static int arm_smmu_device_probe()

in arm/arm-smmu-v3/arm-smmu-v3.c [3755:3864]

• 80 lines of code
• 18 McCabe index (conditional complexity)

static int arm_smmu_device_probe(struct platform_device *pdev)
{
	int irq, ret;
	struct resource *res;
	resource_size_t ioaddr;
	struct arm_smmu_device *smmu;
	struct device *dev = &pdev->dev;
	bool bypass;

	smmu = devm_kzalloc(dev, sizeof(*smmu), GFP_KERNEL);
	if (!smmu)
		return -ENOMEM;
	smmu->dev = dev;

	if (dev->of_node) {
		ret = arm_smmu_device_dt_probe(pdev, smmu);
	} else {
		ret = arm_smmu_device_acpi_probe(pdev, smmu);
		if (ret == -ENODEV)
			return ret;
	}

	/* Set bypass mode according to firmware probing result */
	bypass = !!ret;

	/* Base address */
	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (resource_size(res) < arm_smmu_resource_size(smmu)) {
		dev_err(dev, "MMIO region too small (%pr)\n", res);
		return -EINVAL;
	}
	ioaddr = res->start;

	/*
	 * Don't map the IMPLEMENTATION DEFINED regions, since they may contain
	 * the PMCG registers which are reserved by the PMU driver.
	 */
	smmu->base = arm_smmu_ioremap(dev, ioaddr, ARM_SMMU_REG_SZ);
	if (IS_ERR(smmu->base))
		return PTR_ERR(smmu->base);

	if (arm_smmu_resource_size(smmu) > SZ_64K) {
		smmu->page1 = arm_smmu_ioremap(dev, ioaddr + SZ_64K,
					       ARM_SMMU_REG_SZ);
		if (IS_ERR(smmu->page1))
			return PTR_ERR(smmu->page1);
	} else {
		smmu->page1 = smmu->base;
	}

	/* Interrupt lines */

	irq = platform_get_irq_byname_optional(pdev, "combined");
	if (irq > 0)
		smmu->combined_irq = irq;
	else {
		irq = platform_get_irq_byname_optional(pdev, "eventq");
		if (irq > 0)
			smmu->evtq.q.irq = irq;

		irq = platform_get_irq_byname_optional(pdev, "priq");
		if (irq > 0)
			smmu->priq.q.irq = irq;

		irq = platform_get_irq_byname_optional(pdev, "gerror");
		if (irq > 0)
			smmu->gerr_irq = irq;
	}
	/* Probe the h/w */
	ret = arm_smmu_device_hw_probe(smmu);
	if (ret)
		return ret;

	/* Initialise in-memory data structures */
	ret = arm_smmu_init_structures(smmu);
	if (ret)
		return ret;

	/* Record our private device structure */
	platform_set_drvdata(pdev, smmu);

	/* Reset the device */
	ret = arm_smmu_device_reset(smmu, bypass);
	if (ret)
		return ret;

	/* And we're up. Go go go! */
	ret = iommu_device_sysfs_add(&smmu->iommu, dev, NULL,
				     "smmu3.%pa", &ioaddr);
	if (ret)
		return ret;

	ret = iommu_device_register(&smmu->iommu, &arm_smmu_ops, dev);
	if (ret) {
		dev_err(dev, "Failed to register iommu\n");
		goto err_sysfs_remove;
	}

	ret = arm_smmu_set_bus_ops(&arm_smmu_ops);
	if (ret)
		goto err_unregister_device;

	return 0;

err_unregister_device:
	iommu_device_unregister(&smmu->iommu);
err_sysfs_remove:
	iommu_device_sysfs_remove(&smmu->iommu);
	return ret;
}