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Diffstat (limited to 'Documentation/DocBook/media/v4l/dev-radio.xml')
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diff --git a/Documentation/DocBook/media/v4l/dev-radio.xml b/Documentation/DocBook/media/v4l/dev-radio.xml deleted file mode 100644 index 3e6ac73b36af..000000000000 --- a/Documentation/DocBook/media/v4l/dev-radio.xml +++ /dev/null @@ -1,49 +0,0 @@ - <title>Radio Interface</title> - - <para>This interface is intended for AM and FM (analog) radio -receivers and transmitters.</para> - - <para>Conventionally V4L2 radio devices are accessed through -character device special files named <filename>/dev/radio</filename> -and <filename>/dev/radio0</filename> to -<filename>/dev/radio63</filename> with major number 81 and minor -numbers 64 to 127.</para> - - <section> - <title>Querying Capabilities</title> - - <para>Devices supporting the radio interface set the -<constant>V4L2_CAP_RADIO</constant> and -<constant>V4L2_CAP_TUNER</constant> or -<constant>V4L2_CAP_MODULATOR</constant> flag in the -<structfield>capabilities</structfield> field of &v4l2-capability; -returned by the &VIDIOC-QUERYCAP; ioctl. Other combinations of -capability flags are reserved for future extensions.</para> - </section> - - <section> - <title>Supplemental Functions</title> - - <para>Radio devices can support <link -linkend="control">controls</link>, and must support the <link -linkend="tuner">tuner or modulator</link> ioctls.</para> - - <para>They do not support the video input or output, audio input -or output, video standard, cropping and scaling, compression and -streaming parameter, or overlay ioctls. All other ioctls and I/O -methods are reserved for future extensions.</para> - </section> - - <section> - <title>Programming</title> - - <para>Radio devices may have a couple audio controls (as discussed -in <xref linkend="control" />) such as a volume control, possibly custom -controls. Further all radio devices have one tuner or modulator (these are -discussed in <xref linkend="tuner" />) with index number zero to select -the radio frequency and to determine if a monaural or FM stereo -program is received/emitted. Drivers switch automatically between AM and FM -depending on the selected frequency. The &VIDIOC-G-TUNER; or -&VIDIOC-G-MODULATOR; ioctl -reports the supported frequency range.</para> - </section> |