Re: [PATCH] mfd: cottula: add cottula board

[Arnd Bergmann <arnd@arndb.de>]

On Monday 15 December 2014 00:10:06 Robert Jarzmik wrote:
> +
> +       platform_set_drvdata(pdev, cot);
> +       cot->gpio0 = gpiod_get(&pdev->dev, "lubbock_irq", 0);
> +       if (IS_ERR(cot->gpio0)) {
> +               dev_err(&pdev->dev, "Couldn't request GPIO : ret = %d\n", ret);
> +               return PTR_ERR(cot->gpio0);
> +       }
> +       cot->irq = gpiod_to_irq(cot->gpio0);
> +       if (cot->irq < 0)
> +               return cot->irq;
> +
> +       cot->irqdomain =
> +               irq_domain_add_linear(pdev->dev.of_node, COTTULA_NB_IRQ,
> +                                     &cottula_irq_domain_ops, cot);
> +       if (!cot->irqdomain)
> +               return -ENODEV;
> +
> +       ret = 0;
> +       if (base_irq)
> +               ret = irq_create_strict_mappings(cot->irqdomain, base_irq, 0,
> +                                                COTTULA_NB_IRQ);
> 

This looks a bit ambiguous: You get a GPIO line for the purpose of the
IRQ nesting but don't use the GPIO otherwise, and you pass the device's
own irq domain start as an IORESOURCE_IRQ resource.

For consistency between DT and ATAGS based uses, and with similar DT
based drivers, I would instead recommend passing the parent irq (from
the GPIO) as an IORESOURCE_IRQ resource instead of a gpio lookup,
and passing the base_irq as platform_data for the ATAGS case.

	Arnd