Merge "dwc3: gadget: Check available trbs before processing req" (19f7e64d) · Commits · e / devices / android_kernel_sony_msm8994

drivers/usb/dwc3/gadget.c

+59 −6

Original line number	Diff line number	Diff line
		@@ -964,6 +964,11 @@ static void dwc3_prepare_trbs(struct dwc3_ep *dep, bool starting)
		u32 trbs_left;
		u32 max;
		unsigned int last_one = 0;
		int maxpkt_size;
		bool isoc;

		maxpkt_size = usb_endpoint_maxp(dep->endpoint.desc);
		isoc = usb_endpoint_xfer_isoc(dep->endpoint.desc);

		BUILD_BUG_ON_NOT_POWER_OF_2(DWC3_TRB_NUM);

		@@ -1006,17 +1011,31 @@ static void dwc3_prepare_trbs(struct dwc3_ep *dep, bool starting)
		}
		}

		/* The last TRB is a link TRB, not used for xfer */
		if ((trbs_left <= 1) && usb_endpoint_xfer_isoc(dep->endpoint.desc))
		return;

		list_for_each_entry_safe(req, n, &dep->request_list, list) {
		unsigned length;
		dma_addr_t dma;
		bool last_req = list_is_last(&req->list,
		&dep->request_list);
		int num_trbs_required = 0;

		last_one = false;

		/* The last TRB is a link TRB, not used for xfer */
		if (isoc)
		num_trbs_required++;

		if (req->request.num_mapped_sgs)
		num_trbs_required += req->request.num_mapped_sgs;
		else
		num_trbs_required++;

		if (req->request.zero && req->request.length &&
		(req->request.length % maxpkt_size == 0))
		num_trbs_required++;

		if (trbs_left < num_trbs_required)
		break;

		if (req->request.num_mapped_sgs > 0) {
		struct usb_request *request = &req->request;
		struct scatterlist *sg = request->sg;
		@@ -1031,11 +1050,45 @@ static void dwc3_prepare_trbs(struct dwc3_ep *dep, bool starting)

		if (i == (request->num_mapped_sgs - 1) \|\|
		sg_is_last(s)) {
		if (last_req)
		last_one = true;
		unsigned temp = 0;
		unsigned len;
		struct dwc3_request *nreq = n;
		struct usb_request *ureq;
		bool mpkt = false;

		chain = false;
		if (last_req) {
		last_one = true;
		goto start_trb_queuing;
		}

		/*
		* check if trbs sufficient for next
		* request to set the last bit
		*/
		ureq = &nreq->request;
		len = ureq->length;

		if (len % maxpkt_size == 0)
		mpkt = true;

		if (ureq->zero && len && mpkt)
		temp++;

		if (ureq->num_mapped_sgs)
		temp +=
		ureq->num_mapped_sgs;
		else
		temp++;

		if (isoc)
		temp++;

		if (trbs_left <= temp)
		last_one = true;
		}

		start_trb_queuing:
		trbs_left--;
		if (!trbs_left)
		last_one = true;