From 55168470835688e5da5828cdcf1b1498d7baadb1 Mon Sep 17 00:00:00 2001 From: Felipe Balbi Date: Mon, 11 Sep 2017 10:45:12 +0300 Subject: [PATCH] usb: dwc3: ep0: fix DMA starvation by assigning req->trb on ep0 If we don't assign a TRB to ep0 requests, we won't be able to unmap the request later on resulting in starvation of DMA resources. Fixes: 4a71fcb8ac5f ("usb: dwc3: gadget: only unmap requests from DMA if mapped") Reported-by: Thinh Nguyen Tested-by: Thinh Nguyen Signed-off-by: Felipe Balbi --- drivers/usb/dwc3/ep0.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/usb/dwc3/ep0.c b/drivers/usb/dwc3/ep0.c index 827e376..75e6cb0 100644 --- a/drivers/usb/dwc3/ep0.c +++ b/drivers/usb/dwc3/ep0.c @@ -990,6 +990,8 @@ static void __dwc3_ep0_do_control_data(struct dwc3 *dwc, DWC3_TRBCTL_CONTROL_DATA, true); + req->trb = &dwc->ep0_trb[dep->trb_enqueue - 1]; + /* Now prepare one extra TRB to align transfer size */ dwc3_ep0_prepare_one_trb(dep, dwc->bounce_addr, maxpacket - rem, @@ -1015,6 +1017,8 @@ static void __dwc3_ep0_do_control_data(struct dwc3 *dwc, DWC3_TRBCTL_CONTROL_DATA, true); + req->trb = &dwc->ep0_trb[dep->trb_enqueue - 1]; + /* Now prepare one extra TRB to align transfer size */ dwc3_ep0_prepare_one_trb(dep, dwc->bounce_addr, 0, DWC3_TRBCTL_CONTROL_DATA, @@ -1029,6 +1033,9 @@ static void __dwc3_ep0_do_control_data(struct dwc3 *dwc, dwc3_ep0_prepare_one_trb(dep, req->request.dma, req->request.length, DWC3_TRBCTL_CONTROL_DATA, false); + + req->trb = &dwc->ep0_trb[dep->trb_enqueue]; + ret = dwc3_ep0_start_trans(dep); } -- 2.7.4