1 files changed, 522 insertions, 303 deletions

diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c
index 0cdff38107e..e934e19f49f 100644
--- a/drivers/usb/class/cdc-acm.c
+++ b/drivers/usb/class/cdc-acm.c
@@ -58,12 +58,62 @@ static struct usb_driver acm_driver;
 static struct tty_driver *acm_tty_driver;
 static struct acm *acm_table[ACM_TTY_MINORS];
 
-static DEFINE_MUTEX(open_mutex);
+static DEFINE_MUTEX(acm_table_lock);
 
-#define ACM_READY(acm)	(acm && acm->dev && acm->port.count)
+/*
+ * acm_table accessors
+ */
 
-static const struct tty_port_operations acm_port_ops = {
-};
+/*
+ * Look up an ACM structure by index. If found and not disconnected, increment
+ * its refcount and return it with its mutex held.
+ */
+static struct acm *acm_get_by_index(unsigned index)
+{
+	struct acm *acm;
+
+	mutex_lock(&acm_table_lock);
+	acm = acm_table[index];
+	if (acm) {
+		mutex_lock(&acm->mutex);
+		if (acm->disconnected) {
+			mutex_unlock(&acm->mutex);
+			acm = NULL;
+		} else {
+			tty_port_get(&acm->port);
+			mutex_unlock(&acm->mutex);
+		}
+	}
+	mutex_unlock(&acm_table_lock);
+	return acm;
+}
+
+/*
+ * Try to find an available minor number and if found, associate it with 'acm'.
+ */
+static int acm_alloc_minor(struct acm *acm)
+{
+	int minor;
+
+	mutex_lock(&acm_table_lock);
+	for (minor = 0; minor < ACM_TTY_MINORS; minor++) {
+		if (!acm_table[minor]) {
+			acm_table[minor] = acm;
+			break;
+		}
+	}
+	mutex_unlock(&acm_table_lock);
+
+	return minor;
+}
+
+/* Release the minor number associated with 'acm'.  */
+static void acm_release_minor(struct acm *acm)
+{
+	mutex_lock(&acm_table_lock);
+	acm_table[acm->minor] = NULL;
+	mutex_unlock(&acm_table_lock);
+}
 
 /*
  * Functions for ACM control messages.
@@ -72,13 +122,23 @@ static const struct tty_port_operations acm_port_ops = {
 static int acm_ctrl_msg(struct acm *acm, int request, int value,
 							void *buf, int len)
 {
-	int retval = usb_control_msg(acm->dev, usb_sndctrlpipe(acm->dev, 0),
+	int retval;
+
+	retval = usb_autopm_get_interface(acm->control);
+	if (retval)
+		return retval;
+
+	retval = usb_control_msg(acm->dev, usb_sndctrlpipe(acm->dev, 0),
 		request, USB_RT_ACM, value,
 		acm->control->altsetting[0].desc.bInterfaceNumber,
 		buf, len, 5000);
+
 	dev_dbg(&acm->control->dev,
 			"%s - rq 0x%02x, val %#x, len %#x, result %d\n",
 			__func__, request, value, len, retval);
+
+	usb_autopm_put_interface(acm->control);
+
 	return retval < 0 ? retval : 0;
 }
 
@@ -166,38 +226,6 @@ static int acm_start_wb(struct acm *acm, struct acm_wb *wb)
 	return rc;
 }
 
-static int acm_write_start(struct acm *acm, int wbn)
-{
-	unsigned long flags;
-	struct acm_wb *wb = &acm->wb[wbn];
-	int rc;
-
-	spin_lock_irqsave(&acm->write_lock, flags);
-	if (!acm->dev) {
-		wb->use = 0;
-		spin_unlock_irqrestore(&acm->write_lock, flags);
-		return -ENODEV;
-	}
-
-	dev_vdbg(&acm->data->dev, "%s - susp_count %d\n", __func__,
-							acm->susp_count);
-	usb_autopm_get_interface_async(acm->control);
-	if (acm->susp_count) {
-		if (!acm->delayed_wb)
-			acm->delayed_wb = wb;
-		else
-			usb_autopm_put_interface_async(acm->control);
-		spin_unlock_irqrestore(&acm->write_lock, flags);
-		return 0;	/* A white lie */
-	}
-	usb_mark_last_busy(acm->dev);
-
-	rc = acm_start_wb(acm, wb);
-	spin_unlock_irqrestore(&acm->write_lock, flags);
-
-	return rc;
-
-}
 /*
  * attributes exported through sysfs
  */
@@ -242,9 +270,9 @@ static void acm_ctrl_irq(struct urb *urb)
 {
 	struct acm *acm = urb->context;
 	struct usb_cdc_notification *dr = urb->transfer_buffer;
-	struct tty_struct *tty;
 	unsigned char *data;
 	int newctrl;
+	int difference;
 	int retval;
 	int status = urb->status;
 
@@ -267,9 +295,6 @@ static void acm_ctrl_irq(struct urb *urb)
 		goto exit;
 	}
 
-	if (!ACM_READY(acm))
-		goto exit;
-
 	usb_mark_last_busy(acm->dev);
 
 	data = (unsigned char *)(dr + 1);
@@ -280,33 +305,39 @@ static void acm_ctrl_irq(struct urb *urb)
 		break;
 
 	case USB_CDC_NOTIFY_SERIAL_STATE:
-		tty = tty_port_tty_get(&acm->port);
 		newctrl = get_unaligned_le16(data);
 
-		if (tty) {
-			if (!acm->clocal &&
-				(acm->ctrlin & ~newctrl & ACM_CTRL_DCD)) {
-				dev_dbg(&acm->control->dev,
-					"%s - calling hangup\n", __func__);
-				tty_hangup(tty);
-			}
-			tty_kref_put(tty);
+		if (!acm->clocal && (acm->ctrlin & ~newctrl & ACM_CTRL_DCD)) {
+			dev_dbg(&acm->control->dev, "%s - calling hangup\n",
+					__func__);
+			tty_port_tty_hangup(&acm->port, false);
 		}
 
+		difference = acm->ctrlin ^ newctrl;
+		spin_lock(&acm->read_lock);
 		acm->ctrlin = newctrl;
+		acm->oldcount = acm->iocount;
+
+		if (difference & ACM_CTRL_DSR)
+			acm->iocount.dsr++;
+		if (difference & ACM_CTRL_BRK)
+			acm->iocount.brk++;
+		if (difference & ACM_CTRL_RI)
+			acm->iocount.rng++;
+		if (difference & ACM_CTRL_DCD)
+			acm->iocount.dcd++;
+		if (difference & ACM_CTRL_FRAMING)
+			acm->iocount.frame++;
+		if (difference & ACM_CTRL_PARITY)
+			acm->iocount.parity++;
+		if (difference & ACM_CTRL_OVERRUN)
+			acm->iocount.overrun++;
+		spin_unlock(&acm->read_lock);
+
+		if (difference)
+			wake_up_all(&acm->wioctl);
 
-		dev_dbg(&acm->control->dev,
-			"%s - input control lines: dcd%c dsr%c break%c "
-			"ring%c framing%c parity%c overrun%c\n",
-			__func__,
-			acm->ctrlin & ACM_CTRL_DCD ? '+' : '-',
-			acm->ctrlin & ACM_CTRL_DSR ? '+' : '-',
-			acm->ctrlin & ACM_CTRL_BRK ? '+' : '-',
-			acm->ctrlin & ACM_CTRL_RI  ? '+' : '-',
-			acm->ctrlin & ACM_CTRL_FRAMING ? '+' : '-',
-			acm->ctrlin & ACM_CTRL_PARITY ? '+' : '-',
-			acm->ctrlin & ACM_CTRL_OVERRUN ? '+' : '-');
-			break;
+		break;
 
 	default:
 		dev_dbg(&acm->control->dev,
@@ -363,19 +394,12 @@ static int acm_submit_read_urbs(struct acm *acm, gfp_t mem_flags)
 
 static void acm_process_read_urb(struct acm *acm, struct urb *urb)
 {
-	struct tty_struct *tty;
-
 	if (!urb->actual_length)
 		return;
 
-	tty = tty_port_tty_get(&acm->port);
-	if (!tty)
-		return;
-
-	tty_insert_flip_string(tty, urb->transfer_buffer, urb->actual_length);
-	tty_flip_buffer_push(tty);
-
-	tty_kref_put(tty);
+	tty_insert_flip_string(&acm->port, urb->transfer_buffer,
+			urb->actual_length);
+	tty_flip_buffer_push(&acm->port);
 }
 
 static void acm_read_bulk_callback(struct urb *urb)
@@ -392,19 +416,21 @@ static void acm_read_bulk_callback(struct urb *urb)
 		dev_dbg(&acm->data->dev, "%s - disconnected\n", __func__);
 		return;
 	}
-	usb_mark_last_busy(acm->dev);
 
 	if (urb->status) {
 		dev_dbg(&acm->data->dev, "%s - non-zero urb status: %d\n",
 							__func__, urb->status);
 		return;
 	}
+
+	usb_mark_last_busy(acm->dev);
+
 	acm_process_read_urb(acm, urb);
 
 	/* throttle device if requested by tty */
 	spin_lock_irqsave(&acm->read_lock, flags);
 	acm->throttled = acm->throttle_req;
-	if (!acm->throttled && !acm->susp_count) {
+	if (!acm->throttled) {
 		spin_unlock_irqrestore(&acm->read_lock, flags);
 		acm_submit_read_urb(acm, rb->index, GFP_ATOMIC);
 	} else {
@@ -429,75 +455,105 @@ static void acm_write_bulk(struct urb *urb)
 	spin_lock_irqsave(&acm->write_lock, flags);
 	acm_write_done(acm, wb);
 	spin_unlock_irqrestore(&acm->write_lock, flags);
-	if (ACM_READY(acm))
-		schedule_work(&acm->work);
+	schedule_work(&acm->work);
 }
 
 static void acm_softint(struct work_struct *work)
 {
 	struct acm *acm = container_of(work, struct acm, work);
-	struct tty_struct *tty;
 
 	dev_vdbg(&acm->data->dev, "%s\n", __func__);
 
-	if (!ACM_READY(acm))
-		return;
-	tty = tty_port_tty_get(&acm->port);
-	if (!tty)
-		return;
-	tty_wakeup(tty);
-	tty_kref_put(tty);
+	tty_port_tty_wakeup(&acm->port);
 }
 
 /*
  * TTY handlers
  */
 
-static int acm_tty_open(struct tty_struct *tty, struct file *filp)
+static int acm_tty_install(struct tty_driver *driver, struct tty_struct *tty)
 {
 	struct acm *acm;
-	int rv = -ENODEV;
-
-	mutex_lock(&open_mutex);
+	int retval;
 
-	acm = acm_table[tty->index];
-	if (!acm || !acm->dev)
-		goto out;
-	else
-		rv = 0;
+	dev_dbg(tty->dev, "%s\n", __func__);
 
-	dev_dbg(&acm->control->dev, "%s\n", __func__);
+	acm = acm_get_by_index(tty->index);
+	if (!acm)
+		return -ENODEV;
 
-	set_bit(TTY_NO_WRITE_SPLIT, &tty->flags);
+	retval = tty_standard_install(driver, tty);
+	if (retval)
+		goto error_init_termios;
 
 	tty->driver_data = acm;
-	tty_port_tty_set(&acm->port, tty);
 
-	if (usb_autopm_get_interface(acm->control) < 0)
-		goto early_bail;
+	return 0;
+
+error_init_termios:
+	tty_port_put(&acm->port);
+	return retval;
+}
+
+static int acm_tty_open(struct tty_struct *tty, struct file *filp)
+{
+	struct acm *acm = tty->driver_data;
+
+	dev_dbg(tty->dev, "%s\n", __func__);
+
+	return tty_port_open(&acm->port, tty, filp);
+}
+
+static void acm_port_dtr_rts(struct tty_port *port, int raise)
+{
+	struct acm *acm = container_of(port, struct acm, port);
+	int val;
+	int res;
+
+	if (raise)
+		val = ACM_CTRL_DTR | ACM_CTRL_RTS;
 	else
-		acm->control->needs_remote_wakeup = 1;
+		val = 0;
+
+	/* FIXME: add missing ctrlout locking throughout driver */
+	acm->ctrlout = val;
+
+	res = acm_set_control(acm, val);
+	if (res && (acm->ctrl_caps & USB_CDC_CAP_LINE))
+		dev_err(&acm->control->dev, "failed to set dtr/rts\n");
+}
+
+static int acm_port_activate(struct tty_port *port, struct tty_struct *tty)
+{
+	struct acm *acm = container_of(port, struct acm, port);
+	int retval = -ENODEV;
+	int i;
+
+	dev_dbg(&acm->control->dev, "%s\n", __func__);
 
 	mutex_lock(&acm->mutex);
-	if (acm->port.count++) {
-		mutex_unlock(&acm->mutex);
-		usb_autopm_put_interface(acm->control);
-		goto out;
-	}
+	if (acm->disconnected)
+		goto disconnected;
+
+	retval = usb_autopm_get_interface(acm->control);
+	if (retval)
+		goto error_get_interface;
+
+	/*
+	 * FIXME: Why do we need this? Allocating 64K of physically contiguous
+	 * memory is really nasty...
+	 */
+	set_bit(TTY_NO_WRITE_SPLIT, &tty->flags);
+	acm->control->needs_remote_wakeup = 1;
 
 	acm->ctrlurb->dev = acm->dev;
-	if (usb_submit_urb(acm->ctrlurb, GFP_KERNEL)) {
+	retval = usb_submit_urb(acm->ctrlurb, GFP_KERNEL);
+	if (retval) {
 		dev_err(&acm->control->dev,
 			"%s - usb_submit_urb(ctrl irq) failed\n", __func__);
-		goto bail_out;
+		goto error_submit_urb;
 	}
 
-	if (0 > acm_set_control(acm, acm->ctrlout = ACM_CTRL_DTR | ACM_CTRL_RTS) &&
-	    (acm->ctrl_caps & USB_CDC_CAP_LINE))
-		goto bail_out;
-
-	usb_autopm_put_interface(acm->control);
-
 	/*
 	 * Unthrottle device in case the TTY was closed while throttled.
 	 */
@@ -506,100 +562,96 @@ static int acm_tty_open(struct tty_struct *tty, struct file *filp)
 	acm->throttle_req = 0;
 	spin_unlock_irq(&acm->read_lock);
 
-	if (acm_submit_read_urbs(acm, GFP_KERNEL))
-		goto bail_out;
+	retval = acm_submit_read_urbs(acm, GFP_KERNEL);
+	if (retval)
+		goto error_submit_read_urbs;
 
-	set_bit(ASYNCB_INITIALIZED, &acm->port.flags);
-	rv = tty_port_block_til_ready(&acm->port, tty, filp);
+	usb_autopm_put_interface(acm->control);
 
 	mutex_unlock(&acm->mutex);
-out:
-	mutex_unlock(&open_mutex);
-	return rv;
 
-bail_out:
-	acm->port.count--;
-	mutex_unlock(&acm->mutex);
+	return 0;
+
+error_submit_read_urbs:
+	for (i = 0; i < acm->rx_buflimit; i++)
+		usb_kill_urb(acm->read_urbs[i]);
+	usb_kill_urb(acm->ctrlurb);
+error_submit_urb:
 	usb_autopm_put_interface(acm->control);
-early_bail:
-	mutex_unlock(&open_mutex);
-	tty_port_tty_set(&acm->port, NULL);
-	return -EIO;
+error_get_interface:
+disconnected:
+	mutex_unlock(&acm->mutex);
+
+	return usb_translate_errors(retval);
 }
 
-static void acm_tty_unregister(struct acm *acm)
+static void acm_port_destruct(struct tty_port *port)
 {
-	int i;
+	struct acm *acm = container_of(port, struct acm, port);
 
-	tty_unregister_device(acm_tty_driver, acm->minor);
+	dev_dbg(&acm->control->dev, "%s\n", __func__);
+
+	acm_release_minor(acm);
 	usb_put_intf(acm->control);
-	acm_table[acm->minor] = NULL;
-	usb_free_urb(acm->ctrlurb);
-	for (i = 0; i < ACM_NW; i++)
-		usb_free_urb(acm->wb[i].urb);
-	for (i = 0; i < acm->rx_buflimit; i++)
-		usb_free_urb(acm->read_urbs[i]);
 	kfree(acm->country_codes);
 	kfree(acm);
 }
 
-static void acm_port_down(struct acm *acm)
+static void acm_port_shutdown(struct tty_port *port)
 {
+	struct acm *acm = container_of(port, struct acm, port);
+	struct urb *urb;
+	struct acm_wb *wb;
 	int i;
 
-	if (acm->dev) {
-		usb_autopm_get_interface(acm->control);
-		acm_set_control(acm, acm->ctrlout = 0);
-		usb_kill_urb(acm->ctrlurb);
-		for (i = 0; i < ACM_NW; i++)
-			usb_kill_urb(acm->wb[i].urb);
-		for (i = 0; i < acm->rx_buflimit; i++)
-			usb_kill_urb(acm->read_urbs[i]);
-		acm->control->needs_remote_wakeup = 0;
-		usb_autopm_put_interface(acm->control);
+	dev_dbg(&acm->control->dev, "%s\n", __func__);
+
+	/*
+	 * Need to grab write_lock to prevent race with resume, but no need to
+	 * hold it due to the tty-port initialised flag.
+	 */
+	spin_lock_irq(&acm->write_lock);
+	spin_unlock_irq(&acm->write_lock);
+
+	usb_autopm_get_interface_no_resume(acm->control);
+	acm->control->needs_remote_wakeup = 0;
+	usb_autopm_put_interface(acm->control);
+
+	for (;;) {
+		urb = usb_get_from_anchor(&acm->delayed);
+		if (!urb)
+			break;
+		wb = urb->context;
+		wb->use = 0;
+		usb_autopm_put_interface_async(acm->control);
 	}
+
+	usb_kill_urb(acm->ctrlurb);
+	for (i = 0; i < ACM_NW; i++)
+		usb_kill_urb(acm->wb[i].urb);
+	for (i = 0; i < acm->rx_buflimit; i++)
+		usb_kill_urb(acm->read_urbs[i]);
 }
 
-static void acm_tty_hangup(struct tty_struct *tty)
+static void acm_tty_cleanup(struct tty_struct *tty)
 {
-	struct acm *acm;
-
-	mutex_lock(&open_mutex);
-	acm = tty->driver_data;
-
-	if (!acm)
-		goto out;
+	struct acm *acm = tty->driver_data;
+	dev_dbg(&acm->control->dev, "%s\n", __func__);
+	tty_port_put(&acm->port);
+}
 
+static void acm_tty_hangup(struct tty_struct *tty)
+{
+	struct acm *acm = tty->driver_data;
+	dev_dbg(&acm->control->dev, "%s\n", __func__);
 	tty_port_hangup(&acm->port);
-	acm_port_down(acm);
-
-out:
-	mutex_unlock(&open_mutex);
 }
 
 static void acm_tty_close(struct tty_struct *tty, struct file *filp)
 {
 	struct acm *acm = tty->driver_data;
-
-	/* Perform the closing process and see if we need to do the hardware
-	   shutdown */
-	if (!acm)
-		return;
-
-	mutex_lock(&open_mutex);
-	if (tty_port_close_start(&acm->port, tty, filp) == 0) {
-		if (!acm->dev) {
-			tty_port_tty_set(&acm->port, NULL);
-			acm_tty_unregister(acm);
-			tty->driver_data = NULL;
-		}
-		mutex_unlock(&open_mutex);
-		return;
-	}
-	acm_port_down(acm);
-	tty_port_close_end(&acm->port, tty);
-	tty_port_tty_set(&acm->port, NULL);
-	mutex_unlock(&open_mutex);
+	dev_dbg(&acm->control->dev, "%s\n", __func__);
+	tty_port_close(&acm->port, tty, filp);
 }
 
 static int acm_tty_write(struct tty_struct *tty,
@@ -611,8 +663,6 @@ static int acm_tty_write(struct tty_struct *tty,
 	int wbn;
 	struct acm_wb *wb;
 
-	if (!ACM_READY(acm))
-		return -EINVAL;
 	if (!count)
 		return 0;
 
@@ -626,13 +676,33 @@ static int acm_tty_write(struct tty_struct *tty,
 	}
 	wb = &acm->wb[wbn];
 
+	if (!acm->dev) {
+		wb->use = 0;
+		spin_unlock_irqrestore(&acm->write_lock, flags);
+		return -ENODEV;
+	}
+
 	count = (count > acm->writesize) ? acm->writesize : count;
 	dev_vdbg(&acm->data->dev, "%s - write %d\n", __func__, count);
 	memcpy(wb->buf, buf, count);
 	wb->len = count;
+
+	stat = usb_autopm_get_interface_async(acm->control);
+	if (stat) {
+		wb->use = 0;
+		spin_unlock_irqrestore(&acm->write_lock, flags);
+		return stat;
+	}
+
+	if (acm->susp_count) {
+		usb_anchor_urb(wb->urb, &acm->delayed);
+		spin_unlock_irqrestore(&acm->write_lock, flags);
+		return count;
+	}
+
+	stat = acm_start_wb(acm, wb);
 	spin_unlock_irqrestore(&acm->write_lock, flags);
 
-	stat = acm_write_start(acm, wbn);
 	if (stat < 0)
 		return stat;
 	return count;
@@ -641,8 +711,6 @@ static int acm_tty_write(struct tty_struct *tty,
 static int acm_tty_write_room(struct tty_struct *tty)
 {
 	struct acm *acm = tty->driver_data;
-	if (!ACM_READY(acm))
-		return -EINVAL;
 	/*
 	 * Do not let the line discipline to know that we have a reserve,
 	 * or it might get too enthusiastic.
@@ -653,7 +721,11 @@ static int acm_tty_write_room(struct tty_struct *tty)
 static int acm_tty_chars_in_buffer(struct tty_struct *tty)
 {
 	struct acm *acm = tty->driver_data;
-	if (!ACM_READY(acm))
+	/*
+	 * if the device was unplugged then any remaining characters fell out
+	 * of the connector ;)
+	 */
+	if (acm->disconnected)
 		return 0;
 	/*
 	 * This is inaccurate (overcounts), but it works.
@@ -665,9 +737,6 @@ static void acm_tty_throttle(struct tty_struct *tty)
 {
 	struct acm *acm = tty->driver_data;
 
-	if (!ACM_READY(acm))
-		return;
-
 	spin_lock_irq(&acm->read_lock);
 	acm->throttle_req = 1;
 	spin_unlock_irq(&acm->read_lock);
@@ -678,9 +747,6 @@ static void acm_tty_unthrottle(struct tty_struct *tty)
 	struct acm *acm = tty->driver_data;
 	unsigned int was_throttled;
 
-	if (!ACM_READY(acm))
-		return;
-
 	spin_lock_irq(&acm->read_lock);
 	was_throttled = acm->throttled;
 	acm->throttled = 0;
@@ -695,8 +761,7 @@ static int acm_tty_break_ctl(struct tty_struct *tty, int state)
 {
 	struct acm *acm = tty->driver_data;
 	int retval;
-	if (!ACM_READY(acm))
-		return -EINVAL;
+
 	retval = acm_send_break(acm, state ? 0xffff : 0);
 	if (retval < 0)
 		dev_dbg(&acm->control->dev, "%s - send break failed\n",
@@ -708,9 +773,6 @@ static int acm_tty_tiocmget(struct tty_struct *tty)
 {
 	struct acm *acm = tty->driver_data;
 
-	if (!ACM_READY(acm))
-		return -EINVAL;
-
 	return (acm->ctrlout & ACM_CTRL_DTR ? TIOCM_DTR : 0) |
 	       (acm->ctrlout & ACM_CTRL_RTS ? TIOCM_RTS : 0) |
 	       (acm->ctrlin  & ACM_CTRL_DSR ? TIOCM_DSR : 0) |
@@ -725,9 +787,6 @@ static int acm_tty_tiocmset(struct tty_struct *tty,
 	struct acm *acm = tty->driver_data;
 	unsigned int newctrl;
 
-	if (!ACM_READY(acm))
-		return -EINVAL;
-
 	newctrl = acm->ctrlout;
 	set = (set & TIOCM_DTR ? ACM_CTRL_DTR : 0) |
 					(set & TIOCM_RTS ? ACM_CTRL_RTS : 0);
@@ -741,36 +800,163 @@ static int acm_tty_tiocmset(struct tty_struct *tty,
 	return acm_set_control(acm, acm->ctrlout = newctrl);
 }
 
+static int get_serial_info(struct acm *acm, struct serial_struct __user *info)
+{
+	struct serial_struct tmp;
+
+	if (!info)
+		return -EINVAL;
+
+	memset(&tmp, 0, sizeof(tmp));
+	tmp.flags = ASYNC_LOW_LATENCY;
+	tmp.xmit_fifo_size = acm->writesize;
+	tmp.baud_base = le32_to_cpu(acm->line.dwDTERate);
+	tmp.close_delay	= acm->port.close_delay / 10;
+	tmp.closing_wait = acm->port.closing_wait == ASYNC_CLOSING_WAIT_NONE ?
+				ASYNC_CLOSING_WAIT_NONE :
+				acm->port.closing_wait / 10;
+
+	if (copy_to_user(info, &tmp, sizeof(tmp)))
+		return -EFAULT;
+	else
+		return 0;
+}
+
+static int set_serial_info(struct acm *acm,
+				struct serial_struct __user *newinfo)
+{
+	struct serial_struct new_serial;
+	unsigned int closing_wait, close_delay;
+	int retval = 0;
+
+	if (copy_from_user(&new_serial, newinfo, sizeof(new_serial)))
+		return -EFAULT;
+
+	close_delay = new_serial.close_delay * 10;
+	closing_wait = new_serial.closing_wait == ASYNC_CLOSING_WAIT_NONE ?
+			ASYNC_CLOSING_WAIT_NONE : new_serial.closing_wait * 10;
+
+	mutex_lock(&acm->port.mutex);
+
+	if (!capable(CAP_SYS_ADMIN)) {
+		if ((close_delay != acm->port.close_delay) ||
+		    (closing_wait != acm->port.closing_wait))
+			retval = -EPERM;
+		else
+			retval = -EOPNOTSUPP;
+	} else {
+		acm->port.close_delay  = close_delay;
+		acm->port.closing_wait = closing_wait;
+	}
+
+	mutex_unlock(&acm->port.mutex);
+	return retval;
+}
+
+static int wait_serial_change(struct acm *acm, unsigned long arg)
+{
+	int rv = 0;
+	DECLARE_WAITQUEUE(wait, current);
+	struct async_icount old, new;
+
+	if (arg & (TIOCM_DSR | TIOCM_RI | TIOCM_CD ))
+		return -EINVAL;
+	do {
+		spin_lock_irq(&acm->read_lock);
+		old = acm->oldcount;
+		new = acm->iocount;
+		acm->oldcount = new;
+		spin_unlock_irq(&acm->read_lock);
+
+		if ((arg & TIOCM_DSR) &&
+			old.dsr != new.dsr)
+			break;
+		if ((arg & TIOCM_CD)  &&
+			old.dcd != new.dcd)
+			break;
+		if ((arg & TIOCM_RI) &&
+			old.rng != new.rng)
+			break;
+
+		add_wait_queue(&acm->wioctl, &wait);
+		set_current_state(TASK_INTERRUPTIBLE);
+		schedule();
+		remove_wait_queue(&acm->wioctl, &wait);
+		if (acm->disconnected) {
+			if (arg & TIOCM_CD)
+				break;
+			else
+				rv = -ENODEV;
+		} else {
+			if (signal_pending(current))
+				rv = -ERESTARTSYS;
+		}
+	} while (!rv);
+
+	
+
+	return rv;
+}
+
+static int get_serial_usage(struct acm *acm,
+			    struct serial_icounter_struct __user *count)
+{
+	struct serial_icounter_struct icount;
+	int rv = 0;
+
+	memset(&icount, 0, sizeof(icount));
+	icount.dsr = acm->iocount.dsr;
+	icount.rng = acm->iocount.rng;
+	icount.dcd = acm->iocount.dcd;
+	icount.frame = acm->iocount.frame;
+	icount.overrun = acm->iocount.overrun;
+	icount.parity = acm->iocount.parity;
+	icount.brk = acm->iocount.brk;
+
+	if (copy_to_user(count, &icount, sizeof(icount)) > 0)
+		rv = -EFAULT;
+
+	return rv;
+}
+
 static int acm_tty_ioctl(struct tty_struct *tty,
 					unsigned int cmd, unsigned long arg)
 {
 	struct acm *acm = tty->driver_data;
+	int rv = -ENOIOCTLCMD;
 
-	if (!ACM_READY(acm))
-		return -EINVAL;
+	switch (cmd) {
+	case TIOCGSERIAL: /* gets serial port data */
+		rv = get_serial_info(acm, (struct serial_struct __user *) arg);
+		break;
+	case TIOCSSERIAL:
+		rv = set_serial_info(acm, (struct serial_struct __user *) arg);
+		break;
+	case TIOCMIWAIT:
+		rv = usb_autopm_get_interface(acm->control);
+		if (rv < 0) {
+			rv = -EIO;
+			break;
+		}
+		rv = wait_serial_change(acm, arg);
+		usb_autopm_put_interface(acm->control);
+		break;
+	case TIOCGICOUNT:
+		rv = get_serial_usage(acm, (struct serial_icounter_struct __user *) arg);
+		break;
+	}
 
-	return -ENOIOCTLCMD;
+	return rv;
 }
 
-static const __u32 acm_tty_speed[] = {
-	0, 50, 75, 110, 134, 150, 200, 300, 600,
-	1200, 1800, 2400, 4800, 9600, 19200, 38400,
-	57600, 115200, 230400, 460800, 500000, 576000,
-	921600, 1000000, 1152000, 1500000, 2000000,
-	2500000, 3000000, 3500000, 4000000
-};
-
 static void acm_tty_set_termios(struct tty_struct *tty,
 						struct ktermios *termios_old)
 {
 	struct acm *acm = tty->driver_data;
-	struct ktermios *termios = tty->termios;
+	struct ktermios *termios = &tty->termios;
 	struct usb_cdc_line_coding newline;
 	int newctrl = acm->ctrlout;
 
-	if (!ACM_READY(acm))
-		return;
-
 	newline.dwDTERate = cpu_to_le32(tty_get_baud_rate(tty));
 	newline.bCharFormat = termios->c_cflag & CSTOPB ? 2 : 0;
 	newline.bParityType = termios->c_cflag & PARENB ?
@@ -814,6 +1000,13 @@ static void acm_tty_set_termios(struct tty_struct *tty,
 	}
 }
 
+static const struct tty_port_operations acm_port_ops = {
+	.dtr_rts = acm_port_dtr_rts,
+	.shutdown = acm_port_shutdown,
+	.activate = acm_port_activate,
+	.destruct = acm_port_destruct,
+};
+
 /*
  * USB probe and disconnect routines.
  */
@@ -886,9 +1079,15 @@ static int acm_probe(struct usb_interface *intf,
 	int num_rx_buf;
 	int i;
 	int combined_interfaces = 0;
+	struct device *tty_dev;
+	int rv = -ENOMEM;
 
 	/* normal quirks */
 	quirks = (unsigned long)id->driver_info;
+
+	if (quirks == IGNORE_DEVICE)
+		return -ENODEV;
+
 	num_rx_buf = (quirks == SINGLE_RX_URB) ? 1 : ACM_NR;
 
 	/* handle quirks deadly to normal probing*/
@@ -945,7 +1144,7 @@ static int acm_probe(struct usb_interface *intf,
 		case USB_CDC_CALL_MANAGEMENT_TYPE:
 			call_management_function = buffer[3];
 			call_interface_num = buffer[4];
-			if ( (quirks & NOT_A_MODEM) == 0 && (call_management_function & 3) != 3)
+			if ((quirks & NOT_A_MODEM) == 0 && (call_management_function & 3) != 3)
 				dev_err(&intf->dev, "This device cannot do calls on its own. It is not a modem.\n");
 			break;
 		default:
@@ -1074,12 +1273,6 @@ skip_normal_probe:
 	}
 made_compressed_probe:
 	dev_dbg(&intf->dev, "interfaces are valid\n");
-	for (minor = 0; minor < ACM_TTY_MINORS && acm_table[minor]; minor++);
-
-	if (minor == ACM_TTY_MINORS) {
-		dev_err(&intf->dev, "no more free acm devices\n");
-		return -ENODEV;
-	}
 
 	acm = kzalloc(sizeof(struct acm), GFP_KERNEL);
 	if (acm == NULL) {
@@ -1087,6 +1280,13 @@ made_compressed_probe:
 		goto alloc_fail;
 	}
 
+	minor = acm_alloc_minor(acm);
+	if (minor == ACM_TTY_MINORS) {
+		dev_err(&intf->dev, "no more free acm devices\n");
+		kfree(acm);
+		return -ENODEV;
+	}
+
 	ctrlsize = usb_endpoint_maxp(epctrl);
 	readsize = usb_endpoint_maxp(epread) *
 				(quirks == SINGLE_RX_URB ? 1 : 2);
@@ -1103,6 +1303,7 @@ made_compressed_probe:
 	acm->readsize = readsize;
 	acm->rx_buflimit = num_rx_buf;
 	INIT_WORK(&acm->work, acm_softint);
+	init_waitqueue_head(&acm->wioctl);
 	spin_lock_init(&acm->write_lock);
 	spin_lock_init(&acm->read_lock);
 	mutex_init(&acm->mutex);
@@ -1112,6 +1313,7 @@ made_compressed_probe:
 		acm->bInterval = epread->bInterval;
 	tty_port_init(&acm->port);
 	acm->port.ops = &acm_port_ops;
+	init_usb_anchor(&acm->delayed);
 
 	buf = usb_alloc_coherent(usb_dev, ctrlsize, GFP_KERNEL, &acm->ctrl_dma);
 	if (!buf) {
@@ -1231,14 +1433,12 @@ skip_countries:
 			 usb_rcvintpipe(usb_dev, epctrl->bEndpointAddress),
 			 acm->ctrl_buffer, ctrlsize, acm_ctrl_irq, acm,
 			 /* works around buggy devices */
-			 epctrl->bInterval ? epctrl->bInterval : 0xff);
+			 epctrl->bInterval ? epctrl->bInterval : 16);
 	acm->ctrlurb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 	acm->ctrlurb->transfer_dma = acm->ctrl_dma;
 
 	dev_info(&intf->dev, "ttyACM%d: USB ACM device\n", minor);
 
-	acm_set_control(acm, acm->ctrlout);
-
 	acm->line.dwDTERate = cpu_to_le32(9600);
 	acm->line.bDataBits = 8;
 	acm_set_line(acm, &acm->line);
@@ -1247,12 +1447,24 @@ skip_countries:
 	usb_set_intfdata(data_interface, acm);
 
 	usb_get_intf(control_interface);
-	tty_register_device(acm_tty_driver, minor, &control_interface->dev);
-
-	acm_table[minor] = acm;
+	tty_dev = tty_port_register_device(&acm->port, acm_tty_driver, minor,
+			&control_interface->dev);
+	if (IS_ERR(tty_dev)) {
+		rv = PTR_ERR(tty_dev);
+		goto alloc_fail8;
+	}
 
 	return 0;
+alloc_fail8:
+	if (acm->country_codes) {
+		device_remove_file(&acm->control->dev,
+				&dev_attr_wCountryCodes);
+		device_remove_file(&acm->control->dev,
+				&dev_attr_iCountryCodeRelDate);
+	}
+	device_remove_file(&acm->control->dev, &dev_attr_bmCapabilities);
 alloc_fail7:
+	usb_set_intfdata(intf, NULL);
 	for (i = 0; i < ACM_NW; i++)
 		usb_free_urb(acm->wb[i].urb);
 alloc_fail6:
@@ -1265,9 +1477,10 @@ alloc_fail5:
 alloc_fail4:
 	usb_free_coherent(usb_dev, ctrlsize, acm->ctrl_buffer, acm->ctrl_dma);
 alloc_fail2:
+	acm_release_minor(acm);
 	kfree(acm);
 alloc_fail:
-	return -ENOMEM;
+	return rv;
 }
 
 static void stop_data_traffic(struct acm *acm)
@@ -1290,46 +1503,52 @@ static void acm_disconnect(struct usb_interface *intf)
 	struct acm *acm = usb_get_intfdata(intf);
 	struct usb_device *usb_dev = interface_to_usbdev(intf);
 	struct tty_struct *tty;
+	int i;
+
+	dev_dbg(&intf->dev, "%s\n", __func__);
 
 	/* sibling interface is already cleaning up */
 	if (!acm)
 		return;
 
-	mutex_lock(&open_mutex);
+	mutex_lock(&acm->mutex);
+	acm->disconnected = true;
 	if (acm->country_codes) {
 		device_remove_file(&acm->control->dev,
 				&dev_attr_wCountryCodes);
 		device_remove_file(&acm->control->dev,
 				&dev_attr_iCountryCodeRelDate);
 	}
+	wake_up_all(&acm->wioctl);
 	device_remove_file(&acm->control->dev, &dev_attr_bmCapabilities);
-	acm->dev = NULL;
 	usb_set_intfdata(acm->control, NULL);
 	usb_set_intfdata(acm->data, NULL);
+	mutex_unlock(&acm->mutex);
+
+	tty = tty_port_tty_get(&acm->port);
+	if (tty) {
+		tty_vhangup(tty);
+		tty_kref_put(tty);
+	}
 
 	stop_data_traffic(acm);
 
+	tty_unregister_device(acm_tty_driver, acm->minor);
+
+	usb_free_urb(acm->ctrlurb);
+	for (i = 0; i < ACM_NW; i++)
+		usb_free_urb(acm->wb[i].urb);
+	for (i = 0; i < acm->rx_buflimit; i++)
+		usb_free_urb(acm->read_urbs[i]);
 	acm_write_buffers_free(acm);
-	usb_free_coherent(usb_dev, acm->ctrlsize, acm->ctrl_buffer,
-			  acm->ctrl_dma);
+	usb_free_coherent(usb_dev, acm->ctrlsize, acm->ctrl_buffer, acm->ctrl_dma);
 	acm_read_buffers_free(acm);
 
 	if (!acm->combined_interfaces)
 		usb_driver_release_interface(&acm_driver, intf == acm->control ?
 					acm->data : acm->control);
 
-	if (acm->port.count == 0) {
-		acm_tty_unregister(acm);
-		mutex_unlock(&open_mutex);
-		return;
-	}
-
-	mutex_unlock(&open_mutex);
-	tty = tty_port_tty_get(&acm->port);
-	if (tty) {
-		tty_hangup(tty);
-		tty_kref_put(tty);
-	}
+	tty_port_put(&acm->port);
 }
 
 #ifdef CONFIG_PM
@@ -1338,64 +1557,44 @@ static int acm_suspend(struct usb_interface *intf, pm_message_t message)
 	struct acm *acm = usb_get_intfdata(intf);
 	int cnt;
 
+	spin_lock_irq(&acm->write_lock);
 	if (PMSG_IS_AUTO(message)) {
-		int b;
-
-		spin_lock_irq(&acm->write_lock);
-		b = acm->transmitting;
-		spin_unlock_irq(&acm->write_lock);
-		if (b)
+		if (acm->transmitting) {
+			spin_unlock_irq(&acm->write_lock);
 			return -EBUSY;
+		}
 	}
-
-	spin_lock_irq(&acm->read_lock);
-	spin_lock(&acm->write_lock);
 	cnt = acm->susp_count++;
-	spin_unlock(&acm->write_lock);
-	spin_unlock_irq(&acm->read_lock);
+	spin_unlock_irq(&acm->write_lock);
 
 	if (cnt)
 		return 0;
-	/*
-	we treat opened interfaces differently,
-	we must guard against open
-	*/
-	mutex_lock(&acm->mutex);
 
-	if (acm->port.count)
-		stop_data_traffic(acm);
+	stop_data_traffic(acm);
 
-	mutex_unlock(&acm->mutex);
 	return 0;
 }
 
 static int acm_resume(struct usb_interface *intf)
 {
 	struct acm *acm = usb_get_intfdata(intf);
-	struct acm_wb *wb;
+	struct urb *urb;
 	int rv = 0;
-	int cnt;
 
-	spin_lock_irq(&acm->read_lock);
-	acm->susp_count -= 1;
-	cnt = acm->susp_count;
-	spin_unlock_irq(&acm->read_lock);
+	spin_lock_irq(&acm->write_lock);
 
-	if (cnt)
-		return 0;
+	if (--acm->susp_count)
+		goto out;
 
-	mutex_lock(&acm->mutex);
-	if (acm->port.count) {
-		rv = usb_submit_urb(acm->ctrlurb, GFP_NOIO);
+	if (test_bit(ASYNCB_INITIALIZED, &acm->port.flags)) {
+		rv = usb_submit_urb(acm->ctrlurb, GFP_ATOMIC);
 
-		spin_lock_irq(&acm->write_lock);
-		if (acm->delayed_wb) {
-			wb = acm->delayed_wb;
-			acm->delayed_wb = NULL;
-			spin_unlock_irq(&acm->write_lock);
-			acm_start_wb(acm, wb);
-		} else {
-			spin_unlock_irq(&acm->write_lock);
+		for (;;) {
+			urb = usb_get_from_anchor(&acm->delayed);
+			if (!urb)
+				break;
+
+			acm_start_wb(acm, urb->context);
 		}
 
 		/*
@@ -1403,30 +1602,23 @@ static int acm_resume(struct usb_interface *intf)
 		 * do the write path at all cost
 		 */
 		if (rv < 0)
-			goto err_out;
+			goto out;
 
-		rv = acm_submit_read_urbs(acm, GFP_NOIO);
+		rv = acm_submit_read_urbs(acm, GFP_ATOMIC);
 	}
+out:
+	spin_unlock_irq(&acm->write_lock);
 
-err_out:
-	mutex_unlock(&acm->mutex);
 	return rv;
 }
 
 static int acm_reset_resume(struct usb_interface *intf)
 {
 	struct acm *acm = usb_get_intfdata(intf);
-	struct tty_struct *tty;
 
-	mutex_lock(&acm->mutex);
-	if (acm->port.count) {
-		tty = tty_port_tty_get(&acm->port);
-		if (tty) {
-			tty_hangup(tty);
-			tty_kref_put(tty);
-		}
-	}
-	mutex_unlock(&acm->mutex);
+	if (test_bit(ASYNCB_INITIALIZED, &acm->port.flags))
+		tty_port_tty_hangup(&acm->port, false);
+
 	return acm_resume(intf);
 }
 
@@ -1448,6 +1640,8 @@ static int acm_reset_resume(struct usb_interface *intf)
 
 static const struct usb_device_id acm_ids[] = {
 	/* quirky and broken devices */
+	{ USB_DEVICE(0x17ef, 0x7000), /* Lenovo USB modem */
+	.driver_info = NO_UNION_NORMAL, },/* has no union descriptor */
 	{ USB_DEVICE(0x0870, 0x0001), /* Metricom GS Modem */
 	.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
 	},
@@ -1491,13 +1685,27 @@ static const struct usb_device_id acm_ids[] = {
 	},
 	/* Motorola H24 HSPA module: */
 	{ USB_DEVICE(0x22b8, 0x2d91) }, /* modem                                */
-	{ USB_DEVICE(0x22b8, 0x2d92) }, /* modem           + diagnostics        */
-	{ USB_DEVICE(0x22b8, 0x2d93) }, /* modem + AT port                      */
-	{ USB_DEVICE(0x22b8, 0x2d95) }, /* modem + AT port + diagnostics        */
-	{ USB_DEVICE(0x22b8, 0x2d96) }, /* modem                         + NMEA */
-	{ USB_DEVICE(0x22b8, 0x2d97) }, /* modem           + diagnostics + NMEA */
-	{ USB_DEVICE(0x22b8, 0x2d99) }, /* modem + AT port               + NMEA */
-	{ USB_DEVICE(0x22b8, 0x2d9a) }, /* modem + AT port + diagnostics + NMEA */
+	{ USB_DEVICE(0x22b8, 0x2d92),   /* modem           + diagnostics        */
+	.driver_info = NO_UNION_NORMAL, /* handle only modem interface          */
+	},
+	{ USB_DEVICE(0x22b8, 0x2d93),   /* modem + AT port                      */
+	.driver_info = NO_UNION_NORMAL, /* handle only modem interface          */
+	},
+	{ USB_DEVICE(0x22b8, 0x2d95),   /* modem + AT port + diagnostics        */
+	.driver_info = NO_UNION_NORMAL, /* handle only modem interface          */
+	},
+	{ USB_DEVICE(0x22b8, 0x2d96),   /* modem                         + NMEA */
+	.driver_info = NO_UNION_NORMAL, /* handle only modem interface          */
+	},
+	{ USB_DEVICE(0x22b8, 0x2d97),   /* modem           + diagnostics + NMEA */
+	.driver_info = NO_UNION_NORMAL, /* handle only modem interface          */
+	},
+	{ USB_DEVICE(0x22b8, 0x2d99),   /* modem + AT port               + NMEA */
+	.driver_info = NO_UNION_NORMAL, /* handle only modem interface          */
+	},
+	{ USB_DEVICE(0x22b8, 0x2d9a),   /* modem + AT port + diagnostics + NMEA */
+	.driver_info = NO_UNION_NORMAL, /* handle only modem interface          */
+	},
 
 	{ USB_DEVICE(0x0572, 0x1329), /* Hummingbird huc56s (Conexant) */
 	.driver_info = NO_UNION_NORMAL, /* union descriptor misplaced on
@@ -1598,6 +1806,15 @@ static const struct usb_device_id acm_ids[] = {
 	.driver_info = NO_DATA_INTERFACE,
 	},
 
+#if IS_ENABLED(CONFIG_INPUT_IMS_PCU)
+	{ USB_DEVICE(0x04d8, 0x0082),	/* Application mode */
+	.driver_info = IGNORE_DEVICE,
+	},
+	{ USB_DEVICE(0x04d8, 0x0083),	/* Bootloader mode */
+	.driver_info = IGNORE_DEVICE,
+	},
+#endif
+
 	/* control interfaces without any protocol set */
 	{ USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
 		USB_CDC_PROTO_NONE) },
@@ -1634,6 +1851,7 @@ static struct usb_driver acm_driver = {
 #ifdef CONFIG_PM
 	.supports_autosuspend = 1,
 #endif
+	.disable_hub_initiated_lpm = 1,
 };
 
 /*
@@ -1641,8 +1859,10 @@ static struct usb_driver acm_driver = {
  */
 
 static const struct tty_operations acm_ops = {
+	.install =		acm_tty_install,
 	.open =			acm_tty_open,
 	.close =		acm_tty_close,
+	.cleanup =		acm_tty_cleanup,
 	.hangup =		acm_tty_hangup,
 	.write =		acm_tty_write,
 	.write_room =		acm_tty_write_room,
@@ -1666,7 +1886,6 @@ static int __init acm_init(void)
 	acm_tty_driver = alloc_tty_driver(ACM_TTY_MINORS);
 	if (!acm_tty_driver)
 		return -ENOMEM;
-	acm_tty_driver->owner = THIS_MODULE,
 	acm_tty_driver->driver_name = "acm",
 	acm_tty_driver->name = "ttyACM",
 	acm_tty_driver->major = ACM_TTY_MAJOR,