defflag AUDIO_DEBUG

Include sequencer code conditionally. Fixes build for sparc and sparc64
(and anything else that has a midi but no sequencer).

Combine the midi and sequencer modules into a single midi_seq module
to avoid a circular dependency as noted in kern/56772. Retain minimal
modules of the original names to accomodate auto-loading upon access
to the /dev/xxx nodes.

defopt -> defparam (oops)

defopt AUDIO_BLK_MS

branches: 1.12.2; 1.12.4;
Merge isaki-audio2 branch, the overhaul of audio subsystem.
- Interrupt-oriented system rather than thread-oriented.
- Improve stability, quality and performance.
- Split playback and record cleanly. Improve halfduplex support.
- Many bugs are fixed including deadlocks, resource leaks, abuses, etc.
- Simplify audio filter mechanism. The encoding/channels/frequency
conversions are completely handled in the upper layer. So the hard-
ware driver only converts its hardware encoding (if necessary).
- audio_hw_if changes:
- Obsoletes query_encoding and add query_format instead.
- Obsoletes set_params and add set_format instead.
- Remove drain, setfd, mappage.
- The call sequences are changed.
- ioctl AUDIO_GETFD/SETFD, AUDIO_GETCHAN/SETCHAN are obsoleted.
- ioctl AUDIO_{QUERY,GET,SET}FORMAT are introduced.
- cleanup config attributes: au*conv and mulaw.
- All hardware drivers should follow it (I've done as much as possible).

Some file paths are changed:
- dev/audio.c -> dev/audio/audio.c (rewritten)
- dev/audiovar.h -> dev/audio/audiovar.h
- dev/audio_dai.h -> dev/audio/audio_dai.h
- dev/audio_if.h -> dev/audio/audio_if.h
- dev/audiobell.c -> dev/audio/audiobell.c
- dev/audiobellvar.h -> dev/audio/audiobellvar.h
- dev/mulaw.[ch] -> dev/audio/mulaw.[ch] + dev/audio/alaw.c

branches: 1.11.8; 1.11.12; 1.11.16;
Include auvolconv.o in the audio driver, even if there are currently no
children needing it. Children which need this can be created later (via
loading of a module, such as pad).

Add mulaw to audio device for auconv_set_converter.

This should address PR kern/51707.

name attachment after parent per existing convention.

Restructure speaker devices so that there can be multiple of them, and have
proper softc's.

one more vaudiospeaker remove

more spkr rework.

Add a synthesized pc beeper and keyboard bell for platforms with an audio
device.

The audio sub-system now supports the following features as
posted to tech-kern:

* Simultaneous playback and mixing of multiple streams
* Playback streams can be of different encoding, frequency, precision
and number of channels
* Simultaneous recording to different formats
* One audio device per process
* Sysctls to set the common format frequency, precision and channels
* Independent mixer controls for recording/playback per stream
* Utilizes little cpu time for multiple streams / good performance
* Compatible with existing programs that use OSS/NetBSD audio
* Changes to audioctl(1) to allow specifying process id for corresponding
audio device

branches: 1.3.2; 1.3.4;
Add common audio converters for software volume control. Only supports
slinear16_le and slinear16_be for now.

Convert pad(4) to use the new converters.

Normalize audio related definitions.

Move audio related definitions.