Update documents.
- query_format has been mandatory (since at least Feb 2020).
- set_params has been replaced to set_format (since May 2019).

Fix various typos, etc

Add a description to close().
> Before call to this, halt_input and halt_output are called if necessary.

Describe about (existing) constraints on round_blocksize().

Make start_input/halt_input optional if the driver has no recording,
make start_output/halt_output optional if the driver has no playback.
And remove such never called functions.

Remove superfluous Pp.

Describe about get_props() properties.

Bump date.

Improve wording, add more formatting.

Update manpages respond to isaki-audio2 branch.

Mark up NULL with Dv.

Two minor fixes.
- 0 -> NULL.
- avoid K&R and sync with reality.

Correct function name.
freem is used to free memory allocated by allocm.

Sync prototypes with reality. These have been changed in 2011.

branches: 1.47.2;
Move the audio specification to section 9 under audio_system.

Ok wiz@

Add the audio mixer specification to section 7 of the manual.
See posting on tech-kern - "NetBSD Audio Specification 2018."

branches: 1.45.4;
Remove workaround for ancient HTML generation code.

branches: 1.44.16;
Fix a typo in a function name. Found by Nat Sloss, thanks.
Fixes PR misc/46446.

branches: 1.43.6; 1.43.16;
update audio(9) docs for audiomp changes

branches: 1.42.22;
Convert TNF licenses to new 2 clause variant

Grammar fix.

branches: 1.40.6; 1.40.8;
Wups, bump date.

It's mixer_ctrl_t, not mixer_ctl_t.

branches: 1.38.2; 1.38.4;
kills a few `caddr_t' occurences still present in manpage

running in emulated wizd mode, convert caddr_t to void *.

s/.br/.Pp/; mark up AUDIOPOWER*; new sentence, new line.
Bump date for previous.

Document powerstate callback in audio_hw_if

Adapt man pages to ktrace-lwp.

Grammar improvement.

> -> \*[Gt]

Drop trailing whitespace.

Delete a superfluous comma.

Clarify that controls affecting both playback and recording should also
be placed in the AudioCinputs class.

reflect the recent audio_hw_if changes for open(), close(), set_params(),
round_blocksize(), trigger_output(), and trigger_input().
bump date.

Bump date for previous, and break lines
so that macros only affect what they should.

Fix a couple of long-standing bugs in the volume control(s) part of the
audio device interface:

1) When attempting to match the appropriate mixer control, we weren't
checking the class label, but only the second level label, so for
devices that had both an "inputs.cd" and a "record.cd", for example,
we could never do the right thing except by chance. For this reason,
evidently, all the record masters were labeled (by the underlying
drivers) either "record.record" or "record.volume", to distinguish
from "outputs.master". We'll now accept "record.master", and document
that as the the new preferred way.

2) More importantly, the model was deficient. Selecting a port on many
chips completely disables most of the level controls, which doesn't play
nice with other applications which are trying to use the interface. Now,
selecting a port simply sets which mixer input control shall be changed,
setting state in the audio layer. In other words, the "mixerout" port
is really selected all the time, enabling the final stage mixer, and
setting "gain" sets the level of the appropriate input. It should be
possible for separate applications to each control the mic, dac, and cd
inputs at the same time using this interface, simply by reiterating their
port selections with each change, but applications that don't bother to
do that aren't any worse off than they were before.

The user is expected to set the master output with another application,
dedicated to that task. Though it is now meaningful to select "no port"
with the audio device interface, to manipulate the master output, there's
no particular reason for an audio device consumer to do that. (I added
the capability in order to restore the initial state of the audio device,
for testing purposes. It might also be useful to users of broken binary-
only applications.)

Observe that the mixer device interface (and so, "mixerctl") still
retains all capabilities, including the ability to set the actual input
port on the chip, overriding the level controls. No change is being made
to the mixer device interface. The mixer device simply presents all the
controls on the chip, with no attempt at abstraction, so there are no
bugs there.

The upshot is, that applications that have been trying to use the audio
device interface to change the volume, such as mplayer, now "just work".

I've tested these changes extensively with "eso" and "eap" since first
proposing them on tech-kern last January, and somewhat with "esm" and a
few others. This closes both PR kern/10221, and PR kern/17159.

Bring audio(9) back in sync with audio_if.h; from Murray Armfield in
PR misc/21432.

Respect the law: Use A-law and mu-law as spellings as far as easily possible.
Inspired by Igor Sobrado in PR 19680.

New sentence, new line.

add factor_denom.

branches: 1.21.2;
Fix a typo

Update struct audio_params and description of set_params().
Feel free to correct my poor English ;-)

Fix pasto in type of dev_ioctl method.

Document a new method, dev_ioctl, for passing ioctl() down to the hardware
driver.

Fix typos, punctuation and whitespace.

Fix a couple of oversights.

Missed in previous: remove midi goo from argument list as well.

* Nuke obsoleted midi interface from audio_attach_mi().
* Document trgger_{in,out}put().
Fixes PR kern/9341.

allocm, freem: one step closer to reality.

Sync round_buffersize() with reality.

Make the copyrights conform to the standard.

branches: 1.10.2;
Remove blank lines.

More .Os cleanups. .Os is defined in the tmac.doc-common file,
so we shouldn't override it with versions in the manpages. Many more to
come.

Add David Brownlee's new intro pages, with editing. (PR #534[23])
Also, while here, expand apparently incorrectly .Dd month abbreviations.
(I thought about doing this in tmac/doc-common...heh...that would have
allowed a possible reverse map back to abbreviations.)

Layout changes.

Small clarification.

Update for SunOS compatibility.

Fix pastos.

Fix typos.

Fix tipo inherited from old version of TNF copyright form.
s/REGENTS/FOUNDATION/.

Initial version of the documentation of the interface between the
low and high level audio drivers, the audio_hw_if struct.