hid-wiimote-plus

This is a modification of the built-in Linux kernel module for Nintendo Wii remotes. It's a drop-in replacement for the original module.

How is it different from the original Linux driver?

The original driver does not follow the Linux input conventions. This table shows how the inputs are handled differently:

Input	hid-wiimote (original)	hid-wiimote-plus	Why
Remote d-pad	Mapped to keyboard arrows.	Mapped to BTN_DPAD_* buttons.	It's a gamepad, not a keyboard.
Plus/minus buttons	Mapped to keyboard "next/prev" multimedia keys.	Mapped to BTN_START/BTN_SELECT.	The plus/minus buttons are used as start/select, sometimes it's even written on the button.
Sticks	Inverted Y axis.	Normal Y axis.	The Linux docs say negative Y means "up", positive Y means "down".
CC and CCPro	Face buttons are mapped to button names (A, B, X, Y).	Face buttons are mapped to directions (north, south, east, west).	The Linux docs say face buttons in a diamond layout should be mapped to the directions.
CCPro	Bogus analog TL/TR triggers.	Does not have analog TL/TR triggers.	A device should not report triggers it doesn't have.
Balance Board	The 4 pressure sensors are combined as a pair of 2-D axes.	The 4 pressure sensors are reported as 4 separated axes.	The pressure sensors do not represent position in any way, they shouldn't be reported as such.
Accelerometer	Does not report INPUT_PROP_ACCELEROMETER and uses the wrong axes (RX, RY, RZ).	Reports INPUT_PROP_ACCELEROMETER, and uses the correct axes (X, Y, Z).	For "accelerometer" inputs, the left axes are reserved for linear acceleration, the right axes are for angular acceleration.
Motion Plus	Does not report INPUT_PROP_ACCELEROMETER.	Reports INPUT_PROP_ACCELEROMETER.	Applications won't be fooled into thinking it's a positional input.
CC and CCPro	Has an option to emulate the left stick with the d-pad.	Does not have this option.	Emulating/remapping input does not belong to a device driver.

Battery charge reporting has been slightly improved.

Memory allocations are now managed by the device node; this ensures all memory is deallocated when the device disconnects.

Installation

You will need the kernel development headers in your system. Additionally, you will need the DKMS package; it allows for easy install and uninstall, and will automatically rebuild the module when the kernel is updated.

Use the command:

sudo make install

To uninstall, use:

sudo make uninstall

If you just want to test it, without installing it, use these commands instead (DKMS is not needed in this case):

make
sudo rmmod hid-wiimote # unload current hid-wiimote module
sudo insmod ./hid-wiimote.ko

Udev rules

The script 99-wiimote.rules is installed automatically to /etc/udev/rules.d. It forces most devices to have global read/write permissions (MODE="0666") and tags them to be game input devices (ENV{ID_INPUT_JOYSTICK}="1") with rules like this:

SUBSYSTEM=="input", ATTR{name}=="Nintendo Wii Remote", MODE="0666", ENV{ID_INPUT_JOYSTICK}="1"

To inhibit a particular device (that is, stop it from generating input events), a different rule is used:

SUBSYSTEM=="input", ATTR{name}=="Nintendo Wii Remote IR", ATTR{inhibited}="1"

This may be necessary for games that cannot handle accelerometer or gyro data correctly. Some games may also keep reading from all available devices even when they're not used, which increases power consumption.

By default, accelerometer, gyro and IR inputs are all inhibited. This will cause the least amount of headaches. Edit /etc/udev/rules.d/99-wiimote.rules if you want to enable one of these devices; changes to the udev rules will take effect next time the device is connected.

You can use the evemu-record command from the evemu package to test if a device is working as intended.