USB: Don't fail USB3 probe on missing legacy PCI IRQ.

commit 68d07f64b8a11a852d48d1b05b724c3e20c0d94b upstream.

Intel has a PCI USB xhci host controller on a new platform. It doesn't
have a line IRQ definition in BIOS.  The Linux driver refuses to
initialize this controller, but Windows works well because it only depends
on MSI.

Actually, Linux also can work for MSI.  This patch avoids the line IRQ
checking for USB3 HCDs in usb core PCI probe.  It allows the xHCI driver
to try to enable MSI or MSI-X first.  It will fail the probe if MSI
enabling failed and there's no legacy PCI IRQ.

This patch should be backported to kernels as old as 2.6.32.

Signed-off-by: Alex Shi <alex.shi@intel.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/core/hcd-pci.c b/drivers/usb/core/hcd-pci.c
index a004db35f6d0e90cced45aa9bd81ca107d2ed472..61d08ddcf888466f3e4828522d921edf5e0b11e2 100644 (file)
--- a/drivers/usb/core/hcd-pci.c
+++ b/drivers/usb/core/hcd-pci.c
@@ -187,7 +187,10 @@ int usb_hcd_pci_probe(struct pci_dev *dev, const struct pci_device_id *id)
                return -ENODEV;
        dev->current_state = PCI_D0;
 
-       if (!dev->irq) {
+       /* The xHCI driver supports MSI and MSI-X,
+        * so don't fail if the BIOS doesn't provide a legacy IRQ.
+        */
+       if (!dev->irq && (driver->flags & HCD_MASK) != HCD_USB3) {
                dev_err(&dev->dev,
                        "Found HC with no IRQ.  Check BIOS/PCI %s setup!\n",
                        pci_name(dev));

diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c
index 179e3646241dd854cba4a822c04a74978d04c8f7..8cb9304e8d4f650ebee851688fa3104a8209a738 100644 (file)
--- a/drivers/usb/core/hcd.c
+++ b/drivers/usb/core/hcd.c
@@ -2465,8 +2465,10 @@ 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;

diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index b33f0598ccfea0e2d3972b5437ef9005035049aa..034f5543b5fd1c7471ba786759bf9311f4b5f73a 100644 (file)
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -352,6 +352,11 @@ static int xhci_try_enable_msi(struct usb_hcd *hcd)
                /* hcd->irq is -1, we have MSI */
                return 0;
 
+       if (!pdev->irq) {
+               xhci_err(xhci, "No msi-x/msi found and no IRQ in BIOS\n");
+               return -EINVAL;
+       }
+
        /* fall back to legacy interrupt*/
        ret = request_irq(pdev->irq, &usb_hcd_irq, IRQF_SHARED,
                        hcd->irq_descr, hcd);