| <refentry id="vidioc-enuminput"> |
| <refmeta> |
| <refentrytitle>ioctl VIDIOC_ENUMINPUT</refentrytitle> |
| &manvol; |
| </refmeta> |
| |
| <refnamediv> |
| <refname>VIDIOC_ENUMINPUT</refname> |
| <refpurpose>Enumerate video inputs</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_input |
| *<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_ENUMINPUT</para> |
| </listitem> |
| </varlistentry> |
| <varlistentry> |
| <term><parameter>argp</parameter></term> |
| <listitem> |
| <para></para> |
| </listitem> |
| </varlistentry> |
| </variablelist> |
| </refsect1> |
| |
| <refsect1> |
| <title>Description</title> |
| |
| <para>To query the attributes of a video input applications |
| initialize the <structfield>index</structfield> field of &v4l2-input; |
| and call the <constant>VIDIOC_ENUMINPUT</constant> ioctl with a |
| pointer to this structure. Drivers fill the rest of the structure or |
| return an &EINVAL; when the index is out of bounds. To enumerate all |
| inputs applications shall begin at index zero, incrementing by one |
| until the driver returns <errorcode>EINVAL</errorcode>.</para> |
| |
| <table frame="none" pgwide="1" id="v4l2-input"> |
| <title>struct <structname>v4l2_input</structname></title> |
| <tgroup cols="3"> |
| &cs-str; |
| <tbody valign="top"> |
| <row> |
| <entry>__u32</entry> |
| <entry><structfield>index</structfield></entry> |
| <entry>Identifies the input, set by the |
| application.</entry> |
| </row> |
| <row> |
| <entry>__u8</entry> |
| <entry><structfield>name</structfield>[32]</entry> |
| <entry>Name of the video input, a NUL-terminated ASCII |
| string, for example: "Vin (Composite 2)". This information is intended |
| for the user, preferably the connector label on the device itself.</entry> |
| </row> |
| <row> |
| <entry>__u32</entry> |
| <entry><structfield>type</structfield></entry> |
| <entry>Type of the input, see <xref |
| linkend="input-type" />.</entry> |
| </row> |
| <row> |
| <entry>__u32</entry> |
| <entry><structfield>audioset</structfield></entry> |
| <entry><para>Drivers can enumerate up to 32 video and |
| audio inputs. This field shows which audio inputs were selectable as |
| audio source if this was the currently selected video input. It is a |
| bit mask. The LSB corresponds to audio input 0, the MSB to input 31. |
| Any number of bits can be set, or none.</para><para>When the driver |
| does not enumerate audio inputs no bits must be set. Applications |
| shall not interpret this as lack of audio support. Some drivers |
| automatically select audio sources and do not enumerate them since |
| there is no choice anyway.</para><para>For details on audio inputs and |
| how to select the current input see <xref |
| linkend="audio" />.</para></entry> |
| </row> |
| <row> |
| <entry>__u32</entry> |
| <entry><structfield>tuner</structfield></entry> |
| <entry>Capture devices can have zero or more tuners (RF |
| demodulators). When the <structfield>type</structfield> is set to |
| <constant>V4L2_INPUT_TYPE_TUNER</constant> this is an RF connector and |
| this field identifies the tuner. It corresponds to |
| &v4l2-tuner; field <structfield>index</structfield>. For details on |
| tuners see <xref linkend="tuner" />.</entry> |
| </row> |
| <row> |
| <entry>&v4l2-std-id;</entry> |
| <entry><structfield>std</structfield></entry> |
| <entry>Every video input supports one or more different |
| video standards. This field is a set of all supported standards. For |
| details on video standards and how to switch see <xref |
| linkend="standard" />.</entry> |
| </row> |
| <row> |
| <entry>__u32</entry> |
| <entry><structfield>status</structfield></entry> |
| <entry>This field provides status information about the |
| input. See <xref linkend="input-status" /> for flags. |
| With the exception of the sensor orientation bits <structfield>status</structfield> is only valid when this is the |
| current input.</entry> |
| </row> |
| <row> |
| <entry>__u32</entry> |
| <entry><structfield>capabilities</structfield></entry> |
| <entry>This field provides capabilities for the |
| input. See <xref linkend="input-capabilities" /> for flags.</entry> |
| </row> |
| <row> |
| <entry>__u32</entry> |
| <entry><structfield>reserved</structfield>[3]</entry> |
| <entry>Reserved for future extensions. Drivers must set |
| the array to zero.</entry> |
| </row> |
| </tbody> |
| </tgroup> |
| </table> |
| |
| <table frame="none" pgwide="1" id="input-type"> |
| <title>Input Types</title> |
| <tgroup cols="3"> |
| &cs-def; |
| <tbody valign="top"> |
| <row> |
| <entry><constant>V4L2_INPUT_TYPE_TUNER</constant></entry> |
| <entry>1</entry> |
| <entry>This input uses a tuner (RF demodulator).</entry> |
| </row> |
| <row> |
| <entry><constant>V4L2_INPUT_TYPE_CAMERA</constant></entry> |
| <entry>2</entry> |
| <entry>Analog baseband input, for example CVBS / |
| Composite Video, S-Video, RGB.</entry> |
| </row> |
| </tbody> |
| </tgroup> |
| </table> |
| |
| <!-- Status flags based on proposal by Mark McClelland, |
| video4linux-list@redhat.com on 18 Oct 2002, subject "Re: [V4L] Re: |
| v4l2 api". "Why are some of them inverted? So that the driver doesn't |
| have to lie about the status in cases where it can't tell one way or |
| the other. Plus, a status of zero would generally mean that everything |
| is OK." --> |
| |
| <table frame="none" pgwide="1" id="input-status"> |
| <title>Input Status Flags</title> |
| <tgroup cols="3"> |
| <colspec colname="c1" /> |
| <colspec colname="c2" align="center" /> |
| <colspec colname="c3" /> |
| <spanspec namest="c1" nameend="c3" spanname="hspan" |
| align="left" /> |
| <tbody valign="top"> |
| <row> |
| <entry spanname="hspan">General</entry> |
| </row> |
| <row> |
| <entry><constant>V4L2_IN_ST_NO_POWER</constant></entry> |
| <entry>0x00000001</entry> |
| <entry>Attached device is off.</entry> |
| </row> |
| <row> |
| <entry><constant>V4L2_IN_ST_NO_SIGNAL</constant></entry> |
| <entry>0x00000002</entry> |
| <entry></entry> |
| </row> |
| <row> |
| <entry><constant>V4L2_IN_ST_NO_COLOR</constant></entry> |
| <entry>0x00000004</entry> |
| <entry>The hardware supports color decoding, but does not |
| detect color modulation in the signal.</entry> |
| </row> |
| <row> |
| <entry spanname="hspan">Sensor Orientation</entry> |
| </row> |
| <row> |
| <entry><constant>V4L2_IN_ST_HFLIP</constant></entry> |
| <entry>0x00000010</entry> |
| <entry>The input is connected to a device that produces a signal |
| that is flipped horizontally and does not correct this before passing the |
| signal to userspace.</entry> |
| </row> |
| <row> |
| <entry><constant>V4L2_IN_ST_VFLIP</constant></entry> |
| <entry>0x00000020</entry> |
| <entry>The input is connected to a device that produces a signal |
| that is flipped vertically and does not correct this before passing the |
| signal to userspace. Note that a 180 degree rotation is the same as HFLIP | VFLIP</entry> |
| </row> |
| <row> |
| <entry spanname="hspan">Analog Video</entry> |
| </row> |
| <row> |
| <entry><constant>V4L2_IN_ST_NO_H_LOCK</constant></entry> |
| <entry>0x00000100</entry> |
| <entry>No horizontal sync lock.</entry> |
| </row> |
| <row> |
| <entry><constant>V4L2_IN_ST_COLOR_KILL</constant></entry> |
| <entry>0x00000200</entry> |
| <entry>A color killer circuit automatically disables color |
| decoding when it detects no color modulation. When this flag is set |
| the color killer is enabled <emphasis>and</emphasis> has shut off |
| color decoding.</entry> |
| </row> |
| <row> |
| <entry spanname="hspan">Digital Video</entry> |
| </row> |
| <row> |
| <entry><constant>V4L2_IN_ST_NO_SYNC</constant></entry> |
| <entry>0x00010000</entry> |
| <entry>No synchronization lock.</entry> |
| </row> |
| <row> |
| <entry><constant>V4L2_IN_ST_NO_EQU</constant></entry> |
| <entry>0x00020000</entry> |
| <entry>No equalizer lock.</entry> |
| </row> |
| <row> |
| <entry><constant>V4L2_IN_ST_NO_CARRIER</constant></entry> |
| <entry>0x00040000</entry> |
| <entry>Carrier recovery failed.</entry> |
| </row> |
| <row> |
| <entry spanname="hspan">VCR and Set-Top Box</entry> |
| </row> |
| <row> |
| <entry><constant>V4L2_IN_ST_MACROVISION</constant></entry> |
| <entry>0x01000000</entry> |
| <entry>Macrovision is an analog copy prevention system |
| mangling the video signal to confuse video recorders. When this |
| flag is set Macrovision has been detected.</entry> |
| </row> |
| <row> |
| <entry><constant>V4L2_IN_ST_NO_ACCESS</constant></entry> |
| <entry>0x02000000</entry> |
| <entry>Conditional access denied.</entry> |
| </row> |
| <row> |
| <entry><constant>V4L2_IN_ST_VTR</constant></entry> |
| <entry>0x04000000</entry> |
| <entry>VTR time constant. [?]</entry> |
| </row> |
| </tbody> |
| </tgroup> |
| </table> |
| |
| <!-- Capability flags based on video timings RFC by Muralidharan |
| Karicheri, titled RFC (v1.2): V4L - Support for video timings at the |
| input/output interface to linux-media@vger.kernel.org on 19 Oct 2009. |
| --> |
| <table frame="none" pgwide="1" id="input-capabilities"> |
| <title>Input capabilities</title> |
| <tgroup cols="3"> |
| &cs-def; |
| <tbody valign="top"> |
| <row> |
| <entry><constant>V4L2_IN_CAP_PRESETS</constant></entry> |
| <entry>0x00000001</entry> |
| <entry>This input supports setting DV presets by using VIDIOC_S_DV_PRESET.</entry> |
| </row> |
| <row> |
| <entry><constant>V4L2_IN_CAP_CUSTOM_TIMINGS</constant></entry> |
| <entry>0x00000002</entry> |
| <entry>This input supports setting video timings by using VIDIOC_S_DV_TIMINGS.</entry> |
| </row> |
| <row> |
| <entry><constant>V4L2_IN_CAP_STD</constant></entry> |
| <entry>0x00000004</entry> |
| <entry>This input supports setting the TV standard by using VIDIOC_S_STD.</entry> |
| </row> |
| </tbody> |
| </tgroup> |
| </table> |
| </refsect1> |
| |
| <refsect1> |
| &return-value; |
| |
| <variablelist> |
| <varlistentry> |
| <term><errorcode>EINVAL</errorcode></term> |
| <listitem> |
| <para>The &v4l2-input; <structfield>index</structfield> is |
| out of bounds.</para> |
| </listitem> |
| </varlistentry> |
| </variablelist> |
| </refsect1> |
| </refentry> |