Re: [RFC] gpio: about the need to manage irq mapping dynamically.

From: Linus Walleij
Date: Thu Jun 29 2017 - 10:17:00 EST


On Tue, Jun 27, 2017 at 10:43 PM, Grygorii Strashko
<grygorii.strashko@xxxxxx> wrote:

> And my opinion is still the same here - It should be perfectly valid to create
> mappings from gpio_to_irq() to handle properly orthogonality of gpiochip and
> gpio-irqchip functionality and satisfy SPARSE_IRQ goal (allocate Linux virq and
> irq descriptors on demand).

You are right.

I would rather say: GPIO drivers that have a 1-to-1 mapping between GPIO
lines and IRQs should not do it, they should map up them all at probe().

Drivers that actually have fewer IRQs than GPIO lines should be able to
create the mappings in gpio_to_irq().

Yours,
Linus Walleij