hdaudiobus(4) [netbsd man page]
HDAUDIO(4) BSD Kernel Interfaces Manual HDAUDIO(4) NAME
hdaudio -- High Definition Audio device driver SYNOPSIS
hdaudio* at pci? dev ? function ? hdafg* at hdaudiobus? audio* at audiobus? options HDAUDIO_DEBUG options HDAUDIO_AFG_DEBUG DESCRIPTION
The hdaudio device driver is expected to support any PCI device which is compliant to the High Definition Audio Specification 1.0. It is a replacement for azalia(4). It was written from scratch following the Intel HD Audio and Microsoft Universal Audio Architecture specifica- tions. The driver consists of two interlinked components, which reflects the hardware design. The hdaudio component interfaces with a PCI/PCIe bus and provides an hdaudiobus(4) onto which different function groups attach. Each function group (e.g. audio, vendor-specific modem) is exported as a separate child device of the hdaudio controller. Audio function groups (a.k.a. audio codec) are exported as hdafg(4) devices. Audio codecs are available from a number of manufacturers and are made up of a number of widgets (e.g. audio mixer, output pin, analog-to- digital converter). The way the widgets are interlinked varies significantly between implementations. The tree of widgets must be parsed and mapped to mixer(4) controls. As part of this process, loops in the inter-codec links must be detected and muted, bi-directional pins must be set up appropriately and the locations of pins determined. Unlike the azalia(4) driver (which tends to generate a large number of unclearly named mixer(4) controls), hdaudio works backwards by starting with a list of desired, consistent and compatible mixer(4) controls and configuring/discovering appropriate widget link routes to fit. By following the published mechanisms for common implementations of widget parsing, it is expected that nearly all High Definition Audio devices will be supported without requiring per-device quirks. SEE ALSO
audio(4), mixer(4), pci(4), hdaudioctl(8), http://www.intel.com/standards/hdaudio/ http://www.microsoft.com/whdc/device/audio/ HISTORY
The hdaudio device driver appeared in NetBSD 5.1. AUTHORS
The hdaudio driver was written by Jared McNeill <jmcneill@NetBSD.org> under contract by Precedence Technologies Ltd <http://www.precedence.co.uk/>. The UAA-compliant widget parser is derived from the FreeBSD snd_hda(4) driver. BUGS
The following items are not yet implemented: o Improve power management support when driver is idle o Add support for non-PCM output formats o Handle unsolicited RIRB messages o Modem function groups BSD
September 28, 2010 BSD
Check Out this Related Man Page
audiohd(7D) Devices audiohd(7D) NAME
audiohd - HD audio controller generic codec audio core support.. DESCRIPTION
The audiohd driver provides support for the generic codec chips which are compatible with the Intel High-Definition Audio Controller 1.0 specification. API
This interface is described in the mixer(7I) and audio(7I) manual pages. Driver Versions Applications that open /dev/audio may use the AUDIO_GETDEV ioctl(2) to determine which audio device is being used. The audiohd driver returns the string SUNW,audiohd in the name field of the audio_device structure. The version field contains a letter "a" and the config field contains the string onboard1. Platform Ver. Out H. Phone Spkr. In Mic. CD x86/64 w/MCP HD audio a Y Y Y Y Y Y Key to the above table: Ver. = Version. Out = Line Out. H. Phone = Head Phone. Spkr = Internal Speaker. In = Line In. Mic. = Microphone. CD = CD=ROM. The audiohd device provides support for the internal speaker, headphone, line out, line in, microphone and replicated front panel audio parts. The play.mod_ports and record.mod_ports fields of the audio_info structure (see audio(7I)) indicate which ports may be manipulated. Audio Mixer Mode This driver supports the mixer mode only. (Compat mode is not supported). Audio Data Formats The audiohd device supports 16-bit linear encodings in stereo. With the mixer enabled, a continuous range of sample rates from 5510 to 48000 Hz is supported. With the mixer disabled, only sample rate 48000 Hz is supported. Sample Granularity Because the audiohd device follows the Intel HD Audio specification, buffers of audio data are supplied by streams and the reported input and output sample counts vary at any given time from the actual sample count by no more than the size of the buffers the audiohd driver is transferring. As a rule, programs should not rely on the absolute accuracy of the play.samples and record.samples fields of the audio_info structure. Interrupt Rate The driver determines how often play and record interrupts should take place. For playing audio, this determines how often and how much audio is requested from the audio mixer. The impact of interrupts on recording is minimal. However, if a very small read buffer size is set, the record interrupt rate should be increased to prevent the buffer from overflowing. You can use the /kernel/drv/audiohd.conf file to tune the play and record interrupt rates. Audio Status Change Notification As described in the audio(7I) and mixer(7I) man pages, it is possible to request asynchronous notification of changes in the state of an audio device. ERRORS
audiohd errors are described in the audio(7I) man page. FILES
/dev/audio Symbolic link to the system's primary audio device. (Not necessarily an audiohd audio device). /dev/audioctl Control device for the primary audio device. /dev/sound/0 Represents the first audio device on the system. (Not necessarily an audiohd audio device). /dev/sound/0ctl Audio control for /dev/sound/0. /usr/share/audio/samples Audio sample files. /kernel/drv/audiohd.conf audiohd driver configuration file. ATTRIBUTES
See attributes(5) for a descriptions of the following attributes: +--------------------+--------------------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +--------------------+--------------------------------------+ |Architecture |PC-based system | +--------------------+--------------------------------------+ |Availability |SUNWaudd, SUNWauda | +--------------------+--------------------------------------+ |Stability level |Evolving | +--------------------+--------------------------------------+ SEE ALSO
mixerctl(1), sdtaudiocontrol(1), ioctl(2), attributes(5), audio(7I), mixer(7I), streamio(7I) Intel High-Definition Audio Specification 1.0. - Intel Corporation ALC880 Specification -- Realtek Inc. http://www.sun.com/io DIAGNOSTICS
In addition to being logged, the following messages may appear on the system console: init_state() play interrupt rate set too low The play interrupt rate in audiohd.conf is set too low. It has been reset to the rate specified in the message. Updateaudiohd.conf to a higher play interrupt rate. init_state() play interrupt rate set too high The play interrupt rate set in audio810.conf is set too high. It has been reset to the rate specified in the message. Updateau- diohd.conf to a lower play interrupt rate. init_state() record interrupt rate set too low The record interrupt rate inaudiohd.conf is set too low. It has been reset to the rate specified in the message. Update audio810.conf to a higher record interrupt rate. init_state() record interrupt rate set too high The record interrupt rate in audiohd.conf is set too high. It has been reset to the rate specified in the message. Updateaudiohd.conf to a lower record interrupt rate. SunOS 5.11 12 Sep 2008 audiohd(7D)