PCI: mediatek: Use PCI domain to handle ports detection

Use of_get_pci_domain_nr() to get the pci domain.

If the "linux,pci-domain" property is present, we assume that the PCIe
bridge is an individual bridge, hence we only need to parse one port.

Link: https://lore.kernel.org/r/20210823032800.1660-5-chuanjia.liu@mediatek.com
Signed-off-by: Chuanjia Liu <chuanjia.liu@mediatek.com>
[lorenzo.pieralisi@arm.com: commit log]
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Ryder Lee <ryder.lee@mediatek.com>

1 files changed, 17 insertions, 12 deletions

diff --git a/drivers/pci/controller/pcie-mediatek.c b/drivers/pci/controller/pcie-mediatek.c
index 19e35ac62d43..928e0983a900 100644
--- a/drivers/pci/controller/pcie-mediatek.c
+++ b/drivers/pci/controller/pcie-mediatek.c
@@ -1048,22 +1048,27 @@ static int mtk_pcie_setup(struct mtk_pcie *pcie)
 	struct device *dev = pcie->dev;
 	struct device_node *node = dev->of_node, *child;
 	struct mtk_pcie_port *port, *tmp;
-	int err;
+	int err, slot;
+
+	slot = of_get_pci_domain_nr(dev->of_node);
+	if (slot < 0) {
+		for_each_available_child_of_node(node, child) {
+			err = of_pci_get_devfn(child);
+			if (err < 0) {
+				dev_err(dev, "failed to get devfn: %d\n", err);
+				goto error_put_node;
+			}
 
-	for_each_available_child_of_node(node, child) {
-		int slot;
+			slot = PCI_SLOT(err);
 
-		err = of_pci_get_devfn(child);
-		if (err < 0) {
-			dev_err(dev, "failed to parse devfn: %d\n", err);
-			goto error_put_node;
+			err = mtk_pcie_parse_port(pcie, child, slot);
+			if (err)
+				goto error_put_node;
 		}
-
-		slot = PCI_SLOT(err);
-
-		err = mtk_pcie_parse_port(pcie, child, slot);
+	} else {
+		err = mtk_pcie_parse_port(pcie, node, slot);
 		if (err)
-			goto error_put_node;
+			return err;
 	}
 
 	err = mtk_pcie_subsys_powerup(pcie);