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Diffstat (limited to 'Documentation/DocBook/media/v4l/vidioc-query-dv-timings.xml')
| -rw-r--r-- | Documentation/DocBook/media/v4l/vidioc-query-dv-timings.xml | 115 |
1 files changed, 0 insertions, 115 deletions
diff --git a/Documentation/DocBook/media/v4l/vidioc-query-dv-timings.xml b/Documentation/DocBook/media/v4l/vidioc-query-dv-timings.xml deleted file mode 100644 index d41bf47ee5a2..000000000000 --- a/Documentation/DocBook/media/v4l/vidioc-query-dv-timings.xml +++ /dev/null @@ -1,115 +0,0 @@ -<refentry id="vidioc-query-dv-timings"> - <refmeta> - <refentrytitle>ioctl VIDIOC_QUERY_DV_TIMINGS</refentrytitle> - &manvol; - </refmeta> - - <refnamediv> - <refname>VIDIOC_QUERY_DV_TIMINGS</refname> - <refname>VIDIOC_SUBDEV_QUERY_DV_TIMINGS</refname> - <refpurpose>Sense the DV preset received by the current -input</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_dv_timings *<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_QUERY_DV_TIMINGS, VIDIOC_SUBDEV_QUERY_DV_TIMINGS</para> - </listitem> - </varlistentry> - <varlistentry> - <term><parameter>argp</parameter></term> - <listitem> - <para></para> - </listitem> - </varlistentry> - </variablelist> - </refsect1> - - <refsect1> - <title>Description</title> - - <para>The hardware may be able to detect the current DV timings -automatically, similar to sensing the video standard. To do so, applications -call <constant>VIDIOC_QUERY_DV_TIMINGS</constant> with a pointer to a -&v4l2-dv-timings;. Once the hardware detects the timings, it will fill in the -timings structure.</para> - -<para>Please note that drivers shall <emphasis>not</emphasis> switch timings automatically -if new timings are detected. Instead, drivers should send the -<constant>V4L2_EVENT_SOURCE_CHANGE</constant> event (if they support this) and expect -that userspace will take action by calling <constant>VIDIOC_QUERY_DV_TIMINGS</constant>. -The reason is that new timings usually mean different buffer sizes as well, and you -cannot change buffer sizes on the fly. In general, applications that receive the -Source Change event will have to call <constant>VIDIOC_QUERY_DV_TIMINGS</constant>, -and if the detected timings are valid they will have to stop streaming, set the new -timings, allocate new buffers and start streaming again.</para> - -<para>If the timings could not be detected because there was no signal, then -<errorcode>ENOLINK</errorcode> is returned. If a signal was detected, but -it was unstable and the receiver could not lock to the signal, then -<errorcode>ENOLCK</errorcode> is returned. If the receiver could lock to the signal, -but the format is unsupported (e.g. because the pixelclock is out of range -of the hardware capabilities), then the driver fills in whatever timings it -could find and returns <errorcode>ERANGE</errorcode>. In that case the application -can call &VIDIOC-DV-TIMINGS-CAP; to compare the found timings with the hardware's -capabilities in order to give more precise feedback to the user. -</para> - </refsect1> - - <refsect1> - &return-value; - - <variablelist> - <varlistentry> - <term><errorcode>ENODATA</errorcode></term> - <listitem> - <para>Digital video timings are not supported for this input or output.</para> - </listitem> - </varlistentry> - <varlistentry> - <term><errorcode>ENOLINK</errorcode></term> - <listitem> - <para>No timings could be detected because no signal was found. -</para> - </listitem> - </varlistentry> - <varlistentry> - <term><errorcode>ENOLCK</errorcode></term> - <listitem> - <para>The signal was unstable and the hardware could not lock on to it. -</para> - </listitem> - </varlistentry> - <varlistentry> - <term><errorcode>ERANGE</errorcode></term> - <listitem> - <para>Timings were found, but they are out of range of the hardware -capabilities. -</para> - </listitem> - </varlistentry> - </variablelist> - </refsect1> -</refentry> |