Linux's display brightness / backlight interface will finally be overhauled.

CTOnews.com Sept. 18, at this week's Linux Plumbers conference, Red Hat developer Hans de Goede introduced the progress of his work, which will bring a fix to the pain point problem of the display brightness / backlight interface for Linux.

Hans mentioned the problem of Linux backlight interface as early as 2014. at present, it is impossible to map a backlit sysfs device to a monitor, a monitor needs to adapt to multiple backlit sysfs devices, root permission is required to control brightness, and the meaning of a value of 0 is not defined.

Since then, he has been working on resolving current limitations through / sys/ class / backlight user-space API and introducing a new and better designed API.

To solve the current problem, Hans plans to add new "display_brightness" and "display_brightness_max" attributes to the DRM connector object, and solves the problem of a value of 0. When display_brightness_max = = 0, it is defined as no support for controlling brightness.

Interested CTOnews.com partners can check out Hans's PDF on LPC 2022, as well as kernel patches that fix the problem.