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+<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
+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>
+
+<section id="audio_data_types">
+<title>Audio Data Types</title>
+<para>This section describes the structures, data types and defines used when talking to the
+audio device.
+</para>
+
+<section id="audio_stream_source_t">
+<title>audio_stream_source_t</title>
+<para>The audio stream source is set through the AUDIO_SELECT_SOURCE call and can take
+the following values, depending on whether we are replaying from an internal (demux) or
+external (user write) source.
+</para>
+<programlisting>
+ typedef enum {
+ AUDIO_SOURCE_DEMUX,
+ AUDIO_SOURCE_MEMORY
+ } audio_stream_source_t;
+</programlisting>
+<para>AUDIO_SOURCE_DEMUX selects the demultiplexer (fed either by the frontend or the
+DVR device) as the source of the video stream. If AUDIO_SOURCE_MEMORY
+is selected the stream comes from the application through the <emphasis role="tt">write()</emphasis> system
+call.
+</para>
+
+</section>
+<section id="audio_play_state_t">
+<title>audio_play_state_t</title>
+<para>The following values can be returned by the AUDIO_GET_STATUS call representing the
+state of audio playback.
+</para>
+<programlisting>
+ typedef enum {
+ AUDIO_STOPPED,
+ AUDIO_PLAYING,
+ AUDIO_PAUSED
+ } audio_play_state_t;
+</programlisting>
+
+</section>
+<section id="audio_channel_select_t">
+<title>audio_channel_select_t</title>
+<para>The audio channel selected via AUDIO_CHANNEL_SELECT is determined by the
+following values.
+</para>
+<programlisting>
+ typedef enum {
+ AUDIO_STEREO,
+ AUDIO_MONO_LEFT,
+ AUDIO_MONO_RIGHT,
+ } audio_channel_select_t;
+</programlisting>
+
+</section>
+<section id="struct_audio_status">
+<title>struct audio_status</title>
+<para>The AUDIO_GET_STATUS call returns the following structure informing about various
+states of the playback operation.
+</para>
+<programlisting>
+ typedef struct audio_status {
+ boolean AV_sync_state;
+ boolean mute_state;
+ audio_play_state_t play_state;
+ audio_stream_source_t stream_source;
+ audio_channel_select_t channel_select;
+ boolean bypass_mode;
+ } audio_status_t;
+</programlisting>
+
+</section>
+<section id="struct_audio_mixer">
+<title>struct audio_mixer</title>
+<para>The following structure is used by the AUDIO_SET_MIXER call to set the audio
+volume.
+</para>
+<programlisting>
+ typedef struct audio_mixer {
+ unsigned int volume_left;
+ unsigned int volume_right;
+ } audio_mixer_t;
+</programlisting>
+
+</section>
+<section id="audio_encodings">
+<title>audio encodings</title>
+<para>A call to AUDIO_GET_CAPABILITIES returns an unsigned integer with the following
+bits set according to the hardwares capabilities.
+</para>
+<programlisting>
+ #define AUDIO_CAP_DTS 1
+ #define AUDIO_CAP_LPCM 2
+ #define AUDIO_CAP_MP1 4
+ #define AUDIO_CAP_MP2 8
+ #define AUDIO_CAP_MP3 16
+ #define AUDIO_CAP_AAC 32
+ #define AUDIO_CAP_OGG 64
+ #define AUDIO_CAP_SDDS 128
+ #define AUDIO_CAP_AC3 256
+</programlisting>
+
+</section>
+<section id="struct_audio_karaoke">
+<title>struct audio_karaoke</title>
+<para>The ioctl AUDIO_SET_KARAOKE uses the following format:
+</para>
+<programlisting>
+ typedef
+ struct audio_karaoke{
+ int vocal1;
+ int vocal2;
+ int melody;
+ } audio_karaoke_t;
+</programlisting>
+<para>If Vocal1 or Vocal2 are non-zero, they get mixed into left and right t at 70% each. If both,
+Vocal1 and Vocal2 are non-zero, Vocal1 gets mixed into the left channel and Vocal2 into the
+right channel at 100% each. Ff Melody is non-zero, the melody channel gets mixed into left
+and right.
+</para>
+
+</section>
+<section id="audio_attributes">
+<title>audio attributes</title>
+<para>The following attributes can be set by a call to AUDIO_SET_ATTRIBUTES:
+</para>
+<programlisting>
+ typedef uint16_t audio_attributes_t;
+ /&#x22C6; bits: descr. &#x22C6;/
+ /&#x22C6; 15-13 audio coding mode (0=ac3, 2=mpeg1, 3=mpeg2ext, 4=LPCM, 6=DTS, &#x22C6;/
+ /&#x22C6; 12 multichannel extension &#x22C6;/
+ /&#x22C6; 11-10 audio type (0=not spec, 1=language included) &#x22C6;/
+ /&#x22C6; 9- 8 audio application mode (0=not spec, 1=karaoke, 2=surround) &#x22C6;/
+ /&#x22C6; 7- 6 Quantization / DRC (mpeg audio: 1=DRC exists)(lpcm: 0=16bit, &#x22C6;/
+ /&#x22C6; 5- 4 Sample frequency fs (0=48kHz, 1=96kHz) &#x22C6;/
+ /&#x22C6; 2- 0 number of audio channels (n+1 channels) &#x22C6;/
+</programlisting>
+ </section></section>
+<section id="audio_function_calls">
+<title>Audio Function Calls</title>
+
+
+<section id="audio_fopen">
+<title>open()</title>
+<para>DESCRIPTION
+</para>
+<informaltable><tgroup cols="1"><tbody><row><entry
+ align="char">
+<para>This system call opens a named audio device (e.g. /dev/dvb/adapter0/audio0)
+ for subsequent use. When an open() call has succeeded, the device will be ready
+ for use. The significance of blocking or non-blocking mode is described in the
+ documentation for functions where there is a difference. It does not affect the
+ semantics of the open() call itself. A device opened in blocking mode can later
+ be put into non-blocking mode (and vice versa) using the F_SETFL command
+ of the fcntl system call. This is a standard system call, documented in the Linux
+ manual page for fcntl. Only one user can open the Audio Device in O_RDWR
+ mode. All other attempts to open the device in this mode will fail, and an error
+ code will be returned. If the Audio Device is opened in O_RDONLY mode, the
+ only ioctl call that can be used is AUDIO_GET_STATUS. All other call will
+ return with an error code.</para>
+</entry>
+ </row></tbody></tgroup></informaltable>
+<para>SYNOPSIS
+</para>
+<informaltable><tgroup cols="1"><tbody><row><entry
+ align="char">
+<para>int open(const char &#x22C6;deviceName, int flags);</para>
+</entry>
+ </row></tbody></tgroup></informaltable>
+<para>PARAMETERS
+</para>
+<informaltable><tgroup cols="2"><tbody><row><entry
+ align="char">
+<para>const char
+ *deviceName</para>
+</entry><entry
+ align="char">
+<para>Name of specific audio device.</para>
+</entry>
+ </row><row><entry
+ align="char">
+<para>int flags</para>
+</entry><entry
+ align="char">
+<para>A bit-wise OR of the following flags:</para>
+</entry>
+ </row><row><entry
+ align="char">
+</entry><entry
+ align="char">
+<para>O_RDONLY read-only access</para>
+</entry>
+ </row><row><entry
+ align="char">
+</entry><entry
+ align="char">
+<para>O_RDWR read/write access</para>
+</entry>
+ </row><row><entry
+ align="char">
+</entry><entry
+ align="char">
+<para>O_NONBLOCK open in non-blocking mode</para>
+</entry>
+ </row><row><entry
+ align="char">
+</entry><entry
+ align="char">
+<para>(blocking mode is the default)</para>
+</entry>
+ </row></tbody></tgroup></informaltable>
+<para>ERRORS
+</para>
+<informaltable><tgroup cols="2"><tbody><row><entry
+ align="char">
+<para>ENODEV</para>
+</entry><entry
+ align="char">
+<para>Device driver not loaded/available.</para>
+</entry>
+ </row><row><entry
+ align="char">
+<para>EINTERNAL</para>
+</entry><entry
+ align="char">
+<para>Internal error.</para>
+</entry>
+ </row><row><entry
+ align="char">
+<para>EBUSY</para>
+</entry><entry
+ align="char">
+<para>Device or resource busy.</para>
+</entry>
+ </row><row><entry
+ align="char">
+<para>EINVAL</para>
+</entry><entry
+ align="char">
+<para>Invalid argument.</para>
+</entry>
+ </row></tbody></tgroup></informaltable>
+
+</section>
+<section id="audio_fclose">
+<title>close()</title>
+<para>DESCRIPTION
+</para>
+<informaltable><tgroup cols="1"><tbody><row><entry
+ align="char">
+<para>This system call closes a previously opened audio device.</para>
+</entry>
+ </row></tbody></tgroup></informaltable>
+<para>SYNOPSIS
+</para>
+<informaltable><tgroup cols="1"><tbody><row><entry
+ align="char">
+<para>int close(int fd);</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></tbody></tgroup></informaltable>
+<para>ERRORS
+</para>
+<informaltable><tgroup cols="2"><tbody><row><entry
+ align="char">
+<para>EBADF</para>
+</entry><entry
+ align="char">
+<para>fd is not a valid open file descriptor.</para>
+</entry>
+ </row></tbody></tgroup></informaltable>
+
+</section>
+<section id="audio_fwrite">
+<title>write()</title>
+<para>DESCRIPTION
+</para>
+<informaltable><tgroup cols="1"><tbody><row><entry
+ align="char">
+<para>This system call can only be used if AUDIO_SOURCE_MEMORY is selected
+ in the ioctl call AUDIO_SELECT_SOURCE. The data provided shall be in
+ PES format. If O_NONBLOCK is not specified the function will block until
+ buffer space is available. The amount of data to be transferred is implied by
+ count.</para>
+</entry>
+ </row></tbody></tgroup></informaltable>
+<para>SYNOPSIS
+</para>
+<informaltable><tgroup cols="1"><tbody><row><entry
+ align="char">
+<para>size_t write(int fd, const void &#x22C6;buf, size_t count);</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>void *buf</para>
+</entry><entry
+ align="char">
+<para>Pointer to the buffer containing the PES data.</para>
+</entry>
+ </row><row><entry
+ align="char">
+<para>size_t count</para>
+</entry><entry
+ align="char">
+<para>Size of buf.</para>
+</entry>
+ </row></tbody></tgroup></informaltable>
+<para>ERRORS
+</para>
+<informaltable><tgroup cols="2"><tbody><row><entry
+ align="char">
+<para>EPERM</para>
+</entry><entry
+ align="char">
+<para>Mode AUDIO_SOURCE_MEMORY not selected.</para>
+</entry>
+ </row><row><entry
+ align="char">
+<para>ENOMEM</para>
+</entry><entry
+ align="char">
+<para>Attempted to write more data than the internal buffer can
+ hold.</para>
+</entry>
+ </row><row><entry
+ align="char">
+<para>EBADF</para>
+</entry><entry
+ align="char">
+<para>fd is not a valid open file descriptor.</para>
+</entry>
+ </row></tbody></tgroup></informaltable>
+
+</section><section
+role="subsection"><title>AUDIO_STOP</title>
+<para>DESCRIPTION
+</para>
+<informaltable><tgroup cols="1"><tbody><row><entry
+ align="char">
+<para>This ioctl call asks the Audio Device to stop playing the current stream.</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_STOP);</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_STOP for this command.</para>
+</entry>
+ </row></tbody></tgroup></informaltable>
+<para>ERRORS
+</para>
+<informaltable><tgroup cols="2"><tbody><row><entry
+ align="char">
+<para>EBADF</para>
+</entry><entry
+ align="char">
+<para>fd is not a valid open file descriptor</para>
+</entry>
+ </row><row><entry
+ align="char">
+<para>EINTERNAL</para>
+</entry><entry
+ align="char">
+<para>Internal error.</para>
+</entry>
+ </row></tbody></tgroup></informaltable>
+
+</section><section
+role="subsection"><title>AUDIO_PLAY</title>
+<para>DESCRIPTION
+</para>
+<informaltable><tgroup cols="1"><tbody><row><entry
+ align="char">
+<para>This ioctl call asks the Audio Device to start playing an audio stream from the
+ selected source.</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_PLAY);</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_PLAY for this command.</para>
+</entry>
+ </row></tbody></tgroup></informaltable>
+<para>ERRORS
+</para>
+<informaltable><tgroup cols="2"><tbody><row><entry
+ align="char">
+<para>EBADF</para>
+</entry><entry
+ align="char">
+<para>fd is not a valid open file descriptor</para>
+</entry>
+ </row><row><entry
+ align="char">
+<para>EINTERNAL</para>
+</entry><entry
+ align="char">
+<para>Internal error.</para>
+</entry>
+ </row></tbody></tgroup></informaltable>
+
+</section><section
+role="subsection"><title>AUDIO_PAUSE</title>
+<para>DESCRIPTION
+</para>
+<informaltable><tgroup cols="1"><tbody><row><entry
+ align="char">
+<para>This ioctl call suspends the audio stream being played. Decoding and playing
+ are paused. It is then possible to restart again decoding and playing process of
+ the audio stream using AUDIO_CONTINUE command.</para>
+</entry>
+ </row><row><entry
+ align="char">
+<para>If AUDIO_SOURCE_MEMORY is selected in the ioctl call
+ AUDIO_SELECT_SOURCE, the DVB-subsystem will not decode (consume)
+ any more data until the ioctl call AUDIO_CONTINUE or AUDIO_PLAY is
+ performed.</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_PAUSE);</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_PAUSE for this command.</para>
+</entry>
+ </row></tbody></tgroup></informaltable>
+<para>ERRORS
+</para>
+<informaltable><tgroup cols="2"><tbody><row><entry
+ align="char">
+<para>EBADF</para>
+</entry><entry
+ align="char">
+<para>fd is not a valid open file descriptor.</para>
+</entry>
+ </row><row><entry
+ align="char">
+<para>EINTERNAL</para>
+</entry><entry
+ align="char">
+<para>Internal error.</para>
+</entry>
+ </row></tbody></tgroup></informaltable>
+
+</section><section
+role="subsection"><title>AUDIO_SELECT_SOURCE</title>
+<para>DESCRIPTION
+</para>
+<informaltable><tgroup cols="1"><tbody><row><entry
+ align="char">
+<para>This ioctl call informs the audio device which source shall be used
+ for the input data. The possible sources are demux or memory. If
+ AUDIO_SOURCE_MEMORY is selected, the data is fed to the Audio Device
+ through the write command.</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_SELECT_SOURCE,
+ audio_stream_source_t source);</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_SELECT_SOURCE for this command.</para>
+</entry>
+ </row><row><entry
+ align="char">
+<para>audio_stream_source_t
+ source</para>
+</entry><entry
+ align="char">
+<para>Indicates the source that shall be used for the Audio
+ stream.</para>
+</entry>
+ </row></tbody></tgroup></informaltable>
+<para>ERRORS
+</para>
+<informaltable><tgroup cols="2"><tbody><row><entry
+ align="char">
+<para>EBADF</para>
+</entry><entry
+ align="char">
+<para>fd is not a valid open file descriptor.</para>
+</entry>
+ </row><row><entry
+ align="char">
+<para>EINTERNAL</para>
+</entry><entry
+ align="char">
+<para>Internal error.</para>
+</entry>
+ </row><row><entry
+ align="char">
+<para>EINVAL</para>
+</entry><entry
+ align="char">
+<para>Illegal input parameter.</para>
+</entry>
+ </row></tbody></tgroup></informaltable>
+
+</section><section
+role="subsection"><title>AUDIO_SET_MUTE</title>
+<para>DESCRIPTION
+</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
+ played.</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_SET_MUTE,
+ boolean state);</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_SET_MUTE for this command.</para>
+</entry>
+ </row><row><entry
+ align="char">
+<para>boolean state</para>
+</entry><entry
+ align="char">
+<para>Indicates if audio device shall mute or not.</para>
+</entry>
+ </row><row><entry
+ align="char">
+</entry><entry
+ align="char">
+<para>TRUE Audio Mute</para>
+</entry>
+ </row><row><entry
+ align="char">
+</entry><entry
+ align="char">
+<para>FALSE Audio Un-mute</para>
+</entry>
+ </row></tbody></tgroup></informaltable>
+<para>ERRORS
+</para>
+<informaltable><tgroup cols="2"><tbody><row><entry
+ align="char">
+<para>EBADF</para>
+</entry><entry
+ align="char">
+<para>fd is not a valid open file descriptor.</para>
+</entry>
+ </row><row><entry
+ align="char">
+<para>EINTERNAL</para>
+</entry><entry
+ align="char">
+<para>Internal error.</para>
+</entry>
+ </row><row><entry
+ align="char">
+<para>EINVAL</para>
+</entry><entry
+ align="char">
+<para>Illegal input parameter.</para>
+</entry>
+ </row></tbody></tgroup></informaltable>
+
+</section><section
+role="subsection"><title>AUDIO_SET_AV_SYNC</title>
+<para>DESCRIPTION
+</para>
+<informaltable><tgroup cols="1"><tbody><row><entry
+ align="char">
+<para>This ioctl call asks the Audio Device to turn ON or OFF A/V synchronization.</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_SET_AV_SYNC,
+ boolean state);</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_AV_SYNC for this command.</para>
+</entry>
+ </row><row><entry
+ align="char">
+<para>boolean state</para>
+</entry><entry
+ align="char">
+<para>Tells the DVB subsystem if A/V synchronization shall be
+ ON or OFF.</para>
+</entry>
+ </row><row><entry
+ align="char">
+</entry><entry
+ align="char">
+<para>TRUE AV-sync ON</para>
+</entry>
+ </row><row><entry
+ align="char">
+</entry><entry
+ align="char">
+<para>FALSE AV-sync OFF</para>
+</entry>
+ </row></tbody></tgroup></informaltable>
+<para>ERRORS
+</para>
+<informaltable><tgroup cols="2"><tbody><row><entry
+ align="char">
+<para>EBADF</para>
+</entry><entry
+ align="char">
+<para>fd is not a valid open file descriptor.</para>
+</entry>
+ </row><row><entry
+ align="char">
+<para>EINTERNAL</para>
+</entry><entry
+ align="char">
+<para>Internal error.</para>
+</entry>
+ </row><row><entry
+ align="char">
+<para>EINVAL</para>
+</entry><entry
+ align="char">
+<para>Illegal input parameter.</para>
+</entry>
+ </row></tbody></tgroup></informaltable>
+
+</section><section
+role="subsection"><title>AUDIO_SET_BYPASS_MODE</title>
+<para>DESCRIPTION
+</para>
+<informaltable><tgroup cols="1"><tbody><row><entry
+ align="char">
+<para>This ioctl call asks the Audio Device to bypass the Audio decoder and forward
+ the stream without decoding. This mode shall be used if streams that can&#8217;t be
+ handled by the DVB system shall be decoded. Dolby DigitalTM streams are
+ automatically forwarded by the DVB subsystem if the hardware can handle it.</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_SET_BYPASS_MODE, boolean mode);</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_SET_BYPASS_MODE for this
+ command.</para>
+</entry>
+ </row><row><entry
+ align="char">
+<para>boolean mode</para>
+</entry><entry
+ align="char">
+<para>Enables or disables the decoding of the current Audio
+ stream in the DVB subsystem.</para>
+</entry>
+ </row><row><entry
+ align="char">
+</entry><entry
+ align="char">
+<para>TRUE Bypass is disabled</para>
+</entry>
+ </row><row><entry
+ align="char">
+</entry><entry
+ align="char">
+<para>FALSE Bypass is enabled</para>
+</entry>
+ </row></tbody></tgroup></informaltable>
+<para>ERRORS
+</para>
+<informaltable><tgroup cols="2"><tbody><row><entry
+ align="char">
+<para>EBADF</para>
+</entry><entry
+ align="char">
+<para>fd is not a valid open file descriptor.</para>
+</entry>
+ </row><row><entry
+ align="char">
+<para>EINTERNAL</para>
+</entry><entry
+ align="char">
+<para>Internal error.</para>
+</entry>
+ </row><row><entry
+ align="char">
+<para>EINVAL</para>
+</entry><entry
+ align="char">
+<para>Illegal input parameter.</para>
+</entry>
+ </row></tbody></tgroup></informaltable>
+
+</section><section
+role="subsection"><title>AUDIO_CHANNEL_SELECT</title>
+<para>DESCRIPTION
+</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>
+</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_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_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>
+<para>ERRORS
+</para>
+<informaltable><tgroup cols="2"><tbody><row><entry
+ align="char">
+<para>EBADF</para>
+</entry><entry
+ align="char">
+<para>fd is not a valid open file descriptor.</para>
+</entry>
+ </row><row><entry
+ align="char">
+<para>EINTERNAL</para>
+</entry><entry
+ align="char">
+<para>Internal error.</para>
+</entry>
+ </row><row><entry
+ align="char">
+<para>EINVAL</para>
+</entry><entry
+ align="char">
+<para>Illegal input parameter ch.</para>
+</entry>
+ </row></tbody></tgroup></informaltable>
+
+</section><section
+role="subsection"><title>AUDIO_GET_STATUS</title>
+<para>DESCRIPTION
+</para>
+<informaltable><tgroup cols="1"><tbody><row><entry
+ align="char">
+<para>This ioctl call asks the Audio Device to return the current state of the Audio
+ Device.</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_STATUS,
+ struct audio_status &#x22C6;status);</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_STATUS for this command.</para>
+</entry>
+ </row><row><entry
+ align="char">
+<para>struct audio_status
+ *status</para>
+</entry><entry
+ align="char">
+<para>Returns the current state of Audio Device.</para>
+</entry>
+ </row></tbody></tgroup></informaltable>
+<para>ERRORS
+</para>
+<informaltable><tgroup cols="2"><tbody><row><entry
+ align="char">
+<para>EBADF</para>
+</entry><entry
+ align="char">
+<para>fd is not a valid open file descriptor.</para>
+</entry>
+ </row><row><entry
+ align="char">
+<para>EINTERNAL</para>
+</entry><entry
+ align="char">
+<para>Internal error.</para>
+</entry>
+ </row><row><entry
+ align="char">
+<para>EFAULT</para>
+</entry><entry
+ align="char">
+<para>status points to invalid address.</para>
+</entry>
+ </row></tbody></tgroup></informaltable>
+
+</section><section
+role="subsection"><title>AUDIO_GET_CAPABILITIES</title>
+<para>DESCRIPTION
+</para>
+<informaltable><tgroup cols="1"><tbody><row><entry
+ align="char">
+<para>This ioctl call asks the Audio Device to tell us about the decoding capabilities
+ of the audio hardware.</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_CAPABILITIES, unsigned int &#x22C6;cap);</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_CAPABILITIES for this
+ command.</para>
+</entry>
+ </row><row><entry
+ align="char">
+<para>unsigned int *cap</para>
+</entry><entry
+ align="char">
+<para>Returns a bit array of supported sound formats.</para>
+</entry>
+ </row></tbody></tgroup></informaltable>
+<para>ERRORS
+</para>
+<informaltable><tgroup cols="2"><tbody><row><entry
+ align="char">
+<para>EBADF</para>
+</entry><entry
+ align="char">
+<para>fd is not a valid open file descriptor.</para>
+</entry>
+ </row><row><entry
+ align="char">
+<para>EINTERNAL</para>
+</entry><entry
+ align="char">
+<para>Internal error.</para>
+</entry>
+ </row><row><entry
+ align="char">
+<para>EFAULT</para>
+</entry><entry
+ align="char">
+<para>cap points to an invalid address.</para>
+</entry>
+ </row></tbody></tgroup></informaltable>
+
+</section><section
+role="subsection"><title>AUDIO_CLEAR_BUFFER</title>
+<para>DESCRIPTION
+</para>
+<informaltable><tgroup cols="1"><tbody><row><entry
+ align="char">
+<para>This ioctl call asks the Audio Device to clear all software and hardware buffers
+ of the audio decoder device.</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_CLEAR_BUFFER);</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_CLEAR_BUFFER for this command.</para>
+</entry>
+ </row></tbody></tgroup></informaltable>
+<para>ERRORS
+</para>
+<informaltable><tgroup cols="2"><tbody><row><entry
+ align="char">
+<para>EBADF</para>
+</entry><entry
+ align="char">
+<para>fd is not a valid open file descriptor.</para>
+</entry>
+ </row><row><entry
+ align="char">
+<para>EINTERNAL</para>
+</entry><entry
+ align="char">
+<para>Internal error.</para>
+</entry>
+ </row></tbody></tgroup></informaltable>
+
+</section><section
+role="subsection"><title>AUDIO_SET_ID</title>
+<para>DESCRIPTION
+</para>
+<informaltable><tgroup cols="1"><tbody><row><entry
+ align="char">
+<para>This ioctl selects which sub-stream is to be decoded if a program or system
+ stream is sent to the video device. If no audio stream type is set the id has to be
+ in [0xC0,0xDF] for MPEG sound, in [0x80,0x87] for AC3 and in [0xA0,0xA7]
+ for LPCM. More specifications may follow for other stream types. If the stream
+ type is set the id just specifies the substream id of the audio stream and only
+ the first 5 bits are recognized.</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_SET_ID, int
+ id);</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_SET_ID for this command.</para>
+</entry>
+ </row><row><entry
+ align="char">
+<para>int id</para>
+</entry><entry
+ align="char">
+<para>audio sub-stream id</para>
+</entry>
+ </row></tbody></tgroup></informaltable>
+<para>ERRORS
+</para>
+<informaltable><tgroup cols="2"><tbody><row><entry
+ align="char">
+<para>EBADF</para>
+</entry><entry
+ align="char">
+<para>fd is not a valid open file descriptor.</para>
+</entry>
+ </row><row><entry
+ align="char">
+<para>EINTERNAL</para>
+</entry><entry
+ align="char">
+<para>Internal error.</para>
+</entry>
+ </row><row><entry
+ align="char">
+<para>EINVAL</para>
+</entry><entry
+ align="char">
+<para>Invalid sub-stream id.</para>
+</entry>
+ </row></tbody></tgroup></informaltable>
+
+</section><section
+role="subsection"><title>AUDIO_SET_MIXER</title>
+<para>DESCRIPTION
+</para>
+<informaltable><tgroup cols="1"><tbody><row><entry
+ align="char">
+<para>This ioctl lets you adjust the mixer settings of the audio decoder.</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_SET_MIXER,
+ audio_mixer_t &#x22C6;mix);</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_SET_ID for this command.</para>
+</entry>
+ </row><row><entry
+ align="char">
+<para>audio_mixer_t *mix</para>
+</entry><entry
+ align="char">
+<para>mixer settings.</para>
+</entry>
+ </row></tbody></tgroup></informaltable>
+<para>ERRORS
+</para>
+<informaltable><tgroup cols="2"><tbody><row><entry
+ align="char">
+<para>EBADF</para>
+</entry><entry
+ align="char">
+<para>fd is not a valid open file descriptor.</para>
+</entry>
+ </row><row><entry
+ align="char">
+<para>EINTERNAL</para>
+</entry><entry
+ align="char">
+<para>Internal error.</para>
+</entry>
+ </row><row><entry
+ align="char">
+<para>EFAULT</para>
+</entry><entry
+ align="char">
+<para>mix points to an invalid address.</para>
+</entry>
+ </row></tbody></tgroup></informaltable>
+
+</section><section
+role="subsection"><title>AUDIO_SET_STREAMTYPE</title>
+<para>DESCRIPTION
+</para>
+<informaltable><tgroup cols="1"><tbody><row><entry
+ align="char">
+<para>This ioctl tells the driver which kind of audio stream to expect. This is useful
+ if the stream offers several audio sub-streams like LPCM and AC3.</para>
+</entry>
+ </row></tbody></tgroup></informaltable>
+<para>SYNOPSIS
+</para>
+<informaltable><tgroup cols="1"><tbody><row><entry
+ align="char">
+<para>int ioctl(fd, int request = AUDIO_SET_STREAMTYPE,
+ int type);</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_SET_STREAMTYPE for this
+ command.</para>
+</entry>
+ </row><row><entry
+ align="char">
+<para>int type</para>
+</entry><entry
+ align="char">
+<para>stream type</para>
+</entry>
+ </row></tbody></tgroup></informaltable>
+<para>ERRORS
+</para>
+<informaltable><tgroup cols="2"><tbody><row><entry
+ align="char">
+<para>EBADF</para>
+</entry><entry
+ align="char">
+<para>fd is not a valid open file descriptor</para>
+</entry>
+ </row><row><entry
+ align="char">
+<para>EINVAL</para>
+</entry><entry
+ align="char">
+<para>type is not a valid or supported stream type.</para>
+</entry>
+ </row></tbody></tgroup></informaltable>
+
+</section><section
+role="subsection"><title>AUDIO_SET_EXT_ID</title>
+<para>DESCRIPTION
+</para>
+<informaltable><tgroup cols="1"><tbody><row><entry
+ align="char">
+<para>This ioctl can be used to set the extension id for MPEG streams in DVD
+ playback. Only the first 3 bits are recognized.</para>
+</entry>
+ </row></tbody></tgroup></informaltable>
+<para>SYNOPSIS
+</para>
+<informaltable><tgroup cols="1"><tbody><row><entry
+ align="char">
+<para>int ioctl(fd, int request = AUDIO_SET_EXT_ID, int
+ id);</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_SET_EXT_ID for this command.</para>
+</entry>
+ </row><row><entry
+ align="char">
+<para>int id</para>
+</entry><entry
+ align="char">
+<para>audio sub_stream_id</para>
+</entry>
+ </row></tbody></tgroup></informaltable>
+<para>ERRORS
+</para>
+<informaltable><tgroup cols="2"><tbody><row><entry
+ align="char">
+<para>EBADF</para>
+</entry><entry
+ align="char">
+<para>fd is not a valid open file descriptor</para>
+</entry>
+ </row><row><entry
+ align="char">
+<para>EINVAL</para>
+</entry><entry
+ align="char">
+<para>id is not a valid id.</para>
+</entry>
+ </row></tbody></tgroup></informaltable>
+
+</section><section
+role="subsection"><title>AUDIO_SET_ATTRIBUTES</title>
+<para>DESCRIPTION
+</para>
+<informaltable><tgroup cols="1"><tbody><row><entry
+ align="char">
+<para>This ioctl is intended for DVD playback and allows you to set certain
+ information about the audio stream.</para>
+</entry>
+ </row></tbody></tgroup></informaltable>
+<para>SYNOPSIS
+</para>
+<informaltable><tgroup cols="1"><tbody><row><entry
+ align="char">
+<para>int ioctl(fd, int request = AUDIO_SET_ATTRIBUTES,
+ audio_attributes_t attr );</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_SET_ATTRIBUTES for this command.</para>
+</entry>
+ </row><row><entry
+ align="char">
+<para>audio_attributes_t
+ attr</para>
+</entry><entry
+ align="char">
+<para>audio attributes according to section ??</para>
+</entry>
+ </row></tbody></tgroup></informaltable>
+<para>ERRORS
+</para>
+<informaltable><tgroup cols="2"><tbody><row><entry
+ align="char">
+<para>EBADF</para>
+</entry><entry
+ align="char">
+<para>fd is not a valid open file descriptor</para>
+</entry>
+ </row><row><entry
+ align="char">
+<para>EINVAL</para>
+</entry><entry
+ align="char">
+<para>attr is not a valid or supported attribute setting.</para>
+</entry>
+ </row></tbody></tgroup></informaltable>
+
+</section><section
+role="subsection"><title>AUDIO_SET_KARAOKE</title>
+<para>DESCRIPTION
+</para>
+<informaltable><tgroup cols="1"><tbody><row><entry
+ align="char">
+<para>This ioctl allows one to set the mixer settings for a karaoke DVD.</para>
+</entry>
+ </row></tbody></tgroup></informaltable>
+<para>SYNOPSIS
+</para>
+<informaltable><tgroup cols="1"><tbody><row><entry
+ align="char">
+<para>int ioctl(fd, int request = AUDIO_SET_STREAMTYPE,
+ audio_karaoke_t &#x22C6;karaoke);</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_SET_STREAMTYPE for this
+ command.</para>
+</entry>
+ </row><row><entry
+ align="char">
+<para>audio_karaoke_t
+ *karaoke</para>
+</entry><entry
+ align="char">
+<para>karaoke settings according to section ??.</para>
+</entry>
+ </row></tbody></tgroup></informaltable>
+<para>ERRORS
+</para>
+<informaltable><tgroup cols="2"><tbody><row><entry
+ align="char">
+<para>EBADF</para>
+</entry><entry
+ align="char">
+<para>fd is not a valid open file descriptor</para>
+</entry>
+ </row><row><entry
+ align="char">
+<para>EINVAL</para>
+</entry><entry
+ align="char">
+<para>karaoke is not a valid or supported karaoke setting.</para>
+</entry>
+ </row></tbody></tgroup></informaltable>
+ </section>
+</section>