From 31162af447d7afba6820e42ed9cf968ed74c64cd Mon Sep 17 00:00:00 2001 From: Felipe Balbi Date: Thu, 11 Aug 2016 14:38:37 +0300 Subject: [PATCH] usb: dwc3: gadget: avoid while (1) loop on completion We know that we have to iterate over the list of started requests. Instead of looping forever, we can rely on list_for_each_entry(). Likewise, instead of a do {} while loop over all, maybe available, scatterlist entries, we can detect if $this request uses scatterlist and rely on for_each_sg(). This makes the code easier to follow while making sure that we will *always* break out of the loop. Signed-off-by: Felipe Balbi --- drivers/usb/dwc3/gadget.c | 32 +++++++++++++++++++------------- 1 file changed, 19 insertions(+), 13 deletions(-) diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c index 3cf4c9016b75..c776fb7f524a 100644 --- a/drivers/usb/dwc3/gadget.c +++ b/drivers/usb/dwc3/gadget.c @@ -1926,31 +1926,37 @@ static int __dwc3_cleanup_done_trbs(struct dwc3 *dwc, struct dwc3_ep *dep, static int dwc3_cleanup_done_reqs(struct dwc3 *dwc, struct dwc3_ep *dep, const struct dwc3_event_depevt *event, int status) { - struct dwc3_request *req; + struct dwc3_request *req, *n; struct dwc3_trb *trb; - unsigned int i; int count = 0; int ret; - do { + list_for_each_entry_safe(req, n, &dep->started_list, list) { + int chain; - req = next_request(&dep->started_list); - if (!req) - return 1; - chain = req->request.num_mapped_sgs > 0; - i = 0; - do { + if (chain) { + struct scatterlist *sg = req->request.sg; + struct scatterlist *s; + unsigned int i; + + for_each_sg(sg, s, req->request.num_mapped_sgs, i) { + trb = &dep->trb_pool[dep->trb_dequeue]; + count += trb->size & DWC3_TRB_SIZE_MASK; + dwc3_ep_inc_deq(dep); + + ret = __dwc3_cleanup_done_trbs(dwc, dep, req, trb, + event, status, chain); + } + } else { trb = &dep->trb_pool[dep->trb_dequeue]; count += trb->size & DWC3_TRB_SIZE_MASK; dwc3_ep_inc_deq(dep); ret = __dwc3_cleanup_done_trbs(dwc, dep, req, trb, event, status, chain); - if (ret) - break; - } while (++i < req->request.num_mapped_sgs); + } /* * We assume here we will always receive the entire data block @@ -1964,7 +1970,7 @@ static int dwc3_cleanup_done_reqs(struct dwc3 *dwc, struct dwc3_ep *dep, if (ret) break; - } while (1); + } /* * Our endpoint might get disabled by another thread during