Digital microphone array (DMIC) not working on Huawei MateBook D14 2022 (Intel Alder Lake / Conexant SN6140)

Digital microphone array (DMIC) not working on Huawei MateBook D14 2022 (Intel Alder Lake / Conexant SN6140)

[GitHub issues - opened]

alsa-project/alsa-ucm-conf issue #857 was opened from lemonchik11:

Hello,

The built-in digital microphone array (DMIC) is completely silent and not capturing any audio on Huawei MateBook D14 2022 (Intel Alder Lake CPU). 

Hardware Details:
- Laptop: Huawei MateBook D14 2022
- Audio Codec: Conexant SN6140 (reported as SN6140 Analog under legacy HDA, subsystem ID 0x19e5:0x327e)
- OS: Arch Linux (Omarchy)
- Kernel: 7.2.3-arch1-3
- Sound Server: PipeWire / WirePlumber

What was tested:
1. Standard fallback 'snd-hda-intel' initializes the card in legacy analog mode. It creates a phantom "Internal Microphone" jack port but it stays completely dead (silence).
2. Forcing 'options snd-intel-dspcfg dsp_driver=3' to engage Sound Open Firmware (SOF) breaks the PCH bus entirely: the audio card completely disappears from the system, and the I2C-connected touchpad lock up (stops moving, only clicks respond). 
3. Manual pin retasking via 'hdajackretask' on Pin 0x19 (setting it to Internal Mic / Other Digital In) does not route the DMIC stream correctly.
4. The wired headset mic via 3.5mm jack works perfectly under standard legacy mode (dsp_driver=1), but the internal digital mic array remains completely inaccessible.

Here is my ALSA information link:
https://alsa-project.org/db/?f=2cc12e607be21d152c7f6e955013eff00dbbd432

Could you please assist in creating a correct UCM profile or kernel patch/quirk to map the digital microphone array for this Conexant SN6140 revision on Intel Alder Lake platforms? 

Thank you!

Issue URL     : https://github.com/alsa-project/alsa-ucm-conf/issues/857
Repository URL: https://github.com/alsa-project/alsa-ucm-conf