On Tue, Jan 26, 2016 at 1:36 PM, Andrew Lunn <andrew@xxxxxxx> wrote: > On Tue, Jan 26, 2016 at 12:46:31PM -0800, Florian Fainelli wrote: >> On 26/01/16 10:14, Olof Johansson wrote: >> > +devicetree@xxxxxxxxxxxxxxx instead. >> > >> > On Tue, Jan 26, 2016 at 10:08 AM, Olof Johansson <olof@xxxxxxxxx> wrote: >> >> On Tue, Jan 26, 2016 at 9:53 AM, Andrew Lunn <andrew@xxxxxxx> wrote: >> >>>> I hate to bikeshed, but I'm not sure if "generic-mdio" is too... >> >>>> generic? Will someone writing a DT be thinking "well, this is a >> >>>> generic mdio PHY, I should set it"? "mdio-device"? >> >>>> "generic-nonphy-mdio"? Neither of those seem much better. >> >>> >> >>> How about 'not-a-phy'? >> >> >> >> "mdio,not-a-phy" or "mdio,non-phy" will scope it a bit, especially if >> >> you expect other generic mdio properties that can do with a namespace. >> >> Really not a fan of having to add an additional boolean property to >> differentiate an Ethernet PHY from something else, the proper solution >> would really be to enforce the use of the c22 or c45 compatible string >> as the least compatible string to be used, but I am assuming this is not >> necessarily an option here with DTBs out there. > > Nope, not an option. Only a small number of DTB actually use c22 or > c45. The majority of devices have no compatible at all. Why should > they, the binding documentation says it is optional! So one thing that can be done is to just have a whitelist in the driver that we add the known phy compatibles to, with a nice comment above that this should only be for legacy device trees. I.e. in addition to the c22 or c45 strings. You can even fix up existing trees, and do a pr_warn() for these cases to ask people to update their DT. There's no strict requirement to do so though, so the kernel still *has* to work with the old ones. >> What plays in favor of this boolean property is that the very concept of >> MDIO devices has been recently introduced, so presumably, there are not >> that many DTBs out there which would be affected... > > In kernel, 0. I have one out of kernel, which i hope to contribute > once we decide on the new binding for DSA. > >> The only other idea I had was to force the MDIO device creation to be >> dependent on finding a matching compatible string provided by a driver >> (yikes). > > Complex. There are ordering issues, since the driver can be loaded a > long time after of_mdiobus_register() is called, yet it needs to be > of_mdiobus_register() which decides if a device is a PHY or not. > > I think the bool is the only practical solution. -Olof -- 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
