Re: [PATCH] RFC: pinctrl: cherryview: Pass irqchip when adding gpiochip

[Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>]

On Tue, Aug 13, 2019 at 09:01:23AM +0200, Linus Walleij wrote:
> We need to convert all old gpio irqchips to pass the irqchip
> setup along when adding the gpio_chip. For more info see
> drivers/gpio/TODO.
> 
> This driver is something of a special case, so we need to
> discuss it.
> 
> It picks a number of IRQ descriptors before setting up
> the gpio_irq_chip using devm_irq_alloc_descs() giving a
> fixed irq base in the IRQ numberspace. It then games the
> irqchip API by associating IRQs from that base and upward
> with as many pins there are in the "community" which is a
> set of pins. Then after each gpio_chip is registered, it
> fills in the pin to IRQ map for each GPIO range inside
> that "community" with irq_domain_associate_many() which
> works fine since the descriptors were allocated
> previously.
> 
> This is actually a hierarchical irq_chip as far as I can
> tell. The problem is that very likely the Intel root IRQ
> chip is not hierarchical so it does not support using the
> facilities for hierarchical irqdomains.
> 
> I will soon merge the patch providing hierarchical irqchip
> support in gpiolib:
> https://lore.kernel.org/linux-gpio/20190808123242.5359-1-linus.walleij@xxxxxxxxxx/
> 
> Will we need to bite the bullet and convert the root
> irqchip for the intels to support hierarcical irqdomain?

We have few fixes for this driver, perhaps you can send a new version based on
them when they appear in your tree.

-- 
With Best Regards,
Andy Shevchenko