[PATCH 1/6] PM: runtime: enable wake irq after runtime_suspend hook called

Tony Lindgren tony at atomide.com
Fri Apr 9 06:39:18 BST 2021


* Chunfeng Yun <chunfeng.yun at mediatek.com> [210409 01:54]:
> On Thu, 2021-04-08 at 19:41 +0200, Rafael J. Wysocki wrote:
> > On Thu, Apr 8, 2021 at 11:35 AM Chunfeng Yun <chunfeng.yun at mediatek.com> wrote:
> > >
> > > When the dedicated wake irq is level trigger, enable it before
> > > calling runtime_suspend, will trigger an interrupt.
> > >
> > > e.g.
> > > for a low level trigger type, it's low level at running time (0),
> > > and becomes high level when enters suspend (runtime_suspend (1) is
> > > called), a wakeup signal at (2) make it become low level, wake irq
> > > will be triggered.
> > >
> > >                 ------------------
> > >                |           ^     ^|
> > > ----------------           |     | --------------
> > >  |<---(0)--->|<--(1)--|   (3)   (2)    (4)
> > >
> > > if we enable the wake irq before calling runtime_suspend during (0),
> > > an interrupt will arise, it causes resume immediately;
> > 
> > But that's necessary to avoid missing a wakeup interrupt, isn't it?
> That's also what I worry about.

Yeah sounds like this patch will lead into missed wakeirqs.

Regards,

Tony



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