On Monday, December 17, 2012 10:18:14 PM Ulf Hansson wrote: > On 16 December 2012 16:29, Alan Stern <[email protected]> wrote: > > 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 <[email protected]> > >> > > > >> > > 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 <[email protected]> > >> > > Signed-off-by: Rafael J. Wysocki <[email protected]> > >> > > >> > 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 > > > > -- > > To unsubscribe from this list: send the line "unsubscribe linux-pm" in > > the body of a message to [email protected] > > More majordomo info at http://vger.kernel.org/majordomo-info.html > > I believe this should work fine for ux500 platforms, so: > > Reviewed-by: Ulf Hansson <[email protected]>
Thanks! -- I speak only for myself. Rafael J. Wysocki, Intel Open Source Technology Center. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
