dt-bindings: pwm: Convert Samsung PWM bindings to json-schema

* Samsung PWM timers

Samsung SoCs contain PWM timer blocks which can be used for system clock source

and clock event timers, as well as to drive SoC outputs with PWM signal. Each

PWM timer block provides 5 PWM channels (not all of them can drive physical

outputs - see SoC and board manual).

Be aware that the clocksource driver supports only uniprocessor systems.

Required properties:

- compatible : should be one of following:

    samsung,s3c2410-pwm - for 16-bit timers present on S3C24xx SoCs

    samsung,s3c6400-pwm - for 32-bit timers present on S3C64xx SoCs

    samsung,s5p6440-pwm - for 32-bit timers present on S5P64x0 SoCs

    samsung,s5pc100-pwm - for 32-bit timers present on S5PC100, S5PV210,

			  Exynos4210 rev0 SoCs

    samsung,exynos4210-pwm - for 32-bit timers present on Exynos4210,

                          Exynos4x12, Exynos5250 and Exynos5420 SoCs

- reg: base address and size of register area

- interrupts: list of timer interrupts (one interrupt per timer, starting at

  timer 0)

- clock-names: should contain all following required clock names:

    - "timers" - PWM base clock used to generate PWM signals,

  and any subset of following optional clock names:

    - "pwm-tclk0" - first external PWM clock source,

    - "pwm-tclk1" - second external PWM clock source.

  Note that not all IP variants allow using all external clock sources.

  Refer to SoC documentation to learn which clock source configurations

  are available.

- clocks: should contain clock specifiers of all clocks, which input names

  have been specified in clock-names property, in same order.

- #pwm-cells: should be 3. See pwm.txt in this directory for a description of

  the cells format. The only third cell flag supported by this binding is

  PWM_POLARITY_INVERTED.

Optional properties:

- samsung,pwm-outputs: list of PWM channels used as PWM outputs on particular

    platform - an array of up to 5 elements being indices of PWM channels

    (from 0 to 4), the order does not matter.

Example:

	pwm@7f006000 {

		compatible = "samsung,s3c6400-pwm";

		reg = <0x7f006000 0x1000>;

		interrupt-parent = <&vic0>;

		interrupts = <23>, <24>, <25>, <27>, <28>;

		clocks = <&clock 67>;

		clock-names = "timers";

		samsung,pwm-outputs = <0>, <1>;

		#pwm-cells = <3>;

	}

# SPDX-License-Identifier: GPL-2.0

%YAML 1.2

---

$id: http://devicetree.org/schemas/pwm/pwm-samsung.yaml#

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

title: Samsung SoC PWM timers

maintainers:

  - Thierry Reding <thierry.reding@gmail.com>

  - Krzysztof Kozlowski <krzk@kernel.org>

description: |+

  Samsung SoCs contain PWM timer blocks which can be used for system clock source

  and clock event timers, as well as to drive SoC outputs with PWM signal. Each

  PWM timer block provides 5 PWM channels (not all of them can drive physical

  outputs - see SoC and board manual).

  Be aware that the clocksource driver supports only uniprocessor systems.

allOf:

  - $ref: pwm.yaml#

properties:

  compatible:

    enum:

      - samsung,s3c2410-pwm             # 16-bit, S3C24xx

      - samsung,s3c6400-pwm             # 32-bit, S3C64xx

      - samsung,s5p6440-pwm             # 32-bit, S5P64x0

      - samsung,s5pc100-pwm             # 32-bit, S5PC100, S5PV210, Exynos4210 rev0 SoCs

      - samsung,exynos4210-pwm          # 32-bit, Exynos

  reg:

    maxItems: 1

  clocks:

    minItems: 1

    maxItems: 3

  clock-names:

    description: |

      Should contain all following required clock names:

      - "timers" - PWM base clock used to generate PWM signals,

      and any subset of following optional clock names:

      - "pwm-tclk0" - first external PWM clock source,

      - "pwm-tclk1" - second external PWM clock source.

      Note that not all IP variants allow using all external clock sources.

      Refer to SoC documentation to learn which clock source configurations

      are available.

    oneOf:

      - items:

        - const: timers

      - items:

        - const: timers

        - const: pwm-tclk0

      - items:

        - const: timers

        - const: pwm-tclk1

      - items:

        - const: timers

        - const: pwm-tclk0

        - const: pwm-tclk1

  interrupts:

    description:

      One interrupt per timer, starting at timer 0.

    minItems: 1

    maxItems: 5

  "#pwm-cells":

    description:

      The only third cell flag supported by this binding

      is PWM_POLARITY_INVERTED.

    const: 3

  samsung,pwm-outputs:

    description:

      A list of PWM channels used as PWM outputs on particular platform.

      It is an array of up to 5 elements being indices of PWM channels

      (from 0 to 4), the order does not matter.

    allOf:

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

      - uniqueItems: true

      - items:

          minimum: 0

          maximum: 4

required:

  - clocks

  - clock-names

  - compatible

  - interrupts

  - "#pwm-cells"

  - reg

additionalProperties: false

examples:

  - |

    pwm@7f006000 {

        compatible = "samsung,s3c6400-pwm";

        reg = <0x7f006000 0x1000>;

        interrupt-parent = <&vic0>;

        interrupts = <23>, <24>, <25>, <27>, <28>;

        clocks = <&clock 67>;

        clock-names = "timers";

        samsung,pwm-outputs = <0>, <1>;

        #pwm-cells = <3>;

    };