Re: [PATCH] pinctrl: cherryview: Read triggering type from HW if not set when requested

[Linus Walleij <linus.walleij@xxxxxxxxxx>]

On Tue, May 12, 2015 at 12:35 PM, Mika Westerberg
<mika.westerberg@xxxxxxxxxxxxxxx> wrote:

> If a driver does not set interrupt triggering type when it calls
> request_irq(), it means use the pin as the hardware/firmware has
> configured it. There are some drivers doing this. One example is
> drivers/input/serio/i8042.c that requests the interrupt like:
>
>         error = request_irq(I8042_KBD_IRQ, i8042_interrupt, IRQF_SHARED,
>                             "i8042", i8042_platform_device);
>
> It assumes the interrupt is already properly configured. This is true in
> case of interrupts connected to the IO-APIC. However, some Intel
> Braswell/Cherryview based machines use a GPIO here instead for the internal
> keyboard controller.
>
> This is a problem because even if the pin/interrupt is properly configured,
> the irqchip ->irq_set_type() will never be called as the triggering flags
> are 0. Because of that we do not have correct interrupt flow handler set
> for the interrupt.
>
> Fix this by adding a custom ->irq_startup() that checks if the interrupt
> has no triggering type set and in that case read the type directly from the
> hardware and install correct flow handler along with the mapping.
>
> Reported-by: Jagadish Krishnamoorthy <jagadish.krishnamoorthy@xxxxxxxxx>
> Reported-by: Freddy Paul <freddy.paul@xxxxxxxxx>
> Signed-off-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>

Patch applied for fixes.

Yours,
Linus Walleij
--
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