dt-bindings: mfd: Convert stm32 low power timers bindings to json-schema

STMicroelectronics STM32 Low-Power Timer quadrature encoder and counter

STM32 Low-Power Timer provides several counter modes. It can be used as:

- quadrature encoder to detect angular position and direction of rotary

  elements, from IN1 and IN2 input signals.

- simple counter from IN1 input signal.

Must be a sub-node of an STM32 Low-Power Timer device tree node.

See ../mfd/stm32-lptimer.txt for details about the parent node.

Required properties:

- compatible:		Must be "st,stm32-lptimer-counter".

- pinctrl-names: 	Set to "default". An additional "sleep" state can be

			defined to set pins in sleep state.

- pinctrl-n: 		List of phandles pointing to pin configuration nodes,

			to set IN1/IN2 pins in mode of operation for Low-Power

			Timer input on external pin.

Example:

	timer@40002400 {

		compatible = "st,stm32-lptimer";

		...

		counter {

			compatible = "st,stm32-lptimer-counter";

			pinctrl-names = "default", "sleep";

			pinctrl-0 = <&lptim1_in_pins>;

			pinctrl-1 = <&lptim1_sleep_in_pins>;

		};

	};

STMicroelectronics STM32 Low-Power Timer Trigger

STM32 Low-Power Timer provides trigger source (LPTIM output) that can be used

by STM32 internal ADC and/or DAC.

Must be a sub-node of an STM32 Low-Power Timer device tree node.

See ../mfd/stm32-lptimer.txt for details about the parent node.

Required properties:

- compatible:		Must be "st,stm32-lptimer-trigger".

- reg:			Identify trigger hardware block. Must be 0, 1 or 2

			respectively for lptimer1, lptimer2 or lptimer3

			trigger output.

Example:

	timer@40002400 {

		compatible = "st,stm32-lptimer";

		...

		trigger@0 {

			compatible = "st,stm32-lptimer-trigger";

			reg = <0>;

		};

	};

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

%YAML 1.2

---

$id: http://devicetree.org/schemas/mfd/st,stm32-lptimer.yaml#

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

title: STMicroelectronics STM32 Low-Power Timers bindings

description: |

  The STM32 Low-Power Timer (LPTIM) is a 16-bit timer that provides several

  functions

   - PWM output (with programmable prescaler, configurable polarity)

   - Trigger source for STM32 ADC/DAC (LPTIM_OUT)

   - Several counter modes:

     - quadrature encoder to detect angular position and direction of rotary

       elements, from IN1 and IN2 input signals.

     - simple counter from IN1 input signal.

maintainers:

  - Fabrice Gasnier <fabrice.gasnier@st.com>

properties:

  compatible:

    const: st,stm32-lptimer

  reg:

    maxItems: 1

  clocks:

    maxItems: 1

  clock-names:

    items:

      - const: mux

  "#address-cells":

    const: 1

  "#size-cells":

    const: 0

  pwm:

    type: object

    properties:

      compatible:

        const: st,stm32-pwm-lp

      "#pwm-cells":

        const: 3

    required:

      - "#pwm-cells"

      - compatible

patternProperties:

  "^trigger@[0-9]+$":

    type: object

    properties:

      compatible:

        const: st,stm32-lptimer-trigger

      reg:

        description: Identify trigger hardware block.

        items:

         minimum: 0

         maximum: 2

    required:

      - compatible

      - reg

  counter:

    type: object

    properties:

      compatible:

        const: st,stm32-lptimer-counter

    required:

      - compatible

required:

  - "#address-cells"

  - "#size-cells"

  - compatible

  - reg

  - clocks

  - clock-names

additionalProperties: false

examples:

  - |

    #include <dt-bindings/clock/stm32mp1-clks.h>

    timer@40002400 {

      compatible = "st,stm32-lptimer";

      reg = <0x40002400 0x400>;

      clocks = <&timer_clk>;

      clock-names = "mux";

      #address-cells = <1>;

      #size-cells = <0>;

      pwm {

        compatible = "st,stm32-pwm-lp";

        #pwm-cells = <3>;

      };

      trigger@0 {

        compatible = "st,stm32-lptimer-trigger";

        reg = <0>;

      };

      counter {

        compatible = "st,stm32-lptimer-counter";

      };

    };

...

STMicroelectronics STM32 Low-Power Timer

The STM32 Low-Power Timer (LPTIM) is a 16-bit timer that provides several

functions:

- PWM output (with programmable prescaler, configurable polarity)

- Quadrature encoder, counter

- Trigger source for STM32 ADC/DAC (LPTIM_OUT)

Required properties:

- compatible:		Must be "st,stm32-lptimer".

- reg:			Offset and length of the device's register set.

- clocks:		Phandle to the clock used by the LP Timer module.

- clock-names:		Must be "mux".

- #address-cells:	Should be '<1>'.

- #size-cells:		Should be '<0>'.

Optional subnodes:

- pwm:			See ../pwm/pwm-stm32-lp.txt

- counter:		See ../counter/stm32-lptimer-cnt.txt

- trigger:		See ../iio/timer/stm32-lptimer-trigger.txt

Example:

	timer@40002400 {

		compatible = "st,stm32-lptimer";

		reg = <0x40002400 0x400>;

		clocks = <&timer_clk>;

		clock-names = "mux";

		#address-cells = <1>;

		#size-cells = <0>;

		pwm {

			compatible = "st,stm32-pwm-lp";

			pinctrl-names = "default";

			pinctrl-0 = <&lppwm1_pins>;

		};

		trigger@0 {

			compatible = "st,stm32-lptimer-trigger";

			reg = <0>;

		};

		counter {

			compatible = "st,stm32-lptimer-counter";

			pinctrl-names = "default";

			pinctrl-0 = <&lptim1_in_pins>;

		};

	};

STMicroelectronics STM32 Low-Power Timer PWM

STM32 Low-Power Timer provides single channel PWM.

Must be a sub-node of an STM32 Low-Power Timer device tree node.

See ../mfd/stm32-lptimer.txt for details about the parent node.

Required parameters:

- compatible:		Must be "st,stm32-pwm-lp".

- #pwm-cells:		Should be set to 3. This PWM chip uses the default 3 cells

			bindings defined in pwm.yaml.

Optional properties:

- pinctrl-names: 	Set to "default". An additional "sleep" state can be

			defined to set pins in sleep state when in low power.

- pinctrl-n: 		Phandle(s) pointing to pin configuration node for PWM,

			respectively for "default" and "sleep" states.

Example:

	timer@40002400 {

		compatible = "st,stm32-lptimer";

		...

		pwm {

			compatible = "st,stm32-pwm-lp";

			#pwm-cells = <3>;

			pinctrl-names = "default", "sleep";

			pinctrl-0 = <&lppwm1_pins>;

			pinctrl-1 = <&lppwm1_sleep_pins>;

		};

	};