[Question] About Roland Rubix series, alsa-ucm-conf and snd_usb_audio

[sim590]

I want to understand what alsa_ucm-conf is about exactly regarding the support for specific devices. I'm thinking to buy a Roland Rubix series audio interface (either 22 or 24) and I'm wondering if both my XLR inputs are gonna appear in alsa/pulseaudio/pipewire as separate input lines. Does that require a potential change in snd_usb_audio kernel module or only a configuration file on this repository? I've looked at the configuration files on this repository and I have found a Roland directory, but nothing about the Rubix series explicitly.

Presently, I have a Focusrite Scarlett 2i2 fake clone (unfortunately) which I'm gonna return shortly because it's counterfeit. As of right now, I don't see the two separate outputs, but only the following input:

which takes audio from my first XLR input port. I guess that's the class compliant interface behaviour. Correct me if I'm wrong, I'm trying to learn about all of this.

So, I just wanna be sure that if I go and buy my Roland Rubix, that the device is actually gonna show up the two input lines, and if not that I will know what I will have to do to make it so. Is there gonna be a configuration file required in alsa-ucm-conf? Any potentiel change in snd_usb_audio kernel module? I'm a bit confused about the details regarding the support of the audio interface devices.

Thanks.

[sim590]

I just bought my Roland Rubix22 and I also only have one input device:

> pactl list short sources
    60	easyeffects_sink.monitor	PipeWire	float32le 2ch 48000Hz	RUNNING
    61	easyeffects_source	PipeWire	float32le 2ch 48000Hz	RUNNING
    64	alsa_input.usb-MACROSILICON_USB_Video-02.analog-stereo	PipeWire	s16le 2ch 48000Hz	SUSPENDED
    65	alsa_output.pci-0000_0c_00.4.analog-stereo.monitor	PipeWire	s32le 2ch 48000Hz	SUSPENDED
    66	alsa_input.pci-0000_0c_00.4.analog-stereo	PipeWire	s32le 2ch 48000Hz	SUSPENDED
    74	alsa_output.pci-0000_06_00.1.hdmi-stereo-extra2.monitor	PipeWire	s32le 2ch 48000Hz	SUSPENDED
    724	alsa_output.usb-Roland_Rubix22-00.analog-stereo.monitor	PipeWire	s32le 2ch 48000Hz	RUNNING
>>> 725	alsa_input.usb-Roland_Rubix22-00.analog-stereo	PipeWire	s32le 2ch 48000Hz	RUNNING

But I got two XLR ports on my audio interface as show in the following picture:

What am I missing?