Re: [PATCH v5 1/2] gpio: sch: Add edge event support

[Linus Walleij]

On Wed, Mar 17, 2021 at 4:19 PM Andy Shevchenko
<andriy.shevchenko@xxxxxxxxxxxxxxx> wrote:

> From: Jan Kiszka <jan.kiszka@xxxxxxxxxxx>
>
> Add the required infrastructure to enable and report edge events
> of the pins to the GPIO core. The actual hook-up of the event interrupt
> will happen separately.
>
> Signed-off-by: Jan Kiszka <jan.kiszka@xxxxxxxxxxx>
> Co-developed-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>

I can't believe it that nobody added irq support to this driver for 10
years given how widely deployed it is! (Good work.)

Don't you need to add

select GPIOLIB_IRQCHIP

to Kconfig? So the gpio_chip contains the .irq member you're using.

> +       sch->irqchip.name = "sch_gpio";
> +       sch->irqchip.irq_ack = sch_irq_ack;
> +       sch->irqchip.irq_mask = sch_irq_mask;
> +       sch->irqchip.irq_unmask = sch_irq_unmask;
> +       sch->irqchip.irq_set_type = sch_irq_type;
> +
> +       sch->chip.irq.chip = &sch->irqchip;
> +       sch->chip.irq.num_parents = 0;
> +       sch->chip.irq.parents = NULL;
> +       sch->chip.irq.parent_handler = NULL;
> +       sch->chip.irq.default_type = IRQ_TYPE_NONE;
> +       sch->chip.irq.handler = handle_bad_irq;

I always add a local variable like:

struct gpio_irq_chip *girq;

And assign with the arrow, so as to make it easier to read:

girq->parent_handler = NULL

etc.

+/- the above:
Reviewed-by: Linus Walleij <linus.walleij@xxxxxxxxxx>

Yours,
Linus Walleij