Re: [PATCH v4 6/8] media: v4l2-ctrls: Add RGB color effects control

[Hans Verkuil <hverkuil-cisco@xs4all.nl>]

On 14/10/2021 12:25, dillon.minfei@gmail.com wrote:
> From: Dillon Min <dillon.minfei@gmail.com>
> 
> Add V4L2_COLORFX_SET_RGB color effects control, V4L2_CID_COLORFX_RGB
> for RGB color setting.
> 
> Signed-off-by: Dillon Min <dillon.minfei@gmail.com>
> ---
> v4:
> - replace V4L2_COLORFX_SET_ARGB, V4L2_CID_COLORFX_ARGB to
>   V4L2_COLORFX_SET_RGB, V4L2_CID_COLORFX_RGB since Alpha paramter not used
>   in current. thanks Hans.
> 
>  Documentation/userspace-api/media/v4l/control.rst | 9 +++++++++
>  drivers/media/v4l2-core/v4l2-ctrls-defs.c         | 2 ++
>  include/uapi/linux/v4l2-controls.h                | 4 +++-
>  3 files changed, 14 insertions(+), 1 deletion(-)
> 
> diff --git a/Documentation/userspace-api/media/v4l/control.rst b/Documentation/userspace-api/media/v4l/control.rst
> index f8d0b923da20..3eec65174260 100644
> --- a/Documentation/userspace-api/media/v4l/control.rst
> +++ b/Documentation/userspace-api/media/v4l/control.rst
> @@ -242,8 +242,17 @@ Control IDs
>      * - ``V4L2_COLORFX_SET_CBCR``
>        - The Cb and Cr chroma components are replaced by fixed coefficients
>  	determined by ``V4L2_CID_COLORFX_CBCR`` control.
> +    * - ``V4L2_COLORFX_SET_RGB``
> +      - The RGB components are replaced by the fixed RGB components determined
> +        by ``V4L2_CID_COLORFX_RGB`` control.
>  
>  
> +``V4L2_CID_COLORFX_RGB`` ``(integer)``
> +    Determines the Red, Green, and Blue coefficients for
> +    ``V4L2_COLORFX_SET_RGB`` color effect.
> +    Bits [7:0] of the supplied 32 bit value are interpreted as Blue component,
> +    bits [15:8] as Green component, bits [23:16] as Red component, and
> +    bits [31:24] must be zero.
>  
>  ``V4L2_CID_COLORFX_CBCR`` ``(integer)``
>      Determines the Cb and Cr coefficients for ``V4L2_COLORFX_SET_CBCR``
> diff --git a/drivers/media/v4l2-core/v4l2-ctrls-defs.c b/drivers/media/v4l2-core/v4l2-ctrls-defs.c
> index 421300e13a41..f4bd90170105 100644
> --- a/drivers/media/v4l2-core/v4l2-ctrls-defs.c
> +++ b/drivers/media/v4l2-core/v4l2-ctrls-defs.c
> @@ -785,6 +785,7 @@ const char *v4l2_ctrl_get_name(u32 id)
>  	case V4L2_CID_MIN_BUFFERS_FOR_OUTPUT:	return "Min Number of Output Buffers";
>  	case V4L2_CID_ALPHA_COMPONENT:		return "Alpha Component";
>  	case V4L2_CID_COLORFX_CBCR:		return "Color Effects, CbCr";
> +	case V4L2_CID_COLORFX_RGB:		return "Color Effects, RGB";
>  
>  	/*
>  	 * Codec controls
> @@ -1392,6 +1393,7 @@ void v4l2_ctrl_fill(u32 id, const char **name, enum v4l2_ctrl_type *type,
>  		*min = *max = *step = *def = 0;
>  		break;
>  	case V4L2_CID_BG_COLOR:
> +	case V4L2_CID_COLORFX_RGB:
>  		*type = V4L2_CTRL_TYPE_INTEGER;
>  		*step = 1;
>  		*min = 0;

Can you make another small change here? Please change:

	*max = 0xFFFFFF;

to:

	*max = 0xffffff;

to keep in line with the coding standard for hex values.

Also, can you add a separate patch that adds an entry here for V4L2_CID_COLORFX_CBCR
that sets *max to 0xffff? I noticed that that was missing. While adding V4L2_CID_COLORFX_RGB
it's good to fix V4L2_CID_COLORFX_CBCR as well.

Regards,

	Hans

> diff --git a/include/uapi/linux/v4l2-controls.h b/include/uapi/linux/v4l2-controls.h
> index 5532b5f68493..9aa3fd368383 100644
> --- a/include/uapi/linux/v4l2-controls.h
> +++ b/include/uapi/linux/v4l2-controls.h
> @@ -128,6 +128,7 @@ enum v4l2_colorfx {
>  	V4L2_COLORFX_SOLARIZATION		= 13,
>  	V4L2_COLORFX_ANTIQUE			= 14,
>  	V4L2_COLORFX_SET_CBCR			= 15,
> +	V4L2_COLORFX_SET_RGB			= 16,
>  };
>  #define V4L2_CID_AUTOBRIGHTNESS			(V4L2_CID_BASE+32)
>  #define V4L2_CID_BAND_STOP_FILTER		(V4L2_CID_BASE+33)
> @@ -145,9 +146,10 @@ enum v4l2_colorfx {
>  
>  #define V4L2_CID_ALPHA_COMPONENT		(V4L2_CID_BASE+41)
>  #define V4L2_CID_COLORFX_CBCR			(V4L2_CID_BASE+42)
> +#define V4L2_CID_COLORFX_RGB			(V4L2_CID_BASE+43)
>  
>  /* last CID + 1 */
> -#define V4L2_CID_LASTP1                         (V4L2_CID_BASE+43)
> +#define V4L2_CID_LASTP1                         (V4L2_CID_BASE+44)
>  
>  /* USER-class private control IDs */
>  
>