NVIDIA Prepares The Linux Kernel For Future Laptops With EC-Driven Backlights

Written by Michael Larabel in NVIDIA on 20 September 2021 at 07:17 AM EDT. 2 Comments
NVIDIA is contributing a new open-source driver to the upstream Linux kernel for dealing with upcoming laptops where the backlight controls are handled by the device's embedded controller (EC).

With Linux 5.16 later this year NVIDIA is ready with the "wmaa-backlight-wmi" driver for EC-based backlight controls for upcoming laptop/notebook computers.

This new driver is queued as part of the platform-drivers-x86 material in "for-next" ahead of Linux 5.16. The NVIDIA patch explains:
A number of upcoming notebook computer designs drive the internal display panel's backlight PWM through the Embedded Controller (EC). This EC-based backlight control can be plumbed through to an ACPI "WMAA" method interface, which in turn can be wrapped by WMI with the GUID handle 603E9613-EF25-4338-A3D0-C46177516DB7.

Add a new driver, aliased to the WMAA WMI GUID, to expose a sysfs backlight class driver to control backlight levels on systems with EC-driven backlights.

NVIDIA has been working on this ~200 lines of code WMAA Backlight driver for Linux since last year and is being maintained upstream by Daniel Dadap of the company.
Related News
About The Author
Michael Larabel

Michael Larabel is the principal author of Phoronix.com and founded the site in 2004 with a focus on enriching the Linux hardware experience. Michael has written more than 20,000 articles covering the state of Linux hardware support, Linux performance, graphics drivers, and other topics. Michael is also the lead developer of the Phoronix Test Suite, Phoromatic, and OpenBenchmarking.org automated benchmarking software. He can be followed via Twitter, LinkedIn, or contacted via MichaelLarabel.com.

Popular News This Week