Open Sound System
OSS 4.x User's Guide

Do you have problems with sound/audio application development? Don't panic! Click here for help!

oss_hdaudio - Intel High Definition Audio (AZALIA)

Open Sound System driver for Intels high definition audio known as
"Azalia". This driver supports Intel 915/925 chipsets with the
Realtek ALC880 and CMedia 9880 8 channel codecs.

The HDA driver supports:

8-96Khz Playback/Recording
8 or 16 or 32 bits
2, 4, 6 or 8 channel audio.
SPDIF digital output and Input
AC3 passthrough

HDAUDIO MIXER

The Intel HDA mixer is a new type of mixer that doesn't have
the normal volume controls found on AC97 or legacy SB devices.
The HDA mixer presents a concept of Jacks and you can configure
any jack to be either an output or an input jack.

Some motherboards may not correctly initialize the jacks according
to their color and functionality but in general here's the
configuration that should generally be followed:

Orange = Center/LFE o Blue = Line-in
Black = Rear o Green = Front
Grey = Side o Pink = Mic

Some Azalia codecs support front panel connectors and so if you see
fp-green and fp-pink connectors, then these are for front panel
speaker and mic/line-in Jacks.

There is a function selector for most of the analog audio jacks (for example
connector.pink.mode). This selector is used to control if the jack is used
as an input (microphone or line in) or output (front, rear, side, speaker,
etc).

KNOWN PROBLEMS

In general Azalia based systems (laptops/motherboards) would require a custom driver to work properly. Due to enormous number of different systems it is not possible to develop such custom drivers for all systems. A generic driver is used for systems that don't have dedicated drivers.

Unfortunately the mixer and control panel interface (see ossmix ) for "generic" systems is very cryptic and difficult to understand. To solve problems with volumes or signal routing you need to start ossxmix and change the controls one at time until you get the desired effect.

OPTIONS

hdaudio_jacksense enables jack sensing mode when the hdaudio driver is loaded. In this mode all I/O pin's that are not
in use will be disabled as well as the mixer controls
that are related with them. In this way the
mixer/control panel will become more intuitive.
However OSS will need to be restarted with soundoff;
soundon every time new inputs or outputs are attached
to the audio jacks. Default : 0.

NOTE! hdaudio_jacksense=1 works only in some systems.
Many laptops and motherboards don't support jack
sensing.

hdaudio_noskip Disable skipping unconnected jack. All mixer controls will be shown, even for disabled I/O pins.
Can get values 0-7. 1-7 is a bitmask, where every bit
masks a different check. Bit 3 (= value 4) overrides
jacksense check too.
Default: 0 - unconnected jacks are skipped.

FILES

CONFIGFILEPATH/oss_hdaudio.conf Device configuration file

AUTHOR

4Front Technologies