[PATCH AUTOSEL for 4.14 069/100] net: dsa: mv88e6xxx: Unregister MDIO bus on error path

Sasha Levin
2018-01-28T23:03:24Z

From: Andrew Lunn <andrew@lunn.ch>

[ Upstream commit 3126aeec5313565bfa19e2dd8fd7e3c3390514cb ]

The MDIO busses need to be unregistered before they are freed,
otherwise BUG() is called. Add a call to the unregister code if the
registration fails, since we can have multiple busses, of which some
may correctly register before one fails. This requires moving the code
around a little.

Fixes: a3c53be55c95 ("net: dsa: mv88e6xxx: Support multiple MDIO busses")
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
---
drivers/net/dsa/mv88e6xxx/chip.c | 30 ++++++++++++++++--------------
1 file changed, 16 insertions(+), 14 deletions(-)

diff --git a/drivers/net/dsa/mv88e6xxx/chip.c b/drivers/net/dsa/mv88e6xxx/chip.c
index 07704b372861..eebda5ec9676 100644
--- a/drivers/net/dsa/mv88e6xxx/chip.c
+++ b/drivers/net/dsa/mv88e6xxx/chip.c
@@ -2153,6 +2153,19 @@ static const struct of_device_id mv88e6xxx_mdio_external_match[] = {
{ },
};

+static void mv88e6xxx_mdios_unregister(struct mv88e6xxx_chip *chip)
+
+{
+ struct mv88e6xxx_mdio_bus *mdio_bus;
+ struct mii_bus *bus;
+
+ list_for_each_entry(mdio_bus, &chip->mdios, list) {
+ bus = mdio_bus->bus;
+
+ mdiobus_unregister(bus);
+ }
+}
+
static int mv88e6xxx_mdios_register(struct mv88e6xxx_chip *chip,
struct device_node *np)
{
@@ -2177,27 +2190,16 @@ static int mv88e6xxx_mdios_register(struct mv88e6xxx_chip *chip,
match = of_match_node(mv88e6xxx_mdio_external_match, child);
if (match) {
err = mv88e6xxx_mdio_register(chip, child, true);
- if (err)
+ if (err) {
+ mv88e6xxx_mdios_unregister(chip);
return err;
+ }
}
}

return 0;
}

-static void mv88e6xxx_mdios_unregister(struct mv88e6xxx_chip *chip)
-
-{
- struct mv88e6xxx_mdio_bus *mdio_bus;
- struct mii_bus *bus;
-
- list_for_each_entry(mdio_bus, &chip->mdios, list) {
- bus = mdio_bus->bus;
-
- mdiobus_unregister(bus);
- }
-}
-
static int mv88e6xxx_get_eeprom_len(struct dsa_switch *ds)
{
struct mv88e6xxx_chip *chip = ds->priv;
--
2.11.0