[PATCH 03/18] dt-bindings: mtd: nand-chip: Create a NAND chip description

[Rob Herring]

On Wed, Oct 20, 2021 at 04:27:54PM +0200, Miquel Raynal wrote:
> Move the NAND chip description out of the NAND controller file. Indeed,
> a subsequent part of the properties supported by a raw NAND chip are
> also supported by SPI-NAND chips. So let's create a generic NAND chip
> description which will be pulled by nand-controller.yaml and later by
> spi-nand.yaml as well.
> 
> Signed-off-by: Miquel Raynal <miquel.raynal at bootlin.com>
> ---
>  .../devicetree/bindings/mtd/nand-chip.yaml    | 71 +++++++++++++++++++
>  .../bindings/mtd/nand-controller.yaml         | 53 ++------------
>  2 files changed, 75 insertions(+), 49 deletions(-)
>  create mode 100644 Documentation/devicetree/bindings/mtd/nand-chip.yaml
> 
> diff --git a/Documentation/devicetree/bindings/mtd/nand-chip.yaml b/Documentation/devicetree/bindings/mtd/nand-chip.yaml
> new file mode 100644
> index 000000000000..1f230a3ee27d
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mtd/nand-chip.yaml
> @@ -0,0 +1,71 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/mtd/nand-chip.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: NAND Chip and NAND Controller Generic Binding
> +
> +maintainers:
> +  - Miquel Raynal <miquel.raynal at bootlin.com>
> +
> +description: |
> +  This file covers the generic description of a NAND chip. It implies that the
> +  bus interface should not be taken into account: both raw NAND devices and
> +  SPI-NAND devices are concerned by this description.
> +
> +properties:
> +  reg:
> +    description:
> +      Contains the chip-select IDs.
> +
> +  nand-ecc-engine:
> +    allOf:
> +      - $ref: /schemas/types.yaml#/definitions/phandle
> +    description: |
> +      A phandle on the hardware ECC engine if any. There are
> +      basically three possibilities:
> +      1/ The ECC engine is part of the NAND controller, in this
> +      case the phandle should reference the parent node.
> +      2/ The ECC engine is part of the NAND part (on-die), in this
> +      case the phandle should reference the node itself.
> +      3/ The ECC engine is external, in this case the phandle should
> +      reference the specific ECC engine node.
> +
> +  nand-use-soft-ecc-engine:
> +    type: boolean
> +    description: Use a software ECC engine.
> +
> +  nand-no-ecc-engine:
> +    type: boolean
> +    description: Do not use any ECC correction.
> +
> +  nand-ecc-algo:
> +    description:
> +      Desired ECC algorithm.
> +    $ref: /schemas/types.yaml#/definitions/string
> +    enum: [hamming, bch, rs]
> +
> +  nand-ecc-strength:
> +    description:
> +      Maximum number of bits that can be corrected per ECC step.
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    minimum: 1
> +
> +  nand-ecc-step-size:
> +    description:
> +      Number of data bytes covered by a single ECC step.
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    minimum: 1
> +
> +  secure-regions:
> +    $ref: /schemas/types.yaml#/definitions/uint64-matrix
> +    description:
> +      Regions in the NAND chip which are protected using a secure element
> +      like Trustzone. This property contains the start address and size of
> +      the secure regions present.
> +
> +required:
> +  - reg
> +
> +additionalProperties: false

This is the source of the errors reported as this wasn't set before. If 
we're allowing custom properties (not defined here) within nand chip 
nodes, then each schema with custom properties has to reference 
nand-chip.yaml, set 'unevaluatedProperties: false', and then define 
their custom properties. And then this needs to be true. 

Rob