1 files changed, 53 insertions, 29 deletions

diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c
index 34d4eb98829..975d556b478 100644
--- a/drivers/usb/class/cdc-acm.c
+++ b/drivers/usb/class/cdc-acm.c
@@ -170,6 +170,7 @@ static void acm_write_done(struct acm *acm, struct acm_wb *wb)
 {
 	wb->use = 0;
 	acm->transmitting--;
+	usb_autopm_put_interface_async(acm->control);
 }
 
 /*
@@ -211,9 +212,12 @@ static int acm_write_start(struct acm *acm, int wbn)
 	}
 
 	dbg("%s susp_count: %d", __func__, acm->susp_count);
+	usb_autopm_get_interface_async(acm->control);
 	if (acm->susp_count) {
-		acm->delayed_wb = wb;
-		schedule_work(&acm->waker);
+		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 */
 	}
@@ -424,7 +428,6 @@ next_buffer:
 		throttled = acm->throttle;
 		spin_unlock_irqrestore(&acm->throttle_lock, flags);
 		if (!throttled) {
-			tty_buffer_request_room(tty, buf->size);
 			tty_insert_flip_string(tty, buf->base, buf->size);
 			tty_flip_buffer_push(tty);
 		} else {
@@ -534,23 +537,6 @@ static void acm_softint(struct work_struct *work)
 	tty_kref_put(tty);
 }
 
-static void acm_waker(struct work_struct *waker)
-{
-	struct acm *acm = container_of(waker, struct acm, waker);
-	int rv;
-
-	rv = usb_autopm_get_interface(acm->control);
-	if (rv < 0) {
-		dev_err(&acm->dev->dev, "Autopm failure in %s\n", __func__);
-		return;
-	}
-	if (acm->delayed_wb) {
-		acm_start_wb(acm, acm->delayed_wb);
-		acm->delayed_wb = NULL;
-	}
-	usb_autopm_put_interface(acm->control);
-}
-
 /*
  * TTY handlers
  */
@@ -566,7 +552,7 @@ static int acm_tty_open(struct tty_struct *tty, struct file *filp)
 
 	acm = acm_table[tty->index];
 	if (!acm || !acm->dev)
-		goto err_out;
+		goto out;
 	else
 		rv = 0;
 
@@ -582,8 +568,9 @@ static int acm_tty_open(struct tty_struct *tty, struct file *filp)
 
 	mutex_lock(&acm->mutex);
 	if (acm->port.count++) {
+		mutex_unlock(&acm->mutex);
 		usb_autopm_put_interface(acm->control);
-		goto done;
+		goto out;
 	}
 
 	acm->ctrlurb->dev = acm->dev;
@@ -612,18 +599,18 @@ static int acm_tty_open(struct tty_struct *tty, struct file *filp)
 	set_bit(ASYNCB_INITIALIZED, &acm->port.flags);
 	rv = tty_port_block_til_ready(&acm->port, tty, filp);
 	tasklet_schedule(&acm->urb_task);
-done:
+
 	mutex_unlock(&acm->mutex);
-err_out:
+out:
 	mutex_unlock(&open_mutex);
 	return rv;
 
 full_bailout:
 	usb_kill_urb(acm->ctrlurb);
 bail_out:
-	usb_autopm_put_interface(acm->control);
 	acm->port.count--;
 	mutex_unlock(&acm->mutex);
+	usb_autopm_put_interface(acm->control);
 early_bail:
 	mutex_unlock(&open_mutex);
 	tty_port_tty_set(&acm->port, NULL);
@@ -1023,7 +1010,7 @@ 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 ((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:
@@ -1178,7 +1165,6 @@ made_compressed_probe:
 	acm->urb_task.func = acm_rx_tasklet;
 	acm->urb_task.data = (unsigned long) acm;
 	INIT_WORK(&acm->work, acm_softint);
-	INIT_WORK(&acm->waker, acm_waker);
 	init_waitqueue_head(&acm->drain_wait);
 	spin_lock_init(&acm->throttle_lock);
 	spin_lock_init(&acm->write_lock);
@@ -1343,7 +1329,6 @@ static void stop_data_traffic(struct acm *acm)
 	tasklet_enable(&acm->urb_task);
 
 	cancel_work_sync(&acm->work);
-	cancel_work_sync(&acm->waker);
 }
 
 static void acm_disconnect(struct usb_interface *intf)
@@ -1435,6 +1420,7 @@ static int acm_suspend(struct usb_interface *intf, pm_message_t message)
 static int acm_resume(struct usb_interface *intf)
 {
 	struct acm *acm = usb_get_intfdata(intf);
+	struct acm_wb *wb;
 	int rv = 0;
 	int cnt;
 
@@ -1449,6 +1435,21 @@ static int acm_resume(struct usb_interface *intf)
 	mutex_lock(&acm->mutex);
 	if (acm->port.count) {
 		rv = usb_submit_urb(acm->ctrlurb, GFP_NOIO);
+
+		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, acm->delayed_wb);
+		} else {
+			spin_unlock_irq(&acm->write_lock);
+		}
+
+		/*
+		 * delayed error checking because we must
+		 * do the write path at all cost
+		 */
 		if (rv < 0)
 			goto err_out;
 
@@ -1460,6 +1461,23 @@ err_out:
 	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);
+	return acm_resume(intf);
+}
+
 #endif /* CONFIG_PM */
 
 #define NOKIA_PCSUITE_ACM_INFO(x) \
@@ -1471,7 +1489,7 @@ err_out:
  * USB driver structure.
  */
 
-static struct usb_device_id acm_ids[] = {
+static const struct usb_device_id acm_ids[] = {
 	/* quirky and broken devices */
 	{ USB_DEVICE(0x0870, 0x0001), /* Metricom GS Modem */
 	.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
@@ -1576,6 +1594,11 @@ static struct usb_device_id acm_ids[] = {
 
 	/* NOTE: non-Nokia COMM/ACM/0xff is likely MSFT RNDIS... NOT a modem! */
 
+	/* Support Lego NXT using pbLua firmware */
+	{ USB_DEVICE(0x0694, 0xff00),
+	.driver_info = NOT_A_MODEM,
+       	},
+
 	/* control interfaces with various AT-command sets */
 	{ USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
 		USB_CDC_ACM_PROTO_AT_V25TER) },
@@ -1602,6 +1625,7 @@ static struct usb_driver acm_driver = {
 #ifdef CONFIG_PM
 	.suspend =	acm_suspend,
 	.resume =	acm_resume,
+	.reset_resume =	acm_reset_resume,
 #endif
 	.id_table =	acm_ids,
 #ifdef CONFIG_PM