Re: [alsa-devel] [PATCH 0/2] soundwire: fix Kconfig select/depend issues

[Pierre-Louis Bossart]

On 4/12/19 5:06 AM, Srinivas Kandagatla wrote:
> On 11/04/2019 20:28, Pierre-Louis Bossart wrote:
> > 0-day/Kbuild starts complaining about missed module dependencies and
> > compilation issues. Since codecs and soc drivers need to be compilable
> > independently, let's fix this using the following model:
> >
> > SOUNDWIRE_INTEL ---- select -----------
> > ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ |
> > ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ v
> > REGMAP_SOUNDWIRE --- select ---> SOUNDWIRE_BUS
>
> Last time when I looked at this, Kconfig symbols SOUNDWIRE_BUS and 
> SOUNDWIRE looked totally redundant and bit over done.
>
> Removing SOUNDWIRE_BUS Kconfig did clean it up and made it bit more 
> align with others

Good point, but no. This is intentional and follows the Kconfig pattern 
pattern described by Takashi at https://lkml.org/lkml/2017/11/17/47

yes, this SOUNDWIRE is overkill for now, but let's assume there is a 
second non-intel implementation (which I understand as very likely given 
all the threads on ARM64 support). In that case you'd really want a 
top-level selector option that has no actual compilation impact - not 
used in any Makefile or code - but enables the sub-options and let 
users/distros select the platforms they care about.

SOUNDWIRE_BUS is really the lowest-common denominator that will be used 
by all drivers at the end.

> regarding REGMAP_SOUNDWIRE, It should be selected by the codec/soundwire 
> slave drivers isn't it?

yes, that was the intent.
Thanks
-Pierre