defaults: ucm2: Rework ALSA UCM profiles
This is a bigger overhaul of the profiles inspired by studying WM8962 datasheet and debugging issues with PulseAudio.
Aside of a general cleanup, it changes several things aimed to improve audio quality on both inputs and outputs.
The new profile:
- allows PulseAudio to use hardware volume control and makes sure that PGA gains are user-configurable
- makes sure Zero-Cross feature is enabled for all relevant input and output paths
- enables High-Pass Filters to protect the speakers from potential damage, get rid of DC offset and to improve input speech legibility
- minimizes the amount of gains used in various paths
- makes "Speaker" profile use both speakers, each with the same downmixed mono signal, which improves volume and frequency response
- uses HD Bass feature for improved lower frequency response of internal speakers
- uses only the bottom microphone by default and duplicates it into both stereo channels (and creates a new "stereo microphones" device, so users can still access both microphones when desired)
- duplicates analog microphone signal into both stereo channels
- enables High Performance modes for better signal to noise ratio
- uses Dynamic Range Control for input path to control signal level and attenuate background noise
- switches to wired microphone automatically after plugging in (requires linux!583 (merged))
In addition, this MR also:
- sets modem's input volume to 50% to avoid modem-side clipping
- enables voice legibility enhancement and noise suppression in PA's echo-cancel module
Edited by Sebastian Krzyszkowiak