media: uapi: Add a pixel format for BGR48 and RGB48

Add BGR48 and RGB48 16-bit per component image formats.
Signed-off-by: Jacopo Mondi <jacopo.mondi@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Reviewed-by: Naushir Patuck <naush@raspberrypi.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>

Documentation/userspace-api/media/v4l/pixfmt-rgb.rst

@@ -996,6 +996,60 @@ arranged in little endian order.
 
     \normalsize
 
+16 Bits Per Component
+=====================
+
+These formats store an RGB triplet in six bytes, with 16 bits per component
+stored in memory in little endian byte order. They are named based on the order
+of the RGB components as stored in memory. For instance, RGB48 stores R\
+:sub:`7:0` and R\ :sub:`15:8` in bytes 0 and 1 respectively. This differs from
+the DRM format nomenclature that instead uses the order of components as seen in
+the 48-bits little endian word.
+
+.. raw:: latex
+
+    \small
+
+.. flat-table:: RGB Formats With 16 Bits Per Component
+    :header-rows:  1
+
+    * - Identifier
+      - Code
+      - Byte 0
+      - Byte 1
+      - Byte 2
+      - Byte 3
+      - Byte 4
+      - Byte 5
+
+    * .. _V4L2-PIX-FMT-BGR48:
+
+      - ``V4L2_PIX_FMT_BGR48``
+      - 'BGR6'
+
+      - B\ :sub:`7-0`
+      - B\ :sub:`15-8`
+      - G\ :sub:`7-0`
+      - G\ :sub:`15-8`
+      - R\ :sub:`7-0`
+      - R\ :sub:`15-8`
+
+    * .. _V4L2-PIX-FMT-RGB48:
+
+      - ``V4L2_PIX_FMT_RGB48``
+      - 'RGB6'
+
+      - R\ :sub:`7-0`
+      - R\ :sub:`15-8`
+      - G\ :sub:`7-0`
+      - G\ :sub:`15-8`
+      - B\ :sub:`7-0`
+      - B\ :sub:`15-8`
+
+.. raw:: latex
+
+    \normalsize
+
 Deprecated RGB Formats
 ======================
 

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

@@ -253,6 +253,8 @@ const struct v4l2_format_info *v4l2_format_info(u32 format)
 		{ .format = V4L2_PIX_FMT_RGB555,  .pixel_enc = V4L2_PIXEL_ENC_RGB, .mem_planes = 1, .comp_planes = 1, .bpp = { 2, 0, 0, 0 }, .bpp_div = { 1, 1, 1, 1 }, .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 }, .bpp_div = { 1, 1, 1, 1 }, .hdiv = 1, .vdiv = 1 },
 		{ .format = V4L2_PIX_FMT_BGR48_12, .pixel_enc = V4L2_PIXEL_ENC_RGB, .mem_planes = 1, .comp_planes = 1, .bpp = { 6, 0, 0, 0 }, .bpp_div = { 1, 1, 1, 1 }, .hdiv = 1, .vdiv = 1 },
+		{ .format = V4L2_PIX_FMT_BGR48, .pixel_enc = V4L2_PIXEL_ENC_RGB, .mem_planes = 1, .comp_planes = 1, .bpp = { 6, 0, 0, 0 }, .bpp_div = { 1, 1, 1, 1 }, .hdiv = 1, .vdiv = 1 },
+		{ .format = V4L2_PIX_FMT_RGB48, .pixel_enc = V4L2_PIXEL_ENC_RGB, .mem_planes = 1, .comp_planes = 1, .bpp = { 6, 0, 0, 0 }, .bpp_div = { 1, 1, 1, 1 }, .hdiv = 1, .vdiv = 1 },
 		{ .format = V4L2_PIX_FMT_ABGR64_12, .pixel_enc = V4L2_PIXEL_ENC_RGB, .mem_planes = 1, .comp_planes = 1, .bpp = { 8, 0, 0, 0 }, .bpp_div = { 1, 1, 1, 1 }, .hdiv = 1, .vdiv = 1 },
 		{ .format = V4L2_PIX_FMT_RGBA1010102, .pixel_enc = V4L2_PIXEL_ENC_RGB, .mem_planes = 1, .comp_planes = 1, .bpp = { 4, 0, 0, 0 }, .bpp_div = { 1, 1, 1, 1 }, .hdiv = 1, .vdiv = 1 },
 		{ .format = V4L2_PIX_FMT_RGBX1010102, .pixel_enc = V4L2_PIXEL_ENC_RGB, .mem_planes = 1, .comp_planes = 1, .bpp = { 4, 0, 0, 0 }, .bpp_div = { 1, 1, 1, 1 }, .hdiv = 1, .vdiv = 1 },

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

@@ -1307,6 +1307,8 @@ static void v4l_fill_fmtdesc(struct v4l2_fmtdesc *fmt)
 	case V4L2_PIX_FMT_RGBX1010102:	descr = "32-bit RGBX 10-10-10-2"; break;
 	case V4L2_PIX_FMT_RGBA1010102:	descr = "32-bit RGBA 10-10-10-2"; break;
 	case V4L2_PIX_FMT_ARGB2101010:	descr = "32-bit ARGB 2-10-10-10"; break;
+	case V4L2_PIX_FMT_BGR48:	descr = "48-bit BGR 16-16-16"; break;
+	case V4L2_PIX_FMT_RGB48:	descr = "48-bit RGB 16-16-16"; break;
 	case V4L2_PIX_FMT_BGR48_12:	descr = "12-bit Depth BGR"; break;
 	case V4L2_PIX_FMT_ABGR64_12:	descr = "12-bit Depth BGRA"; break;
 	case V4L2_PIX_FMT_GREY:		descr = "8-bit Greyscale"; break;

include/uapi/linux/videodev2.h

@@ -582,6 +582,8 @@ struct v4l2_pix_format {
 
 /* RGB formats (6 or 8 bytes per pixel) */
 #define V4L2_PIX_FMT_BGR48_12    v4l2_fourcc('B', '3', '1', '2') /* 48  BGR 12-bit per component */
+#define V4L2_PIX_FMT_BGR48       v4l2_fourcc('B', 'G', 'R', '6') /* 48  BGR 16-bit per component */
+#define V4L2_PIX_FMT_RGB48       v4l2_fourcc('R', 'G', 'B', '6') /* 48  RGB 16-bit per component */
 #define V4L2_PIX_FMT_ABGR64_12   v4l2_fourcc('B', '4', '1', '2') /* 64  BGRA 12-bit per component */
 
 /* Grey formats */