Volume + / − buttons of Apple's wired 3.5 mm EarPods remote on Linux laptops.
The centre (play/pause) button already works almost everywhere: it simply shorts the mic line. The volume buttons don't. Apple's remote expects an identification exchange over the mic bias, which Apple's own codecs (Cirrus Logic CS42L83/84) do in hardware, and typical PC codecs such as Realtek's ALC2xx can't.
But even un-addressed, the remote disturbs the mic line on every volume press, and each button leaves its own repeatable ~10 ms signature:
applemote listens for those signatures on the headset mic and turns them into
ordinary KEY_VOLUMEUP / KEY_VOLUMEDOWN presses, about 35 ms after you press.
| Machine | Codec / driver | Status |
|---|---|---|
| Lenovo Yoga 7 2-in-1 14IML9 (83DJ) | Realtek ALC287, SOF sof-hda-dsp |
Works, templates included |
| Anything else with a jack-detected headset mic | any | Try it: applemote calibrate, then please report back |
Requirements: Linux with PipeWire (pw-record, pactl), amixer, Python ≥ 3.11
with NumPy and SciPy.
# Arch
sudo pacman -S --needed python-numpy python-scipy alsa-utils
# Debian / Ubuntu
sudo apt install python3-numpy python3-scipy alsa-utils pipewire-bin pulseaudio-utils
# Fedora
sudo dnf install python3-numpy python3-scipy alsa-utils pipewire-utils pulseaudio-utilsgit clone https://github.com/RyanTheTide/applemote
cd applemote
make install # ~/.local + a udev rule (asks for sudo)
applemote setup # finds your headset mic, writes ~/.config/applemote/config.ini
applemote calibrate # only if setup says there are no templates for your machine
systemctl --user enable --now applemoteIf setup warns that keys must go through /dev/uinput (common on desktops),
run make install-uinput too. Log out and back in once after either warning.
It runs as a user service and needs no attention. Useful commands:
journalctl --user -u applemote -f # one line per key, plus pause/resume
applemote run -v # foreground, with scores and near misses
applemote calibrate --save-wav rec.wav # re-calibrate (e.g. a different headset)- It listens to the headset mic only while a headset with a mic is plugged in and no other app is using that mic. Audio is analysed in memory and never stored or sent anywhere. GNOME and KDE show the microphone indicator while it listens; that is expected.
- It borrows the mic gain. Detection needs an unclipped signal, so while listening the headset-mic gain is set to 0 dB. As soon as another app (a call, a recorder) opens the headset mic, your own gain is restored and detection pauses until that app is done. Saved gains survive crashes and are restored on the next start.
- udev rule (
/etc/udev/rules.d/70-applemote.rules): lets your login session write key events into the sound card's jack input devices. Those devices can only emit the keys and switches they already have. - Power: the audio path stays awake while it listens.
See docs/porting.md for how to check whether your codec already sees the buttons, calibrate, read the results, and contribute templates. It also covers how this was worked out on the ALC287.
make uninstall- aurora-silicon/linux#9, Apple headset remote support for the CS42L83/CS42L84 on Apple Silicon. It shows how Apple's own codecs identify the remote and decode its volume pulses.
MIT