From: Andrew Lunn <andrew@xxxxxxx> When performing a C22 operation, check that the bus driver actually provides the methods, and return -EOPNOTSUPP if not. C45 only busses do exist, and in future their C22 methods will be NULL. Signed-off-by: Andrew Lunn <andrew@xxxxxxx> Signed-off-by: Michael Walle <michael@xxxxxxxx> --- drivers/net/phy/mdio_bus.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/net/phy/mdio_bus.c b/drivers/net/phy/mdio_bus.c index d14d7704e895..20ba38a346fe 100644 --- a/drivers/net/phy/mdio_bus.c +++ b/drivers/net/phy/mdio_bus.c @@ -769,7 +769,10 @@ int __mdiobus_read(struct mii_bus *bus, int addr, u32 regnum) lockdep_assert_held_once(&bus->mdio_lock); - retval = bus->read(bus, addr, regnum); + if (bus->read) + retval = bus->read(bus, addr, regnum); + else + retval = -EOPNOTSUPP; trace_mdio_access(bus, 1, addr, regnum, retval, retval); mdiobus_stats_acct(&bus->stats[addr], true, retval); @@ -795,7 +798,10 @@ int __mdiobus_write(struct mii_bus *bus, int addr, u32 regnum, u16 val) lockdep_assert_held_once(&bus->mdio_lock); - err = bus->write(bus, addr, regnum, val); + if (bus->write) + err = bus->write(bus, addr, regnum, val); + else + err = -EOPNOTSUPP; trace_mdio_access(bus, 0, addr, regnum, val, err); mdiobus_stats_acct(&bus->stats[addr], false, err); -- 2.30.2
