dt-bindings: iio: adc: stm32-adc: convert bindings to json-schema

Commit Message

Fabrice Gasnier Nov. 27, 2019, 4:48 p.m. UTC

Convert the STM32 ADC binding to DT schema format using json-schema

Signed-off-by: Fabrice Gasnier <[e-mail]>
---
Note: this applies on top of IIO tree currently (iio-for-5.5c).
---
 .../devicetree/bindings/iio/adc/st,stm32-adc.txt   | 149 -------
 .../devicetree/bindings/iio/adc/st,stm32-adc.yaml  | 448 +++++++++++++++++++++
 2 files changed, 448 insertions(+), 149 deletions(-)
 delete mode 100644 Documentation/devicetree/bindings/iio/adc/st,stm32-adc.txt
 create mode 100644 Documentation/devicetree/bindings/iio/adc/st,stm32-adc.yaml

Comments

Jonathan Cameron Dec. 1, 2019, 9:08 p.m. UTC | #1

On Wed, 27 Nov 2019 17:48:45 +0100
Fabrice Gasnier <[e-mail]> wrote:

> Convert the STM32 ADC binding to DT schema format using json-schema
> 
> Signed-off-by: Fabrice Gasnier <[e-mail]>
This one is complex enough that I'm going to leave it to the experts :)
Definitely one for the DT maintainers.

Jonathan

> ---
> Note: this applies on top of IIO tree currently (iio-for-5.5c).
> diff --git a/Documentation/devicetree/bindings/iio/adc/st,stm32-adc.yaml b/Documentation/devicetree/bindings/iio/adc/st,stm32-adc.yaml
> new file mode 100644
> index 00000000..2ebc2e6
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/iio/adc/st,stm32-adc.yaml
> @@ -0,0 +1,448 @@
> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: "http://devicetree.org/schemas/bindings/iio/adc/st,stm32-adc.yaml#"
> +$schema: "http://devicetree.org/meta-schemas/core.yaml#"
> +
> +title: STMicroelectronics STM32 ADC bindings
> +
> +description: |
> +  STM32 ADC is a successive approximation analog-to-digital converter.
> +  It has several multiplexed input channels. Conversions can be performed
> +  in single, continuous, scan or discontinuous mode. Result of the ADC is
> +  stored in a left-aligned or right-aligned 32-bit data register.
> +  Conversions can be launched in software or using hardware triggers.
> +
> +  The analog watchdog feature allows the application to detect if the input
> +  voltage goes beyond the user-defined, higher or lower thresholds.
> +
> +  Each STM32 ADC block can have up to 3 ADC instances.
> +
> +maintainers:
> +  - Fabrice Gasnier <[e-mail]>
> +
> +properties:
> +  compatible:
> +    enum:
> +      - st,stm32f4-adc-core
> +      - st,stm32h7-adc-core
> +      - st,stm32mp1-adc-core
> +
> +  reg:
> +    description: Offset and length of the ADC block register set
> +    maxItems: 1
> +
> +  interrupts:
> +    description: |
> +      One or more interrupts for ADC block, depending on part used:
> +        - stm32f4 and stm32h7 share a common ADC interrupt line.
> +        - stm32mp1 has two separate interrupt lines, one for each ADC within
> +          ADC block.
> +
> +  clocks:
> +    description: |
> +      Core can use up to two clocks, depending on part used:
> +        - "adc" clock: for the analog circuitry, common to all ADCs.
> +          It's required on stm32f4.
> +          It's optional on stm32h7 and stm32mp1.
> +        - "bus" clock: for registers access, common to all ADCs.
> +          It's not present on stm32f4.
> +          It's required on stm32h7 and stm32mp1.
> +
> +  clock-names: true
> +
> +  st,max-clk-rate-hz:
> +    description: |
> +      Allow to specify desired max clock rate used by analog circuitry.
> +    allOf:
> +      - $ref: /schemas/types.yaml#/definitions/uint32
> +
> +  vdda-supply:
> +    description: Phandle to the vdda input analog voltage.
> +
> +  vref-supply:
> +    description: Phandle to the vref input analog reference voltage.
> +
> +  booster-supply:
> +    description: |
> +      Phandle to the embedded booster regulator that can be used to supply ADC
> +      analog input switches on stm32h7 and stm32mp1.
> +
> +  vdd-supply:
> +    description: |
> +      Phandle to the vdd input voltage. It can be used to supply ADC analog
> +      input switches on stm32mp1.
> +
> +  st,syscfg:
> +    description: |
> +      Phandle to system configuration controller. It can be used to control the
> +      analog circuitry on stm32mp1.
> +    allOf:
> +      - $ref: "/schemas/types.yaml#/definitions/phandle-array"
> +
> +  interrupt-controller: true
> +
> +  '#interrupt-cells':
> +    const: 1
> +
> +  '#address-cells':
> +    const: 1
> +
> +  '#size-cells':
> +    const: 0
> +
> +allOf:
> +  - if:
> +      properties:
> +        compatible:
> +          contains:
> +            const: st,stm32f4-adc-core
> +
> +    then:
> +      properties:
> +        clocks:
> +          maxItems: 1
> +
> +        clock-names:
> +          items:
> +            const: adc
> +          maxItems: 1
> +
> +        interrupts:
> +          items:
> +            - description: interrupt line common for all ADCs
> +
> +        booster-supply: false
> +
> +        vdd-supply: false
> +
> +        st,syscfg: false
> +
> +  - if:
> +      properties:
> +        compatible:
> +          contains:
> +            const: st,stm32h7-adc-core
> +
> +    then:
> +      properties:
> +        clocks:
> +          minItems: 1
> +          maxItems: 2
> +
> +        clock-names:
> +          items:
> +            - const: bus
> +            - const: adc
> +          minItems: 1
> +          maxItems: 2
> +
> +        interrupts:
> +          items:
> +            - description: interrupt line common for all ADCs
> +
> +        vdd-supply: false
> +
> +        st,syscfg: false
> +
> +  - if:
> +      properties:
> +        compatible:
> +          contains:
> +            const: st,stm32mp1-adc-core
> +
> +    then:
> +      properties:
> +        clocks:
> +          minItems: 1
> +          maxItems: 2
> +
> +        clock-names:
> +          items:
> +            - const: bus
> +            - const: adc
> +          minItems: 1
> +          maxItems: 2
> +
> +        interrupts:
> +          items:
> +            - description: interrupt line for ADC1
> +            - description: interrupt line for ADC2
> +
> +additionalProperties: false
> +
> +required:
> +  - compatible
> +  - reg
> +  - interrupts
> +  - clocks
> +  - clock-names
> +  - vdda-supply
> +  - vref-supply
> +  - interrupt-controller
> +  - '#interrupt-cells'
> +  - '#address-cells'
> +  - '#size-cells'
> +
> +patternProperties:
> +  "^adc@[0-9]+$":
> +    type: object
> +    description: |
> +      An ADC block node should contain at least one subnode, representing an
> +      ADC instance available on the machine.
> +
> +    properties:
> +      compatible:
> +        enum:
> +          - st,stm32f4-adc
> +          - st,stm32h7-adc
> +          - st,stm32mp1-adc
> +
> +      reg:
> +        description: |
> +          Offset of ADC instance in ADC block. Valid values are:
> +            - 0x0:   ADC1
> +            - 0x100: ADC2
> +            - 0x200: ADC3 (stm32f4 only)
> +        maxItems: 1
> +
> +      '#io-channel-cells':
> +        const: 1
> +
> +      interrupts:
> +        description: |
> +          IRQ Line for the ADC instance. Valid values are:
> +            - 0 for adc@0
> +            - 1 for adc@100
> +            - 2 for adc@200 (stm32f4 only)
> +        maxItems: 1
> +
> +      clocks:
> +        description: |
> +          Input clock private to this ADC instance. It's required only on
> +          stm32f4, that has per instance clock input for registers access.
> +        maxItems: 1
> +
> +      dmas:
> +        description: RX DMA Channel
> +        maxItems: 1
> +
> +      dma-names:
> +        const: rx
> +
> +      assigned-resolution-bits:
> +        description: |
> +          Resolution (bits) to use for conversions:
> +            - can be 6, 8, 10 or 12 on stm32f4
> +            - can be 8, 10, 12, 14 or 16 on stm32h7 and stm32mp1
> +        allOf:
> +          - $ref: /schemas/types.yaml#/definitions/uint32
> +
> +      st,adc-channels:
> +        description: |
> +          List of single-ended channels muxed for this ADC. It can have up to:
> +            - 16 channels, numbered from 0 to 15 (for in0..in15) on stm32f4
> +            - 20 channels, numbered from 0 to 19 (for in0..in19) on stm32h7 and
> +              stm32mp1.
> +        allOf:
> +          - $ref: /schemas/types.yaml#/definitions/uint32-array
> +
> +      st,adc-diff-channels:
> +        description: |
> +          List of differential channels muxed for this ADC. Some channels can
> +          be configured as differential instead of single-ended on stm32h7 and
> +          on stm32mp1. Positive and negative inputs pairs are listed:
> +          <vinp vinn>, <vinp vinn>,... vinp and vinn are numbered from 0 to 19.
> +
> +          Note: At least one of "st,adc-channels" or "st,adc-diff-channels" is
> +          required. Both properties can be used together. Some channels can be
> +          used as single-ended and some other ones as differential (mixed). But
> +          channels can't be configured both as single-ended and differential.
> +        allOf:
> +          - $ref: /schemas/types.yaml#/definitions/uint32-matrix
> +          - items:
> +              items:
> +                - description: |
> +                    "vinp" indicates positive input number
> +                  minimum: 0
> +                  maximum: 19
> +                - description: |
> +                    "vinn" indicates negative input number
> +                  minimum: 0
> +                  maximum: 19
> +
> +      st,min-sample-time-nsecs:
> +        description: |
> +          Minimum sampling time in nanoseconds. Depending on hardware (board)
> +          e.g. high/low analog input source impedance, fine tune of ADC
> +          sampling time may be recommended. This can be either one value or an
> +          array that matches "st,adc-channels" and/or "st,adc-diff-channels"
> +          list, to set sample time resp. for all channels, or independently for
> +          each channel.
> +        allOf:
> +          - $ref: /schemas/types.yaml#/definitions/uint32-array
> +
> +    allOf:
> +      - if:
> +          properties:
> +            compatible:
> +              contains:
> +                const: st,stm32f4-adc
> +
> +        then:
> +          properties:
> +            reg:
> +              enum:
> +                - 0x0
> +                - 0x100
> +                - 0x200
> +
> +            interrupts:
> +              minimum: 0
> +              maximum: 2
> +
> +            assigned-resolution-bits:
> +              allOf:
> +                - enum: [6, 8, 10, 12]
> +                - default: 12
> +
> +            st,adc-channels:
> +              allOf:
> +                - maxItems: 16
> +                  items:
> +                    minimum: 0
> +                    maximum: 15
> +
> +            st,adc-diff-channels: false
> +
> +            st,min-sample-time-nsecs:
> +              allOf:
> +                - maxItems: 16
> +                  items:
> +                    minimum: 80
> +
> +          required:
> +            - clocks
> +
> +      - if:
> +          properties:
> +            compatible:
> +              contains:
> +                enum:
> +                  - st,stm32h7-adc
> +                  - st,stm32mp1-adc
> +
> +        then:
> +          properties:
> +            reg:
> +              enum:
> +                - 0x0
> +                - 0x100
> +
> +            interrupts:
> +              minimum: 0
> +              maximum: 1
> +
> +            assigned-resolution-bits:
> +              allOf:
> +                - enum: [8, 10, 12, 14, 16]
> +                - default: 16
> +
> +            st,adc-channels:
> +              allOf:
> +                - maxItems: 20
> +                  items:
> +                    minimum: 0
> +                    maximum: 19
> +
> +            st,min-sample-time-nsecs:
> +              allOf:
> +                - maxItems: 20
> +                  items:
> +                    minimum: 40
> +
> +    additionalProperties: false
> +
> +    anyOf:
> +      - required:
> +          - st,adc-channels
> +      - required:
> +          - st,adc-diff-channels
> +
> +    required:
> +      - compatible
> +      - reg
> +      - interrupts
> +      - '#io-channel-cells'
> +
> +examples:
> +  - |
> +    // Example 1: with stm32f429
> +      adc123: adc@40012000 {
> +        compatible = "st,stm32f4-adc-core";
> +        reg = <0x40012000 0x400>;
> +        interrupts = <18>;
> +        clocks = <&rcc 0 168>;
> +        clock-names = "adc";
> +        st,max-clk-rate-hz = <36000000>;
> +        vdda-supply = <&vdda>;
> +        vref-supply = <&vref>;
> +        interrupt-controller;
> +        #interrupt-cells = <1>;
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +        adc@0 {
> +          compatible = "st,stm32f4-adc";
> +          #io-channel-cells = <1>;
> +          reg = <0x0>;
> +          clocks = <&rcc 0 168>;
> +          interrupt-parent = <&adc123>;
> +          interrupts = <0>;
> +          st,adc-channels = <8>;
> +          dmas = <&dma2 0 0 0x400 0x0>;
> +          dma-names = "rx";
> +          assigned-resolution-bits = <8>;
> +        };
> +        // ...
> +        // other adc child nodes follow...
> +      };
> +
> +  - |
> +    // Example 2: with stm32mp157c to setup ADC1 with:
> +    // - channel 1 as single-ended
> +    // - channels 2 & 3 as differential (with resp. 6 & 7 negative inputs)
> +      #include <dt-bindings/interrupt-controller/arm-gic.h>
> +      #include <dt-bindings/clock/stm32mp1-clks.h>
> +      adc12: adc@48003000 {
> +        compatible = "st,stm32mp1-adc-core";
> +        reg = <0x48003000 0x400>;
> +        interrupts = <GIC_SPI 18 IRQ_TYPE_LEVEL_HIGH>,
> +                     <GIC_SPI 90 IRQ_TYPE_LEVEL_HIGH>;
> +        clocks = <&rcc ADC12>, <&rcc ADC12_K>;
> +        clock-names = "bus", "adc";
> +        booster-supply = <&booster>;
> +        vdd-supply = <&vdd>;
> +        vdda-supply = <&vdda>;
> +        vref-supply = <&vref>;
> +        st,syscfg = <&syscfg>;
> +        interrupt-controller;
> +        #interrupt-cells = <1>;
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +        adc@0 {
> +          compatible = "st,stm32mp1-adc";
> +          #io-channel-cells = <1>;
> +          reg = <0x0>;
> +          interrupt-parent = <&adc12>;
> +          interrupts = <0>;
> +          st,adc-channels = <1>;
> +          st,adc-diff-channels = <2 6>, <3 7>;
> +          st,min-sample-time-nsecs = <5000>;
> +          dmas = <&dmamux1 9 0x400 0x05>;
> +          dma-names = "rx";
> +        };
> +        // ...
> +        // other adc child node follow...
> +      };
> +
> +...

Rob Herring (Arm) Dec. 5, 2019, 10:24 p.m. UTC | #2

On Wed, Nov 27, 2019 at 05:48:45PM +0100, Fabrice Gasnier wrote:
> Convert the STM32 ADC binding to DT schema format using json-schema
> 
> Signed-off-by: Fabrice Gasnier <[e-mail]>
> ---
> Note: this applies on top of IIO tree currently (iio-for-5.5c).
> ---
>  .../devicetree/bindings/iio/adc/st,stm32-adc.txt   | 149 -------
>  .../devicetree/bindings/iio/adc/st,stm32-adc.yaml  | 448 +++++++++++++++++++++
>  2 files changed, 448 insertions(+), 149 deletions(-)
>  delete mode 100644 Documentation/devicetree/bindings/iio/adc/st,stm32-adc.txt
>  create mode 100644 Documentation/devicetree/bindings/iio/adc/st,stm32-adc.yaml


> diff --git a/Documentation/devicetree/bindings/iio/adc/st,stm32-adc.yaml b/Documentation/devicetree/bindings/iio/adc/st,stm32-adc.yaml
> new file mode 100644
> index 00000000..2ebc2e6
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/iio/adc/st,stm32-adc.yaml
> @@ -0,0 +1,448 @@
> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: "http://devicetree.org/schemas/bindings/iio/adc/st,stm32-adc.yaml#"
> +$schema: "http://devicetree.org/meta-schemas/core.yaml#"
> +
> +title: STMicroelectronics STM32 ADC bindings
> +
> +description: |
> +  STM32 ADC is a successive approximation analog-to-digital converter.
> +  It has several multiplexed input channels. Conversions can be performed
> +  in single, continuous, scan or discontinuous mode. Result of the ADC is
> +  stored in a left-aligned or right-aligned 32-bit data register.
> +  Conversions can be launched in software or using hardware triggers.
> +
> +  The analog watchdog feature allows the application to detect if the input
> +  voltage goes beyond the user-defined, higher or lower thresholds.
> +
> +  Each STM32 ADC block can have up to 3 ADC instances.
> +
> +maintainers:
> +  - Fabrice Gasnier <[e-mail]>
> +
> +properties:
> +  compatible:
> +    enum:
> +      - st,stm32f4-adc-core
> +      - st,stm32h7-adc-core
> +      - st,stm32mp1-adc-core
> +
> +  reg:
> +    description: Offset and length of the ADC block register set

Don't need generic description of a standard property.

> +    maxItems: 1
> +
> +  interrupts:
> +    description: |
> +      One or more interrupts for ADC block, depending on part used:
> +        - stm32f4 and stm32h7 share a common ADC interrupt line.
> +        - stm32mp1 has two separate interrupt lines, one for each ADC within
> +          ADC block.

You can put minItems: 1, maxItems: 2 here.

> +
> +  clocks:
> +    description: |
> +      Core can use up to two clocks, depending on part used:
> +        - "adc" clock: for the analog circuitry, common to all ADCs.
> +          It's required on stm32f4.
> +          It's optional on stm32h7 and stm32mp1.
> +        - "bus" clock: for registers access, common to all ADCs.
> +          It's not present on stm32f4.
> +          It's required on stm32h7 and stm32mp1.
> +
> +  clock-names: true
> +
> +  st,max-clk-rate-hz:
> +    description: |
> +      Allow to specify desired max clock rate used by analog circuitry.
> +    allOf:
> +      - $ref: /schemas/types.yaml#/definitions/uint32

*-hz already has a type, so you can drop this.

No range you can specify?

> +
> +  vdda-supply:
> +    description: Phandle to the vdda input analog voltage.
> +
> +  vref-supply:
> +    description: Phandle to the vref input analog reference voltage.
> +
> +  booster-supply:
> +    description: |

There's not any formatting here, so '|' can be dropped.

> +      Phandle to the embedded booster regulator that can be used to supply ADC
> +      analog input switches on stm32h7 and stm32mp1.
> +
> +  vdd-supply:
> +    description: |
> +      Phandle to the vdd input voltage. It can be used to supply ADC analog
> +      input switches on stm32mp1.
> +
> +  st,syscfg:
> +    description: |
> +      Phandle to system configuration controller. It can be used to control the
> +      analog circuitry on stm32mp1.
> +    allOf:
> +      - $ref: "/schemas/types.yaml#/definitions/phandle-array"
> +
> +  interrupt-controller: true
> +
> +  '#interrupt-cells':
> +    const: 1
> +
> +  '#address-cells':
> +    const: 1
> +
> +  '#size-cells':
> +    const: 0
> +
> +allOf:
> +  - if:
> +      properties:
> +        compatible:
> +          contains:
> +            const: st,stm32f4-adc-core
> +
> +    then:
> +      properties:
> +        clocks:
> +          maxItems: 1
> +
> +        clock-names:
> +          items:
> +            const: adc
> +          maxItems: 1

You can simplify to:

clock-names:
  const: adc

Note that if you did have 'items' it should be a list (i.e. have '-').

> +
> +        interrupts:
> +          items:
> +            - description: interrupt line common for all ADCs
> +
> +        booster-supply: false
> +
> +        vdd-supply: false
> +
> +        st,syscfg: false
> +
> +  - if:
> +      properties:
> +        compatible:
> +          contains:
> +            const: st,stm32h7-adc-core
> +
> +    then:
> +      properties:
> +        clocks:
> +          minItems: 1
> +          maxItems: 2
> +
> +        clock-names:
> +          items:
> +            - const: bus
> +            - const: adc
> +          minItems: 1
> +          maxItems: 2
> +
> +        interrupts:
> +          items:
> +            - description: interrupt line common for all ADCs
> +
> +        vdd-supply: false
> +
> +        st,syscfg: false
> +
> +  - if:
> +      properties:
> +        compatible:
> +          contains:
> +            const: st,stm32mp1-adc-core
> +
> +    then:
> +      properties:
> +        clocks:
> +          minItems: 1
> +          maxItems: 2
> +
> +        clock-names:
> +          items:
> +            - const: bus
> +            - const: adc
> +          minItems: 1
> +          maxItems: 2
> +
> +        interrupts:
> +          items:
> +            - description: interrupt line for ADC1
> +            - description: interrupt line for ADC2
> +
> +additionalProperties: false
> +
> +required:
> +  - compatible
> +  - reg
> +  - interrupts
> +  - clocks
> +  - clock-names
> +  - vdda-supply
> +  - vref-supply
> +  - interrupt-controller
> +  - '#interrupt-cells'
> +  - '#address-cells'
> +  - '#size-cells'
> +
> +patternProperties:
> +  "^adc@[0-9]+$":
> +    type: object
> +    description: |
> +      An ADC block node should contain at least one subnode, representing an
> +      ADC instance available on the machine.
> +
> +    properties:
> +      compatible:
> +        enum:
> +          - st,stm32f4-adc
> +          - st,stm32h7-adc
> +          - st,stm32mp1-adc
> +
> +      reg:
> +        description: |
> +          Offset of ADC instance in ADC block. Valid values are:
> +            - 0x0:   ADC1
> +            - 0x100: ADC2
> +            - 0x200: ADC3 (stm32f4 only)
> +        maxItems: 1
> +
> +      '#io-channel-cells':
> +        const: 1
> +
> +      interrupts:
> +        description: |
> +          IRQ Line for the ADC instance. Valid values are:
> +            - 0 for adc@0
> +            - 1 for adc@100
> +            - 2 for adc@200 (stm32f4 only)
> +        maxItems: 1
> +
> +      clocks:
> +        description: |
> +          Input clock private to this ADC instance. It's required only on
> +          stm32f4, that has per instance clock input for registers access.
> +        maxItems: 1
> +
> +      dmas:
> +        description: RX DMA Channel
> +        maxItems: 1
> +
> +      dma-names:
> +        const: rx
> +
> +      assigned-resolution-bits:
> +        description: |
> +          Resolution (bits) to use for conversions:
> +            - can be 6, 8, 10 or 12 on stm32f4
> +            - can be 8, 10, 12, 14 or 16 on stm32h7 and stm32mp1
> +        allOf:
> +          - $ref: /schemas/types.yaml#/definitions/uint32
> +
> +      st,adc-channels:
> +        description: |
> +          List of single-ended channels muxed for this ADC. It can have up to:
> +            - 16 channels, numbered from 0 to 15 (for in0..in15) on stm32f4
> +            - 20 channels, numbered from 0 to 19 (for in0..in19) on stm32h7 and
> +              stm32mp1.
> +        allOf:
> +          - $ref: /schemas/types.yaml#/definitions/uint32-array
> +
> +      st,adc-diff-channels:
> +        description: |
> +          List of differential channels muxed for this ADC. Some channels can
> +          be configured as differential instead of single-ended on stm32h7 and
> +          on stm32mp1. Positive and negative inputs pairs are listed:
> +          <vinp vinn>, <vinp vinn>,... vinp and vinn are numbered from 0 to 19.
> +
> +          Note: At least one of "st,adc-channels" or "st,adc-diff-channels" is
> +          required. Both properties can be used together. Some channels can be
> +          used as single-ended and some other ones as differential (mixed). But
> +          channels can't be configured both as single-ended and differential.
> +        allOf:
> +          - $ref: /schemas/types.yaml#/definitions/uint32-matrix
> +          - items:
> +              items:
> +                - description: |
> +                    "vinp" indicates positive input number
> +                  minimum: 0
> +                  maximum: 19
> +                - description: |
> +                    "vinn" indicates negative input number
> +                  minimum: 0
> +                  maximum: 19
> +
> +      st,min-sample-time-nsecs:
> +        description: |
> +          Minimum sampling time in nanoseconds. Depending on hardware (board)
> +          e.g. high/low analog input source impedance, fine tune of ADC
> +          sampling time may be recommended. This can be either one value or an
> +          array that matches "st,adc-channels" and/or "st,adc-diff-channels"
> +          list, to set sample time resp. for all channels, or independently for
> +          each channel.
> +        allOf:
> +          - $ref: /schemas/types.yaml#/definitions/uint32-array
> +
> +    allOf:
> +      - if:
> +          properties:
> +            compatible:
> +              contains:
> +                const: st,stm32f4-adc

There's a lot of if/thens in this binding. I wonder if splitting this 
into 2 files might be cleaner. 

> +
> +        then:
> +          properties:
> +            reg:
> +              enum:
> +                - 0x0
> +                - 0x100
> +                - 0x200
> +
> +            interrupts:
> +              minimum: 0
> +              maximum: 2
> +
> +            assigned-resolution-bits:
> +              allOf:
> +                - enum: [6, 8, 10, 12]
> +                - default: 12
> +
> +            st,adc-channels:
> +              allOf:
> +                - maxItems: 16
> +                  items:
> +                    minimum: 0
> +                    maximum: 15
> +
> +            st,adc-diff-channels: false
> +
> +            st,min-sample-time-nsecs:
> +              allOf:
> +                - maxItems: 16
> +                  items:
> +                    minimum: 80
> +
> +          required:
> +            - clocks
> +
> +      - if:
> +          properties:
> +            compatible:
> +              contains:
> +                enum:
> +                  - st,stm32h7-adc
> +                  - st,stm32mp1-adc
> +
> +        then:
> +          properties:
> +            reg:
> +              enum:
> +                - 0x0
> +                - 0x100
> +
> +            interrupts:
> +              minimum: 0
> +              maximum: 1
> +
> +            assigned-resolution-bits:
> +              allOf:

Shouldn't need the allOf here.

> +                - enum: [8, 10, 12, 14, 16]
> +                - default: 16
> +
> +            st,adc-channels:
> +              allOf:

Shouldn't need the allOf here.

> +                - maxItems: 20
> +                  items:
> +                    minimum: 0
> +                    maximum: 19
> +
> +            st,min-sample-time-nsecs:
> +              allOf:

Shouldn't need the allOf here.

> +                - maxItems: 20
> +                  items:
> +                    minimum: 40
> +
> +    additionalProperties: false
> +
> +    anyOf:
> +      - required:
> +          - st,adc-channels
> +      - required:
> +          - st,adc-diff-channels
> +
> +    required:
> +      - compatible
> +      - reg
> +      - interrupts
> +      - '#io-channel-cells'
> +
> +examples:
> +  - |
> +    // Example 1: with stm32f429
> +      adc123: adc@40012000 {
> +        compatible = "st,stm32f4-adc-core";
> +        reg = <0x40012000 0x400>;
> +        interrupts = <18>;
> +        clocks = <&rcc 0 168>;
> +        clock-names = "adc";
> +        st,max-clk-rate-hz = <36000000>;
> +        vdda-supply = <&vdda>;
> +        vref-supply = <&vref>;
> +        interrupt-controller;
> +        #interrupt-cells = <1>;
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +        adc@0 {
> +          compatible = "st,stm32f4-adc";
> +          #io-channel-cells = <1>;
> +          reg = <0x0>;
> +          clocks = <&rcc 0 168>;
> +          interrupt-parent = <&adc123>;
> +          interrupts = <0>;
> +          st,adc-channels = <8>;
> +          dmas = <&dma2 0 0 0x400 0x0>;
> +          dma-names = "rx";
> +          assigned-resolution-bits = <8>;
> +        };
> +        // ...
> +        // other adc child nodes follow...
> +      };
> +
> +  - |
> +    // Example 2: with stm32mp157c to setup ADC1 with:
> +    // - channel 1 as single-ended
> +    // - channels 2 & 3 as differential (with resp. 6 & 7 negative inputs)
> +      #include <dt-bindings/interrupt-controller/arm-gic.h>
> +      #include <dt-bindings/clock/stm32mp1-clks.h>
> +      adc12: adc@48003000 {
> +        compatible = "st,stm32mp1-adc-core";
> +        reg = <0x48003000 0x400>;
> +        interrupts = <GIC_SPI 18 IRQ_TYPE_LEVEL_HIGH>,
> +                     <GIC_SPI 90 IRQ_TYPE_LEVEL_HIGH>;
> +        clocks = <&rcc ADC12>, <&rcc ADC12_K>;
> +        clock-names = "bus", "adc";
> +        booster-supply = <&booster>;
> +        vdd-supply = <&vdd>;
> +        vdda-supply = <&vdda>;
> +        vref-supply = <&vref>;
> +        st,syscfg = <&syscfg>;
> +        interrupt-controller;
> +        #interrupt-cells = <1>;
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +        adc@0 {
> +          compatible = "st,stm32mp1-adc";
> +          #io-channel-cells = <1>;
> +          reg = <0x0>;
> +          interrupt-parent = <&adc12>;
> +          interrupts = <0>;
> +          st,adc-channels = <1>;
> +          st,adc-diff-channels = <2 6>, <3 7>;
> +          st,min-sample-time-nsecs = <5000>;
> +          dmas = <&dmamux1 9 0x400 0x05>;
> +          dma-names = "rx";
> +        };
> +        // ...
> +        // other adc child node follow...
> +      };
> +
> +...
> -- 
> 2.7.4
>

Fabrice Gasnier Dec. 6, 2019, 4:18 p.m. UTC | #3

On 12/5/19 11:24 PM, Rob Herring wrote:
> On Wed, Nov 27, 2019 at 05:48:45PM +0100, Fabrice Gasnier wrote:
>> Convert the STM32 ADC binding to DT schema format using json-schema
>>
>> Signed-off-by: Fabrice Gasnier <[e-mail]>
>> ---
>> Note: this applies on top of IIO tree currently (iio-for-5.5c).
>> ---
>>  .../devicetree/bindings/iio/adc/st,stm32-adc.txt   | 149 -------
>>  .../devicetree/bindings/iio/adc/st,stm32-adc.yaml  | 448 +++++++++++++++++++++
>>  2 files changed, 448 insertions(+), 149 deletions(-)
>>  delete mode 100644 Documentation/devicetree/bindings/iio/adc/st,stm32-adc.txt
>>  create mode 100644 Documentation/devicetree/bindings/iio/adc/st,stm32-adc.yaml
> 
> 
>> diff --git a/Documentation/devicetree/bindings/iio/adc/st,stm32-adc.yaml b/Documentation/devicetree/bindings/iio/adc/st,stm32-adc.yaml
>> new file mode 100644
>> index 00000000..2ebc2e6
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/iio/adc/st,stm32-adc.yaml
>> @@ -0,0 +1,448 @@
>> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
>> +%YAML 1.2
>> +---
>> +$id: "http://devicetree.org/schemas/bindings/iio/adc/st,stm32-adc.yaml#"
>> +$schema: "http://devicetree.org/meta-schemas/core.yaml#"
>> +
>> +title: STMicroelectronics STM32 ADC bindings
>> +
>> +description: |
>> +  STM32 ADC is a successive approximation analog-to-digital converter.
>> +  It has several multiplexed input channels. Conversions can be performed
>> +  in single, continuous, scan or discontinuous mode. Result of the ADC is
>> +  stored in a left-aligned or right-aligned 32-bit data register.
>> +  Conversions can be launched in software or using hardware triggers.
>> +
>> +  The analog watchdog feature allows the application to detect if the input
>> +  voltage goes beyond the user-defined, higher or lower thresholds.
>> +
>> +  Each STM32 ADC block can have up to 3 ADC instances.
>> +
>> +maintainers:
>> +  - Fabrice Gasnier <[e-mail]>
>> +
>> +properties:
>> +  compatible:
>> +    enum:
>> +      - st,stm32f4-adc-core
>> +      - st,stm32h7-adc-core
>> +      - st,stm32mp1-adc-core
>> +
>> +  reg:
>> +    description: Offset and length of the ADC block register set
> 
> Don't need generic description of a standard property.

Hi Rob,

ok

> 
>> +    maxItems: 1
>> +
>> +  interrupts:
>> +    description: |
>> +      One or more interrupts for ADC block, depending on part used:
>> +        - stm32f4 and stm32h7 share a common ADC interrupt line.
>> +        - stm32mp1 has two separate interrupt lines, one for each ADC within
>> +          ADC block.
> 
> You can put minItems: 1, maxItems: 2 here.

ok

> 
>> +
>> +  clocks:
>> +    description: |
>> +      Core can use up to two clocks, depending on part used:
>> +        - "adc" clock: for the analog circuitry, common to all ADCs.
>> +          It's required on stm32f4.
>> +          It's optional on stm32h7 and stm32mp1.
>> +        - "bus" clock: for registers access, common to all ADCs.
>> +          It's not present on stm32f4.
>> +          It's required on stm32h7 and stm32mp1.
>> +
>> +  clock-names: true
>> +
>> +  st,max-clk-rate-hz:
>> +    description: |
>> +      Allow to specify desired max clock rate used by analog circuitry.
>> +    allOf:
>> +      - $ref: /schemas/types.yaml#/definitions/uint32
> 
> *-hz already has a type, so you can drop this.
> 
> No range you can specify?

Yes, I'll add it in V2 under the if sections bellow as it depends on the
STM32 device (compatible).

> 
>> +
>> +  vdda-supply:
>> +    description: Phandle to the vdda input analog voltage.
>> +
>> +  vref-supply:
>> +    description: Phandle to the vref input analog reference voltage.
>> +
>> +  booster-supply:
>> +    description: |
> 
> There's not any formatting here, so '|' can be dropped.

ok, I'll remove it also at few places

> 
>> +      Phandle to the embedded booster regulator that can be used to supply ADC
>> +      analog input switches on stm32h7 and stm32mp1.
>> +
>> +  vdd-supply:
>> +    description: |
>> +      Phandle to the vdd input voltage. It can be used to supply ADC analog
>> +      input switches on stm32mp1.
>> +
>> +  st,syscfg:
>> +    description: |
>> +      Phandle to system configuration controller. It can be used to control the
>> +      analog circuitry on stm32mp1.
>> +    allOf:
>> +      - $ref: "/schemas/types.yaml#/definitions/phandle-array"
>> +
>> +  interrupt-controller: true
>> +
>> +  '#interrupt-cells':
>> +    const: 1
>> +
>> +  '#address-cells':
>> +    const: 1
>> +
>> +  '#size-cells':
>> +    const: 0
>> +
>> +allOf:
>> +  - if:
>> +      properties:
>> +        compatible:
>> +          contains:
>> +            const: st,stm32f4-adc-core
>> +
>> +    then:
>> +      properties:
>> +        clocks:
>> +          maxItems: 1
>> +
>> +        clock-names:
>> +          items:
>> +            const: adc
>> +          maxItems: 1
> 
> You can simplify to:
> 
> clock-names:
>   const: adc
> 
> Note that if you did have 'items' it should be a list (i.e. have '-').

ok

> 
>> +
>> +        interrupts:
>> +          items:
>> +            - description: interrupt line common for all ADCs
>> +
>> +        booster-supply: false
>> +
>> +        vdd-supply: false
>> +
>> +        st,syscfg: false
>> +
>> +  - if:
>> +      properties:
>> +        compatible:
>> +          contains:
>> +            const: st,stm32h7-adc-core
>> +
>> +    then:
>> +      properties:
>> +        clocks:
>> +          minItems: 1
>> +          maxItems: 2
>> +
>> +        clock-names:
>> +          items:
>> +            - const: bus
>> +            - const: adc
>> +          minItems: 1
>> +          maxItems: 2
>> +
>> +        interrupts:
>> +          items:
>> +            - description: interrupt line common for all ADCs
>> +
>> +        vdd-supply: false
>> +
>> +        st,syscfg: false
>> +
>> +  - if:
>> +      properties:
>> +        compatible:
>> +          contains:
>> +            const: st,stm32mp1-adc-core
>> +
>> +    then:
>> +      properties:
>> +        clocks:
>> +          minItems: 1
>> +          maxItems: 2
>> +
>> +        clock-names:
>> +          items:
>> +            - const: bus
>> +            - const: adc
>> +          minItems: 1
>> +          maxItems: 2
>> +
>> +        interrupts:
>> +          items:
>> +            - description: interrupt line for ADC1
>> +            - description: interrupt line for ADC2
>> +
>> +additionalProperties: false
>> +
>> +required:
>> +  - compatible
>> +  - reg
>> +  - interrupts
>> +  - clocks
>> +  - clock-names
>> +  - vdda-supply
>> +  - vref-supply
>> +  - interrupt-controller
>> +  - '#interrupt-cells'
>> +  - '#address-cells'
>> +  - '#size-cells'
>> +
>> +patternProperties:
>> +  "^adc@[0-9]+$":
>> +    type: object
>> +    description: |
>> +      An ADC block node should contain at least one subnode, representing an
>> +      ADC instance available on the machine.
>> +
>> +    properties:
>> +      compatible:
>> +        enum:
>> +          - st,stm32f4-adc
>> +          - st,stm32h7-adc
>> +          - st,stm32mp1-adc
>> +
>> +      reg:
>> +        description: |
>> +          Offset of ADC instance in ADC block. Valid values are:
>> +            - 0x0:   ADC1
>> +            - 0x100: ADC2
>> +            - 0x200: ADC3 (stm32f4 only)
>> +        maxItems: 1
>> +
>> +      '#io-channel-cells':
>> +        const: 1
>> +
>> +      interrupts:
>> +        description: |
>> +          IRQ Line for the ADC instance. Valid values are:
>> +            - 0 for adc@0
>> +            - 1 for adc@100
>> +            - 2 for adc@200 (stm32f4 only)
>> +        maxItems: 1
>> +
>> +      clocks:
>> +        description: |
>> +          Input clock private to this ADC instance. It's required only on
>> +          stm32f4, that has per instance clock input for registers access.
>> +        maxItems: 1
>> +
>> +      dmas:
>> +        description: RX DMA Channel
>> +        maxItems: 1
>> +
>> +      dma-names:
>> +        const: rx
>> +
>> +      assigned-resolution-bits:
>> +        description: |
>> +          Resolution (bits) to use for conversions:
>> +            - can be 6, 8, 10 or 12 on stm32f4
>> +            - can be 8, 10, 12, 14 or 16 on stm32h7 and stm32mp1
>> +        allOf:
>> +          - $ref: /schemas/types.yaml#/definitions/uint32
>> +
>> +      st,adc-channels:
>> +        description: |
>> +          List of single-ended channels muxed for this ADC. It can have up to:
>> +            - 16 channels, numbered from 0 to 15 (for in0..in15) on stm32f4
>> +            - 20 channels, numbered from 0 to 19 (for in0..in19) on stm32h7 and
>> +              stm32mp1.
>> +        allOf:
>> +          - $ref: /schemas/types.yaml#/definitions/uint32-array
>> +
>> +      st,adc-diff-channels:
>> +        description: |
>> +          List of differential channels muxed for this ADC. Some channels can
>> +          be configured as differential instead of single-ended on stm32h7 and
>> +          on stm32mp1. Positive and negative inputs pairs are listed:
>> +          <vinp vinn>, <vinp vinn>,... vinp and vinn are numbered from 0 to 19.
>> +
>> +          Note: At least one of "st,adc-channels" or "st,adc-diff-channels" is
>> +          required. Both properties can be used together. Some channels can be
>> +          used as single-ended and some other ones as differential (mixed). But
>> +          channels can't be configured both as single-ended and differential.
>> +        allOf:
>> +          - $ref: /schemas/types.yaml#/definitions/uint32-matrix
>> +          - items:
>> +              items:
>> +                - description: |
>> +                    "vinp" indicates positive input number
>> +                  minimum: 0
>> +                  maximum: 19
>> +                - description: |
>> +                    "vinn" indicates negative input number
>> +                  minimum: 0
>> +                  maximum: 19
>> +
>> +      st,min-sample-time-nsecs:
>> +        description: |
>> +          Minimum sampling time in nanoseconds. Depending on hardware (board)
>> +          e.g. high/low analog input source impedance, fine tune of ADC
>> +          sampling time may be recommended. This can be either one value or an
>> +          array that matches "st,adc-channels" and/or "st,adc-diff-channels"
>> +          list, to set sample time resp. for all channels, or independently for
>> +          each channel.
>> +        allOf:
>> +          - $ref: /schemas/types.yaml#/definitions/uint32-array
>> +
>> +    allOf:
>> +      - if:
>> +          properties:
>> +            compatible:
>> +              contains:
>> +                const: st,stm32f4-adc
> 
> There's a lot of if/thens in this binding. I wonder if splitting this 
> into 2 files might be cleaner. 

Indeed there are a lot of these... But there is also several common
descriptions (the core remains similar).
Do you mind if I keep it that way ?

Let's discuss that in V2 otherwise.
In case we're going to split this:
- I think the most similar ADCs are STM32H7 and STM32MP1
- The STM32F4 ADC bindings should then be apart.

> 
>> +
>> +        then:
>> +          properties:
>> +            reg:
>> +              enum:
>> +                - 0x0
>> +                - 0x100
>> +                - 0x200
>> +
>> +            interrupts:
>> +              minimum: 0
>> +              maximum: 2
>> +
>> +            assigned-resolution-bits:
>> +              allOf:
>> +                - enum: [6, 8, 10, 12]
>> +                - default: 12
>> +
>> +            st,adc-channels:
>> +              allOf:
>> +                - maxItems: 16
>> +                  items:
>> +                    minimum: 0
>> +                    maximum: 15
>> +
>> +            st,adc-diff-channels: false
>> +
>> +            st,min-sample-time-nsecs:
>> +              allOf:
>> +                - maxItems: 16
>> +                  items:
>> +                    minimum: 80
>> +
>> +          required:
>> +            - clocks
>> +
>> +      - if:
>> +          properties:
>> +            compatible:
>> +              contains:
>> +                enum:
>> +                  - st,stm32h7-adc
>> +                  - st,stm32mp1-adc
>> +
>> +        then:
>> +          properties:
>> +            reg:
>> +              enum:
>> +                - 0x0
>> +                - 0x100
>> +
>> +            interrupts:
>> +              minimum: 0
>> +              maximum: 1
>> +
>> +            assigned-resolution-bits:
>> +              allOf:
> 
> Shouldn't need the allOf here.

ok

> 
>> +                - enum: [8, 10, 12, 14, 16]
>> +                - default: 16
>> +
>> +            st,adc-channels:
>> +              allOf:
> 
> Shouldn't need the allOf here.

ok

> 
>> +                - maxItems: 20
>> +                  items:
>> +                    minimum: 0
>> +                    maximum: 19
>> +
>> +            st,min-sample-time-nsecs:
>> +              allOf:
> 
> Shouldn't need the allOf here.

ok

> 
>> +                - maxItems: 20
>> +                  items:
>> +                    minimum: 40
>> +
>> +    additionalProperties: false
>> +
>> +    anyOf:
>> +      - required:
>> +          - st,adc-channels
>> +      - required:
>> +          - st,adc-diff-channels
>> +
>> +    required:
>> +      - compatible
>> +      - reg
>> +      - interrupts
>> +      - '#io-channel-cells'
>> +
>> +examples:
>> +  - |
>> +    // Example 1: with stm32f429
>> +      adc123: adc@40012000 {
>> +        compatible = "st,stm32f4-adc-core";
>> +        reg = <0x40012000 0x400>;
>> +        interrupts = <18>;
>> +        clocks = <&rcc 0 168>;
>> +        clock-names = "adc";
>> +        st,max-clk-rate-hz = <36000000>;
>> +        vdda-supply = <&vdda>;
>> +        vref-supply = <&vref>;
>> +        interrupt-controller;
>> +        #interrupt-cells = <1>;
>> +        #address-cells = <1>;
>> +        #size-cells = <0>;
>> +        adc@0 {
>> +          compatible = "st,stm32f4-adc";
>> +          #io-channel-cells = <1>;
>> +          reg = <0x0>;
>> +          clocks = <&rcc 0 168>;
>> +          interrupt-parent = <&adc123>;
>> +          interrupts = <0>;
>> +          st,adc-channels = <8>;
>> +          dmas = <&dma2 0 0 0x400 0x0>;
>> +          dma-names = "rx";
>> +          assigned-resolution-bits = <8>;
>> +        };
>> +        // ...
>> +        // other adc child nodes follow...
>> +      };
>> +
>> +  - |
>> +    // Example 2: with stm32mp157c to setup ADC1 with:
>> +    // - channel 1 as single-ended
>> +    // - channels 2 & 3 as differential (with resp. 6 & 7 negative inputs)
>> +      #include <dt-bindings/interrupt-controller/arm-gic.h>
>> +      #include <dt-bindings/clock/stm32mp1-clks.h>
>> +      adc12: adc@48003000 {
>> +        compatible = "st,stm32mp1-adc-core";
>> +        reg = <0x48003000 0x400>;
>> +        interrupts = <GIC_SPI 18 IRQ_TYPE_LEVEL_HIGH>,
>> +                     <GIC_SPI 90 IRQ_TYPE_LEVEL_HIGH>;
>> +        clocks = <&rcc ADC12>, <&rcc ADC12_K>;
>> +        clock-names = "bus", "adc";
>> +        booster-supply = <&booster>;
>> +        vdd-supply = <&vdd>;
>> +        vdda-supply = <&vdda>;
>> +        vref-supply = <&vref>;
>> +        st,syscfg = <&syscfg>;
>> +        interrupt-controller;
>> +        #interrupt-cells = <1>;
>> +        #address-cells = <1>;
>> +        #size-cells = <0>;
>> +        adc@0 {
>> +          compatible = "st,stm32mp1-adc";
>> +          #io-channel-cells = <1>;
>> +          reg = <0x0>;
>> +          interrupt-parent = <&adc12>;
>> +          interrupts = <0>;
>> +          st,adc-channels = <1>;
>> +          st,adc-diff-channels = <2 6>, <3 7>;
>> +          st,min-sample-time-nsecs = <5000>;
>> +          dmas = <&dmamux1 9 0x400 0x05>;
>> +          dma-names = "rx";
>> +        };
>> +        // ...
>> +        // other adc child node follow...
>> +      };
>> +
>> +...
>> -- 
>> 2.7.4
>>

Patch

diff --git a/Documentation/devicetree/bindings/iio/adc/st,stm32-adc.txt b/Documentation/devicetree/bindings/iio/adc/st,stm32-adc.txt
deleted file mode 100644
index 8de9331..00000000
--- a/Documentation/devicetree/bindings/iio/adc/st,stm32-adc.txt
+++ /dev/null
@@ -1,149 +0,0 @@ 
-STMicroelectronics STM32 ADC device driver
-
-STM32 ADC is a successive approximation analog-to-digital converter.
-It has several multiplexed input channels. Conversions can be performed
-in single, continuous, scan or discontinuous mode. Result of the ADC is
-stored in a left-aligned or right-aligned 32-bit data register.
-Conversions can be launched in software or using hardware triggers.
-
-The analog watchdog feature allows the application to detect if the input
-voltage goes beyond the user-defined, higher or lower thresholds.
-
-Each STM32 ADC block can have up to 3 ADC instances.
-
-Each instance supports two contexts to manage conversions, each one has its
-own configurable sequence and trigger:
-- regular conversion can be done in sequence, running in background
-- injected conversions have higher priority, and so have the ability to
-  interrupt regular conversion sequence (either triggered in SW or HW).
-  Regular sequence is resumed, in case it has been interrupted.
-
-Contents of a stm32 adc root node:
------------------------------------
-Required properties:
-- compatible: Should be one of:
-  "st,stm32f4-adc-core"
-  "st,stm32h7-adc-core"
-  "st,stm32mp1-adc-core"
-- reg: Offset and length of the ADC block register set.
-- interrupts: One or more interrupts for ADC block. Some parts like stm32f4
-  and stm32h7 share a common ADC interrupt line. stm32mp1 has two separate
-  interrupt lines, one for each ADC within ADC block.
-- clocks: Core can use up to two clocks, depending on part used:
-  - "adc" clock: for the analog circuitry, common to all ADCs.
-    It's required on stm32f4.
-    It's optional on stm32h7.
-  - "bus" clock: for registers access, common to all ADCs.
-    It's not present on stm32f4.
-    It's required on stm32h7.
-- clock-names: Must be "adc" and/or "bus" depending on part used.
-- interrupt-controller: Identifies the controller node as interrupt-parent
-- vdda-supply: Phandle to the vdda input analog voltage.
-- vref-supply: Phandle to the vref input analog reference voltage.
-- #interrupt-cells = <1>;
-- #address-cells = <1>;
-- #size-cells = <0>;
-
-Optional properties:
-- A pinctrl state named "default" for each ADC channel may be defined to set
-  inX ADC pins in mode of operation for analog input on external pin.
-- booster-supply: Phandle to the embedded booster regulator that can be used
-  to supply ADC analog input switches on stm32h7 and stm32mp1.
-- vdd-supply: Phandle to the vdd input voltage. It can be used to supply ADC
-  analog input switches on stm32mp1.
-- st,syscfg: Phandle to system configuration controller. It can be used to
-  control the analog circuitry on stm32mp1.
-- st,max-clk-rate-hz: Allow to specify desired max clock rate used by analog
-  circuitry.
-
-Contents of a stm32 adc child node:
------------------------------------
-An ADC block node should contain at least one subnode, representing an
-ADC instance available on the machine.
-
-Required properties:
-- compatible: Should be one of:
-  "st,stm32f4-adc"
-  "st,stm32h7-adc"
-  "st,stm32mp1-adc"
-- reg: Offset of ADC instance in ADC block (e.g. may be 0x0, 0x100, 0x200).
-- clocks: Input clock private to this ADC instance. It's required only on
-  stm32f4, that has per instance clock input for registers access.
-- interrupts: IRQ Line for the ADC (e.g. may be 0 for adc@0, 1 for adc@100 or
-  2 for adc@200).
-- st,adc-channels: List of single-ended channels muxed for this ADC.
-  It can have up to 16 channels on stm32f4 or 20 channels on stm32h7, numbered
-  from 0 to 15 or 19 (resp. for in0..in15 or in0..in19).
-- st,adc-diff-channels: List of differential channels muxed for this ADC.
-  Depending on part used, some channels can be configured as differential
-  instead of single-ended (e.g. stm32h7). List here positive and negative
-  inputs pairs as <vinp vinn>, <vinp vinn>,... vinp and vinn are numbered
-  from 0 to 19 on stm32h7)
-  Note: At least one of "st,adc-channels" or "st,adc-diff-channels" is required.
-  Both properties can be used together. Some channels can be used as
-  single-ended and some other ones as differential (mixed). But channels
-  can't be configured both as single-ended and differential (invalid).
-- #io-channel-cells = <1>: See the IIO bindings section "IIO consumers" in
-  Documentation/devicetree/bindings/iio/iio-bindings.txt
-
-Optional properties:
-- dmas: Phandle to dma channel for this ADC instance.
-  See ../../dma/dma.txt for details.
-- dma-names: Must be "rx" when dmas property is being used.
-- assigned-resolution-bits: Resolution (bits) to use for conversions. Must
-  match device available resolutions:
-  * can be 6, 8, 10 or 12 on stm32f4
-  * can be 8, 10, 12, 14 or 16 on stm32h7
-  Default is maximum resolution if unset.
-- st,min-sample-time-nsecs: Minimum sampling time in nanoseconds.
-  Depending on hardware (board) e.g. high/low analog input source impedance,
-  fine tune of ADC sampling time may be recommended.
-  This can be either one value or an array that matches 'st,adc-channels' list,
-  to set sample time resp. for all channels, or independently for each channel.
-
-Example:
-	adc: adc@40012000 {
-		compatible = "st,stm32f4-adc-core";
-		reg = <0x40012000 0x400>;
-		interrupts = <18>;
-		clocks = <&rcc 0 168>;
-		clock-names = "adc";
-		vref-supply = <&reg_vref>;
-		interrupt-controller;
-		pinctrl-names = "default";
-		pinctrl-0 = <&adc3_in8_pin>;
-
-		#interrupt-cells = <1>;
-		#address-cells = <1>;
-		#size-cells = <0>;
-
-		adc@0 {
-			compatible = "st,stm32f4-adc";
-			#io-channel-cells = <1>;
-			reg = <0x0>;
-			clocks = <&rcc 0 168>;
-			interrupt-parent = <&adc>;
-			interrupts = <0>;
-			st,adc-channels = <8>;
-			dmas = <&dma2 0 0 0x400 0x0>;
-			dma-names = "rx";
-			assigned-resolution-bits = <8>;
-		};
-		...
-		other adc child nodes follow...
-	};
-
-Example to setup:
-- channel 1 as single-ended
-- channels 2 & 3 as differential (with resp. 6 & 7 negative inputs)
-
-	adc: adc@40022000 {
-		compatible = "st,stm32h7-adc-core";
-		...
-		adc1: adc@0 {
-			compatible = "st,stm32h7-adc";
-			...
-			st,adc-channels = <1>;
-			st,adc-diff-channels = <2 6>, <3 7>;
-		};
-	};
diff --git a/Documentation/devicetree/bindings/iio/adc/st,stm32-adc.yaml b/Documentation/devicetree/bindings/iio/adc/st,stm32-adc.yaml
new file mode 100644
index 00000000..2ebc2e6
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/adc/st,stm32-adc.yaml
@@ -0,0 +1,448 @@ 
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: "http://devicetree.org/schemas/bindings/iio/adc/st,stm32-adc.yaml#"
+$schema: "http://devicetree.org/meta-schemas/core.yaml#"
+
+title: STMicroelectronics STM32 ADC bindings
+
+description: |
+  STM32 ADC is a successive approximation analog-to-digital converter.
+  It has several multiplexed input channels. Conversions can be performed
+  in single, continuous, scan or discontinuous mode. Result of the ADC is
+  stored in a left-aligned or right-aligned 32-bit data register.
+  Conversions can be launched in software or using hardware triggers.
+
+  The analog watchdog feature allows the application to detect if the input
+  voltage goes beyond the user-defined, higher or lower thresholds.
+
+  Each STM32 ADC block can have up to 3 ADC instances.
+
+maintainers:
+  - Fabrice Gasnier <[e-mail]>
+
+properties:
+  compatible:
+    enum:
+      - st,stm32f4-adc-core
+      - st,stm32h7-adc-core
+      - st,stm32mp1-adc-core
+
+  reg:
+    description: Offset and length of the ADC block register set
+    maxItems: 1
+
+  interrupts:
+    description: |
+      One or more interrupts for ADC block, depending on part used:
+        - stm32f4 and stm32h7 share a common ADC interrupt line.
+        - stm32mp1 has two separate interrupt lines, one for each ADC within
+          ADC block.
+
+  clocks:
+    description: |
+      Core can use up to two clocks, depending on part used:
+        - "adc" clock: for the analog circuitry, common to all ADCs.
+          It's required on stm32f4.
+          It's optional on stm32h7 and stm32mp1.
+        - "bus" clock: for registers access, common to all ADCs.
+          It's not present on stm32f4.
+          It's required on stm32h7 and stm32mp1.
+
+  clock-names: true
+
+  st,max-clk-rate-hz:
+    description: |
+      Allow to specify desired max clock rate used by analog circuitry.
+    allOf:
+      - $ref: /schemas/types.yaml#/definitions/uint32
+
+  vdda-supply:
+    description: Phandle to the vdda input analog voltage.
+
+  vref-supply:
+    description: Phandle to the vref input analog reference voltage.
+
+  booster-supply:
+    description: |
+      Phandle to the embedded booster regulator that can be used to supply ADC
+      analog input switches on stm32h7 and stm32mp1.
+
+  vdd-supply:
+    description: |
+      Phandle to the vdd input voltage. It can be used to supply ADC analog
+      input switches on stm32mp1.
+
+  st,syscfg:
+    description: |
+      Phandle to system configuration controller. It can be used to control the
+      analog circuitry on stm32mp1.
+    allOf:
+      - $ref: "/schemas/types.yaml#/definitions/phandle-array"
+
+  interrupt-controller: true
+
+  '#interrupt-cells':
+    const: 1
+
+  '#address-cells':
+    const: 1
+
+  '#size-cells':
+    const: 0
+
+allOf:
+  - if:
+      properties:
+        compatible:
+          contains:
+            const: st,stm32f4-adc-core
+
+    then:
+      properties:
+        clocks:
+          maxItems: 1
+
+        clock-names:
+          items:
+            const: adc
+          maxItems: 1
+
+        interrupts:
+          items:
+            - description: interrupt line common for all ADCs
+
+        booster-supply: false
+
+        vdd-supply: false
+
+        st,syscfg: false
+
+  - if:
+      properties:
+        compatible:
+          contains:
+            const: st,stm32h7-adc-core
+
+    then:
+      properties:
+        clocks:
+          minItems: 1
+          maxItems: 2
+
+        clock-names:
+          items:
+            - const: bus
+            - const: adc
+          minItems: 1
+          maxItems: 2
+
+        interrupts:
+          items:
+            - description: interrupt line common for all ADCs
+
+        vdd-supply: false
+
+        st,syscfg: false
+
+  - if:
+      properties:
+        compatible:
+          contains:
+            const: st,stm32mp1-adc-core
+
+    then:
+      properties:
+        clocks:
+          minItems: 1
+          maxItems: 2
+
+        clock-names:
+          items:
+            - const: bus
+            - const: adc
+          minItems: 1
+          maxItems: 2
+
+        interrupts:
+          items:
+            - description: interrupt line for ADC1
+            - description: interrupt line for ADC2
+
+additionalProperties: false
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - clocks
+  - clock-names
+  - vdda-supply
+  - vref-supply
+  - interrupt-controller
+  - '#interrupt-cells'
+  - '#address-cells'
+  - '#size-cells'
+
+patternProperties:
+  "^adc@[0-9]+$":
+    type: object
+    description: |
+      An ADC block node should contain at least one subnode, representing an
+      ADC instance available on the machine.
+
+    properties:
+      compatible:
+        enum:
+          - st,stm32f4-adc
+          - st,stm32h7-adc
+          - st,stm32mp1-adc
+
+      reg:
+        description: |
+          Offset of ADC instance in ADC block. Valid values are:
+            - 0x0:   ADC1
+            - 0x100: ADC2
+            - 0x200: ADC3 (stm32f4 only)
+        maxItems: 1
+
+      '#io-channel-cells':
+        const: 1
+
+      interrupts:
+        description: |
+          IRQ Line for the ADC instance. Valid values are:
+            - 0 for adc@0
+            - 1 for adc@100
+            - 2 for adc@200 (stm32f4 only)
+        maxItems: 1
+
+      clocks:
+        description: |
+          Input clock private to this ADC instance. It's required only on
+          stm32f4, that has per instance clock input for registers access.
+        maxItems: 1
+
+      dmas:
+        description: RX DMA Channel
+        maxItems: 1
+
+      dma-names:
+        const: rx
+
+      assigned-resolution-bits:
+        description: |
+          Resolution (bits) to use for conversions:
+            - can be 6, 8, 10 or 12 on stm32f4
+            - can be 8, 10, 12, 14 or 16 on stm32h7 and stm32mp1
+        allOf:
+          - $ref: /schemas/types.yaml#/definitions/uint32
+
+      st,adc-channels:
+        description: |
+          List of single-ended channels muxed for this ADC. It can have up to:
+            - 16 channels, numbered from 0 to 15 (for in0..in15) on stm32f4
+            - 20 channels, numbered from 0 to 19 (for in0..in19) on stm32h7 and
+              stm32mp1.
+        allOf:
+          - $ref: /schemas/types.yaml#/definitions/uint32-array
+
+      st,adc-diff-channels:
+        description: |
+          List of differential channels muxed for this ADC. Some channels can
+          be configured as differential instead of single-ended on stm32h7 and
+          on stm32mp1. Positive and negative inputs pairs are listed:
+          <vinp vinn>, <vinp vinn>,... vinp and vinn are numbered from 0 to 19.
+
+          Note: At least one of "st,adc-channels" or "st,adc-diff-channels" is
+          required. Both properties can be used together. Some channels can be
+          used as single-ended and some other ones as differential (mixed). But
+          channels can't be configured both as single-ended and differential.
+        allOf:
+          - $ref: /schemas/types.yaml#/definitions/uint32-matrix
+          - items:
+              items:
+                - description: |
+                    "vinp" indicates positive input number
+                  minimum: 0
+                  maximum: 19
+                - description: |
+                    "vinn" indicates negative input number
+                  minimum: 0
+                  maximum: 19
+
+      st,min-sample-time-nsecs:
+        description: |
+          Minimum sampling time in nanoseconds. Depending on hardware (board)
+          e.g. high/low analog input source impedance, fine tune of ADC
+          sampling time may be recommended. This can be either one value or an
+          array that matches "st,adc-channels" and/or "st,adc-diff-channels"
+          list, to set sample time resp. for all channels, or independently for
+          each channel.
+        allOf:
+          - $ref: /schemas/types.yaml#/definitions/uint32-array
+
+    allOf:
+      - if:
+          properties:
+            compatible:
+              contains:
+                const: st,stm32f4-adc
+
+        then:
+          properties:
+            reg:
+              enum:
+                - 0x0
+                - 0x100
+                - 0x200
+
+            interrupts:
+              minimum: 0
+              maximum: 2
+
+            assigned-resolution-bits:
+              allOf:
+                - enum: [6, 8, 10, 12]
+                - default: 12
+
+            st,adc-channels:
+              allOf:
+                - maxItems: 16
+                  items:
+                    minimum: 0
+                    maximum: 15
+
+            st,adc-diff-channels: false
+
+            st,min-sample-time-nsecs:
+              allOf:
+                - maxItems: 16
+                  items:
+                    minimum: 80
+
+          required:
+            - clocks
+
+      - if:
+          properties:
+            compatible:
+              contains:
+                enum:
+                  - st,stm32h7-adc
+                  - st,stm32mp1-adc
+
+        then:
+          properties:
+            reg:
+              enum:
+                - 0x0
+                - 0x100
+
+            interrupts:
+              minimum: 0
+              maximum: 1
+
+            assigned-resolution-bits:
+              allOf:
+                - enum: [8, 10, 12, 14, 16]
+                - default: 16
+
+            st,adc-channels:
+              allOf:
+                - maxItems: 20
+                  items:
+                    minimum: 0
+                    maximum: 19
+
+            st,min-sample-time-nsecs:
+              allOf:
+                - maxItems: 20
+                  items:
+                    minimum: 40
+
+    additionalProperties: false
+
+    anyOf:
+      - required:
+          - st,adc-channels
+      - required:
+          - st,adc-diff-channels
+
+    required:
+      - compatible
+      - reg
+      - interrupts
+      - '#io-channel-cells'
+
+examples:
+  - |
+    // Example 1: with stm32f429
+      adc123: adc@40012000 {
+        compatible = "st,stm32f4-adc-core";
+        reg = <0x40012000 0x400>;
+        interrupts = <18>;
+        clocks = <&rcc 0 168>;
+        clock-names = "adc";
+        st,max-clk-rate-hz = <36000000>;
+        vdda-supply = <&vdda>;
+        vref-supply = <&vref>;
+        interrupt-controller;
+        #interrupt-cells = <1>;
+        #address-cells = <1>;
+        #size-cells = <0>;
+        adc@0 {
+          compatible = "st,stm32f4-adc";
+          #io-channel-cells = <1>;
+          reg = <0x0>;
+          clocks = <&rcc 0 168>;
+          interrupt-parent = <&adc123>;
+          interrupts = <0>;
+          st,adc-channels = <8>;
+          dmas = <&dma2 0 0 0x400 0x0>;
+          dma-names = "rx";
+          assigned-resolution-bits = <8>;
+        };
+        // ...
+        // other adc child nodes follow...
+      };
+
+  - |
+    // Example 2: with stm32mp157c to setup ADC1 with:
+    // - channel 1 as single-ended
+    // - channels 2 & 3 as differential (with resp. 6 & 7 negative inputs)
+      #include <dt-bindings/interrupt-controller/arm-gic.h>
+      #include <dt-bindings/clock/stm32mp1-clks.h>
+      adc12: adc@48003000 {
+        compatible = "st,stm32mp1-adc-core";
+        reg = <0x48003000 0x400>;
+        interrupts = <GIC_SPI 18 IRQ_TYPE_LEVEL_HIGH>,
+                     <GIC_SPI 90 IRQ_TYPE_LEVEL_HIGH>;
+        clocks = <&rcc ADC12>, <&rcc ADC12_K>;
+        clock-names = "bus", "adc";
+        booster-supply = <&booster>;
+        vdd-supply = <&vdd>;
+        vdda-supply = <&vdda>;
+        vref-supply = <&vref>;
+        st,syscfg = <&syscfg>;
+        interrupt-controller;
+        #interrupt-cells = <1>;
+        #address-cells = <1>;
+        #size-cells = <0>;
+        adc@0 {
+          compatible = "st,stm32mp1-adc";
+          #io-channel-cells = <1>;
+          reg = <0x0>;
+          interrupt-parent = <&adc12>;
+          interrupts = <0>;
+          st,adc-channels = <1>;
+          st,adc-diff-channels = <2 6>, <3 7>;
+          st,min-sample-time-nsecs = <5000>;
+          dmas = <&dmamux1 9 0x400 0x05>;
+          dma-names = "rx";
+        };
+        // ...
+        // other adc child node follow...
+      };
+
+...