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

[Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>]

On Wed, 2017-01-11 at 14:12 +0100, Linus Walleij wrote:
> 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?

Correct, I'm doing it right now. Takes time to do and to test of course.

-- 
Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Intel Finland Oy
--
To unsubscribe from this list: send the line "unsubscribe linux-gpio" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html