From ba3a51ac32ebcf8d0a54b37f1af268ad8a31c52f Mon Sep 17 00:00:00 2001 From: Thinh Nguyen Date: Thu, 2 Aug 2018 20:17:16 -0700 Subject: [PATCH] usb: dwc3: gadget: Properly check last unaligned/zero chain TRB Current check for the last extra TRB for zero and unaligned transfers does not account for isoc OUT. The last TRB of the Buffer Descriptor for isoc OUT transfers will be retired with HWO=0. As a result, we won't return early. The req->remaining will be updated to include the BUFSIZ count of the extra TRB, and the actual number of transferred bytes calculation will be wrong. To fix this, check whether it's a short or zero packet and the last TRB chain bit to return early. Fixes: c6267a51639b ("usb: dwc3: gadget: align transfers to wMaxPacketSize") Cc: Signed-off-by: Thinh Nguyen Signed-off-by: Felipe Balbi --- drivers/usb/dwc3/gadget.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c index 679c12e14522..06e22afdf3d1 100644 --- a/drivers/usb/dwc3/gadget.c +++ b/drivers/usb/dwc3/gadget.c @@ -2259,7 +2259,7 @@ static int dwc3_gadget_ep_reclaim_completed_trb(struct dwc3_ep *dep, * with one TRB pending in the ring. We need to manually clear HWO bit * from that TRB. */ - if ((req->zero || req->unaligned) && (trb->ctrl & DWC3_TRB_CTRL_HWO)) { + if ((req->zero || req->unaligned) && !(trb->ctrl & DWC3_TRB_CTRL_CHN)) { trb->ctrl &= ~DWC3_TRB_CTRL_HWO; return 1; }