[PATCH v4 02/10] media: Add Y012 video format

From: Ming Qian
Date: Tue Mar 14 2023 - 06:11:15 EST


Y012 is a luma-only formats with 12-bits per pixel,
expanded to 16bits.
Data in the 12 high bits, zeros in the 4 low bits,
arranged in little endian order.

Signed-off-by: Ming Qian <ming.qian@xxxxxxx>
---
.../userspace-api/media/v4l/pixfmt-yuv-luma.rst | 15 +++++++++++++++
drivers/media/v4l2-core/v4l2-ioctl.c | 1 +
include/uapi/linux/videodev2.h | 1 +
3 files changed, 17 insertions(+)

diff --git a/Documentation/userspace-api/media/v4l/pixfmt-yuv-luma.rst b/Documentation/userspace-api/media/v4l/pixfmt-yuv-luma.rst
index 62078a01de76..7888151f2cd4 100644
--- a/Documentation/userspace-api/media/v4l/pixfmt-yuv-luma.rst
+++ b/Documentation/userspace-api/media/v4l/pixfmt-yuv-luma.rst
@@ -103,6 +103,17 @@ are often referred to as greyscale formats.
- ...
- ...

+ * .. _V4L2-PIX-FMT-Y012:
+
+ - ``V4L2_PIX_FMT_Y012``
+ - 'Y012'
+
+ - Y'\ :sub:`0`\ [3:0] `0000`
+ - Y'\ :sub:`0`\ [11:4]
+ - ...
+ - ...
+ - ...
+
* .. _V4L2-PIX-FMT-Y14:

- ``V4L2_PIX_FMT_Y14``
@@ -146,3 +157,7 @@ are often referred to as greyscale formats.
than 16 bits. For example, 10 bits per pixel uses values in the range 0 to
1023. For the IPU3_Y10 format 25 pixels are packed into 32 bytes, which
leaves the 6 most significant bits of the last byte padded with 0.
+
+ For Y012 and Y12 formats, Y012 place its data in the 12 high bits, with
+ padding zeros in the 4 low bits, in contrast to Y12 format, which have
+ its padding located in the most significant bits of the 16 bit word.
diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c
index 6489b67babfa..2cb485643562 100644
--- a/drivers/media/v4l2-core/v4l2-ioctl.c
+++ b/drivers/media/v4l2-core/v4l2-ioctl.c
@@ -1307,6 +1307,7 @@ 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_Y012: 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;
diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
index f83a9d1210fb..db06d4c4f008 100644
--- a/include/uapi/linux/videodev2.h
+++ b/include/uapi/linux/videodev2.h
@@ -586,6 +586,7 @@ 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_Y012 v4l2_fourcc('Y', '0', '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 */
--
2.38.1