Sensible trackball mappings for Kensington Slimblade Trackball in Wayland

90-kensington-slimblade-remap.hwdb

# Source: https://askubuntu.com/questions/1145057/remapping-mouse-buttons-to-keyboard-keys

# Scan codes and bus/vendor/product IDs are prefilled for the slimblade.

# Keycodes in HEX - convert to DEC for our config
# https://github.com/torvalds/linux/blob/master/include/uapi/linux/input-event-codes.h#L360

#define BTN_MOUSE        0x110  /* 272 */
#define BTN_LEFT         0x110  /* 272 */
#define BTN_RIGHT        0x111  /* 273 */
#define BTN_MIDDLE       0x112  /* 274 */
#define BTN_SIDE         0x113  /* 275 */ <- back
#define BTN_EXTRA        0x114  /* 276 */ <- forward
#define BTN_FORWARD      0x115  /* 277 */
#define BTN_BACK         0x116  /* 278 */
#define BTN_TASK         0x117  /* 279 */

# Scan codes
# 90003 90004
#     BALL
# 90001 90002

# Using the below will give you

#    [BACK]        [FWD]
#            BALL
# [LEFT CLICK]  [RIGHT CLICK]

# Format is SCAN_CODE=KEY_CODE_IN_DEC

evdev:input:b0003v047Dp2041*
 ID_INPUT_KEY=1
 KEYBOARD_KEY_90001=272
 KEYBOARD_KEY_90002=273
 KEYBOARD_KEY_90003=275
 KEYBOARD_KEY_90004=276
 
# Depending on app support, you might need to switch back to 278 and fwd to 277.

# evdev:input:b0003v047Dp2041*
#  ID_INPUT_KEY=1
#  KEYBOARD_KEY_90001=272
#  KEYBOARD_KEY_90002=273
#  KEYBOARD_KEY_90003=278
#  KEYBOARD_KEY_90004=277

Drop file in /etc/udev/hwdb.d and run:

sudo systemd-hwdb update && sudo udevadm control --reload-rules && sudo udevadm trigger