diff options
| author | Vladimir Oltean <vladimir.oltean@nxp.com> | 2023-12-13 17:27:12 +0200 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2023-12-14 18:55:38 -0800 |
| commit | 10ad63da5c036b2fd61600b43217cfa9b4d66f52 (patch) | |
| tree | 7b5786fcc83a53d84185f21795ec90e85362ba00 | |
| parent | d215ab4d6ae8bea8f66a50399745791b7de5b7d8 (diff) | |
net: mdio-mux: be compatible with parent buses which only support C45
After the mii_bus API conversion to a split read() / read_c45(), there
might be MDIO parent buses which only populate the read_c45() and
write_c45() function pointers but not the C22 variants.
We haven't seen these in the wild paired with MDIO multiplexers, but
Andrew points out we should treat the corner case.
Link: https://lore.kernel.org/netdev/4ccd7dc9-b611-48aa-865f-68d3a1327ce8@lunn.ch/
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://lore.kernel.org/r/20231213152712.320842-3-vladimir.oltean@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
| -rw-r--r-- | drivers/net/mdio/mdio-mux.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/drivers/net/mdio/mdio-mux.c b/drivers/net/mdio/mdio-mux.c index e5dee7ad7c09..fe0e46bd7964 100644 --- a/drivers/net/mdio/mdio-mux.c +++ b/drivers/net/mdio/mdio-mux.c @@ -214,8 +214,10 @@ int mdio_mux_init(struct device *dev, snprintf(cb->mii_bus->id, MII_BUS_ID_SIZE, "%s-%x.%x", cb->mii_bus->name, pb->parent_id, v); cb->mii_bus->parent = dev; - cb->mii_bus->read = mdio_mux_read; - cb->mii_bus->write = mdio_mux_write; + if (parent_bus->read) + cb->mii_bus->read = mdio_mux_read; + if (parent_bus->write) + cb->mii_bus->write = mdio_mux_write; if (parent_bus->read_c45) cb->mii_bus->read_c45 = mdio_mux_read_c45; if (parent_bus->write_c45) |