USB ID: 27c6:55b4
Reported in: Lenovo IdeaPad Flex 5 16ABR8, Lenovo IdeaPad Flex 5 14ARE05
Source: devices/27c6:55b4/README.md

Goodix GF3268 (USB 27c6:55b4)

Status: Working (enroll + verify reliable) via a patched fork.

Goodix TLS fingerprint sensor, reported by libfprint as Goodix TLS Fingerprint Sensor 55X4. Confirmed firmware revisions include GF3268_RTSEC_APP_10042 and GF3268_RTSEC_APP_10056. Found in various laptops behind the Goodix 27c6 vendor ID.

What was broken

Upstream libfprint has no driver that accepts this device. The closest support is the goodixtls work for the 511 family, which does not recognise the 55b4 product ID or its firmware family, and its PSK/TLS handling does not match this sensor.

What the fix does

The fix is a patched goodixtls driver (branch linked in CREDITS). It:

Accepts the GF3268_RTSEC_APP_10056 firmware-family prefix so the device is recognised.
(Re)provisions the device PSK via a white-box PSK write so the host and sensor share a key.
Corrects the goodix_send_preset_psk_write wire framing.
Enables the PSK ciphers at SECLEVEL=0 in the goodix TLS server so the handshake completes.
Tunes the sigfm matcher thresholds for reliable enroll/verify on this sensor.

Build and install

Follow docs/BUILD.md for dependencies, install, PAM setup, package pinning and troubleshooting. The only sensor-specific part is which source to build:

git clone https://github.com/jedbillyb/libfprint.git   # see CREDITS
cd libfprint
git checkout goodix-55b4-fixes

Alternatively, apply the patch series in patches/ on top of the upstream base commit named in patches/README.md.

After installing, fprintd-list "$USER" should name Goodix TLS Fingerprint Sensor 55X4.

Arch / Omarchy notes

Arch currently exposes OpenCV 5 through opencv5.pc. If Meson fails with Dependency "opencv4" not found, change the sigfm dependency in libfprint/sigfm/meson.build for that build:

opencv = dependency('opencv5', required: true)

When packaging the patched library locally, the package must satisfy both the package and shared-library dependencies used by Arch's fprintd package:

provides=('libfprint=1.94.6' 'libfprint-2.so=2-64')
conflicts=('libfprint' 'libfprint-git')

Omarchy's stock fingerprint wizard explicitly installs the repository libfprint package. Pacman will then offer to remove the custom Goodix package, which returns this sensor to an unsupported driver. Install fprintd directly, then enroll and verify with the commands below instead of rerunning the stock wizard.

For Omarchy lock-screen integration, create its dedicated PAM service only after enrollment and verification succeed:

printf '%s\n' \
  '#%PAM-1.0' \
  'auth       required                    pam_fprintd.so' \
  'account    include                     system-local-login' |
  sudo tee /etc/pam.d/omarchy-lock-fingerprint >/dev/null

This service is used only for the fingerprint path; Omarchy keeps password unlock as a separate fallback.

Enroll

fprintd-enroll "$USER"    # press repeatedly, vary angle/edge/pressure
fprintd-verify "$USER"    # want: verify-match

This sensor is small and the matcher is sigfm-based, so enrollment quality matters more than usual: if verify fails at odd angles, delete the print (fprintd-delete "$USER") and re-enroll with deliberately varied finger positions.

Tested on

Lenovo IdeaPad Flex 5 16ABR8 (82XY) on Void Linux (libfprint 1.94.6, fprintd) - login, sudo, and screen-lock unlock all working.
Lenovo IdeaPad Flex 5 14ARE05 (81X2) on Omarchy / Arch Linux (firmware GF3268_RTSEC_APP_10042, libfprint 1.94.6, fprintd 1.94.5) - enrollment, verification, and Omarchy screen-lock unlock all working.