[hal-info] Some thinkpad panels don't use laptop_panel.brightness_in_hardware

[Danny Kukawka]

On Freitag, 24. Oktober 2008, Matthew Garrett wrote:
> On Fri, Oct 24, 2008 at 11:17:28AM +0100, Matthew Garrett wrote:
> > On Fri, Oct 24, 2008 at 11:16:34AM +0200, Danny Kukawka wrote:
> > > Is there a way to find out (e.g. via sysfs) if the kernel handles the
> > > change?
> >
> > If there's an ACPI backlight and
> > /sys/module/video/parameters/brightness_switch_enabled is Y.
>
> Oh, to clarify - this'll be true for basically all hardware that has an
> ACPI video backlight control.

That makes it really hard to do the right thing, since this module parameter 
can change and since there is no udev event if this happens. 

It would be really useful if there would be a sysfs attribute under 
/sys/class/backlight/acpi_video0/ and an event if the module parameter get 
changed. Otherwise HAL can't tell reliable if it's handled in hardware.

Danny