dt-bindings: misc: Convert olpc,xo1.75-ec to json-schema

OLPC XO-1.75 Embedded Controller

Required properties:

- compatible: Should be "olpc,xo1.75-ec".

- cmd-gpios: gpio specifier of the CMD pin

The embedded controller requires the SPI controller driver to signal readiness

to receive a transfer (that is, when TX FIFO contains the response data) by

strobing the ACK pin with the ready signal. See the "ready-gpios" property of the

SSP binding as documented in:

<Documentation/devicetree/bindings/spi/marvell,mmp2-ssp.yaml>.

Example:

	&ssp3 {

		spi-slave;

		ready-gpios = <&gpio 125 GPIO_ACTIVE_HIGH>;

		slave {

			compatible = "olpc,xo1.75-ec";

			spi-cpha;

			cmd-gpios = <&gpio 155 GPIO_ACTIVE_HIGH>;

		};

	};

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

# Copyright (C) 2019,2020 Lubomir Rintel <lkundrak@v3.sk>

%YAML 1.2

---

$id: http://devicetree.org/schemas/misc/olpc,xo1.75-ec.yaml#

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

title: OLPC XO-1.75 Embedded Controller bindings

description: |

  This binding describes the Embedded Controller acting as a SPI bus master

  on a OLPC XO-1.75 laptop computer.

  The embedded controller requires the SPI controller driver to signal

  readiness to receive a transfer (that is, when TX FIFO contains the

  response data) by strobing the ACK pin with the ready signal. See the

  "ready-gpios" property of the SSP binding as documented in:

  <Documentation/devicetree/bindings/spi/marvell,mmp2-ssp.yaml>.

maintainers:

  - Lubomir Rintel <lkundrak@v3.sk>

properties:

  compatible:

    const: olpc,xo1.75-ec

  cmd-gpios:

    description: GPIO uspecifier of the CMD pin

    maxItems: 1

required:

  - compatible

  - cmd-gpios

unevaluatedProperties: false

examples:

  - |

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

    spi {

      spi-slave;

      ready-gpios = <&gpio 125 GPIO_ACTIVE_HIGH>;

      slave {

        compatible = "olpc,xo1.75-ec";

        spi-cpha;

        cmd-gpios = <&gpio 155 GPIO_ACTIVE_HIGH>;

      };

    };

...