Re: Power Management framework proposal

[david@lang.hm]

On Fri, 27 Jul 2007, Pavel Machek wrote:

> Hi!
>
> > > > example 1: a laptop screen
> > > >
> > > > mode  capacity power description
> > > > 0        0        0    off
> > > > 1      100      100    full brightness
> > > > 2       70       60    half power to the backlight
> > > > 3       50       35    quarter power to the backlight
> > > > 4       30       25    eighth power to the backlight
> > > > 5        5       10    backlight off.
> > > >
> > > > example 2: a front-panel display on a server (no
> > > > variable backlight
> > > > control)
> > > >
> > > > mode capacity power description
> > > > 0       0        0   off
> > > > 1     100      100   backlight on
> > > > 2      50       10   backlight off
> > >
> > >
> > > the problem is: the person who SETS these needs to know
> > > what they mean.
> >
> > that's what the description is for. this info can be
> > provided by the driver as part of the list_modes()
> > function.
>
> That's what /sys/class/backlight/ is for :-).

yes it is, and each type of device is growing it's own, incompatible, 
interfaces for controlling things like this. I was aiming to do two 
things.

1. head this off and try and get a more common api

2. simplify the confusion that there is with multiple functions needing to 
be implemented during the suspend/resume cycle by chaning them from 
independant suspend-only functions to being just part of the device 
settings

> > > as someone who wrote (part of) a power policy manager;
> > > sorry but you
> > > take away information I need, and in addition the
> > > different API's are
> > > absolutely no big deal.
> >
> > assuming that nobody else chimes in to disagree with you
> > I'll accept your judgement and drop the issue.
>
> Just for the record, I agree with Arjan here.

oh well. sorry to take up everyone's time.

David Lang
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