media: uapi: v4l: Add generic 8-bit metadata format definitions

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>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>

3 files changed, 344 insertions, 1 deletions

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..78ab56b21682
--- /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 :term:`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 :term:`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 :term:`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