aboutsummaryrefslogtreecommitdiff
path: root/Documentation/DocBook/media/v4l/vidioc-g-priority.xml
diff options
context:
space:
mode:
Diffstat (limited to 'Documentation/DocBook/media/v4l/vidioc-g-priority.xml')
-rw-r--r--Documentation/DocBook/media/v4l/vidioc-g-priority.xml135
1 files changed, 0 insertions, 135 deletions
diff --git a/Documentation/DocBook/media/v4l/vidioc-g-priority.xml b/Documentation/DocBook/media/v4l/vidioc-g-priority.xml
deleted file mode 100644
index 6a81b4fe9538..000000000000
--- a/Documentation/DocBook/media/v4l/vidioc-g-priority.xml
+++ /dev/null
@@ -1,135 +0,0 @@
-<refentry id="vidioc-g-priority">
- <refmeta>
- <refentrytitle>ioctl VIDIOC_G_PRIORITY, VIDIOC_S_PRIORITY</refentrytitle>
- &manvol;
- </refmeta>
-
- <refnamediv>
- <refname>VIDIOC_G_PRIORITY</refname>
- <refname>VIDIOC_S_PRIORITY</refname>
- <refpurpose>Query or request the access priority associated with a
-file descriptor</refpurpose>
- </refnamediv>
-
- <refsynopsisdiv>
- <funcsynopsis>
- <funcprototype>
- <funcdef>int <function>ioctl</function></funcdef>
- <paramdef>int <parameter>fd</parameter></paramdef>
- <paramdef>int <parameter>request</parameter></paramdef>
- <paramdef>enum v4l2_priority *<parameter>argp</parameter></paramdef>
- </funcprototype>
- </funcsynopsis>
- <funcsynopsis>
- <funcprototype>
- <funcdef>int <function>ioctl</function></funcdef>
- <paramdef>int <parameter>fd</parameter></paramdef>
- <paramdef>int <parameter>request</parameter></paramdef>
- <paramdef>const enum v4l2_priority *<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_G_PRIORITY, VIDIOC_S_PRIORITY</para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><parameter>argp</parameter></term>
- <listitem>
- <para>Pointer to an enum v4l2_priority type.</para>
- </listitem>
- </varlistentry>
- </variablelist>
- </refsect1>
-
- <refsect1>
- <title>Description</title>
-
- <para>To query the current access priority
-applications call the <constant>VIDIOC_G_PRIORITY</constant> ioctl
-with a pointer to an enum v4l2_priority variable where the driver stores
-the current priority.</para>
-
- <para>To request an access priority applications store the
-desired priority in an enum v4l2_priority variable and call
-<constant>VIDIOC_S_PRIORITY</constant> ioctl with a pointer to this
-variable.</para>
-
- <table frame="none" pgwide="1" id="v4l2-priority">
- <title>enum v4l2_priority</title>
- <tgroup cols="3">
- &cs-def;
- <tbody valign="top">
- <row>
- <entry><constant>V4L2_PRIORITY_UNSET</constant></entry>
- <entry>0</entry>
- <entry></entry>
- </row>
- <row>
- <entry><constant>V4L2_PRIORITY_BACKGROUND</constant></entry>
- <entry>1</entry>
- <entry>Lowest priority, usually applications running in
-background, for example monitoring VBI transmissions. A proxy
-application running in user space will be necessary if multiple
-applications want to read from a device at this priority.</entry>
- </row>
- <row>
- <entry><constant>V4L2_PRIORITY_INTERACTIVE</constant></entry>
- <entry>2</entry>
- <entry></entry>
- </row>
- <row>
- <entry><constant>V4L2_PRIORITY_DEFAULT</constant></entry>
- <entry>2</entry>
- <entry>Medium priority, usually applications started and
-interactively controlled by the user. For example TV viewers, Teletext
-browsers, or just "panel" applications to change the channel or video
-controls. This is the default priority unless an application requests
-another.</entry>
- </row>
- <row>
- <entry><constant>V4L2_PRIORITY_RECORD</constant></entry>
- <entry>3</entry>
- <entry>Highest priority. Only one file descriptor can have
-this priority, it blocks any other fd from changing device properties.
-Usually applications which must not be interrupted, like video
-recording.</entry>
- </row>
- </tbody>
- </tgroup>
- </table>
- </refsect1>
-
- <refsect1>
- &return-value;
-
- <variablelist>
- <varlistentry>
- <term><errorcode>EINVAL</errorcode></term>
- <listitem>
- <para>The requested priority value is invalid.</para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><errorcode>EBUSY</errorcode></term>
- <listitem>
- <para>Another application already requested higher
-priority.</para>
- </listitem>
- </varlistentry>
- </variablelist>
- </refsect1>
-</refentry>