[Intel-gfx] Legacy backlight control with KMS and BACKLIGHT property

[Greg KH]

On Fri, Aug 14, 2009 at 12:49:32PM -0700, Keith Packard wrote:
> On Fri, 2009-08-14 at 11:13 -0700, Greg KH wrote:
> 
> 
> > My question is, does this belong in the kernel side, to expose the
> > backlight through /sys/class/backlight/, or do we do this on the
> > userspace side in perhaps the xorg intel driver (where we can touch
> > pci config space just as easily)?
> 
> Also, /sys/class/backlight makes it hard to deal with machines that have
> two screens with different backlights, so we should at least hide this
> from user space for now and provide a suitable abstraction through KMS
> properties...

Why?  /sys/class/backlight should expose 2 backlights if they are known
and present, right?  Or is the problem that we don't expose new screens
in sysfs for userspace to be able to work out which is which?

If so, then that should be fixed as well :)

thanks,

greg k-h