soft-fn reproduces the behavior of the Chromebook keyboard's Search key in linux. It uses an evdev uinput device, such that it works in Xorg, Wayland, and virtual consoles.
When certain keys are pressed in combination with Search/🔍︎ (located where the caps lock is usually found) different events are produced. This is similar to how the fn key behaves on many laptops (no event is produced for the Search key itself). However, unlike fn, Search/🔍︎ functions like an ordinary accelerator key when used in combination with keys not defined below. Search/🔍︎ also generates an event when tapped.
Additionally, caps lock may be activated by alt + 🔍︎.
This emulates the behavior seen in ChromeOS while also allowing the Search/🔍︎ key to be used for user-defined shortcuts with the other keys.
Search/🔍︎ produces a KEY_LEFTMETA code when tapped or held in combination with a key not defined below. This is the code for the key variously known as super, command/⌘, or the "windows" key.
The codes below are defined in linux/input-event-codes.h
| Key | code | 🔍︎+key code |
|---|---|---|
| F1/⇦ | BACK |
F1 |
| F2/⇨ | FORWARD |
F2 |
| F3/⟳ | REFRESH |
F3 |
| F4/⇱︎ | DASHBOARD¹ |
F4 |
| F5/🍱 | SCALE² |
F5 |
| F6/🔅 | BRIGHTNESSDOWN |
F6 |
| F7/🔆 | BRIGHTNESSUP |
F7 |
| F8/🔇 | MUTE |
F8 |
| F9/🔉 | VOLUMEDOWN |
F9 |
| F10/🔊 | VOLUMEUP |
F10 |
| ⏻ | nothing³ | POWER |
| ⌫ | BACKSPACE |
DELETE |
| ← | LEFT |
HOME |
| → | RIGHT |
END |
| ↑ | UP |
PAGEUP |
| ↓ | DOWN |
PAGEDOWN |
¹ The KEY_FULL_SCREEN code is inconveniently located beyond the first byte and not well known to software.
² KEY_SCALE is the code Apple keyboards use for the "expose" key, which performs a similar function and (at least) Gnome understands it oob.
³ This is different from the ChromeOS behavior.
Note: The power key on traditional form-factor Chromebooks generates a redundant KEY_POWER event from a second dedicated device that will trigger a suspend regardless of soft-fn. To disable this device copy the included udev rules file to /etc/udev/rules.d/. Do not disable this device to retain the functionality of
the ⏻/power key next to the volume rocker on convertibles.
For AMD64 Debian/Ubuntu/Gallium/etc, get a .deb here.
To build a .deb, clone then dpkg-buildpackage -us -uc.
If you don't want a .deb, clone then make.
My public key is at metaquanta.com/deb_signing_key.gpg.
Tested in bullseye on CHELL, but should work on any intel Chromebook.
Thank you, @Francesco149 for stupidlayers, even though I've since refactored it away.