[Q] Software control of LCD backlight?

[Alex Deucher]

On 8/10/07, Pat Kane <pekane52 at gmail.com> wrote:
> Is it possible to vary the intensity of the backlight on
> modern LCD panels (e.g. Dell 17'') from software
> such as the X server?

If you are talking about a laptop panel, yes.  if you are talking
about a DVI or VGA connected panel, no.  for laptop panels, most
vendor APCI implementations provide backlight control (it's also
standard in the newer ACPI versions).  Those methods can be used.
Alternatively, if your laptop has an intel chip there is an output
property that allows you to control the backlight via the xserver.
I've also added experimental support to the radeon driver in the
randr-1.2 branch, however, it's currently commented out as not all
OEMs use this method for backlight control.

Alex