priv->lock);
 
-	pl2303_vendor_read(0x8484, 0, serial, buf);
-	pl2303_vendor_write(0x0404, 0, serial);
-	pl2303_vendor_read(0x8484, 0, serial, buf);
-	pl2303_vendor_read(0x8383, 0, serial, buf);
-	pl2303_vendor_read(0x8484, 0, serial, buf);
-	pl2303_vendor_write(0x0404, 1, serial);
-	pl2303_vendor_read(0x8484, 0, serial, buf);
-	pl2303_vendor_read(0x8383, 0, serial, buf);
-	pl2303_vendor_write(0, 1, serial);
-	pl2303_vendor_write(1, 0, serial);
-	if (type == HX)
-		pl2303_vendor_write(2, 0x44, serial);
-	else
-		pl2303_vendor_write(2, 0x24, serial);
+	usb_set_serial_port_data(port, priv);
+
+	port->port.drain_delay = 256;
 
-	kfree(buf);
 	return 0;
+}
 
-cleanup:
-	kfree(buf);
-	for (--i; i >= 0; --i) {
-		priv = usb_get_serial_port_data(serial->port[i]);
-		pl2303_buf_free(priv->buf);
-		kfree(priv);
-		usb_set_serial_port_data(serial->port[i], NULL);
-	}
-	return -ENOMEM;
+static int pl2303_port_remove(struct usb_serial_port *port)
+{
+	struct pl2303_private *priv = usb_get_serial_port_data(port);
+
+	kfree(priv);
+
+	return 0;
 }
 
-static int set_control_lines(struct usb_device *dev, u8 value)
+static int pl2303_set_control_lines(struct usb_serial_port *port, u8 value)
 {
+	struct usb_device *dev = port->serial->dev;
 	int retval;
 
+	dev_dbg(&port->dev, "%s - %02x\n", __func__, value);
+
 	retval = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
 				 SET_CONTROL_REQUEST, SET_CONTROL_REQUEST_TYPE,
 				 value, 0, NULL, 0, 100);
-	dbg("%s - value = %d, retval = %d", __func__, value, retval);
+	if (retval)
+		dev_err(&port->dev, "%s - failed: %d\n", __func__, retval);
+
 	return retval;
 }
 
-static void pl2303_send(struct usb_serial_port *port)
+/*
+ * Returns the nearest supported baud rate that can be set directly without
+ * using divisors.
+ */
+static speed_t pl2303_get_supported_baud_rate(speed_t baud)
 {
-	int count, result;
-	struct pl2303_private *priv = usb_get_serial_port_data(port);
-	unsigned long flags;
+	static const speed_t baud_sup[] = {
+		75, 150, 300, 600, 1200, 1800, 2400, 3600, 4800, 7200, 9600,
+		14400, 19200, 28800, 38400, 57600, 115200, 230400, 460800,
+		614400, 921600, 1228800, 2457600, 3000000, 6000000
+	};
 
-	dbg("%s - port %d", __func__, port->number);
+	unsigned i;
 
-	spin_lock_irqsave(&priv->lock, flags);
-
-	if (priv->write_urb_in_use) {
-		spin_unlock_irqrestore(&priv->lock, flags);
-		return;
+	for (i = 0; i < ARRAY_SIZE(baud_sup); ++i) {
+		if (baud_sup[i] > baud)
+			break;
 	}
 
-	count = pl2303_buf_get(priv->buf, port->write_urb->transfer_buffer,
-			       port->bulk_out_size);
+	if (i == ARRAY_SIZE(baud_sup))
+		baud = baud_sup[i - 1];
+	else if (i > 0 && (baud_sup[i] - baud) > (baud - baud_sup[i - 1]))
+		baud = baud_sup[i - 1];
+	else
+		baud = baud_sup[i];
 
-	if (count == 0) {
-		spin_unlock_irqrestore(&priv->lock, flags);
-		return;
-	}
+	return baud;
+}
 
-	priv->write_urb_in_use = 1;
+/*
+ * NOTE: If unsupported baud rates are set directly, the PL2303 seems to
+ *       use 9600 baud.
+ */
+static speed_t pl2303_encode_baud_rate_direct(unsigned char buf[4],
+								speed_t baud)
+{
+	put_unaligned_le32(baud, buf);
 
-	spin_unlock_irqrestore(&priv->lock, flags);
+	return baud;
+}
 
-	usb_serial_debug_data(debug, &port->dev, __func__, count,
-			      port->write_urb->transfer_buffer);
+static speed_t pl2303_encode_baud_rate_divisor(unsigned char buf[4],
+								speed_t baud)
+{
+	unsigned int tmp;
 
-	port->write_urb->transfer_buffer_length = count;
-	port->write_urb->dev = port->serial->dev;
-	result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
-	if (result) {
-		dev_err(&port->dev, "%s - failed submitting write urb,"
-			" error %d\n", __func__, result);
-		priv->write_urb_in_use = 0;
-		/* TODO: reschedule pl2303_send */
+	/*
+	 * Apparently the formula is:
+	 * baudrate = 12M * 32 / (2^buf[1]) / buf[0]
+	 */
+	tmp = 12000000 * 32 / baud;
+	buf[3] = 0x80;
+	buf[2] = 0;
+	buf[1] = (tmp >= 256);
+	while (tmp >= 256) {
+		tmp >>= 2;
+		buf[1] <<= 1;
 	}
+	buf[0] = tmp;
 
-	usb_serial_port_softint(port);
+	return baud;
 }
 
-static int pl2303_write(struct tty_struct *tty, struct usb_serial_port *port,
-				const unsigned char *buf, int count)
+static void pl2303_encode_baud_rate(struct tty_struct *tty,
+					struct usb_serial_port *port,
+					u8 buf[4])
 {
-	struct pl2303_private *priv = usb_get_serial_port_data(port);
-	unsigned long flags;
-
-	dbg("%s - port %d, %d bytes", __func__, port->number, count);
+	struct usb_serial *serial = port->serial;
+	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
+	speed_t	baud_sup;
+	speed_t baud;
 
-	if (!count)
-		return count;
+	baud = tty_get_baud_rate(tty);
+	dev_dbg(&port->dev, "baud requested = %u\n", baud);
+	if (!baud)
+		return;
 
-	spin_lock_irqsave(&priv->lock, flags);
-	count = pl2303_buf_put(priv->buf, buf, count);
-	spin_unlock_irqrestore(&priv->lock, flags);
+	if (spriv->type->max_baud_rate)
+		baud = min_t(speed_t, baud, spriv->type->max_baud_rate);
+	/*
+	 * Set baud rate to nearest supported value.
+	 *
+	 * NOTE: Baud rate 500k can only be set using divisors.
+	 */
+	baud_sup = pl2303_get_supported_baud_rate(baud);
 
-	pl2303_send(port);
+	if (baud == 500000)
+		baud = pl2303_encode_baud_rate_divisor(buf, baud);
+	else
+		baud = pl2303_encode_baud_rate_direct(buf, baud_sup);
 
-	return count;
+	/* Save resulting baud rate */
+	tty_encode_baud_rate(tty, baud, baud);
+	dev_dbg(&port->dev, "baud set = %u\n", baud);
 }
 
-static int pl2303_write_room(struct tty_struct *tty)
+static int pl2303_get_line_request(struct usb_serial_port *port,
+							unsigned char buf[7])
 {
-	struct usb_serial_port *port = tty->driver_data;
-	struct pl2303_private *priv = usb_get_serial_port_data(port);
-	int room = 0;
-	unsigned long flags;
+	struct usb_device *udev = port->serial->dev;
+	int ret;
 
-	dbg("%s - port %d", __func__, port->number);
+	ret = usb_control_msg(udev, usb_rcvctrlpipe(udev, 0),
+				GET_LINE_REQUEST, GET_LINE_REQUEST_TYPE,
+				0, 0, buf, 7, 100);
+	if (ret != 7) {
+		dev_err(&port->dev, "%s - failed: %d\n", __func__, ret);
 
-	spin_lock_irqsave(&priv->lock, flags);
-	room = pl2303_buf_space_avail(priv->buf);
-	spin_unlock_irqrestore(&priv->lock, flags);
+		if (ret > 0)
+			ret = -EIO;
+
+		return ret;
+	}
+
+	dev_dbg(&port->dev, "%s - %7ph\n", __func__, buf);
 
-	dbg("%s - returns %d", __func__, room);
-	return room;
+	return 0;
 }
 
-static int pl2303_chars_in_buffer(struct tty_struct *tty)
+static int pl2303_set_line_request(struct usb_serial_port *port,
+							unsigned char buf[7])
 {
-	struct usb_serial_port *port = tty->driver_data;
-	struct pl2303_private *priv = usb_get_serial_port_data(port);
-	int chars = 0;
-	unsigned long flags;
+	struct usb_device *udev = port->serial->dev;
+	int ret;
 
-	dbg("%s - port %d", __func__, port->number);
+	ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
+				SET_LINE_REQUEST, SET_LINE_REQUEST_TYPE,
+				0, 0, buf, 7, 100);
+	if (ret != 7) {
+		dev_err(&port->dev, "%s - failed: %d\n", __func__, ret);
 
-	spin_lock_irqsave(&priv->lock, flags);
-	chars = pl2303_buf_data_avail(priv->buf);
-	spin_unlock_irqrestore(&priv->lock, flags);
+		if (ret > 0)
+			ret = -EIO;
+
+		return ret;
+	}
 
-	dbg("%s - returns %d", __func__, chars);
-	return chars;
+	dev_dbg(&port->dev, "%s - %7ph\n", __func__, buf);
+
+	return 0;
 }
 
 static void pl2303_set_termios(struct tty_struct *tty,
 		struct usb_serial_port *port, struct ktermios *old_termios)
 {
 	struct usb_serial *serial = port->serial;
+	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
 	struct pl2303_private *priv = usb_get_serial_port_data(port);
 	unsigned long flags;
-	unsigned int cflag;
 	unsigned char *buf;
-	int baud;
-	int i;
+	int ret;
 	u8 control;
-	const int baud_sup[] = { 75, 150, 300, 600, 1200, 1800, 2400, 3600,
-	                         4800, 7200, 9600, 14400, 19200, 28800, 38400,
-	                         57600, 115200, 230400, 460800, 614400,
-	                         921600, 1228800, 2457600, 3000000, 6000000 };
-	int baud_floor, baud_ceil;
-	int k;
-
-	dbg("%s -  port %d", __func__, port->number);
-
-	/* The PL2303 is reported to lose bytes if you change
-	   serial settings even to the same values as before. Thus
-	   we actually need to filter in this specific case */
 
-	if (!tty_termios_hw_change(tty->termios, old_termios))
+	if (old_termios && !tty_termios_hw_change(&tty->termios, old_termios))
 		return;
 
-	cflag = tty->termios->c_cflag;
-
 	buf = kzalloc(7, GFP_KERNEL);
 	if (!buf) {
-		dev_err(&port->dev, "%s - out of memory.\n", __func__);
 		/* Report back no change occurred */
-		*tty->termios = *old_termios;
+		if (old_termios)
+			tty->termios = *old_termios;
 		return;
 	}
 
-	i = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
-			    GET_LINE_REQUEST, GET_LINE_REQUEST_TYPE,
-			    0, 0, buf, 7, 100);
-	dbg("0xa1:0x21:0:0  %d - %x %x %x %x %x %x %x", i,
-	    buf[0], buf[1], buf[2], buf[3], buf[4], buf[5], buf[6]);
+	pl2303_get_line_request(port, buf);
 
-	if (cflag & CSIZE) {
-		switch (cflag & CSIZE) {
-		case CS5:
-			buf[6] = 5;
-			break;
-		case CS6:
-			buf[6] = 6;
-			break;
-		case CS7:
-			buf[6] = 7;
-			break;
-		default:
-		case CS8:
-			buf[6] = 8;
-			break;
-		}
-		dbg("%s - data bits = %d", __func__, buf[6]);
+	switch (C_CSIZE(tty)) {
+	case CS5:
+		buf[6] = 5;
+		break;
+	case CS6:
+		buf[6] = 6;
+		break;
+	case CS7:
+		buf[6] = 7;
+		break;
+	default:
+	case CS8:
+		buf[6] = 8;
 	}
+	dev_dbg(&port->dev, "data bits = %d\n", buf[6]);
 
 	/* For reference buf[0]:buf[3] baud rate value */
-	/* NOTE: Only the values defined in baud_sup are supported !
-	 *       => if unsupported values are set, the PL2303 seems to use
-	 *          9600 baud (at least my PL2303X always does)
-	 */
-	baud = tty_get_baud_rate(tty);
-	dbg("%s - baud requested = %d", __func__, baud);
-	if (baud) {
-		/* Set baudrate to nearest supported value */
-		for (k=0; k<ARRAY_SIZE(baud_sup); k++) {
-			if (baud_sup[k] / baud) {
-				baud_ceil = baud_sup[k];
-				if (k==0) {
-					baud = baud_ceil;
-				} else {
-					baud_floor = baud_sup[k-1];
-					if ((baud_ceil % baud)
-					    > (baud % baud_floor))
-						baud = baud_floor;
-					else
-						baud = baud_ceil;
-				}
-				break;
-			}
-		}
-		if (baud > 1228800) {
-			/* type_0, type_1 only support up to 1228800 baud */
-			if (priv->type != HX)
-				baud = 1228800;
-			else if (baud > 6000000)
-				baud = 6000000;
-		}
-		dbg("%s - baud set = %d", __func__, baud);
-		buf[0] = baud & 0xff;
-		buf[1] = (baud >> 8) & 0xff;
-		buf[2] = (baud >> 16) & 0xff;
-		buf[3] = (baud >> 24) & 0xff;
-	}
+	pl2303_encode_baud_rate(tty, port, &buf[0]);
 
 	/* For reference buf[4]=0 is 1 stop bits */
 	/* For reference buf[4]=1 is 1.5 stop bits */
 	/* For reference buf[4]=2 is 2 stop bits */
-	if (cflag & CSTOPB) {
-		/* NOTE: Comply with "real" UARTs / RS232:
+	if (C_CSTOPB(tty)) {
+		/*
+		 * NOTE: Comply with "real" UARTs / RS232:
 		 *       use 1.5 instead of 2 stop bits with 5 data bits
 		 */
-		if ((cflag & CSIZE) == CS5) {
+		if (C_CSIZE(tty) == CS5) {
 			buf[4] = 1;
-			dbg("%s - stop bits = 1.5", __func__);
+			dev_dbg(&port->dev, "stop bits = 1.5\n");
 		} else {
 			buf[4] = 2;
-			dbg("%s - stop bits = 2", __func__);
+			dev_dbg(&port->dev, "stop bits = 2\n");
 		}
 	} else {
 		buf[4] = 0;
-		dbg("%s - stop bits = 1", __func__);
+		dev_dbg(&port->dev, "stop bits = 1\n");
 	}
 
-	if (cflag & PARENB) {
+	if (C_PARENB(tty)) {
 		/* For reference buf[5]=0 is none parity */
 		/* For reference buf[5]=1 is odd parity */
 		/* For reference buf[5]=2 is even parity */
 		/* For reference buf[5]=3 is mark parity */
 		/* For reference buf[5]=4 is space parity */
-		if (cflag & PARODD) {
-			if (cflag & CMSPAR) {
+		if (C_PARODD(tty)) {
+			if (C_CMSPAR(tty)) {
 				buf[5] = 3;
-				dbg("%s - parity = mark", __func__);
+				dev_dbg(&port->dev, "parity = mark\n");
 			} else {
 				buf[5] = 1;
-				dbg("%s - parity = odd", __func__);
+				dev_dbg(&port->dev, "parity = odd\n");
 			}
 		} else {
-			if (cflag & CMSPAR) {
+			if (C_CMSPAR(tty)) {
 				buf[5] = 4;
-				dbg("%s - parity = space", __func__);
+				dev_dbg(&port->dev, "parity = space\n");
 			} else {
 				buf[5] = 2;
-				dbg("%s - parity = even", __func__);
+				dev_dbg(&port->dev, "parity = even\n");
 			}
 		}
 	} else {
 		buf[5] = 0;
-		dbg("%s - parity = none", __func__);
+		dev_dbg(&port->dev, "parity = none\n");
 	}
 
-	i = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
-			    SET_LINE_REQUEST, SET_LINE_REQUEST_TYPE,
-			    0, 0, buf, 7, 100);
-	dbg("0x21:0x20:0:0  %d", i);
+	/*
+	 * Some PL2303 are known to lose bytes if you change serial settings
+	 * even to the same values as before. Thus we actually need to filter
+	 * in this specific case.
+	 *
+	 * Note that the tty_termios_hw_change check above is not sufficient
+	 * as a previously requested baud rate may differ from the one
+	 * actually used (and stored in old_termios).
+	 *
+	 * NOTE: No additional locking needed for line_settings as it is
+	 *       only used in set_termios, which is serialised against itself.
+	 */
+	if (!old_termios || memcmp(buf, priv->line_settings, 7)) {
+		ret = pl2303_set_line_request(port, buf);
+		if (!ret)
+			memcpy(priv->line_settings, buf, 7);
+	}
 
 	/* change control lines if we are switching to or from B0 */
 	spin_lock_irqsave(&priv->lock, flags);
 	control = priv->line_control;
-	if ((cflag & CBAUD) == B0)
+	if (C_BAUD(tty) == B0)
 		priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
-	else
+	else if (old_termios && (old_termios->c_cflag & CBAUD) == B0)
 		priv->line_control |= (CONTROL_DTR | CONTROL_RTS);
 	if (control != priv->line_control) {
 		control = priv->line_control;
 		spin_unlock_irqrestore(&priv->lock, flags);
-		set_control_lines(serial->dev, control);
+		pl2303_set_control_lines(port, control);
 	} else {
 		spin_unlock_irqrestore(&priv->lock, flags);
 	}
 
-	buf[0] = buf[1] = buf[2] = buf[3] = buf[4] = buf[5] = buf[6] = 0;
-
-	i = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
-			    GET_LINE_REQUEST, GET_LINE_REQUEST_TYPE,
-			    0, 0, buf, 7, 100);
-	dbg("0xa1:0x21:0:0  %d - %x %x %x %x %x %x %x", i,
-	     buf[0], buf[1], buf[2], buf[3], buf[4], buf[5], buf[6]);
-
-	if (cflag & CRTSCTS) {
-		if (priv->type == HX)
-			pl2303_vendor_write(0x0, 0x61, serial);
+	if (C_CRTSCTS(tty)) {
+		if (spriv->quirks & PL2303_QUIRK_LEGACY)
+			pl2303_vendor_write(serial, 0x0, 0x41);
 		else
-			pl2303_vendor_write(0x0, 0x41, serial);
+			pl2303_vendor_write(serial, 0x0, 0x61);
 	} else {
-		pl2303_vendor_write(0x0, 0x0, serial);
+		pl2303_vendor_write(serial, 0x0, 0x0);
 	}
 
-	/* Save resulting baud rate */
-	if (baud)
-		tty_encode_baud_rate(tty, baud, baud);
-
 	kfree(buf);
 }
 
@@ -716,91 +599,65 @@ static void pl2303_dtr_rts(struct usb_serial_port *port, int on)
 	u8 control;
 
 	spin_lock_irqsave(&priv->lock, flags);
-	/* Change DTR and RTS */
 	if (on)
 		priv->line_control |= (CONTROL_DTR | CONTROL_RTS);
 	else
 		priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
 	control = priv->line_control;
 	spin_unlock_irqrestore(&priv->lock, flags);
-	set_control_lines(port->serial->dev, control);
+
+	pl2303_set_control_lines(port, control);
 }
 
 static void pl2303_close(struct usb_serial_port *port)
 {
-	struct pl2303_private *priv = usb_get_serial_port_data(port);
-	unsigned long flags;
-
-	dbg("%s - port %d", __func__, port->number);
-
-	spin_lock_irqsave(&priv->lock, flags);
-	/* clear out any remaining data in the buffer */
-	pl2303_buf_clear(priv->buf);
-	spin_unlock_irqrestore(&priv->lock, flags);
-
-	/* shutdown our urbs */
-	dbg("%s - shutting down urbs", __func__);
-	usb_kill_urb(port->write_urb);
-	usb_kill_urb(port->read_urb);
+	usb_serial_generic_close(port);
 	usb_kill_urb(port->interrupt_in_urb);
-
 }
 
 static int pl2303_open(struct tty_struct *tty, struct usb_serial_port *port)
 {
-	struct ktermios tmp_termios;
 	struct usb_serial *serial = port->serial;
-	struct pl2303_private *priv = usb_get_serial_port_data(port);
+	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
 	int result;
 
-	dbg("%s -  port %d", __func__, port->number);
-
-	if (priv->type != HX) {
+	if (spriv->quirks & PL2303_QUIRK_LEGACY) {
 		usb_clear_halt(serial->dev, port->write_urb->pipe);
 		usb_clear_halt(serial->dev, port->read_urb->pipe);
 	} else {
 		/* reset upstream data pipes */
-		pl2303_vendor_write(8, 0, serial);
-		pl2303_vendor_write(9, 0, serial);
+		pl2303_vendor_write(serial, 8, 0);
+		pl2303_vendor_write(serial, 9, 0);
 	}
 
 	/* Setup termios */
 	if (tty)
-		pl2303_set_termios(tty, port, &tmp_termios);
+		pl2303_set_termios(tty, port, NULL);
 
-	dbg("%s - submitting read urb", __func__);
-	port->read_urb->dev = serial->dev;
-	result = usb_submit_urb(port->read_urb, GFP_KERNEL);
+	result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
 	if (result) {
-		dev_err(&port->dev, "%s - failed submitting read urb,"
-			" error %d\n", __func__, result);
-		pl2303_close(port);
-		return -EPROTO;
+		dev_err(&port->dev, "failed to submit interrupt urb: %d\n",
+			result);
+		return result;
 	}
 
-	dbg("%s - submitting interrupt urb", __func__);
-	port->interrupt_in_urb->dev = serial->dev;
-	result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
+	result = usb_serial_generic_open(tty, port);
 	if (result) {
-		dev_err(&port->dev, "%s - failed submitting interrupt urb,"
-			" error %d\n", __func__, result);
-		pl2303_close(port);
-		return -EPROTO;
+		usb_kill_urb(port->interrupt_in_urb);
+		return result;
 	}
-	port->port.drain_delay = 256;
+
 	return 0;
 }
 
-static int pl2303_tiocmset(struct tty_struct *tty, struct file *file,
+static int pl2303_tiocmset(struct tty_struct *tty,
 			   unsigned int set, unsigned int clear)
 {
 	struct usb_serial_port *port = tty->driver_data;
 	struct pl2303_private *priv = usb_get_serial_port_data(port);
 	unsigned long flags;
 	u8 control;
-
-	if (!usb_get_intfdata(port->serial->interface))
-		return -ENODEV;
+	int ret;
 
 	spin_lock_irqsave(&priv->lock, flags);
 	if (set & TIOCM_RTS)
@@ -814,10 +671,14 @@ static int pl2303_tiocmset(struct tty_struct *tty, struct file *file,
 	control = priv->line_control;
 	spin_unlock_irqrestore(&priv->lock, flags);
 
-	return set_control_lines(port->serial->dev, control);
+	ret = pl2303_set_control_lines(port, control);
+	if (ret)
+		return usb_translate_errors(ret);
+
+	return 0;
 }
 
-static int pl2303_tiocmget(struct tty_struct *tty, struct file *file)
+static int pl2303_tiocmget(struct tty_struct *tty)
 {
 	struct usb_serial_port *port = tty->driver_data;
 	struct pl2303_private *priv = usb_get_serial_port_data(port);
@@ -826,11 +687,6 @@ static int pl2303_tiocmget(struct tty_struct *tty, struct file *file)
 	unsigned int status;
 	unsigned int result;
 
-	dbg("%s (%d)", __func__, port->number);
-
-	if (!usb_get_intfdata(port->serial->interface))
-		return -ENODEV;
-
 	spin_lock_irqsave(&priv->lock, flags);
 	mcr = priv->line_control;
 	status = priv->line_status;
@@ -843,7 +699,7 @@ static int pl2303_tiocmget(struct tty_struct *tty, struct file *file)
 		  | ((status & UART_RING)	? TIOCM_RI  : 0)
 		  | ((status & UART_DCD)	? TIOCM_CD  : 0);
 
-	dbg("%s - result = %x", __func__, result);
+	dev_dbg(&port->dev, "%s - result = %x\n", __func__, result);
 
 	return result;
 }
@@ -851,61 +707,35 @@ static int pl2303_tiocmget(struct tty_struct *tty, struct file *file)
 static int pl2303_carrier_raised(struct usb_serial_port *port)
 {
 	struct pl2303_private *priv = usb_get_serial_port_data(port);
+
 	if (priv->line_status & UART_DCD)
 		return 1;
-	return 0;
-}
-
-static int wait_modem_info(struct usb_serial_port *port, unsigned int arg)
-{
-	struct pl2303_private *priv = usb_get_serial_port_data(port);
-	unsigned long flags;
-	unsigned int prevstatus;
-	unsigned int status;
-	unsigned int changed;
 
-	spin_lock_irqsave(&priv->lock, flags);
-	prevstatus = priv->line_status;
-	spin_unlock_irqrestore(&priv->lock, flags);
-
-	while (1) {
-		interruptible_sleep_on(&priv->delta_msr_wait);
-		/* see if a signal did it */
-		if (signal_pending(current))
-			return -ERESTARTSYS;
-
-		spin_lock_irqsave(&priv->lock, flags);
-		status = priv->line_status;
-		spin_unlock_irqrestore(&priv->lock, flags);
-
-		changed = prevstatus ^ status;
-
-		if (((arg & TIOCM_RNG) && (changed & UART_RING)) ||
-		    ((arg & TIOCM_DSR) && (changed & UART_DSR)) ||
-		    ((arg & TIOCM_CD)  && (changed & UART_DCD)) ||
-		    ((arg & TIOCM_CTS) && (changed & UART_CTS))) {
-			return 0;
-		}
-		prevstatus = status;
-	}
-	/* NOTREACHED */
 	return 0;
 }
 
-static int pl2303_ioctl(struct tty_struct *tty, struct file *file,
+static int pl2303_ioctl(struct tty_struct *tty,
 			unsigned int cmd, unsigned long arg)
 {
+	struct serial_struct ser;
 	struct usb_serial_port *port = tty->driver_data;
-	dbg("%s (%d) cmd = 0x%04x", __func__, port->number, cmd);
 
 	switch (cmd) {
-	case TIOCMIWAIT:
-		dbg("%s (%d) TIOCMIWAIT", __func__,  port->number);
-		return wait_modem_info(port, arg);
+	case TIOCGSERIAL:
+		memset(&ser, 0, sizeof ser);
+		ser.type = PORT_16654;
+		ser.line = port->minor;
+		ser.port = port->port_number;
+		ser.baud_base = 460800;
+
+		if (copy_to_user((void __user *)arg, &ser, sizeof ser))
+			return -EFAULT;
+
+		return 0;
 	default:
-		dbg("%s not supported = 0x%04x", __func__, cmd);
 		break;
 	}
+
 	return -ENOIOCTLCMD;
 }
 
@@ -916,73 +746,70 @@ static void pl2303_break_ctl(struct tty_struct *tty, int break_state)
 	u16 state;
 	int result;
 
-	dbg("%s - port %d", __func__, port->number);
-
 	if (break_state == 0)
 		state = BREAK_OFF;
 	else
 		state = BREAK_ON;
-	dbg("%s - turning break %s", __func__,
+
+	dev_dbg(&port->dev, "%s - turning break %s\n", __func__,
 			state == BREAK_OFF ? "off" : "on");
 
 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
 				 BREAK_REQUEST, BREAK_REQUEST_TYPE, state,
 				 0, NULL, 0, 100);
 	if (result)
-		dbg("%s - error sending break = %d", __func__, result);
-}
-
-static void pl2303_release(struct usb_serial *serial)
-{
-	int i;
-	struct pl2303_private *priv;
-
-	dbg("%s", __func__);
-
-	for (i = 0; i < serial->num_ports; ++i) {
-		priv = usb_get_serial_port_data(serial->port[i]);
-		if (priv) {
-			pl2303_buf_free(priv->buf);
-			kfree(priv);
-		}
-	}
+		dev_err(&port->dev, "error sending break = %d\n", result);
 }
 
 static void pl2303_update_line_status(struct usb_serial_port *port,
 				      unsigned char *data,
 				      unsigned int actual_length)
 {
-
+	struct usb_serial *serial = port->serial;
+	struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
 	struct pl2303_private *priv = usb_get_serial_port_data(port);
+	struct tty_struct *tty;
 	unsigned long flags;
-	u8 status_idx = UART_STATE;
-	u8 length = UART_STATE + 1;
-	u16 idv, idp;
-
-	idv = le16_to_cpu(port->serial->dev->descriptor.idVendor);
-	idp = le16_to_cpu(port->serial->dev->descriptor.idProduct);
-
-
-	if (idv == SIEMENS_VENDOR_ID) {
-		if (idp == SIEMENS_PRODUCT_ID_X65 ||
-		    idp == SIEMENS_PRODUCT_ID_SX1 ||
-		    idp == SIEMENS_PRODUCT_ID_X75) {
+	unsigned int status_idx = UART_STATE_INDEX;
+	u8 status;
+	u8 delta;
 
-			length = 1;
-			status_idx = 0;
-		}
-	}
+	if (spriv->quirks & PL2303_QUIRK_UART_STATE_IDX0)
+		status_idx = 0;
 
-	if (actual_length < length)
+	if (actual_length < status_idx + 1)
 		return;
 
+	status = data[status_idx];
+
 	/* Save off the uart status for others to look at */
 	spin_lock_irqsave(&priv->lock, flags);
-	priv->line_status = data[status_idx];
+	delta = priv->line_status ^ status;
+	priv->line_status = status;
 	spin_unlock_irqrestore(&priv->lock, flags);
-	if (priv->line_status & UART_BREAK_ERROR)
+
+	if (status & UART_BREAK_ERROR)
 		usb_serial_handle_break(port);
-	wake_up_interruptible(&priv->delta_msr_wait);
+
+	if (delta & UART_STATE_MSR_MASK) {
+		if (delta & UART_CTS)
+			port->icount.cts++;
+		if (delta & UART_DSR)
+			port->icount.dsr++;
+		if (delta & UART_RING)
+			port->icount.rng++;
+		if (delta & UART_DCD) {
+			port->icount.dcd++;
+			tty = tty_port_tty_get(&port->port);
+			if (tty) {
+				usb_serial_handle_dcd_change(port, tty,
+							status & UART_DCD);
+				tty_kref_put(tty);
+			}
+		}
+
+		wake_up_interruptible(&port->port.delta_msr_wait);
+	}
 }
 
 static void pl2303_read_int_callback(struct urb *urb)
@@ -993,8 +820,6 @@ static void pl2303_read_int_callback(struct urb *urb)
 	int status = urb->status;
 	int retval;
 
-	dbg("%s (%d)", __func__, port->number);
-
 	switch (status) {
 	case 0:
 		/* success */
@@ -1003,222 +828,112 @@ static void pl2303_read_int_callback(struct urb *urb)
 	case -ENOENT:
 	case -ESHUTDOWN:
 		/* this urb is terminated, clean up */
-		dbg("%s - urb shutting down with status: %d", __func__,
-		    status);
+		dev_dbg(&port->dev, "%s - urb shutting down with status: %d\n",
+			__func__, status);
 		return;
 	default:
-		dbg("%s - nonzero urb status received: %d", __func__,
-		    status);
+		dev_dbg(&port->dev, "%s - nonzero urb status received: %d\n",
+			__func__, status);
 		goto exit;
 	}
 
-	usb_serial_debug_data(debug, &port->dev, __func__,
+	usb_serial_debug_data(&port->dev, __func__,
 			      urb->actual_length, urb->transfer_buffer);
 
 	pl2303_update_line_status(port, data, actual_length);
 
 exit:
 	retval = usb_submit_urb(urb, GFP_ATOMIC);
-	if (retval)
-		dev_err(&urb->dev->dev,
+	if (retval) {
+		dev_err(&port->dev,
 			"%s - usb_submit_urb failed with result %d\n",
 			__func__, retval);
-}
-
-static void pl2303_push_data(struct tty_struct *tty,
-		struct usb_serial_port *port, struct urb *urb,
-		u8 line_status)
-{
-	unsigned char *data = urb->transfer_buffer;
-	/* get tty_flag from status */
-	char tty_flag = TTY_NORMAL;
-	/* break takes precedence over parity, */
-	/* which takes precedence over framing errors */
-	if (line_status & UART_BREAK_ERROR)
-		tty_flag = TTY_BREAK;
-	else if (line_status & UART_PARITY_ERROR)
-		tty_flag = TTY_PARITY;
-	else if (line_status & UART_FRAME_ERROR)
-		tty_flag = TTY_FRAME;
-	dbg("%s - tty_flag = %d", __func__, tty_flag);
-
-	tty_buffer_request_room(tty, urb->actual_length + 1);
-	/* overrun is special, not associated with a char */
-	if (line_status & UART_OVERRUN_ERROR)
-		tty_insert_flip_char(tty, 0, TTY_OVERRUN);
-
-	if (tty_flag == TTY_NORMAL && !(port->console && port->sysrq))
-		tty_insert_flip_string(tty, data, urb->actual_length);
-	else {
-		int i;
-		for (i = 0; i < urb->actual_length; ++i)
-			if (!usb_serial_handle_sysrq_char(tty, port, data[i]))
-				tty_insert_flip_char(tty, data[i], tty_flag);
 	}
-	tty_flip_buffer_push(tty);
 }
 
-static void pl2303_read_bulk_callback(struct urb *urb)
+static void pl2303_process_read_urb(struct urb *urb)
 {
-	struct usb_serial_port *port =  urb->context;
+	struct usb_serial_port *port = urb->context;
 	struct pl2303_private *priv = usb_get_serial_port_data(port);
-	struct tty_struct *tty;
+	unsigned char *data = urb->transfer_buffer;
+	char tty_flag = TTY_NORMAL;
 	unsigned long flags;
-	int result;
-	int status = urb->status;
 	u8 line_status;
+	int i;
 
-	dbg("%s - port %d", __func__, port->number);
-
-	if (status) {
-		dbg("%s - urb status = %d", __func__, status);
-		if (!port->port.count) {
-			dbg("%s - port is closed, exiting.", __func__);
-			return;
-		}
-		if (status == -EPROTO) {
-			/* PL2303 mysteriously fails with -EPROTO reschedule
-			 * the read */
-			dbg("%s - caught -EPROTO, resubmitting the urb",
-			    __func__);
-			urb->dev = port->serial->dev;
-			result = usb_submit_urb(urb, GFP_ATOMIC);
-			if (result)
-				dev_err(&urb->dev->dev, "%s - failed"
-					" resubmitting read urb, error %d\n",
-					__func__, result);
-			return;
-		}
-		dbg("%s - unable to handle the error, exiting.", __func__);
-		return;
-	}
-
-	usb_serial_debug_data(debug, &port->dev, __func__,
-			      urb->actual_length, urb->transfer_buffer);
-
+	/* update line status */
 	spin_lock_irqsave(&priv->lock, flags);
 	line_status = priv->line_status;
 	priv->line_status &= ~UART_STATE_TRANSIENT_MASK;
 	spin_unlock_irqrestore(&priv->lock, flags);
-	wake_up_interruptible(&priv->delta_msr_wait);
 
-	tty = tty_port_tty_get(&port->port);
-	if (tty && urb->actual_length) {
-		pl2303_push_data(tty, port, urb, line_status);
-	}
-	tty_kref_put(tty);
-	/* Schedule the next read _if_ we are still open */
-	if (port->port.count) {
-		urb->dev = port->serial->dev;
-		result = usb_submit_urb(urb, GFP_ATOMIC);
-		if (result)
-			dev_err(&urb->dev->dev, "%s - failed resubmitting"
-				" read urb, error %d\n", __func__, result);
-	}
-
-	return;
-}
+	if (!urb->actual_length)
+		return;
 
-static void pl2303_write_bulk_callback(struct urb *urb)
-{
-	struct usb_serial_port *port =  urb->context;
-	struct pl2303_private *priv = usb_get_serial_port_data(port);
-	int result;
-	int status = urb->status;
+	/*
+	 * Break takes precedence over parity, which takes precedence over
+	 * framing errors.
+	 */
+	if (line_status & UART_BREAK_ERROR)
+		tty_flag = TTY_BREAK;
+	else if (line_status & UART_PARITY_ERROR)
+		tty_flag = TTY_PARITY;
+	else if (line_status & UART_FRAME_ERROR)
+		tty_flag = TTY_FRAME;
 
-	dbg("%s - port %d", __func__, port->number);
+	if (tty_flag != TTY_NORMAL)
+		dev_dbg(&port->dev, "%s - tty_flag = %d\n", __func__,
+								tty_flag);
+	/* overrun is special, not associated with a char */
+	if (line_status & UART_OVERRUN_ERROR)
+		tty_insert_flip_char(&port->port, 0, TTY_OVERRUN);
 
-	switch (status) {
-	case 0:
-		/* success */
-		break;
-	case -ECONNRESET:
-	case -ENOENT:
-	case -ESHUTDOWN:
-		/* this urb is terminated, clean up */
-		dbg("%s - urb shutting down with status: %d", __func__,
-		    status);
-		priv->write_urb_in_use = 0;
-		return;
-	default:
-		/* error in the urb, so we have to resubmit it */
-		dbg("%s - Overflow in write", __func__);
-		dbg("%s - nonzero write bulk status received: %d", __func__,
-		    status);
-		port->write_urb->transfer_buffer_length = 1;
-		port->write_urb->dev = port->serial->dev;
-		result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
-		if (result)
-			dev_err(&urb->dev->dev, "%s - failed resubmitting write"
-				" urb, error %d\n", __func__, result);
-		else
-			return;
+	if (port->port.console && port->sysrq) {
+		for (i = 0; i < urb->actual_length; ++i)
+			if (!usb_serial_handle_sysrq_char(port, data[i]))
+				tty_insert_flip_char(&port->port, data[i],
+						tty_flag);
+	} else {
+		tty_insert_flip_string_fixed_flag(&port->port, data, tty_flag,
+							urb->actual_length);
 	}
 
-	priv->write_urb_in_use = 0;
-
-	/* send any buffered data */
-	pl2303_send(port);
+	tty_flip_buffer_push(&port->port);
 }
 
-/* All of the device info needed for the PL2303 SIO serial converter */
 static struct usb_serial_driver pl2303_device = {
 	.driver = {
 		.owner =	THIS_MODULE,
 		.name =		"pl2303",
 	},
 	.id_table =		id_table,
-	.usb_driver = 		&pl2303_driver,
 	.num_ports =		1,
+	.bulk_in_size =		256,
+	.bulk_out_size =	256,
 	.open =			pl2303_open,
 	.close =		pl2303_close,
-	.dtr_rts = 		pl2303_dtr_rts,
+	.dtr_rts =		pl2303_dtr_rts,
 	.carrier_raised =	pl2303_carrier_raised,
-	.write =		pl2303_write,
 	.ioctl =		pl2303_ioctl,
 	.break_ctl =		pl2303_break_ctl,
 	.set_termios =		pl2303_set_termios,
 	.tiocmget =		pl2303_tiocmget,
 	.tiocmset =		pl2303_tiocmset,
-	.read_bulk_callback =	pl2303_read_bulk_callback,
+	.tiocmiwait =		usb_serial_generic_tiocmiwait,
+	.process_read_urb =	pl2303_process_read_urb,
 	.read_int_callback =	pl2303_read_int_callback,
-	.write_bulk_callback =	pl2303_write_bulk_callback,
-	.write_room =		pl2303_write_room,
-	.chars_in_buffer =	pl2303_chars_in_buffer,
+	.probe =		pl2303_probe,
 	.attach =		pl2303_startup,
 	.release =		pl2303_release,
+	.port_probe =		pl2303_port_probe,
+	.port_remove =		pl2303_port_remove,
 };
 
-static int __init pl2303_init(void)
-{
-	int retval;
-
-	retval = usb_serial_register(&pl2303_device);
-	if (retval)
-		goto failed_usb_serial_register;
-	retval = usb_register(&pl2303_driver);
-	if (retval)
-		goto failed_usb_register;
-	printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_DESC "\n");
-	return 0;
-failed_usb_register:
-	usb_serial_deregister(&pl2303_device);
-failed_usb_serial_register:
-	return retval;
-}
-
-static void __exit pl2303_exit(void)
-{
-	usb_deregister(&pl2303_driver);
-	usb_serial_deregister(&pl2303_device);
-}
+static struct usb_serial_driver * const serial_drivers[] = {
+	&pl2303_device, NULL
+};
 
-module_init(pl2303_init);
-module_exit(pl2303_exit);
+module_usb_serial_driver(serial_drivers, id_table);
 
-MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_DESCRIPTION("Prolific PL2303 USB to serial adaptor driver");
 MODULE_LICENSE("GPL");
-
-module_param(debug, bool, S_IRUGO | S_IWUSR);
-MODULE_PARM_DESC(debug, "Debug enabled or not");
-