Linux 5.12 Hooks In LED Support To The TTY Layer

Written by Michael Larabel in Linux Kernel on 18 February 2021 at 01:27 PM EST. 1 Comment
There is an interesting change with the TTY/serial changes for the in-development Linux 5.12 kernel.

With Linux 5.12 there is TTY LED support with new code added to the TTY core code and the kernel's LED layer. What is LED support around TTYs for with the Linux kernel? It's about allowing possible triggers. With the TTY triggers support, it's possible to configure the LEDs so that the TTY statistics will be periodically checked and if changed will cause the LED to flash once... Basically to be able to create flashing arbitrary LEDs on TTY activity. It could lead to some interesting use-cases with hobbyists and more.

The TTY trigger can be controlled through the LEDs sysfs class on activity and does work with serial devices. Details on configuring the support via this patch message.

This LED TTY trigger support has been a long time coming across a number of rounds of patch review while now is ready for Linux 5.12. The full list of TTY/serial changes for Linux 5.12 can be found via this pull request.
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