With Linux 4.1 You Can Play With The Chrome OS Lightbar
Via new sysfs entries, those running a Linux distribution on the Chromebook Pixel can now control the LED brightness and colors. The brightness, sequence, and colors can all be adjusted by just writing to some the new /sys/devices/virtual/chromeos/cros_ec/lightbar.
Those with a Chrome OS lightbar on their device can find out the details for playing with it via this patch message. This new support is coming via the Chrome update for Linux 4.1.
Other Chrome OS device changes for Linux 4.1 are trackpad improvements, exposing the Chrome OS embedded controller (EC) user-space device interface, and MFD driver improvements.
Those unfamiliar with the Chrome OS lightbar can see this video below: