1 files changed, 53 insertions, 29 deletions

diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c
index 34d4eb98829e..975d556b4787 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