Apple M1/M2 Keyboard Backlight Support Set For The Linux 6.4 Kernel

In addition to Linux 6.4 bringing some early work around the Apple M2 device support that isn't yet ready for end-users but begins laying the foundation for supporting the new MacBook Air, MacBook Pro, and Mac Mini, another set of Apple changes have now been submitted ahead of this next kernel cycle.

A second set of Apple Soc DeviceTree updates were submitted today for the upcoming Linux 6.4 merge window. Making this round notable is adding the PWM controllers and backlight nodes for M1 and M2 devices.

"A late addition to the tree, adding the PWM controllers and associated keyboard backlight nodes, since that driver and its bindings are now on the way to 6.4."

Queued via linux-pwm.git's for-next as of earlier this month is adding the "pwm-apple" Apple PWM controller driver. The Apple SoC PWM support is used for controlling the keyboard backlight and other functionality. Now that this PWM controller driver is being mainlined, today's pull request has the DeviceTree additions for it.

The PWM controller and keyboard backlight bindings are added for Apple M1 MacBooks to the T8103 configuration, Apple M1 Pro/Max MacBook Pro laptops with the T600x configuration, and the initial Apple M2 MacBook support with the T8112 DT.

For Asahi Linux users running their downstream kernel, this Apple keyboard backlight support has been available for a few months already while now at least will be found in the mainline Linux 6.4 kernel as the latest upstream improvement.