diff --git a/drivers/acpi/pci_irq.c b/drivers/acpi/pci_irq.c
index b0a71ecee6820c198feb628184c90bf0b54ebfe9..e4804fb05e233d8dae18aacce47835a06dca16ec 100644
--- a/drivers/acpi/pci_irq.c
+++ b/drivers/acpi/pci_irq.c
@@ -401,11 +401,13 @@ int acpi_pci_irq_enable(struct pci_dev *dev)
 	 * driver reported one, then use it. Exit in any case.
 	 */
 	if (gsi < 0) {
+		u32 dev_gsi;
 		dev_warn(&dev->dev, "PCI INT %c: no GSI", pin_name(pin));
 		/* Interrupt Line values above 0xF are forbidden */
-		if (dev->irq > 0 && (dev->irq <= 0xF)) {
-			printk(" - using IRQ %d\n", dev->irq);
-			acpi_register_gsi(&dev->dev, dev->irq,
+		if (dev->irq > 0 && (dev->irq <= 0xF) &&
+		    (acpi_isa_irq_to_gsi(dev->irq, &dev_gsi) == 0)) {
+			printk(" - using ISA IRQ %d\n", dev->irq);
+			acpi_register_gsi(&dev->dev, dev_gsi,
 					  ACPI_LEVEL_SENSITIVE,
 					  ACPI_ACTIVE_LOW);
 			return 0;