ALSA Overview
=============

The Advanced Linux Sound Architecture (ALSA) is a collection of
software to handle sound hardware on Linux. It includes a range of
card specific kernel modules that implement the ALSA API for their
particular hardware, as well as a range of end user applications for
comfiguring and operating the sourd system.

The ALSA API is quite flexible. It deals with the ides of a sound
system as consisting of two perspectives: the audio streaming (input
and output) and the audio control settings. A configuration includes
both declarations of possibilies for both streaming and control as
well as selected particulars. This flexibility makes up a rather
complex thought structure even though any one host typically has a
simple, particular setup.

ALSA recognizes "cards", i.e. actual hardware sound card a well as
virtual software emulated sound cards.

https://wiki.st.com/stm32mpu/wiki/ALSA_overview

https://www.alsa-project.org/alsa-doc/alsa-lib/