On Tue, Jul 16, 2013 at 6:30 PM, Stephen Warren <swar...@wwwdotorg.org> wrote: > On 07/15/2013 05:02 PM, Stephen Warren wrote: >> On 07/15/2013 01:34 PM, Rob Herring wrote: >>> On 07/15/2013 01:40 PM, Stephen Warren wrote: >>>> From: Stephen Warren <swar...@nvidia.com> >>>> >>>> This property is no longer required by the GPIO binding. Remove it. >>> >>> Won't this break compatibility with older kernel? It is one thing to >>> deprecate, but removal is another. If the relevant maintainers don't >>> care, then I guess it is fine. >> >> Yes. >> >> I had originally hoped this could sneak in late for 3.11, but I suppose >> it's too late now. vf610.dtsi is a new file in 3.11 so has no legacy to >> protect. >> >> Admittedly, the #gpio-cells property was added into the SPEAr files in 3.10. > > One more thought here: > > I know DT bindings are supposed to evolve so that a new kernel will > support arbitrary old DTs. I'll call that backwards-compatibility for > the DT parsing code.
That is the more common case. > However, this situation is the reverse; this patch would prevent a new > DT running on an older kernel. I'll call that forwards-compatibility. > I'm not sure if the intent is to support this or not? It's certainly the > first I explicitly thought about compatibility in this direction... So you would be okay if your computer stopped booting a kernel after a BIOS update? It's the same deal. It's both forwards and backwards compatibility that is needed. Rob _______________________________________________ devicetree-discuss mailing list devicetree-discuss@lists.ozlabs.org https://lists.ozlabs.org/listinfo/devicetree-discuss