Wireplumber (pipewire) causes ASoC DAI error message to repeat every login / logout

[KtheSurveyor]

I'm using Debian on an Alta, with kernel version 6.1.92, and I recently installed pipewire through APT to play audio on my system.

I haven't noticed any problems with actual playback, but I now have a two-line error message, related to the linux kernel ASoC DAI, that spams to the terminal and system log:

[ 113.155633] fe.dai-link-0: ASoC: no backend DAIs enabled for fe.dai-link-0
[ 113.156987] fe.dai-link-0: ASoC: error at dpcm_fe_dai_prepare on fe.dai-link-0: -22

This message repeats for link-0 several dozen times, then repeats again about 20 times for each of links 1-5. It specifically occurs on every login or logout of a user session.

By toggling various services through systemd, I narrowed one trigger down to the wireplumber service; with wireplumber disabled, no error message, though I suppose it could be merely starting a chain and the problem is elsewhere.

There are no other error messages before or after these ones that suggest a problem elsewhere. AFAICT the error message doesn't actually cause any problems with audio or system stability, but I figure it's still worth reporting, if only for code quality's sake.

It turns out there are scattered reports across various projects about this too, including on the Libre Computer Hub. They all seem to ignore the error message once they get audio playback working though.

[dsx724]

This has to do with audio routing in the default device-tree. We're not focused on the audio features at the moment but we will take a look at it later in the year.

[KtheSurveyor]

Sounds good. In the meantime, is there anything I can do to help make the changes easier? Any logs or tests you'd like me to run?

I can't really offer much of a time commitment, and I don't know the linux kernel well enough to submit patches. I've built instrumented kernels for debugging before though so if you want any preliminary help pinning down the issue, just let me know.

[dsx724]

The Linux kernel will print a lot of messages that are non-consequential. Developers have enough big bugs to squash so non-consequential error messages usually gets taken care of when something else pops up nearby and it gets re-done.

[KtheSurveyor]

Hi there, just want to give a quick update. With the recent LibreComputer kernel update (6.12.41-g2c40879474fe from Aug 5), the previous errors no longer repeat on login / logout.

Instead, there's now only a single error message of:

fe.dai-link-0: ASoC: no backend DAIs enabled for fe.dai-link-0, possibly missing ALSA mixer-based routing or UCM profile

So the log looks much more controlled now, even if the underlying sound config issue is still there. I haven't applied the second update from the past few days or re-flashed my firmware yet either.

[KtheSurveyor]

And after upgrading Debian to Trixie, the error message is actually gone now. Maybe the issue was already taken care of between kernels 6.1 and 6.12? Either way, I'll close this out as fixed now.

Thank you again for your help and enjoy the rest of your year.

[KtheSurveyor]

Actually, scratch that. No idea why it didn't show up while I was ironing out the Debian upgrade. Maybe I just didn't see it with the other log messages?

I just confirmed it's still there though with kernel version 6.12.41 and pipewire 1.4.2