[RFC PATCH v4 01/12] media: v4l: Add V4L2-PIX-FMT-Y12P format

[Jean-Michel Hautbois]

This is a packed grey-scale image format with a depth of 12 bits per
pixel. Two consecutive pixels are packed into 3 bytes. The first 2 bytes
contain the 8 high order bits of the pixels, and the 3rd byte contains
the 4 least significants bits of each pixel, in the same order.

Add the entry in userspace API, and document it.

Signed-off-by: Jean-Michel Hautbois <jeanmichel.hautbois at ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
---
 .../userspace-api/media/v4l/pixfmt-yuv-luma.rst       | 11 +++++++++++
 drivers/media/v4l2-core/v4l2-ioctl.c                  |  1 +
 include/uapi/linux/videodev2.h                        |  1 +
 3 files changed, 13 insertions(+)

diff --git a/Documentation/userspace-api/media/v4l/pixfmt-yuv-luma.rst b/Documentation/userspace-api/media/v4l/pixfmt-yuv-luma.rst
index 91942c4f0967..2d9d588eedcd 100644
--- a/Documentation/userspace-api/media/v4l/pixfmt-yuv-luma.rst
+++ b/Documentation/userspace-api/media/v4l/pixfmt-yuv-luma.rst
@@ -92,6 +92,17 @@ are often referred to as greyscale formats.
       - ...
       - ...
 
+    * .. _V4L2-PIX-FMT-Y12P:
+
+      - ``V4L2_PIX_FMT_Y12P``
+      - 'Y12P'
+
+      - Y'\ :sub:`0`\ [11:4]
+      - Y'\ :sub:`1`\ [11:4]
+      - Y'\ :sub:`1`\ [3:0] Y'\ :sub:`0`\ [3:0]
+      - ...
+      - ...
+
     * .. _V4L2-PIX-FMT-Y14:
 
       - ``V4L2_PIX_FMT_Y14``
diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c
index cca67d43a62f..64a72a6b2132 100644
--- a/drivers/media/v4l2-core/v4l2-ioctl.c
+++ b/drivers/media/v4l2-core/v4l2-ioctl.c
@@ -1264,6 +1264,7 @@ static void v4l_fill_fmtdesc(struct v4l2_fmtdesc *fmt)
 	case V4L2_PIX_FMT_Y16_BE:	descr = "16-bit Greyscale BE"; break;
 	case V4L2_PIX_FMT_Y10BPACK:	descr = "10-bit Greyscale (Packed)"; break;
 	case V4L2_PIX_FMT_Y10P:		descr = "10-bit Greyscale (MIPI Packed)"; break;
+	case V4L2_PIX_FMT_Y12P:		descr = "12-bit Greyscale (MIPI Packed)"; break;
 	case V4L2_PIX_FMT_Y8I:		descr = "Interleaved 8-bit Greyscale"; break;
 	case V4L2_PIX_FMT_Y12I:		descr = "Interleaved 12-bit Greyscale"; break;
 	case V4L2_PIX_FMT_Z16:		descr = "16-bit Depth"; break;
diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
index c9ee5de1bce6..bef488205fea 100644
--- a/include/uapi/linux/videodev2.h
+++ b/include/uapi/linux/videodev2.h
@@ -569,6 +569,7 @@ struct v4l2_pix_format {
 /* Grey bit-packed formats */
 #define V4L2_PIX_FMT_Y10BPACK    v4l2_fourcc('Y', '1', '0', 'B') /* 10  Greyscale bit-packed */
 #define V4L2_PIX_FMT_Y10P    v4l2_fourcc('Y', '1', '0', 'P') /* 10  Greyscale, MIPI RAW10 packed */
+#define V4L2_PIX_FMT_Y12P    v4l2_fourcc('Y', '1', '2', 'P') /* 12  Greyscale, MIPI RAW12 packed */
 
 /* Palette formats */
 #define V4L2_PIX_FMT_PAL8    v4l2_fourcc('P', 'A', 'L', '8') /*  8  8-bit palette */
-- 
2.32.0