Brightness is already implemented #33
Description
sudo bash -c 'echo 222222 > /sys/devices/platform/hp-wmi/rgb_zones/zone00' will make keyboard dim white.
sudo bash -c 'echo FFFFFF > /sys/devices/platform/hp-wmi/rgb_zones/zone00' will make keyboard white.
All you have to do to reduce brightness is make the hex color itself a bit darker.