static int xgene_pmu_probe()

in xgene_pmu.c [1833:1943]

• 87 lines of code
• 14 McCabe index (conditional complexity)

static int xgene_pmu_probe(struct platform_device *pdev)
{
	const struct xgene_pmu_data *dev_data;
	const struct of_device_id *of_id;
	struct xgene_pmu *xgene_pmu;
	struct resource *res;
	int irq, rc;
	int version;

	/* Install a hook to update the reader CPU in case it goes offline */
	rc = cpuhp_setup_state_multi(CPUHP_AP_PERF_ARM_APM_XGENE_ONLINE,
				      "CPUHP_AP_PERF_ARM_APM_XGENE_ONLINE",
				      xgene_pmu_online_cpu,
				      xgene_pmu_offline_cpu);
	if (rc)
		return rc;

	xgene_pmu = devm_kzalloc(&pdev->dev, sizeof(*xgene_pmu), GFP_KERNEL);
	if (!xgene_pmu)
		return -ENOMEM;
	xgene_pmu->dev = &pdev->dev;
	platform_set_drvdata(pdev, xgene_pmu);

	version = -EINVAL;
	of_id = of_match_device(xgene_pmu_of_match, &pdev->dev);
	if (of_id) {
		dev_data = (const struct xgene_pmu_data *) of_id->data;
		version = dev_data->id;
	}

#ifdef CONFIG_ACPI
	if (ACPI_COMPANION(&pdev->dev)) {
		const struct acpi_device_id *acpi_id;

		acpi_id = acpi_match_device(xgene_pmu_acpi_match, &pdev->dev);
		if (acpi_id)
			version = (int) acpi_id->driver_data;
	}
#endif
	if (version < 0)
		return -ENODEV;

	if (version == PCP_PMU_V3)
		xgene_pmu->ops = &xgene_pmu_v3_ops;
	else
		xgene_pmu->ops = &xgene_pmu_ops;

	INIT_LIST_HEAD(&xgene_pmu->l3cpmus);
	INIT_LIST_HEAD(&xgene_pmu->iobpmus);
	INIT_LIST_HEAD(&xgene_pmu->mcbpmus);
	INIT_LIST_HEAD(&xgene_pmu->mcpmus);

	xgene_pmu->version = version;
	dev_info(&pdev->dev, "X-Gene PMU version %d\n", xgene_pmu->version);

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	xgene_pmu->pcppmu_csr = devm_ioremap_resource(&pdev->dev, res);
	if (IS_ERR(xgene_pmu->pcppmu_csr)) {
		dev_err(&pdev->dev, "ioremap failed for PCP PMU resource\n");
		return PTR_ERR(xgene_pmu->pcppmu_csr);
	}

	irq = platform_get_irq(pdev, 0);
	if (irq < 0)
		return -EINVAL;

	rc = devm_request_irq(&pdev->dev, irq, xgene_pmu_isr,
				IRQF_NOBALANCING | IRQF_NO_THREAD,
				dev_name(&pdev->dev), xgene_pmu);
	if (rc) {
		dev_err(&pdev->dev, "Could not request IRQ %d\n", irq);
		return rc;
	}

	xgene_pmu->irq = irq;

	raw_spin_lock_init(&xgene_pmu->lock);

	/* Check for active MCBs and MCUs */
	rc = xgene_pmu_probe_active_mcb_mcu_l3c(xgene_pmu, pdev);
	if (rc) {
		dev_warn(&pdev->dev, "Unknown MCB/MCU active status\n");
		xgene_pmu->mcb_active_mask = 0x1;
		xgene_pmu->mc_active_mask = 0x1;
	}

	/* Add this instance to the list used by the hotplug callback */
	rc = cpuhp_state_add_instance(CPUHP_AP_PERF_ARM_APM_XGENE_ONLINE,
				      &xgene_pmu->node);
	if (rc) {
		dev_err(&pdev->dev, "Error %d registering hotplug", rc);
		return rc;
	}

	/* Walk through the tree for all PMU perf devices */
	rc = xgene_pmu_probe_pmu_dev(xgene_pmu, pdev);
	if (rc) {
		dev_err(&pdev->dev, "No PMU perf devices found!\n");
		goto out_unregister;
	}

	/* Enable interrupt */
	xgene_pmu->ops->unmask_int(xgene_pmu);

	return 0;

out_unregister:
	cpuhp_state_remove_instance(CPUHP_AP_PERF_ARM_APM_XGENE_ONLINE,
				    &xgene_pmu->node);
	return rc;
}