On Tue, Apr 11, 2023 at 04:22:37PM +0200, Johannes Zink wrote: > Hi Krzystof, > > thank you for your explanations. As I'm still quite new to writing > bindings, I still have some questions: > > On Fri, 2023-04-07 at 11:03 +0200, Krzysztof Kozlowski wrote: > > On 05/04/2023 14:14, Johannes Zink wrote: > > > Hi Krysztof, > > > > > > thanks for your review, please find my questions below. > > > > > > On Wed, 2023-04-05 at 13:51 +0200, Krzysztof Kozlowski wrote: > > > > [snip] > > > > > A phandle to the regulator for USB VBUS. > > > > > > > > > > + fsl,phy-tx-vref-tune: > > > > > + description: > > > > > + HS DC Voltage level adjustment > > > > > > > > "Level" in what units? > > > > > > > > > > The datasheet just shows percent, ranging from -6 to +24%, in 2% > > > increments. What unit would you suggest? > > > > percent > > https://github.com/devicetree-org/dt-schema/blob/main/dtschema/schemas/property-units.yaml > > I am still a bit confused how to use this properly. How can I restrict > the values to multiples of 2 in order to avoid illegal values? > > At the moment the only thing I could come up with is something like > > fsl,phy-tx-vref-tune-percent: > description: | > Adjusts the high-speed DC level voltage > $ref: /schemas/types.yaml#/definitions/int32 Note that with standard unit suffixes, you don't need a type. > minimum: -6 > maximum: 24 > default: 0 > > Does something like this work? I am not quite sure if I am on the right > track here, especially as this requires a signed int, of which I have > not seen many examples so far. We'd have to change the type for -percent to signed. That's possible, but for vendor specific properties there's not much advantage to use standard units instead of just using the register values directly. Rob
