diff --git a/drivers/net/sonic.c b/drivers/net/sonic.c
index cfece96..ed7aa0a 100644
--- a/drivers/net/sonic.c
+++ b/drivers/net/sonic.c
@@ -295,15 +295,10 @@
  */
 static irqreturn_t sonic_interrupt(int irq, void *dev_id)
 {
-	struct net_device *dev = (struct net_device *) dev_id;
+	struct net_device *dev = dev_id;
 	struct sonic_local *lp = netdev_priv(dev);
 	int status;
 
-	if (dev == NULL) {
-		printk(KERN_ERR "sonic_interrupt: irq %d for unknown device.\n", irq);
-		return IRQ_NONE;
-	}
-
 	if (!(status = SONIC_READ(SONIC_ISR) & SONIC_IMR_DEFAULT))
 		return IRQ_NONE;