Re: community PM requirements/issues and PowerOP [Was: Re: So, what's the status on the recent patches here?]

[Pavel Machek <pavel@ucw.cz>]

On Mon 2006-09-11 17:36:33, Preece Scott-PREECE wrote:
> 
> > From: Pavel Machek [mailto:pavel@ucw.cz] 
> > 
> > > >>- PowerOP is only one layer (towards the bottom) in a power 
> > > >>management solution.
> > > >>- PowerOP does *not* replace cpufreq
> > > >
> > > >PowerOP provides userland interface for changing processor 
> > frequency. 
> > > >That's bad -- duplicate interface.
> > > Basically the biggest problem with cpufreq interface is 
> > that cpufreq 
> > > has "chose predefined closest to a given frequency" functionality 
> > > implemented in the kernel while there is _no_ any reason to 
> > have this 
> > > functionality implemented in the kernel if we have sysfs interface 
> > > exported by PowerOP in place - you just
> > 
> > No, there is reason to keep that in kernel -- so that cpufreq 
> > userspace interface can be kept, and so that resulting 
> > kernel<->user interface is not ugly.
> ---
> 
> Just as a data point, "keeping the cpufreq interface" is
> irrelevant to a number of us, because we configure it out
> of the system.  I'm not really arguing that we should get
> rid of an existing kernel interface, but I don't see any
> reason why we shouldn't be able to have a separately
> configurable interface if cpufreq doesn't meet our needs.

Configurable interfaces are evil, and I do not think you can push such
patch. You have developed your own little interface that suits your
needs -- and that's fine -- but now you are trying to push it into
mainline... and that is not, because those interfaces were not really
designed to work together.
								Pavel
-- 
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