static int qcom_cpufreq_hw_cpu_init()

in qcom-cpufreq-hw.c [418:525]

• 90 lines of code
• 15 McCabe index (conditional complexity)

static int qcom_cpufreq_hw_cpu_init(struct cpufreq_policy *policy)
{
	struct platform_device *pdev = cpufreq_get_driver_data();
	struct device *dev = &pdev->dev;
	struct of_phandle_args args;
	struct device_node *cpu_np;
	struct device *cpu_dev;
	struct resource *res;
	void __iomem *base;
	struct qcom_cpufreq_data *data;
	int ret, index;

	cpu_dev = get_cpu_device(policy->cpu);
	if (!cpu_dev) {
		pr_err("%s: failed to get cpu%d device\n", __func__,
		       policy->cpu);
		return -ENODEV;
	}

	cpu_np = of_cpu_device_node_get(policy->cpu);
	if (!cpu_np)
		return -EINVAL;

	ret = of_parse_phandle_with_args(cpu_np, "qcom,freq-domain",
					 "#freq-domain-cells", 0, &args);
	of_node_put(cpu_np);
	if (ret)
		return ret;

	index = args.args[0];

	res = platform_get_resource(pdev, IORESOURCE_MEM, index);
	if (!res) {
		dev_err(dev, "failed to get mem resource %d\n", index);
		return -ENODEV;
	}

	if (!request_mem_region(res->start, resource_size(res), res->name)) {
		dev_err(dev, "failed to request resource %pR\n", res);
		return -EBUSY;
	}

	base = ioremap(res->start, resource_size(res));
	if (!base) {
		dev_err(dev, "failed to map resource %pR\n", res);
		ret = -ENOMEM;
		goto release_region;
	}

	data = kzalloc(sizeof(*data), GFP_KERNEL);
	if (!data) {
		ret = -ENOMEM;
		goto unmap_base;
	}

	data->soc_data = of_device_get_match_data(&pdev->dev);
	data->base = base;
	data->res = res;

	/* HW should be in enabled state to proceed */
	if (!(readl_relaxed(base + data->soc_data->reg_enable) & 0x1)) {
		dev_err(dev, "Domain-%d cpufreq hardware not enabled\n", index);
		ret = -ENODEV;
		goto error;
	}

	qcom_get_related_cpus(index, policy->cpus);
	if (!cpumask_weight(policy->cpus)) {
		dev_err(dev, "Domain-%d failed to get related CPUs\n", index);
		ret = -ENOENT;
		goto error;
	}

	policy->driver_data = data;
	policy->dvfs_possible_from_any_cpu = true;

	ret = qcom_cpufreq_hw_read_lut(cpu_dev, policy);
	if (ret) {
		dev_err(dev, "Domain-%d failed to read LUT\n", index);
		goto error;
	}

	ret = dev_pm_opp_get_opp_count(cpu_dev);
	if (ret <= 0) {
		dev_err(cpu_dev, "Failed to add OPPs\n");
		ret = -ENODEV;
		goto error;
	}

	if (policy_has_boost_freq(policy)) {
		ret = cpufreq_enable_boost_support();
		if (ret)
			dev_warn(cpu_dev, "failed to enable boost: %d\n", ret);
	}

	ret = qcom_cpufreq_hw_lmh_init(policy, index);
	if (ret)
		goto error;

	return 0;
error:
	kfree(data);
unmap_base:
	iounmap(base);
release_region:
	release_mem_region(res->start, resource_size(res));
	return ret;
}