Hi Corentin

+Required properties for the mdio-mux node:
+  - compatible = "mdio-mux"

This is too generic. Please add a more specific compatible for this
particular mux. You can keep "mdio-mux", since that is what the MDIO
subsystem will look for.

+Required properties of the integrated phy node:
 - clocks: a phandle to the reference clock for the EPHY
 - resets: a phandle to the reset control for the EPHY
+- phy-is-integrated

So the last thing you said is that the mux is not the problem
here. Something else is locking up. Did you discover what?

I really would like phy-is-integrated to go away.

  Andrew