[PATCH 5.3 042/197] net: ag71xx: fix mdio subnode support

From: Greg Kroah-Hartman
Date: Sun Oct 27 2019 - 17:20:40 EST

From: Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx>

[ Upstream commit 569aad4fcd82cba64eb10ede235d330a00f0aa09 ]

This patch is syncing driver with actual devicetree documentation:
|Optional subnodes:
|- mdio : specifies the mdio bus, used as a container for phy nodes
| according to phy.txt in the same directory

The driver was working with fixed phy without any noticeable issues. This bug
was uncovered by introducing dsa ar9331-switch driver.
Since no one reported this bug until now, I assume no body is using it
and this patch should not brake existing system.

Fixes: d51b6ce441d3 ("net: ethernet: add ag71xx driver")
Signed-off-by: Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx>
Reviewed-by: Andrew Lunn <andrew@xxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
drivers/net/ethernet/atheros/ag71xx.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/atheros/ag71xx.c b/drivers/net/ethernet/atheros/ag71xx.c
index 6703960c7cf50..d1101eea15c2a 100644
--- a/drivers/net/ethernet/atheros/ag71xx.c
+++ b/drivers/net/ethernet/atheros/ag71xx.c
@@ -526,7 +526,7 @@ static int ag71xx_mdio_probe(struct ag71xx *ag)
struct device *dev = &ag->pdev->dev;
struct net_device *ndev = ag->ndev;
static struct mii_bus *mii_bus;
- struct device_node *np;
+ struct device_node *np, *mnp;
int err;

np = dev->of_node;
@@ -571,7 +571,9 @@ static int ag71xx_mdio_probe(struct ag71xx *ag)

- err = of_mdiobus_register(mii_bus, np);
+ mnp = of_get_child_by_name(np, "mdio");
+ err = of_mdiobus_register(mii_bus, mnp);
+ of_node_put(mnp);
if (err)
goto mdio_err_put_clk;