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[media] DocBook: add missing AUDIO_* ioctls 

Add the missing AUDIO_* ioctls and document the V4L2 replacements for the
various DVB AUDIO ioctls that were (ab)used by V4L2.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
hifive-unleashed-5.1
Hans Verkuil 2012-08-09 05:46:16 -03:00 committed by Mauro Carvalho Chehab
parent 510f0a0ff0
commit a9d134f208
1 changed files with 112 additions and 1 deletions
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113
Documentation/DocBook/media/dvb/audio.xml
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@ -1,12 +1,16 @@
<title>DVB Audio Device</title>
<para>The DVB audio device controls the MPEG2 audio decoder of the DVB hardware. It
can be accessed through <emphasis role="tt">/dev/dvb/adapter0/audio0</emphasis>. Data types and and
ioctl definitions can be accessed by including <emphasis role="tt">linux/dvb/video.h</emphasis> in your
ioctl definitions can be accessed by including <emphasis role="tt">linux/dvb/audio.h</emphasis> in your
application.
</para>
<para>Please note that some DVB cards don&#8217;t have their own MPEG decoder, which results in
the omission of the audio and video device.
</para>
<para>
These ioctls were also used by V4L2 to control MPEG decoders implemented in V4L2. The use
of these ioctls for that purpose has been made obsolete and proper V4L2 ioctls or controls
have been created to replace that functionality.</para>
<section id="audio_data_types">
<title>Audio Data Types</title>
@ -558,6 +562,8 @@ role="subsection"><title>AUDIO_SELECT_SOURCE</title>
role="subsection"><title>AUDIO_SET_MUTE</title>
<para>DESCRIPTION
</para>
<para>This ioctl is for DVB devices only. To control a V4L2 decoder use the V4L2
&VIDIOC-DECODER-CMD; with the <constant>V4L2_DEC_CMD_START_MUTE_AUDIO</constant> flag instead.</para>
<informaltable><tgroup cols="1"><tbody><row><entry
align="char">
<para>This ioctl call asks the audio device to mute the stream that is currently being
@ -730,6 +736,8 @@ role="subsection"><title>AUDIO_SET_BYPASS_MODE</title>
role="subsection"><title>AUDIO_CHANNEL_SELECT</title>
<para>DESCRIPTION
</para>
<para>This ioctl is for DVB devices only. To control a V4L2 decoder use the V4L2
<constant>V4L2_CID_MPEG_AUDIO_DEC_PLAYBACK</constant> control instead.</para>
<informaltable><tgroup cols="1"><tbody><row><entry
align="char">
<para>This ioctl call asks the Audio Device to select the requested channel if possible.</para>
@ -772,6 +780,109 @@ role="subsection"><title>AUDIO_CHANNEL_SELECT</title>
</row></tbody></tgroup></informaltable>
&return-value-dvb;
</section><section id="AUDIO_BILINGUAL_CHANNEL_SELECT"
role="subsection"><title>AUDIO_BILINGUAL_CHANNEL_SELECT</title>
<para>DESCRIPTION
</para>
<para>This ioctl is obsolete. Do not use in new drivers. It has been replaced by
the V4L2 <constant>V4L2_CID_MPEG_AUDIO_DEC_MULTILINGUAL_PLAYBACK</constant> control
for MPEG decoders controlled through V4L2.</para>
<informaltable><tgroup cols="1"><tbody><row><entry
align="char">
<para>This ioctl call asks the Audio Device to select the requested channel for bilingual streams if possible.</para>
</entry>
</row></tbody></tgroup></informaltable>
<para>SYNOPSIS
</para>
<informaltable><tgroup cols="1"><tbody><row><entry
align="char">
<para>int ioctl(int fd, int request =
AUDIO_BILINGUAL_CHANNEL_SELECT, audio_channel_select_t);</para>
</entry>
</row></tbody></tgroup></informaltable>
<para>PARAMETERS
</para>
<informaltable><tgroup cols="2"><tbody><row><entry
align="char">
<para>int fd</para>
</entry><entry
align="char">
<para>File descriptor returned by a previous call to open().</para>
</entry>
</row><row><entry
align="char">
<para>int request</para>
</entry><entry
align="char">
<para>Equals AUDIO_BILINGUAL_CHANNEL_SELECT for this
command.</para>
</entry>
</row><row><entry
align="char">
<para>audio_channel_select_t
ch</para>
</entry><entry
align="char">
<para>Select the output format of the audio (mono left/right,
stereo).</para>
</entry>
</row>
</tbody></tgroup></informaltable>
&return-value-dvb;
</section><section id="AUDIO_GET_PTS"
role="subsection"><title>AUDIO_GET_PTS</title>
<para>DESCRIPTION
</para>
<para>This ioctl is obsolete. Do not use in new drivers. If you need this functionality,
then please contact the linux-media mailing list (&v4l-ml;).</para>
<informaltable><tgroup cols="1"><tbody><row><entry
align="char">
<para>This ioctl call asks the Audio Device to return the current PTS timestamp.</para>
</entry>
</row></tbody></tgroup></informaltable>
<para>SYNOPSIS
</para>
<informaltable><tgroup cols="1"><tbody><row><entry
align="char">
<para>int ioctl(int fd, int request =
AUDIO_GET_PTS, __u64 *pts);</para>
</entry>
</row></tbody></tgroup></informaltable>
<para>PARAMETERS
</para>
<informaltable><tgroup cols="2"><tbody><row><entry
align="char">
<para>int fd</para>
</entry><entry
align="char">
<para>File descriptor returned by a previous call to open().</para>
</entry>
</row><row><entry
align="char">
<para>int request</para>
</entry><entry
align="char">
<para>Equals AUDIO_GET_PTS for this
command.</para>
</entry>
</row><row><entry
align="char">
<para>__u64 *pts
</para>
</entry><entry
align="char">
<para>Returns the 33-bit timestamp as defined in ITU T-REC-H.222.0 / ISO/IEC 13818-1.
</para>
<para>
The PTS should belong to the currently played
frame if possible, but may also be a value close to it
like the PTS of the last decoded frame or the last PTS
extracted by the PES parser.</para>
</entry>
</row></tbody></tgroup></informaltable>
&return-value-dvb;
</section><section id="AUDIO_GET_STATUS"
role="subsection"><title>AUDIO_GET_STATUS</title>
<para>DESCRIPTION