Re: [PATCH 2/2] gpio: sch: Add interrupt support

[Jan Kiszka]

On 24.04.19 10:18, Mika Westerberg wrote:
> On Wed, Apr 24, 2019 at 10:12:42AM +0200, Jan Kiszka wrote:
> > On 24.04.19 09:58, Mika Westerberg wrote:
> > > +Rafael and linux-acpi.
> > >
> > > On Thu, Apr 18, 2019 at 11:23:49AM +0200, Jan Kiszka wrote:
> > > > From: Jan Kiszka <jan.kiszka@xxxxxxxxxxx>
> > > >
> > > > Validated on the Quark platform, this adds interrupt support on rising
> > > > and/or falling edges.
> > >
> > > The irqchip parts look good to me but but the ACPI SCI handling seems
> > > weird. This is typically handled by ACPI core based on the values read
> > > from FADT ACPI table. What does it contain on this Quark platform?
> >
> > There is no FADT on the original Quark firmware, nor did we add one. As we
> > are talking about existing devices, possibly not only Quarks, I was going
> > down the ACPI-independent way to hook into the interrupt. But I'm open to
> > learn about better alternatives.
>
> Hmm, if it does not have FADT table why would you need SCI then? Is this
> implementing some real use case?

Maybe I'm looking at the wrong place: Where would I find it? There is definitely 
no separate entry under /sys/firmware/acpi/tables - but that's also true for my 
workstation.

In any case: The hardware defines that the GPIO events are sent via SCIs. That 
fact is probably not expressed in ACPI language.

Jan

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