Introduction to ASoC
From an architectural point of view, the ASoC subsystem elements and their relationship can be represented as follows:
Figure 5.1 – ASoC architecture
The preceding diagram summarizes the new ASoC architecture, in which the machine entity wraps both platform and codec entities.
In the ASoC implementation prior to kernel v4.18, there was strict separation between SoC audio codec devices (represented by struct snd_soc_codec these days) and SoC platform interfaces (represented by struct snd_soc_platform) and their respective digital audio interfaces. However, there was an increasing amount of similar code between codecs, platforms, and other components. This led to a new and generic approach, the concept of the component. All drivers have been moved over to this new generic component, platform code has been removed, and everything has been refactored so that nowadays, we only talk about struct snd_soc_component (which may refer to...
