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

["Kenneth R. Crudup" <kenny@panix.com>]

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.

Thanks,

	-Kenny

-- 
Kenneth R. Crudup  Sr. SW Engineer, Scott County Consulting, Silicon Valley