USB: address FIXME in usbnet w.r.t drivers claiming multiple interfaces

This fixes the issue of drivers claiming multiple interfaces. Operations
are stopped as soon as an interface is suspend and resumed only as
all interfaces have been resumed.

Signed-off-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

2 files changed, 16 insertions, 10 deletions

diff --git a/drivers/net/usb/usbnet.c b/drivers/net/usb/usbnet.c
index f9cd42d058b0..5b16d9a1269a 100644
--- a/drivers/net/usb/usbnet.c
+++ b/drivers/net/usb/usbnet.c
@@ -1252,20 +1252,23 @@ EXPORT_SYMBOL_GPL(usbnet_probe);
 
 /*-------------------------------------------------------------------------*/
 
-/* FIXME these suspend/resume methods assume non-CDC style
- * devices, with only one interface.
+/*
+ * suspend the whole driver as soon as the first interface is suspended
+ * resume only when the last interface is resumed
  */
 
 int usbnet_suspend (struct usb_interface *intf, pm_message_t message)
 {
         struct usbnet           *dev = usb_get_intfdata(intf);
 
-        /* accelerate emptying of the rx and queues, to avoid
-         * having everything error out.
-         */
-        netif_device_detach (dev->net);
-        (void) unlink_urbs (dev, &dev->rxq);
-        (void) unlink_urbs (dev, &dev->txq);
+        if (!dev->suspend_count++) {
+                /* accelerate emptying of the rx and queues, to avoid
+                 * having everything error out.
+                 */
+                netif_device_detach (dev->net);
+                (void) unlink_urbs (dev, &dev->rxq);
+                (void) unlink_urbs (dev, &dev->txq);
+        }
         return 0;
 }
 EXPORT_SYMBOL_GPL(usbnet_suspend);
@@ -1274,8 +1277,10 @@ int usbnet_resume (struct usb_interface *intf)
 {
         struct usbnet           *dev = usb_get_intfdata(intf);
 
-        netif_device_attach (dev->net);
-        tasklet_schedule (&dev->bh);
+        if (!--dev->suspend_count) {
+                netif_device_attach (dev->net);
+                tasklet_schedule (&dev->bh);
+        }
         return 0;
 }
 EXPORT_SYMBOL_GPL(usbnet_resume);
diff --git a/drivers/net/usb/usbnet.h b/drivers/net/usb/usbnet.h
index 82db5a8e528e..a3f8b9e7bc00 100644
--- a/drivers/net/usb/usbnet.h
+++ b/drivers/net/usb/usbnet.h
@@ -32,6 +32,7 @@ struct usbnet {
         const char              *driver_name;
         wait_queue_head_t       *wait;
         struct mutex            phy_mutex;
+        unsigned char           suspend_count;
 
         /* i/o info: pipes etc */
         unsigned                in, out;