PCI: tegra: Use helper function for_each_child_of_node_scoped()

The for_each_available_child_of_node_scoped() helper provides
a scope-based clean-up functionality to put the device_node
automatically, and as such, there is no need to call of_node_put()
directly.

Thus, use this helper to simplify the code.

Signed-off-by: Zhang Zekun <zhangzekun11@huawei.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20240831040413.126417-7-zhangzekun11@huawei.com
[kwilczynski: commit log]
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>

Author: Zhang Zekun

drivers/pci/controller/pci-tegra.c

@@ -2106,47 +2106,39 @@ static int tegra_pcie_get_regulators(struct tegra_pcie *pcie, u32 lane_mask)
 static int tegra_pcie_parse_dt(struct tegra_pcie *pcie)
 {
 	struct device *dev = pcie->dev;
-	struct device_node *np = dev->of_node, *port;
+	struct device_node *np = dev->of_node;
 	const struct tegra_pcie_soc *soc = pcie->soc;
 	u32 lanes = 0, mask = 0;
 	unsigned int lane = 0;
 	int err;
 
 	/* parse root ports */
-	for_each_child_of_node(np, port) {
+	for_each_child_of_node_scoped(np, port) {
 		struct tegra_pcie_port *rp;
 		unsigned int index;
 		u32 value;
 		char *label;
 
 		err = of_pci_get_devfn(port);
-		if (err < 0) {
-			dev_err(dev, "failed to parse address: %d\n", err);
-			goto err_node_put;
-		}
+		if (err < 0)
+			return dev_err_probe(dev, err, "failed to parse address\n");
 
 		index = PCI_SLOT(err);
 
-		if (index < 1 || index > soc->num_ports) {
-			dev_err(dev, "invalid port number: %d\n", index);
-			err = -EINVAL;
-			goto err_node_put;
-		}
+		if (index < 1 || index > soc->num_ports)
+			return dev_err_probe(dev, -EINVAL,
+					     "invalid port number: %d\n", index);
 
 		index--;
 
 		err = of_property_read_u32(port, "nvidia,num-lanes", &value);
-		if (err < 0) {
-			dev_err(dev, "failed to parse # of lanes: %d\n",
-				err);
-			goto err_node_put;
-		}
+		if (err < 0)
+			return dev_err_probe(dev, err,
+					     "failed to parse # of lanes\n");
 
-		if (value > 16) {
-			dev_err(dev, "invalid # of lanes: %u\n", value);
-			err = -EINVAL;
-			goto err_node_put;
-		}
+		if (value > 16)
+			return dev_err_probe(dev, -EINVAL,
+					     "invalid # of lanes: %u\n", value);
 
 		lanes |= value << (index << 3);
 
@@ -2159,16 +2151,12 @@ static int tegra_pcie_parse_dt(struct tegra_pcie *pcie)
 		lane += value;
 
 		rp = devm_kzalloc(dev, sizeof(*rp), GFP_KERNEL);
-		if (!rp) {
-			err = -ENOMEM;
-			goto err_node_put;
-		}
+		if (!rp)
+			return -ENOMEM;
 
 		err = of_address_to_resource(port, 0, &rp->regs);
-		if (err < 0) {
-			dev_err(dev, "failed to parse address: %d\n", err);
-			goto err_node_put;
-		}
+		if (err < 0)
+			return dev_err_probe(dev, err, "failed to parse address\n");
 
 		INIT_LIST_HEAD(&rp->list);
 		rp->index = index;
@@ -2177,16 +2165,12 @@ static int tegra_pcie_parse_dt(struct tegra_pcie *pcie)
 		rp->np = port;
 
 		rp->base = devm_pci_remap_cfg_resource(dev, &rp->regs);
-		if (IS_ERR(rp->base)) {
-			err = PTR_ERR(rp->base);
-			goto err_node_put;
-		}
+		if (IS_ERR(rp->base))
+			return PTR_ERR(rp->base);
 
 		label = devm_kasprintf(dev, GFP_KERNEL, "pex-reset-%u", index);
-		if (!label) {
-			err = -ENOMEM;
-			goto err_node_put;
-		}
+		if (!label)
+			return -ENOMEM;
 
 		/*
 		 * Returns -ENOENT if reset-gpios property is not populated
@@ -2199,34 +2183,26 @@ static int tegra_pcie_parse_dt(struct tegra_pcie *pcie)
 						       GPIOD_OUT_LOW,
 						       label);
 		if (IS_ERR(rp->reset_gpio)) {
-			if (PTR_ERR(rp->reset_gpio) == -ENOENT) {
+			if (PTR_ERR(rp->reset_gpio) == -ENOENT)
 				rp->reset_gpio = NULL;
-			} else {
-				dev_err(dev, "failed to get reset GPIO: %ld\n",
-					PTR_ERR(rp->reset_gpio));
-				err = PTR_ERR(rp->reset_gpio);
-				goto err_node_put;
-			}
+			else
+				return dev_err_probe(dev, PTR_ERR(rp->reset_gpio),
+						     "failed to get reset GPIO\n");
 		}
 
 		list_add_tail(&rp->list, &pcie->ports);
 	}
 
 	err = tegra_pcie_get_xbar_config(pcie, lanes, &pcie->xbar_config);
-	if (err < 0) {
-		dev_err(dev, "invalid lane configuration\n");
-		return err;
-	}
+	if (err < 0)
+		return dev_err_probe(dev, err,
+				     "invalid lane configuration\n");
 
 	err = tegra_pcie_get_regulators(pcie, mask);
 	if (err < 0)
 		return err;
 
 	return 0;
-
-err_node_put:
-	of_node_put(port);
-	return err;
 }
 
 /*