3.16.55-rc1 review patch. If anyone has any objections, please let me know.
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From: Mathias Nyman mathias.nyman@linux.intel.com
commit e4ec40ec4b260efcca15089de4285a0a3411259b upstream.
xHC can generate two events for a short transfer if the short TRB and last TRB in the TD are not the same TRB.
The driver will handle the TD after the first short event, and remove it from its internal list. Driver then incorrectly prints a warning for the second event:
"WARN Event TRB for slot x ep y with no TDs queued"
Fix this by not printing a warning if we get a event on a empty list if the previous event was a short event.
Signed-off-by: Mathias Nyman mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings ben@decadent.org.uk --- drivers/usb/host/xhci-ring.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-)
--- a/drivers/usb/host/xhci-ring.c +++ b/drivers/usb/host/xhci-ring.c @@ -2442,12 +2442,16 @@ static int handle_tx_event(struct xhci_h */ if (list_empty(&ep_ring->td_list)) { /* - * A stopped endpoint may generate an extra completion - * event if the device was suspended. Don't print - * warnings. + * Don't print wanings if it's due to a stopped endpoint + * generating an extra completion event if the device + * was suspended. Or, a event for the last TRB of a + * short TD we already got a short event for. + * The short TD is already removed from the TD list. */ + if (!(trb_comp_code == COMP_STOP || - trb_comp_code == COMP_STOP_INVAL)) { + trb_comp_code == COMP_STOP_INVAL || + ep_ring->last_td_was_short)) { xhci_warn(xhci, "WARN Event TRB for slot %d ep %d with no TDs queued?\n", TRB_TO_SLOT_ID(le32_to_cpu(event->flags)), ep_index);