Re: no backlight on radeon after recent kernel "upgrade"s

From: James Simmons
Date: Thu Feb 22 2007 - 11:00:40 EST

> > Howerver, I *do* strongly wish for a way to combine various drivers into a
> > single backlight device, where radeon/intelfb takes care of some stuff,
> > ibm-acpi/asus-laptop/sony-laptop takes care of other stuff, etc. Also, a
> > standard naming for the builtin screen(s) would help, calling it "ibm",
> > "asus", "sony" is not good IMHO.
> I wasn't aware of this problem. If some devices need bits from both
> raedon/whatever and acpi, the current implementations are just plain
> wrong. Its not really a backlight class problem and more of an
> implementation and interaction problem between acpi and the framebuffer
> drivers. They should be presenting and registering *one* backlight class
> device, not two. Without knowing more about the circumstances and
> how/when to combine which drivers its hard for me to help further...

This is always been a problem. For the fbdev layer you can run vesafb with
a specific fbdev driver and they both access the same hardware. There is
no really way around this. The user has to be smart enough to not enable
bothe drivers.

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