Hi Krzysztof, Thanks for your reply. On 2024-03-09 12:45:06 +0100, Krzysztof Kozlowski wrote: > On 09/03/2024 02:25, Niklas Söderlund wrote: > > The bindings for Renesas Ethernet AVB are from 2015 and contain some > > oddities that are impossible to get right without breaking existing > > bindings. One such thing is that the MDIO bus properties that should be > > its own node are mixed with the node for the IP for Ethernet AVB. > > > > Instead of a separate node for the MDIO bus, > > > > avb: ethernet@e6800000 { > > compatible = "renesas,etheravb-r8a7795", > > "renesas,etheravb-rcar-gen3"; > > reg = <0xe6800000 0x800>, <0xe6a00000 0x10000>; > > > > ... > > > > phy-handle = <&phy0>; > > > > mdio { > > #address-cells = <1>; > > #size-cells = <0>; > > > > phy0: ethernet-phy@0 { > > ... > > }; > > }; > > }; > > > > The Ethernet AVB mix it in one, > > > > avb: ethernet@e6800000 { > > compatible = "renesas,etheravb-r8a7795", > > "renesas,etheravb-rcar-gen3"; > > reg = <0xe6800000 0x800>, <0xe6a00000 0x10000>; > > > > ... > > > > phy-handle = <&phy0>; > > > > #address-cells = <1>; > > #size-cells = <0>; > > > > phy0: ethernet-phy@0 { > > ... > > }; > > }; > > > > This forces to all MDIO bus properties needed to be described in the > > Ethernet AVB bindings directly. However not all MDIO bus properties are > > described as they were not needed. This change adds the MDIO bus > > properties to reset the MDIO bus in preparation for them being used. > > That is not exactly what you wrote in the binding. Binding suggests you > have per device GPIO, which in your design is shared but the commit msg > says it is some sort of bus reset. > > These are two different things, because in first case you could have a > design using two GPIOs, not one. Then your binding is completely wrong. I copied the description from mdio.yaml as the intention is the two are the same. But on a second read I agree it's confusing. > > Plus, where is the user of all this? I think you found it in, for posterity it's in '[PATCH] arm64: dts: renesas: white-hawk: ethernet: Describe adv1 and avb2'. > > I think you should rather correct the binding to use mdio node and add > appropriate handling in the driver, keeping backward compatibility. I had not consider that, the driver can indeed support both modes and only allow MDIO bus properties if the mdio sub-node is present. I will do so, thanks for the suggestion. -- Kind Regards, Niklas Söderlund