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

From: Linus Walleij
Date: Wed Apr 10 2013 - 17:06:53 EST


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.

Yours,
Linus Walleij
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