Bug#479089: gnome-power-manager: Doesn't respect hal property brightness_in_hardware

[Sven Arvidsson]

On Fri, 2008-05-02 at 19:20 +0200, Tomaz Solc wrote:
> On EeePC when you press Fn-F4 hardware automatically sets brightness one
> step higher, but also emits an ACPI event. Hardware like this has HAL 
> property "laptop_panel.brightness_in_hardware" set to "True" to notify
> software like g-p-m that they shouldn't touch brightness settings on
> ACPI events.
> 
> However g-p-m doesn't respect this and will in some cases make changes
> to the brightness setting that contradict the firmware (there seemed to
> be some support for "brightness_in_hardware" in 2.15, but it was removed
> in later versions).
> 
> The specific problem I'm having is on Eee PC where pressing the
> brightness hotkeys will sometimes make g-p-m mess up the brightness
> setting (the "current_hw != brightness->priv->last_set_hw" check doesn't
> seem to work in all cases - maybe there's a race condition with the
> hardware). But I'm guessing this could also cause problems on other laptops.
> 
> I'm attaching a patch that fixes this problem for me. It basically
> reintroduces code that was removed since version 2.15.

Hi,

I have seen this too, on my Eee. 

I doubt upstream will want to reintroduce this code. The problem is that
the hot keys really should be using the input layer to handle the keys,
this way HAL can intercept them and inform g-p-m that the brightness
have changed. See
http://people.freedesktop.org/~hughsient/quirk/quirk-keymap-modules.html
for more information.

I noticed that the changes for the eee was merged upstream in 2.6.26,
but I don't know if asus-laptop have been converted to use input yet
(there have been several patches suggested).


The patch you suggested could of course be applied, but only if it
doesn't cause any trouble for hardware which already does this right.

-- 
Cheers,
Sven Arvidsson
http://www.whiz.se
PGP Key ID 760BDD22
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 189 bytes
Desc: This is a digitally signed message part
Url : http://lists.alioth.debian.org/pipermail/pkg-gnome-maintainers/attachments/20080502/94ed55bd/attachment-0001.pgp