From 7282c4ef0b66bb3b715ba8875e4e30392e77c7c1 Mon Sep 17 00:00:00 2001 From: Felipe Balbi Date: Tue, 25 Oct 2016 13:50:46 +0300 Subject: [PATCH] usb: dwc3: gadget: stop touching HWO TRBs Say we have three requests prepared to the HW (reqA, reqB, and reqC). All of them are composed of SG-lists with several entries and they all requests interrupt only on last TRBs of the SG-list. When we get interrupt for reqA, it could be that reqB is already half-way transferred and some of its TRBs will have HWO already cleared. It's okay to free up TRBs without HWO bit set, but we need to guarantee we don't giveback a request that's half-way transferred as that will confuse gadget drivers. Signed-off-by: Felipe Balbi --- drivers/usb/dwc3/gadget.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c index 317bb9aed4a4..4643c25702ae 100644 --- a/drivers/usb/dwc3/gadget.c +++ b/drivers/usb/dwc3/gadget.c @@ -2104,6 +2104,9 @@ static int dwc3_cleanup_done_reqs(struct dwc3 *dwc, struct dwc3_ep *dep, for_each_sg(sg, s, pending, i) { trb = &dep->trb_pool[dep->trb_dequeue]; + if (trb->ctrl & DWC3_TRB_CTRL_HWO) + break; + req->sg = sg_next(s); req->num_pending_sgs--;