diff options
Diffstat (limited to 'Documentation/DocBook/media/v4l/vidioc-subdev-g-frame-interval.xml')
| -rw-r--r-- | Documentation/DocBook/media/v4l/vidioc-subdev-g-frame-interval.xml | 141 |
1 files changed, 0 insertions, 141 deletions
diff --git a/Documentation/DocBook/media/v4l/vidioc-subdev-g-frame-interval.xml b/Documentation/DocBook/media/v4l/vidioc-subdev-g-frame-interval.xml deleted file mode 100644 index 0bc3ea22d31f..000000000000 --- a/Documentation/DocBook/media/v4l/vidioc-subdev-g-frame-interval.xml +++ /dev/null @@ -1,141 +0,0 @@ -<refentry id="vidioc-subdev-g-frame-interval"> - <refmeta> - <refentrytitle>ioctl VIDIOC_SUBDEV_G_FRAME_INTERVAL, VIDIOC_SUBDEV_S_FRAME_INTERVAL</refentrytitle> - &manvol; - </refmeta> - - <refnamediv> - <refname>VIDIOC_SUBDEV_G_FRAME_INTERVAL</refname> - <refname>VIDIOC_SUBDEV_S_FRAME_INTERVAL</refname> - <refpurpose>Get or set the frame interval on a subdev pad</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_frame_interval *<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_G_FRAME_INTERVAL, VIDIOC_SUBDEV_S_FRAME_INTERVAL</para> - </listitem> - </varlistentry> - <varlistentry> - <term><parameter>argp</parameter></term> - <listitem> - <para></para> - </listitem> - </varlistentry> - </variablelist> - </refsect1> - - <refsect1> - <title>Description</title> - - <note> - <title>Experimental</title> - <para>This is an <link linkend="experimental">experimental</link> - interface and may change in the future.</para> - </note> - - <para>These ioctls are used to get and set the frame interval at specific - subdev pads in the image pipeline. The frame interval only makes sense for - sub-devices that can control the frame period on their own. This includes, - for instance, image sensors and TV tuners. Sub-devices that don't support - frame intervals must not implement these ioctls.</para> - - <para>To retrieve the current frame interval applications set the - <structfield>pad</structfield> field of a &v4l2-subdev-frame-interval; to - the desired pad number as reported by the media controller API. When they - call the <constant>VIDIOC_SUBDEV_G_FRAME_INTERVAL</constant> ioctl with a - pointer to this structure the driver fills the members of the - <structfield>interval</structfield> field.</para> - - <para>To change the current frame interval applications set both the - <structfield>pad</structfield> field and all members of the - <structfield>interval</structfield> field. When they call the - <constant>VIDIOC_SUBDEV_S_FRAME_INTERVAL</constant> ioctl with a pointer to - this structure the driver verifies the requested interval, adjusts it based - on the hardware capabilities and configures the device. Upon return the - &v4l2-subdev-frame-interval; contains the current frame interval as would be - returned by a <constant>VIDIOC_SUBDEV_G_FRAME_INTERVAL</constant> call. - </para> - - <para>Drivers must not return an error solely because the requested interval - doesn't match the device capabilities. They must instead modify the interval - to match what the hardware can provide. The modified interval should be as - close as possible to the original request.</para> - - <para>Sub-devices that support the frame interval ioctls should implement - them on a single pad only. Their behaviour when supported on multiple pads - of the same sub-device is not defined.</para> - - <table pgwide="1" frame="none" id="v4l2-subdev-frame-interval"> - <title>struct <structname>v4l2_subdev_frame_interval</structname></title> - <tgroup cols="3"> - &cs-str; - <tbody valign="top"> - <row> - <entry>__u32</entry> - <entry><structfield>pad</structfield></entry> - <entry>Pad number as reported by the media controller API.</entry> - </row> - <row> - <entry>&v4l2-fract;</entry> - <entry><structfield>interval</structfield></entry> - <entry>Period, in seconds, between consecutive video frames.</entry> - </row> - <row> - <entry>__u32</entry> - <entry><structfield>reserved</structfield>[9]</entry> - <entry>Reserved for future extensions. Applications and drivers must - set the array to zero.</entry> - </row> - </tbody> - </tgroup> - </table> - </refsect1> - - <refsect1> - &return-value; - - <variablelist> - <varlistentry> - <term><errorcode>EBUSY</errorcode></term> - <listitem> - <para>The frame interval can't be changed because the pad is currently - busy. This can be caused, for instance, by an active video stream on - the pad. The ioctl must not be retried without performing another - action to fix the problem first. Only returned by - <constant>VIDIOC_SUBDEV_S_FRAME_INTERVAL</constant></para> - </listitem> - </varlistentry> - <varlistentry> - <term><errorcode>EINVAL</errorcode></term> - <listitem> - <para>The &v4l2-subdev-frame-interval; <structfield>pad</structfield> - references a non-existing pad, or the pad doesn't support frame - intervals.</para> - </listitem> - </varlistentry> - </variablelist> - </refsect1> -</refentry> |