diff --git a/drivers/pci/setup-irq.c b/drivers/pci/setup-irq.c
index a251289c9958e846ebc50d45254ec2bea6b14cf5..568f1877315c5532d39052e4e615f1304a48cb93 100644
--- a/drivers/pci/setup-irq.c
+++ b/drivers/pci/setup-irq.c
@@ -24,7 +24,7 @@ pdev_fixup_irq(struct pci_dev *dev,
 	       int (*map_irq)(struct pci_dev *, u8, u8))
 {
 	u8 pin, slot;
-	int irq;
+	int irq = 0;
 
 	/* If this device is not on the primary bus, we need to figure out
 	   which interrupt pin it will come in on.   We know which slot it
@@ -33,16 +33,18 @@ pdev_fixup_irq(struct pci_dev *dev,
 	   apply the swizzle function.  */
 
 	pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &pin);
-	/* Cope with 0 and illegal. */
-	if (pin == 0 || pin > 4)
+	/* Cope with illegal. */
+	if (pin > 4)
 		pin = 1;
 
-	/* Follow the chain of bridges, swizzling as we go.  */
-	slot = (*swizzle)(dev, &pin);
+	if (pin != 0) {
+		/* Follow the chain of bridges, swizzling as we go.  */
+		slot = (*swizzle)(dev, &pin);
 
-	irq = (*map_irq)(dev, slot, pin);
-	if (irq == -1)
-		irq = 0;
+		irq = (*map_irq)(dev, slot, pin);
+		if (irq == -1)
+			irq = 0;
+	}
 	dev->irq = irq;
 
 	pr_debug("PCI: fixup irq: (%s) got %d\n",