https://bugzilla.kernel.org/show_bug.cgi?id=214899 Bug ID: 214899 Summary: ideapad-laptop: platform backlight device not working Product: Drivers Version: 2.5 Kernel Version: 5.10.27-5.14.15 Hardware: All OS: Linux Tree: Mainline Status: NEW Severity: normal Priority: P1 Component: Platform_x86 Assignee: drivers_platform_x86@xxxxxxxxxxxxxxxxxxxx Reporter: johannes.penssel@xxxxxxxxx Regression: No Created attachment 299379 --> https://bugzilla.kernel.org/attachment.cgi?id=299379&action=edit DSDT.dsl Hardware: Lenovo IdeaPad 5 15ITL05, latest BIOS version Issue: Platform backlight device provided by ideapad-laptop has no effect on actual brightness. Pressing brightness keys on my keyboard causes changes in /sys/class/backlight/ideapad/actual_brightness, but no uevent is generated (as outlined in drivers/video/backlight.c source code comments), and /sys/class/backlight/ideapad/brightness is unaffected. When manipulating /sys/class/backlight/ideapad/brightness directly, uevents are being generated, but no change in real screen brightness occurs. The only way that screen brightness can actually be changed is by using i915's intel_backlight sysfs interface, which does not respond to brightness keyboard keys. attached is my decompiled DSDT and dmesg. ls -la /sys/class/backlight/ideapad/ total 0 drwxr-xr-x 3 root root 0 Oct 31 19:40 . drwxr-xr-x 3 root root 0 Oct 31 19:40 .. -r--r--r-- 1 root root 4096 Oct 31 19:40 actual_brightness -rw-r--r-- 1 root root 4096 Oct 31 19:40 bl_power -rw-rw-r-- 1 root video 4096 Oct 31 19:43 brightness lrwxrwxrwx 1 root root 0 Oct 31 19:40 device -> ../../../VPC2004:00 -r--r--r-- 1 root root 4096 Oct 31 19:40 max_brightness drwxr-xr-x 2 root root 0 Oct 31 19:40 power -r--r--r-- 1 root root 4096 Oct 31 19:40 scale lrwxrwxrwx 1 root root 0 Oct 31 19:40 subsystem -> ../../../../../../../class/backlight -r--r--r-- 1 root root 4096 Oct 31 19:40 type -rw-r--r-- 1 root root 4096 Oct 31 19:40 uevent -- You may reply to this email to add a comment. You are receiving this mail because: You are watching the assignee of the bug.
