Hi Rob > > > > + dai: > > > > + type: object > > > > + properties: > > > > + sound-dai: > > > > + $ref: /schemas/types.yaml#/definitions/phandle-array > > > > > > This should have a common definition elsewhere which I'd prefer be in > > > the dtschema repo. You can just assume there is and do 'maxItems: 1' > > > here assuming it's only 1. > > > > I think dai and/or sound-dai are not common definition. > > These are very simple-card specific property. > > Qcom platforms also use 'sound-dai' and they aren't simple-card. OK, I see. But, as you know I'm not 100% understanding about yaml Documentation. Can you teach me what is "dtschema repo" ? (I guess it means "sound-dai" will be common schema ?) What should I do ? Thank you for your help !! Best regards --- Kuninori Morimoto