ubuntu-x-swat team mailing list archive

[rydberg <rydberg@xxxxxxxxxxx>]

Bryce, thank you for your reply. The issue behind the solution patch is
that when setting the xrandr BACKLIGHT_CONTROL property to 'kernel' to
use the sysfs interface to control the LCD backlight, the existing sysfs
backlight interface is not detected. The MacBookAir, as well as many
other macbooks, use the mbp_nvidia_bl kernel module, which produces the
sysfs interface /sys/class/backlight/mbp_backlight. The current intel
driver code seems to list an explicit set of possible names after
/sys/class/backlight/, and mbp_backlight is not one of them. Applying
the supplied patch fixes the problem. The Xorg log for the working code
reveals this line:

/var/log/Xorg.0.log:(II) intel(0): found backlight control method
/sys/class/backlight/mbp_backlight

When the patch is not present, it searches for the first name in the
list in src/i830_lvds.c (asus-latop), does not find it and outputs a
corresponding error message.

Output of lspci attached.

(Rant: Marking bugs as 'incomplete' by automacy is a good way of keeping
the desk clean ;-))

** Attachment added: "lspci.txt"
   http://launchpadlibrarian.net/30725090/lspci.txt

** Changed in: xserver-xorg-video-intel (Ubuntu)
       Status: Incomplete => New

-- 
kernel backlight control method missing for macbooks
https://bugs.launchpad.net/bugs/417770
You received this bug notification because you are a member of Ubuntu-X,
which is subscribed to xserver-xorg-video-intel in ubuntu.