### System details

Lenovo ThinkPad X1 Carbon Gen 14 - 21V7CTO1WW

### What's wrong?

## Summary

On Lenovo ThinkPad X1 Carbon Gen 14, the integrated microphone delivers only silence (all-zero samples) under Omarchy. SOF detects the Cirrus Logic CS42L45 codec on SoundWire link 2 and CS35L56 speaker codec on link 3, but no SoundWire machine driver matches this combination on Panther Lake, so SOF falls back to a generic "default machine driver with function topologies" which does not produce real capture data.

This is a companion issue to #6000 (camera). Both Gen 14 problems trace to Panther Lake support gaps that don't affect Dell XPS PTL because XPS uses a different codec set (CS42L43, which has full topology coverage).

## Hardware / system

- Machine: Lenovo ThinkPad X1 Carbon Gen 14 (`21V7CTO1WW`)
- CPU: Intel Core Ultra X7 368H (Panther Lake)
- Audio: Intel SOF `sof-audio-pci-intel-ptl` (`PCI 8086:e428`)
- SoundWire codecs detected:
  - link 2: `mfg_id 0x01fa part_id 0x3563` — **Cirrus Logic CS42L45** (mic/headset)
  - link 3: `mfg_id 0x01fa part_id 0x4245` — **Cirrus Logic CS35L56** (speaker amp)
- Omarchy: 3.8.2
- Kernel: tested `linux 7.0.9-arch2-1` and `linux-ptl 7.0.9-arch1-1-ptl`
- `sof-firmware 2025.12.2-1`, `alsa-ucm-conf 1.2.15.3-1`

## Symptoms

Card identifies correctly:
```
$ cat /proc/asound/cards
 0 [sofsoundwire   ]: sof-soundw
                      LENOVO-21V
```

PipeWire exposes `sof-soundwire e, mapped to `hw:sofsoundwire,4`.
 Both PipeWire and direct ALSA c S16_LE -r 48000 -c 2`) read
successfully but return only zering the raw capture file:

```
$ od -An -vtu1 /tmp/mic-hw4.raw wc -l
1                    # all bytes
```

## Root cause (from kernel log)

```
sof-audio-pci-intel-ptl 0000:00:iver found for the ACPI-reported
configuration:
sof-audio-pci-intel-ptl 0000:00:part_id 0x3563 version 0x3
sof-audio-pci-intel-ptl 0000:00:part_id 0x4245 version 0x3
sof-audio-pci-intel-ptl 0000:00:achine driver with function
topologies
sof-audio-pci-intel-ptl 0000:00:ction topologies
```

The fallback path doesn't wire trectly. Looking at
`/usr/lib/firmware/intel/sof-ipc

- `sof-ptl-cs42l43-*` topologies
- `sof-ptl-dmic-*` topologies ex
- **No `sof-ptl-cs42l45-*` topolfirmware tree
- `alsa-ucm-conf` does ship a `c can't help without a matching
kernel machine driver + tplg

Existing upstream report:
[thesofproject/linux#5770](httpsinux/issues/5770) — "No
microphone capture on ThinkPad X) — cs42l45 PDE 11 event failed:
-110, missing sof-ptl-cs42l45 to

## What I've tried

- Switched between `linux` and `ms.
- Verified codecs are detected o
- Captured directly from `hw:0,4Jack In) — both return all-zero
samples.
- Confirmed PipeWire routing is iFi__Mic__source` →
`hw:sofsoundwire,4`).

## Suggested fix

This is fundamentally an upstrea35L56 + Panther Lake machine
driver + matching topology). Unt

1. Track [thesofproject/linux#57project/linux/issues/5770) andpull a patched `sof-firmware` on is published.
2. Add the machine driver patch patch exists.

Happy to test patches on this hardware and help out to make sure Omarchy works on this laptop!