Re: [PATCH v4 3/7] gpio: gpiolib: Add ngirq member to struct gpio_irq_chip

[Linus Walleij]

On Wed, May 18, 2022 at 9:30 PM Lad Prabhakar
<prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx> wrote:

> Supported GPIO IRQs by the chip is not always equal to the number of GPIO
> pins. For example on Renesas RZ/G2L SoC where it has GPIO0-122 pins but at
> a given point a maximum of only 32 GPIO pins can be used as IRQ lines in
> the IRQC domain.
>
> This patch adds ngirq member to struct gpio_irq_chip and passes this as a
> size to irq_domain_create_hierarchy()/irq_domain_create_simple() if it is
> being set in the driver otherwise fallbacks to using ngpio.
>
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>

NAK

As pointed out this is a property of the hardware and thus you should
derive this property of the hardware from the compatible string.

For example by passing per-variant .data in struct of_device_id.

Unique hardware properties means unique hardware means it should
have a unique compatible string. Otherwise something is wrong
with the compatibles.

Yours,
Linus Walleij