⌨️💡 tp-auto-kbbl

ThinkPad Auto Keyboard Backlight

tp-auto-kbbl enables keyboard backlighting whenever you start typing. After typing ends (+ timeout), the backlight turns off automatically. It runs in the background on your Linux laptop and checks for keyboard events (default /dev/input/event3).

It should work on any ThinkPad (tested on a 470s) and probably other laptops as well. Let me know if it runs on your device.

To keep CPU/RAM usage low and portability high, I've used Rust for development. This is my first project with it, so if spot anything weird – or plain wrong – let me know! I'm thankful for any advice.

Warning

tp-auto-kbbl works similar to a keylogger (requires root to capture keyboard events system-wide). Always be sure to check the source code.

Usage

Usage: tp-auto-kbbl [options]

Options:
    -h, --help          prints this help message
    -v, --version       prints the version
    -n, --no-dim        don't dim before bg turns off
    -l, --lazy          don't check actual hw brightness state
    -d, --device        specify the device file
    -b, --brightness    target keyboard brightness (1-2)
    -t, --timeout       time before the bg light turns off

Installation

Download the latest release, or clone and build it yourself.

Copy the binary

sudo cp tp-auto-kbbl /usr/bin/

Try it out

tp-auto-kbbl

# You'll probably get an error like this
thread 'main' panicked at 'Permission denied (os error 13)', src/main.rs:44:74

# Once more as root
sudo tp-auto-kbbl

Input device ID: bus 0x11 vendor 0x1 product 0x1
Evdev version: 10001
Input device name: "AT Translated Set 2 keyboard"
Phys location: isa0060/serio0/input0
Setting brightness to 0

Your backlight should turn off immediately. Try if it turns on when you press any button. If not, check if the input device is correct, you may adjust it via the -d parameter.

Systemd service

# Copy the [unit file](https://raw.githubusercontent.com/saibotd/tp-auto-kbbl/master/tp-auto-kbbl.service)
sudo cp tp-auto-kbbl.service /etc/systemd/system/

# (optional) Check if the parameters are correct
sudo nano /etc/systemd/system/tp-auto-kbbl.service

# Reload daemons
sudo systemctl daemon-reload

# Start the service
sudo systemctl start tp-auto-kbbl

# Check if the service runs fine
sudo systemctl status tp-auto-kbbl

Mär 04 14:02:06 Huffer systemd[1]: Started Auto toggle keyboard back-lighting.
Mär 04 14:02:06 Huffer tp-auto-kbbl[343]: Input device ID: bus 0x11 vendor 0x1 p
Mär 04 14:02:06 Huffer tp-auto-kbbl[343]: Evdev version: 10001
Mär 04 14:02:06 Huffer tp-auto-kbbl[343]: Input device name: "AT Translated Set
Mär 04 14:02:06 Huffer tp-auto-kbbl[343]: Phys location: isa0060/serio0/input0
Mär 04 14:02:07 Huffer tp-auto-kbbl[343]: Setting brightness to 0
Mär 04 14:02:09 Huffer tp-auto-kbbl[343]: Setting brightness to 2
Mär 04 14:02:25 Huffer tp-auto-kbbl[343]: Setting brightness to 0

# Finally enable the service
sudo systemctl enable tp-auto-kbbl

Copyright © 2020 Tobias Duehr