On Fri, 23 May 2025 19:26:48 +0200 Arkadiusz Kubalewski wrote: > +The device may support the Reference SYNC feature, which allows the combination > +of two inputs into a Reference SYNC pair. In this configuration, clock signals > +from both inputs are used to synchronize the dpll device. The higher frequency > +signal is utilized for the loop bandwidth of the DPLL, while the lower frequency > +signal is used to syntonize the output signal of the DPLL device. This feature > +enables the provision of a high-quality loop bandwidth signal from an external > +source. I'm uninitiated into the deeper arts of time sync, but to me this sounds like a reference clock. Are you trying not to call it clock because in time clock means a ticker, and this is an oscillator? > +A capable input provides a list of inputs that can be paired to create a > +Reference SYNC pair. To control this feature, the user must request a desired > +state for a target pin: use ``DPLL_PIN_STATE_CONNECTED`` to enable or > +``DPLL_PIN_STATE_DISCONNECTED`` to disable the feature. Only two pins can be > +bound to form a Reference SYNC pair at any given time. Mostly I got confused by the doc saying "Reference SYNC pair". I was expecting that you'll have to provide 2 ref sync signals. But IIUC the first signal is still the existing signal we lock into, so the pair is of a reference sync + an input pin? Not a pair of two reference syncs. IOW my reading of the doc made me expect 2 pins to always be passed in as ref sync, but the example from the cover letter shows only adding one.
