Commit a6829706 authored by Felipe Balbi's avatar Felipe Balbi
Browse files

usb: dwc3: ep0: add handling for unaligned OUT transfers 



In case we have transfers which aren't aligned
to wMaxPacketSize, we need to be careful with
how we start the transfer with the HW. OUT
transfers _must_ be aligned with wMaxPacketSize
and in order to guarantee that, we use a bounce
buffer.

Signed-off-by: default avatarFelipe Balbi <balbi@ti.com>
parent 5812b1c2

drivers/usb/dwc3/ep0.c

+32 −5
Original line number Diff line number Diff line
@@ -185,10 +185,29 @@ static int __dwc3_gadget_ep0_queue(struct dwc3_ep *dep, 
	req->epnum		= dep->number;



	list_add_tail(&req->list, &dep->request_list);

	if (req->request.length == 0) {

		ret = dwc3_ep0_start_trans(dwc, dep->number,

				dwc->ctrl_req_addr, 0);

	} else if ((req->request.length % dep->endpoint.maxpacket)

			&& (dep->number == 0)) {

		dwc->ep0_bounced = true;



		WARN_ON(req->request.length > dep->endpoint.maxpacket);



		/*

		 * REVISIT in case request length is bigger than EP0

		 * wMaxPacketSize, we will need two chained TRBs to handle

		 * the transfer.

		 */

		ret = dwc3_ep0_start_trans(dwc, dep->number,

				dwc->ep0_bounce_addr, dep->endpoint.maxpacket);

	} else {

		dwc3_map_buffer_to_dma(req);



	ret = dwc3_ep0_start_trans(dwc, dep->number, req->request.dma,

			req->request.length);

		ret = dwc3_ep0_start_trans(dwc, dep->number,

				req->request.dma, req->request.length);

	}



	if (ret < 0) {

		list_del(&req->list);

		dwc3_unmap_buffer_from_dma(req);
@@ -655,8 +674,16 @@ static void dwc3_ep0_complete_data(struct dwc3 *dwc, 


	dwc3_trb_to_nat(dwc->ep0_trb, &trb);



	if (dwc->ep0_bounced) {

		struct dwc3_ep	*ep0 = dwc->eps[0];



		transferred = min(ur->length, dep->endpoint.maxpacket - trb.length);

		memcpy(ur->buf, dwc->ep0_bounce, transferred);

		dwc->ep0_bounced = false;

	} else {

		transferred = ur->length - trb.length;

		ur->actual += transferred;

	}



	if ((epnum & 1) && ur->actual < ur->length) {

		/* for some reason we did not get everything out */