diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2016-01-13 20:46:37 +0100 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-01-13 20:46:37 +0100 |
commit | 77a76b04d2be1c45b8fd746b7ef754525029340c (patch) | |
tree | ef5db67c07d538a43d160847acefe80f3c049dba /Documentation | |
parent | Merge tag 'spi-v4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie... (diff) | |
parent | [media] Postpone the addition of MEDIA_IOC_G_TOPOLOGY (diff) | |
download | linux-77a76b04d2be1c45b8fd746b7ef754525029340c.tar.xz linux-77a76b04d2be1c45b8fd746b7ef754525029340c.zip |
Merge tag 'media/v4.5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media
Pull second batch of media updates from Mauro Carvalho Chehab:
"This is the second part of the media patches. It contains the media
controller next generation patches, with is the result of one year of
discussions and development. It also contains patches to enable media
controller support at the DVB subsystem.
The goal is to improve the media controller to allow proper support
for other types of Video4Linux devices (radio and TV ones) and to
extend the media controller functionality to allow it to be used by
other subsystems like DVB, ALSA and IIO.
In order to use the new functionality, a new ioctl is needed
(MEDIA_IOC_G_TOPOLOGY). As we're still discussing how to pack the
struct fields of this ioctl in order to avoid compat32 issues, I
decided to add a patch at the end of this series commenting out the
new ioctl, in order to postpone the addition of the new ioctl to the
next Kernel version (4.6).
With that, no userspace visible changes should happen at the media
controller API, as the existing ioctls are untouched. Yet, it helps
DVB, ALSA and IIO developers to develop and test the patches adding
media controller support there, as the core will contain all required
internal changes to allow adding support for devices that belong to
those subsystems"
* tag 'media/v4.5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (177 commits)
[media] Postpone the addition of MEDIA_IOC_G_TOPOLOGY
[media] mxl111sf: Add a tuner entity
[media] dvbdev: create links on devices with multiple frontends
[media] media-entitiy: add a function to create multiple links
[media] dvb-usb-v2: postpone removal of media_device
[media] dvbdev: Add RF connector if needed
[media] dvbdev: remove two dead functions if !CONFIG_MEDIA_CONTROLLER_DVB
[media] call media_device_init() before registering the V4L2 device
[media] uapi/media.h: Use u32 for the number of graph objects
[media] media-entity: don't sleep at media_device_register_entity()
[media] media-entity: increase max number of PADs
[media] media-entity.h: document the remaining functions
[media] media-device.h: use just one u32 counter for object ID
[media] media-entity.h fix documentation for several parameters
[media] DocBook: document media_entity_graph_walk_cleanup()
[media] move documentation to the header files
[media] media: Move MEDIA_ENTITY_MAX_PADS from media-entity.h to media-entity.c
[media] media: Remove pre-allocated entity enumeration bitmap
[media] staging: v4l: davinci_vpbe: Use the new media graph walk interface
[media] staging: v4l: omap4iss: Use the new media graph walk interface
...
Diffstat (limited to 'Documentation')
-rw-r--r-- | Documentation/DocBook/device-drivers.tmpl | 1 | ||||
-rw-r--r-- | Documentation/DocBook/media/v4l/media-controller.xml | 44 | ||||
-rw-r--r-- | Documentation/DocBook/media/v4l/media-ioc-enum-entities.xml | 104 | ||||
-rw-r--r-- | Documentation/DocBook/media/v4l/media-ioc-enum-links.xml | 56 | ||||
-rw-r--r-- | Documentation/DocBook/media/v4l/media-ioc-g-topology.xml | 394 | ||||
-rw-r--r-- | Documentation/DocBook/media/v4l/media-types.xml | 240 | ||||
-rw-r--r-- | Documentation/media-framework.txt | 372 | ||||
-rw-r--r-- | Documentation/video4linux/v4l2-framework.txt | 12 | ||||
-rw-r--r-- | Documentation/zh_CN/video4linux/v4l2-framework.txt | 8 |
9 files changed, 677 insertions, 554 deletions
diff --git a/Documentation/DocBook/device-drivers.tmpl b/Documentation/DocBook/device-drivers.tmpl index 7b3fcc5effcd..cdd8b24db68d 100644 --- a/Documentation/DocBook/device-drivers.tmpl +++ b/Documentation/DocBook/device-drivers.tmpl @@ -263,6 +263,7 @@ X!Isound/sound_firmware.c !Iinclude/media/lirc_dev.h </sect1> <sect1><title>Media Controller devices</title> +!Pinclude/media/media-device.h Media Controller !Iinclude/media/media-device.h !Iinclude/media/media-devnode.h !Iinclude/media/media-entity.h diff --git a/Documentation/DocBook/media/v4l/media-controller.xml b/Documentation/DocBook/media/v4l/media-controller.xml index 873ac3a621f0..5f2fc07a93d7 100644 --- a/Documentation/DocBook/media/v4l/media-controller.xml +++ b/Documentation/DocBook/media/v4l/media-controller.xml @@ -58,21 +58,36 @@ <title>Media device model</title> <para>Discovering a device internal topology, and configuring it at runtime, is one of the goals of the media controller API. To achieve this, hardware - devices are modelled as an oriented graph of building blocks called entities - connected through pads.</para> - <para>An entity is a basic media hardware or software building block. It can - correspond to a large variety of logical blocks such as physical hardware - devices (CMOS sensor for instance), logical hardware devices (a building - block in a System-on-Chip image processing pipeline), DMA channels or - physical connectors.</para> - <para>A pad is a connection endpoint through which an entity can interact - with other entities. Data (not restricted to video) produced by an entity - flows from the entity's output to one or more entity inputs. Pads should not - be confused with physical pins at chip boundaries.</para> - <para>A link is a point-to-point oriented connection between two pads, - either on the same entity or on different entities. Data flows from a source - pad to a sink pad.</para> + devices and Linux Kernel interfaces are modelled as graph objects on + an oriented graph. The object types that constitute the graph are:</para> + <itemizedlist> + <listitem><para>An <emphasis role="bold">entity</emphasis> + is a basic media hardware or software building block. It can correspond to + a large variety of logical blocks such as physical hardware devices + (CMOS sensor for instance), logical hardware devices (a building block in + a System-on-Chip image processing pipeline), DMA channels or physical + connectors.</para></listitem> + <listitem><para>An <emphasis role="bold">interface</emphasis> + is a graph representation of a Linux Kernel userspace API interface, + like a device node or a sysfs file that controls one or more entities + in the graph.</para></listitem> + <listitem><para>A <emphasis role="bold">pad</emphasis> + is a data connection endpoint through which an entity can interact with + other entities. Data (not restricted to video) produced by an entity + flows from the entity's output to one or more entity inputs. Pads should + not be confused with physical pins at chip boundaries.</para></listitem> + <listitem><para>A <emphasis role="bold">data link</emphasis> + is a point-to-point oriented connection between two pads, either on the + same entity or on different entities. Data flows from a source pad to a + sink pad.</para></listitem> + <listitem><para>An <emphasis role="bold">interface link</emphasis> + is a point-to-point bidirectional control connection between a Linux + Kernel interface and an entity.m</para></listitem> + </itemizedlist> </section> + + <!-- All non-ioctl specific data types go here. --> + &sub-media-types; </chapter> <appendix id="media-user-func"> @@ -83,6 +98,7 @@ &sub-media-func-ioctl; <!-- All ioctls go here. --> &sub-media-ioc-device-info; + &sub-media-ioc-g-topology; &sub-media-ioc-enum-entities; &sub-media-ioc-enum-links; &sub-media-ioc-setup-link; diff --git a/Documentation/DocBook/media/v4l/media-ioc-enum-entities.xml b/Documentation/DocBook/media/v4l/media-ioc-enum-entities.xml index 5872f8bbf774..0c4f96bfc2de 100644 --- a/Documentation/DocBook/media/v4l/media-ioc-enum-entities.xml +++ b/Documentation/DocBook/media/v4l/media-ioc-enum-entities.xml @@ -59,15 +59,6 @@ <para>Entity IDs can be non-contiguous. Applications must <emphasis>not</emphasis> try to enumerate entities by calling MEDIA_IOC_ENUM_ENTITIES with increasing id's until they get an error.</para> - <para>Two or more entities that share a common non-zero - <structfield>group_id</structfield> value are considered as logically - grouped. Groups are used to report - <itemizedlist> - <listitem><para>ALSA, VBI and video nodes that carry the same media - stream</para></listitem> - <listitem><para>lens and flash controllers associated with a sensor</para></listitem> - </itemizedlist> - </para> <table pgwide="1" frame="none" id="media-entity-desc"> <title>struct <structname>media_entity_desc</structname></title> @@ -106,7 +97,7 @@ <entry><structfield>revision</structfield></entry> <entry></entry> <entry></entry> - <entry>Entity revision in a driver/hardware specific format.</entry> + <entry>Entity revision. Always zero (obsolete)</entry> </row> <row> <entry>__u32</entry> @@ -120,7 +111,7 @@ <entry><structfield>group_id</structfield></entry> <entry></entry> <entry></entry> - <entry>Entity group ID</entry> + <entry>Entity group ID. Always zero (obsolete)</entry> </row> <row> <entry>__u16</entry> @@ -171,97 +162,6 @@ </tbody> </tgroup> </table> - - <table frame="none" pgwide="1" id="media-entity-type"> - <title>Media entity types</title> - <tgroup cols="2"> - <colspec colname="c1"/> - <colspec colname="c2"/> - <tbody valign="top"> - <row> - <entry><constant>MEDIA_ENT_T_DEVNODE</constant></entry> - <entry>Unknown device node</entry> - </row> - <row> - <entry><constant>MEDIA_ENT_T_DEVNODE_V4L</constant></entry> - <entry>V4L video, radio or vbi device node</entry> - </row> - <row> - <entry><constant>MEDIA_ENT_T_DEVNODE_FB</constant></entry> - <entry>Frame buffer device node</entry> - </row> - <row> - <entry><constant>MEDIA_ENT_T_DEVNODE_ALSA</constant></entry> - <entry>ALSA card</entry> - </row> - <row> - <entry><constant>MEDIA_ENT_T_DEVNODE_DVB_FE</constant></entry> - <entry>DVB frontend devnode</entry> - </row> - <row> - <entry><constant>MEDIA_ENT_T_DEVNODE_DVB_DEMUX</constant></entry> - <entry>DVB demux devnode</entry> - </row> - <row> - <entry><constant>MEDIA_ENT_T_DEVNODE_DVB_DVR</constant></entry> - <entry>DVB DVR devnode</entry> - </row> - <row> - <entry><constant>MEDIA_ENT_T_DEVNODE_DVB_CA</constant></entry> - <entry>DVB CAM devnode</entry> - </row> - <row> - <entry><constant>MEDIA_ENT_T_DEVNODE_DVB_NET</constant></entry> - <entry>DVB network devnode</entry> - </row> - <row> - <entry><constant>MEDIA_ENT_T_V4L2_SUBDEV</constant></entry> - <entry>Unknown V4L sub-device</entry> - </row> - <row> - <entry><constant>MEDIA_ENT_T_V4L2_SUBDEV_SENSOR</constant></entry> - <entry>Video sensor</entry> - </row> - <row> - <entry><constant>MEDIA_ENT_T_V4L2_SUBDEV_FLASH</constant></entry> - <entry>Flash controller</entry> - </row> - <row> - <entry><constant>MEDIA_ENT_T_V4L2_SUBDEV_LENS</constant></entry> - <entry>Lens controller</entry> - </row> - <row> - <entry><constant>MEDIA_ENT_T_V4L2_SUBDEV_DECODER</constant></entry> - <entry>Video decoder, the basic function of the video decoder is to - accept analogue video from a wide variety of sources such as - broadcast, DVD players, cameras and video cassette recorders, in - either NTSC, PAL or HD format and still occasionally SECAM, separate - it into its component parts, luminance and chrominance, and output - it in some digital video standard, with appropriate embedded timing - signals.</entry> - </row> - <row> - <entry><constant>MEDIA_ENT_T_V4L2_SUBDEV_TUNER</constant></entry> - <entry>TV and/or radio tuner</entry> - </row> - </tbody> - </tgroup> - </table> - - <table frame="none" pgwide="1" id="media-entity-flag"> - <title>Media entity flags</title> - <tgroup cols="2"> - <colspec colname="c1"/> - <colspec colname="c2"/> - <tbody valign="top"> - <row> - <entry><constant>MEDIA_ENT_FL_DEFAULT</constant></entry> - <entry>Default entity for its type. Used to discover the default - audio, VBI and video devices, the default camera sensor, ...</entry> - </row> - </tbody> - </tgroup> - </table> </refsect1> <refsect1> diff --git a/Documentation/DocBook/media/v4l/media-ioc-enum-links.xml b/Documentation/DocBook/media/v4l/media-ioc-enum-links.xml index 74fb394ec667..2bbeea9f3e18 100644 --- a/Documentation/DocBook/media/v4l/media-ioc-enum-links.xml +++ b/Documentation/DocBook/media/v4l/media-ioc-enum-links.xml @@ -118,35 +118,6 @@ </tgroup> </table> - <table frame="none" pgwide="1" id="media-pad-flag"> - <title>Media pad flags</title> - <tgroup cols="2"> - <colspec colname="c1"/> - <colspec colname="c2"/> - <tbody valign="top"> - <row> - <entry><constant>MEDIA_PAD_FL_SINK</constant></entry> - <entry>Input pad, relative to the entity. Input pads sink data and - are targets of links.</entry> - </row> - <row> - <entry><constant>MEDIA_PAD_FL_SOURCE</constant></entry> - <entry>Output pad, relative to the entity. Output pads source data - and are origins of links.</entry> - </row> - <row> - <entry><constant>MEDIA_PAD_FL_MUST_CONNECT</constant></entry> - <entry>If this flag is set and the pad is linked to any other - pad, then at least one of those links must be enabled for the - entity to be able to stream. There could be temporary reasons - (e.g. device configuration dependent) for the pad to need - enabled links even when this flag isn't set; the absence of the - flag doesn't imply there is none.</entry> - </row> - </tbody> - </tgroup> - </table> - <table pgwide="1" frame="none" id="media-link-desc"> <title>struct <structname>media_link_desc</structname></title> <tgroup cols="3"> @@ -171,33 +142,6 @@ </tgroup> </table> - <table frame="none" pgwide="1" id="media-link-flag"> - <title>Media link flags</title> - <tgroup cols="2"> - <colspec colname="c1"/> - <colspec colname="c2"/> - <tbody valign="top"> - <row> - <entry><constant>MEDIA_LNK_FL_ENABLED</constant></entry> - <entry>The link is enabled and can be used to transfer media data. - When two or more links target a sink pad, only one of them can be - enabled at a time.</entry> - </row> - <row> - <entry><constant>MEDIA_LNK_FL_IMMUTABLE</constant></entry> - <entry>The link enabled state can't be modified at runtime. An - immutable link is always enabled.</entry> - </row> - <row> - <entry><constant>MEDIA_LNK_FL_DYNAMIC</constant></entry> - <entry>The link enabled state can be modified during streaming. This - flag is set by drivers and is read-only for applications.</entry> - </row> - </tbody> - </tgroup> - </table> - <para>One and only one of <constant>MEDIA_PAD_FL_SINK</constant> and - <constant>MEDIA_PAD_FL_SOURCE</constant> must be set for every pad.</para> </refsect1> <refsect1> diff --git a/Documentation/DocBook/media/v4l/media-ioc-g-topology.xml b/Documentation/DocBook/media/v4l/media-ioc-g-topology.xml new file mode 100644 index 000000000000..63152ab9efba --- /dev/null +++ b/Documentation/DocBook/media/v4l/media-ioc-g-topology.xml @@ -0,0 +1,394 @@ +<refentry id="media-g-topology"> + <refmeta> + <refentrytitle>ioctl MEDIA_IOC_G_TOPOLOGY</refentrytitle> + &manvol; + </refmeta> + + <refnamediv> + <refname>MEDIA_IOC_G_TOPOLOGY</refname> + <refpurpose>Enumerate the graph topology and graph element properties</refpurpose> + </refnamediv> + + <refsynopsisdiv> + <funcsynopsis> + <funcprototype> + <funcdef>int <function>ioctl</function></funcdef> + <paramdef>int <parameter>fd</parameter></paramdef> + <paramdef>int <parameter>request</parameter></paramdef> + <paramdef>struct media_v2_topology *<parameter>argp</parameter></paramdef> + </funcprototype> + </funcsynopsis> + </refsynopsisdiv> + + <refsect1> + <title>Arguments</title> + + <variablelist> + <varlistentry> + <term><parameter>fd</parameter></term> + <listitem> + <para>File descriptor returned by + <link linkend='media-func-open'><function>open()</function></link>.</para> + </listitem> + </varlistentry> + <varlistentry> + <term><parameter>request</parameter></term> + <listitem> + <para>MEDIA_IOC_G_TOPOLOGY</para> + </listitem> + </varlistentry> + <varlistentry> + <term><parameter>argp</parameter></term> + <listitem> + <para></para> + </listitem> + </varlistentry> + </variablelist> + </refsect1> + + <refsect1> + <title>Description</title> + + <para><emphasis role="bold">NOTE:</emphasis> This new ioctl is programmed to be added on Kernel 4.6. Its definition/arguments may change until its final version.</para> + + <para>The typical usage of this ioctl is to call it twice. + On the first call, the structure defined at &media-v2-topology; should + be zeroed. At return, if no errors happen, this ioctl will return the + <constant>topology_version</constant> and the total number of entities, + interfaces, pads and links.</para> + <para>Before the second call, the userspace should allocate arrays to + store the graph elements that are desired, putting the pointers to them + at the ptr_entities, ptr_interfaces, ptr_links and/or ptr_pads, keeping + the other values untouched.</para> + <para>If the <constant>topology_version</constant> remains the same, the + ioctl should fill the desired arrays with the media graph elements.</para> + + <table pgwide="1" frame="none" id="media-v2-topology"> + <title>struct <structname>media_v2_topology</structname></title> + <tgroup cols="5"> + <colspec colname="c1" /> + <colspec colname="c2" /> + <colspec colname="c3" /> + <colspec colname="c4" /> + <colspec colname="c5" /> + <tbody valign="top"> + <row> + <entry>__u64</entry> + <entry><structfield>topology_version</structfield></entry> + <entry></entry> + <entry></entry> + <entry>Version of the media graph topology. When the graph is + created, this field starts with zero. Every time a graph + element is added or removed, this field is + incremented.</entry> + </row> + <row> + <entry>__u64</entry> + <entry><structfield>num_entities</structfield></entry> + <entry></entry> + <entry></entry> + <entry>Number of entities in the graph</entry> + </row> + <row> + <entry>__u64</entry> + <entry><structfield>ptr_entities</structfield></entry> + <entry></entry> + <entry></entry> + <entry>A pointer to a memory area where the entities array + will be stored, converted to a 64-bits integer. + It can be zero. if zero, the ioctl won't store the + entities. It will just update + <constant>num_entities</constant></entry> + </row> + <row> + <entry>__u64</entry> + <entry><structfield>num_interfaces</structfield></entry> + <entry></entry> + <entry></entry> + <entry>Number of interfaces in the graph</entry> + </row> + <row> + <entry>__u64</entry> + <entry><structfield>ptr_interfaces</structfield></entry> + <entry></entry> + <entry></entry> + <entry>A pointer to a memory area where the interfaces array + will be stored, converted to a 64-bits integer. + It can be zero. if zero, the ioctl won't store the + interfaces. It will just update + <constant>num_interfaces</constant></entry> + </row> + <row> + <entry>__u64</entry> + <entry><structfield>num_pads</structfield></entry> + <entry></entry> + <entry></entry> + <entry>Total number of pads in the graph</entry> + </row> + <row> + <entry>__u64</entry> + <entry><structfield>ptr_pads</structfield></entry> + <entry></entry> + <entry></entry> + <entry>A pointer to a memory area where the pads array + will be stored, converted to a 64-bits integer. + It can be zero. if zero, the ioctl won't store the + pads. It will just update + <constant>num_pads</constant></entry> + </row> + <row> + <entry>__u64</entry> + <entry><structfield>num_links</structfield></entry> + <entry></entry> + <entry></entry> + <entry>Total number of data and interface links in the graph</entry> + </row> + <row> + <entry>__u64</entry> + <entry><structfield>ptr_links</structfield></entry> + <entry></entry> + <entry></entry> + <entry>A pointer to a memory area where the links array + will be stored, converted to a 64-bits integer. + It can be zero. if zero, the ioctl won't store the + links. It will just update + <constant>num_links</constant></entry> + </row> + </tbody> + </tgroup> + </table> + + <table pgwide="1" frame="none" id="media-v2-entity"> + <title>struct <structname>media_v2_entity</structname></title> + <tgroup cols="5"> + <colspec colname="c1" /> + <colspec colname="c2" /> + <colspec colname="c3" /> + <colspec colname="c4" /> + <colspec colname="c5" /> + <tbody valign="top"> + <row> + <entry>__u32</entry> + <entry><structfield>id</structfield></entry> + <entry></entry> + <entry></entry> + <entry>Unique ID for the entity.</entry> + </row> + <row> + <entry>char</entry> + <entry><structfield>name</structfield>[64]</entry> + <entry></entry> + <entry></entry> + <entry>Entity name as an UTF-8 NULL-terminated string.</entry> + </row> + <row> + <entry>__u32</entry> + <entry><structfield>function</structfield></entry> + <entry></entry> + <entry></entry> + <entry>Entity main function, see <xref linkend="media-entity-type" /> for details.</entry> + </row> + <row> + <entry>__u32</entry> + <entry><structfield>reserved</structfield>[12]</entry> + <entry>Reserved for future extensions. Drivers and applications must + set this array to zero.</entry> + </row> + </tbody> + </tgroup> + </table> + + <table pgwide="1" frame="none" id="media-v2-interface"> + <title>struct <structname>media_v2_interface</structname></title> + <tgroup cols="5"> + <colspec colname="c1" /> + <colspec colname="c2" /> + <colspec colname="c3" /> + <colspec colname="c4" /> + <colspec colname="c5" /> + <tbody valign="top"> + <row> + <entry>__u32</entry> + <entry><structfield>id</structfield></entry> + <entry></entry> + <entry></entry> + <entry>Unique ID for the interface.</entry> + </row> + <row> + <entry>__u32</entry> + <entry><structfield>intf_type</structfield></entry> + <entry></entry> + <entry></entry> + <entry>Interface type, see <xref linkend="media-intf-type" /> for details.</entry> + </row> + <row> + <entry>__u32</entry> + <entry><structfield>flags</structfield></entry> + <entry></entry> + <entry></entry> + <entry>Interface flags. Currently unused.</entry> + </row> + <row> + <entry>__u32</entry> + <entry><structfield>reserved</structfield>[9]</entry> + <entry></entry> + <entry></entry> + <entry>Reserved for future extensions. Drivers and applications must + set this array to zero.</entry> + </row> + <row> + <entry>struct media_v2_intf_devnode</entry> + <entry><structfield>devnode</structfield></entry> + <entry></entry> + <entry></entry> + <entry>Used only for device node interfaces. See <xref linkend="media-v2-intf-devnode" /> for details..</entry> + </row> + </tbody> + </tgroup> + </table> + + <table pgwide="1" frame="none" id="media-v2-intf-devnode"> + <title>struct <structname>media_v2_interface</structname></title> + <tgroup cols="5"> + <colspec colname="c1" /> + <colspec colname="c2" /> + <colspec colname="c3" /> + <colspec colname="c4" /> + <colspec colname="c5" /> + <tbody valign="top"> + <row> + <entry>__u32</entry> + <entry><structfield>major</structfield></entry> + <entry></entry> + <entry></entry> + <entry>Device node major number.</entry> + </row> + <row> + <entry>__u32</entry> + <entry><structfield>minor</structfield></entry> + <entry></entry> + <entry></entry> + <entry>Device node minor number.</entry> + </row> + </tbody> + </tgroup> + </table> + + <table pgwide="1" frame="none" id="media-v2-pad"> + <title>struct <structname>media_v2_pad</structname></title> + <tgroup cols="5"> + <colspec colname="c1" /> + <colspec colname="c2" /> + <colspec colname="c3" /> + <colspec colname="c4" /> + <colspec colname="c5" /> + <tbody valign="top"> + <row> + <entry>__u32</entry> + <entry><structfield>id</structfield></entry> + <entry></entry> + <entry></entry> + <entry>Unique ID for the pad.</entry> + </row> + <row> + <entry>__u32</entry> + <entry><structfield>entity_id</structfield></entry> + <entry></entry> + <entry></entry> + <entry>Unique ID for the entity where this pad belongs.</entry> + </row> + <row> + <entry>__u32</entry> + <entry><structfield>flags</structfield></entry> + <entry></entry> + <entry></entry> + <entry>Pad flags, see <xref linkend="media-pad-flag" /> for more details.</entry> + </row> + <row> + <entry>__u32</entry> + <entry><structfield>reserved</structfield>[9]</entry> + <entry></entry> + <entry></entry> + <entry>Reserved for future extensions. Drivers and applications must + set this array to zero.</entry> + </row> + </tbody> + </tgroup> + </table> + + <table pgwide="1" frame="none" id="media-v2-link"> + <title>struct <structname>media_v2_pad</structname></title> + <tgroup cols="5"> + <colspec colname="c1" /> + <colspec colname="c2" /> + <colspec colname="c3" /> + <colspec colname="c4" /> + <colspec colname="c5" /> + <tbody valign="top"> + <row> + <entry>__u32</entry> + <entry><structfield>id</structfield></entry> + <entry></entry> + <entry></entry> + <entry>Unique ID for the pad.</entry> + </row> + <row> + <entry>__u32</entry> + <entry><structfield>source_id</structfield></entry> + <entry></entry> + <entry></entry> + <entry> + <para>On pad to pad links: unique ID for the source pad.</para> + <para>On interface to entity links: unique ID for the interface.</para> + </entry> + </row> + <row> + <entry>__u32</entry> + <entry><structfield>sink_id</structfield></entry> + <entry></entry> + <entry></entry> + <entry> + <para>On pad to pad links: unique ID for the sink pad.</para> + <para>On interface to entity links: unique ID for the entity.</para> + </entry> + </row> + <row> + <entry>__u32</entry> + <entry><structfield>flags</structfield></entry> + <entry></entry> + <entry></entry> + <entry>Link flags, see <xref linkend="media-link-flag" /> for more details.</entry> + </row> + <row> + <entry>__u32</entry> + <entry><structfield>reserved</structfield>[5]</entry> + <entry></entry> + <entry></entry> + <entry>Reserved for future extensions. Drivers and applications must + set this array to zero.</entry> + </row> + </tbody> + </tgroup> + </table> + + </refsect1> + + <refsect1> + &return-value; + + <variablelist> + <varlistentry> + <term><errorcode>ENOSPC</errorcode></term> + <listitem> + <para>This is returned when either one or more of the num_entities, + num_interfaces, num_links or num_pads are non-zero and are smaller + than the actual number of elements inside the graph. This may happen + if the <constant>topology_version</constant> changed when compared + to the last time this ioctl was called. Userspace should usually + free the area for the pointers, zero the struct elements and call + this ioctl again.</para> + </listitem> + </varlistentry> + </variablelist> + </refsect1> +</refentry> diff --git a/Documentation/DocBook/media/v4l/media-types.xml b/Documentation/DocBook/media/v4l/media-types.xml new file mode 100644 index 000000000000..1af384250910 --- /dev/null +++ b/Documentation/DocBook/media/v4l/media-types.xml @@ -0,0 +1,240 @@ +<section id="media-controller-types"> +<title>Types and flags used to represent the media graph elements</title> + + <table frame="none" pgwide="1" id="media-entity-type"> + <title>Media entity types</title> + <tgroup cols="2"> + <colspec colname="c1"/> + <colspec colname="c2"/> + <tbody valign="top"> + <row> + <entry><constant>MEDIA_ENT_F_UNKNOWN</constant> and <constant>MEDIA_ENT_F_V4L2_SUBDEV_UNKNOWN</constant></entry> + <entry>Unknown entity. That generally indicates that + a driver didn't initialize properly the entity, with is a Kernel bug</entry> + </row> + <row> + <entry><constant>MEDIA_ENT_F_IO_V4L</constant></entry> + <entry>Data streaming input and/or output entity.</entry> + </row> + <row> + <entry><constant>MEDIA_ENT_F_IO_VBI</constant></entry> + <entry>V4L VBI streaming input or output entity</entry> + </row> + <row> + <entry><constant>MEDIA_ENT_F_IO_SWRADIO</constant></entry> + <entry>V4L Software Digital Radio (SDR) streaming input or output entity</entry> + </row> + <row> + <entry><constant>MEDIA_ENT_F_IO_DTV</constant></entry> + <entry>DVB Digital TV streaming input or output entity</entry> + </row> + <row> + <entry><constant>MEDIA_ENT_F_DTV_DEMOD</constant></entry> + <entry>Digital TV demodulator entity.</entry> + </row> + <row> + <entry><constant>MEDIA_ENT_F_TS_DEMUX</constant></entry> + <entry>MPEG Transport stream demux entity. Could be implemented on hardware or in Kernelspace by the Linux DVB subsystem.</entry> + </row> + <row> + <entry><constant>MEDIA_ENT_F_DTV_CA</constant></entry> + <entry>Digital TV Conditional Access module (CAM) entity</entry> + </row> + <row> + <entry><constant>MEDIA_ENT_F_DTV_NET_DECAP</constant></entry> + <entry>Digital TV network ULE/MLE desencapsulation entity. Could be implemented on hardware or in Kernelspace</entry> + </row> + <row> + <entry><constant>MEDIA_ENT_F_CONN_RF</constant></entry> + <entry>Connector for a Radio Frequency (RF) signal.</entry> + </row> + <row> + <entry><constant>MEDIA_ENT_F_CONN_SVIDEO</constant></entry> + <entry>Connector for a S-Video signal.</entry> + </row> + <row> + <entry><constant>MEDIA_ENT_F_CONN_COMPOSITE</constant></entry> + <entry>Connector for a RGB composite signal.</entry> + </row> + <row> + <entry><constant>MEDIA_ENT_F_CONN_TEST</constant></entry> + <entry>Connector for a test generator.</entry> + </row> + <row> + <entry><constant>MEDIA_ENT_F_CAM_SENSOR</constant></entry> + <entry>Camera video sensor entity.</entry> + </row> + <row> + <entry><constant>MEDIA_ENT_F_FLASH</constant></entry> + <entry>Flash controller entity.</entry> + </row> + <row> + <entry><constant>MEDIA_ENT_F_LENS</constant></entry> + <entry>Lens controller entity.</entry> + </row> + <row> + <entry><constant>MEDIA_ENT_F_ATV_DECODER</constant></entry> + <entry>Analog video decoder, the basic function of the video decoder + is to accept analogue video from a wide variety of sources such as + broadcast, DVD players, cameras and video cassette recorders, in + either NTSC, PAL, SECAM or HD format, separating the stream + into its component parts, luminance and chrominance, and output + it in some digital video standard, with appropriate timing + signals.</entry> + </row> + <row> + <entry><constant>MEDIA_ENT_F_TUNER</constant></entry> + <entry>Digital TV, analog TV, radio and/or software radio tuner.</entry> + </row> + </tbody> + </tgroup> + </table> + + <table frame="none" pgwide="1" id="media-entity-flag"> + <title>Media entity flags</title> + <tgroup cols="2"> + <colspec colname="c1"/> + <colspec colname="c2"/> + <tbody valign="top"> + <row> + <entry><constant>MEDIA_ENT_FL_DEFAULT</constant></entry> + <entry>Default entity for its type. Used to discover the default + audio, VBI and video devices, the default camera sensor, ...</entry> + </row> + <row> + <entry><constant>MEDIA_ENT_FL_CONNECTOR</constant></entry> + <entry>The entity represents a data conector</entry> + </row> + </tbody> + </tgroup> + </table> + + <table frame="none" pgwide="1" id="media-intf-type"> + <title>Media interface types</title> + <tgroup cols="3"> + <colspec colname="c1"/> + <colspec colname="c2"/> + <colspec colname="c3"/> + <tbody valign="top"> + <row> + <entry><constant>MEDIA_INTF_T_DVB_FE</constant></entry> + <entry>Device node interface for the Digital TV frontend</entry> + <entry>typically, /dev/dvb/adapter?/frontend?</entry> + </row> + <row> + <entry><constant>MEDIA_INTF_T_DVB_DEMUX</constant></entry> + <entry>Device node interface for the Digital TV demux</entry> + <entry>typically, /dev/dvb/adapter?/demux?</entry> + </row> + <row> + <entry><constant>MEDIA_INTF_T_DVB_DVR</constant></entry> + <entry>Device node interface for the Digital TV DVR</entry> + <entry>typically, /dev/dvb/adapter?/dvr?</entry> + </row> + <row> + <entry><constant>MEDIA_INTF_T_DVB_CA</constant></entry> + <entry>Device node interface for the Digital TV Conditional Access</entry> + <entry>typically, /dev/dvb/adapter?/ca?</entry> + </row> + <row> + <entry><constant>MEDIA_INTF_T_DVB_FE</constant></entry> + <entry>Device node interface for the Digital TV network control</entry> + <entry>typically, /dev/dvb/adapter?/net?</entry> + </row> + <row> + <entry><constant>MEDIA_INTF_T_V4L_VIDEO</constant></entry> + <entry>Device node interface for video (V4L)</entry> + <entry>typically, /dev/video?</entry> + </row> + <row> + <entry><constant>MEDIA_INTF_T_V4L_VBI</constant></entry> + <entry>Device node interface for VBI (V4L)</entry> + <entry>typically, /dev/vbi?</entry> + </row> + <row> + <entry><constant>MEDIA_INTF_T_V4L_RADIO</constant></entry> + <entry>Device node interface for radio (V4L)</entry> + <entry>typically, /dev/vbi?</entry> + </row> + <row> + <entry><constant>MEDIA_INTF_T_V4L_SUBDEV</constant></entry> + <entry>Device node interface for a V4L subdevice</entry> + <entry>typically, /dev/v4l-subdev?</entry> + </row> + <row> + <entry><constant>MEDIA_INTF_T_V4L_SWRADIO</constant></entry> + <entry>Device node interface for Software Defined Radio (V4L)</entry> + <entry>typically, /dev/swradio?</entry> + </row> + </tbody> + </tgroup> + </table> + + <table frame="none" pgwide="1" id="media-pad-flag"> + <title>Media pad flags</title> + <tgroup cols="2"> + <colspec colname="c1"/> + <colspec colname="c2"/> + <tbody valign="top"> + <row> + <entry><constant>MEDIA_PAD_FL_SINK</constant></entry> + <entry>Input pad, relative to the entity. Input pads sink data and + are targets of links.</entry> + </row> + <row> + <entry><constant>MEDIA_PAD_FL_SOURCE</constant></entry> + <entry>Output pad, relative to the entity. Output pads source data + and are origins of links.</entry> + </row> + <row> + <entry><constant>MEDIA_PAD_FL_MUST_CONNECT</constant></entry> + <entry>If this flag is set and the pad is linked to any other + pad, then at least one of those links must be enabled for the + entity to be able to stream. There could be temporary reasons + (e.g. device configuration dependent) for the pad to need + enabled links even when this flag isn't set; the absence of the + flag doesn't imply there is none.</entry> + </row> + </tbody> + </tgroup> + </table> + + <para>One and only one of <constant>MEDIA_PAD_FL_SINK</constant> and + <constant>MEDIA_PAD_FL_SOURCE</constant> must be set for every pad.</para> + + <table frame="none" pgwide="1" id="media-link-flag"> + <title>Media link flags</title> + <tgroup cols="2"> + <colspec colname="c1"/> + <colspec colname="c2"/> + <tbody valign="top"> + <row> + <entry><constant>MEDIA_LNK_FL_ENABLED</constant></entry> + <entry>The link is enabled and can be used to transfer media data. + When two or more links target a sink pad, only one of them can be + enabled at a time.</entry> + </row> + <row> + <entry><constant>MEDIA_LNK_FL_IMMUTABLE</constant></entry> + <entry>The link enabled state can't be modified at runtime. An + immutable link is always enabled.</entry> + </row> + <row> + <entry><constant>MEDIA_LNK_FL_DYNAMIC</constant></entry> + <entry>The link enabled state can be modified during streaming. This + flag is set by drivers and is read-only for applications.</entry> + </row> + <row> + <entry><constant>MEDIA_LNK_FL_LINK_TYPE</constant></entry> + <entry><para>This is a bitmask that defines the type of the link. + Currently, two types of links are supported:</para> + <para><constant>MEDIA_LNK_FL_DATA_LINK</constant> + if the link is between two pads</para> + <para><constant>MEDIA_LNK_FL_INTERFACE_LINK</constant> + if the link is between an interface and an entity</para></entry> + </row> + </tbody> + </tgroup> + </table> + +</section> diff --git a/Documentation/media-framework.txt b/Documentation/media-framework.txt deleted file mode 100644 index f552a75c0e70..000000000000 --- a/Documentation/media-framework.txt +++ /dev/null @@ -1,372 +0,0 @@ -Linux kernel media framework -============================ - -This document describes the Linux kernel media framework, its data structures, -functions and their usage. - - -Introduction ------------- - -The media controller API is documented in DocBook format in -Documentation/DocBook/media/v4l/media-controller.xml. This document will focus -on the kernel-side implementation of the media framework. - - -Abstract media device model ---------------------------- - -Discovering a device internal topology, and configuring it at runtime, is one -of the goals of the media framework. To achieve this, hardware devices are -modelled as an oriented graph of building blocks called entities connected -through pads. - -An entity is a basic media hardware building block. It can correspond to -a large variety of logical blocks such as physical hardware devices -(CMOS sensor for instance), logical hardware devices (a building block -in a System-on-Chip image processing pipeline), DMA channels or physical -connectors. - -A pad is a connection endpoint through which an entity can interact with -other entities. Data (not restricted to video) produced by an entity -flows from the entity's output to one or more entity inputs. Pads should -not be confused with physical pins at chip boundaries. - -A link is a point-to-point oriented connection between two pads, either -on the same entity or on different entities. Data flows from a source -pad to a sink pad. - - -Media device ------------- - -A media device is represented by a struct media_device instance, defined in -include/media/media-device.h. Allocation of the structure is handled by the -media device driver, usually by embedding the media_device instance in a -larger driver-specific structure. - -Drivers register media device instances by calling - - media_device_register(struct media_device *mdev); - -The caller is responsible for initializing the media_device structure before -registration. The following fields must be set: - - - dev must point to the parent device (usually a pci_dev, usb_interface or - platform_device instance). - - - model must be filled with the device model name as a NUL-terminated UTF-8 - string. The device/model revision must not be stored in this field. - -The following fields are optional: - - - serial is a unique serial number stored as a NUL-terminated ASCII string. - The field is big enough to store a GUID in text form. If the hardware - doesn't provide a unique serial number this field must be left empty. - - - bus_info represents the location of the device in the system as a - NUL-terminated ASCII string. For PCI/PCIe devices bus_info must be set to - "PCI:" (or "PCIe:") followed by the value of pci_name(). For USB devices, - the usb_make_path() function must be used. This field is used by - applications to distinguish between otherwise identical devices that don't - provide a serial number. - - - hw_revision is the hardware device revision in a driver-specific format. - When possible the revision should be formatted with the KERNEL_VERSION - macro. - - - driver_version is formatted with the KERNEL_VERSION macro. The version - minor must be incremented when new features are added to the userspace API - without breaking binary compatibility. The version major must be - incremented when binary compatibility is broken. - -Upon successful registration a character device named media[0-9]+ is created. -The device major and minor numbers are dynamic. The model name is exported as -a sysfs attribute. - -Drivers unregister media device instances by calling - - media_device_unregister(struct media_device *mdev); - -Unregistering a media device that hasn't been registered is *NOT* safe. - - -Entities, pads and links ------------------------- - -- Entities - -Entities are represented by a struct media_entity instance, defined in -include/media/media-entity.h. The structure is usually embedded into a -higher-level structure, such as a v4l2_subdev or video_device instance, -although drivers can allocate entities directly. - -Drivers initialize entities by calling - - media_entity_init(struct media_entity *entity, u16 num_pads, - struct media_pad *pads, u16 extra_links); - -The media_entity name, type, flags, revision and group_id fields can be -initialized before or after calling media_entity_init. Entities embedded in -higher-level standard structures can have some of those fields set by the -higher-level framework. - -As the number of pads is known in advance, the pads array is not allocated -dynamically but is managed by the entity driver. Most drivers will embed the -pads array in a driver-specific structure, avoiding dynamic allocation. - -Drivers must set the direction of every pad in the pads array before calling -media_entity_init. The function will initialize the other pads fields. - -Unlike the number of pads, the total number of links isn't always known in -advance by the entity driver. As an initial estimate, media_entity_init -pre-allocates a number of links equal to the number of pads plus an optional -number of extra links. The links array will be reallocated if it grows beyond -the initial estimate. - -Drivers register entities with a media device by calling - - media_device_register_entity(struct media_device *mdev, - struct media_entity *entity); - -Entities are identified by a unique positive integer ID. Drivers can provide an -ID by filling the media_entity id field prior to registration, or request the -media controller framework to assign an ID automatically. Drivers that provide -IDs manually must ensure that all IDs are unique. IDs are not guaranteed to be -contiguous even when they are all assigned automatically by the framework. - -Drivers unregister entities by calling - - media_device_unregister_entity(struct media_entity *entity); - -Unregistering an entity will not change the IDs of the other entities, and the -ID will never be reused for a newly registered entity. - -When a media device is unregistered, all its entities are unregistered -automatically. No manual entities unregistration is then required. - -Drivers free resources associated with an entity by calling - - media_entity_cleanup(struct media_entity *entity); - -This function must be called during the cleanup phase after unregistering the -entity. Note that the media_entity instance itself must be freed explicitly by -the driver if required. - -Entities have flags that describe the entity capabilities and state. - - MEDIA_ENT_FL_DEFAULT indicates the default entity for a given type. - This can be used to report the default audio and video devices or the - default camera sensor. - -Logical entity groups can be defined by setting the group ID of all member -entities to the same non-zero value. An entity group serves no purpose in the -kernel, but is reported to userspace during entities enumeration. The group_id -field belongs to the media device driver and must not by touched by entity -drivers. - -Media device drivers should define groups if several entities are logically -bound together. Example usages include reporting - - - ALSA, VBI and video nodes that carry the same media stream - - lens and flash controllers associated with a sensor - -- Pads - -Pads are represented by a struct media_pad instance, defined in -include/media/media-entity.h. Each entity stores its pads in a pads array -managed by the entity driver. Drivers usually embed the array in a -driver-specific structure. - -Pads are identified by their entity and their 0-based index in the pads array. -Both information are stored in the media_pad structure, making the media_pad -pointer the canonical way to store and pass link references. - -Pads have flags that describe the pad capabilities and state. - - MEDIA_PAD_FL_SINK indicates that the pad supports sinking data. - MEDIA_PAD_FL_SOURCE indicates that the pad supports sourcing data. - -One and only one of MEDIA_PAD_FL_SINK and MEDIA_PAD_FL_SOURCE must be set for -each pad. - -- Links - -Links are represented by a struct media_link instance, defined in -include/media/media-entity.h. Each entity stores all links originating at or -targeting any of its pads in a links array. A given link is thus stored -twice, once in the source entity and once in the target entity. The array is -pre-allocated and grows dynamically as needed. - -Drivers create links by calling - - media_entity_create_link(struct media_entity *source, u16 source_pad, - struct media_entity *sink, u16 sink_pad, - u32 flags); - -An entry in the link array of each entity is allocated and stores pointers -to source and sink pads. - -Links have flags that describe the link capabilities and state. - - MEDIA_LNK_FL_ENABLED indicates that the link is enabled and can be used - to transfer media data. When two or more links target a sink pad, only - one of them can be enabled at a time. - MEDIA_LNK_FL_IMMUTABLE indicates that the link enabled state can't be - modified at runtime. If MEDIA_LNK_FL_IMMUTABLE is set, then - MEDIA_LNK_FL_ENABLED must also be set since an immutable link is always - enabled. - - -Graph traversal ---------------- - -The media framework provides APIs to iterate over entities in a graph. - -To iterate over all entities belonging to a media device, drivers can use the -media_device_for_each_entity macro, defined in include/media/media-device.h. - - struct media_entity *entity; - - media_device_for_each_entity(entity, mdev) { - /* entity will point to each entity in turn */ - ... - } - -Drivers might also need to iterate over all entities in a graph that can be -reached only through enabled links starting at a given entity. The media -framework provides a depth-first graph traversal API for that purpose. - -Note that graphs with cycles (whether directed or undirected) are *NOT* -supported by the graph traversal API. To prevent infinite loops, the graph -traversal code limits the maximum depth to MEDIA_ENTITY_ENUM_MAX_DEPTH, -currently defined as 16. - -Drivers initiate a graph traversal by calling - - media_entity_graph_walk_start(struct media_entity_graph *graph, - struct media_entity *entity); - -The graph structure, provided by the caller, is initialized to start graph -traversal at the given entity. - -Drivers can then retrieve the next entity by calling - - media_entity_graph_walk_next(struct media_entity_graph *graph); - -When the graph traversal is complete the function will return NULL. - -Graph traversal can be interrupted at any moment. No cleanup function call is -required and the graph structure can be freed normally. - -Helper functions can be used to find a link between two given pads, or a pad -connected to another pad through an enabled link - - media_entity_find_link(struct media_pad *source, - struct media_pad *sink); - - media_entity_remote_pad(struct media_pad *pad); - -Refer to the kerneldoc documentation for more information. - - -Use count and power handling ----------------------------- - -Due to the wide differences between drivers regarding power management needs, -the media controller does not implement power management. However, the -media_entity structure includes a use_count field that media drivers can use to -track the number of users of every entity for power management needs. - -The use_count field is owned by media drivers and must not be touched by entity -drivers. Access to the field must be protected by the media device graph_mutex -lock. - - -Links setup ------------ - -Link properties can be modified at runtime by calling - - media_entity_setup_link(struct media_link *link, u32 flags); - -The flags argument contains the requested new link flags. - -The only configurable property is the ENABLED link flag to enable/disable a -link. Links marked with the IMMUTABLE link flag can not be enabled or disabled. - -When a link is enabled or disabled, the media framework calls the -link_setup operation for the two entities at the source and sink of the link, -in that order. If the second link_setup call fails, another link_setup call is -made on the first entity to restore the original link flags. - -Media device drivers can be notified of link setup operations by setting the -media_device::link_notify pointer to a callback function. If provided, the -notification callback will be called before enabling and after disabling -links. - -Entity drivers must implement the link_setup operation if any of their links -is non-immutable. The operation must either configure the hardware or store -the configuration information to be applied later. - -Link configuration must not have any side effect on other links. If an enabled -link at a sink pad prevents another link at the same pad from being enabled, -the link_setup operation must return -EBUSY and can't implicitly disable the -first enabled link. - - -Pipelines and media streams ---------------------------- - -When starting streaming, drivers must notify all entities in the pipeline to -prevent link states from being modified during streaming by calling - - media_entity_pipeline_start(struct media_entity *entity, - struct media_pipeline *pipe); - -The function will mark all entities connected to the given entity through -enabled links, either directly or indirectly, as streaming. - -The media_pipeline instance pointed to by the pipe argument will be stored in -every entity in the pipeline. Drivers should embed the media_pipeline structure -in higher-level pipeline structures and can then access the pipeline through -the media_entity pipe field. - -Calls to media_entity_pipeline_start() can be nested. The pipeline pointer must -be identical for all nested calls to the function. - -media_entity_pipeline_start() may return an error. In that case, it will -clean up any of the changes it did by itself. - -When stopping the stream, drivers must notify the entities with - - media_entity_pipeline_stop(struct media_entity *entity); - -If multiple calls to media_entity_pipeline_start() have been made the same -number of media_entity_pipeline_stop() calls are required to stop streaming. The -media_entity pipe field is reset to NULL on the last nested stop call. - -Link configuration will fail with -EBUSY by default if either end of the link is -a streaming entity. Links that can be modified while streaming must be marked -with the MEDIA_LNK_FL_DYNAMIC flag. - -If other operations need to be disallowed on streaming entities (such as -changing entities configuration parameters) drivers can explicitly check the -media_entity stream_count field to find out if an entity is streaming. This -operation must be done with the media_device graph_mutex held. - - -Link validation ---------------- - -Link validation is performed by media_entity_pipeline_start() for any -entity which has sink pads in the pipeline. The -media_entity::link_validate() callback is used for that purpose. In -link_validate() callback, entity driver should check that the properties of -the source pad of the connected entity and its own sink pad match. It is up -to the type of the entity (and in the end, the properties of the hardware) -what matching actually means. - -Subsystems should facilitate link validation by providing subsystem specific -helper functions to provide easy access for commonly needed information, and -in the end provide a way to use driver-specific callbacks. diff --git a/Documentation/video4linux/v4l2-framework.txt b/Documentation/video4linux/v4l2-framework.txt index 75d5c18d689a..fa41608ab2b4 100644 --- a/Documentation/video4linux/v4l2-framework.txt +++ b/Documentation/video4linux/v4l2-framework.txt @@ -295,16 +295,16 @@ module owner. This is done for you if you use the i2c helper functions. If integration with the media framework is needed, you must initialize the media_entity struct embedded in the v4l2_subdev struct (entity field) by -calling media_entity_init(): +calling media_entity_pads_init(), if the entity has pads: struct media_pad *pads = &my_sd->pads; int err; - err = media_entity_init(&sd->entity, npads, pads, 0); + err = media_entity_pads_init(&sd->entity, npads, pads); The pads array must have been previously initialized. There is no need to -manually set the struct media_entity type and name fields, but the revision -field must be initialized if needed. +manually set the struct media_entity function and name fields, but the +revision field must be initialized if needed. A reference to the entity will be automatically acquired/released when the subdev device node (if any) is opened/closed. @@ -695,12 +695,12 @@ difference is that the inode argument is omitted since it is never used. If integration with the media framework is needed, you must initialize the media_entity struct embedded in the video_device struct (entity field) by -calling media_entity_init(): +calling media_entity_pads_init(): struct media_pad *pad = &my_vdev->pad; int err; - err = media_entity_init(&vdev->entity, 1, pad, 0); + err = media_entity_pads_init(&vdev->entity, 1, pad); The pads array must have been previously initialized. There is no need to manually set the struct media_entity type and name fields. diff --git a/Documentation/zh_CN/video4linux/v4l2-framework.txt b/Documentation/zh_CN/video4linux/v4l2-framework.txt index 2b828e631e31..698660b7f21f 100644 --- a/Documentation/zh_CN/video4linux/v4l2-framework.txt +++ b/Documentation/zh_CN/video4linux/v4l2-framework.txt @@ -289,13 +289,13 @@ struct v4l2_subdev_ops { 然后,你必须用一个唯一的名字初始化 subdev->name,并初始化模块的 owner 域。若使用 i2c 辅助函数,这些都会帮你处理好。 -若需同媒体框架整合,你必须调用 media_entity_init() 初始化 v4l2_subdev +若需同媒体框架整合,你必须调用 media_entity_pads_init() 初始化 v4l2_subdev 结构体中的 media_entity 结构体(entity 域): struct media_pad *pads = &my_sd->pads; int err; - err = media_entity_init(&sd->entity, npads, pads, 0); + err = media_entity_pads_init(&sd->entity, npads, pads); pads 数组必须预先初始化。无须手动设置 media_entity 的 type 和 name 域,但如有必要,revision 域必须初始化。 @@ -596,13 +596,13 @@ void v4l2_disable_ioctl(struct video_device *vdev, unsigned int cmd); v4l2_file_operations 结构体是 file_operations 的一个子集。其主要 区别在于:因 inode 参数从未被使用,它将被忽略。 -如果需要与媒体框架整合,你必须通过调用 media_entity_init() 初始化 +如果需要与媒体框架整合,你必须通过调用 media_entity_pads_init() 初始化 嵌入在 video_device 结构体中的 media_entity(entity 域)结构体: struct media_pad *pad = &my_vdev->pad; int err; - err = media_entity_init(&vdev->entity, 1, pad, 0); + err = media_entity_pads_init(&vdev->entity, 1, pad); pads 数组必须预先初始化。没有必要手动设置 media_entity 的 type 和 name 域。 |