From 55a0237f8f47957163125e20ee9260538c5c341c Mon Sep 17 00:00:00 2001 From: Felipe Balbi Date: Mon, 30 May 2016 13:38:32 +0300 Subject: [PATCH] usb: dwc3: gadget: use allocated/queued reqs for LST bit Let's only set LST bit when we run out of space in our TRB ring. For all other cases, we keep LST bit unset which will prevent constant allocation and deallocation of endpoint transfer resources. Signed-off-by: Felipe Balbi --- drivers/usb/dwc3/gadget.c | 20 ++++++++++++++------ 1 file changed, 14 insertions(+), 6 deletions(-) diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c index a7c2548166b0..eea412720f33 100644 --- a/drivers/usb/dwc3/gadget.c +++ b/drivers/usb/dwc3/gadget.c @@ -897,7 +897,8 @@ static u32 dwc3_calc_trbs_left(struct dwc3_ep *dep) } static void dwc3_prepare_one_trb_sg(struct dwc3_ep *dep, - struct dwc3_request *req, unsigned int trbs_left) + struct dwc3_request *req, unsigned int trbs_left, + unsigned int more_coming) { struct usb_request *request = &req->request; struct scatterlist *sg = request->sg; @@ -914,7 +915,8 @@ static void dwc3_prepare_one_trb_sg(struct dwc3_ep *dep, dma = sg_dma_address(s); if (sg_is_last(s)) { - if (list_is_last(&req->list, &dep->pending_list)) + if (usb_endpoint_xfer_int(dep->endpoint.desc) || + !more_coming) last = true; chain = false; @@ -935,7 +937,8 @@ static void dwc3_prepare_one_trb_sg(struct dwc3_ep *dep, } static void dwc3_prepare_one_trb_linear(struct dwc3_ep *dep, - struct dwc3_request *req, unsigned int trbs_left) + struct dwc3_request *req, unsigned int trbs_left, + unsigned int more_coming) { unsigned int last = false; unsigned int length; @@ -948,7 +951,7 @@ static void dwc3_prepare_one_trb_linear(struct dwc3_ep *dep, last = true; /* Is this the last request? */ - if (list_is_last(&req->list, &dep->pending_list)) + if (usb_endpoint_xfer_int(dep->endpoint.desc) || !more_coming) last = true; dwc3_prepare_one_trb(dep, req, dma, length, @@ -966,6 +969,7 @@ static void dwc3_prepare_one_trb_linear(struct dwc3_ep *dep, static void dwc3_prepare_trbs(struct dwc3_ep *dep) { struct dwc3_request *req, *n; + unsigned int more_coming; u32 trbs_left; BUILD_BUG_ON_NOT_POWER_OF_2(DWC3_TRB_NUM); @@ -974,11 +978,15 @@ static void dwc3_prepare_trbs(struct dwc3_ep *dep) if (!trbs_left) return; + more_coming = dep->allocated_requests - dep->queued_requests; + list_for_each_entry_safe(req, n, &dep->pending_list, list) { if (req->request.num_mapped_sgs > 0) - dwc3_prepare_one_trb_sg(dep, req, trbs_left--); + dwc3_prepare_one_trb_sg(dep, req, trbs_left--, + more_coming); else - dwc3_prepare_one_trb_linear(dep, req, trbs_left--); + dwc3_prepare_one_trb_linear(dep, req, trbs_left--, + more_coming); if (!trbs_left) return; -- 2.20.1