Re: [PATCH v15 07/19] media: uvcvideo: refactor uvc_ioctl_g_ext_ctrls

[Hans de Goede <hdegoede@redhat.com>]

Hi,

On 14-Nov-24 8:10 PM, Ricardo Ribalda wrote:
> We want to support fetching the min and max values with g_ext_ctrls,
> this patch is a preparation for that.
> 
> Instead of abusing uvc_query_v4l2_ctrl(), add an extra parameter to
> uvc_ctrl_get, so it can support fetching the default value.
> 
> Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>

Thanks, patch looks good to me:

Reviewed-by: Hans de Goede <hdegoede@redhat.com>

Regards,

Hans



> ---
>  drivers/media/usb/uvc/uvc_ctrl.c | 21 ++++++++++++++++++---
>  drivers/media/usb/uvc/uvc_v4l2.c | 28 +++++++++++-----------------
>  drivers/media/usb/uvc/uvcvideo.h |  3 ++-
>  3 files changed, 31 insertions(+), 21 deletions(-)
> 
> diff --git a/drivers/media/usb/uvc/uvc_ctrl.c b/drivers/media/usb/uvc/uvc_ctrl.c
> index c975e0ab479b..d6afa131a5e1 100644
> --- a/drivers/media/usb/uvc/uvc_ctrl.c
> +++ b/drivers/media/usb/uvc/uvc_ctrl.c
> @@ -1902,8 +1902,8 @@ int __uvc_ctrl_commit(struct uvc_fh *handle, int rollback,
>  	return ret;
>  }
>  
> -int uvc_ctrl_get(struct uvc_video_chain *chain,
> -	struct v4l2_ext_control *xctrl)
> +int uvc_ctrl_get(struct uvc_video_chain *chain, u32 which,
> +		 struct v4l2_ext_control *xctrl)
>  {
>  	struct uvc_control *ctrl;
>  	struct uvc_control_mapping *mapping;
> @@ -1915,7 +1915,22 @@ int uvc_ctrl_get(struct uvc_video_chain *chain,
>  	if (ctrl == NULL)
>  		return -EINVAL;
>  
> -	return __uvc_ctrl_get(chain, ctrl, mapping, &xctrl->value);
> +	switch (which) {
> +	case V4L2_CTRL_WHICH_CUR_VAL:
> +		return __uvc_ctrl_get(chain, ctrl, mapping, &xctrl->value);
> +	case V4L2_CTRL_WHICH_DEF_VAL:
> +		if (!ctrl->cached) {
> +			int ret = uvc_ctrl_populate_cache(chain, ctrl);
> +
> +			if (ret < 0)
> +				return ret;
> +		}
> +		xctrl->value = mapping->get(mapping, UVC_GET_DEF,
> +					    uvc_ctrl_data(ctrl, UVC_CTRL_DATA_DEF));
> +		return 0;
> +	}
> +
> +	return -EINVAL;
>  }
>  
>  int uvc_ctrl_set(struct uvc_fh *handle,
> diff --git a/drivers/media/usb/uvc/uvc_v4l2.c b/drivers/media/usb/uvc/uvc_v4l2.c
> index 97c5407f6603..02fd5cbc3474 100644
> --- a/drivers/media/usb/uvc/uvc_v4l2.c
> +++ b/drivers/media/usb/uvc/uvc_v4l2.c
> @@ -1078,34 +1078,28 @@ static int uvc_ioctl_g_ext_ctrls(struct file *file, void *fh,
>  	struct uvc_video_chain *chain = handle->chain;
>  	struct v4l2_ext_control *ctrl = ctrls->controls;
>  	unsigned int i;
> +	u32 which;
>  	int ret;
>  
> +	switch (ctrls->which) {
> +	case V4L2_CTRL_WHICH_DEF_VAL:
> +	case V4L2_CTRL_WHICH_CUR_VAL:
> +		which = ctrls->which;
> +		break;
> +	default:
> +		which = V4L2_CTRL_WHICH_CUR_VAL;
> +	}
> +
>  	ret = uvc_ctrl_check_access(chain, ctrls, VIDIOC_G_EXT_CTRLS);
>  	if (ret < 0)
>  		return ret;
>  
> -	if (ctrls->which == V4L2_CTRL_WHICH_DEF_VAL) {
> -		for (i = 0; i < ctrls->count; ++ctrl, ++i) {
> -			struct v4l2_queryctrl qc = { .id = ctrl->id };
> -
> -			ret = uvc_query_v4l2_ctrl(chain, &qc);
> -			if (ret < 0) {
> -				ctrls->error_idx = i;
> -				return ret;
> -			}
> -
> -			ctrl->value = qc.default_value;
> -		}
> -
> -		return 0;
> -	}
> -
>  	ret = uvc_ctrl_begin(chain);
>  	if (ret < 0)
>  		return ret;
>  
>  	for (i = 0; i < ctrls->count; ++ctrl, ++i) {
> -		ret = uvc_ctrl_get(chain, ctrl);
> +		ret = uvc_ctrl_get(chain, which, ctrl);
>  		if (ret < 0) {
>  			uvc_ctrl_rollback(handle);
>  			ctrls->error_idx = i;
> diff --git a/drivers/media/usb/uvc/uvcvideo.h b/drivers/media/usb/uvc/uvcvideo.h
> index 07f9921d83f2..6ebaabd11443 100644
> --- a/drivers/media/usb/uvc/uvcvideo.h
> +++ b/drivers/media/usb/uvc/uvcvideo.h
> @@ -788,7 +788,8 @@ static inline int uvc_ctrl_rollback(struct uvc_fh *handle)
>  	return __uvc_ctrl_commit(handle, 1, NULL);
>  }
>  
> -int uvc_ctrl_get(struct uvc_video_chain *chain, struct v4l2_ext_control *xctrl);
> +int uvc_ctrl_get(struct uvc_video_chain *chain, u32 which,
> +		 struct v4l2_ext_control *xctrl);
>  int uvc_ctrl_set(struct uvc_fh *handle, struct v4l2_ext_control *xctrl);
>  int uvc_ctrl_is_accessible(struct uvc_video_chain *chain, u32 v4l2_id,
>  			   const struct v4l2_ext_controls *ctrls,
>