Re: [PATCH v2 1/7] media: uvcvideo: Allow custom control mapping

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

Hi Ricardo,

Thank you for the patch.

On Mon, Jun 10, 2024 at 11:09:52PM +0000, Ricardo Ribalda wrote:
> Some advanced controls might not be completely implemented by vendors.
> 
> If the controls are a enumeration, UVC does not gives a way to probe
> what is implemented and what is not.
> 
> Let's create a new callback function where heuristics can be implemented
> to detect what is implemented and what not.
> 
> Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
> Signed-off-by: Ricardo Ribalda <ribalda@chromium.org>

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

> ---
>  drivers/media/usb/uvc/uvc_ctrl.c | 10 +++++++++-
>  drivers/media/usb/uvc/uvcvideo.h |  5 +++++
>  2 files changed, 14 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/media/usb/uvc/uvc_ctrl.c b/drivers/media/usb/uvc/uvc_ctrl.c
> index e59a463c2761..44ec185a8c8b 100644
> --- a/drivers/media/usb/uvc/uvc_ctrl.c
> +++ b/drivers/media/usb/uvc/uvc_ctrl.c
> @@ -2360,7 +2360,7 @@ static int uvc_ctrl_add_info(struct uvc_device *dev, struct uvc_control *ctrl,
>  /*
>   * Add a control mapping to a given control.
>   */
> -static int __uvc_ctrl_add_mapping(struct uvc_video_chain *chain,
> +static int __uvc_ctrl_add_mapping_to_list(struct uvc_video_chain *chain,
>  	struct uvc_control *ctrl, const struct uvc_control_mapping *mapping)
>  {
>  	struct uvc_control_mapping *map;
> @@ -2434,6 +2434,14 @@ static int __uvc_ctrl_add_mapping(struct uvc_video_chain *chain,
>  	return -ENOMEM;
>  }
>  
> +static int __uvc_ctrl_add_mapping(struct uvc_video_chain *chain,
> +	struct uvc_control *ctrl, const struct uvc_control_mapping *mapping)
> +{
> +	if (mapping && mapping->add_mapping)
> +		return mapping->add_mapping(chain, ctrl, mapping);
> +	return __uvc_ctrl_add_mapping_to_list(chain, ctrl, mapping);
> +}
> +
>  int uvc_ctrl_add_mapping(struct uvc_video_chain *chain,
>  	const struct uvc_control_mapping *mapping)
>  {
> diff --git a/drivers/media/usb/uvc/uvcvideo.h b/drivers/media/usb/uvc/uvcvideo.h
> index 6fb0a78b1b00..fa0396dd5b35 100644
> --- a/drivers/media/usb/uvc/uvcvideo.h
> +++ b/drivers/media/usb/uvc/uvcvideo.h
> @@ -84,7 +84,9 @@
>  
>  struct gpio_desc;
>  struct sg_table;
> +struct uvc_control;
>  struct uvc_device;
> +struct uvc_video_chain;
>  
>  /*
>   * TODO: Put the most frequently accessed fields at the beginning of
> @@ -123,6 +125,9 @@ struct uvc_control_mapping {
>  	s32 master_manual;
>  	u32 slave_ids[2];
>  
> +	int (*add_mapping)(struct uvc_video_chain *chain,
> +			   struct uvc_control *ctrl,
> +			   const struct uvc_control_mapping *mapping);
>  	s32 (*get)(struct uvc_control_mapping *mapping, u8 query,
>  		   const u8 *data);
>  	void (*set)(struct uvc_control_mapping *mapping, s32 value,

-- 
Regards,

Laurent Pinchart