>> + >> +Optional properties: >> + - vref-supply: phandle to the external reference voltage supply. >> + This should only be set if there is an external reference voltage >> + connected to the vref or vref[A-D] pins. > > I don't understand. Surely the latter case means you're describing the > same supply twice (as it should already be in vref*-supply)? > > What vref pins does the HW actually have?
Some off the devices supported by the binding have a shared reference for all DAC outputs, while others have a separate reference for each output. In addition to that some of them have an internal reference that can used, in which case the external reference is optional, otherwise the external reference is required. The bindings documentation should clarify on which applies to which device. -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
