PCI: aardvark: Convert PCI scan API to pci_scan_root_bus_bridge()

The introduction of pci_scan_root_bus_bridge() provides a PCI core API to
scan a PCI root bus backed by an already initialized struct pci_host_bridge
object, which simplifies the bus scan interface and makes the PCI scan root
bus interface easier to generalize as members are added to the struct
pci_host_bridge.

Convert PCI aardvark host code to pci_scan_root_bus_bridge() to improve the
PCI root bus scanning interface.

Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

drivers/pci/host/pci-aardvark.c

@@ -886,12 +886,14 @@ static int advk_pcie_probe(struct platform_device *pdev)
 	struct advk_pcie *pcie;
 	struct resource *res;
 	struct pci_bus *bus, *child;
+	struct pci_host_bridge *bridge;
 	int ret, irq;
 
-	pcie = devm_kzalloc(dev, sizeof(struct advk_pcie), GFP_KERNEL);
-	if (!pcie)
+	bridge = devm_pci_alloc_host_bridge(dev, sizeof(struct advk_pcie));
+	if (!bridge)
 		return -ENOMEM;
 
+	pcie = pci_host_bridge_priv(bridge);
 	pcie->pdev = pdev;
 
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
@@ -929,14 +931,21 @@ static int advk_pcie_probe(struct platform_device *pdev)
 		return ret;
 	}
 
-	bus = pci_scan_root_bus(dev, 0, &advk_pcie_ops,
-				pcie, &pcie->resources);
-	if (!bus) {
+	list_splice_init(&pcie->resources, &bridge->windows);
+	bridge->dev.parent = dev;
+	bridge->sysdata = pcie;
+	bridge->busnr = 0;
+	bridge->ops = &advk_pcie_ops;
+
+	ret = pci_scan_root_bus_bridge(bridge);
+	if (ret < 0) {
 		advk_pcie_remove_msi_irq_domain(pcie);
 		advk_pcie_remove_irq_domain(pcie);
-		return -ENOMEM;
+		return ret;
 	}
 
+	bus = bridge->bus;
+
 	pci_bus_assign_resources(bus);
 
 	list_for_each_entry(child, &bus->children, node)