media: v4l: Add 14-bit raw greyscale pixel format

The new format is called V4L2_PIX_FMT_Y14. Like V4L2_PIX_FMT_Y10 and
V4L2_PIX_FMT_Y12 it is stored in two bytes per pixel but has only two
unused bits at the top.
Signed-off-by: Daniel Glöckner <dg@emlix.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

Documentation/media/uapi/v4l/pixfmt-y14.rst

+.. Permission is granted to copy, distribute and/or modify this
+.. document under the terms of the GNU Free Documentation License,
+.. Version 1.1 or any later version published by the Free Software
+.. Foundation, with no Invariant Sections, no Front-Cover Texts
+.. and no Back-Cover Texts. A copy of the license is included at
+.. Documentation/media/uapi/fdl-appendix.rst.
+..
+.. TODO: replace it to GFDL-1.1-or-later WITH no-invariant-sections
+
+.. _V4L2-PIX-FMT-Y14:
+
+*************************
+V4L2_PIX_FMT_Y14 ('Y14 ')
+*************************
+
+
+Grey-scale image
+
+
+Description
+===========
+
+This is a grey-scale image with a depth of 14 bits per pixel. Pixels are
+stored in 16-bit words with unused high bits padded with 0. The least
+significant byte is stored at lower memory addresses (little-endian).
+
+**Byte Order.**
+Each cell is one byte.
+
+
+
+
+.. flat-table::
+    :header-rows:  0
+    :stub-columns: 0
+
+    * - start + 0:
+      - Y'\ :sub:`00low`
+      - Y'\ :sub:`00high`
+      - Y'\ :sub:`01low`
+      - Y'\ :sub:`01high`
+      - Y'\ :sub:`02low`
+      - Y'\ :sub:`02high`
+      - Y'\ :sub:`03low`
+      - Y'\ :sub:`03high`
+    * - start + 8:
+      - Y'\ :sub:`10low`
+      - Y'\ :sub:`10high`
+      - Y'\ :sub:`11low`
+      - Y'\ :sub:`11high`
+      - Y'\ :sub:`12low`
+      - Y'\ :sub:`12high`
+      - Y'\ :sub:`13low`
+      - Y'\ :sub:`13high`
+    * - start + 16:
+      - Y'\ :sub:`20low`
+      - Y'\ :sub:`20high`
+      - Y'\ :sub:`21low`
+      - Y'\ :sub:`21high`
+      - Y'\ :sub:`22low`
+      - Y'\ :sub:`22high`
+      - Y'\ :sub:`23low`
+      - Y'\ :sub:`23high`
+    * - start + 24:
+      - Y'\ :sub:`30low`
+      - Y'\ :sub:`30high`
+      - Y'\ :sub:`31low`
+      - Y'\ :sub:`31high`
+      - Y'\ :sub:`32low`
+      - Y'\ :sub:`32high`
+      - Y'\ :sub:`33low`
+      - Y'\ :sub:`33high`

Documentation/media/uapi/v4l/yuv-formats.rst

@@ -35,6 +35,7 @@ to brightness information.
     pixfmt-grey
     pixfmt-y10
     pixfmt-y12
+    pixfmt-y14
     pixfmt-y10b
     pixfmt-y10p
     pixfmt-y16

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

@@ -1222,6 +1222,7 @@ static void v4l_fill_fmtdesc(struct v4l2_fmtdesc *fmt)
 	case V4L2_PIX_FMT_Y6:		descr = "6-bit Greyscale"; break;
 	case V4L2_PIX_FMT_Y10:		descr = "10-bit Greyscale"; break;
 	case V4L2_PIX_FMT_Y12:		descr = "12-bit Greyscale"; break;
+	case V4L2_PIX_FMT_Y14:		descr = "14-bit Greyscale"; break;
 	case V4L2_PIX_FMT_Y16:		descr = "16-bit Greyscale"; break;
 	case V4L2_PIX_FMT_Y16_BE:	descr = "16-bit Greyscale BE"; break;
 	case V4L2_PIX_FMT_Y10BPACK:	descr = "10-bit Greyscale (Packed)"; break;

include/uapi/linux/videodev2.h

@@ -565,6 +565,7 @@ struct v4l2_pix_format {
 #define V4L2_PIX_FMT_Y6      v4l2_fourcc('Y', '0', '6', ' ') /*  6  Greyscale     */
 #define V4L2_PIX_FMT_Y10     v4l2_fourcc('Y', '1', '0', ' ') /* 10  Greyscale     */
 #define V4L2_PIX_FMT_Y12     v4l2_fourcc('Y', '1', '2', ' ') /* 12  Greyscale     */
+#define V4L2_PIX_FMT_Y14     v4l2_fourcc('Y', '1', '4', ' ') /* 14  Greyscale     */
 #define V4L2_PIX_FMT_Y16     v4l2_fourcc('Y', '1', '6', ' ') /* 16  Greyscale     */
 #define V4L2_PIX_FMT_Y16_BE  v4l2_fourcc_be('Y', '1', '6', ' ') /* 16  Greyscale BE  */