From: Fei Yang fei.yang@intel.com

If scatter-gather operation is allowed, a large USB request is split into multiple TRBs. These TRBs are chained up by setting DWC3_TRB_CTRL_CHN bit except the last one which has DWC3_TRB_CTRL_IOC bit set instead. Since only the last TRB has IOC set for the whole USB request, the dwc3_gadget_ep_reclaim_completed_trb() gets called only once for the request and all TRBs are supposed to be reclaimed. However that is not what happens with the current code.

This patch addresses the issue by checking req->num_pending_sgs. In case the pending sgs is not zero, update trb_dequeue and req->num_trbs accordingly.

Signed-off-by: Fei Yang fei.yang@intel.com Cc: stable stable@vger.kernel.org --- drivers/usb/dwc3/gadget.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c index 173f532..4d5b4eb 100644 --- a/drivers/usb/dwc3/gadget.c +++ b/drivers/usb/dwc3/gadget.c @@ -2394,8 +2394,14 @@ static int dwc3_gadget_ep_reclaim_completed_trb(struct dwc3_ep *dep, if (event->status & DEPEVT_STATUS_SHORT && !chain) return 1;

- if (event->status & DEPEVT_STATUS_IOC) + if (event->status & DEPEVT_STATUS_IOC) { + for (count = 0; count < req->num_pending_sgs; count++) { + dwc3_ep_inc_deq(dep); + req->num_trbs--; + } + req->num_pending_sgs = 0; return 1; + }

return 0; } @@ -2404,7 +2410,7 @@ static int dwc3_gadget_ep_reclaim_trb_sg(struct dwc3_ep *dep, struct dwc3_request *req, const struct dwc3_event_depevt *event, int status) { - struct dwc3_trb *trb = &dep->trb_pool[dep->trb_dequeue]; + struct dwc3_trb *trb; struct scatterlist *sg = req->sg; struct scatterlist *s; unsigned int pending = req->num_pending_sgs;