static int __init sun5i_setup_clocksource()

in timer-sun5i.c [186:247]

• 52 lines of code
• 6 McCabe index (conditional complexity)

static int __init sun5i_setup_clocksource(struct device_node *node,
					  void __iomem *base,
					  struct clk *clk, int irq)
{
	struct sun5i_timer_clksrc *cs;
	unsigned long rate;
	int ret;

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

	ret = clk_prepare_enable(clk);
	if (ret) {
		pr_err("Couldn't enable parent clock\n");
		goto err_free;
	}

	rate = clk_get_rate(clk);
	if (!rate) {
		pr_err("Couldn't get parent clock rate\n");
		ret = -EINVAL;
		goto err_disable_clk;
	}

	cs->timer.base = base;
	cs->timer.clk = clk;
	cs->timer.clk_rate_cb.notifier_call = sun5i_rate_cb_clksrc;
	cs->timer.clk_rate_cb.next = NULL;

	ret = clk_notifier_register(clk, &cs->timer.clk_rate_cb);
	if (ret) {
		pr_err("Unable to register clock notifier.\n");
		goto err_disable_clk;
	}

	writel(~0, base + TIMER_INTVAL_LO_REG(1));
	writel(TIMER_CTL_ENABLE | TIMER_CTL_RELOAD,
	       base + TIMER_CTL_REG(1));

	cs->clksrc.name = node->name;
	cs->clksrc.rating = 340;
	cs->clksrc.read = sun5i_clksrc_read;
	cs->clksrc.mask = CLOCKSOURCE_MASK(32);
	cs->clksrc.flags = CLOCK_SOURCE_IS_CONTINUOUS;

	ret = clocksource_register_hz(&cs->clksrc, rate);
	if (ret) {
		pr_err("Couldn't register clock source.\n");
		goto err_remove_notifier;
	}

	return 0;

err_remove_notifier:
	clk_notifier_unregister(clk, &cs->timer.clk_rate_cb);
err_disable_clk:
	clk_disable_unprepare(clk);
err_free:
	kfree(cs);
	return ret;
}