watchdog: dt-bindings: atmel,at91sam9-wdt: convert to json-schema

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

# Copyright (C) 2022 Microchip Technology, Inc. and its subsidiaries

%YAML 1.2

---

$id: http://devicetree.org/schemas/watchdog/atmel,at91sam9-wdt.yaml#

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

title: Atmel Watchdog Timers

maintainers:

  - Eugen Hristev <eugen.hristev@microchip.com>

properties:

  compatible:

    const: atmel,at91sam9260-wdt

  reg:

    maxItems: 1

  clocks:

    maxItems: 1

  interrupts:

    maxItems: 1

  atmel,max-heartbeat-sec:

    description:

      Should contain the maximum heartbeat value in seconds. This value

      should be less or equal to 16. It is used to compute the WDV field.

    maximum: 16

  atmel,min-heartbeat-sec:

    description:

      Should contain the minimum heartbeat value in seconds. This value

      must be smaller than the max-heartbeat-sec value. It is used to

      compute the WDD field.

    maximum: 16

  atmel,watchdog-type:

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

    description: |

      Should be hardware or software.

    oneOf:

      - description:

          Hardware watchdog uses the at91 watchdog reset.

        const: hardware

      - description: |

          Software watchdog uses the watchdog interrupt

          to trigger a software reset.

        const: software

    default: hardware

  atmel,reset-type:

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

    description: |

      Should be proc or all. This is valid only when using hardware watchdog.

    oneOf:

      - description:

          Assert peripherals and processor reset signals.

        const: all

      - description:

          Assert the processor reset signal.

        const: proc

    default: all

  atmel,disable:

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

    description:

      Should be present if you want to stop the watchdog.

  atmel,idle-halt:

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

    description: |

      Should be present if you want to stop the watchdog when

      entering idle state.

      CAUTION: This property should be used with care, it actually makes the

      watchdog not counting when the CPU is in idle state, therefore the

      watchdog reset time depends on mean CPU usage and will not reset at all

      if the CPU stops working while it is in idle state, which is probably

      not what you want.

  atmel,dbg-halt:

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

    description: |

      Should be present if you want to stop the watchdog when

      entering debug state.

required:

  - compatible

  - reg

  - clocks

allOf:

  - $ref: watchdog.yaml#

  - if:

      properties:

        atmel,reset-type:

          enum:

            - all

            - proc

    then:

      properties:

        atmel,watchdog-type:

          const: hardware

dependencies:

  atmel,reset-type: ['atmel,watchdog-type']

unevaluatedProperties: false

examples:

  - |

    #include <dt-bindings/interrupt-controller/irq.h>

    watchdog@fffffd40 {

        compatible = "atmel,at91sam9260-wdt";

        reg = <0xfffffd40 0x10>;

        interrupts = <1 IRQ_TYPE_LEVEL_HIGH 7>;

        clocks = <&clk32k>;

        timeout-sec = <15>;

        atmel,watchdog-type = "hardware";

        atmel,reset-type = "all";

        atmel,dbg-halt;

        atmel,idle-halt;

        atmel,max-heartbeat-sec = <16>;

        atmel,min-heartbeat-sec = <0>;

    };

* Atmel Watchdog Timers

** at91sam9-wdt

Required properties:

- compatible: must be "atmel,at91sam9260-wdt".

- reg: physical base address of the controller and length of memory mapped

  region.

- clocks: phandle to input clock.

Optional properties:

- timeout-sec: contains the watchdog timeout in seconds.

- interrupts : Should contain WDT interrupt.

- atmel,max-heartbeat-sec : Should contain the maximum heartbeat value in

	seconds. This value should be less or equal to 16. It is used to

	compute the WDV field.

- atmel,min-heartbeat-sec : Should contain the minimum heartbeat value in

	seconds. This value must be smaller than the max-heartbeat-sec value.

	It is used to compute the WDD field.

- atmel,watchdog-type : Should be "hardware" or "software". Hardware watchdog

	use the at91 watchdog reset. Software watchdog use the watchdog

	interrupt to trigger a software reset.

- atmel,reset-type : Should be "proc" or "all".

	"all" : assert peripherals and processor reset signals

	"proc" : assert the processor reset signal

	This is valid only when using "hardware" watchdog.

- atmel,disable : Should be present if you want to disable the watchdog.

- atmel,idle-halt : Should be present if you want to stop the watchdog when

	entering idle state.

	CAUTION: This property should be used with care, it actually makes the

	watchdog not counting when the CPU is in idle state, therefore the

	watchdog reset time depends on mean CPU usage and will not reset at all

	if the CPU stop working while it is in idle state, which is probably

	not what you want.

- atmel,dbg-halt : Should be present if you want to stop the watchdog when

	entering debug state.

Example:

	watchdog@fffffd40 {

		compatible = "atmel,at91sam9260-wdt";

		reg = <0xfffffd40 0x10>;

		interrupts = <1 IRQ_TYPE_LEVEL_HIGH 7>;

		clocks = <&clk32k>;

		timeout-sec = <15>;

		atmel,watchdog-type = "hardware";

		atmel,reset-type = "all";

		atmel,dbg-halt;

		atmel,idle-halt;

		atmel,max-heartbeat-sec = <16>;

		atmel,min-heartbeat-sec = <0>;

	};