Re: [PATCH 2/2] ASoC: Intel: Skylake: try to get NHLT blob with PCM params as fallback

[Cezary Rojewski]

On 2022-08-18 11:25 AM, Icenowy Zheng wrote:
> 在 2022-08-17星期三的 15:19 +0200，Cezary Rojewski写道：

...

> > NHLT was left alone across all the updates. Updating it is one way of
> > fixing problems but I don't believe it's necessary in your case.
> > Topology update is more desirable approach.
>
> BTW how could I fix the topology?
>
> I now use topology files from GalliumOS (which, I assume, is extracted
> from ChromeOS).

(save)

> > That clarifies things out. Guess the kernel version used there is
> > v4.4
> > (plus a ton of un-upstreamed patches). Again, will propagate the
> > information up the chain. Perhaps one of the solutions for end-users
> > would be providing working UCM files to alsa-topology-conf repo so
> > users
> > are not powerless in situations such as this one.

The message of mine above is the answer to this. Without some ADSP 
firmware knowledge it's almost impossible to write a topology file from 
scratch. During v4.4 -> v5.4 transition several problems with endpoints 
were detected as not all of them were behaving as expected. Long story 
short, I do not believe pure v4.4 on some of the designs (mainly I2S 
designs) works as intended. Some external patches are needed for that to 
happen.

The situation on v5.4 is much cleaner - the problem there are the 
topology files, as these are not updated automatically when you flash 
new kernel. In fact, these were never shared in alsa-topology-ucm repo. 
Only HDAudio topology has been fixed and shared. As long as you stick to 
the original ChromeOS the issues on your machine should cease to exist. 
I need some approvals before I2S designs can be shared. It's not a 
process that takes a day or two, unfortunately.


Regards,
Czarek