xhci: Fix halted endpoint at stop endpoint command completion

xhci 4.6.9: "A busy endpoint may asynchronously transition from the
Running to the Halted or Error state due to error conditions detected
while processing TRBs. A possible race condition may occur if software,
thinking an endpoint is in the running state, issues a Stop Endpoint
Command, however at the same time the xHC asynchronously transitions
the endpoint to the Halted or Error state. In this case, a Context
State Error may be generated for the command completion. Software
may verify that this case occurred by inspecting the EP State for
Halted or Error when a Stop Endpoint Command results in a Context
State Error."

Halted endpoints were not detected or handled at all in the stop endpoint
completion handler. A set TR Deq ptr command was bluntly queued instead
of resetting the endpoint first. The set TR Deq command would fail with
a context state error.

Fix this case by resetting the halted endpoint first to get it to a
stopped state instead of the halted (error) state.
Handle cancelled TDs once endpoint reset completes,
invalidating cancelled TDs on ring either by turning them to no-op,
or in case ring stopped on cancelled TD then move hardware dequeue pointer
past it, which will clear the cancelled TD from hw cache, and make sure
HW does not process it

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20210129130044.206855-23-mathias.nyman@linux.intel.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>