On Mon, Oct 05, 2020 at 11:26:23PM +0100, Cristian Marussi wrote:

+An SCMI Regulator is permanently bound to a well defined SCMI Voltage Domain,
+and should be always positioned as a root regulator.
+It does not support negative voltages nor any current operation.

Support for negative voltages is an implementation detail of Linux, IIRC
there's nothing in the generic regulator binding preventing it and even
if there were updates to the generic binding are what are relevant here
- they could start working with no updates to this binding.

+Optional properties:
+ - regulator-min-microvolt: when defined should be non-negative.
+ - regulator-max-microvolt: when defined should be non-negative.

These are covered by the generic regulator binding, no need to duplicate
the documentation here.