static int __init sunxi_sc_nmi_irq_init()

in irq-sunxi-nmi.c [146:220]

• 60 lines of code
• 5 McCabe index (conditional complexity)

static int __init sunxi_sc_nmi_irq_init(struct device_node *node,
					const struct sunxi_sc_nmi_reg_offs *reg_offs)
{
	struct irq_domain *domain;
	struct irq_chip_generic *gc;
	unsigned int irq;
	unsigned int clr = IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN;
	int ret;


	domain = irq_domain_add_linear(node, 1, &irq_generic_chip_ops, NULL);
	if (!domain) {
		pr_err("Could not register interrupt domain.\n");
		return -ENOMEM;
	}

	ret = irq_alloc_domain_generic_chips(domain, 1, 2, DRV_NAME,
					     handle_fasteoi_irq, clr, 0,
					     IRQ_GC_INIT_MASK_CACHE);
	if (ret) {
		pr_err("Could not allocate generic interrupt chip.\n");
		goto fail_irqd_remove;
	}

	irq = irq_of_parse_and_map(node, 0);
	if (irq <= 0) {
		pr_err("unable to parse irq\n");
		ret = -EINVAL;
		goto fail_irqd_remove;
	}

	gc = irq_get_domain_generic_chip(domain, 0);
	gc->reg_base = of_io_request_and_map(node, 0, of_node_full_name(node));
	if (IS_ERR(gc->reg_base)) {
		pr_err("unable to map resource\n");
		ret = PTR_ERR(gc->reg_base);
		goto fail_irqd_remove;
	}

	gc->chip_types[0].type			= IRQ_TYPE_LEVEL_MASK;
	gc->chip_types[0].chip.irq_mask		= irq_gc_mask_clr_bit;
	gc->chip_types[0].chip.irq_unmask	= irq_gc_mask_set_bit;
	gc->chip_types[0].chip.irq_eoi		= irq_gc_ack_set_bit;
	gc->chip_types[0].chip.irq_set_type	= sunxi_sc_nmi_set_type;
	gc->chip_types[0].chip.flags		= IRQCHIP_EOI_THREADED | IRQCHIP_EOI_IF_HANDLED;
	gc->chip_types[0].regs.ack		= reg_offs->pend;
	gc->chip_types[0].regs.mask		= reg_offs->enable;
	gc->chip_types[0].regs.type		= reg_offs->ctrl;

	gc->chip_types[1].type			= IRQ_TYPE_EDGE_BOTH;
	gc->chip_types[1].chip.name		= gc->chip_types[0].chip.name;
	gc->chip_types[1].chip.irq_ack		= irq_gc_ack_set_bit;
	gc->chip_types[1].chip.irq_mask		= irq_gc_mask_clr_bit;
	gc->chip_types[1].chip.irq_unmask	= irq_gc_mask_set_bit;
	gc->chip_types[1].chip.irq_set_type	= sunxi_sc_nmi_set_type;
	gc->chip_types[1].regs.ack		= reg_offs->pend;
	gc->chip_types[1].regs.mask		= reg_offs->enable;
	gc->chip_types[1].regs.type		= reg_offs->ctrl;
	gc->chip_types[1].handler		= handle_edge_irq;

	/* Disable any active interrupts */
	sunxi_sc_nmi_write(gc, reg_offs->enable, 0);

	/* Clear any pending NMI interrupts */
	sunxi_sc_nmi_write(gc, reg_offs->pend, SUNXI_NMI_IRQ_BIT);

	irq_set_chained_handler_and_data(irq, sunxi_sc_nmi_handle_irq, domain);

	return 0;

fail_irqd_remove:
	irq_domain_remove(domain);

	return ret;
}