Linux driver for the GunCon 2 light gun.

• A joystick device:
  • Reports absolute ABS_X and ABS_Y positions from the GunCon 2 sensor.
  • Reports trigger and other buttons as standard gamepad buttons (e.g. trigger as BTN_LEFT by default).
• A mouse device:
  • Provides relative motion and a standard mouse left-click, mapped from the same GunCon 2 trigger.

Emulators and frontends can use either:

• The joystick device (absolute aiming + buttons), or
• The mouse device (relative pointer + left click), depending on what works best.

The GunCon 2 must be calibrated for your display.

The joystick device’s ABS_X and ABS_Y ranges can be adjusted using evdev-joystick. This allows you to map the raw GunCon 2 coordinates to the visible area of your screen.

Example (adjust the values to your setup):

# X axis (joystick device)
evdev-joystick --e /dev/input/by-id/usb-0b9a_016a-event-joystick -m 175 -M 720 -a 0

# Y axis (joystick device)
evdev-joystick --e /dev/input/by-id/usb-0b9a_016a-event-joystick -m 20 -M 240 -a 1

It is also included a simple script for calibrating the GunCon 2, however the calibration must be performed each time the GunCon 2 is connected. This can be done with a set of udev rules.

For example;

SUBSYSTEM=="input", ATTRS{idVendor}=="0b9a", ATTRS{idProduct}=="016a", ACTION=="add", RUN+="/bin/bash -c 'evdev-joystick --e %E{DEVNAME} -m 175 -M 720 -a 0; evdev-joystick --e %E{DEVNAME} -m 20 -M 240 -a 1'"

./dkms_gcon2.sh all
./dkms_gcon2.sh remove

make modules
sudo make modules_install
sudo depmod -a
sudo modprobe guncon2

To reload after compiling you will first need to unload it using sudo modprobe -r guncon2.