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authorMauro Carvalho Chehab <mchehab@s-opensource.com>2016-07-27 06:32:31 -0300
committerMauro Carvalho Chehab <mchehab@s-opensource.com>2016-07-28 20:08:19 -0300
commit43f71d93a0cb342f0c918fba3f6abb7661e40ad2 (patch)
treea1dc7288bc480e7027ca1827ca4876472fa12e40 /Documentation/DocBook/media/v4l/vidioc-subscribe-event.xml
parentff9a082fda424257976f08fce942609f358015e0 (diff)
doc-rst: Remove the media docbook
Now that all media documentation was converted to Sphinx, we should get rid of the old DocBook one, as we don't want people to submit patches against the old stuff. Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com> Acked-by: Hans Verkuil <hans.verkuil@cisco.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
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diff --git a/Documentation/DocBook/media/v4l/vidioc-subscribe-event.xml b/Documentation/DocBook/media/v4l/vidioc-subscribe-event.xml
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--- a/Documentation/DocBook/media/v4l/vidioc-subscribe-event.xml
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-<refentry id="vidioc-subscribe-event">
- <refmeta>
- <refentrytitle>ioctl VIDIOC_SUBSCRIBE_EVENT, VIDIOC_UNSUBSCRIBE_EVENT</refentrytitle>
- &manvol;
- </refmeta>
-
- <refnamediv>
- <refname>VIDIOC_SUBSCRIBE_EVENT</refname>
- <refname>VIDIOC_UNSUBSCRIBE_EVENT</refname>
- <refpurpose>Subscribe or unsubscribe event</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_event_subscription
-*<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_SUBSCRIBE_EVENT, VIDIOC_UNSUBSCRIBE_EVENT</para>
- </listitem>
- </varlistentry>
- <varlistentry>
- <term><parameter>argp</parameter></term>
- <listitem>
- <para></para>
- </listitem>
- </varlistentry>
- </variablelist>
- </refsect1>
-
- <refsect1>
- <title>Description</title>
-
- <para>Subscribe or unsubscribe V4L2 event. Subscribed events are
- dequeued by using the &VIDIOC-DQEVENT; ioctl.</para>
-
- <table frame="none" pgwide="1" id="v4l2-event-subscription">
- <title>struct <structname>v4l2_event_subscription</structname></title>
- <tgroup cols="3">
- &cs-str;
- <tbody valign="top">
- <row>
- <entry>__u32</entry>
- <entry><structfield>type</structfield></entry>
- <entry>Type of the event, see <xref linkend="event-type" />. Note that
-<constant>V4L2_EVENT_ALL</constant> can be used with VIDIOC_UNSUBSCRIBE_EVENT
-for unsubscribing all events at once.</entry>
- </row>
- <row>
- <entry>__u32</entry>
- <entry><structfield>id</structfield></entry>
- <entry>ID of the event source. If there is no ID associated with
- the event source, then set this to 0. Whether or not an event
- needs an ID depends on the event type.</entry>
- </row>
- <row>
- <entry>__u32</entry>
- <entry><structfield>flags</structfield></entry>
- <entry>Event flags, see <xref linkend="event-flags" />.</entry>
- </row>
- <row>
- <entry>__u32</entry>
- <entry><structfield>reserved</structfield>[5]</entry>
- <entry>Reserved for future extensions. Drivers and applications
- must set the array to zero.</entry>
- </row>
- </tbody>
- </tgroup>
- </table>
-
- <table pgwide="1" frame="none" id="event-flags">
- <title>Event Flags</title>
- <tgroup cols="3">
- &cs-def;
- <tbody valign="top">
- <row>
- <entry><constant>V4L2_EVENT_SUB_FL_SEND_INITIAL</constant></entry>
- <entry>0x0001</entry>
- <entry>When this event is subscribed an initial event will be sent
- containing the current status. This only makes sense for events
- that are triggered by a status change such as <constant>V4L2_EVENT_CTRL</constant>.
- Other events will ignore this flag.</entry>
- </row>
- <row>
- <entry><constant>V4L2_EVENT_SUB_FL_ALLOW_FEEDBACK</constant></entry>
- <entry>0x0002</entry>
- <entry><para>If set, then events directly caused by an ioctl will also be sent to
- the filehandle that called that ioctl. For example, changing a control using
- &VIDIOC-S-CTRL; will cause a V4L2_EVENT_CTRL to be sent back to that same
- filehandle. Normally such events are suppressed to prevent feedback loops
- where an application changes a control to a one value and then another, and
- then receives an event telling it that that control has changed to the first
- value.</para>
-
- <para>Since it can't tell whether that event was caused by another application
- or by the &VIDIOC-S-CTRL; call it is hard to decide whether to set the
- control to the value in the event, or ignore it.</para>
-
- <para>Think carefully when you set this flag so you won't get into situations
- like that.</para>
- </entry>
- </row>
- </tbody>
- </tgroup>
- </table>
-
- </refsect1>
- <refsect1>
- &return-value;
- </refsect1>
-</refentry>