In __dwc3_prepare_one_trb(), IOC bit is set if the total number of available TRB's are zero. The number of available TRBs are calculated using dwc3_calc_trbs_left(), which determines TRBs full or not based on HWO bit set in the TRB. During preparation of TRB __dwc3_prepare_one_trb() is always called with a TRB which doesn't have HWO bit set. __dwc3_prepare_one_trb() depends on dwc3_calc_trbs_left() to calculate the free available TRBs and set IOC bit if not available. Since dwc3_calc_trbs_left() determines TRB available based on HWO bit, there are chances that dwc3_calc_trbs_left() wrongly calculates the present working TRB as free TRB (since HWO bit is not yet set). This patch corrects this issue by setting HWO bit before calling dwc3_calc_trbs_left(). Signed-off-by: Anurag Kumar Vulisha <anurag.kumar.vulisha@xxxxxxxxxx> --- 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 -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
