Jstest-gtk is a simple graphical joystick tester. it provides a list of attached joysticks, and for each one can display which buttons and axes are pressed, remap axes and buttons, and calibrate the device.

even when your joystick is working mostly fine, you might want to give it a try, as the calibration lets you get rid of overlarge default deadzones that many joysticks use and which are a noticeable problem in some games.

this package contains the debugging symbols.