tree 8da83468bfe35444f868fd835b4c36bfb3fefae5
parent 0ef6e894dfab96967e4d27d5fc17910257edbb72
author Mathias Nyman <mathias.nyman@linux.intel.com> 1416302832 +0200
committer Matthias Kaehlcke <mka@google.com> 1433366110 -0700

USB: xhci: Reset a halted endpoint immediately when we encounter a stall.

commit 8e71a322fdb127814bcba423a512914ca5bc6cf5 upstream.

If a device is halted and reuturns a STALL, then the halted endpoint
needs to be cleared both on the host and device side. The host
side halt is cleared by issueing a xhci reset endpoint command. The device side
is cleared with a ClearFeature(ENDPOINT_HALT) request, which should
be issued by the device driver if a URB reruen -EPIPE.

Previously we cleared the host side halt after the device side was cleared.
To make sure the host side halt is cleared in time we want to issue the
reset endpoint command immedialtely when a STALL status is encountered.

Otherwise we end up not following the specs and not returning -EPIPE
several times in a row when trying to transfer data to a halted endpoint.

Fixes: bcef3fd (USB: xhci: Handle errors that cause endpoint halts.)
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>
[bwh: Backported to 3.2: xhci_endpoint_reset() looked a little different]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>