USB: xhci: don't start a halted endpoint before its new dequeue is set
authorMathias Nyman <mathias.nyman@linux.intel.com>
Tue, 18 Nov 2014 09:27:11 +0000 (11:27 +0200)
committerBen Hutchings <ben@decadent.org.uk>
Sun, 14 Dec 2014 16:23:59 +0000 (16:23 +0000)
commitaba14f8ea6cb108e0ed1e938f24d26cd29bd02b4
treecb57387d4699adebc6fadf85538dc360bedccaba
parent40f674b67601ebf7772372caea07824e911e5ac8
USB: xhci: don't start a halted endpoint before its new dequeue is set

commit c3492dbfa1050debf23a5b5cd2bc7514c5b37896 upstream.

A halted endpoint ring must first be reset, then move the ring
dequeue pointer past the problematic TRB. If we start the ring too
early after reset, but before moving the dequeue pointer we
will end up executing the same problematic TRB again.

As we always issue a set transfer dequeue command after a reset
endpoint command we can skip starting endpoint rings at reset endpoint
command completion.

Without this fix we end up trying to handle the same faulty TD for
contol endpoints. causing timeout, and failing testusb ctrl_out write
tests.

Fixes: e9df17e (USB: xhci: Correct assumptions about number of rings per endpoint.)
Tested-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
drivers/usb/host/xhci-ring.c