[alsa-devel] simplify simple-card

[Kuninori Morimoto]

Hi Mark, all

I want to create new sound card driver which supports DAPM.
But I can't use simple-card driver for this purpose because DT binding issue.
I guess, this new sound card can use/share simple-card functions.

OTOH, simple-card is not "simple" today :(

Basically, main purpose of simple-card / new sound card is binding CPU/Codec settings
to ALSA SoC framework. But we have many pattern for it.
From DT bindings point of view, we can/should use same DT bindings for same settings.

Now, simple-card is supporting
 - single CPU/Codec
 - multi  CPU/Codec
 - more feature...

My opinion is that complex code has un-understandable bug.
So, how about simplify simple-card, what do you think about this idea ?
We separate current simple-card to common parts, and, simple-card specific parts.
basically, common parts controls DT bindings and ALSA SoC settings.
sound card specific parts cares each own feature.

I don't know about naming, but these audio card can use same bindings via common functions.

 - common             : basic common functions
 - simple-audio-card  : existing driver, keep as-is for compatible reason
 - single-audio-card  : single CPU/Codec sound card. simplified from simple-audio-card
 - multi-audio-card   : multi  CPU/Codec sound card. simplified from simple-audio-card
 - fixrate-audio-card : new sound card
                        same as single-audio-card, but it needs sampling-rate-convert via DAPM, 
 - chain-audio-card   : DAPM card (?)
 - ....

My idea is taht we can replace current "simple-audio-card" to "single-audio-card",
or, "simple-audio-card" to "multi-audio-card" on DT.


Best regards
---
Kuninori Morimoto