[media] DocBook: Document MEDIA_IOC_G_TOPOLOGY
Add description for this new media controller ioctl.
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
diff --git a/Documentation/DocBook/media/v4l/media-controller.xml b/Documentation/DocBook/media/v4l/media-controller.xml
index 63d48de..5f2fc07 100644
--- a/Documentation/DocBook/media/v4l/media-controller.xml
+++ b/Documentation/DocBook/media/v4l/media-controller.xml
@@ -98,6 +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-g-topology.xml b/Documentation/DocBook/media/v4l/media-ioc-g-topology.xml
new file mode 100644
index 0000000..e0d49fa
--- /dev/null
+++ b/Documentation/DocBook/media/v4l/media-ioc-g-topology.xml
@@ -0,0 +1,391 @@
+<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>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>