No BACKLIGHT for

[Bastien Nocera]

On Fri, 2010-04-30 at 16:40 +0100, Bastien Nocera wrote:
> On Wed, 2010-04-28 at 11:51 +0200, Kay Sievers wrote:
> > On Wed, Apr 28, 2010 at 11:38, Richard Hughes <hughsient at gmail.com> wrote:
> > > Sorry to open an old wound, but it looks like radeon won't be adding
> > > BACKLIGHT into the driver, ever.
> > >
> > > https://bugs.freedesktop.org/show_bug.cgi?id=27859
> > 
> > That surely all belongs into the X server below the randr interface.
> > The intel driver does use the kernel sysfs interface below the randr
> > interface too. There is no reason other drivers can not simply do the
> > same.
> 
> Which is broken if your system doesn't have a platform way of changing
> the LCD backlight.
> 
> On my Macbook Air, I cannot change the backlight without switching to
> UMS. In KMS, the intel driver tries to use the sysfs interface, and
> there's none.
> 
> In UMS, the driver will go bit-banging itself, and can change the
> backlight level that way.

Thanks to Christophe for pointing me to:

http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=history;f=drivers/video/backlight/mbp_nvidia_bl.c;h=1b5d3fe6bbbccd3093cfb2772d4ee9deae42bcea;hb=HEAD
(which also handles intel video cards despite the name...)
and
https://bugs.freedesktop.org/show_bug.cgi?id=27885