Fingerprint sensors are usually attached to USB and do not need a kernel driver. To test it is best to install the fprint_demo
packages that usually installs the library libfprint
that does all the work. http://www.freedesktop.org/wiki/Software/fprint/libfprint/
Before installing a PAM module to use it as a password, fprint_demo
should proof that it works reliable.
The libfprint
source code comes with example programs that might not become installed with libfprint
but could be compiled separately. Those sample programs capture fingerprint and convert them to images and do simple verification tasks.