[PATCH] pinctrl/nomadik: allocate IRQ descriptors dynamically

[swarren@nvidia.com (Stephen Warren)]

On 09/26/2012 11:18 AM, Linus Walleij wrote:
> From: Linus Walleij <linus.walleij@linaro.org>
> 
> This allocates the IRQ descriptors for the Nomadik pin controller
> dynamically so that we don't have to rely on some other mechanism
> doing it, and moving a step closer to a linear IRQ domain.
> 
> Cc: Rob Herring <rob.herring@calxeda.com>
> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
> ---
>  drivers/pinctrl/pinctrl-nomadik.c | 19 +++++++++++++++++--
>  1 file changed, 17 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/pinctrl/pinctrl-nomadik.c b/drivers/pinctrl/pinctrl-nomadik.c
> index 3dde653..29921d1 100644
> --- a/drivers/pinctrl/pinctrl-nomadik.c
> +++ b/drivers/pinctrl/pinctrl-nomadik.c
> @@ -1185,6 +1185,8 @@ static int __devinit nmk_gpio_probe(struct platform_device *dev)
>  	struct clk *clk;
>  	int secondary_irq;
>  	void __iomem *base;
> +	int irq_start;
> +	int irq_base;
>  	int irq;
>  	int ret;
>  
> @@ -1288,9 +1290,22 @@ static int __devinit nmk_gpio_probe(struct platform_device *dev)
>  
>  	platform_set_drvdata(dev, nmk_chip);
>  
> +	/*
> +	 * Allocate descriptors and IRQ domain using the legacy model, this
> +	 * should eventually be replaced with a linear IRQ domain as we get
> +	 * independent from the irq numbers with the switch to device tree.
> +	 */
> +	irq_start = NOMADIK_GPIO_TO_IRQ(pdata->first_gpio);

Presumably that's a 1:1 mapping...

> +	irq_base = irq_alloc_descs(irq_start, 0, NMK_GPIO_PER_CHIP,
> +				   numa_node_id());
> +	if (IS_ERR_VALUE(irq_base)) {
> +		WARN(1, "Cannot allocate irq_descs @ IRQ%d, assuming pre-allocated\n",
> +		     irq_start);
> +		irq_base = irq_start;
> +	}

Hmmm. Is this code targetting the DT case or the non-DT case or both? I
think typically you'd call irq_domain_add_linear without forcing a
particular IRQ base for the DT case, and only call irq_alloc_descs() for
the non-DT case, right?

>  	nmk_chip->domain = irq_domain_add_legacy(np, NMK_GPIO_PER_CHIP,
> -						NOMADIK_GPIO_TO_IRQ(pdata->first_gpio),
> -						0, &nmk_gpio_irq_simple_ops, nmk_chip);
> +				irq_base, 0,
> +				&nmk_gpio_irq_simple_ops, nmk_chip);
>  	if (!nmk_chip->domain) {
>  		dev_err(&dev->dev, "failed to create irqdomain\n");
>  		ret = -ENOSYS;