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If you >>>>> call >>>>> regulator_get() then the consumer really assumes a regulator must exist. But >>>>> if it >>>>> is something the kernel does not control we get a dummy one with very limited >>>>> functionality/stubs. If you call regulator_get_optional(), then the regulator >>>>> is >>>>> really optional and might not physically exist. Seems very similar to what >>>>> you have.  >>>> >>>> There could perhaps be use for a backend like this too. Is the idea such >>>> that one would still need to define a "iio-backend-simple" node or such >>>> to device tree which would then provide the backend link and compatible? >>>>   >>> >>> My idea would be to automatically define one if we fail to find it. Naturally if >>> we >>> ever add an optional() get the dummy could not be added. See how regulator_get() >>> handles it. That's basically what I have in mind. >>> >> It's an interesting idea, but I'd like some input from DT folk on this. >> The fake regulators thing is kind of legacy from lots of drivers gaining the >> power handling later and it being boring / too late to add all the fixed regs >> to DT.  This is a much less common case and I find it a little unlikely there >> is nothing useful to know about where the data is going - so how useful >> is an autocreated backend? >> > > Not really that useful. This was just something I thought of to have the full usecase > supported in Linux. But, if we can add an explicit fixed/dummy (whatever name fits > best) backend with a proper compatible that would be preferable, yes. For now I think we should be okay without a dummy backend. Once the capability feature is accepted this will be enough for current needs. The capabilites will bring in a lot of flexibility as to what needs to be implemented and not in the backend. In my case I can register a backend from a driver that is not exactly that, but provides related functionality. BR, Tomas > > - Nuno Sá >