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Diffstat (limited to 'Documentation/DocBook/media/v4l/cec-ioc-dqevent.xml')
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diff --git a/Documentation/DocBook/media/v4l/cec-ioc-dqevent.xml b/Documentation/DocBook/media/v4l/cec-ioc-dqevent.xml deleted file mode 100644 index 697dde575cd4..000000000000 --- a/Documentation/DocBook/media/v4l/cec-ioc-dqevent.xml +++ /dev/null @@ -1,202 +0,0 @@ -<refentry id="cec-ioc-g-event"> - <refmeta> - <refentrytitle>ioctl CEC_DQEVENT</refentrytitle> - &manvol; - </refmeta> - - <refnamediv> - <refname>CEC_DQEVENT</refname> - <refpurpose>Dequeue a CEC 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 cec_event *<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='cec-func-open'><function>open()</function></link>.</para> - </listitem> - </varlistentry> - <varlistentry> - <term><parameter>request</parameter></term> - <listitem> - <para>CEC_DQEVENT</para> - </listitem> - </varlistentry> - <varlistentry> - <term><parameter>argp</parameter></term> - <listitem> - <para></para> - </listitem> - </varlistentry> - </variablelist> - </refsect1> - - <refsect1> - <title>Description</title> - - <para> - Note: this documents the proposed CEC API. This API is not yet finalized and - is currently only available as a staging kernel module. - </para> - - <para>CEC devices can send asynchronous events. These can be retrieved by calling - the <constant>CEC_DQEVENT</constant> ioctl. If the file descriptor is in non-blocking - mode and no event is pending, then it will return -1 and set errno to the &EAGAIN;.</para> - - <para>The internal event queues are per-filehandle and per-event type. If there is - no more room in a queue then the last event is overwritten with the new one. This - means that intermediate results can be thrown away but that the latest event is always - available. This also means that is it possible to read two successive events that have - the same value (e.g. two CEC_EVENT_STATE_CHANGE events with the same state). In that - case the intermediate state changes were lost but it is guaranteed that the state - did change in between the two events.</para> - - <table pgwide="1" frame="none" id="cec-event-state-change"> - <title>struct <structname>cec_event_state_change</structname></title> - <tgroup cols="3"> - &cs-str; - <tbody valign="top"> - <row> - <entry>__u16</entry> - <entry><structfield>phys_addr</structfield></entry> - <entry>The current physical address.</entry> - </row> - <row> - <entry>__u16</entry> - <entry><structfield>log_addr_mask</structfield></entry> - <entry>The current set of claimed logical addresses.</entry> - </row> - </tbody> - </tgroup> - </table> - - <table pgwide="1" frame="none" id="cec-event-lost-msgs"> - <title>struct <structname>cec_event_lost_msgs</structname></title> - <tgroup cols="3"> - &cs-str; - <tbody valign="top"> - <row> - <entry>__u32</entry> - <entry><structfield>lost_msgs</structfield></entry> - <entry>Set to the number of lost messages since the filehandle - was opened or since the last time this event was dequeued for - this filehandle. The messages lost are the oldest messages. So - when a new message arrives and there is no more room, then the - oldest message is discarded to make room for the new one. The - internal size of the message queue guarantees that all messages - received in the last two seconds will be stored. Since messages - should be replied to within a second according to the CEC - specification, this is more than enough. - </entry> - </row> - </tbody> - </tgroup> - </table> - - <table pgwide="1" frame="none" id="cec-event"> - <title>struct <structname>cec_event</structname></title> - <tgroup cols="4"> - &cs-str; - <tbody valign="top"> - <row> - <entry>__u64</entry> - <entry><structfield>ts</structfield></entry> - <entry>Timestamp of the event in ns.</entry> - <entry></entry> - </row> - <row> - <entry>__u32</entry> - <entry><structfield>event</structfield></entry> - <entry>The CEC event type, see <xref linkend="cec-events" />.</entry> - <entry></entry> - </row> - <row> - <entry>__u32</entry> - <entry><structfield>flags</structfield></entry> - <entry>Event flags, see <xref linkend="cec-event-flags" />.</entry> - <entry></entry> - </row> - <row> - <entry>union</entry> - <entry>(anonymous)</entry> - <entry></entry> - <entry></entry> - </row> - <row> - <entry></entry> - <entry>struct cec_event_state_change</entry> - <entry><structfield>state_change</structfield></entry> - <entry>The new adapter state as sent by the <constant>CEC_EVENT_STATE_CHANGE</constant> - event.</entry> - </row> - <row> - <entry></entry> - <entry>struct cec_event_lost_msgs</entry> - <entry><structfield>lost_msgs</structfield></entry> - <entry>The number of lost messages as sent by the <constant>CEC_EVENT_LOST_MSGS</constant> - event.</entry> - </row> - </tbody> - </tgroup> - </table> - - <table pgwide="1" frame="none" id="cec-events"> - <title>CEC Events Types</title> - <tgroup cols="3"> - &cs-def; - <tbody valign="top"> - <row> - <entry><constant>CEC_EVENT_STATE_CHANGE</constant></entry> - <entry>1</entry> - <entry>Generated when the CEC Adapter's state changes. When open() is - called an initial event will be generated for that filehandle with the - CEC Adapter's state at that time. - </entry> - </row> - <row> - <entry><constant>CEC_EVENT_LOST_MSGS</constant></entry> - <entry>2</entry> - <entry>Generated if one or more CEC messages were lost because the - application didn't dequeue CEC messages fast enough.</entry> - </row> - </tbody> - </tgroup> - </table> - - <table pgwide="1" frame="none" id="cec-event-flags"> - <title>CEC Event Flags</title> - <tgroup cols="3"> - &cs-def; - <tbody valign="top"> - <row> - <entry><constant>CEC_EVENT_FL_INITIAL_VALUE</constant></entry> - <entry>1</entry> - <entry>Set for the initial events that are generated when the device is - opened. See the table above for which events do this. This allows - applications to learn the initial state of the CEC adapter at open() - time.</entry> - </row> - </tbody> - </tgroup> - </table> - </refsect1> - - <refsect1> - &return-value; - </refsect1> -</refentry> |