Basically the io watchdog is only useful for those quirk HCDs. For most
good ones, it only brings unnecessary wakeups.  At least, I know the
Intel EHCI HCDs should turn off the flag.
Signed-off-by: Alek Du <alek.du@intel.com>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
 
                switch (action) {
                case TIMER_IO_WATCHDOG:
+                       if (!ehci->need_io_watchdog)
+                               return;
                        t = EHCI_IO_JIFFIES;
                        break;
                case TIMER_ASYNC_OFF:
 
        spin_lock_init(&ehci->lock);
 
+       /*
+        * keep io watchdog by default, those good HCDs could turn off it later
+        */
+       ehci->need_io_watchdog = 1;
        init_timer(&ehci->watchdog);
        ehci->watchdog.function = ehci_watchdog;
        ehci->watchdog.data = (unsigned long) ehci;
 
                return retval;
 
        switch (pdev->vendor) {
+       case PCI_VENDOR_ID_INTEL:
+               ehci->need_io_watchdog = 0;
+               break;
        case PCI_VENDOR_ID_TDI:
                if (pdev->device == PCI_DEVICE_ID_TDI_EHCI) {
                        hcd->has_tt = 1;
 
        unsigned                big_endian_mmio:1;
        unsigned                big_endian_desc:1;
        unsigned                has_amcc_usb23:1;
+       unsigned                need_io_watchdog:1;
 
        /* required for usb32 quirk */
        #define OHCI_CTRL_HCFS          (3 << 6)