mactel-support team mailing list archive

[Mario Schwalbe <schwalbe@xxxxxxxxxxxxxxxxx>]

Actually it is a bit different: Version 0.25 of mbp-nvidia-bl added (and enabled by default) a new approach of setting the backlight on MacBook Pro 6,1 and 6,2, that has been reported to work. Its new maximum is correctly 110400 (0x1af40). As of version 0.25.1, the old approach, supporting 16 levels (0-15) is the default again, while the new one can be enabled using the 
'use_gmux=1' driver option.

However, the problem seems to be pommed, which doesn't cope well with
large numbers of brightness levels, because 15 out of 110400 is
practically off and a step size of 1 is fairly too small. On the other
hand, pommed isn't required anymore as gnome-power-manager takes care of
display backlight (if the driver is loaded) appropriately. Can someone
test the new approach (use_gmux=1) without pommed running?

Using the old approach, pommed interferes as well. As you noticed, the
backlight gets adjusted with a step size of 2, because both pommed and
gnome-power-manager attempt to respond to the brightness keys. Hence, it
jumps 0-2-4-8-10-12-14-15 and 15-13-11-9-7-5-3-1-0 back (or 8 levels in
total). The same behaviour should be experienced using 0.24 and below,
because there are no differences.

I'll try to contact the maintainer to disable pommed's display backlight
in a default install.

-- 
mbp-nvidia-bl-dkms 0.25~lucid broken on MacBookPro6,2
https://bugs.launchpad.net/bugs/659780
You received this bug notification because you are a member of Mactel
Support, which is the registrant for Mactel Support.

Status in Mactel Support: New

Bug description:
After updating mbp-nvidia-bl-dkms 0.24.3~lucid to 0.25~lucid, backlight control is broken on MacBook Pro 6,2.
- Control keys to adjust brightness do not work anymore
- When unplugging the MacBook Pro from its power supply, the backlight is completely dimmed. Re-plugging the power supply restores the brightness to the value as it was before the laptop was unplugged.
- When the laptop is disconnected from its power supply and is booted, screen brightness is normal but not adjustable.

Running Ubuntu Lucid 64bit with generic kernel 2.6.32-25-generic.44
Using NVIDIA current drivers (195.36.24-0ubuntu1~lucid)
nvidia-bl-dkms is not installed as the backlight is steered by the Intel graphical adapter on the MacBook Pro 6,2