media: v4l: Add 1X16 16-bit greyscale media bus code definition

This extends the greyscale media bus family originally from
MEDIA_BUS_FMT_Y8_1X8 up to MEDIA_BUS_FMT_Y14_1X14 by adding
MEDIA_BUS_FMT_Y16_1X16, and behaves the same way with 16 bits.
Add its documentation in subdev-formats.rst

Signed-off-by: Benjamin Mugnier <benjamin.mugnier@foss.st.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>

Documentation/userspace-api/media/v4l/subdev-formats.rst

@@ -6057,6 +6057,43 @@ the following codes.
       - y\ :sub:`2`
       - y\ :sub:`1`
       - y\ :sub:`0`
+    * .. _MEDIA-BUS-FMT-Y16-1X16:
+
+      - MEDIA_BUS_FMT_Y16_1X16
+      - 0x202e
+      -
+      -
+      -
+      -
+      -
+      -
+      -
+      -
+      -
+      -
+      -
+      -
+      -
+      -
+      -
+      -
+      -
+      - y\ :sub:`15`
+      - y\ :sub:`14`
+      - y\ :sub:`13`
+      - y\ :sub:`12`
+      - y\ :sub:`11`
+      - y\ :sub:`10`
+      - y\ :sub:`9`
+      - y\ :sub:`8`
+      - y\ :sub:`7`
+      - y\ :sub:`6`
+      - y\ :sub:`5`
+      - y\ :sub:`4`
+      - y\ :sub:`3`
+      - y\ :sub:`2`
+      - y\ :sub:`1`
+      - y\ :sub:`0`
     * .. _MEDIA-BUS-FMT-UYVY8-1X16:
 
       - MEDIA_BUS_FMT_UYVY8_1X16

include/uapi/linux/media-bus-format.h

@@ -69,7 +69,7 @@
 #define MEDIA_BUS_FMT_RGB121212_1X36		0x1019
 #define MEDIA_BUS_FMT_RGB161616_1X48		0x101a
 
-/* YUV (including grey) - next is	0x202e */
+/* YUV (including grey) - next is	0x202f */
 #define MEDIA_BUS_FMT_Y8_1X8			0x2001
 #define MEDIA_BUS_FMT_UV8_1X8			0x2015
 #define MEDIA_BUS_FMT_UYVY8_1_5X8		0x2002
@@ -92,6 +92,7 @@
 #define MEDIA_BUS_FMT_YUYV12_2X12		0x201e
 #define MEDIA_BUS_FMT_YVYU12_2X12		0x201f
 #define MEDIA_BUS_FMT_Y14_1X14			0x202d
+#define MEDIA_BUS_FMT_Y16_1X16			0x202e
 #define MEDIA_BUS_FMT_UYVY8_1X16		0x200f
 #define MEDIA_BUS_FMT_VYUY8_1X16		0x2010
 #define MEDIA_BUS_FMT_YUYV8_1X16		0x2011