[PATCH] usb speedtch: convert to using usb_kill_urb

Unlike usb_unlink_urb, usb_kill_urb guarantees that completion handlers have
finished running before it returns.  The bunch of disconnect code that waited
for completion handlers can now go away.
Signed-off-by: Duncan Sands <baldrick@free.fr>
Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>

drivers/usb/misc/speedtch.c

@@ -1220,9 +1220,7 @@ static int udsl_usb_probe (struct usb_interface *intf, const struct usb_device_i
 static void udsl_usb_disconnect (struct usb_interface *intf)
 {
 	struct udsl_instance_data *instance = usb_get_intfdata (intf);
-	struct list_head *pos;
-	unsigned int count;
-	int result, i;
+	int i;
 
 	dbg ("udsl_usb_disconnect entered");
 
@@ -1237,27 +1235,7 @@ static void udsl_usb_disconnect (struct usb_interface *intf)
 	tasklet_disable (&instance->receive_tasklet);
 
 	for (i = 0; i < num_rcv_urbs; i++)
-		if ((result = usb_unlink_urb (instance->receivers [i].urb)) < 0)
-			dbg ("udsl_usb_disconnect: usb_unlink_urb on receive urb %d returned %d!", i, result);
-
-	/* wait for completion handlers to finish */
-	do {
-		count = 0;
-		spin_lock_irq (&instance->receive_lock);
-		list_for_each (pos, &instance->spare_receivers) {
-			++count;
-			DEBUG_ON (count > num_rcv_urbs);
-		}
-		spin_unlock_irq (&instance->receive_lock);
-
-		dbg ("udsl_usb_disconnect: found %u spare receivers", count);
-
-		if (count == num_rcv_urbs)
-			break;
-
-		set_current_state (TASK_RUNNING);
-		schedule ();
-	} while (1);
+		usb_kill_urb (instance->receivers [i].urb);
 
 	/* no need to take the spinlock */
 	INIT_LIST_HEAD (&instance->filled_receive_buffers);
@@ -1275,27 +1253,7 @@ static void udsl_usb_disconnect (struct usb_interface *intf)
 	tasklet_disable (&instance->send_tasklet);
 
 	for (i = 0; i < num_snd_urbs; i++)
-		if ((result = usb_unlink_urb (instance->senders [i].urb)) < 0)
-			dbg ("udsl_usb_disconnect: usb_unlink_urb on send urb %d returned %d!", i, result);
-
-	/* wait for completion handlers to finish */
-	do {
-		count = 0;
-		spin_lock_irq (&instance->send_lock);
-		list_for_each (pos, &instance->spare_senders) {
-			++count;
-			DEBUG_ON (count > num_snd_urbs);
-		}
-		spin_unlock_irq (&instance->send_lock);
-
-		dbg ("udsl_usb_disconnect: found %u spare senders", count);
-
-		if (count == num_snd_urbs)
-			break;
-
-		set_current_state (TASK_RUNNING);
-		schedule ();
-	} while (1);
+		usb_kill_urb (instance->senders [i].urb);
 
 	/* no need to take the spinlock */
 	INIT_LIST_HEAD (&instance->spare_senders);