tree 3deb2b83974a9cfa61def8f8ab248cafbbb9809f
parent f9dc68fe7ad390428c6bc5d7ff582cdb5d92fcb8
author Sarah Sharp <sarah.a.sharp@linux.intel.com> 1248721395 -0700
committer Greg Kroah-Hartman <gregkh@suse.de> 1248816671 -0700

USB: xhci: Deal with stalled endpoints.

When an endpoint on a device under an xHCI host controller stalls, the
host controller driver must let the hardware know that the USB core has
successfully cleared the halt condition.  The HCD submits a Reset Endpoint
Command, which will clear the toggle bit for USB 2.0 devices, and set the
sequence number to zero for USB 3.0 devices.

The xHCI urb_enqueue will accept new URBs while the endpoint is halted,
and will queue them to the hardware rings.  However, the endpoint doorbell
will not be rung until the Reset Endpoint Command completes.

Don't queue a reset endpoint command for root hubs.  khubd clears halt
conditions on the roothub during the initialization process, but the roothub
isn't a real device, so the xHCI host controller doesn't need to know about the
cleared halt.

Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>