Re: [PATCH v3 1/2] gpio: Add support for hierarchical IRQ domains

[Linus Walleij]

On Wed, May 29, 2019 at 4:53 PM Thierry Reding <thierry.reding@xxxxxxxxx> wrote:

> From: Thierry Reding <treding@xxxxxxxxxx>
>
> Hierarchical IRQ domains can be used to stack different IRQ controllers
> on top of each other. One specific use-case where this can be useful is
> if a power management controller has top-level controls for wakeup
> interrupts. In such cases, the power management controller can be a
> parent to other interrupt controllers and program additional registers
> when an IRQ has its wake capability enabled or disabled.
>
> Signed-off-by: Thierry Reding <treding@xxxxxxxxxx>
> ---
> Changes in v3:
> - use irq_create_fwspec_mapping() instead of irq_domain_alloc_irqs()
> - add missing kerneldoc for new parent_domain field
> - keep IRQ_DOMAIN dependency for clarity

Actually I applied the patch, and dropped the two lines making
it possible to override .to_irq() for now, so I can illustrate my
idea on top. If I manage.

Yours,
Linus Walleij