dt-bindings: at25: convert the binding document to yaml

EEPROMs (SPI) compatible with Atmel at25.

Required properties:

- compatible : Should be "<vendor>,<type>", and generic value "atmel,at25".

  Example "<vendor>,<type>" values:

    "anvo,anv32e61w"

    "microchip,25lc040"

    "st,m95m02"

    "st,m95256"

- reg : chip select number

- spi-max-frequency : max spi frequency to use

- pagesize : size of the eeprom page

- size : total eeprom size in bytes

- address-width : number of address bits (one of 8, 9, 16, or 24).

  For 9 bits, the MSB of the address is sent as bit 3 of the instruction

  byte, before the address byte.

Optional properties:

- spi-cpha : SPI shifted clock phase, as per spi-bus bindings.

- spi-cpol : SPI inverse clock polarity, as per spi-bus bindings.

- read-only : this parameter-less property disables writes to the eeprom

- wp-gpios : GPIO to which the write-protect pin of the chip is connected

Obsolete legacy properties can be used in place of "size", "pagesize",

"address-width", and "read-only":

- at25,byte-len : total eeprom size in bytes

- at25,addr-mode : addr-mode flags, as defined in include/linux/spi/eeprom.h

- at25,page-size : size of the eeprom page

Additional compatible properties are also allowed.

Example:

	eeprom@0 {

		compatible = "st,m95256", "atmel,at25";

		reg = <0>

		spi-max-frequency = <5000000>;

		spi-cpha;

		spi-cpol;

		wp-gpios = <&gpio1 3 0>;

		pagesize = <64>;

		size = <32768>;

		address-width = <16>;

	};

# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause

%YAML 1.2

---

$id: "http://devicetree.org/schemas/eeprom/at25.yaml#"

$schema: "http://devicetree.org/meta-schemas/core.yaml#"

title: SPI EEPROMs compatible with Atmel's AT25

maintainers:

  - Christian Eggers <ceggers@arri.de>

properties:

  $nodename:

    pattern: "^eeprom@[0-9a-f]{1,2}$"

  # There are multiple known vendors who manufacture EEPROM chips compatible

  # with Atmel's AT25. The compatible string requires two items where the

  # 'vendor' and 'model' parts of the first are the actual chip and the second

  # item is fixed to "atmel,at25". Some existing bindings only have the

  # "atmel,at25" part and should be fixed by somebody who knows vendor and

  # product.

  compatible:

    oneOf:

      - items:

          - enum:

              - anvo,anv32e61w

              - atmel,at25256B

              - fujitsu,mb85rs1mt

              - fujitsu,mb85rs64

              - microchip,at25160bn

              - microchip,25lc040

              - st,m95m02

              - st,m95256

          - const: atmel,at25

      # Please don't use this alternative for new bindings.

      - items:

          - const: atmel,at25

  reg:

    description:

      Chip select number.

  spi-max-frequency: true

  pagesize:

    $ref: /schemas/types.yaml#definitions/uint32

    enum: [1, 8, 16, 32, 64, 128, 256, 512, 1024, 2048, 4096, 8192, 16384, 32768, 65536, 131072]

    description:

      Size of the eeprom page.

  size:

    $ref: /schemas/types.yaml#definitions/uint32

    description:

      Total eeprom size in bytes.

  address-width:

    $ref: /schemas/types.yaml#/definitions/uint32

    enum: [ 8, 9, 16, 24 ]

    description:

      Number of address bits.

      For 9 bits, the MSB of the address is sent as bit 3 of the instruction

      byte, before the address byte.

  spi-cpha: true

  spi-cpol: true

  read-only:

    description:

      Disable writes to the eeprom.

    type: boolean

  wp-gpios:

    maxItems: 1

    description:

      GPIO to which the write-protect pin of the chip is connected.

  # Deprecated: at25,byte-len, at25,addr-mode, at25,page-size

  at25,byte-len:

    $ref: /schemas/types.yaml#/definitions/uint32

    description:

       Total eeprom size in bytes. Deprecated, use "size" property instead.

    deprecated: true

  at25,addr-mode:

    $ref: /schemas/types.yaml#/definitions/uint32

    description:

       Addr-mode flags, as defined in include/linux/spi/eeprom.h.

       Deprecated, use "address-width" property instead.

    deprecated: true

  at25,page-size:

    $ref: /schemas/types.yaml#/definitions/uint32

    description:

      Size of the eeprom page. Deprecated, use "pagesize" property instead.

    deprecated: true

required:

  - compatible

  - reg

  - spi-max-frequency

  - pagesize

  - size

  - address-width

additionalProperties: false

examples:

  - |

    #include <dt-bindings/gpio/gpio.h>

    spi0 {

        #address-cells = <1>;

        #size-cells = <0>;

        eeprom@0 {

            compatible = "st,m95256", "atmel,at25";

            reg = <0>;

            spi-max-frequency = <5000000>;

            spi-cpha;

            spi-cpol;

            wp-gpios = <&gpio1 3 0>;

            pagesize = <64>;

            size = <32768>;

            address-width = <16>;

        };

    };