Yoga 920 fn-lock and conservation mode acpi platform driver. Actually it should be work on next models: Yoga 700, Yoga 710, Yoga 720, Yoga 900, Yoga 910, Yoga 920, but this information needs confirmation. Please NOTE: this code provided as is. You have to use it at your own risk.
While this module was tested on 4.15+ kernels(i guess it will also work with ealer versions of linux kernel), 4.18 kernel module ideapad_laptop supports fn_lock functionality out-of-box. So if you have 4.18+ kernel you do not need ideapad-hacks.
- Be sure actual kernel headers installed
- Clone repo, change directory and type make
- sudo insmod ideapad-hacks.ko
- sudo find /sys -name "fn_lock"
- In my case find says /sys/devices/pci0000:00/0000:00:1f.0/PNP0C09:00/VPC2004:00/fn_lock
- Check current fn_lock value: sudo cat /sys/devices/pci0000:00/0000:00:1f.0/PNP0C09:00/VPC2004:00/fn_lock
- Write new setting sudo echo 0 > /sys/devices/pci0000:00/0000:00:1f.0/PNP0C09:00/VPC2004:00/fn_lock
ideapad-hacks is not compatible with ideapad_laptop kernel module from linux kernel mainline. To use ideapad you MUST unload or blacklist ideapad_laptop. Ideapad-hacks is temporary solution and it will be deprecated as soon as fn_lock related patches will be reviewed and applyed by linux kernel mantainers.