Merge tag 'for-usb-linus-2012-02-14' of git://git.kernel.org/pub/scm/linux/kernel/git/sarah/xhci into usb-linus

xHCI bug fix for broken BIOS on some Intel systems.

Happy Valentine's Day!  Your present is a working xHCI driver under some
Intel systems with buggy BIOSes that don't provide a legacy PCI IRQ line
for the USB 3.0 host.

Please queue for 3.3 and stable to share the love!

1 files changed, 4 insertions, 2 deletions

diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c
index eb19cba34ac9..e1282328fc27 100644
--- a/drivers/usb/core/hcd.c
+++ b/drivers/usb/core/hcd.c
@@ -2447,8 +2447,10 @@ int usb_add_hcd(struct usb_hcd *hcd,
                         && device_can_wakeup(&hcd->self.root_hub->dev))
                 dev_dbg(hcd->self.controller, "supports USB remote wakeup\n");
 
-        /* enable irqs just before we start the controller */
-        if (usb_hcd_is_primary_hcd(hcd)) {
+        /* enable irqs just before we start the controller,
+         * if the BIOS provides legacy PCI irqs.
+         */
+        if (usb_hcd_is_primary_hcd(hcd) && irqnum) {
                 retval = usb_hcd_request_irqs(hcd, irqnum, irqflags);
                 if (retval)
                         goto err_request_irq;