static int __init zevio_timer_add()

in timer-zevio.c [116:206]

• 73 lines of code
• 7 McCabe index (conditional complexity)

static int __init zevio_timer_add(struct device_node *node)
{
	struct zevio_timer *timer;
	struct resource res;
	int irqnr, ret;

	timer = kzalloc(sizeof(*timer), GFP_KERNEL);
	if (!timer)
		return -ENOMEM;

	timer->base = of_iomap(node, 0);
	if (!timer->base) {
		ret = -EINVAL;
		goto error_free;
	}
	timer->timer1 = timer->base + IO_TIMER1;
	timer->timer2 = timer->base + IO_TIMER2;

	timer->clk = of_clk_get(node, 0);
	if (IS_ERR(timer->clk)) {
		ret = PTR_ERR(timer->clk);
		pr_err("Timer clock not found! (error %d)\n", ret);
		goto error_unmap;
	}

	timer->interrupt_regs = of_iomap(node, 1);
	irqnr = irq_of_parse_and_map(node, 0);

	of_address_to_resource(node, 0, &res);
	scnprintf(timer->clocksource_name, sizeof(timer->clocksource_name),
			"%llx.%pOFn_clocksource",
			(unsigned long long)res.start, node);

	scnprintf(timer->clockevent_name, sizeof(timer->clockevent_name),
			"%llx.%pOFn_clockevent",
			(unsigned long long)res.start, node);

	if (timer->interrupt_regs && irqnr) {
		timer->clkevt.name		= timer->clockevent_name;
		timer->clkevt.set_next_event	= zevio_timer_set_event;
		timer->clkevt.set_state_shutdown = zevio_timer_shutdown;
		timer->clkevt.set_state_oneshot = zevio_timer_set_oneshot;
		timer->clkevt.tick_resume	= zevio_timer_set_oneshot;
		timer->clkevt.rating		= 200;
		timer->clkevt.cpumask		= cpu_possible_mask;
		timer->clkevt.features		= CLOCK_EVT_FEAT_ONESHOT;
		timer->clkevt.irq		= irqnr;

		writel(CNTL_STOP_TIMER, timer->timer1 + IO_CONTROL);
		writel(0, timer->timer1 + IO_DIVIDER);

		/* Start with timer interrupts disabled */
		writel(0, timer->interrupt_regs + IO_INTR_MSK);
		writel(TIMER_INTR_ALL, timer->interrupt_regs + IO_INTR_ACK);

		/* Interrupt to occur when timer value matches 0 */
		writel(0, timer->base + IO_MATCH(TIMER_MATCH));

		if (request_irq(irqnr, zevio_timer_interrupt,
				IRQF_TIMER | IRQF_IRQPOLL,
				timer->clockevent_name, timer)) {
			pr_err("%s: request_irq() failed\n",
			       timer->clockevent_name);
		}

		clockevents_config_and_register(&timer->clkevt,
				clk_get_rate(timer->clk), 0x0001, 0xffff);
		pr_info("Added %s as clockevent\n", timer->clockevent_name);
	}

	writel(CNTL_STOP_TIMER, timer->timer2 + IO_CONTROL);
	writel(0, timer->timer2 + IO_CURRENT_VAL);
	writel(0, timer->timer2 + IO_DIVIDER);
	writel(CNTL_RUN_TIMER | CNTL_FOREVER | CNTL_INC,
			timer->timer2 + IO_CONTROL);

	clocksource_mmio_init(timer->timer2 + IO_CURRENT_VAL,
			timer->clocksource_name,
			clk_get_rate(timer->clk),
			200, 16,
			clocksource_mmio_readw_up);

	pr_info("Added %s as clocksource\n", timer->clocksource_name);

	return 0;
error_unmap:
	iounmap(timer->base);
error_free:
	kfree(timer);
	return ret;
}