usbnet: handle PM failure gracefully

If a device fails to do remote wakeup, this is no reason
to abort an open totally. This patch just continues without
runtime PM.

Signed-off-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 9 insertions, 7 deletions

diff --git a/drivers/net/usb/usbnet.c b/drivers/net/usb/usbnet.c
index c04110ba677..50ed7ab09c9 100644
--- a/drivers/net/usb/usbnet.c
+++ b/drivers/net/usb/usbnet.c
@@ -719,7 +719,8 @@ int usbnet_stop (struct net_device *net)
         dev->flags = 0;
         del_timer_sync (&dev->delay);
         tasklet_kill (&dev->bh);
-        if (info->manage_power)
+        if (info->manage_power &&
+            !test_and_clear_bit(EVENT_NO_RUNTIME_PM, &dev->flags))
                 info->manage_power(dev, 0);
         else
                 usb_autopm_put_interface(dev->intf);
@@ -794,14 +795,14 @@ int usbnet_open (struct net_device *net)
         tasklet_schedule (&dev->bh);
         if (info->manage_power) {
                 retval = info->manage_power(dev, 1);
-                if (retval < 0)
-                        goto done_manage_power_error;
-                usb_autopm_put_interface(dev->intf);
+                if (retval < 0) {
+                        retval = 0;
+                        set_bit(EVENT_NO_RUNTIME_PM, &dev->flags);
+                } else {
+                        usb_autopm_put_interface(dev->intf);
+                }
         }
         return retval;
-
-done_manage_power_error:
-        clear_bit(EVENT_DEV_OPEN, &dev->flags);
 done:
         usb_autopm_put_interface(dev->intf);
 done_nopm:
diff --git a/include/linux/usb/usbnet.h b/include/linux/usb/usbnet.h
index 9bbeabf66c5..288b32aadab 100644
--- a/include/linux/usb/usbnet.h
+++ b/include/linux/usb/usbnet.h
@@ -69,6 +69,7 @@ struct usbnet {
 #               define EVENT_DEV_ASLEEP 6
 #               define EVENT_DEV_OPEN   7
 #               define EVENT_DEVICE_REPORT_IDLE 8
+#               define EVENT_NO_RUNTIME_PM      9
 };
 
 static inline struct usb_driver *driver_of(struct usb_interface *intf)