RE: [PATCH v2] ACPI / sleep: EC-based wakeup from suspend-to-idle on recent systems

From: Mario.Limonciello
Date: Fri Jun 23 2017 - 14:01:39 EST


> -----Original Message-----
> From: Srinivas Pandruvada [mailto:srinivas.pandruvada@xxxxxxxxxxxxxxx]
> Sent: Friday, June 23, 2017 11:06 AM
> To: Limonciello, Mario <Mario_Limonciello@xxxxxxxx>; rjw@xxxxxxxxxxxxx; linux-
> acpi@xxxxxxxxxxxxxxx
> Cc: linux-pm@xxxxxxxxxxxxxxx; andriy.shevchenko@xxxxxxxxxxxxxxx;
> dvhart@xxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx;
> mika.westerberg@xxxxxxxxxxxxxxx; tom@xxxxxxxxxxxxx;
> jerome.debretagne@xxxxxxxxx; torvalds@xxxxxxxxxxxxxxxxxxxx;
> lv.zheng@xxxxxxxxx
> Subject: Re: [PATCH v2] ACPI / sleep: EC-based wakeup from suspend-to-idle on
> recent systems
>
> On Fri, 2017-06-23 at 15:37 +0000, Mario.Limonciello@xxxxxxxx wrote:
>
> [...]
>
> > >
> > > +#define ACPI_LPS0_SCREEN_ON 4
> > > +#define ACPI_LPS0_ENTRY 5
> > > +#define ACPI_LPS0_EXIT 6
> > The spec you shared also defines device constraints (function 1). It
> > would be very
> > useful if these constraintsÂÂcould be parsed and compared against the
> > actual power
> > states of devices on the system at least for debugging purposes.ÂÂI'm
> > not sure if you
> > already had a plan for that in a future series.
> >
> For debug purpose, I have worked on a patch to dump the constraint
> table in debugfs. But in the freeze path whether we meet the
> constraints or not will not make any difference, other than for just
> debugging.
>
> Thanks,
> Srinivas

Right that was what I thought would be most interesting. You can potentially
output to syslog as a last step going down what isn't in the right state to match
the constraint table.