static int __genpd_dev_pm_attach()

in power/domain.c [2647:2714]

• 57 lines of code
• 12 McCabe index (conditional complexity)

static int __genpd_dev_pm_attach(struct device *dev, struct device *base_dev,
				 unsigned int index, bool power_on)
{
	struct of_phandle_args pd_args;
	struct generic_pm_domain *pd;
	int pstate;
	int ret;

	ret = of_parse_phandle_with_args(dev->of_node, "power-domains",
				"#power-domain-cells", index, &pd_args);
	if (ret < 0)
		return ret;

	mutex_lock(&gpd_list_lock);
	pd = genpd_get_from_provider(&pd_args);
	of_node_put(pd_args.np);
	if (IS_ERR(pd)) {
		mutex_unlock(&gpd_list_lock);
		dev_dbg(dev, "%s() failed to find PM domain: %ld\n",
			__func__, PTR_ERR(pd));
		return driver_deferred_probe_check_state(base_dev);
	}

	dev_dbg(dev, "adding to PM domain %s\n", pd->name);

	ret = genpd_add_device(pd, dev, base_dev);
	mutex_unlock(&gpd_list_lock);

	if (ret < 0) {
		if (ret != -EPROBE_DEFER)
			dev_err(dev, "failed to add to PM domain %s: %d",
				pd->name, ret);
		return ret;
	}

	dev->pm_domain->detach = genpd_dev_pm_detach;
	dev->pm_domain->sync = genpd_dev_pm_sync;

	if (power_on) {
		genpd_lock(pd);
		ret = genpd_power_on(pd, 0);
		genpd_unlock(pd);
	}

	if (ret) {
		genpd_remove_device(pd, dev);
		return -EPROBE_DEFER;
	}

	/* Set the default performance state */
	pstate = of_get_required_opp_performance_state(dev->of_node, index);
	if (pstate < 0 && pstate != -ENODEV && pstate != -EOPNOTSUPP) {
		ret = pstate;
		goto err;
	} else if (pstate > 0) {
		ret = dev_pm_genpd_set_performance_state(dev, pstate);
		if (ret)
			goto err;
		dev_gpd_data(dev)->default_pstate = pstate;
	}
	return 1;

err:
	dev_err(dev, "failed to set required performance state for power-domain %s: %d\n",
		pd->name, ret);
	genpd_remove_device(pd, dev);
	return ret;
}