Synaptics 06cb:009a initialization fails with varying flash errors on Linux Mint 22.3 / ThinkPad X1 Carbon Gen 6 #292

Environment

Laptop: Lenovo ThinkPad X1 Carbon 6th Gen

OS: Linux Mint 22.3 Cinnamon (Ubuntu 24.04 Noble base)

Fingerprint reader: Synaptics Metallica MIS Touch, USB ID 06cb:009a

Python: 3.12.3

python3-validity: 0.15~ppa2

open-fprintd: 0.7~ppa2

fprintd-clients: 1.90.1-1ubuntu5

Package source: ppa:uunicorn/open-fprintd

Problem

The fingerprint reader is detected by lsusb, but python3-validity fails during initialization. Consequently, fprintd-list reports No devices found and enrollment fails.

Errors observed

Initially, the service failed during firmware information retrieval:

Exception: Signature validation failed: 044f

Attempting the documented factory-reset script returned:

Exception: Failed: ba36

After resetting fingerprint data through Lenovo BIOS, initialization failed in init_flash() → get_flash_info():

Exception: Failed: 3ab4

After a complete shutdown and restart, the same operation failed with:

Exception: Failed: 48c0

Troubleshooting performed

Confirmed the reader is detected over USB.

Installed python3-validity, open-fprintd, and fprintd-clients from the upstream PPA.

Ran validity-sensors-firmware, which extracted Lenovo firmware from nz3gf07w.exe.

Rebooted and performed a full shutdown/power-on cycle.

Attempted the documented factory reset, which failed with ba36.

Reset fingerprint data from Lenovo BIOS.

Tested moving usb.send_init() before init_flash() in init.py. This caused command 01 to time out with usb.core.USBTimeoutError: [Errno 110] Operation timed out.

Restored the original init.py and confirmed the original initialization sequence.

Disabled the failing service pending further diagnosis.

Question

Is this a known firmware/flash initialization issue with sensor 06cb:009a and python-validity 0.15? Is there a safe recovery procedure or a tested patch for this device?

I can provide full debug logs if helpful.