On Mon, Sep 11, 2006 at 05:17:01PM -0700, Mark Gross wrote:

cpufreq is broken at the cpufreq_driver interface for embedded
applications needing control over more than one control variable at a
time.

That interface only supports setting target frequencies, and expanding it
to set target frequencies and voltages is not possible without something
like PowerOP.  Adding the types of parameters to cpufreq would likely
make cpufreq a mess.  I think we would be better off with something that
coexists with cpufreq, like the powerop patch from Eugeny.

God help you if you try to use cpufreq on a complex non-PC platform with
multiple power and clock domains that need to be tweaked to squeeze out
competitive battery life.

Because of the existing user base of cpufreq removing cpufreq will never
happen.  No one supporting the PowerOP patch has never recommended
such a thing.  However; holding back innovation because of an existing
solution that doesn't support a large class of users seems dumb.

But you can't break the existing stuff, and it seems that some of these
proposals are doing just that. :(

thanks,

greg k-h