From: Sakari Ailus <sakari.ailus@linux.intel.com>
To: linux-media@vger.kernel.org
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>,
tomi.valkeinen@ideasonboard.com, bingbu.cao@intel.com,
hongju.wang@intel.com, hverkuil@xs4all.nl,
Andrey Konovalov <andrey.konovalov@linaro.org>,
Jacopo Mondi <jacopo.mondi@ideasonboard.com>,
Dmitry Perchanov <dmitry.perchanov@intel.com>,
"Ng, Khai Wen" <khai.wen.ng@intel.com>,
Alain Volmat <alain.volmat@foss.st.com>
Subject: [PATCH v2.1 05/14] media: uapi: v4l: Add generic 8-bit metadata format definitions
Date: Fri, 26 Apr 2024 11:05:47 +0300 [thread overview]
Message-ID: <20240426080547.938404-1-sakari.ailus@linux.intel.com> (raw)
In-Reply-To: <20240425212711.928300-6-sakari.ailus@linux.intel.com>
Generic 8-bit metadata formats define the in-memory data layout but not
the format of the data itself. The reasoning for having such formats is to
allow CSI-2 receiver drivers to receive and DMA drivers to write the data
to memory without knowing a large number of device-specific formats.
These formats may be used only in conjunction with a Media Controller
pipeline where the internal pad of the source sub-device defines the
specific format of the data (using an mbus code).
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
---
since v2:
- Remove the sentence on internal pads, including the cross reference. It
will be reintroduced later on separately.
.../userspace-api/media/v4l/dev-subdev.rst | 2 +
.../userspace-api/media/v4l/meta-formats.rst | 3 +-
.../media/v4l/metafmt-generic.rst | 340 ++++++++++++++++++
drivers/media/v4l2-core/v4l2-ioctl.c | 7 +
include/uapi/linux/videodev2.h | 8 +
5 files changed, 359 insertions(+), 1 deletion(-)
create mode 100644 Documentation/userspace-api/media/v4l/metafmt-generic.rst
diff --git a/Documentation/userspace-api/media/v4l/dev-subdev.rst b/Documentation/userspace-api/media/v4l/dev-subdev.rst
index 43988516acdd..f375b820ab68 100644
--- a/Documentation/userspace-api/media/v4l/dev-subdev.rst
+++ b/Documentation/userspace-api/media/v4l/dev-subdev.rst
@@ -506,6 +506,8 @@ source pads.
subdev-formats
+.. _subdev-routing:
+
Streams, multiplexed media pads and internal routing
----------------------------------------------------
diff --git a/Documentation/userspace-api/media/v4l/meta-formats.rst b/Documentation/userspace-api/media/v4l/meta-formats.rst
index 0bb61fc5bc00..c23aac823d2c 100644
--- a/Documentation/userspace-api/media/v4l/meta-formats.rst
+++ b/Documentation/userspace-api/media/v4l/meta-formats.rst
@@ -13,9 +13,10 @@ These formats are used for the :ref:`metadata` interface only.
:maxdepth: 1
metafmt-d4xx
+ metafmt-generic
metafmt-intel-ipu3
metafmt-rkisp1
metafmt-uvc
+ metafmt-vivid
metafmt-vsp1-hgo
metafmt-vsp1-hgt
- metafmt-vivid
diff --git a/Documentation/userspace-api/media/v4l/metafmt-generic.rst b/Documentation/userspace-api/media/v4l/metafmt-generic.rst
new file mode 100644
index 000000000000..72b1d0b3fee6
--- /dev/null
+++ b/Documentation/userspace-api/media/v4l/metafmt-generic.rst
@@ -0,0 +1,340 @@
+.. SPDX-License-Identifier: GPL-2.0 OR GFDL-1.1-no-invariants-or-later
+
+********************************************************************************************************************************************************************************************************************************************************************************
+V4L2_META_FMT_GENERIC_8 ('MET8'), V4L2_META_FMT_GENERIC_CSI2_10 ('MC1A'), V4L2_META_FMT_GENERIC_CSI2_12 ('MC1C'), V4L2_META_FMT_GENERIC_CSI2_14 ('MC1E'), V4L2_META_FMT_GENERIC_CSI2_16 ('MC1G'), V4L2_META_FMT_GENERIC_CSI2_20 ('MC1K'), V4L2_META_FMT_GENERIC_CSI2_24 ('MC1O')
+********************************************************************************************************************************************************************************************************************************************************************************
+
+
+Generic line-based metadata formats
+
+
+Description
+===========
+
+These generic line-based metadata formats define the memory layout of the data
+without defining the format or meaning of the metadata itself.
+
+.. _v4l2-meta-fmt-generic-8:
+
+V4L2_META_FMT_GENERIC_8
+-----------------------
+
+The V4L2_META_FMT_GENERIC_8 format is a plain 8-bit metadata format. This format
+is used on CSI-2 for 8 bits per :ref:`Data Unit <media-glossary-data-unit>`.
+
+Additionally it is used for 16 bits per Data Unit when two bytes of metadata are
+packed into one 16-bit Data Unit. Otherwise the 16 bits per pixel dataformat is
+:ref:`V4L2_META_FMT_GENERIC_CSI2_16 <v4l2-meta-fmt-generic-csi2-16>`.
+
+**Byte Order Of V4L2_META_FMT_GENERIC_8.**
+Each cell is one byte. "M" denotes a byte of metadata.
+
+.. tabularcolumns:: |p{2.4cm}|p{1.2cm}|p{1.2cm}|p{1.2cm}|p{1.2cm}|
+
+.. flat-table:: Sample 4x2 Metadata Frame
+ :header-rows: 0
+ :stub-columns: 0
+ :widths: 12 8 8 8 8
+
+ * - start + 0:
+ - M\ :sub:`00`
+ - M\ :sub:`10`
+ - M\ :sub:`20`
+ - M\ :sub:`30`
+ * - start + 4:
+ - M\ :sub:`01`
+ - M\ :sub:`11`
+ - M\ :sub:`21`
+ - M\ :sub:`31`
+
+.. _v4l2-meta-fmt-generic-csi2-10:
+
+V4L2_META_FMT_GENERIC_CSI2_10
+-----------------------------
+
+V4L2_META_FMT_GENERIC_CSI2_10 contains 8-bit generic metadata packed in 10-bit
+Data Units, with one padding byte after every four bytes of metadata. This
+format is typically used by CSI-2 receivers with a source that transmits
+MEDIA_BUS_FMT_META_10 and the CSI-2 receiver writes the received data to memory
+as-is.
+
+The packing of the data follows the MIPI CSI-2 specification and the padding of
+the data is defined in the MIPI CCS specification.
+
+This format is also used in conjunction with 20 bits per :ref:`Data Unit
+<media-glossary-data-unit>` formats that pack two bytes of metadata into one
+Data Unit. Otherwise the 20 bits per pixel dataformat is
+:ref:`V4L2_META_FMT_GENERIC_CSI2_20 <v4l2-meta-fmt-generic-csi2-20>`.
+
+This format is little endian.
+
+**Byte Order Of V4L2_META_FMT_GENERIC_CSI2_10.**
+Each cell is one byte. "M" denotes a byte of metadata and "x" a byte of padding.
+
+.. tabularcolumns:: |p{2.4cm}|p{1.2cm}|p{1.2cm}|p{1.2cm}|p{1.2cm}|p{.8cm}|
+
+.. flat-table:: Sample 4x2 Metadata Frame
+ :header-rows: 0
+ :stub-columns: 0
+ :widths: 12 8 8 8 8 8
+
+ * - start + 0:
+ - M\ :sub:`00`
+ - M\ :sub:`10`
+ - M\ :sub:`20`
+ - M\ :sub:`30`
+ - x
+ * - start + 5:
+ - M\ :sub:`01`
+ - M\ :sub:`11`
+ - M\ :sub:`21`
+ - M\ :sub:`31`
+ - x
+
+.. _v4l2-meta-fmt-generic-csi2-12:
+
+V4L2_META_FMT_GENERIC_CSI2_12
+-----------------------------
+
+V4L2_META_FMT_GENERIC_CSI2_12 contains 8-bit generic metadata packed in 12-bit
+Data Units, with one padding byte after every two bytes of metadata. This format
+is typically used by CSI-2 receivers with a source that transmits
+MEDIA_BUS_FMT_META_12 and the CSI-2 receiver writes the received data to memory
+as-is.
+
+The packing of the data follows the MIPI CSI-2 specification and the padding of
+the data is defined in the MIPI CCS specification.
+
+This format is also used in conjunction with 24 bits per :ref:`Data Unit
+<media-glossary-data-unit>` formats that pack two bytes of metadata into one
+Data Unit. Otherwise the 24 bits per pixel dataformat is
+:ref:`V4L2_META_FMT_GENERIC_CSI2_24 <v4l2-meta-fmt-generic-csi2-24>`.
+
+This format is little endian.
+
+**Byte Order Of V4L2_META_FMT_GENERIC_CSI2_12.**
+Each cell is one byte. "M" denotes a byte of metadata and "x" a byte of padding.
+
+.. tabularcolumns:: |p{2.4cm}|p{1.2cm}|p{1.2cm}|p{1.2cm}|p{1.2cm}|p{.8cm}|p{.8cm}|
+
+.. flat-table:: Sample 4x2 Metadata Frame
+ :header-rows: 0
+ :stub-columns: 0
+ :widths: 12 8 8 8 8 8 8
+
+ * - start + 0:
+ - M\ :sub:`00`
+ - M\ :sub:`10`
+ - x
+ - M\ :sub:`20`
+ - M\ :sub:`30`
+ - x
+ * - start + 6:
+ - M\ :sub:`01`
+ - M\ :sub:`11`
+ - x
+ - M\ :sub:`21`
+ - M\ :sub:`31`
+ - x
+
+.. _v4l2-meta-fmt-generic-csi2-14:
+
+V4L2_META_FMT_GENERIC_CSI2_14
+-----------------------------
+
+V4L2_META_FMT_GENERIC_CSI2_14 contains 8-bit generic metadata packed in 14-bit
+Data Units, with three padding bytes after every four bytes of metadata. This
+format is typically used by CSI-2 receivers with a source that transmits
+MEDIA_BUS_FMT_META_14 and the CSI-2 receiver writes the received data to memory
+as-is.
+
+The packing of the data follows the MIPI CSI-2 specification and the padding of
+the data is defined in the MIPI CCS specification.
+
+This format is little endian.
+
+**Byte Order Of V4L2_META_FMT_GENERIC_CSI2_14.**
+Each cell is one byte. "M" denotes a byte of metadata and "x" a byte of padding.
+
+.. tabularcolumns:: |p{2.4cm}|p{1.2cm}|p{1.2cm}|p{1.2cm}|p{1.2cm}|p{.8cm}|p{.8cm}|p{.8cm}|
+
+.. flat-table:: Sample 4x2 Metadata Frame
+ :header-rows: 0
+ :stub-columns: 0
+ :widths: 12 8 8 8 8 8 8 8
+
+ * - start + 0:
+ - M\ :sub:`00`
+ - M\ :sub:`10`
+ - M\ :sub:`20`
+ - M\ :sub:`30`
+ - x
+ - x
+ - x
+ * - start + 7:
+ - M\ :sub:`01`
+ - M\ :sub:`11`
+ - M\ :sub:`21`
+ - M\ :sub:`31`
+ - x
+ - x
+ - x
+
+.. _v4l2-meta-fmt-generic-csi2-16:
+
+V4L2_META_FMT_GENERIC_CSI2_16
+-----------------------------
+
+V4L2_META_FMT_GENERIC_CSI2_16 contains 8-bit generic metadata packed in 16-bit
+Data Units, with one padding byte after every byte of metadata. This format is
+typically used by CSI-2 receivers with a source that transmits
+MEDIA_BUS_FMT_META_16 and the CSI-2 receiver writes the received data to memory
+as-is.
+
+The packing of the data follows the MIPI CSI-2 specification and the padding of
+the data is defined in the MIPI CCS specification.
+
+Some devices support more efficient packing of metadata in conjunction with
+16-bit image data. In that case the dataformat is
+:ref:`V4L2_META_FMT_GENERIC_8 <v4l2-meta-fmt-generic-8>`.
+
+This format is little endian.
+
+**Byte Order Of V4L2_META_FMT_GENERIC_CSI2_16.**
+Each cell is one byte. "M" denotes a byte of metadata and "x" a byte of padding.
+
+.. tabularcolumns:: |p{2.4cm}|p{1.2cm}|p{.8cm}|p{1.2cm}|p{.8cm}|p{1.2cm}|p{.8cm}|p{1.2cm}|p{.8cm}|
+
+.. flat-table:: Sample 4x2 Metadata Frame
+ :header-rows: 0
+ :stub-columns: 0
+ :widths: 12 8 8 8 8 8 8 8 8
+
+ * - start + 0:
+ - M\ :sub:`00`
+ - x
+ - M\ :sub:`10`
+ - x
+ - M\ :sub:`20`
+ - x
+ - M\ :sub:`30`
+ - x
+ * - start + 8:
+ - M\ :sub:`01`
+ - x
+ - M\ :sub:`11`
+ - x
+ - M\ :sub:`21`
+ - x
+ - M\ :sub:`31`
+ - x
+
+.. _v4l2-meta-fmt-generic-csi2-20:
+
+V4L2_META_FMT_GENERIC_CSI2_20
+-----------------------------
+
+V4L2_META_FMT_GENERIC_CSI2_20 contains 8-bit generic metadata packed in 20-bit
+Data Units, with alternating one or two padding bytes after every byte of
+metadata. This format is typically used by CSI-2 receivers with a source that
+transmits MEDIA_BUS_FMT_META_20 and the CSI-2 receiver writes the received data
+to memory as-is.
+
+The packing of the data follows the MIPI CSI-2 specification and the padding of
+the data is defined in the MIPI CCS specification.
+
+Some devices support more efficient packing of metadata in conjunction with
+16-bit image data. In that case the dataformat is
+:ref:`V4L2_META_FMT_GENERIC_CSI2_10 <v4l2-meta-fmt-generic-csi2-10>`.
+
+This format is little endian.
+
+**Byte Order Of V4L2_META_FMT_GENERIC_CSI2_20.**
+Each cell is one byte. "M" denotes a byte of metadata and "x" a byte of padding.
+
+.. tabularcolumns:: |p{2.4cm}|p{1.2cm}|p{.8cm}|p{1.2cm}|p{.8cm}|p{.8cm}|p{1.2cm}|p{.8cm}|p{1.2cm}|p{.8cm}|p{.8cm}|
+
+.. flat-table:: Sample 4x2 Metadata Frame
+ :header-rows: 0
+ :stub-columns: 0
+ :widths: 12 8 8 8 8 8 8 8 8 8 8
+
+ * - start + 0:
+ - M\ :sub:`00`
+ - x
+ - M\ :sub:`10`
+ - x
+ - x
+ - M\ :sub:`20`
+ - x
+ - M\ :sub:`30`
+ - x
+ - x
+ * - start + 10:
+ - M\ :sub:`01`
+ - x
+ - M\ :sub:`11`
+ - x
+ - x
+ - M\ :sub:`21`
+ - x
+ - M\ :sub:`31`
+ - x
+ - x
+
+.. _v4l2-meta-fmt-generic-csi2-24:
+
+V4L2_META_FMT_GENERIC_CSI2_24
+-----------------------------
+
+V4L2_META_FMT_GENERIC_CSI2_24 contains 8-bit generic metadata packed in 24-bit
+Data Units, with two padding bytes after every byte of metadata. This format is
+typically used by CSI-2 receivers with a source that transmits
+MEDIA_BUS_FMT_META_24 and the CSI-2 receiver writes the received data to memory
+as-is.
+
+The packing of the data follows the MIPI CSI-2 specification and the padding of
+the data is defined in the MIPI CCS specification.
+
+Some devices support more efficient packing of metadata in conjunction with
+16-bit image data. In that case the dataformat is
+:ref:`V4L2_META_FMT_GENERIC_CSI2_12 <v4l2-meta-fmt-generic-csi2-12>`.
+
+This format is little endian.
+
+**Byte Order Of V4L2_META_FMT_GENERIC_CSI2_24.**
+Each cell is one byte. "M" denotes a byte of metadata and "x" a byte of padding.
+
+.. tabularcolumns:: |p{2.4cm}|p{1.2cm}|p{.8cm}|p{.8cm}|p{1.2cm}|p{.8cm}|p{.8cm}|p{1.2cm}|p{.8cm}|p{.8cm}|p{1.2cm}|p{.8cm}|p{.8cm}|
+
+.. flat-table:: Sample 4x2 Metadata Frame
+ :header-rows: 0
+ :stub-columns: 0
+ :widths: 12 8 8 8 8 8 8 8 8 8 8 8 8
+
+ * - start + 0:
+ - M\ :sub:`00`
+ - x
+ - x
+ - M\ :sub:`10`
+ - x
+ - x
+ - M\ :sub:`20`
+ - x
+ - x
+ - M\ :sub:`30`
+ - x
+ - x
+ * - start + 12:
+ - M\ :sub:`01`
+ - x
+ - x
+ - M\ :sub:`11`
+ - x
+ - x
+ - M\ :sub:`21`
+ - x
+ - x
+ - M\ :sub:`31`
+ - x
+ - x
diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c
index 5aeff5519407..ae2dca7f2817 100644
--- a/drivers/media/v4l2-core/v4l2-ioctl.c
+++ b/drivers/media/v4l2-core/v4l2-ioctl.c
@@ -1460,6 +1460,13 @@ static void v4l_fill_fmtdesc(struct v4l2_fmtdesc *fmt)
case V4L2_PIX_FMT_Y210: descr = "10-bit YUYV Packed"; break;
case V4L2_PIX_FMT_Y212: descr = "12-bit YUYV Packed"; break;
case V4L2_PIX_FMT_Y216: descr = "16-bit YUYV Packed"; break;
+ case V4L2_META_FMT_GENERIC_8: descr = "8-bit Generic Metadata"; break;
+ case V4L2_META_FMT_GENERIC_CSI2_10: descr = "8-bit Generic Meta, 10b CSI-2"; break;
+ case V4L2_META_FMT_GENERIC_CSI2_12: descr = "8-bit Generic Meta, 12b CSI-2"; break;
+ case V4L2_META_FMT_GENERIC_CSI2_14: descr = "8-bit Generic Meta, 14b CSI-2"; break;
+ case V4L2_META_FMT_GENERIC_CSI2_16: descr = "8-bit Generic Meta, 16b CSI-2"; break;
+ case V4L2_META_FMT_GENERIC_CSI2_20: descr = "8-bit Generic Meta, 20b CSI-2"; break;
+ case V4L2_META_FMT_GENERIC_CSI2_24: descr = "8-bit Generic Meta, 24b CSI-2"; break;
default:
/* Compressed formats */
diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
index bf12860d570a..0f44b8486ea8 100644
--- a/include/uapi/linux/videodev2.h
+++ b/include/uapi/linux/videodev2.h
@@ -839,6 +839,14 @@ struct v4l2_pix_format {
#define V4L2_META_FMT_RK_ISP1_PARAMS v4l2_fourcc('R', 'K', '1', 'P') /* Rockchip ISP1 3A Parameters */
#define V4L2_META_FMT_RK_ISP1_STAT_3A v4l2_fourcc('R', 'K', '1', 'S') /* Rockchip ISP1 3A Statistics */
+#define V4L2_META_FMT_GENERIC_8 v4l2_fourcc('M', 'E', 'T', '8') /* Generic 8-bit metadata */
+#define V4L2_META_FMT_GENERIC_CSI2_10 v4l2_fourcc('M', 'C', '1', 'A') /* 10-bit CSI-2 packed 8-bit metadata */
+#define V4L2_META_FMT_GENERIC_CSI2_12 v4l2_fourcc('M', 'C', '1', 'C') /* 12-bit CSI-2 packed 8-bit metadata */
+#define V4L2_META_FMT_GENERIC_CSI2_14 v4l2_fourcc('M', 'C', '1', 'E') /* 14-bit CSI-2 packed 8-bit metadata */
+#define V4L2_META_FMT_GENERIC_CSI2_16 v4l2_fourcc('M', 'C', '1', 'G') /* 16-bit CSI-2 packed 8-bit metadata */
+#define V4L2_META_FMT_GENERIC_CSI2_20 v4l2_fourcc('M', 'C', '1', 'K') /* 20-bit CSI-2 packed 8-bit metadata */
+#define V4L2_META_FMT_GENERIC_CSI2_24 v4l2_fourcc('M', 'C', '1', 'O') /* 24-bit CSI-2 packed 8-bit metadata */
+
/* priv field value to indicates that subsequent fields are valid. */
#define V4L2_PIX_FMT_PRIV_MAGIC 0xfeedcafe
base-commit: 36ce7124a1502bf8321668c73182372985859590
--
2.39.2
next prev parent reply other threads:[~2024-04-26 8:05 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-04-25 21:26 [PATCH v2 00/14] Generic line based metadata, without sensor API changes Sakari Ailus
2024-04-25 21:26 ` [PATCH v2 01/14] media: v4l2-subdev: Clearly document that the crop API won't be extended Sakari Ailus
2024-04-25 21:26 ` [PATCH v2 02/14] media: Documentation: Add "stream" into glossary Sakari Ailus
2024-04-25 21:27 ` [PATCH v2 03/14] media: uapi: Add generic serial metadata mbus formats Sakari Ailus
2024-04-25 21:27 ` [PATCH v2 04/14] media: uapi: Document which mbus format fields are valid for metadata Sakari Ailus
2024-04-25 21:27 ` [PATCH v2 05/14] media: uapi: v4l: Add generic 8-bit metadata format definitions Sakari Ailus
2024-04-26 8:05 ` Sakari Ailus [this message]
2024-04-25 21:27 ` [PATCH v2 06/14] media: v4l: Support line-based metadata capture Sakari Ailus
2024-04-25 21:27 ` [PATCH v2 07/14] media: v4l: Set line based metadata flag in V4L2 core Sakari Ailus
2024-04-25 21:27 ` [PATCH v2 08/14] media: Documentation: Additional streams generally don't harm capture Sakari Ailus
2024-04-25 21:27 ` [PATCH v2 09/14] media: Documentation: Document S_ROUTING behaviour Sakari Ailus
2024-04-25 21:27 ` [PATCH v2 10/14] media: v4l: subdev: Add a function to lock two sub-device states, use it Sakari Ailus
2024-04-25 21:27 ` [PATCH v2 11/14] media: v4l: subdev: Copy argument back to user also for S_ROUTING Sakari Ailus
2024-04-25 21:27 ` [PATCH v2 12/14] media: v4l: subdev: Add len_routes field to struct v4l2_subdev_routing Sakari Ailus
2024-04-25 21:27 ` [PATCH v2 13/14] media: v4l: subdev: Return routes set using S_ROUTING Sakari Ailus
2024-04-25 21:27 ` [PATCH v2 14/14] media: v4l: subdev: Add trivial set_routing support Sakari Ailus
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