Re: [PATCH v3 03/10] media: Add YUYV64_12 video format

From: mirela.rabulea@xxxxxxxxxxx
Date: Mon Feb 20 2023 - 16:59:42 EST

Hi Ming,

On 20.02.2023 04:15, Ming Qian wrote:
From: Mirela Rabulea (OSS) <mirela.rabulea@xxxxxxxxxxx>
Sent: 2023年2月19日 5:52
To: Ming Qian <ming.qian@xxxxxxx>; mchehab@xxxxxxxxxx; hverkuil-
cisco@xxxxxxxxx; nicolas@xxxxxxxxxxxx
Cc: shawnguo@xxxxxxxxxx; s.hauer@xxxxxxxxxxxxxx; kernel@xxxxxxxxxxxxxx;
festevam@xxxxxxxxx; X.H. Bao <xiahong.bao@xxxxxxx>; dl-linux-imx <linux-
imx@xxxxxxx>; linux-media@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx;
devicetree@xxxxxxxxxxxxxxx; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
Subject: Re: [PATCH v3 03/10] media: Add YUYV64_12 video format

Hi,

On 14.02.2023 12:04, Ming Qian wrote:
YUYV64_12 is a YUV format with 12-bits per component like YUYV,
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>
---
.../media/v4l/pixfmt-packed-yuv.rst | 42 +++++++++++++++++++
drivers/media/v4l2-core/v4l2-common.c | 1 +
drivers/media/v4l2-core/v4l2-ioctl.c | 1 +
include/uapi/linux/videodev2.h | 1 +
4 files changed, 45 insertions(+)

diff --git
a/Documentation/userspace-api/media/v4l/pixfmt-packed-yuv.rst
b/Documentation/userspace-api/media/v4l/pixfmt-packed-yuv.rst
index bf283a1b5581..76fc331f126e 100644
--- a/Documentation/userspace-api/media/v4l/pixfmt-packed-yuv.rst
+++ b/Documentation/userspace-api/media/v4l/pixfmt-packed-yuv.rst
@@ -341,6 +341,48 @@ components horizontally by 2, storing 2 pixels in 4
bytes.

\normalsize

+The next lists the packed YUV 4:2:2 formats with more than 8 bits per
component.
+expand the bits per component to 16 bits, data in the high bits,
+zeros in the low bits, arranged in little endian order. storing 2 pixels in 8
bytes.
+
+.. raw:: latex
+
+ \footnotesize
+
+.. tabularcolumns::

+|p{3.4cm}|p{1.2cm}|p{0.8cm}|p{0.8cm}|p{0.8cm}|p{0.8cm}|p{0.8cm}|p{0.8
+cm}|p{0.8cm}|p{0.8cm}|
+
+.. flat-table:: Packed YUV 4:2:2 Formats (more than 8bpc)
+ :header-rows: 1
+ :stub-columns: 0
+
+ * - Identifier
+ - Code
+ - Byte 1-0
+ - Byte 3-2
+ - Byte 5-4
+ - Byte 7-6
+ - Byte 9-8
+ - Byte 11-10
+ - Byte 13-12
+ - Byte 15-14
+ * .. _V4L2-PIX-FMT-YUYV64-12:
+
+ - ``V4L2_PIX_FMT_YUYV64_12``
+ - 'Y212'
+
+ - Y'\ :sub:`0`
+ - Cb\ :sub:`0`
+ - Y'\ :sub:`1`
+ - Cr\ :sub:`0`
+ - Y'\ :sub:`2`
+ - Cb\ :sub:`2`
+ - Y'\ :sub:`3`
+ - Cr\ :sub:`2`
+
+.. raw:: latex
+
+ \normalsize
+
**Color Sample Location:**
Chroma samples are :ref:`interstitially sited<yuv-chroma-centered>`
horizontally.
diff --git a/drivers/media/v4l2-core/v4l2-common.c
b/drivers/media/v4l2-core/v4l2-common.c
index a5e8ba370d33..8fb1c0fa8158 100644
--- a/drivers/media/v4l2-core/v4l2-common.c
+++ b/drivers/media/v4l2-core/v4l2-common.c
@@ -258,6 +258,7 @@ const struct v4l2_format_info
*v4l2_format_info(u32 format)
{ .format = V4L2_PIX_FMT_YVYU, .pixel_enc =
V4L2_PIXEL_ENC_YUV, .mem_planes = 1, .comp_planes = 1, .bpp = { 2, 0, 0,
0 }, .hdiv = 2, .vdiv = 1 },
{ .format = V4L2_PIX_FMT_UYVY, .pixel_enc =
V4L2_PIXEL_ENC_YUV, .mem_planes = 1, .comp_planes = 1, .bpp = { 2, 0, 0,
0 }, .hdiv = 2, .vdiv = 1 },
{ .format = V4L2_PIX_FMT_VYUY, .pixel_enc =
V4L2_PIXEL_ENC_YUV, .mem_planes = 1, .comp_planes = 1, .bpp = { 2, 0, 0,
0 }, .hdiv = 2, .vdiv = 1 },
+ { .format = V4L2_PIX_FMT_YUYV64_12, .pixel_enc =
+V4L2_PIXEL_ENC_YUV, .mem_planes = 1, .comp_planes = 1, .bpp = { 4, 0,
+0, 0 }, .hdiv = 2, .vdiv = 1 },

/* YUV planar formats */
{ .format = V4L2_PIX_FMT_NV12, .pixel_enc =
V4L2_PIXEL_ENC_YUV, .mem_planes = 1, .comp_planes = 2, .bpp = { 1, 2, 0,
0 }, .hdiv = 2, .vdiv = 2 },
diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c
b/drivers/media/v4l2-core/v4l2-ioctl.c
index ec1c9ef27e88..e5002d6fe7ee 100644
--- a/drivers/media/v4l2-core/v4l2-ioctl.c
+++ b/drivers/media/v4l2-core/v4l2-ioctl.c
@@ -1343,6 +1343,7 @@ static void v4l_fill_fmtdesc(struct v4l2_fmtdesc
*fmt)
case V4L2_PIX_FMT_YUV420: descr = "Planar YUV 4:2:0"; break;
case V4L2_PIX_FMT_HI240: descr = "8-bit Dithered RGB (BTTV)";
break;
case V4L2_PIX_FMT_M420: descr = "YUV 4:2:0 (M420)";
break;
+ case V4L2_PIX_FMT_YUYV64_12: descr = "12-bit Depth YUYV
4:2:2"; break;
case V4L2_PIX_FMT_NV12: descr = "Y/UV 4:2:0"; break;
case V4L2_PIX_FMT_NV21: descr = "Y/VU 4:2:0"; break;
case V4L2_PIX_FMT_NV16: descr = "Y/UV 4:2:2"; break;
diff --git a/include/uapi/linux/videodev2.h
b/include/uapi/linux/videodev2.h index 3d8f89bff33c..3712a36d6fdf
100644
--- a/include/uapi/linux/videodev2.h
+++ b/include/uapi/linux/videodev2.h
@@ -618,6 +618,7 @@ struct v4l2_pix_format {
#define V4L2_PIX_FMT_YUVA32 v4l2_fourcc('Y', 'U', 'V', 'A') /* 32 YUVA-8-
8-8-8 */
#define V4L2_PIX_FMT_YUVX32 v4l2_fourcc('Y', 'U', 'V', 'X') /* 32 YUVX-8-
8-8-8 */
#define V4L2_PIX_FMT_M420 v4l2_fourcc('M', '4', '2', '0') /* 12 YUV 4:2:0
2 lines y, 1 line uv interleaved */
+#define V4L2_PIX_FMT_YUYV64_12 v4l2_fourcc('Y', '2', '1', '2') /* 32 YUYV
12-bit per component */

It seems Y212 is already added with the same fourcc code, causing build
errors:

drivers/media/v4l2-core/v4l2-ioctl.c: In function ‘v4l_fill_fmtdesc’:
drivers/media/v4l2-core/v4l2-ioctl.c:1455:9: error: duplicate case value
1455 | case V4L2_PIX_FMT_Y212: descr = "12-bit YUYV
Packed"; break;
| ^~~~
drivers/media/v4l2-core/v4l2-ioctl.c:1349:9: note: previously used here
1349 | case V4L2_PIX_FMT_YUYV64_12: descr = "12-bit Depth
YUYV 4:2:2"; break;
| ^~~~

Regards,
Mirela

Hi Mirela,
Would you please double check it?
The format V4L2_PIX_FMT_Y212 was added by the first version of this patchset, and it should be replaced by
V4L2_PIX_FMT_YUYV64_12 in this v3 patchset.
And I checked my patch, and my local environment, I didn't found any V4L2_PIX_FMT_Y212, and I didn't meet this build error

Ming

I applied the _v3 version of the patches over linux-next, and the build error comes from conflicting definition of the fourcc
#define V4L2_PIX_FMT_YUYV64_12 v4l2_fourcc('Y', '2', '1', '2') /* 32 YUYV 12-bit per component */

with this patch, which adds:
+#define V4L2_PIX_FMT_Y212 v4l2_fourcc('Y', '2', '1', '2') /* 32 YUYV 4:2:2 */

commit 0dc1d7a79a8d13e316d3b168e9fc57e376099c7a
Author: Tomi Valkeinen <tomi.valkeinen+renesas@xxxxxxxxxxxxxxxx>
Date: Wed Dec 21 11:24:43 2022 +0200

media: Add Y210, Y212 and Y216 formats

Add Y210, Y212 and Y216 formats.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen+renesas@xxxxxxxxxxxxxxxx>
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@xxxxxxxxxxxxxxxx>
Acked-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxx>
Acked-by: Hans Verkuil <hverkuil-cisco@xxxxxxxxx>
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@xxxxxxxxxxxxxxxx>

https://patchwork.kernel.org/project/linux-media/patch/20221219140139.294245-3-tomi.valkeinen+renesas@xxxxxxxxxxxxxxxx/

In this case, matching the formats defined in DRM was the stronger argument for the format naming scheme.

Regards,
Mirela



/* two planes -- one Y, one Cr + Cb interleaved */
#define V4L2_PIX_FMT_NV12 v4l2_fourcc('N', 'V', '1', '2') /* 12 Y/CbCr
4:2:0 */