On Wed, Nov 20, 2019 at 08:20:14PM +0100, Jan Kiszka wrote:
> From: Jan Kiszka <jan.kiszka@xxxxxxxxxxx>
>
> The ACPI description on the Quark platform does not provide the required
> information to do establish generic handling. Therefore, we need to hook
> from the driver directly into SCI handler of the ACPI subsystem in order
> to catch and report GPIO-related events.
>
> Validated on the Quark-based IOT2000 platform.
>
> Signed-off-by: Jan Kiszka <jan.kiszka@xxxxxxxxxxx>
Reviewed-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>
Below one minor stylistic comment.
> ---
> drivers/gpio/gpio-sch.c | 30 ++++++++++++++++++++++++++++++
> 1 file changed, 30 insertions(+)
>
> diff --git a/drivers/gpio/gpio-sch.c b/drivers/gpio/gpio-sch.c
> index 6a9c5500800c..75c95da145d8 100644
> --- a/drivers/gpio/gpio-sch.c
> +++ b/drivers/gpio/gpio-sch.c
> @@ -155,6 +155,31 @@ static const struct gpio_chip sch_gpio_chip = {
> .to_irq = sch_gpio_to_irq,
> };
>
> +static u32 sch_sci_handler(void *context)
> +{
> + struct sch_gpio *sch = context;
> + unsigned long core_status, resume_status;
> + unsigned int resume_gpios, offset;
> +
> + core_status = inl(sch->iobase + GTS);
> + resume_status = inl(sch->iobase + GTS + 0x20);
> +
> + if (core_status == 0 && resume_status == 0)
You can also write this like
if (!core_status &&& !resume_status)
> + return ACPI_INTERRUPT_NOT_HANDLED;
> +
> + for_each_set_bit(offset, &core_status, sch->resume_base)
> + generic_handle_irq(sch->irq_base + offset);
> +
> + resume_gpios = sch->chip.ngpio - sch->resume_base;
> + for_each_set_bit(offset, &resume_status, resume_gpios)
> + generic_handle_irq(sch->irq_base + sch->resume_base + offset);
> +
> + outl(core_status, sch->iobase + GTS);
> + outl(resume_status, sch->iobase + GTS + 0x20);
> +
> + return ACPI_INTERRUPT_HANDLED;
> +}
> +
> static int sch_irq_type(struct irq_data *d, unsigned int type)
> {
> struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
> @@ -215,6 +240,7 @@ static int sch_gpio_probe(struct platform_device *pdev)
> struct irq_chip_type *ct;
> struct sch_gpio *sch;
> struct resource *res;
> + acpi_status status;
> int irq_base, ret;
>
> sch = devm_kzalloc(&pdev->dev, sizeof(*sch), GFP_KERNEL);
> @@ -303,6 +329,10 @@ static int sch_gpio_probe(struct platform_device *pdev)
> if (ret)
> return ret;
>
> + status = acpi_install_sci_handler(sch_sci_handler, sch);
> + if (ACPI_FAILURE(status))
> + return -EINVAL;
> +
> return 0;
> }
>
> --
> 2.16.4
