From: "Rafael J. Wysocki" <rjw@sisk.pl>
To: Alan Stern <stern@rowland.harvard.edu>
Subject: Re: [PATCH 1/2] PM / Runtime: Clean up pm_runtime_disable()
Date: Fri, 29 Jan 2010 16:01:37 +0100
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On Friday 29 January 2010, Alan Stern wrote:
> On Thu, 28 Jan 2010, Rafael J. Wysocki wrote:
> 
> > > > - * If @check_resume is set and there's a resume request pending when
> > > > - * __pm_runtime_disable() is called and power.disable_depth is zero, the
> > > > - * function will wake up the device before disabling its run-time PM.
> > > >   */
> > > > -void __pm_runtime_disable(struct device *dev, bool check_resume)
> > > > +void pm_runtime_disable(struct device *dev)
> > > >  {
> > > 
> > > Why did you decide to remove the check_resume argument?  That decision 
> > > should be explained in the patch description.
> > 
> > Well, I thought the "which is not necessary any more" would be a sufficient
> > explanation ...
> 
> But why is it not necessary now,

Well, all of the existing callers use only one value of it, which is 'false'
(perhaps I should write that in the changelog).

> given that apparently it was necessary before?  What has changed to make
> it unnecessary?

It was used in the system suspend code path in main.c (in dpm_prepare()) IIRC,
but it was replaced by the current code.

I don't really think it's useful to try to recall why it was used at one point.
It's not used now and I don't have a usage case for it.  If no one else knows
it will be necessary, removing it is the right thing to do.

Rafael
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