I tried _BCM for both its ACPI graphics devices, and it doesn't work whether "Enable Switchable Graphics" is enabled or not. So for this platform, the brightness is not controlled by its ACPI interface.
The nouveau backlight in use is nva3_bl_ops. Both its callback nva3_get_intensity() and nva3_set_intensity() correctly gets called by .get_brightness and .update_status, respectively. The proprietary Nvidia driver registered "nvidia_0" in backlight sysfs and it can adjust brightness correctly. Skimming through its kernel source, the backlight is set by rm_set_backlight() which resides in the binary blob. Seems like we need to reverse engineer this to make it work under nouveau. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1821882 Title: Screen is very dark and brightness cannot be adjusted To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1821882/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
