Commit c71fc37c authored by Felipe Balbi's avatar Felipe Balbi
Browse files

usb: dwc3: gadget: re-factor dwc3_prepare_trbs() 



In order to make it easier to add SG support,
let's split the big loop out to its own function.

Signed-off-by: default avatarFelipe Balbi <balbi@ti.com>
parent 898c6086

drivers/usb/dwc3/gadget.c

+78 −68
Original line number Diff line number Diff line
@@ -539,6 +539,78 @@ static void dwc3_gadget_ep_free_request(struct usb_ep *ep, 
	kfree(req);

}



/**

 * dwc3_prepare_one_trb - setup one TRB from one request

 * @dep: endpoint for which this request is prepared

 * @req: dwc3_request pointer

 */

static int dwc3_prepare_one_trb(struct dwc3_ep *dep,

		struct dwc3_request *req, unsigned last)

{

	struct dwc3_trb_hw	*trb_hw;

	struct dwc3_trb		trb;



	unsigned int		cur_slot;



	trb_hw = &dep->trb_pool[dep->free_slot & DWC3_TRB_MASK];

	cur_slot = dep->free_slot;

	dep->free_slot++;



	/* Skip the LINK-TRB on ISOC */

	if (((cur_slot & DWC3_TRB_MASK) == DWC3_TRB_NUM - 1) &&

			usb_endpoint_xfer_isoc(dep->desc))

		return 0;



	dwc3_gadget_move_request_queued(req);

	memset(&trb, 0, sizeof(trb));



	req->trb = trb_hw;



	if (usb_endpoint_xfer_isoc(dep->desc)) {

		trb.isp_imi = true;

		trb.csp = true;

	} else {

		trb.lst = last;

	}



	if (usb_endpoint_xfer_bulk(dep->desc) && dep->stream_capable)

		trb.sid_sofn = req->request.stream_id;



	switch (usb_endpoint_type(dep->desc)) {

	case USB_ENDPOINT_XFER_CONTROL:

		trb.trbctl = DWC3_TRBCTL_CONTROL_SETUP;

		break;



	case USB_ENDPOINT_XFER_ISOC:

		trb.trbctl = DWC3_TRBCTL_ISOCHRONOUS_FIRST;



		/* IOC every DWC3_TRB_NUM / 4 so we can refill */

		if (!(cur_slot % (DWC3_TRB_NUM / 4)))

			trb.ioc = last;

		break;



	case USB_ENDPOINT_XFER_BULK:

	case USB_ENDPOINT_XFER_INT:

		trb.trbctl = DWC3_TRBCTL_NORMAL;

		break;

	default:

		/*

		 * This is only possible with faulty memory because we

		 * checked it already :)

		 */

		BUG();

	}



	trb.length	= req->request.length;

	trb.bplh	= req->request.dma;

	trb.hwo		= true;



	dwc3_trb_to_hw(&trb, trb_hw);

	req->trb_dma = dwc3_trb_dma_offset(dep, trb_hw);



	return 0;

}



/*

 * dwc3_prepare_trbs - setup TRBs from requests

 * @dep: endpoint for which requests are being prepared
@@ -552,14 +624,14 @@ static struct dwc3_request *dwc3_prepare_trbs(struct dwc3_ep *dep, 
		bool starting)

{

	struct dwc3_request	*req, *n, *ret = NULL;

	struct dwc3_trb_hw	*trb_hw;

	struct dwc3_trb		trb;

	u32			trbs_left;

	unsigned int		last_one = 0;



	BUILD_BUG_ON_NOT_POWER_OF_2(DWC3_TRB_NUM);



	/* the first request must not be queued */

	trbs_left = (dep->busy_slot - dep->free_slot) & DWC3_TRB_MASK;



	/*

	 * if busy & slot are equal than it is either full or empty. If we are

	 * starting to proceed requests then we are empty. Otherwise we ar
@@ -594,25 +666,11 @@ static struct dwc3_request *dwc3_prepare_trbs(struct dwc3_ep *dep, 
		return NULL;



	list_for_each_entry_safe(req, n, &dep->request_list, list) {

		unsigned int last_one = 0;

		unsigned int cur_slot;



		trb_hw = &dep->trb_pool[dep->free_slot & DWC3_TRB_MASK];

		cur_slot = dep->free_slot;

		dep->free_slot++;



		/* Skip the LINK-TRB on ISOC */

		if (((cur_slot & DWC3_TRB_MASK) == DWC3_TRB_NUM - 1) &&

				usb_endpoint_xfer_isoc(dep->desc))

			continue;



		dwc3_gadget_move_request_queued(req);

		memset(&trb, 0, sizeof(trb));

		trbs_left--;



		/* Is our TRB pool empty? */

		if (!trbs_left)

			last_one = 1;



		/* Is this the last request? */

		if (list_empty(&dep->request_list))

			last_one = 1;
@@ -625,56 +683,8 @@ static struct dwc3_request *dwc3_prepare_trbs(struct dwc3_ep *dep, 
		 * While we're debugging the problem, as a workaround to

		 * multiple TRBs handling, use only one TRB at a time.

		 */

		last_one = 1;



		req->trb = trb_hw;

		if (!ret)

		dwc3_prepare_one_trb(dep, req, true);

		ret = req;



		trb.bplh = req->request.dma;



		if (usb_endpoint_xfer_isoc(dep->desc)) {

			trb.isp_imi = true;

			trb.csp = true;

		} else {

			trb.lst = last_one;

		}



		if (usb_endpoint_xfer_bulk(dep->desc) && dep->stream_capable)

			trb.sid_sofn = req->request.stream_id;



		switch (usb_endpoint_type(dep->desc)) {

		case USB_ENDPOINT_XFER_CONTROL:

			trb.trbctl = DWC3_TRBCTL_CONTROL_SETUP;

			break;



		case USB_ENDPOINT_XFER_ISOC:

			trb.trbctl = DWC3_TRBCTL_ISOCHRONOUS_FIRST;



			/* IOC every DWC3_TRB_NUM / 4 so we can refill */

			if (!(cur_slot % (DWC3_TRB_NUM / 4)))

				trb.ioc = last_one;

			break;



		case USB_ENDPOINT_XFER_BULK:

		case USB_ENDPOINT_XFER_INT:

			trb.trbctl = DWC3_TRBCTL_NORMAL;

			break;

		default:

			/*

			 * This is only possible with faulty memory because we

			 * checked it already :)

			 */

			BUG();

		}



		trb.length	= req->request.length;

		trb.hwo = true;



		dwc3_trb_to_hw(&trb, trb_hw);

		req->trb_dma = dwc3_trb_dma_offset(dep, trb_hw);



		if (last_one)

		break;

	}