Re: [alsa-devel] [RFC/RFT PATCH] ASoC: topology: Improve backwards compatibility with v4 topology files

From: Takashi Iwai
Date: Wed May 23 2018 - 10:05:29 EST

On Wed, 23 May 2018 16:49:35 +0200,
Guenter Roeck wrote:
> On Wed, May 23, 2018 at 6:56 AM Takashi Iwai <tiwai@xxxxxxx> wrote:
> >
> > >
> > > My point was a bit different: distributions like Gallium start without
> > > the relevant topology files and UCM settings, and we should have a
> > > reference to quickly enable audio without having to borrow and modify
> > > files from another distro. I faced this issue when I worked with the
> > > Gallium folks to enable audio on Rambi and Cyan Chromebooks and
> > > ended-up creating this reference myself.
> >
> > This sounds rather like a question how the upstream distributes the
> > stuff properly...
> >
> Not really, or not only. My problem, in particular, is that I want (need)
> to be able to run different kernel versions with the same distribution, and
> I want to be able to swap kernel versions without having to update the root
> file system. That doesn't work if I have to use v4 configuration files for
> v4.4 and older kernels, and v5 configuration files for v4.9 and later
> kernels (besides, as I mentioned, that the v5 configuration files I found
> were all incomplete). In my opinion, thre should be exactly one
> configuration file for a given device, and there should be no need for
> users (or distributions) to hunt for the correct version of the file.

No doubt about the kernel backward compatibility, it should be

It's another problem, though, that downstream takes some wild stuff
without properly upstreaming. A known story everywhere.