Re: [PATCH] gpio / ACPI: Handle ACPI events in accordance with the spec

From: Rafael J. Wysocki
Date: Wed Apr 10 2013 - 18:29:17 EST


On Wednesday, April 10, 2013 11:06:48 PM Linus Walleij wrote:
> On Tue, Apr 9, 2013 at 3:57 PM, Rafael J. Wysocki <rjw@xxxxxxx> wrote:
>
> > From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
> >
> > Commit 0d1c28a (gpiolib-acpi: Add ACPI5 event model support to gpio.)
> > that added support for ACPI events signalled through GPIO interrupts
> > covered only GPIO pins whose numbers are less than or equal to 255.
> > However, there may be GPIO pins with numbers greater than 255 and
> > the ACPI spec (ACPI 5.0, Section 5.6.5.1) requires the _EVT method
> > to be used for handling events corresponding to those pins.
> >
> > Moreover, according to the spec, _EVT is the default mechanism
> > for handling all ACPI events signalled through GPIO interrupts,
> > so if the _Exx/_Lxx method is not present for the given pin,
> > _EVT should be used instead. If present, though, _Exx/_Lxx take
> > precedence over _EVT which shouldn't be executed in that case
> > (ACPI 5.0, Section 5.6.5.3).
> >
> > Modify acpi_gpiochip_request_interrupts() to follow the spec as
> > described above and add acpi_gpiochip_free_interrupts() needed
> > to free interrupts associated with _EVT.
> >
> > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
>
> Patch applied with Mika's ACK, thanks!
>
> It's not like I fully understand it, but I totally trust you guys.

Well, thanks! :-)


--
I speak only for myself.
Rafael J. Wysocki, Intel Open Source Technology Center.
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