Re: [PATCH v2 3/6] media: uvcvideo: Return -EIO for control errors

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

Hi Ricardo,

Thank you for the patch.

On Thu, Mar 11, 2021 at 11:19:43PM +0100, Ricardo Ribalda wrote:
> The device is doing something unspected with the control. Either because
> the protocol is not properly implemented or there has been a HW error.
> 
> Fixes v4l2-compliance:
> 
> Control ioctls (Input 0):
>                 fail: v4l2-test-controls.cpp(448): s_ctrl returned an error (22)
>         test VIDIOC_G/S_CTRL: FAIL
>                 fail: v4l2-test-controls.cpp(698): s_ext_ctrls returned an error (22)
>         test VIDIOC_G/S/TRY_EXT_CTRLS: FAIL
> 
> Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>

The change looks good to me.

Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

Which of the error codes below do you get with your camera, and for
which control ?

> ---
>  drivers/media/usb/uvc/uvc_video.c | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/drivers/media/usb/uvc/uvc_video.c b/drivers/media/usb/uvc/uvc_video.c
> index f2f565281e63..25fd8aa23529 100644
> --- a/drivers/media/usb/uvc/uvc_video.c
> +++ b/drivers/media/usb/uvc/uvc_video.c
> @@ -112,6 +112,11 @@ int uvc_query_ctrl(struct uvc_device *dev, u8 query, u8 unit,
>  	case 5: /* Invalid unit */
>  	case 6: /* Invalid control */
>  	case 7: /* Invalid Request */
> +		/*
> +		 * The firmware has not properly implemented
> +		 * the control or there has been a HW error.
> +		 */
> +		return -EIO;
>  	case 8: /* Invalid value within range */
>  		return -EINVAL;
>  	default: /* reserved or unknown */

-- 
Regards,

Laurent Pinchart