[PATCH 05/10] media: Add B312 video format

[Ming Qian]

B312 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.

Signed-off-by: Ming Qian <ming.qian@xxxxxxx>
---
 .../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(+)

diff --git a/Documentation/userspace-api/media/v4l/pixfmt-rgb.rst b/Documentation/userspace-api/media/v4l/pixfmt-rgb.rst
index 30f51cd33f99..f7785c93292a 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 components as seen in a 24- or
     \normalsize
 
 
+More Than 8 Bits Per Component
+==============================
+
+These formats store an RGB triplet in six or eighth bytes, with more than 8 bits per component.
+expand the bits per component to 16 bits, data in the high bits, zeros in 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-B312:
+
+      - ``V4L2_PIX_FMT_B312``
+      - 'B312'
+
+      - B\ :sub:`15-4`
+      - G\ :sub:`15-4`
+      - R\ :sub:`15-4`
+      -
+
+.. raw:: latex
+
+    \normalsize
+
 Deprecated RGB Formats
 ======================
 
diff --git a/drivers/media/v4l2-core/v4l2-common.c b/drivers/media/v4l2-core/v4l2-common.c
index 332d4b11bc1b..0cc58abae562 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 format)
 		{ .format = V4L2_PIX_FMT_RGB565,  .pixel_enc = V4L2_PIXEL_ENC_RGB, .mem_planes = 1, .comp_planes = 1, .bpp = { 2, 0, 0, 0 }, .hdiv = 1, .vdiv = 1 },
 		{ .format = V4L2_PIX_FMT_RGB555,  .pixel_enc = V4L2_PIXEL_ENC_RGB, .mem_planes = 1, .comp_planes = 1, .bpp = { 2, 0, 0, 0 }, .hdiv = 1, .vdiv = 1 },
 		{ .format = V4L2_PIX_FMT_BGR666,  .pixel_enc = V4L2_PIXEL_ENC_RGB, .mem_planes = 1, .comp_planes = 1, .bpp = { 4, 0, 0, 0 }, .hdiv = 1, .vdiv = 1 },
+		{ .format = V4L2_PIX_FMT_B312,    .pixel_enc = V4L2_PIXEL_ENC_RGB, .mem_planes = 1, .comp_planes = 1, .bpp = { 6, 0, 0, 0 }, .hdiv = 1, .vdiv = 1 },
 
 		/* YUV packed formats */
 		{ .format = V4L2_PIX_FMT_YUYV,    .pixel_enc = V4L2_PIXEL_ENC_YUV, .mem_planes = 1, .comp_planes = 1, .bpp = { 2, 0, 0, 0 }, .hdiv = 2, .vdiv = 1 },
diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c
index 5b97d7e5dbbf..8c3d40d3acf5 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 *fmt)
 	case V4L2_PIX_FMT_BGRX32:	descr = "32-bit XBGR 8-8-8-8"; break;
 	case V4L2_PIX_FMT_RGBA32:	descr = "32-bit RGBA 8-8-8-8"; break;
 	case V4L2_PIX_FMT_RGBX32:	descr = "32-bit RGBX 8-8-8-8"; break;
+	case V4L2_PIX_FMT_B312:		descr = "12-bit Depth BGR"; break;
 	case V4L2_PIX_FMT_GREY:		descr = "8-bit Greyscale"; break;
 	case V4L2_PIX_FMT_Y4:		descr = "4-bit Greyscale"; break;
 	case V4L2_PIX_FMT_Y6:		descr = "6-bit Greyscale"; break;
diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
index 3475331737af..c67f895210de 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  */
 
+/* RGB formats (6 or 8 bytes per pixel) */
+#define V4L2_PIX_FMT_B312    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  Greyscale     */
 #define V4L2_PIX_FMT_Y4      v4l2_fourcc('Y', '0', '4', ' ') /*  4  Greyscale     */
-- 
2.38.1