Martin Matuska authored 11 years ago and Nick Schermer committed 11 years ago

The "Backlight" RandR property is a 32-bit integer. This means that the int32 (gint32) type should be used to represent brightness levels. The attached patch does nothing else than changing the brightness level representation from glong to gint32. This fixes the screen auto-dimming issue and brightness panel plugin issue.

installed by newer distros any more, so it's time to get rid of the HAL
brightness backend entirely, so drop it.

Since there are still X.org drivers which do not support brightness setting
through XRandR, add a xfpm-power-backlight-helper program which reads/writes
brightness setting in /sys/class/backlight/, and use it as a fallback if XRandR
brightness isn't available. Reading doesn't require any privileges, but for
writing the helper needs to be run as root through pkexec, so add a default
policy which allows running that without a password for the local foreground
console.

This was inspired from gnome-power-manager:

  http://git.gnome.org/browse/gnome-power-manager/commit/?id=4886023c

and the helper code comes from gpm, with slight adaptions.

Use gint instead of guint for the brightness level.

Brightness control now should be fully working, control of the lcd
backlight is done using xrandr by default but if this fails and if
HAL support is compiled then fallback, but still probably we need
to provide a key to force the power manager to use HAL when HAL
support is compiled because sometimes xrand reports that everything
is fine but it fails silently to change the brightness level, uhh
still too much suckiness in the backlight control on Linux.

a big part of xfpm and its configuration settings are broken.

In this branch polkit is a new optional dependency, this is for
getting if the user is permitted to use org.freedesktop.Devicekit.Power
sleep interfaces, also by default the power manager will try to
manipulate the lcd brightness using xrandr (doesn't work yet),
HAL remains an optional dependency of fall back for the lcd
brightness and in case of mapping failure of keyboard sleep keys.

If HAL support is compiled but HAL is not running
or stopped, xfpm should in future commits be able to handle this.