Re: ASoC: cs42l43: SDCA reattach timeout on Dell XPS 14 Panther Lake; chip stuck across distros and kernels; worked initially; still working at hardware level

[Tobias Bachmann <tobac@mailbox.org>]

On Fri, May 08, 2026 at 5:21:44PM CEST, Charles Keepax wrote:
> On Fri, May 08, 2026 at 04:16:19PM +0100, Charles Keepax wrote:
> > On Fri, May 08, 2026 at 04:56:03PM +0200, Tobias Bachmann wrote:
> > > On Fri, May 08, 2026 at 10:41:10AM CEST, Charles Keepax wrote:
> > > 
> > > From what I can gather, the audio path doesn't appear to gate on
> > > _STA
> > > for this device:
> > > - soundwire sdw-master-0-0 still reports SDW Slave Addr
> > > 
> > >   3001fa424501
> > > 
> > > - ACPI still announces the SDCA functions: device:29 SmartMic,
> > > 
> > >   device:2a UAJ, device:2b HID
> > > 
> > > - sdca_class still binds and reaches "probe complete"
> > > - sdca_class sdw:0:0:01fa:4245:01: timed out waiting for
> > > 
> > >   device re-attach (5s after probe complete)
> > > 
> > > - No soundcard created
> > 
> > Hmm... yeah I think maybe your kernel is missing:
> > 
> > de67b4ea168f ("soundwire: slave: Don't register devices that are
> > disabled in ACPI")
> > 
> > I think that was only moved into Linus's tree after v7.0. If
> > possible you could pull that in and retest.
> 
> Although I am little worried more might be required looking
> more closely. But let me know if you can test how it gets on
> otherwise I will add it to my list to poke. I think last time I
> tested that it was for a device that didn't also have a bunch of
> SDCA stuff and some of that runs through a different path so
> little nervous that might need a gate too.

Fortunately not. Tested on 7.1.0-rc2 and the speakers work fine. Lovely 
stuff :)

This is probably a very unique solution to a unique problem. But I'd be 
happy to test patches etc if you can use this information to foolproof 
the architecture, which might help others.

Best wishes,
Tobias