T480 (06cb:009a) - python3-validity runs, but open-fprintd finds no devices

[eduardo-pcmr]

Hello,

I'm having an issue with my ThinkPad T480 fingerprint reader (USB ID 06cb:009a) on Arch Linux.

The python-validity-git package fails to start with a Signature validation failed: 0x4f04 error.

After a lot of troubleshooting (including a cold boot and trying helper scripts), I was able to get the service running by manually building the stable python-validity package from the AUR.

Now, systemctl status python3-validity.service shows active (running) and the logs are clean.

However, fprintd-enroll still fails with list_devices failed:. The log for open-fprintd.service shows DEBUG:root:no devices. This happens even after restarting both python3-validity.service and open-fprintd.service in the correct order.

It seems the driver service is running correctly but fails to advertise the device to open-fprintd via D-Bus.

Log output for python3-validity.service:
[~]$ systemctl status python3-validity.service
● python3-validity.service - python-validity driver dbus service
Loaded: loaded (/usr/lib/systemd/system/python3-validity.service; enabled;>
Active: active (running) since Fri 2025-09-12 21:46:07 -03; 192ms ago
Invocation: 42e51b9086d54393a4d365942c6c2e93
Main PID: 2158 (python3)
Tasks: 2 (limit: 18879)
Memory: 20.6M (peak: 20.6M)
CPU: 173ms
CGroup: /system.slice/python3-validity.service
└─2158 python3 /usr/lib/python-validity/dbus-service --debug

set 12 21:46:07 t480 systemd[1]: python3-validity.service: Scheduled restart jo>
set 12 21:46:07 t480 systemd[1]: Started python-validity driver dbus service.
set 12 21:46:07 t480 python3[2158]: DEBUG:root:>cmd> 3e
[~]$

Log output for open-fprintd.service:
[~]$ systemctl status open-fprintd.service
● open-fprintd.service - Open FPrint Daemon
Loaded: loaded (/usr/lib/systemd/system/open-fprintd.service; static)
Active: active (running) since Fri 2025-09-12 21:38:16 -03; 9min ago
Invocation: 7ff94d949e60482e81ef8c3525dcc272
Main PID: 1653 (open-fprintd)
Tasks: 1 (limit: 18879)
Memory: 13.9M (peak: 14.2M)
CPU: 104ms
CGroup: /system.slice/open-fprintd.service
└─1653 /usr/bin/python3 /usr/lib/open-fprintd/open-fprintd --debug

set 12 21:38:15 t480 systemd[1]: Starting Open FPrint Daemon...
set 12 21:38:16 t480 systemd[1]: Started Open FPrint Daemon.
set 12 21:38:16 t480 open-fprintd[1653]: /usr/lib/open-fprintd/open-fprintd:25:>
set 12 21:38:16 t480 open-fprintd[1653]: GObject.MainLoop().run()
set 12 21:38:42 t480 open-fprintd[1653]: DEBUG:root:GetDefaultDevice
set 12 21:38:42 t480 open-fprintd[1653]: DEBUG:root:no devices
[~]$

Thank you for your work on this project.

[compicat]

i m experiencing same problem lately. is there any solution? device is same t480. It was working without flaw some days ago.

[newv-cell]

same problem, i guess there is no fix

[Jack2267]

#222 you can try with my solution,for me and for another guy it seems to have worked....