[PATCH v2 0/3] ACPI / sleep: Support power button wakeup from S2I on recent Dell laptops

Rafael J. Wysocki
2017-06-19T22:01:32Z

Hi All,

On Thursday, June 01, 2017 01:23:43 AM Rafael J. Wysocki wrote:
>
> This is a follow-up for a patch series posted some time ago:
>
> http://marc.info/?l=linux-kernel&m=149324246701378&w=2
>
> The first two patches from that series are in 4.12-rc already and the rest
> have been rearranged.

Here's a v2 of the above.

The first two patches are actually the same as before, only with ACKs from Andy.

The third patch is almost the same, but it adds a new command line switch to
go back to the semi-functional power button wakeup from s2idle if someone
really wants that.

> The issue at hand is still the same as before:
>
> On Wednesday, April 26, 2017 11:21:11 PM Rafael J. Wysocki wrote:
> >
> > The underlying issue is that on some relatively new Dell laltops, including
> > Dell XPS13 9360 and 9365, pressing the power button is not sufficient to
> > wake up the system from suspend-to-idle (it has to be pressed and held
> > down for around 5 sec for the wakeup to happen) which is not expected
> > and does not match the Windows' behavior.
> >
> > This turns out to be a consequence of the way power button events are signaled
> > on those systems, which is through the Embedded Controller (EC). Namely,
> > button events go to the EC which then signals the event through its ACPI GPE
> > (General Purpose Event), which triggers an ACPI SCI (System Control Interrupt),
> > whose handler executes a specicif AML control method and triggers a Notify()
> > targetting a devie object associated with the power button. The problem with
> > suspend-to-idle is that the EC GPE is disabled during suspend, because
> > otherwise all EC events would wake up the system from suspend-to-idle (and
> > there can be many of them).
>
> The first two patches in the current series update the drivers used for button
> events processing on the affected systems so that they signal wakeup as
> expected and avoid propagating the wakeup events as button events to user
> space.
>
> The third patch allows the EC GPE to become a wakeup GPE on the affected Dell
> laptops and finally makes power button events wake up those systems from
> suspend-to-idle.
>
> After this series there still is a concern regarding the possible increase of
> power draw that may result from the processing of non-wakeup EC events while
> suspended which is why the change only affects Dell XPS13 9360 and 9365
> for now.
>
> There is no code dependency between patches [1-2/3] and patch [3/3], but all
> of them together are necessary for the feature in question to work on both the
> affected systems, so IMO they should be applied together.

The series is based on current linux-next. It is available from a git branch at

git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm.git s2idle-dell-test

and has been included into the testing branch thereof.

If there are any concerns regarding this series, please let me know.

Thanks,
Rafael