be0270ec89
There are a few discussions left with regards to this ioctl: 1) the name of the new structs will contain _v2_ on it? 2) what's the best alternative to avoid compat32 issues? Due to that, let's postpone the addition of this new ioctl to the next Kernel version, to give people more time to discuss it. Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
395 lines
12 KiB
XML
395 lines
12 KiB
XML
<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>
|