Some devices might have nonfunctional 'Pro Audio' sound. This patch adds a
new 'api.acp.disable-pro-audio' option to disable pro-audio profile entirely.
Including C headers inside of `extern "C"` breaks use from C++. Hoist
the includes of standard C headers above the block so we don't try
to mangle the stdlib.
I initially tried to scope this with a targeted change but it's too
hard to do correctly that way. This way, we avoid whack-a-mole.
Firefox is working around this in their e21461b7b8b39cc31ba53c47d4f6f310c673ff2f
commit.
Bug: https://bugzilla.mozilla.org/1953080
Don't use the api.alsa.soft-mixer option to disable the path selection
but make a new api.alsa.disable-mixer-path.
Disabling the path selection might leave cards unusable after suspend,
so a separate option is a better idea.
See #4311
We always probe the Pro Audio profile with the maximum number of
channels but this can lead to a more limited amount of sample rates.
Add an option to set the channels used when probing so that the other
samplerates become available.
Fixes#2990
libacp is a port and wrapper around the pulseaudio card profile code.
It uses a set of templates for construct a card profile and mixer port
settings. It also has support for UCM when available for the hardware.