media: Add YUV48_12 video format

YUV48_12 is a YUV format with 12-bits per component like YUV24,
expanded to 16bits.
Data in the 12 high bits, zeros in the 4 low bits,
arranged in little endian order.

[hverkuil: replaced a . by ,]
Signed-off-by: Ming Qian <ming.qian@nxp.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

Documentation/userspace-api/media/v4l/pixfmt-packed-yuv.rst

@@ -257,6 +257,34 @@ the second byte and Y'\ :sub:`7-0` in the third byte.
     - The padding bits contain undefined values that must be ignored by all
       applications and drivers.
 
+The next table lists the packed YUV 4:4:4 formats with 12 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, storing 1 pixel in 6 bytes.
+
+.. flat-table:: Packed YUV 4:4:4 Image Formats (12bpc)
+    :header-rows: 1
+    :stub-columns: 0
+
+    * - Identifier
+      - Code
+      - Byte 1-0
+      - Byte 3-2
+      - Byte 5-4
+      - Byte 7-6
+      - Byte 9-8
+      - Byte 11-10
+
+    * .. _V4L2-PIX-FMT-YUV48-12:
+
+      - ``V4L2_PIX_FMT_YUV48_12``
+      - 'Y312'
+
+      - Y'\ :sub:`0`
+      - Cb\ :sub:`0`
+      - Cr\ :sub:`0`
+      - Y'\ :sub:`1`
+      - Cb\ :sub:`1`
+      - Cr\ :sub:`1`
 
 4:2:2 Subsampling
 =================

drivers/media/v4l2-core/v4l2-common.c

@@ -259,6 +259,7 @@ const struct v4l2_format_info *v4l2_format_info(u32 format)
 		{ .format = V4L2_PIX_FMT_UYVY,    .pixel_enc = V4L2_PIXEL_ENC_YUV, .mem_planes = 1, .comp_planes = 1, .bpp = { 2, 0, 0, 0 }, .hdiv = 2, .vdiv = 1 },
 		{ .format = V4L2_PIX_FMT_VYUY,    .pixel_enc = V4L2_PIXEL_ENC_YUV, .mem_planes = 1, .comp_planes = 1, .bpp = { 2, 0, 0, 0 }, .hdiv = 2, .vdiv = 1 },
 		{ .format = V4L2_PIX_FMT_Y212,    .pixel_enc = V4L2_PIXEL_ENC_YUV, .mem_planes = 1, .comp_planes = 1, .bpp = { 4, 0, 0, 0 }, .hdiv = 2, .vdiv = 1 },
+		{ .format = V4L2_PIX_FMT_YUV48_12, .pixel_enc = V4L2_PIXEL_ENC_YUV, .mem_planes = 1, .comp_planes = 1, .bpp = { 6, 0, 0, 0 }, .hdiv = 1, .vdiv = 1 },
 
 		/* YUV planar formats */
 		{ .format = V4L2_PIX_FMT_NV12,    .pixel_enc = V4L2_PIXEL_ENC_YUV, .mem_planes = 1, .comp_planes = 2, .bpp = { 1, 2, 0, 0 }, .hdiv = 2, .vdiv = 2 },

drivers/media/v4l2-core/v4l2-ioctl.c

@@ -1342,6 +1342,7 @@ static void v4l_fill_fmtdesc(struct v4l2_fmtdesc *fmt)
 	case V4L2_PIX_FMT_YUV420:	descr = "Planar YUV 4:2:0"; break;
 	case V4L2_PIX_FMT_HI240:	descr = "8-bit Dithered RGB (BTTV)"; break;
 	case V4L2_PIX_FMT_M420:		descr = "YUV 4:2:0 (M420)"; break;
+	case V4L2_PIX_FMT_YUV48_12:	descr = "12-bit YUV 4:4:4 Packed"; break;
 	case V4L2_PIX_FMT_NV12:		descr = "Y/UV 4:2:0"; break;
 	case V4L2_PIX_FMT_NV21:		descr = "Y/VU 4:2:0"; break;
 	case V4L2_PIX_FMT_NV16:		descr = "Y/UV 4:2:2"; break;

include/uapi/linux/videodev2.h

@@ -621,6 +621,7 @@ struct v4l2_pix_format {
 #define V4L2_PIX_FMT_YUVA32  v4l2_fourcc('Y', 'U', 'V', 'A') /* 32  YUVA-8-8-8-8  */
 #define V4L2_PIX_FMT_YUVX32  v4l2_fourcc('Y', 'U', 'V', 'X') /* 32  YUVX-8-8-8-8  */
 #define V4L2_PIX_FMT_M420    v4l2_fourcc('M', '4', '2', '0') /* 12  YUV 4:2:0 2 lines y, 1 line uv interleaved */
+#define V4L2_PIX_FMT_YUV48_12    v4l2_fourcc('Y', '3', '1', '2') /* 48  YUV 4:4:4 12-bit per component */
 
 /*
  * YCbCr packed format. For each Y2xx format, xx bits of valid data occupy the MSBs