media: add Mediatek's MM21 format

Add Mediatek's non-compressed 8 bit block video mode. This format is
produced by the MT8183 codec and can be converted to a non-proprietary
format by the MDP3 component.
Signed-off-by: Alexandre Courbot <acourbot@chromium.org>
Signed-off-by: Tzung-Bi Shih <tzungbi@google.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

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

@@ -238,6 +238,13 @@ please make a proposal on the linux-media mailing list.
 	It is an opaque intermediate format and the MDP hardware must be
 	used to convert ``V4L2_PIX_FMT_MT21C`` to ``V4L2_PIX_FMT_NV12M``,
 	``V4L2_PIX_FMT_YUV420M`` or ``V4L2_PIX_FMT_YVU420``.
+    * .. _V4L2-PIX-FMT-MM21:
+
+      - ``V4L2_PIX_FMT_MM21``
+      - 'MM21'
+      - Non-compressed, tiled two-planar format used by Mediatek MT8183.
+	This is an opaque intermediate format and the MDP3 hardware can be
+	used to convert it to other formats.
 
 .. raw:: latex
 

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

@@ -1348,6 +1348,7 @@ static void v4l_fill_fmtdesc(struct v4l2_fmtdesc *fmt)
 	case V4L2_PIX_FMT_TM6000:	descr = "A/V + VBI Mux Packet"; break;
 	case V4L2_PIX_FMT_CIT_YYVYUY:	descr = "GSPCA CIT YYVYUY"; break;
 	case V4L2_PIX_FMT_KONICA420:	descr = "GSPCA KONICA420"; break;
+	case V4L2_PIX_FMT_MM21:		descr = "Mediatek 8-bit Block Format"; break;
 	case V4L2_PIX_FMT_HSV24:	descr = "24-bit HSV 8-8-8"; break;
 	case V4L2_PIX_FMT_HSV32:	descr = "32-bit XHSV 8-8-8-8"; break;
 	case V4L2_SDR_FMT_CU8:		descr = "Complex U8"; break;

include/uapi/linux/videodev2.h

@@ -739,6 +739,7 @@ struct v4l2_pix_format {
 #define V4L2_PIX_FMT_Y12I     v4l2_fourcc('Y', '1', '2', 'I') /* Greyscale 12-bit L/R interleaved */
 #define V4L2_PIX_FMT_Z16      v4l2_fourcc('Z', '1', '6', ' ') /* Depth data 16-bit */
 #define V4L2_PIX_FMT_MT21C    v4l2_fourcc('M', 'T', '2', '1') /* Mediatek compressed block mode  */
+#define V4L2_PIX_FMT_MM21     v4l2_fourcc('M', 'M', '2', '1') /* Mediatek 8-bit block mode, two non-contiguous planes */
 #define V4L2_PIX_FMT_INZI     v4l2_fourcc('I', 'N', 'Z', 'I') /* Intel Planar Greyscale 10-bit and Depth 16-bit */
 #define V4L2_PIX_FMT_CNF4     v4l2_fourcc('C', 'N', 'F', '4') /* Intel 4-bit packed depth confidence information */
 #define V4L2_PIX_FMT_HI240    v4l2_fourcc('H', 'I', '2', '4') /* BTTV 8-bit dithered RGB */