Hello, On 10/2/20 10:20 AM, Krzysztof Kozlowski wrote: > On Fri, Oct 02, 2020 at 09:41:28AM +0200, Ahmad Fatoum wrote: >> Hello, >> >> On 10/1/20 12:37 PM, Krzysztof Kozlowski wrote: >>>> The existing binding doesn't cover these boards then and needs to be >>>> extended, no? How about following patch? >>> >>> What do you mean it doesn't cover? It was added exactly to handle them: >>> + - technexion,imx6q-pico-dwarf # TechNexion i.MX6Q Pico-Dwarf >>> + - technexion,imx6q-pico-hobbit # TechNexion i.MX6Q Pico-Hobbit >>> + - technexion,imx6q-pico-nymph # TechNexion i.MX6Q Pico-Nymph >>> + - technexion,imx6q-pico-pi # TechNexion i.MX6Q Pico-Pi >>> >> >> Still they are unused. So I'd think these boards should be handled like boards >> that predated bindings: a binding is written that doesn't break existing users. > > OK, let's assume the binding is not correct and DTSes are good. > >> >>>> [I guess we need to keep the two-compatible list they were originally >>>> in for compatibility even if it's unused among upstream device trees?] >>> >>> You want to change both the binding (thus breaking the ABI) and update >>> the DTS to reflect new ABI. Then why having a binding at all? >> >> If we leave the old two-compatible enumeration intact, there is no ABI broken. > > Just to clarify, because I don't get here the "no ABI broken" part: > ABI is the binding, not the DTS. We can change intree DTS as we like, > replace compatibles, add nodes, remove nodes. There is no stability > requirement for DTS contents. > If we leave two-compatible binding intact, it is a broken binding since > beginning. Removing non-working, fake ABI is not breaking it because it > could never work. Then I misunderstood you. I was thinking about possible out-of-tree users that have boards based on this and are adhering to the binding. Dropping the binding would break those (albeit it's a quite manageable form of brokenness here). >>> I would assume that either binding is correct or DTS. You propose that >>> both are wrong and both need changes... in such case this is clearly >>> broken. >> >> IMO the DTS is the correct one. If you want to honor the author's intention >> that each base board has a different compatible, it should be an extra >> compatible and not replace the existing one that may be already in use. > > OK, we can go with DTS approach. I fixed few of such cases as well, > assuming that DTS was intended and binding was incorrect. In such case > all boards will be documented under one compatible technexion,imx6q-pico > and DTS will not be changed. Sounds good. If further differentiation proves to be needed, it can be a new compatible added in a separate commit. Thanks Ahmad > > Best regards, > Krzysztof > -- Pengutronix e.K. | | Steuerwalder Str. 21 | http://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
