[PATCH v2] topology: Add topology file for generic HDA DSP machine driver

[Pierre-Louis Bossart]

>>> This is a reference topology, and it was successfully validated on 
>>> few production laptops (including models on which DMIC capture was 
>>> not working).

The topology exposes a path that's not present in the hardware then?

>> Sorry, I don't understand what's missing in the cAVS driver?
>>
>> All you need is to select a different topology based on the number of 
>> DMICs detected.
> 
> 
> We have a mechanism to choose the PCM configuration of given topology 
> path via amixer control. That way we can include both 2ch and 4ch DMIC 
> configurations in one topology file and simply change DMIC pipeline 
> configuration on runtime.
> 
> Unfortunately this mechanism is not currently available on upstream.
> 
> As said before, this is a reference topology, if needed I can also 
> upload modified version with 4ch DMIC path.

I don't understand the concept of 'reference topology'. It's not like 
anyone is going to modify this file, which is seriously cryptic, so it's 
got to be a 'usable topology', turn-key really.

You would need three files, with no dmic, with 2 dmic with 4 dmic and a 
driver level code selection. Today the code loads the topology name 
coming from NHLT or dfw_sst.bin, you'd need a more elaborate logic to 
deal with the hardware variants and without requiring any fiddling, 
rename or edits of topology files.