Alter Blue Blinking Light Behavior

Is there a way to alter the blue light so that it’s solid when the kernel is running instead of blinking? The blinking is a bit irritating, and intuitively an LED blinking in a fixed pattern usually indicates an error – at least that’s been my experience across a range of other types of devices.


Yes, the LEDs are controlled by GPIOs and are fully programmable to various events.

See /sys/class/leds. You can control the trigger and more.

I’m using raspbian. /sys/class/leds does not exist. Is there any documentation available for this?

Thank you.

What image are you using?

Raspbian 11 from libre:

Run sudo apt update && sudo apt dist-upgrade and reboot.

Edit: I forgot that I swapped SD cards and reinstalled the OS. Did not run the update the second time. I see the folder now. Is there any documentation I can refer to on how to use the various files in there? Thanks.

Edit:Edit: Ok, I see the trigger file, and it looks like brackets [] control which option is selected for light operation, but the file is locked and can’t be edited, even by root, also taking into account ownership and file mode, AND trying it with sudo. Not ideal. Is there another way to alter this other than loading up the SD card in another linux system to edit the file?

See the first two links of linux led trigger - Google Suche

Thank you for the links. While waiting for a response and doing a deep dive on the history of /sys I discovered on my own that the actual answer to my question is an astounding:

#echo none > /sys/class/leds/librecomputer:blue/trigger

Imagine my surprise when that immediately shut the dang blue light up.

For anyone else finding this topic later, you can using the above command change the blue light function to the following options:

none usb-gadget usb-host kbd-scrolllock kbd-numlock kbd-capslock kbd-kanalock kbd-shiftlock kbd-altgrlock kbd-ctrllock kbd-altlock kbd-shiftllock kbd-shiftrlock kbd-ctrlllock kbd-ctrlrlock timer disk-activity disk-read disk-write ide-disk mtd nand-disk heartbeat cpu cpu0 cpu1 cpu2 cpu3 activity default-on panic mmc0 mmc1 rc-feedback rfkill-any rfkill-none mdio_mux-0.e40908ff:08:link mdio_mux-0.e40908ff:08:100Mbps mdio_mux-0.e40908ff:08:10Mbps hidpp_battery_0-charging-or-full hidpp_battery_0-charging hidpp_battery_0-full hidpp_battery_0-charging-blink-full-solid

I settled on mmc1 to display SD card activity, like a typical HDD light.

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Thank you for this! One thing I’m seeing is after a reboot, the setting must revert itself after running the #echo none > /sys/class/leds/librecomputer:blue/trigger command. Is there a permanent way to set this?

Write an overlay for libretech-wiring-tool to change the default trigger and then merge it.