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From: "Rafael J. Wysocki" <rjw@sisk.pl>
To: Kevin Hilman <khilman@ti.com>
Subject: Re: [RFC][PATCH] Power domains for platform bus type
Date: Tue, 1 Feb 2011 11:52:20 +0100
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On Tuesday, February 01, 2011, Kevin Hilman wrote:
> "Rafael J. Wysocki" <rjw@sisk.pl> writes:
> 
> > Hi,
> >
> > This is something we discussed during the last Linux Plumbers Conference.
> >
> > The problem appears to be that the same device may be used in different
> > systems in different configurations such that actions necessary for the
> > device's power management can vary from one system to another.  In those
> > cases the drivers' power management callbacks are generally not sufficient,
> > because they can't take the configuration of the whole system into account.
> >
> > I think this issue may be addressed by adding objects that will represent
> > power domains and will provide power management callbacks to be executed
> > in addition to the device driver's PM callbacks, which is done by the patch
> > below.
> >
> > Please have a look at it and tell me what you think.
> >
> 
> FYI... I just tested this patch on OMAP by converting our existing use
> of platform_bus_set_ops() to use this approach by adding a powerdomain
> to each omap_device.   
> 
> Note we're currently only overriding the runtime_[suspend|resume]
> methods, so those are the only paths I've tested.

Thanks a lot for the testing!

I'm going to prepare a new version of the patch that will add power domain
objects at the core level (ie. struct device).

Rafael