Dear Stefan, Thanks for your time investigating this bug!
So, I added acpi_backlight=vendor string to the kernel cmdline and backlight controls DO work now contrary to what gets printed to dmesg: [ 461.856388] ACPI: Failed to switch the brightness [ 463.473236] ACPI: Failed to switch the brightness I see that /sys/platform/acer-wmi/backlight/acer-wmi/brightness is present and reflects the current state properly. I will try building the kernel with the patch you posted and see what happens. Regarding date: yes, it is a proper date, lshal - power_management.acpi.linux.version = '20090521' , so it is definitely an unitialized memory. Thanks again! -- Acer Aspire 5520 has backlight broken in Karmic Koala https://bugs.launchpad.net/bugs/428910 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
