Message-ID: <36a613ab96fc0145025788a333c30f92bb9c7519.camel@ndufresne.ca>
Subject: Re: [PATCH v2 05/10] media: Add BGR24_12 video format
From:   Nicolas Dufresne <nicolas@ndufresne.ca>
To:     Ming Qian <ming.qian@nxp.com>, mchehab@kernel.org,
        mirela.rabulea@oss.nxp.com, hverkuil-cisco@xs4all.nl
Cc:     shawnguo@kernel.org, s.hauer@pengutronix.de, kernel@pengutronix.de,
        festevam@gmail.com, xiahong.bao@nxp.com, linux-imx@nxp.com,
        linux-media@vger.kernel.org, linux-kernel@vger.kernel.org,
        devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org
Date:   Fri, 10 Feb 2023 11:30:08 -0500
In-Reply-To: <8c74b48e728ecb075a4a65b9771610c9cbe27294.1675230665.git.ming.qian@nxp.com>
References: <cover.1675230665.git.ming.qian@nxp.com>
         <8c74b48e728ecb075a4a65b9771610c9cbe27294.1675230665.git.ming.qian@nxp.com>
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Le mercredi 01 f=C3=A9vrier 2023 =C3=A0 14:02 +0800, Ming Qian a =C3=A9crit=
=C2=A0:
> BGR24_12 is a reversed RGB format with 12 bits per component like BGR24,
> expanded to 16bits.
> Data in the 12 high bits, zeros in the 4 low bits,
> arranged in little endian order.

I would like to suggest BGR48_12

Nicolas

>=20
> Signed-off-by: Ming Qian <ming.qian@nxp.com>
> ---
>  .../userspace-api/media/v4l/pixfmt-rgb.rst    | 35 +++++++++++++++++++
>  drivers/media/v4l2-core/v4l2-common.c         |  1 +
>  drivers/media/v4l2-core/v4l2-ioctl.c          |  1 +
>  include/uapi/linux/videodev2.h                |  3 ++
>  4 files changed, 40 insertions(+)
>=20
> diff --git a/Documentation/userspace-api/media/v4l/pixfmt-rgb.rst b/Docum=
entation/userspace-api/media/v4l/pixfmt-rgb.rst
> index 30f51cd33f99..da29ba69c2d9 100644
> --- a/Documentation/userspace-api/media/v4l/pixfmt-rgb.rst
> +++ b/Documentation/userspace-api/media/v4l/pixfmt-rgb.rst
> @@ -763,6 +763,41 @@ nomenclature that instead use the order of component=
s as seen in a 24- or
>      \normalsize
> =20
> =20
> +More Than 8 Bits Per Component
> +=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D
> +
> +These formats store an RGB triplet in six or eighth bytes, with more tha=
n 8 bits per component.
> +expand the bits per component to 16 bits, data in the high bits, zeros i=
n the low bits,
> +arranged in little endian order.
> +
> +.. raw:: latex
> +
> +    \small
> +
> +.. flat-table:: RGB Formats With More Than 8 Bits Per Component
> +    :header-rows:  1
> +    :stub-columns: 0
> +
> +    * - Identifier
> +      - Code
> +      - Byte 1-0
> +      - Byte 3-2
> +      - Byte 5-4
> +      - Byte 7-6
> +    * .. _V4L2-PIX-FMT-BGR24-12:
> +
> +      - ``V4L2_PIX_FMT_BGR24_12``
> +      - 'B312'
> +
> +      - B\ :sub:`15-4`
> +      - G\ :sub:`15-4`
> +      - R\ :sub:`15-4`
> +      -
> +
> +.. raw:: latex
> +
> +    \normalsize
> +
>  Deprecated RGB Formats
>  =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
> =20
> diff --git a/drivers/media/v4l2-core/v4l2-common.c b/drivers/media/v4l2-c=
ore/v4l2-common.c
> index b3ad02f8cf11..024190f82cf1 100644
> --- a/drivers/media/v4l2-core/v4l2-common.c
> +++ b/drivers/media/v4l2-core/v4l2-common.c
> @@ -252,6 +252,7 @@ const struct v4l2_format_info *v4l2_format_info(u32 f=
ormat)
>  		{ .format =3D V4L2_PIX_FMT_RGB565,  .pixel_enc =3D V4L2_PIXEL_ENC_RGB,=
 .mem_planes =3D 1, .comp_planes =3D 1, .bpp =3D { 2, 0, 0, 0 }, .hdiv =3D =
1, .vdiv =3D 1 },
>  		{ .format =3D V4L2_PIX_FMT_RGB555,  .pixel_enc =3D V4L2_PIXEL_ENC_RGB,=
 .mem_planes =3D 1, .comp_planes =3D 1, .bpp =3D { 2, 0, 0, 0 }, .hdiv =3D =
1, .vdiv =3D 1 },
>  		{ .format =3D V4L2_PIX_FMT_BGR666,  .pixel_enc =3D V4L2_PIXEL_ENC_RGB,=
 .mem_planes =3D 1, .comp_planes =3D 1, .bpp =3D { 4, 0, 0, 0 }, .hdiv =3D =
1, .vdiv =3D 1 },
> +		{ .format =3D V4L2_PIX_FMT_BGR24_12, .pixel_enc =3D V4L2_PIXEL_ENC_RGB=
, .mem_planes =3D 1, .comp_planes =3D 1, .bpp =3D { 6, 0, 0, 0 }, .hdiv =3D=
 1, .vdiv =3D 1 },
> =20
>  		/* YUV packed formats */
>  		{ .format =3D V4L2_PIX_FMT_YUYV,    .pixel_enc =3D V4L2_PIXEL_ENC_YUV,=
 .mem_planes =3D 1, .comp_planes =3D 1, .bpp =3D { 2, 0, 0, 0 }, .hdiv =3D =
2, .vdiv =3D 1 },
> diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-co=
re/v4l2-ioctl.c
> index 711d1b0a8184..329515786abb 100644
> --- a/drivers/media/v4l2-core/v4l2-ioctl.c
> +++ b/drivers/media/v4l2-core/v4l2-ioctl.c
> @@ -1298,6 +1298,7 @@ static void v4l_fill_fmtdesc(struct v4l2_fmtdesc *f=
mt)
>  	case V4L2_PIX_FMT_BGRX32:	descr =3D "32-bit XBGR 8-8-8-8"; break;
>  	case V4L2_PIX_FMT_RGBA32:	descr =3D "32-bit RGBA 8-8-8-8"; break;
>  	case V4L2_PIX_FMT_RGBX32:	descr =3D "32-bit RGBX 8-8-8-8"; break;
> +	case V4L2_PIX_FMT_BGR24_12:	descr =3D "12-bit Depth BGR"; break;
>  	case V4L2_PIX_FMT_GREY:		descr =3D "8-bit Greyscale"; break;
>  	case V4L2_PIX_FMT_Y4:		descr =3D "4-bit Greyscale"; break;
>  	case V4L2_PIX_FMT_Y6:		descr =3D "6-bit Greyscale"; break;
> diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev=
2.h
> index 3eb188581b83..ab52a605e6c0 100644
> --- a/include/uapi/linux/videodev2.h
> +++ b/include/uapi/linux/videodev2.h
> @@ -577,6 +577,9 @@ struct v4l2_pix_format {
>  #define V4L2_PIX_FMT_ARGB32  v4l2_fourcc('B', 'A', '2', '4') /* 32  ARGB=
-8-8-8-8  */
>  #define V4L2_PIX_FMT_XRGB32  v4l2_fourcc('B', 'X', '2', '4') /* 32  XRGB=
-8-8-8-8  */
> =20
> +/* RGB formats (6 or 8 bytes per pixel) */
> +#define V4L2_PIX_FMT_BGR24_12    v4l2_fourcc('B', '3', '1', '2') /* 48  =
BGR 12-bit per component */
> +
>  /* Grey formats */
>  #define V4L2_PIX_FMT_GREY    v4l2_fourcc('G', 'R', 'E', 'Y') /*  8  Grey=
scale     */
>  #define V4L2_PIX_FMT_Y4      v4l2_fourcc('Y', '0', '4', ' ') /*  4  Grey=
scale     */