| Message ID | 20210804214333.927985-4-saravanak@google.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | Clean up and fix error handling in mdio_mux_init() | expand |
On Wed, Aug 04, 2021 at 02:43:32PM -0700, Saravana Kannan wrote: > When registering mdiobus children, if we get an -EPROBE_DEFER, we shouldn't > ignore it and continue registering the rest of the mdiobus children. This > would permanently prevent the deferring child mdiobus from working instead > of reattempting it in the future. So, if a child mdiobus needs to be > reattempted in the future, defer the entire mdio-mux initialization. > > This fixes the issue where PHYs sitting under the mdio-mux aren't > initialized correctly if the PHY's interrupt controller is not yet ready > when the mdio-mux is being probed. Additional context in the link below. > > Link: https://lore.kernel.org/lkml/CAGETcx95kHrv8wA-O+-JtfH7H9biJEGJtijuPVN0V5dUKUAB3A@mail.gmail.com/#t > Signed-off-by: Saravana Kannan <saravanak@google.com> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Andrew
diff --git a/drivers/net/mdio/mdio-mux.c b/drivers/net/mdio/mdio-mux.c index 13035e2685c4..ebd001f0eece 100644 --- a/drivers/net/mdio/mdio-mux.c +++ b/drivers/net/mdio/mdio-mux.c @@ -175,11 +175,15 @@ int mdio_mux_init(struct device *dev, cb->mii_bus->write = mdio_mux_write; r = of_mdiobus_register(cb->mii_bus, child_bus_node); if (r) { + mdiobus_free(cb->mii_bus); + if (r == -EPROBE_DEFER) { + ret_val = r; + goto err_loop; + } + devm_kfree(dev, cb); dev_err(dev, "Error: Failed to register MDIO bus for child %pOF\n", child_bus_node); - mdiobus_free(cb->mii_bus); - devm_kfree(dev, cb); } else { cb->next = pb->children; pb->children = cb;
When registering mdiobus children, if we get an -EPROBE_DEFER, we shouldn't ignore it and continue registering the rest of the mdiobus children. This would permanently prevent the deferring child mdiobus from working instead of reattempting it in the future. So, if a child mdiobus needs to be reattempted in the future, defer the entire mdio-mux initialization. This fixes the issue where PHYs sitting under the mdio-mux aren't initialized correctly if the PHY's interrupt controller is not yet ready when the mdio-mux is being probed. Additional context in the link below. Link: https://lore.kernel.org/lkml/CAGETcx95kHrv8wA-O+-JtfH7H9biJEGJtijuPVN0V5dUKUAB3A@mail.gmail.com/#t Signed-off-by: Saravana Kannan <saravanak@google.com> --- drivers/net/mdio/mdio-mux.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-)