From 346a15cdf65263d8a8dfdbc5d2702471a2dcef6c Mon Sep 17 00:00:00 2001 From: Thinh Nguyen Date: Wed, 30 Sep 2020 17:44:32 -0700 Subject: usb: dwc3: gadget: Keep TRBs in request order If we couldn't finish preparing all the TRBs of a request, don't prepare the next request. Otherwise, the TRBs order will be mixed up and the controller will process the wrong TRB. This is a corner case where there's not enough TRBs for a request that needs the extra TRB but there's still 1 available TRB in the pool. Signed-off-by: Thinh Nguyen Signed-off-by: Felipe Balbi --- drivers/usb/dwc3/gadget.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) (limited to 'drivers/usb') diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c index 327cd556e8db..ff924656f690 100644 --- a/drivers/usb/dwc3/gadget.c +++ b/drivers/usb/dwc3/gadget.c @@ -1274,7 +1274,7 @@ static int dwc3_prepare_trbs(struct dwc3_ep *dep) list_for_each_entry(req, &dep->started_list, list) { if (req->num_pending_sgs > 0) { ret = dwc3_prepare_trbs_sg(dep, req); - if (!ret) + if (!ret || req->num_pending_sgs) return ret; } @@ -1303,10 +1303,13 @@ static int dwc3_prepare_trbs(struct dwc3_ep *dep) req->num_queued_sgs = 0; req->num_pending_sgs = req->request.num_mapped_sgs; - if (req->num_pending_sgs > 0) + if (req->num_pending_sgs > 0) { ret = dwc3_prepare_trbs_sg(dep, req); - else + if (req->num_pending_sgs) + return ret; + } else { ret = dwc3_prepare_trbs_linear(dep, req); + } if (!ret || !dwc3_calc_trbs_left(dep)) return ret; -- cgit v1.2.3