Comment 6 for bug 659780

 Mario, just did some testing in order to verify everything. I
 completely removed pommed, so this deamon is not interfering anymore
 with gnome-power-manager.

 The results:
 * The module correctly detects the version of my macbook
 * Without the option use_gmux, the 16 levels are back again. This
 provides the user with a stable, working solution.
 * With use_gmux=1 (and debugging enabled), the brightness of the
 backlight is adjusted by increments or decrements of size 1, just as you
 expected. So from a technical point of view it is working, from a user
 point of view it is alas not workable ;-)

 On Thu, 28 Oct 2010 15:41:50 -0000, Mario Schwalbe
 <email address hidden> wrote:
> 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 direct
> subscriber
> of the bug.
>
> 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
>
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