Fixing MacBook Air’s touchpad (versions 2011-2012) in Void Linux.
Add kernel module bcm5974 to kernel’s initramfs:
sudo dracut --force --add-drivers bcm5974
Update dracut configuration files to include this module when building initramfs:
$ sudo sh -c 'cat <<EOF >/etc/dracut.conf.d/touchpad.conf
add_drivers+="bcm5974"
EOF'