Availability of TRB's are calculated using dwc3_calc_trbs_left(), which determines available TRB's based on the HWO bit set in a TRB. __dwc3_prepare_one_trb() is called with a TRB which needs to be prepared for transfer. This __dwc3_prepare_one_trb() calls dwc3_calc_trbs_left() to determine total available TRBs and set IOC bit if the total available TRBs are zero. Since the present working TRB(which is passed as an argument to __dwc3_prepare_one_trb() ) doesn't have HWO bit already set, there are chances where dwc3_calc_trbs_left() wrongly calculates this present working TRB as free(since the HWO bit is not yet set). This could be a problem. This patch correct this issue by setting HWO bit before calling dwc3_calc_trbs_left() Signed-off-by: Anurag Kumar Vulisha <anurag.kumar.vulisha@xxxxxxxxxx> --- Changes in v2: 1. Changed the commit message --- drivers/usb/dwc3/gadget.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c index 69bf137..f73d219 100644 --- a/drivers/usb/dwc3/gadget.c +++ b/drivers/usb/dwc3/gadget.c @@ -990,6 +990,8 @@ static void __dwc3_prepare_one_trb(struct dwc3_ep *dep, struct dwc3_trb *trb, trb->ctrl |= DWC3_TRB_CTRL_ISP_IMI; } + trb->ctrl |= DWC3_TRB_CTRL_HWO; + if ((!no_interrupt && !chain) || (dwc3_calc_trbs_left(dep) == 0)) trb->ctrl |= DWC3_TRB_CTRL_IOC; @@ -1000,8 +1002,6 @@ static void __dwc3_prepare_one_trb(struct dwc3_ep *dep, struct dwc3_trb *trb, if (usb_endpoint_xfer_bulk(dep->endpoint.desc) && dep->stream_capable) trb->ctrl |= DWC3_TRB_CTRL_SID_SOFN(stream_id); - trb->ctrl |= DWC3_TRB_CTRL_HWO; - trace_dwc3_prepare_trb(dep, trb); } -- 2.1.1
