PCI: kirin: Add dev struct for of_device_get_match_data()

Bean reported that a622435 ("PCI: kirin: Prefer
of_device_get_match_data()") broke kirin_pcie_probe() because it assumed
match data of 0 was a failure when in fact, it meant the match data was
"(void *)PCIE_KIRIN_INTERNAL_PHY".

Therefore, probing of "hisilicon,kirin960-pcie" devices failed with -EINVAL
and an "OF data missing" message.

Add a struct kirin_pcie_data to encode the PHY type.  Then the result of
of_device_get_match_data() should always be a non-NULL pointer to a struct
kirin_pcie_data that contains the PHY type.

Fixes: a622435 ("PCI: kirin: Prefer of_device_get_match_data()")
Link: https://lore.kernel.org/r/20220202162659.GA12603@bhelgaas
Link: https://lore.kernel.org/r/20220201215941.1203155-1-huobean@gmail.com
Reported-by: Bean Huo <beanhuo@micron.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

Author: bjorn-helgaas

drivers/pci/controller/dwc/pcie-kirin.c

@@ -756,22 +756,28 @@ static int __exit kirin_pcie_remove(struct platform_device *pdev)
 	return 0;
 }
 
+struct kirin_pcie_data {
+	enum pcie_kirin_phy_type	phy_type;
+};
+
+static const struct kirin_pcie_data kirin_960_data = {
+	.phy_type = PCIE_KIRIN_INTERNAL_PHY,
+};
+
+static const struct kirin_pcie_data kirin_970_data = {
+	.phy_type = PCIE_KIRIN_EXTERNAL_PHY,
+};
+
 static const struct of_device_id kirin_pcie_match[] = {
-	{
-		.compatible = "hisilicon,kirin960-pcie",
-		.data = (void *)PCIE_KIRIN_INTERNAL_PHY
-	},
-	{
-		.compatible = "hisilicon,kirin970-pcie",
-		.data = (void *)PCIE_KIRIN_EXTERNAL_PHY
-	},
+	{ .compatible = "hisilicon,kirin960-pcie", .data = &kirin_960_data },
+	{ .compatible = "hisilicon,kirin970-pcie", .data = &kirin_970_data },
 	{},
 };
 
 static int kirin_pcie_probe(struct platform_device *pdev)
 {
-	enum pcie_kirin_phy_type phy_type;
 	struct device *dev = &pdev->dev;
+	const struct kirin_pcie_data *data;
 	struct kirin_pcie *kirin_pcie;
 	struct dw_pcie *pci;
 	int ret;
@@ -781,13 +787,12 @@ static int kirin_pcie_probe(struct platform_device *pdev)
 		return -EINVAL;
 	}
 
-	phy_type = (long)of_device_get_match_data(dev);
-	if (!phy_type) {
+	data = of_device_get_match_data(dev);
+	if (!data) {
 		dev_err(dev, "OF data missing\n");
 		return -EINVAL;
 	}
 
-
 	kirin_pcie = devm_kzalloc(dev, sizeof(struct kirin_pcie), GFP_KERNEL);
 	if (!kirin_pcie)
 		return -ENOMEM;
@@ -800,7 +805,7 @@ static int kirin_pcie_probe(struct platform_device *pdev)
 	pci->ops = &kirin_dw_pcie_ops;
 	pci->pp.ops = &kirin_pcie_host_ops;
 	kirin_pcie->pci = pci;
-	kirin_pcie->type = phy_type;
+	kirin_pcie->type = data->phy_type;
 
 	ret = kirin_pcie_get_resource(kirin_pcie, pdev);
 	if (ret)