On Tue, Sep 19, 2017 at 09:49:52PM -0500, Rob Herring wrote: > On Thu, Sep 14, 2017 at 2:19 PM, Andrew Lunn <andrew@xxxxxxx> wrote: > >> > Is the MDIO controller "allwinner,sun8i-h3-emac" or "snps,dwmac-mdio"? > >> > If the latter, then I think the node is fine, but then the mux should be > >> > a child node of it. IOW, the child of an MDIO controller should either > >> > be a mux node or slave devices. > > > > Hi Rob > > > > Up until now, children of an MDIO bus have been MDIO devices. Those > > MDIO devices are either Ethernet PHYs, Ethernet Switches, or the > > oddball devices that Broadcom iProc has, like generic PHYs. > > > > We have never had MDIO-muxes as MDIO children. A Mux is not an MDIO > > device, and does not have the properties of an MDIO device. It is not > > addressable on the MDIO bus. The current MUXes are addressed via GPIOs > > or MMIO. > > The DT parent/child relationship defines the bus topology. We describe > MDIO buses in that way and if a mux is sitting between the controller > and the devices, then the DT hierarchy should reflect that. Now > sometimes we have 2 options for what interface has the parent/child > relationship (e.g. an I2C controlled USB hub chip), but in this case > we don't. > Putting mdio-mux as a child of it (the mdio node) give me: [ 18.175338] libphy: stmmac: probed [ 18.175379] mdio_bus stmmac-0: /soc/ethernet@1c30000/mdio/mdio-mux has invalid PHY address [ 18.175408] mdio_bus stmmac-0: scan phy mdio-mux at address 0 [ 18.175450] mdio_bus stmmac-0: scan phy mdio-mux at address 1 [ 18.175482] mdio_bus stmmac-0: scan phy mdio-mux at address 2 [ 18.175513] mdio_bus stmmac-0: scan phy mdio-mux at address 3 [ 18.175544] mdio_bus stmmac-0: scan phy mdio-mux at address 4 [ 18.175575] mdio_bus stmmac-0: scan phy mdio-mux at address 5 [ 18.175607] mdio_bus stmmac-0: scan phy mdio-mux at address 6 [ 18.175638] mdio_bus stmmac-0: scan phy mdio-mux at address 7 [ 18.175669] mdio_bus stmmac-0: scan phy mdio-mux at address 8 [ 18.175700] mdio_bus stmmac-0: scan phy mdio-mux at address 9 [ 18.175731] mdio_bus stmmac-0: scan phy mdio-mux at address 10 [ 18.175762] mdio_bus stmmac-0: scan phy mdio-mux at address 11 [ 18.175795] mdio_bus stmmac-0: scan phy mdio-mux at address 12 [ 18.175827] mdio_bus stmmac-0: scan phy mdio-mux at address 13 [ 18.175858] mdio_bus stmmac-0: scan phy mdio-mux at address 14 [ 18.175889] mdio_bus stmmac-0: scan phy mdio-mux at address 15 [ 18.175919] mdio_bus stmmac-0: scan phy mdio-mux at address 16 [ 18.175951] mdio_bus stmmac-0: scan phy mdio-mux at address 17 [ 18.175982] mdio_bus stmmac-0: scan phy mdio-mux at address 18 [ 18.176014] mdio_bus stmmac-0: scan phy mdio-mux at address 19 [ 18.176045] mdio_bus stmmac-0: scan phy mdio-mux at address 20 [ 18.176076] mdio_bus stmmac-0: scan phy mdio-mux at address 21 [ 18.176107] mdio_bus stmmac-0: scan phy mdio-mux at address 22 [ 18.176139] mdio_bus stmmac-0: scan phy mdio-mux at address 23 [ 18.176170] mdio_bus stmmac-0: scan phy mdio-mux at address 24 [ 18.176202] mdio_bus stmmac-0: scan phy mdio-mux at address 25 [ 18.176233] mdio_bus stmmac-0: scan phy mdio-mux at address 26 [ 18.176271] mdio_bus stmmac-0: scan phy mdio-mux at address 27 [ 18.176320] mdio_bus stmmac-0: scan phy mdio-mux at address 28 [ 18.176371] mdio_bus stmmac-0: scan phy mdio-mux at address 29 [ 18.176420] mdio_bus stmmac-0: scan phy mdio-mux at address 30 [ 18.176452] mdio_bus stmmac-0: scan phy mdio-mux at address 31 Adding a fake <reg> to mdio-mux remove it, but I found that a bit ugly. Or perhaps patching of_mdiobus_register() to not scan node with compatible "mdio-mux". What do you think ? Regards -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
