stmmac: dwmac-loongson: Make sure MDIO is initialized before use

[ Upstream commit e87d3a1370ce9f04770d789bcf7cce44865d2e8d ]

Generic code will use mdio. If it is not initialized before use,
the kernel will Oops.

Fixes: 30bba69d7db4 ("stmmac: pci: Add dwmac support for Loongson")
Signed-off-by: Yanteng Si <siyanteng@loongson.cn>
Signed-off-by: Feiyang Chen <chenfeiyang@loongson.cn>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-loongson.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-loongson.c
index 2cd6fce..e770132 100644 (file)
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac-loongson.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-loongson.c
@@ -68,17 +68,15 @@ static int loongson_dwmac_probe(struct pci_dev *pdev, const struct pci_device_id
        if (!plat)
                return -ENOMEM;
 
+       plat->mdio_bus_data = devm_kzalloc(&pdev->dev,
+                                          sizeof(*plat->mdio_bus_data),
+                                          GFP_KERNEL);
+       if (!plat->mdio_bus_data)
+               return -ENOMEM;
+
        plat->mdio_node = of_get_child_by_name(np, "mdio");
        if (plat->mdio_node) {
                dev_info(&pdev->dev, "Found MDIO subnode\n");
-
-               plat->mdio_bus_data = devm_kzalloc(&pdev->dev,
-                                                  sizeof(*plat->mdio_bus_data),
-                                                  GFP_KERNEL);
-               if (!plat->mdio_bus_data) {
-                       ret = -ENOMEM;
-                       goto err_put_node;
-               }
                plat->mdio_bus_data->needs_reset = true;
        }