The zero-length packet is the sendor tells the receiver that there is no more data, so it is only needed at the TX side. Signed-off-by: Peter Chen <peter.chen@xxxxxxxxxxxxx> --- drivers/usb/chipidea/udc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/usb/chipidea/udc.c b/drivers/usb/chipidea/udc.c index 06b7224..51e66a1 100644 --- a/drivers/usb/chipidea/udc.c +++ b/drivers/usb/chipidea/udc.c @@ -445,7 +445,7 @@ static int _hardware_enqueue(struct ci_hw_ep *hwep, struct ci_hw_req *hwreq) rest -= count; } - if (hwreq->req.zero && hwreq->req.length + if (hwreq->req.zero && hwreq->req.length && hwep->dir == TX && (hwreq->req.length % hwep->ep.maxpacket == 0)) add_td_to_list(hwep, hwreq, 0); -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html