Re: [PATCH] usb: dwc2: gadget: fix ISOC frame overflow handling

From: Minas Harutyunyan
Date: Mon Nov 05 2018 - 03:28:14 EST


Hi John,

On 10/23/2018 5:43 PM, John Keeping wrote:
> By clearing the overrun flag as soon as the target frame is next
> incremented, we can end up incrementing the target frame more than
> expected in dwc2_gadget_handle_ep_disabled() when the endpoint's
> interval is greater than 1. This happens if the target frame has just
> wrapped at the point when the endpoint is disabled and the frame number
> has not yet done so.
>
> Instead, wait until the frame number also wraps and then clear the
> overrun flag.
>
> Signed-off-by: John Keeping <john@xxxxxxxxxxxx>
> ---
> drivers/usb/dwc2/gadget.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c
> index 2d6d2c8244de..8da2c052dfa1 100644
> --- a/drivers/usb/dwc2/gadget.c
> +++ b/drivers/usb/dwc2/gadget.c
> @@ -117,7 +117,7 @@ static inline void dwc2_gadget_incr_frame_num(struct dwc2_hsotg_ep *hs_ep)
> if (hs_ep->target_frame > DSTS_SOFFN_LIMIT) {
> hs_ep->frame_overrun = true;
> hs_ep->target_frame &= DSTS_SOFFN_LIMIT;
> - } else {
> + } else if (hs_ep->parent->frame_number < hs_ep->target_frame) {
> hs_ep->frame_overrun = false;
> }
> }
>
Did you tested mentioned by you scenario? If you see issue can you
provide debug log and point the issue line in the log.

Thanks,
Minas