Messages in this thread | | | Date | Sun, 16 Dec 2012 10:29:47 -0500 (EST) | From | Alan Stern <> | Subject | Re: [Resend][PATCH] PM: Move disabling/enabling runtime PM to late suspend/early resume |
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On Sun, 16 Dec 2012, Rafael J. Wysocki wrote:
> On Saturday, December 15, 2012 10:16:29 PM Jiri Kosina wrote: > > On Sat, 15 Dec 2012, Rafael J. Wysocki wrote: > > > > > From: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > > > > > > Currently, the PM core disables runtime PM for all devices right > > > after executing subsystem/driver .suspend() callbacks for them > > > and re-enables it right before executing subsystem/driver .resume() > > > callbacks for them. This may lead to problems when there are > > > two devices such that the .suspend() callback executed for one of > > > them depends on runtime PM working for the other. In that case, > > > if runtime PM has already been disabled for the second device, > > > the first one's .suspend() won't work correctly (and analogously > > > for resume). > > > > > > To make those issues go away, make the PM core disable runtime PM > > > for devices right before executing subsystem/driver .suspend_late() > > > callbacks for them and enable runtime PM for them right after > > > executing subsystem/driver .resume_early() callbacks for them. This > > > way the potential conflitcs between .suspend_late()/.resume_early() > > > and their runtime PM counterparts are still prevented from happening, > > > but the subtle ordering issues related to disabling/enabling runtime > > > PM for devices during system suspend/resume are much easier to avoid. > > > > > > Reported-and-tested-by: Jan-Matthias Braun <jan_braun@gmx.net> > > > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> > > > > Hi Rafael, > > > > just curious what is the reason for resend? Do you want to gather more > > Acks before pushing this upstream? > > Well, I thought that some people might actually look at it when they found it > again in their mailboxes. :-)
I did look at it the first time it appeared. It seemed to be okay, but I haven't tried any testing.
Alan Stern
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