USB ID: 2541:0236, 2541:9711
Reported in: GPD Win Max 2, AYANEO 2
Source: devices/2541:0236/README.md

Chipsailing CS9711 (USB 2541:0236, 2541:9711)

Status: Working via a maintained community fork (LGPL-2.1, no vendor blob).

Chipsailing "CS9711Fingprint" press sensor, 34x236 px. Sold as the built-in reader on several handhelds and mini PCs: GPD Win Max 2, AYANEO 2, GTR5 mini, and similar.

What was broken

Upstream libfprint has no cs9711 driver, so both product IDs are unrecognised and were on the libfprint wiki's unsupported list.

What the fix does

Adds a cs9711 image driver (press type, 15 enroll stages) that uses the sigfm matcher rather than NBIS, because the 34x236 captures are too small for minutiae extraction. Fully open, LGPL-2.1, no vendor blob.

Build and install

Maintained fork: archeYR/libfprint-CS9711 (LGPL-2.1). The original ddlsmurf repo is explicitly unmaintained and points here.

Arch (easiest): AUR package libfprint-cs9711-rebase-git.

yay -S libfprint-cs9711-rebase-git

Other distros: build the fork from source per docs/BUILD.md. The driver needs OpenCV for sigfm, so configure with sigfm enabled.

Tested on

Arch Linux via the AUR packages (libfprint-cs9711-git, libfprint-cs9711-rebase-git), on GPD Win Max 2 and AYANEO 2 class hardware.
Report your handheld and distro so this can be confirmed more widely.