On Fri, Apr 23, 2021 at 10:22:06AM +0200, Linus Walleij wrote: > This adds device tree bindings for the IXP4xx ethernet > controller with optional MDIO bridge. Hi Linus That optional MDIO bus sentence is important here. I think it would be good to give examples for say IXP43x, where the MDIO bus is on NPE-C, and the phy-handles point from one Ethernet device in the device tree to the other. It is not unknown, but it is unusual, so giving an example is good. Also, looking at the unmodified driver, there is the global variable mdio_bus. This should contain the one MDIO bus for the cluster. With the C code, it should be impossible for multiple devices to instantiate an MDIO bus. But with device tree, is that still true? Should there be validation that only one device has an MDIO bus in its device tree? Andrew