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Re: SOLVED: Re: entering sleep mode quietly/non-verbose

> > I can fix the manpage WRT on/off feature. ISTR that earlier models
> > (Powerbook G3?) had 32 backlight levels (can anyone confirm that?) so the
> > adjustment range isn't necessarily the same for all.
> All Powerbooks using a PMU version 12 (G3 Pismo and all G4) have only 16 (0..15)
> brightness levels. As I remember right the kernel driver will always report 15 as
> max brightness level.

In fact, even the earlier Powerbooks work with 16 levels only these days -
the 32 level stuff must have been way back when the G3 Powerbooks were new
The backlight level 'register' would permit 255 levels (which ones are
safe to use is a matter of some confusion, though). The 16 levels are just
a matter of convenience to keep the backlight_conv[] tables short. I'm
sure these tables could be replaced by 32 level tables, or we could do
without any tables (they look like simple linear relations to me). The
only benefit I can see is to allow a more fine-grained control to
applications - for the good old backlight buttons, 15 levels seems enough.
I'll change the manpage accordingly.

Re: backlight control: could you please read back the current backlight
from the kernel before setting a new level upon brightness button events?
The sudden jump in intensity (after some script modified the backlight
level) is somewhat surprising otherwise.


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