Comment 98 for bug 277589

On Sun, Aug 02, 2009 at 04:49:27PM -0000, Alex wrote:
> According to the rules it should match the second udi (the
> backlight),and as the udi does not contain "linux.sysfs_path" then
> necessary attributes should be added. But on my (and most likely
> benste's) config it does not. May be there is a bug in the process of
> rules being applied? But if I change the last matching rule to

> <match key="linux.sysfs_path" exists="true">

> it works!

> Why do we need to check if "linux.sysfs_path" exists to apply the
> config? Can we check for "laptop_panel.access_method"=sony-nvidia, as we
> make this assingment in 10-sony-laptop-brightness.fdi?

In the case of the 10-laptop-panel-mgmt-policy.fdi file, this is
specifically because hal has a generic method for setting/getting brightness
when linux.sysfs_path is available (hald-addon-generic-backlight), and
scripts to do other things when it is not available. The nvidia backlights
expose *a* sysfs path, so we should not change this, but the path doesn't
work with the standard in-kernel methods.

This difference should (IMHO) be encapsulated in the sony-specific fdi file.

> I guess the rule should look like this (I am not an expert, but the
> complete beginner):

> <match key="laptop_panel.access_method" string="sony-nvidia">

Yes, that's consistent with the one I've just uploaded as a proposed
replacement. :)

Cheers,
--
Steve Langasek Give me a lever long enough and a Free OS
Debian Developer to set it on, and I can move the world.
Ubuntu Developer http://www.debian.org/
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