Re: [PATCH] PM: Hide CONFIG_PM from users

From: Rafael J. Wysocki
Date: Mon Feb 07 2011 - 18:06:37 EST


On Monday, February 07, 2011, Dmitry Torokhov wrote:
> On Mon, Feb 07, 2011 at 11:00:03PM +0100, Rafael J. Wysocki wrote:
> > On Monday, February 07, 2011, Dmitry Torokhov wrote:
> > > On Mon, Feb 07, 2011 at 10:15:59PM +0100, Rafael J. Wysocki wrote:
> > > > On Monday, February 07, 2011, Mark Brown wrote:
> > > > >
> > > > > Yeah, but some people seem very keen on removing the pointers to the PM
> > > > > ops entirely when CONFIG_PM is disabled which means that you end up with
> > > > > varying idioms for what you do with the PM ops as stuff gets ifdefed
> > > > > out. Then again I'm not sure anything would make those people any
> > > > > happier.
> > > >
> > > > I really think we should do things that makes sense rather that worry about
> > > > who's going to like or dislike it (except for Linus maybe, but he tends to like
> > > > things that make sense anyway). At this point I think the change I suggested
> > > > makes sense, because it (a) simplifies things and (b) follows the quite common
> > > > practice which is to make PM callbacks depend on CONFIG_PM.
> > >
> > > Many people make these callback dependent on PM not because it makes
> > > much sense but because it is possible to do so. However, aside of
> > > randconfig compile testing, nobody really tests drivers that implement
> > > PM in the !CONFIG_PM setting.
> >
> > That I can agree with, but I'm not sure whether it is an argument against
> > the patch I've just posted or for it?
>
> More of an observation for your (b) justification. I'd probably force
> CONFIG_PM to always 'y'w while we weeding references to it from
> drivers...

We simply can't force CONFIG_PM to 'y', because some platforms want it to be 'n'.

OTOH, if CONFIG_PM = CONFIG_PM_SLEEP||CONFIG_PM_RUNTIME, we can just leave the
#ifdefs as they are and simply avoid adding new ones, or use CONFIG_PM for all
PM callbacks.

Thanks,
Rafael
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