USB: EHCI: remove PCI assumption

This patch (as1405) fixes a small bug in ehci-hcd's isochronous
scheduler.  Not all EHCI controllers are PCI, and the code shouldn't
assume that they are.  Instead, introduce a special flag for
controllers which need to delay iso scheduling for full-speed devices
beyond the scheduling threshold.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
CC: Sarah Sharp <sarah.a.sharp@linux.intel.com>
CC: David Brownell <david-b@pacbell.net>
CC: stable <stable@kernel.org>
Acked-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>

3 files changed, 6 insertions, 6 deletions

diff --git a/drivers/usb/host/ehci-pci.c b/drivers/usb/host/ehci-pci.c
index f555e4f35a04..58b72d741d93 100644
--- a/drivers/usb/host/ehci-pci.c
+++ b/drivers/usb/host/ehci-pci.c
@@ -114,6 +114,7 @@ static int ehci_pci_setup(struct usb_hcd *hcd)
                 break;
         case PCI_VENDOR_ID_INTEL:
                 ehci->need_io_watchdog = 0;
+                ehci->fs_i_thresh = 1;
                 if (pdev->device == 0x27cc) {
                         ehci->broken_periodic = 1;
                         ehci_info(ehci, "using broken periodic workaround\n");
diff --git a/drivers/usb/host/ehci-sched.c b/drivers/usb/host/ehci-sched.c
index d640346f9b56..efadced4ae67 100644
--- a/drivers/usb/host/ehci-sched.c
+++ b/drivers/usb/host/ehci-sched.c
@@ -1399,7 +1399,6 @@ iso_stream_schedule (
         int                     status;
         unsigned                mod = ehci->periodic_size << 3;
         struct ehci_iso_sched   *sched = urb->hcpriv;
-        struct pci_dev          *pdev;
 
         if (sched->span > (mod - SCHEDULE_SLOP)) {
                 ehci_dbg (ehci, "iso request %p too long\n", urb);
@@ -1426,15 +1425,14 @@ iso_stream_schedule (
          * slot in the schedule, implicitly assuming URB_ISO_ASAP.
          */
         if (likely (!list_empty (&stream->td_list))) {
-                pdev = to_pci_dev(ehci_to_hcd(ehci)->self.controller);
                 start = stream->next_uframe;
 
                 /* For high speed devices, allow scheduling within the
-                 * isochronous scheduling threshold.  For full speed devices,
-                 * don't. (Work around for Intel ICH9 bug.)
+                 * isochronous scheduling threshold.  For full speed devices
+                 * and Intel PCI-based controllers, don't (work around for
+                 * Intel ICH9 bug).
                  */
-                if (!stream->highspeed &&
-                                pdev->vendor == PCI_VENDOR_ID_INTEL)
+                if (!stream->highspeed && ehci->fs_i_thresh)
                         next = now + ehci->i_thresh;
                 else
                         next = now;
diff --git a/drivers/usb/host/ehci.h b/drivers/usb/host/ehci.h
index a4a63ce290e9..2c050efd1deb 100644
--- a/drivers/usb/host/ehci.h
+++ b/drivers/usb/host/ehci.h
@@ -130,6 +130,7 @@ struct ehci_hcd {			/* one per controller */
         unsigned                has_amcc_usb23:1;
         unsigned                need_io_watchdog:1;
         unsigned                broken_periodic:1;
+        unsigned                fs_i_thresh:1;  /* Intel iso scheduling */
 
         /* required for usb32 quirk */
         #define OHCI_CTRL_HCFS          (3 << 6)