Re: [PATCH v6 2/5] irqchip: Add RZ/G2L IA55 Interrupt Controller driver

[Philipp Zabel <p.zabel@pengutronix.de>]

On Sa, 2022-06-25 at 21:05 +0100, Lad Prabhakar wrote:
> Add a driver for the Renesas RZ/G2L Interrupt Controller.
> 
> This supports external pins being used as interrupts. It supports
> one line for NMI, 8 external pins and 32 GPIO pins (out of 123)
> to be used as IRQ lines.
> 
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
> ---
>  drivers/irqchip/Kconfig             |   8 +
>  drivers/irqchip/Makefile            |   1 +
>  drivers/irqchip/irq-renesas-rzg2l.c | 393 ++++++++++++++++++++++++++++
>  3 files changed, 402 insertions(+)
>  create mode 100644 drivers/irqchip/irq-renesas-rzg2l.c
> 
[...]
> diff --git a/drivers/irqchip/irq-renesas-rzg2l.c b/drivers/irqchip/irq-renesas-rzg2l.c
> new file mode 100644
> index 000000000000..cc16fcf2bbc6
> --- /dev/null
> +++ b/drivers/irqchip/irq-renesas-rzg2l.c
> @@ -0,0 +1,393 @@
[...]
> +static int rzg2l_irqc_init(struct device_node *node, struct device_node *parent)
> +{
> +	struct irq_domain *irq_domain, *parent_domain;
> +	struct platform_device *pdev;
> +	struct reset_control *resetn;
> +	struct rzg2l_irqc_priv *priv;
> +	int ret;
> +
> +	pdev = of_find_device_by_node(node);
> +	if (!pdev)
> +		return -ENODEV;
> +
> +	parent_domain = irq_find_host(parent);
> +	if (!parent_domain) {
> +		dev_err(&pdev->dev, "cannot find parent domain\n");
> +		return -ENODEV;
> +	}
> +
> +	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
> +	if (!priv)
> +		return -ENOMEM;
> +
> +	priv->base = devm_of_iomap(&pdev->dev, pdev->dev.of_node, 0, NULL);
> +	if (IS_ERR(priv->base))
> +		return PTR_ERR(priv->base);
> +
> +	ret = rzg2l_irqc_parse_interrupts(priv, node);
> +	if (ret) {
> +		dev_err(&pdev->dev, "cannot parse interrupts: %d\n", ret);
> +		return ret;
> +	}
> +
> +	resetn = devm_reset_control_get_exclusive_by_index(&pdev->dev, 0);

Why is this by index? I'd expect

	resetn = devm_reset_control_get_exclusive(&pdev->dev, NULL);

should work just as well?

regards
Philipp