In bugzilla gnome: https://bugzilla.gnome.org/show_bug.cgi?id=698271 > It looks like the graphics driver is broken... In bugzilla freedesktop intel: https://bugs.freedesktop.org/show_bug.cgi?id=63931 > It is not a bug in -intel or i915.ko, but in the acpi driver for your > backlight. Since kernel 3.5 or 3.6 max_backlight set from 15 to 100 and regulate failed. What is necessary information?
Hi Igor, From the linked page, it looks like manually poking /sys/class/backlight/acpi_video0 work well. Can you please confirm this? You can try the following command to see: # cd /sys/class/backlight/acpi_video # cat max_brightness should be 100 according to your report # echo 90 > brightness # cat brightness should return 90 now. you can test more levels.
(In reply to comment #1) > Hi Igor, > > From the linked page, it looks like manually poking > /sys/class/backlight/acpi_video0 work well. Can you please confirm this? You > can try the following command to see: > # cd /sys/class/backlight/acpi_video > # cat max_brightness > should be 100 according to your report > # echo 90 > brightness > # cat brightness > should return 90 now. > > you can test more levels. Yes If I change manually in sysfs node brightness change. # cat max_brightness 100 # echo 90 > brightness # cat brightness 90 And other value too
Created attachment 100031 [details] Test backlight
So this means gdbus call can not change backlight, while echo can. Is this correct?
(In reply to comment #4) > So this means gdbus call can not change backlight, while echo can. Is this > correct? Yes. You understand.
Then you will need to go back to gnome bugzilla page and telling them the fact. I don't know much about how gdbus works.
(In reply to comment #6) > Then you will need to go back to gnome bugzilla page and telling them the > fact. > I don't know much about how gdbus works. I wrote to the gnome BZ.
*** This bug has been marked as a duplicate of bug 51231 ***