Re: [PATCH v6 2/5] irqchip/irq-goldfish-pic: Add Goldfish PIC driver

[Marc Zyngier]

On Mon, Oct 30 2017 at 12:56:33 pm GMT, Aleksandar Markovic <aleksandar.markovic@xxxxxxxxx> wrote:
> From: Miodrag Dinic <miodrag.dinic@xxxxxxxx>
>
> Add device driver for a virtual programmable interrupt controller
>
> The virtual PIC is designed as a device tree-based interrupt controller.
>
> The compatible string used by OS for binding the driver is
> "google,goldfish-pic".
>
> Signed-off-by: Miodrag Dinic <miodrag.dinic@xxxxxxxx>
> Signed-off-by: Goran Ferenc <goran.ferenc@xxxxxxxx>
> Signed-off-by: Aleksandar Markovic <aleksandar.markovic@xxxxxxxx>

[...]

> diff --git a/drivers/irqchip/irq-goldfish-pic.c b/drivers/irqchip/irq-goldfish-pic.c
> new file mode 100644
> index 0000000..48fb773
> --- /dev/null
> +++ b/drivers/irqchip/irq-goldfish-pic.c

[...]

> +static int __init goldfish_pic_of_init(struct device_node *of_node,
> +				       struct device_node *parent)
> +{
> +	struct goldfish_pic_data *gfpic;
> +	struct irq_chip_generic *gc;
> +	struct irq_chip_type *ct;
> +	unsigned int parent_irq;
> +	int ret = 0;
> +
> +	gfpic = kzalloc(sizeof(*gfpic), GFP_KERNEL);
> +	if (!gfpic) {
> +		ret = -ENOMEM;
> +		goto out_err;
> +	}
> +
> +	parent_irq = irq_of_parse_and_map(of_node, 0);
> +	if (!parent_irq) {
> +		pr_err("Failed to map Goldfish PIC parent IRQ\n");
> +		ret = -EINVAL;
> +		goto out_free;
> +	}
> +
> +	gfpic->base = of_iomap(of_node, 0);
> +	if (!gfpic->base) {
> +		pr_err("Failed to map Goldfish PIC base\n");
> +		ret = -ENOMEM;
> +		goto out_unmap_irq;
> +	}
> +
> +	/* Mask interrupts. */
> +	writel(1, gfpic->base + GFPIC_REG_IRQ_DISABLE_ALL);
> +
> +	gc = irq_alloc_generic_chip("GFPIC", 1, GFPIC_IRQ_BASE, gfpic->base,
> +				    handle_level_irq);
> +
> +	ct = gc->chip_types;

And what if the allocation fails?

> +	ct->regs.enable = GFPIC_REG_IRQ_ENABLE;
> +	ct->regs.disable = GFPIC_REG_IRQ_DISABLE;
> +	ct->chip.irq_unmask = irq_gc_unmask_enable_reg;
> +	ct->chip.irq_mask = irq_gc_mask_disable_reg;
> +
> +	irq_setup_generic_chip(gc, IRQ_MSK(GFPIC_NR_IRQS), 0, 0,
> +			       IRQ_NOPROBE | IRQ_LEVEL);
> +
> +	gfpic->irq_domain = irq_domain_add_legacy(of_node, GFPIC_NR_IRQS,
> +						  GFPIC_IRQ_BASE, 0,
> +						  &goldfish_irq_domain_ops,
> +						  NULL);
> +	if (!gfpic->irq_domain) {
> +		pr_err("Failed to add irqdomain for Goldfish PIC\n");
> +		ret = -EINVAL;
> +		goto out_iounmap;
> +	}
> +
> +	irq_set_chained_handler_and_data(parent_irq,
> +					 goldfish_pic_cascade, gfpic);
> +
> +	pr_info("Successfully registered Goldfish PIC\n");
> +	return 0;
> +
> +out_iounmap:
> +	iounmap(gfpic->base);
> +out_unmap_irq:
> +	irq_dispose_mapping(parent_irq); 
> +out_free:
> +	kfree(gfpic);
> +out_err:
> +	return ret;
> +}
> +
> +IRQCHIP_DECLARE(google_gf_pic, "google,goldfish-pic", goldfish_pic_of_init);

Thanks,

	M.
-- 
Jazz is not dead. It just smells funny.