Re: [PATCH] soundwire: fix initializing sysfs for same devices on different buses

[Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>]

> I think we keep circling on the differences between "Controller" and
> "link" (aka bus). A Controller can have one or more links. A system can
> have one or more controllers.
> 
> Intel platforms have one controller and 4 or more links.
> QCOM platforms have one or more controllers with one link each.
> 
> I am not sure how this IDA-generated bus_id helps deal with these two
> cases, since we can't really make any assumptions on how
> controllers/links will be started and probed.
> 
> What we are missing is a hierarchical controller/link definition, IOW a
> controller_id should be given to the master by a higher level instead of
> using an IDA.

Tentative patches to introduce a 'controller_id' that's not an IDA are
here: https://github.com/thesofproject/linux/pull/4616

Initial results are positive for Intel devices. it *should* work for
other devices but I can't test. If folks at Linaro/Qualcomm and AMD can
give it a try, that would be much appreciated.

Thanks.