From: Hans Verkuil <hans.verkuil@xxxxxxxxx>
Add documentation for the new VIDIOC_SUBDEV_QUERYCAP ioctl.
Signed-off-by: Hans Verkuil <hans.verkuil@xxxxxxxxx>
---
Documentation/DocBook/media/v4l/v4l2.xml | 1 +
.../DocBook/media/v4l/vidioc-subdev-querycap.xml | 125 +++++++++++++++++++++
2 files changed, 126 insertions(+)
create mode 100644 Documentation/DocBook/media/v4l/vidioc-subdev-querycap.xml
diff --git a/Documentation/DocBook/media/v4l/v4l2.xml b/Documentation/DocBook/media/v4l/v4l2.xml
index e98caa1..23607bc 100644
--- a/Documentation/DocBook/media/v4l/v4l2.xml
+++ b/Documentation/DocBook/media/v4l/v4l2.xml
@@ -669,6 +669,7 @@ and discussions on the V4L mailing list.</revremark>
&sub-subdev-g-fmt;
&sub-subdev-g-frame-interval;
&sub-subdev-g-selection;
+ &sub-subdev-querycap;
&sub-subscribe-event;
<!-- End of ioctls. -->
&sub-mmap;
diff --git a/Documentation/DocBook/media/v4l/vidioc-subdev-querycap.xml b/Documentation/DocBook/media/v4l/vidioc-subdev-querycap.xml
new file mode 100644
index 0000000..7c4fceb
--- /dev/null
+++ b/Documentation/DocBook/media/v4l/vidioc-subdev-querycap.xml
@@ -0,0 +1,125 @@
+<refentry id="vidioc-subdev-querycap">
+ <refmeta>
+ <refentrytitle>ioctl VIDIOC_SUBDEV_QUERYCAP</refentrytitle>
+ &manvol;
+ </refmeta>
+
+ <refnamediv>
+ <refname>VIDIOC_SUBDEV_QUERYCAP</refname>
+ <refpurpose>Query sub-device capabilities</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 v4l2_subdev_capability *<parameter>argp</parameter></paramdef>
+ </funcprototype>
+ </funcsynopsis>
+ </refsynopsisdiv>
+
+ <refsect1>
+ <title>Arguments</title>
+
+ <variablelist>
+ <varlistentry>
+ <term><parameter>fd</parameter></term>
+ <listitem>
+ <para>&fd;</para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><parameter>request</parameter></term>
+ <listitem>
+ <para>VIDIOC_SUBDEV_QUERYCAP</para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><parameter>argp</parameter></term>
+ <listitem>
+ <para></para>
+ </listitem>
+ </varlistentry>
+ </variablelist>
+ </refsect1>
+
+ <refsect1>
+ <title>Description</title>
+
+ <para>All V4L2 sub-devices support the
+<constant>VIDIOC_SUBDEV_QUERYCAP</constant> ioctl. It is used to identify
+kernel devices compatible with this specification and to obtain
+information about driver and hardware capabilities. The ioctl takes a
+pointer to a &v4l2-subdev-capability; which is filled by the driver. When the
+driver is not compatible with this specification the ioctl returns an
+error, most likely the &ENOTTY;.</para>
+
+ <table pgwide="1" frame="none" id="v4l2-subdev-capability">
+ <title>struct <structname>v4l2_subdev_capability</structname></title>
+ <tgroup cols="3">
+ &cs-str;
+ <tbody valign="top">
+ <row>
+ <entry>__u32</entry>
+ <entry><structfield>version</structfield></entry>
+ <entry><para>Version number of the driver.</para>
+<para>The version reported is provided by the
+V4L2 subsystem following the kernel numbering scheme. However, it
+may not always return the same version as the kernel if, for example,
+a stable or distribution-modified kernel uses the V4L2 stack from a
+newer kernel.</para>
+<para>The version number is formatted using the
+<constant>KERNEL_VERSION()</constant> macro:</para></entry>
+ </row>
+ <row>
+ <entry spanname="hspan"><para>
+<programlisting>
+#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))
+
+__u32 version = KERNEL_VERSION(0, 8, 1);
+
+printf ("Version: %u.%u.%u\n",
+ (version >> 16) & 0xFF,
+ (version >> 8) & 0xFF,
+ version & 0xFF);
+</programlisting></para></entry>
+ </row>
+ <row>
+ <entry>__u32</entry>
+ <entry><structfield>device_caps</structfield></entry>
+ <entry>Sub-device capabilities of the opened device, see <xref
+ linkend="subdevice-capabilities" />.
+ </entry>
+ </row>
+ <row>
+ <entry>__u32</entry>
+ <entry><structfield>reserved</structfield>[50]</entry>
+ <entry>Reserved for future extensions. Drivers must set
+this array to zero.</entry>
+ </row>
+ </tbody>
+ </tgroup>
+ </table>
+
+ <table pgwide="1" frame="none" id="subdevice-capabilities">
+ <title>Sub-Device Capabilities Flags</title>
+ <tgroup cols="3">
+ &cs-def;
+ <tbody valign="top">
+ <row>
+ <entry><constant>V4L2_SUBDEV_CAP_ENTITY</constant></entry>
+ <entry>0x00000001</entry>
+ <entry>The sub-device is a media controller entity. If this
+capability is set, then you can call &MEDIA-IOC-DEVICE-INFO;.</entry>
+ </row>
+ </tbody>
+ </tgroup>
+ </table>
+ </refsect1>
+
+ <refsect1>
+ &return-value;
+ </refsect1>
+</refentry>
--
2.1.4
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