Re: Help me fix a regression caused by 56b9918490 (PM: sleep: Simplify suspend-to-idle control flow)

["Rafael J. Wysocki" <rafael@kernel.org>]

On Wed, Nov 27, 2019 at 3:35 AM Kenneth R. Crudup <kenny@panix.com> wrote:
>
>
> On Tue, 26 Nov 2019, Kenneth R. Crudup wrote:
>
> > So there were some 5 times where my laptop spontaneously (I'll bet it was
> > that damned accelerometer) woke up, sometimes for minutes at at time, all
> > the while in my laptop bag.
> ...
> > But the great news about this is this maybe explains why I'll try and resume
> > after being mobile; whatever awakening we used to do wouldn't be handled
> > (again, guessing :)) and we'd freeze up.
>
> So I'd just realized something- when you'd first pushed the series of commits
> changing the S2idle flow, I'd sent an E-mail about some issues I'd had:
>
> ----
> Date: Wed, 18 Sep 2019 18:05:53
> From: Kenneth R. Crudup <kenny@panix.com>
> To: rafael.j.wysocki@intel.com
> Cc: linux-pm@vger.kernel.org
> Message-ID: <alpine.DEB.2.21.1909181742470.2771@hp-x360n>
> Subject: Help me help you debug what seems to be an EC resume issue
> ...
> >>> Before these commits, I used to set "acpi.ec_no_wakeup=1" because the
> >>> orientation sensor (at least, and probably other things) would wake up
> >>> the laptop (then immediately suspend), which I'm sure was using up
> >>> battery while I'm just walking around.
> >>> I've turned off "ec_no_wakeup" for testing and the good news is the
> >>> orientation sensor doesn't cause the laptop to draw more power when shaking it.
> ----
>
> Whoops- I guess in the face of everything we now know, that was indeed a
> bug and not a feature, because I'd also posted:
>
> >>>  Randomly, if left suspended, nothing other than a hard power off will get
> >>>  it back (and I can't be sure, but I think current consumption can be normal
> >>>  when it suspends, but this seems to only happen if I've unplugged the
> >>>  charger after suspending (so no power meter))
>
> So now we know.
>
> So, now that apparently (fingers still crossed, but so far, so very good)
> you've squashed that resume bug, do I have any recourse about this thing
> waking up for just by staring at it very hard other than "ec_no_wakeup=1"?
>
> Personally I don't mind at all having the keyboard being the only thing
> that'll take the laptop out of suspend, and the only reason I was looking
> for not having to modify the EC operation was 'cause I thought having that
> set meant we'd short-circuited some other s2idle optimization, and I'm
> constantly trying to minimize s2idle power consumption.
>
> If all "ec_no_wakeup=1" actually does is silently ignore EC wakeup events,
> then I'll stick with it.

Yes, that's all it does.