Hi Keguang, > +patternProperties: > + "^nand@[0-3]$": > + type: object > + $ref: raw-nand-chip.yaml > + > + required: > + - nand-use-soft-ecc-engine > + - nand-ecc-algo Actually I told you a mistake. The no-ecc-engine case should remain valid, so we cannot require these properties in the bindings. My fault, sorry about that. Thanks, Miquèl