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

From: Ricardo Ribalda Delgado
Date: Thu Mar 11 2021 - 18:00:42 EST


Hi Laurent

On Thu, Mar 11, 2021 at 11:53 PM Laurent Pinchart
<laurent.pinchart@xxxxxxxxxxxxxxxx> wrote:
>
> Hi Ricardo,
>
> Thank you for the patch.

Thank you :)
>
> 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@xxxxxxxxxxxx>
>
> The change looks good to me.
>
> Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
>
> Which of the error codes below do you get with your camera, and for
> which control ?

Bus 001 Device 003: ID 05c8:03a2 Cheng Uei Precision Industry Co., Ltd
(Foxlink) XiaoMi USB 2.0 Webcam

info: checking extended control 'White Balance Temperature' (0x0098091a)
Control error 7
info: checking extended control 'Exposure (Absolute)' (0x009a0902)
Control error 6


>
> > ---
> > 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



--
Ricardo Ribalda