net: ethernet: mediatek: use devm_mdiobus_alloc instead of mdiobus_alloc inside mtk_m...

a lot of parts in the driver uses devm_* APIs to gain benefits from the
device resource management, so devm_mdiobus_alloc is also used instead
of mdiobus_alloc to have more elegant code flow.

Using common code provided by the devm_* helps to
1) have simplified the code flow as [1] says
2) decrease the risk of incorrect error handling by human
3) only a few drivers used it since it was proposed on linux 3.16,
so just hope to promote for this.

Ref:
[1] https://patchwork.ozlabs.org/patch/344093/

Signed-off-by: Sean Wang <sean.wang@mediatek.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.c b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
index 409efcf..0367f51 100644 (file)
--- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c
+++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
@@ -295,7 +295,7 @@ err_phy:
 static int mtk_mdio_init(struct mtk_eth *eth)
 {
        struct device_node *mii_np;
-       int err;
+       int ret;
 
        mii_np = of_get_child_by_name(eth->dev->of_node, "mdio-bus");
        if (!mii_np) {
@@ -304,13 +304,13 @@ static int mtk_mdio_init(struct mtk_eth *eth)
        }
 
        if (!of_device_is_available(mii_np)) {
-               err = 0;
+               ret = 0;
                goto err_put_node;
        }
 
-       eth->mii_bus = mdiobus_alloc();
+       eth->mii_bus = devm_mdiobus_alloc(eth->dev);
        if (!eth->mii_bus) {
-               err = -ENOMEM;
+               ret = -ENOMEM;
                goto err_put_node;
        }
 
@@ -321,20 +321,11 @@ static int mtk_mdio_init(struct mtk_eth *eth)
        eth->mii_bus->parent = eth->dev;
 
        snprintf(eth->mii_bus->id, MII_BUS_ID_SIZE, "%s", mii_np->name);
-       err = of_mdiobus_register(eth->mii_bus, mii_np);
-       if (err)
-               goto err_free_bus;
-       of_node_put(mii_np);
-
-       return 0;
-
-err_free_bus:
-       mdiobus_free(eth->mii_bus);
+       ret = of_mdiobus_register(eth->mii_bus, mii_np);
 
 err_put_node:
        of_node_put(mii_np);
-       eth->mii_bus = NULL;
-       return err;
+       return ret;
 }
 
 static void mtk_mdio_cleanup(struct mtk_eth *eth)
@@ -343,8 +334,6 @@ static void mtk_mdio_cleanup(struct mtk_eth *eth)
                return;
 
        mdiobus_unregister(eth->mii_bus);
-       of_node_put(eth->mii_bus->dev.of_node);
-       mdiobus_free(eth->mii_bus);
 }
 
 static inline void mtk_irq_disable(struct mtk_eth *eth, u32 mask)