On Wed, Aug 14, 2024 at 07:25:37PM +0800, Xu Yang wrote:
> Since commit "6acba0345b68 usb:gadget:uvc Do not use worker thread to pump
> isoc usb requests", pump work could only be queued in uvc_video_complete()
> and uvc_v4l2_qbuf(). If VIDIOC_QBUF is executed before VIDIOC_STREAMON,
> we can only depend on uvc_video_complete() to queue pump work. However,
> this requires some free requests in req_ready list. If req_ready list is
> empty all the time, pump work will never be queued and video datas will
> never be pumped to usb controller. Actually, this situation could happen
> when run uvc-gadget with static image:
>
> $ ./uvc-gadget -i 1080p.jpg uvc.0
>
> When capture image from this device, the user app will always block there.
>
> The issue is uvc driver has queued video buffer before streamon, but the
> req_ready list is empty all the time after streamon. This will queue pump
> work in uvcg_video_enable() to fill some request to req_ready list so the
> uvc device could work properly.
>
> Fixes: 6acba0345b68 ("usb:gadget:uvc Do not use worker thread to pump isoc usb requests")
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Xu Yang <xu.yang_2@xxxxxxx>
> ---
> drivers/usb/gadget/function/uvc_video.c | 1 +
> 1 file changed, 1 insertion(+)
Why is this a RESEND? What happened to the first one to require this?
thanks,
greg k-h
