xhci: Disable MSI for some Fresco Logic hosts.

commit f5182b4155b9d686c5540a6822486400e34ddd98 upstream.

Some Fresco Logic hosts, including those found in the AUAU N533V laptop,
advertise MSI, but fail to actually generate MSI interrupts.  Add a new
xHCI quirk to skip MSI enabling for the Fresco Logic host controllers.
Fresco Logic confirms that all chips with PCI vendor ID 0x1b73 and device
ID 0x1000, regardless of PCI revision ID, do not support MSI.

This should be backported to stable kernels as far back as 2.6.36, which
was the first kernel to support MSI on xHCI hosts.

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Reported-by: Sergey Galanov <sergey.e.galanov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c
index a10494c2f3c7749a83fe52b2479c469da47e9d0e..4940717029e94f7d8eab378829866c501b0e4dd3 100644 (file)
--- a/drivers/usb/host/xhci-pci.c
+++ b/drivers/usb/host/xhci-pci.c
@@ -105,12 +105,22 @@ static int xhci_pci_setup(struct usb_hcd *hcd)
 
        /* Look for vendor-specific quirks */
        if (pdev->vendor == PCI_VENDOR_ID_FRESCO_LOGIC &&
-                       pdev->device == PCI_DEVICE_ID_FRESCO_LOGIC_PDK &&
-                       pdev->revision == 0x0) {
+                       pdev->device == PCI_DEVICE_ID_FRESCO_LOGIC_PDK) {
+               if (pdev->revision == 0x0) {
                        xhci->quirks |= XHCI_RESET_EP_QUIRK;
                        xhci_dbg(xhci, "QUIRK: Fresco Logic xHC needs configure"
                                        " endpoint cmd after reset endpoint\n");
+               }
+               /* Fresco Logic confirms: all revisions of this chip do not
+                * support MSI, even though some of them claim to in their PCI
+                * capabilities.
+                */
+               xhci->quirks |= XHCI_BROKEN_MSI;
+               xhci_dbg(xhci, "QUIRK: Fresco Logic revision %u "
+                               "has broken MSI implementation\n",
+                               pdev->revision);
        }
+
        if (pdev->vendor == PCI_VENDOR_ID_NEC)
                xhci->quirks |= XHCI_NEC_HOST;
 

diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index d1f074fa821be14786a511255c78bd0dd4ee5799..e5c48615150f7ace7504a9f4682986ca7cc0bd8a 100644 (file)
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -430,12 +430,19 @@ int xhci_run(struct usb_hcd *hcd)
                free_irq(hcd->irq, hcd);
        hcd->irq = -1;
 
+       /* Some Fresco Logic host controllers advertise MSI, but fail to
+        * generate interrupts.  Don't even try to enable MSI.
+        */
+       if (xhci->quirks & XHCI_BROKEN_MSI)
+               goto legacy_irq;
+
        ret = xhci_setup_msix(xhci);
        if (ret)
                /* fall back to msi*/
                ret = xhci_setup_msi(xhci);
 
        if (ret) {
+legacy_irq:
                /* fall back to legacy interrupt*/
                ret = request_irq(pdev->irq, &usb_hcd_irq, IRQF_SHARED,
                                        hcd->irq_descr, hcd);

diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index 507a50f72e5efe51330f5c30e9ae41ff40176e10..fb85ce3269a18a66888eb3fc6b1ab0cddb232533 100644 (file)
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -1286,6 +1286,7 @@ struct xhci_hcd {
 #define XHCI_RESET_EP_QUIRK    (1 << 1)
 #define XHCI_NEC_HOST          (1 << 2)
 #define XHCI_AMD_PLL_FIX       (1 << 3)
+#define XHCI_BROKEN_MSI                (1 << 6)
        /* There are two roothubs to keep track of bus suspend info for */
        struct xhci_bus_state   bus_state[2];
        /* Is each xHCI roothub port a USB 3.0, USB 2.0, or USB 1.1 port? */