rt2x00: Don't perform watchdog checks on empty queue

The currently used watchdog functions cannot be applied
to empty queues.

Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
Acked-by: Helmut Schaa <helmut.schaa@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 6 insertions, 4 deletions

diff --git a/drivers/net/wireless/rt2x00/rt2x00usb.c b/drivers/net/wireless/rt2x00/rt2x00usb.c
index 769c53451b21..89d77f55d76c 100644
--- a/drivers/net/wireless/rt2x00/rt2x00usb.c
+++ b/drivers/net/wireless/rt2x00/rt2x00usb.c
@@ -363,10 +363,12 @@ void rt2x00usb_watchdog(struct rt2x00_dev *rt2x00dev)
         struct data_queue *queue;
 
         tx_queue_for_each(rt2x00dev, queue) {
-                if (rt2x00queue_dma_timeout(queue))
-                        rt2x00usb_watchdog_tx_dma(queue);
-                if (rt2x00queue_timeout(queue))
-                        rt2x00usb_watchdog_tx_status(queue);
+                if (!rt2x00queue_empty(queue)) {
+                        if (rt2x00queue_dma_timeout(queue))
+                                rt2x00usb_watchdog_tx_dma(queue);
+                        if (rt2x00queue_timeout(queue))
+                                rt2x00usb_watchdog_tx_status(queue);
+                }
         }
 }
 EXPORT_SYMBOL_GPL(rt2x00usb_watchdog);