Re: [PATCH v1 1/2] pinctrl: baytrail: Do not add all GPIOs to IRQ domain

[Linus Walleij <linus.walleij@xxxxxxxxxx>]

On Wed, Jan 11, 2017 at 11:27 AM, Mika Westerberg
<mika.westerberg@xxxxxxxxxxxxxxx> wrote:
> On Tue, Jan 10, 2017 at 10:11:38PM +0200, Andy Shevchenko wrote:
>> It turns out that for some GPIO pins interrupts are bypassing standard
>> chain.
>>
>> Now the reason why some events such as touchscreen communication on ASuS
>> T100TA does not work if we mask all the interrupts is that in order to
>> generate either interrupts or GPEs the INTMASK register must have that
>> particular interrupt unmasked. In case of GPEs the CPU does not trigger
>> normal interrupt (and thus the GPIO driver does not see it) but instead
>> it causes SCI (System Control Interrupt) to be triggered with the GPE in
>> question set.
>>
>> To make this all work as expected we add those GPIOs to the IRQ
>> domain that can actually generate interrupts and skip others.
>
> Actually what happens is that when DIRECT_IRQ_EN is set, the pin is
> routed directly to the IO-APIC bypassing the GPIO driver completely.
> However, the mask register is still used to determine if the pin is
> supposed to generate IRQ or not.
>
> So with commit 3ae02c14d964 the IRQ core masks all IRQs (because of
> handle_bad_irq()) the pin connected to the touchscreen gets masked as
> well and hence no interrupts.
>
> This has nothing to do with GPEs, though.
>
> The fix itself looks good to me.

So I guess I wait for a commit with updates commit message
and then apply that for fixes?

Yours,
Linus Walleij
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