What: /sys/class/chromeos/<ec-device-name>/lightbar/brightness Date: August 2015 KernelVersion: 4.2 Description: Writing to this file adjusts the overall brightness of the lightbar, separate from any color intensity. The valid range is 0 (off) to 255 (maximum brightness). What: /sys/class/chromeos/<ec-device-name>/lightbar/interval_msec Date: August 2015 KernelVersion: 4.2 Description: The lightbar is controlled by an embedded controller (EC), which also manages the keyboard, battery charging, fans, and other system hardware. To prevent unprivileged users from interfering with the other EC functions, the rate at which the lightbar control files can be read or written is limited. Reading this file will return the number of milliseconds that must elapse between accessing any of the lightbar functions through this interface. Going faster will simply block until the necessary interval has lapsed. The interval applies uniformly to all accesses of any kind by any user. What: /sys/class/chromeos/<ec-device-name>/lightbar/led_rgb Date: August 2015 KernelVersion: 4.2 Description: This allows you to control each LED segment. If the lightbar is already running one of the automatic sequences, you probably won’t see anything change because your color setting will be almost immediately replaced. To get useful results, you should stop the lightbar sequence first. The values written to this file are sets of four integers, indicating LED, RED, GREEN, BLUE. The LED number is 0 to 3 to select a single segment, or 4 to set all four segments to the same value at once. The RED, GREEN, and BLUE numbers should be in the range 0 (off) to 255 (maximum). You can update more than one segment at a time by writing more than one set of four integers. What: /sys/class/chromeos/<ec-device-name>/lightbar/program Date: August 2015 KernelVersion: 4.2 Description: This allows you to upload and run custom lightbar sequences. What: /sys/class/chromeos/<ec-device-name>/lightbar/sequence Date: August 2015 KernelVersion: 4.2 Description: The Pixel lightbar has a number of built-in sequences that it displays under various conditions, such as at power on, shut down, or while running. Reading from this file displays the current sequence that the lightbar is displaying. Writing to this file allows you to change the sequence. What: /sys/class/chromeos/<ec-device-name>/lightbar/userspace_control Date: August 2015 KernelVersion: 4.2 Description: This allows you to take the control of the lightbar. This prevents the kernel from going through its normal sequences. What: /sys/class/chromeos/<ec-device-name>/lightbar/version Date: August 2015 KernelVersion: 4.2 Description: Show the information about the lightbar version.