Merge tag 'for-usb-linus-2013-07-25' of git://git.kernel.org/pub/scm/linux/kernel/git/sarah/xhci into usb-linus

Sarah writes:

xhci: Bug fixes, now with more tags!

Hi Greg,

Here's five bug fixes for 3.12.

The three patches are marked for stable.  Two fix NULL pointer dereferences.
The third marked for stable suppresses some serious log spam from unnecessary
xHCI driver warnings, whenever an isochronous short packet happens on an xHCI
1.0 host.

The other two patches fix build warnings.

Sarah Sharp

4 files changed, 14 insertions, 7 deletions

diff --git a/drivers/usb/host/pci-quirks.h b/drivers/usb/host/pci-quirks.h
index 4b8a2092432f..978c849f9c9a 100644
--- a/drivers/usb/host/pci-quirks.h
+++ b/drivers/usb/host/pci-quirks.h
@@ -13,6 +13,7 @@ void usb_enable_xhci_ports(struct pci_dev *xhci_pdev);
 void usb_disable_xhci_ports(struct pci_dev *xhci_pdev);
 void sb800_prefetch(struct device *dev, int on);
 #else
+struct pci_dev;
 static inline void usb_amd_quirk_pll_disable(void) {}
 static inline void usb_amd_quirk_pll_enable(void) {}
 static inline void usb_amd_dev_put(void) {}
diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c
index cc24e39b97d5..f00cb203faea 100644
--- a/drivers/usb/host/xhci-pci.c
+++ b/drivers/usb/host/xhci-pci.c
@@ -93,7 +93,6 @@ static void xhci_pci_quirks(struct device *dev, struct xhci_hcd *xhci)
         }
         if (pdev->vendor == PCI_VENDOR_ID_INTEL &&
                         pdev->device == PCI_DEVICE_ID_INTEL_PANTHERPOINT_XHCI) {
-                xhci->quirks |= XHCI_SPURIOUS_SUCCESS;
                 xhci->quirks |= XHCI_EP_LIMIT_QUIRK;
                 xhci->limit_active_eps = 64;
                 xhci->quirks |= XHCI_SW_BW_CHECKING;
diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index 1e57eafa6910..5b08cd85f8e7 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -434,7 +434,7 @@ static void ring_doorbell_for_active_rings(struct xhci_hcd *xhci,
 
         /* A ring has pending URBs if its TD list is not empty */
         if (!(ep->ep_state & EP_HAS_STREAMS)) {
-                if (!(list_empty(&ep->ring->td_list)))
+                if (ep->ring && !(list_empty(&ep->ring->td_list)))
                         xhci_ring_ep_doorbell(xhci, slot_id, ep_index, 0);
                 return;
         }
diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 2c49f00260ca..41eb4fc33453 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -329,7 +329,7 @@ static void xhci_cleanup_msix(struct xhci_hcd *xhci)
         return;
 }
 
-static void xhci_msix_sync_irqs(struct xhci_hcd *xhci)
+static void __maybe_unused xhci_msix_sync_irqs(struct xhci_hcd *xhci)
 {
         int i;
 
@@ -1181,9 +1181,6 @@ static int xhci_check_args(struct usb_hcd *hcd, struct usb_device *udev,
         }
 
         xhci = hcd_to_xhci(hcd);
-        if (xhci->xhc_state & XHCI_STATE_HALTED)
-                return -ENODEV;
-
         if (check_virt_dev) {
                 if (!udev->slot_id || !xhci->devs[udev->slot_id]) {
                         printk(KERN_DEBUG "xHCI %s called with unaddressed "
@@ -1199,6 +1196,9 @@ static int xhci_check_args(struct usb_hcd *hcd, struct usb_device *udev,
                 }
         }
 
+        if (xhci->xhc_state & XHCI_STATE_HALTED)
+                return -ENODEV;
+
         return 1;
 }
 
@@ -3898,7 +3898,7 @@ int xhci_find_raw_port_number(struct usb_hcd *hcd, int port1)
  * Issue an Evaluate Context command to change the Maximum Exit Latency in the
  * slot context.  If that succeeds, store the new MEL in the xhci_virt_device.
  */
-static int xhci_change_max_exit_latency(struct xhci_hcd *xhci,
+static int __maybe_unused xhci_change_max_exit_latency(struct xhci_hcd *xhci,
                         struct usb_device *udev, u16 max_exit_latency)
 {
         struct xhci_virt_device *virt_dev;
@@ -4892,6 +4892,13 @@ int xhci_gen_setup(struct usb_hcd *hcd, xhci_get_quirks_t get_quirks)
 
         get_quirks(dev, xhci);
 
+        /* In xhci controllers which follow xhci 1.0 spec gives a spurious
+         * success event after a short transfer. This quirk will ignore such
+         * spurious event.
+         */
+        if (xhci->hci_version > 0x96)
+                xhci->quirks |= XHCI_SPURIOUS_SUCCESS;
+
         /* Make sure the HC is halted. */
         retval = xhci_halt(xhci);
         if (retval)