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Diffstat (limited to 'Documentation/DocBook/media/v4l/vidioc-dqevent.xml')
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diff --git a/Documentation/DocBook/media/v4l/vidioc-dqevent.xml b/Documentation/DocBook/media/v4l/vidioc-dqevent.xml deleted file mode 100644 index c9c3c7713832..000000000000 --- a/Documentation/DocBook/media/v4l/vidioc-dqevent.xml +++ /dev/null @@ -1,471 +0,0 @@ -<refentry id="vidioc-dqevent"> - <refmeta> - <refentrytitle>ioctl VIDIOC_DQEVENT</refentrytitle> - &manvol; - </refmeta> - - <refnamediv> - <refname>VIDIOC_DQEVENT</refname> - <refpurpose>Dequeue 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 -*<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_DQEVENT</para> - </listitem> - </varlistentry> - <varlistentry> - <term><parameter>argp</parameter></term> - <listitem> - <para></para> - </listitem> - </varlistentry> - </variablelist> - </refsect1> - - <refsect1> - <title>Description</title> - - <para>Dequeue an event from a video device. No input is required - for this ioctl. All the fields of the &v4l2-event; structure are - filled by the driver. The file handle will also receive exceptions - which the application may get by e.g. using the select system - call.</para> - - <table frame="none" pgwide="1" id="v4l2-event"> - <title>struct <structname>v4l2_event</structname></title> - <tgroup cols="4"> - &cs-str; - <tbody valign="top"> - <row> - <entry>__u32</entry> - <entry><structfield>type</structfield></entry> - <entry></entry> - <entry>Type of the event, see <xref linkend="event-type" />.</entry> - </row> - <row> - <entry>union</entry> - <entry><structfield>u</structfield></entry> - <entry></entry> - <entry></entry> - </row> - <row> - <entry></entry> - <entry>&v4l2-event-vsync;</entry> - <entry><structfield>vsync</structfield></entry> - <entry>Event data for event <constant>V4L2_EVENT_VSYNC</constant>. - </entry> - </row> - <row> - <entry></entry> - <entry>&v4l2-event-ctrl;</entry> - <entry><structfield>ctrl</structfield></entry> - <entry>Event data for event <constant>V4L2_EVENT_CTRL</constant>. - </entry> - </row> - <row> - <entry></entry> - <entry>&v4l2-event-frame-sync;</entry> - <entry><structfield>frame_sync</structfield></entry> - <entry>Event data for event - <constant>V4L2_EVENT_FRAME_SYNC</constant>.</entry> - </row> - <row> - <entry></entry> - <entry>&v4l2-event-motion-det;</entry> - <entry><structfield>motion_det</structfield></entry> - <entry>Event data for event V4L2_EVENT_MOTION_DET.</entry> - </row> - <row> - <entry></entry> - <entry>&v4l2-event-src-change;</entry> - <entry><structfield>src_change</structfield></entry> - <entry>Event data for event V4L2_EVENT_SOURCE_CHANGE.</entry> - </row> - <row> - <entry></entry> - <entry>__u8</entry> - <entry><structfield>data</structfield>[64]</entry> - <entry>Event data. Defined by the event type. The union - should be used to define easily accessible type for - events.</entry> - </row> - <row> - <entry>__u32</entry> - <entry><structfield>pending</structfield></entry> - <entry></entry> - <entry>Number of pending events excluding this one.</entry> - </row> - <row> - <entry>__u32</entry> - <entry><structfield>sequence</structfield></entry> - <entry></entry> - <entry>Event sequence number. The sequence number is - incremented for every subscribed event that takes place. - If sequence numbers are not contiguous it means that - events have been lost. - </entry> - </row> - <row> - <entry>struct timespec</entry> - <entry><structfield>timestamp</structfield></entry> - <entry></entry> - <entry>Event timestamp. The timestamp has been taken from the - <constant>CLOCK_MONOTONIC</constant> clock. To access the - same clock outside V4L2, use <function>clock_gettime(2)</function>. - </entry> - </row> - <row> - <entry>u32</entry> - <entry><structfield>id</structfield></entry> - <entry></entry> - <entry>The ID associated with the event source. If the event does not - have an associated ID (this depends on the event type), then this - is 0.</entry> - </row> - <row> - <entry>__u32</entry> - <entry><structfield>reserved</structfield>[8]</entry> - <entry></entry> - <entry>Reserved for future extensions. Drivers must set - the array to zero.</entry> - </row> - </tbody> - </tgroup> - </table> - - <table frame="none" pgwide="1" id="event-type"> - <title>Event Types</title> - <tgroup cols="3"> - &cs-def; - <tbody valign="top"> - <row> - <entry><constant>V4L2_EVENT_ALL</constant></entry> - <entry>0</entry> - <entry>All events. V4L2_EVENT_ALL is valid only for - VIDIOC_UNSUBSCRIBE_EVENT for unsubscribing all events at once. - </entry> - </row> - <row> - <entry><constant>V4L2_EVENT_VSYNC</constant></entry> - <entry>1</entry> - <entry>This event is triggered on the vertical sync. - This event has a &v4l2-event-vsync; associated with it. - </entry> - </row> - <row> - <entry><constant>V4L2_EVENT_EOS</constant></entry> - <entry>2</entry> - <entry>This event is triggered when the end of a stream is reached. - This is typically used with MPEG decoders to report to the application - when the last of the MPEG stream has been decoded. - </entry> - </row> - <row> - <entry><constant>V4L2_EVENT_CTRL</constant></entry> - <entry>3</entry> - <entry><para>This event requires that the <structfield>id</structfield> - matches the control ID from which you want to receive events. - This event is triggered if the control's value changes, if a - button control is pressed or if the control's flags change. - This event has a &v4l2-event-ctrl; associated with it. This struct - contains much of the same information as &v4l2-queryctrl; and - &v4l2-control;.</para> - - <para>If the event is generated due to a call to &VIDIOC-S-CTRL; or - &VIDIOC-S-EXT-CTRLS;, then the event will <emphasis>not</emphasis> be sent to - the file handle that called the ioctl function. This prevents - nasty feedback loops. If you <emphasis>do</emphasis> want to get the - event, then set the <constant>V4L2_EVENT_SUB_FL_ALLOW_FEEDBACK</constant> - flag. - </para> - - <para>This event type will ensure that no information is lost when - more events are raised than there is room internally. In that - case the &v4l2-event-ctrl; of the second-oldest event is kept, - but the <structfield>changes</structfield> field of the - second-oldest event is ORed with the <structfield>changes</structfield> - field of the oldest event.</para> - </entry> - </row> - <row> - <entry><constant>V4L2_EVENT_FRAME_SYNC</constant></entry> - <entry>4</entry> - <entry> - <para>Triggered immediately when the reception of a - frame has begun. This event has a - &v4l2-event-frame-sync; associated with it.</para> - - <para>If the hardware needs to be stopped in the case of a - buffer underrun it might not be able to generate this event. - In such cases the <structfield>frame_sequence</structfield> - field in &v4l2-event-frame-sync; will not be incremented. This - causes two consecutive frame sequence numbers to have n times - frame interval in between them.</para> - </entry> - </row> - <row> - <entry><constant>V4L2_EVENT_SOURCE_CHANGE</constant></entry> - <entry>5</entry> - <entry> - <para>This event is triggered when a source parameter change is - detected during runtime by the video device. It can be a - runtime resolution change triggered by a video decoder or the - format change happening on an input connector. - This event requires that the <structfield>id</structfield> - matches the input index (when used with a video device node) - or the pad index (when used with a subdevice node) from which - you want to receive events.</para> - - <para>This event has a &v4l2-event-src-change; associated - with it. The <structfield>changes</structfield> bitfield denotes - what has changed for the subscribed pad. If multiple events - occurred before application could dequeue them, then the changes - will have the ORed value of all the events generated.</para> - </entry> - </row> - <row> - <entry><constant>V4L2_EVENT_MOTION_DET</constant></entry> - <entry>6</entry> - <entry> - <para>Triggered whenever the motion detection state for one or more of the regions - changes. This event has a &v4l2-event-motion-det; associated with it.</para> - </entry> - </row> - <row> - <entry><constant>V4L2_EVENT_PRIVATE_START</constant></entry> - <entry>0x08000000</entry> - <entry>Base event number for driver-private events.</entry> - </row> - </tbody> - </tgroup> - </table> - - <table frame="none" pgwide="1" id="v4l2-event-vsync"> - <title>struct <structname>v4l2_event_vsync</structname></title> - <tgroup cols="3"> - &cs-str; - <tbody valign="top"> - <row> - <entry>__u8</entry> - <entry><structfield>field</structfield></entry> - <entry>The upcoming field. See &v4l2-field;.</entry> - </row> - </tbody> - </tgroup> - </table> - - <table frame="none" pgwide="1" id="v4l2-event-ctrl"> - <title>struct <structname>v4l2_event_ctrl</structname></title> - <tgroup cols="4"> - &cs-str; - <tbody valign="top"> - <row> - <entry>__u32</entry> - <entry><structfield>changes</structfield></entry> - <entry></entry> - <entry>A bitmask that tells what has changed. See <xref linkend="ctrl-changes-flags" />.</entry> - </row> - <row> - <entry>__u32</entry> - <entry><structfield>type</structfield></entry> - <entry></entry> - <entry>The type of the control. See &v4l2-ctrl-type;.</entry> - </row> - <row> - <entry>union (anonymous)</entry> - <entry></entry> - <entry></entry> - <entry></entry> - </row> - <row> - <entry></entry> - <entry>__s32</entry> - <entry><structfield>value</structfield></entry> - <entry>The 32-bit value of the control for 32-bit control types. - This is 0 for string controls since the value of a string - cannot be passed using &VIDIOC-DQEVENT;.</entry> - </row> - <row> - <entry></entry> - <entry>__s64</entry> - <entry><structfield>value64</structfield></entry> - <entry>The 64-bit value of the control for 64-bit control types.</entry> - </row> - <row> - <entry>__u32</entry> - <entry><structfield>flags</structfield></entry> - <entry></entry> - <entry>The control flags. See <xref linkend="control-flags" />.</entry> - </row> - <row> - <entry>__s32</entry> - <entry><structfield>minimum</structfield></entry> - <entry></entry> - <entry>The minimum value of the control. See &v4l2-queryctrl;.</entry> - </row> - <row> - <entry>__s32</entry> - <entry><structfield>maximum</structfield></entry> - <entry></entry> - <entry>The maximum value of the control. See &v4l2-queryctrl;.</entry> - </row> - <row> - <entry>__s32</entry> - <entry><structfield>step</structfield></entry> - <entry></entry> - <entry>The step value of the control. See &v4l2-queryctrl;.</entry> - </row> - <row> - <entry>__s32</entry> - <entry><structfield>default_value</structfield></entry> - <entry></entry> - <entry>The default value value of the control. See &v4l2-queryctrl;.</entry> - </row> - </tbody> - </tgroup> - </table> - - <table frame="none" pgwide="1" id="v4l2-event-frame-sync"> - <title>struct <structname>v4l2_event_frame_sync</structname></title> - <tgroup cols="3"> - &cs-str; - <tbody valign="top"> - <row> - <entry>__u32</entry> - <entry><structfield>frame_sequence</structfield></entry> - <entry> - The sequence number of the frame being received. - </entry> - </row> - </tbody> - </tgroup> - </table> - - <table frame="none" pgwide="1" id="v4l2-event-src-change"> - <title>struct <structname>v4l2_event_src_change</structname></title> - <tgroup cols="3"> - &cs-str; - <tbody valign="top"> - <row> - <entry>__u32</entry> - <entry><structfield>changes</structfield></entry> - <entry> - A bitmask that tells what has changed. See <xref linkend="src-changes-flags" />. - </entry> - </row> - </tbody> - </tgroup> - </table> - - <table frame="none" pgwide="1" id="v4l2-event-motion-det"> - <title>struct <structname>v4l2_event_motion_det</structname></title> - <tgroup cols="3"> - &cs-str; - <tbody valign="top"> - <row> - <entry>__u32</entry> - <entry><structfield>flags</structfield></entry> - <entry> - Currently only one flag is available: if <constant>V4L2_EVENT_MD_FL_HAVE_FRAME_SEQ</constant> - is set, then the <structfield>frame_sequence</structfield> field is valid, - otherwise that field should be ignored. - </entry> - </row> - <row> - <entry>__u32</entry> - <entry><structfield>frame_sequence</structfield></entry> - <entry> - The sequence number of the frame being received. Only valid if the - <constant>V4L2_EVENT_MD_FL_HAVE_FRAME_SEQ</constant> flag was set. - </entry> - </row> - <row> - <entry>__u32</entry> - <entry><structfield>region_mask</structfield></entry> - <entry> - The bitmask of the regions that reported motion. There is at least one - region. If this field is 0, then no motion was detected at all. - If there is no <constant>V4L2_CID_DETECT_MD_REGION_GRID</constant> control - (see <xref linkend="detect-controls" />) to assign a different region - to each cell in the motion detection grid, then that all cells - are automatically assigned to the default region 0. - </entry> - </row> - </tbody> - </tgroup> - </table> - - <table pgwide="1" frame="none" id="ctrl-changes-flags"> - <title>Control Changes</title> - <tgroup cols="3"> - &cs-def; - <tbody valign="top"> - <row> - <entry><constant>V4L2_EVENT_CTRL_CH_VALUE</constant></entry> - <entry>0x0001</entry> - <entry>This control event was triggered because the value of the control - changed. Special cases: Volatile controls do no generate this event; - If a control has the <constant>V4L2_CTRL_FLAG_EXECUTE_ON_WRITE</constant> - flag set, then this event is sent as well, regardless its value.</entry> - </row> - <row> - <entry><constant>V4L2_EVENT_CTRL_CH_FLAGS</constant></entry> - <entry>0x0002</entry> - <entry>This control event was triggered because the control flags - changed.</entry> - </row> - <row> - <entry><constant>V4L2_EVENT_CTRL_CH_RANGE</constant></entry> - <entry>0x0004</entry> - <entry>This control event was triggered because the minimum, - maximum, step or the default value of the control changed.</entry> - </row> - </tbody> - </tgroup> - </table> - - <table pgwide="1" frame="none" id="src-changes-flags"> - <title>Source Changes</title> - <tgroup cols="3"> - &cs-def; - <tbody valign="top"> - <row> - <entry><constant>V4L2_EVENT_SRC_CH_RESOLUTION</constant></entry> - <entry>0x0001</entry> - <entry>This event gets triggered when a resolution change is - detected at an input. This can come from an input connector or - from a video decoder. - </entry> - </row> - </tbody> - </tgroup> - </table> - </refsect1> - <refsect1> - &return-value; - </refsect1> -</refentry> |