USB-Audio: Motu M4: no duplex profile

[pisquaredover6]

I have compiled alsa-ucm-conf v1.2.7.2 with the patches 3a6acaa5090a0c5a0d29c8a4906b6a60378774e2 and ad1618cdd33f5c78ee1a0a9d3db362ffcb9f2596. With this, I have simplex audio, but no duplex profiles any more.

Is there any chance we can add a duplex profile, as it used to be the case before alsa-ucm-conf introduced the M4?

[perexg]

No idea what you mean with simplex and duplex in this context. Do you see the appropriate output (sinks) and input (sources) paths ?

[pisquaredover6]

Sorry for the bad wording. At the moment, there is an output profile and an input profile, but no 'duplex' profile where where output and input work simultaneously without needing a pro audio setup.

[perexg]

The currrent UCM config does not split input and output devices to different profiles. There should be one profile named "Analog Stereo Outputs + Inputs" and second "Direct /cardname/" profile. Please, attach, pactl list output.

[pisquaredover6]

Thank you for looking into the issue! I am using pipewire v1:0.3.58-1. This is the output of pactl list:
pactl_list.txt

[perexg]

The UCM is not used in your case. PW tries to do the legacy probe.

Do you see any error for the alsaucm -c hw:0 set _verb HiFi command ?

[pisquaredover6]

There is some error, but I guess it's not about the Motu M4 on hw:3. On hw:0 there is some internal soundcard, that I cut out from the pactl list output.

% alsaucm -c hw:0 set _verb HiFi
ALSA lib parser.c:244:(error_node) UCM is not supported for this HDA model (HDA Intel PCH at 0xb4430000 irq 181)
ALSA lib main.c:1541:(snd_use_case_mgr_open) error: failed to import hw:0 use case configuration -6
alsaucm: error failed to open sound card hw:0: No such device or address

[pisquaredover6]

For hw:3 I get:

alsaucm -c hw:3 set _verb HiFi
ALSA lib ucm_cond.c:155:(if_eval_regex_match) RegexMatch error (If.Condition.Regex)
ALSA lib main.c:1541:(snd_use_case_mgr_open) error: failed to import hw:3 use case configuration -22
alsaucm: error failed to open sound card hw:3: Invalid argument

[perexg]

Oops, there's a typo in ad1618c. Could you try the above fix bbacb3f ?

[pisquaredover6]

I tried it.
The error in alsaucm -c hw:3 set _verb HiFi is gone now, there is no output. But the output and input profile for the Motu M4 are also gone. Attaching output of pactl list.
pactl_list_2.txt

[perexg]

It's difficult to tell something without debug logs, but if you are using kernel 5.19.9+ then you are most likely hitting this bug:

https://bugzilla.kernel.org/show_bug.cgi?id=216500

PW deactivated this card completely for a reason.

[pisquaredover6]

You are right, I was using a 5.19.9 kernel. After downgrading to 5.19.8, I can see the 'Analog Stereo Outputs + Inputs' profile and it works.
Thank you for the debugging and patching, and for pointing me to the kernel bug. I will watch the kernel bug ticket and close this issue.