Re: [PATCH v2 1/2] media: i2c: vd55g1: Mark the AE lock and bias controls inactive in manual mode

[Sakari Ailus <sakari.ailus@linux.intel.com>]

Hi Fernando, Hans,

On Sun, Nov 01, 2026 at 07:50:04PM +0000, Fernando Rimoli wrote:
> In manual exposure mode the auto exposure lock and bias controls have
> no effect, and the driver marks them grabbed. The grabbed flag means a
> control is temporarily locked, for instance while streaming, so
> v4l2-compliance fails on it while the sensor is idle:
> 
>   fail: v4l2-test-controls.cpp(134): GRABBED flag set
>   test VIDIOC_QUERY_EXT_CTRL/QUERYMENU: FAIL
>   test VIDIOC_QUERYCTRL: FAIL

Hans: v4l-utils commit 0a4d4accea726 adds a check for this but the commit
message doesn't explain why. I don't think grabbing a control is a bug as
such; it's normal that if exposure is set to auto, you can't access the
manual exposure controls.

> 
> A control that does not apply to the current configuration is what the
> inactive flag is for. Use v4l2_ctrl_activate() instead.
> 
> Setting the controls in manual mode now stores the value rather than
> returning -EBUSY. That has no effect on the sensor:
> vd55g1_lock_exposure() writes only in auto mode, and the bias sets the
> auto exposure target, which the sensor uses only once auto exposure
> resumes.
> 
> Signed-off-by: Fernando Rimoli <fernandorimoli11@gmail.com>
> ---
>  drivers/media/i2c/vd55g1.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/media/i2c/vd55g1.c b/drivers/media/i2c/vd55g1.c
> index e3939bb..69ffb3a 100644
> --- a/drivers/media/i2c/vd55g1.c
> +++ b/drivers/media/i2c/vd55g1.c
> @@ -1503,8 +1503,8 @@ static int vd55g1_s_ctrl(struct v4l2_ctrl *ctrl)
>  		break;
>  	case V4L2_CID_EXPOSURE_AUTO:
>  		is_auto = (ctrl->val == V4L2_EXPOSURE_AUTO);
> -		__v4l2_ctrl_grab(sensor->ae_lock_ctrl, !is_auto);
> -		__v4l2_ctrl_grab(sensor->ae_bias_ctrl, !is_auto);
> +		v4l2_ctrl_activate(sensor->ae_lock_ctrl, is_auto);
> +		v4l2_ctrl_activate(sensor->ae_bias_ctrl, is_auto);
>  		break;
>  	case V4L2_CID_HDR_SENSOR_MODE:
>  		/* Discriminate if the userspace changed the control value */

-- 
Regards,

Sakari Ailus