Commit cb1b3997 authored by Thinh Nguyen's avatar Thinh Nguyen Committed by Felipe Balbi
Browse files

usb: dwc3: gadget: Refactor preparing last TRBs 



There are a lot of common codes for preparing SG and linear TRBs.
Refactor them for easier read.

Signed-off-by: default avatarThinh Nguyen <Thinh.Nguyen@synopsys.com>
Signed-off-by: default avatarFelipe Balbi <balbi@kernel.org>
parent 30892cba

drivers/usb/dwc3/gadget.c

+48 −81
Original line number Diff line number Diff line
@@ -1094,6 +1094,47 @@ static void dwc3_prepare_one_trb(struct dwc3_ep *dep, 
			stream_id, short_not_ok, no_interrupt, is_last);

}



/**

 * dwc3_prepare_last_sg - prepare TRBs for the last SG entry

 * @dep: The endpoint that the request belongs to

 * @req: The request to prepare

 * @entry_length: The last SG entry size

 * @node: Indicates whether this is not the first entry (for isoc only)

 *

 * Return the number of TRBs prepared.

 */

static int dwc3_prepare_last_sg(struct dwc3_ep *dep,

		struct dwc3_request *req, unsigned int entry_length,

		unsigned int node)

{

	unsigned int maxp = usb_endpoint_maxp(dep->endpoint.desc);

	unsigned int rem = req->request.length % maxp;

	unsigned int num_trbs = 1;



	if ((req->request.length && req->request.zero && !rem &&

			!usb_endpoint_xfer_isoc(dep->endpoint.desc)) ||

			(!req->direction && rem))

		num_trbs++;



	if (dwc3_calc_trbs_left(dep) < num_trbs)

		return 0;



	req->needs_extra_trb = num_trbs > 1;



	/* Prepare a normal TRB */

	if (req->direction || req->request.length)

		dwc3_prepare_one_trb(dep, req, entry_length,

				req->needs_extra_trb, node, false);



	/* Prepare extra TRBs for ZLP and MPS OUT transfer alignment */

	if ((!req->direction && !req->request.length) || req->needs_extra_trb)

		dwc3_prepare_one_trb(dep, req,

				req->direction ? 0 : maxp - rem,

				false, 1, true);



	return num_trbs;

}



static int dwc3_prepare_one_trb_sg(struct dwc3_ep *dep,

		struct dwc3_request *req)

{
@@ -1101,8 +1142,6 @@ static int dwc3_prepare_one_trb_sg(struct dwc3_ep *dep, 
	struct scatterlist *s;

	int		i;

	unsigned int length = req->request.length;

	unsigned int maxp = usb_endpoint_maxp(dep->endpoint.desc);

	unsigned int rem = length % maxp;

	unsigned int remaining = req->request.num_mapped_sgs

		- req->num_queued_sgs;

	unsigned int num_trbs = req->num_trbs;
@@ -1116,7 +1155,7 @@ static int dwc3_prepare_one_trb_sg(struct dwc3_ep *dep, 


	for_each_sg(sg, s, remaining, i) {

		unsigned int trb_length;

		unsigned int chain = true;

		bool last_sg = false;



		trb_length = min_t(unsigned int, length, sg_dma_len(s));
@@ -1130,45 +1169,16 @@ static int dwc3_prepare_one_trb_sg(struct dwc3_ep *dep, 
		 * mapped sg.

		 */

		if ((i == remaining - 1) || !length)

			chain = false;

			last_sg = true;



		if (!dwc3_calc_trbs_left(dep))

			break;



		if (rem && usb_endpoint_dir_out(dep->endpoint.desc) && !chain) {

			/* prepare normal TRB */

			if (req->request.length) {

				if (dwc3_calc_trbs_left(dep) < 2)

		if (last_sg) {

			if (!dwc3_prepare_last_sg(dep, req, trb_length, i))

				goto out;



				req->needs_extra_trb = true;

				dwc3_prepare_one_trb(dep, req, trb_length,

					true, i, false);

			}



			/* Now prepare one extra TRB to align transfer size */

			dwc3_prepare_one_trb(dep, req, maxp - rem,

					false, 1, true);

		} else if (req->request.zero && req->request.length &&

			   !usb_endpoint_xfer_isoc(dep->endpoint.desc) &&

			   !rem && !chain) {



			if (dwc3_calc_trbs_left(dep) < 2)

				goto out;



			req->needs_extra_trb = true;



			/* Prepare normal TRB */

			dwc3_prepare_one_trb(dep, req, trb_length,

					true, i, false);



			/* Prepare one extra TRB to handle ZLP */

			dwc3_prepare_one_trb(dep, req,

					req->direction ? 0 : maxp,

					false, 1, true);

		} else {

			dwc3_prepare_one_trb(dep, req, trb_length,

					chain, i, false);

			dwc3_prepare_one_trb(dep, req, trb_length, 1, i, false);

		}



		/*
@@ -1178,7 +1188,7 @@ static int dwc3_prepare_one_trb_sg(struct dwc3_ep *dep, 
		 * we have free trbs we can continue queuing from where we

		 * previously stopped

		 */

		if (chain)

		if (!last_sg)

			req->start_sg = sg_next(s);



		req->num_queued_sgs++;
@@ -1224,50 +1234,7 @@ static int dwc3_prepare_one_trb_sg(struct dwc3_ep *dep, 
static int dwc3_prepare_one_trb_linear(struct dwc3_ep *dep,

		struct dwc3_request *req)

{

	unsigned int length = req->request.length;

	unsigned int maxp = usb_endpoint_maxp(dep->endpoint.desc);

	unsigned int rem = length % maxp;

	unsigned int num_trbs = req->num_trbs;



	if (!dwc3_calc_trbs_left(dep))

		goto out;



	if ((!length || rem) && usb_endpoint_dir_out(dep->endpoint.desc)) {

		/* prepare normal TRB */

		if (req->request.length) {

			if (dwc3_calc_trbs_left(dep) < 2)

				goto out;



			req->needs_extra_trb = true;

			dwc3_prepare_one_trb(dep, req, length, true, 0, false);

		}



		/* Now prepare one extra TRB to align transfer size */

		dwc3_prepare_one_trb(dep, req, maxp - rem, false, 1, true);

	} else if (req->request.zero && req->request.length &&

		   !usb_endpoint_xfer_isoc(dep->endpoint.desc) &&

		   (IS_ALIGNED(req->request.length, maxp))) {



		if (dwc3_calc_trbs_left(dep) < 2)

			goto out;



		req->needs_extra_trb = true;



		/* prepare normal TRB */

		dwc3_prepare_one_trb(dep, req, length, true, 0, false);



		/* Prepare one extra TRB to handle ZLP */

		dwc3_prepare_one_trb(dep, req, req->direction ? 0 : maxp,

				false, 1, true);

	} else {

		if (!dwc3_calc_trbs_left(dep))

			goto out;



		dwc3_prepare_one_trb(dep, req, length, false, 0, false);

	}



out:

	return req->num_trbs - num_trbs;

	return dwc3_prepare_last_sg(dep, req, req->request.length, 0);

}



/*