From: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
To: linux-media@vger.kernel.org, sakari.ailus@linux.intel.com,
Jacopo Mondi <jacopo+renesas@jmondi.org>,
Laurent Pinchart <laurent.pinchart@ideasonboard.com>,
niklas.soderlund+renesas@ragnatech.se,
Mauro Carvalho Chehab <mchehab@kernel.org>,
Hans Verkuil <hverkuil-cisco@xs4all.nl>,
Pratyush Yadav <p.yadav@ti.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Subject: [PATCH v11 21/36] media: Documentation: Add GS_ROUTING documentation
Date: Tue, 1 Mar 2022 18:11:41 +0200 [thread overview]
Message-ID: <20220301161156.1119557-22-tomi.valkeinen@ideasonboard.com> (raw)
In-Reply-To: <20220301161156.1119557-1-tomi.valkeinen@ideasonboard.com>
From: Jacopo Mondi <jacopo+renesas@jmondi.org>
Add documentation for VIDIOC_SUBDEV_G/S_ROUTING ioctl and add
description of multiplexed media pads and internal routing to the
V4L2-subdev documentation section.
Signed-off-by: Jacopo Mondi <jacopo+renesas@jmondi.org>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com>
Reviewed-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
---
.../userspace-api/media/v4l/dev-subdev.rst | 2 +
.../userspace-api/media/v4l/user-func.rst | 1 +
.../media/v4l/vidioc-subdev-g-routing.rst | 150 ++++++++++++++++++
3 files changed, 153 insertions(+)
create mode 100644 Documentation/userspace-api/media/v4l/vidioc-subdev-g-routing.rst
diff --git a/Documentation/userspace-api/media/v4l/dev-subdev.rst b/Documentation/userspace-api/media/v4l/dev-subdev.rst
index fd1de0a73a9f..a67c2749089a 100644
--- a/Documentation/userspace-api/media/v4l/dev-subdev.rst
+++ b/Documentation/userspace-api/media/v4l/dev-subdev.rst
@@ -29,6 +29,8 @@ will feature a character device node on which ioctls can be called to
- negotiate image formats on individual pads
+- inspect and modify internal data routing between pads of the same entity
+
Sub-device character device nodes, conventionally named
``/dev/v4l-subdev*``, use major number 81.
diff --git a/Documentation/userspace-api/media/v4l/user-func.rst b/Documentation/userspace-api/media/v4l/user-func.rst
index 53e604bd7d60..228c1521f190 100644
--- a/Documentation/userspace-api/media/v4l/user-func.rst
+++ b/Documentation/userspace-api/media/v4l/user-func.rst
@@ -70,6 +70,7 @@ Function Reference
vidioc-subdev-g-crop
vidioc-subdev-g-fmt
vidioc-subdev-g-frame-interval
+ vidioc-subdev-g-routing
vidioc-subdev-g-selection
vidioc-subdev-querycap
vidioc-subscribe-event
diff --git a/Documentation/userspace-api/media/v4l/vidioc-subdev-g-routing.rst b/Documentation/userspace-api/media/v4l/vidioc-subdev-g-routing.rst
new file mode 100644
index 000000000000..a0d9c79e162f
--- /dev/null
+++ b/Documentation/userspace-api/media/v4l/vidioc-subdev-g-routing.rst
@@ -0,0 +1,150 @@
+.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
+.. c:namespace:: V4L
+
+.. _VIDIOC_SUBDEV_G_ROUTING:
+
+******************************************************
+ioctl VIDIOC_SUBDEV_G_ROUTING, VIDIOC_SUBDEV_S_ROUTING
+******************************************************
+
+Name
+====
+
+VIDIOC_SUBDEV_G_ROUTING - VIDIOC_SUBDEV_S_ROUTING - Get or set routing between streams of media pads in a media entity.
+
+
+Synopsis
+========
+
+.. c:function:: int ioctl( int fd, VIDIOC_SUBDEV_G_ROUTING, struct v4l2_subdev_routing *argp )
+ :name: VIDIOC_SUBDEV_G_ROUTING
+
+.. c:function:: int ioctl( int fd, VIDIOC_SUBDEV_S_ROUTING, struct v4l2_subdev_routing *argp )
+ :name: VIDIOC_SUBDEV_S_ROUTING
+
+
+Arguments
+=========
+
+``fd``
+ File descriptor returned by :ref:`open() <func-open>`.
+
+``argp``
+ Pointer to struct :c:type:`v4l2_subdev_routing`.
+
+
+Description
+===========
+
+These ioctls are used to get and set the routing in a media entity.
+The routing configuration determines the flows of data inside an entity.
+
+Drivers report their current routing tables using the
+``VIDIOC_SUBDEV_G_ROUTING`` ioctl and application may enable or disable routes
+with the ``VIDIOC_SUBDEV_S_ROUTING`` ioctl, by adding or removing routes and
+setting or clearing flags of the ``flags`` field of a
+struct :c:type:`v4l2_subdev_route`.
+
+All stream configurations are reset when ``VIDIOC_SUBDEV_S_ROUTING`` is called. This
+means that the userspace mut reconfigure all streams after calling the ioctl
+with e.g. ``VIDIOC_SUBDEV_S_FMT``.
+
+A special case for routing are routes marked with
+``V4L2_SUBDEV_ROUTE_FL_SOURCE`` flag. These routes are used to describe
+source endpoints on sensors and the sink fields are unused.
+
+When inspecting routes through ``VIDIOC_SUBDEV_G_ROUTING`` and the application
+provided ``num_routes`` is not big enough to contain all the available routes
+the subdevice exposes, drivers return the ENOSPC error code and adjust the
+value of the ``num_routes`` field. Application should then reserve enough memory
+for all the route entries and call ``VIDIOC_SUBDEV_G_ROUTING`` again.
+
+.. tabularcolumns:: |p{4.4cm}|p{4.4cm}|p{8.7cm}|
+
+.. c:type:: v4l2_subdev_routing
+
+.. flat-table:: struct v4l2_subdev_routing
+ :header-rows: 0
+ :stub-columns: 0
+ :widths: 1 1 2
+
+ * - __u32
+ - ``which``
+ - Format to modified, from enum
+ :ref:`v4l2_subdev_format_whence <v4l2-subdev-format-whence>`.
+ * - struct :c:type:`v4l2_subdev_route`
+ - ``routes[]``
+ - Array of struct :c:type:`v4l2_subdev_route` entries
+ * - __u32
+ - ``num_routes``
+ - Number of entries of the routes array
+ * - __u32
+ - ``reserved``\ [5]
+ - Reserved for future extensions. Applications and drivers must set
+ the array to zero.
+
+.. tabularcolumns:: |p{4.4cm}|p{4.4cm}|p{8.7cm}|
+
+.. c:type:: v4l2_subdev_route
+
+.. flat-table:: struct v4l2_subdev_route
+ :header-rows: 0
+ :stub-columns: 0
+ :widths: 1 1 2
+
+ * - __u32
+ - ``sink_pad``
+ - Sink pad number.
+ * - __u32
+ - ``sink_stream``
+ - Sink pad stream number.
+ * - __u32
+ - ``source_pad``
+ - Source pad number.
+ * - __u32
+ - ``source_stream``
+ - Source pad stream number.
+ * - __u32
+ - ``flags``
+ - Route enable/disable flags
+ :ref:`v4l2_subdev_routing_flags <v4l2-subdev-routing-flags>`.
+ * - __u32
+ - ``reserved``\ [5]
+ - Reserved for future extensions. Applications and drivers must set
+ the array to zero.
+
+.. tabularcolumns:: |p{6.6cm}|p{2.2cm}|p{8.7cm}|
+
+.. _v4l2-subdev-routing-flags:
+
+.. flat-table:: enum v4l2_subdev_routing_flags
+ :header-rows: 0
+ :stub-columns: 0
+ :widths: 3 1 4
+
+ * - V4L2_SUBDEV_ROUTE_FL_ACTIVE
+ - 0
+ - The route is enabled. Set by applications.
+ * - V4L2_SUBDEV_ROUTE_FL_IMMUTABLE
+ - 1
+ - The route is immutable. Set by the driver.
+ * - V4L2_SUBDEV_ROUTE_FL_SOURCE
+ - 2
+ - The route is a source route, and the ``sink_pad`` and ``sink_stream``
+ fields are unused. Set by the driver.
+
+Return Value
+============
+
+On success 0 is returned, on error -1 and the ``errno`` variable is set
+appropriately. The generic error codes are described at the
+:ref:`Generic Error Codes <gen-errors>` chapter.
+
+ENOSPC
+ The number of provided route entries is less than the available ones.
+
+EINVAL
+ The sink or source pad identifiers reference a non-existing pad, or reference
+ pads of different types (ie. the sink_pad identifiers refers to a source pad)
+ or the sink or source stream identifiers reference a non-existing stream on
+ the sink or source pad.
--
2.25.1
next prev parent reply other threads:[~2022-03-01 16:12 UTC|newest]
Thread overview: 67+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-03-01 16:11 [PATCH v11 00/36] v4l: routing and streams support Tomi Valkeinen
2022-03-01 16:11 ` [PATCH v11 01/36] media: entity: Use pad as a starting point for graph walk Tomi Valkeinen
2022-03-01 16:11 ` [PATCH v11 02/36] media: entity: Use pads instead of entities in the media graph walk stack Tomi Valkeinen
2022-03-01 16:11 ` [PATCH v11 03/36] media: entity: Walk the graph based on pads Tomi Valkeinen
2022-03-01 16:11 ` [PATCH v11 04/36] media: mc: Start walk from a specific pad in use count calculation Tomi Valkeinen
2022-03-01 16:11 ` [PATCH v11 05/36] media: entity: Add iterator helper for entity pads Tomi Valkeinen
2022-03-01 16:11 ` [PATCH v11 06/36] media: entity: Move the pipeline from entity to pads Tomi Valkeinen
2022-03-01 16:11 ` [PATCH v11 07/36] media: entity: Use pad as the starting point for a pipeline Tomi Valkeinen
2022-03-01 16:11 ` [PATCH v11 08/36] media: entity: Add has_route entity operation Tomi Valkeinen
2022-03-01 16:11 ` [PATCH v11 09/36] media: entity: Add media_entity_has_route() function Tomi Valkeinen
2022-03-01 16:11 ` [PATCH v11 10/36] media: entity: Use routing information during graph traversal Tomi Valkeinen
2022-03-01 16:11 ` [PATCH v11 11/36] media: entity: Skip link validation for pads to which there is no route Tomi Valkeinen
2022-03-01 16:11 ` [PATCH v11 12/36] media: entity: Add an iterator helper for connected pads Tomi Valkeinen
2022-03-01 16:11 ` [PATCH v11 13/36] media: entity: Add only connected pads to the pipeline Tomi Valkeinen
2022-03-01 16:11 ` [PATCH v11 14/36] media: entity: Add debug information in graph walk route check Tomi Valkeinen
2022-03-01 16:11 ` [PATCH v11 15/36] media: Add bus type to frame descriptors Tomi Valkeinen
2022-03-01 16:11 ` [PATCH v11 16/36] media: Add CSI-2 bus configuration " Tomi Valkeinen
2022-03-01 16:11 ` [PATCH v11 17/36] media: Add stream to frame descriptor Tomi Valkeinen
2022-03-01 16:11 ` [PATCH v11 18/36] media: subdev: increase V4L2_FRAME_DESC_ENTRY_MAX to 8 Tomi Valkeinen
2022-03-01 16:11 ` [PATCH v11 19/36] media: add V4L2_SUBDEV_FL_MULTIPLEXED Tomi Valkeinen
2022-03-01 16:11 ` [PATCH v11 20/36] media: add V4L2_SUBDEV_CAP_MPLEXED Tomi Valkeinen
2022-03-01 16:11 ` Tomi Valkeinen [this message]
2022-03-01 16:11 ` [PATCH v11 22/36] media: subdev: Add [GS]_ROUTING subdev ioctls and operations Tomi Valkeinen
2022-07-07 9:15 ` Tomasz Figa
2022-07-14 6:47 ` Tomi Valkeinen
2022-03-01 16:11 ` [PATCH v11 23/36] media: subdev: add v4l2_subdev_has_route() Tomi Valkeinen
2022-03-01 16:11 ` [PATCH v11 24/36] media: subdev: add v4l2_subdev_set_routing helper() Tomi Valkeinen
2022-03-01 16:11 ` [PATCH v11 25/36] media: Documentation: add multiplexed streams documentation Tomi Valkeinen
2022-03-16 9:04 ` Jacopo Mondi
2022-03-17 7:18 ` Tomi Valkeinen
2022-03-17 8:27 ` Jacopo Mondi
2022-03-01 16:11 ` [PATCH v11 26/36] media: subdev: add stream based configuration Tomi Valkeinen
2022-03-16 9:59 ` Jacopo Mondi
2022-03-17 8:01 ` Tomi Valkeinen
2022-03-17 8:38 ` Jacopo Mondi
2022-03-17 8:48 ` Tomi Valkeinen
2022-03-01 16:11 ` [PATCH v11 27/36] media: subdev: use streams in v4l2_subdev_link_validate() Tomi Valkeinen
2022-03-16 10:47 ` Jacopo Mondi
2022-03-17 8:39 ` Tomi Valkeinen
2022-03-01 16:11 ` [PATCH v11 28/36] media: subdev: add "opposite" stream helper funcs Tomi Valkeinen
2022-03-16 10:50 ` Jacopo Mondi
2022-03-17 9:10 ` Tomi Valkeinen
2022-03-01 16:11 ` [PATCH v11 29/36] media: subdev: add v4l2_subdev_get_fmt() helper function Tomi Valkeinen
2022-03-16 11:00 ` Jacopo Mondi
2022-03-01 16:11 ` [PATCH v11 30/36] media: subdev: Fallback to pad config in v4l2_subdev_get_fmt() Tomi Valkeinen
2022-03-16 11:03 ` Jacopo Mondi
2022-03-17 9:18 ` Tomi Valkeinen
2022-03-01 16:11 ` [PATCH v11 31/36] media: subdev: add v4l2_subdev_set_routing_with_fmt() helper Tomi Valkeinen
2022-03-16 11:04 ` Jacopo Mondi
2022-03-01 16:11 ` [PATCH v11 32/36] media: subdev: add v4l2_subdev_routing_validate() helper Tomi Valkeinen
2022-03-16 11:10 ` Jacopo Mondi
2022-03-17 9:15 ` Tomi Valkeinen
2022-03-01 16:11 ` [PATCH v11 33/36] media: subdev: Add for_each_active_route() macro Tomi Valkeinen
2022-03-01 16:11 ` [PATCH v11 34/36] media: v4l2-subdev: Add v4l2_subdev_state_xlate_streams() helper Tomi Valkeinen
2022-03-16 11:26 ` Jacopo Mondi
2022-03-17 9:27 ` Tomi Valkeinen
2022-03-17 9:35 ` Tomi Valkeinen
2022-07-07 10:27 ` Tomasz Figa
2022-07-14 7:41 ` Tomi Valkeinen
2022-07-19 5:38 ` Tomasz Figa
2022-03-01 16:11 ` [PATCH v11 35/36] media: v4l2-subdev: Add subdev .(enable|disable)_streams() operations Tomi Valkeinen
2022-03-16 12:05 ` Jacopo Mondi
2022-03-17 9:43 ` Tomi Valkeinen
2022-03-01 16:11 ` [PATCH v11 36/36] media: v4l2-subdev: Add v4l2_subdev_s_stream_helper() function Tomi Valkeinen
2022-03-16 12:10 ` Jacopo Mondi
2022-03-17 9:45 ` Tomi Valkeinen
2022-07-07 10:38 ` [PATCH v11 00/36] v4l: routing and streams support Tomasz Figa
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