F19 Macbook Air Brightness Issue after suspend
On a clean reboot, my brightness hotkeys and setting manually (e.g. su -c "echo 10 > /sys/class/backlight/intel_backlight/brightness") works fine. The brightness 'steps' increment smoothly from 0% to 100% brightness. However, after a suspend / restore, there are only two effective brightness steps - 0% or about 95%. Anything below 95% brightness and the screen turns off, and anything above that and it's about 95% brightness. The hotkeys still technically work and show the percentage correctly (and /sys/class/backlight/intel_backlight/brightness appears to show the correct value too), but the actual screen is either all on or all off.
mhicks@localhost ~$ cat /sys/class/backlight/intel_backlight/brightness
2639
mhicks@localhost ~$ cat /sys/class/backlight/intel_backlight/max_brightness
2777
I've tried setting acpi_backlight=vendor in my kernel command line which didn't work and I've tried the various rc.local scripts to set the brightness on boot and another script in /etc/pm/sleep.d/ to set the brightness on sleep but that didn't work as well.
Any ideas?
I've opened the following bug to hopefully move things along. Please comment if you experience the same issue: https://bugzilla.redhat.com/show_bug.cgi?id=989555