Re: [PATCH 0/3] cpufreq: dt: Create platform device from generic code

[Arnd Bergmann <arnd@arndb.de>]

On Friday 25 March 2016 10:11:24 Viresh Kumar wrote:
> On 24-03-16, 15:16, Arnd Bergmann wrote:
> > Hmm, can you give an example where this is needed?
> 
> I don't remember them, but I am quite sure that I have seen people
> asking for that support again and again.
> 
> > I assume you are
> > thinking of some clock controller or regulator that gets initialized
> > after the cpufreq driver, right?
> 
> Yeah.
> 
> > Are there any that are in loadable modules, rather than just later
> > in the init sequence for built-in drivers?
> 
> Maybe both, don't remember. Sorry.
> 
> Over that, independent of what the users are doing today, I think its
> important to support defer probing for anyone that wants to use it.

Ok.

> > I think we do care about compatibility there, but there are clearly
> > other ways to handle the special case for opp-v1 if we want to.
> 
> Okay, and what are those ? There is only one platform which has used
> the pdata, mvebu.

The platform already calls dev_pm_opp_add(), so it directly interacts
with the cpufreq infrastructure. One way to do it would be to add
another function call to set the independent_clocks flag in a static
variable owned by that. Another way would be to have a separate
function call for doing dev_pm_opp_add() with independent clocks.
As far as I can tell, the two (dev_pm_opp_add and independent_clocks)
are already tightly coupled interfaces, so it makes sense to
combine them.

	Arnd