Re: [PATCH v4 1/3] dt-bindings: iio: adc: add AD4695 and similar ADCs

[Rob Herring]

On Thu, Jul 11, 2024 at 1:16 PM David Lechner <dlechner@xxxxxxxxxxxx> wrote:
>
> Add device tree bindings for AD4695 and similar ADCs.
>
> Reviewed-by: Conor Dooley <conor.dooley@xxxxxxxxxxxxx>
> Signed-off-by: David Lechner <dlechner@xxxxxxxxxxxx>
> ---
>
> Note, this may trigger a DT build warning "common-mode-channel: missing
> type definition" if the builder doesn't include the recently added
> common-mode-channel property [1]. This should be safe to ignore (passes
> make dt_binding_check locally).
>
> [1] https://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio.git/commit/?h=testing&id=d86deaec1c5b0fb60c3619e8d2ae7a1d722fd2ad
>
> v4 changes:
> * Picked up Conor's reviewed-by tag.
>
> v3 changes:
> * Change interrupts to be per pin instead of per signal.
> * Drop diff-channels and single-channel properties.
> * Odd numbered pins added to common-mode-channel property enum.
> * REFGND and COM values changes to avoid confusion with pin numbers.
> * Add inX-supply properties for odd numbed input pins.
>
> v2 changes:
> * Drop *-wlcsp compatible strings
> * Don't use fallback compatible strings
> * Reword supply descriptions
> * Use standard channel properties instead of adi,pin-pairing
> * Fix unnecessary | character
> * Fix missing blank line
> * Add header file with common mode channel macros
> ---
>  .../devicetree/bindings/iio/adc/adi,ad4695.yaml    | 256 +++++++++++++++++++++
>  MAINTAINERS                                        |  10 +
>  include/dt-bindings/iio/adi,ad4695.h               |   9 +
>  3 files changed, 275 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/iio/adc/adi,ad4695.yaml b/Documentation/devicetree/bindings/iio/adc/adi,ad4695.yaml
> new file mode 100644
> index 000000000000..a2e824e26691
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/iio/adc/adi,ad4695.yaml
> @@ -0,0 +1,256 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/iio/adc/adi,ad4695.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Analog Devices Easy Drive Multiplexed SAR Analog to Digital Converters
> +
> +maintainers:
> +  - Michael Hennerich <Michael.Hennerich@xxxxxxxxxx>
> +  - Nuno Sá <nuno.sa@xxxxxxxxxx>
> +
> +description: |
> +  A family of similar multi-channel analog to digital converters with SPI bus.
> +
> +  * https://www.analog.com/en/products/ad4695.html
> +  * https://www.analog.com/en/products/ad4696.html
> +  * https://www.analog.com/en/products/ad4697.html
> +  * https://www.analog.com/en/products/ad4698.html
> +
> +$ref: /schemas/spi/spi-peripheral-props.yaml#
> +
> +properties:
> +  compatible:
> +    enum:
> +      - adi,ad4695
> +      - adi,ad4696
> +      - adi,ad4697
> +      - adi,ad4698
> +
> +  reg:
> +    maxItems: 1
> +
> +  spi-max-frequency:
> +    maximum: 80000000
> +
> +  spi-cpol: true
> +  spi-cpha: true
> +
> +  spi-rx-bus-width:
> +    minimum: 1
> +    maximum: 4
> +
> +  avdd-supply:
> +    description: Analog power supply.
> +
> +  vio-supply:
> +    description: I/O pin power supply.
> +
> +  ldo-in-supply:
> +    description: Internal LDO Input. Mutually exclusive with vdd-supply.
> +
> +  vdd-supply:
> +    description: Core power supply. Mutually exclusive with ldo-in-supply.
> +
> +  ref-supply:
> +    description:
> +      External reference voltage. Mutually exclusive with refin-supply.
> +
> +  refin-supply:
> +    description:
> +      Internal reference buffer input. Mutually exclusive with ref-supply.
> +
> +  com-supply:
> +    description: Common voltage supply for pseudo-differential analog inputs.
> +
> +  adi,no-ref-current-limit:
> +    $ref: /schemas/types.yaml#/definitions/flag
> +    description:
> +      When this flag is present, the REF Overvoltage Reduced Current protection
> +      is disabled.
> +
> +  adi,no-ref-high-z:
> +    $ref: /schemas/types.yaml#/definitions/flag
> +    description:
> +      Enable this flag if the ref-supply requires Reference Input High-Z Mode
> +      to be disabled for proper operation.
> +
> +  cnv-gpios:
> +    description: The Convert Input (CNV). If omitted, CNV is tied to SPI CS.
> +    maxItems: 1
> +
> +  reset-gpios:
> +    description: The Reset Input (RESET). Should be configured GPIO_ACTIVE_LOW.
> +    maxItems: 1
> +
> +  interrupts:
> +    minItems: 1
> +    items:
> +      - description: Signal coming from the BSY_ALT_GP0 pin (ALERT or BUSY).
> +      - description: Signal coming from the GP2 pin (ALERT).
> +      - description: Signal coming from the GP3 pin (BUSY).
> +
> +  interrupt-names:
> +    minItems: 1
> +    items:
> +      - const: gp0
> +      - const: gp2
> +      - const: gp3
> +
> +  gpio-controller: true
> +
> +  "#gpio-cells":
> +    const: 2
> +    description: |
> +      The first cell is the GPn number: 0 to 3.
> +      The second cell takes standard GPIO flags.
> +
> +  "#address-cells":
> +    const: 1
> +
> +  "#size-cells":
> +    const: 0
> +
> +patternProperties:
> +  "^in(?:[13579]|1[135])-supply$":
> +    description:
> +      Optional voltage supply for odd numbered channels when they are used as
> +      the negative input for a pseudo-differential channel.
> +
> +  "^channel@[0-9a-f]$":
> +    type: object
> +    $ref: adc.yaml
> +    unevaluatedProperties: false
> +    description:
> +      Describes each individual channel. In addition the properties defined
> +      below, bipolar from adc.yaml is also supported.
> +
> +    properties:
> +      reg:
> +        maximum: 15
> +
> +      common-mode-channel:
> +        description:
> +          Describes the common mode channel for single channels. 0xFF is REFGND
> +          and OxFE is COM. Macros are available for these values in
> +          dt-bindings/iio/adi,ad4695.h. Values 1 to 15 correspond to INx inputs.
> +          Only odd numbered INx inputs can be used as common mode channels.
> +        items:

"items" is for arrays, but common-mode-channel is a uint32. Drop
"items". Either Jonathan can fixup or you'll need to send a fix.

It's now warning in linux-next (you need dtschema main branch):
/builds/robherring/linux-dt/Documentation/devicetree/bindings/iio/adc/adi,ad4695.example.dtb:
adc@0: channel@1:common-mode-channel: 254 is not of type 'array'
        from schema $id: http://devicetree.org/schemas/iio/adc/adi,ad4695.yaml#
/builds/robherring/linux-dt/Documentation/devicetree/bindings/iio/adc/adi,ad4695.example.dtb:
adc@0: channel@2:common-mode-channel: 3 is not of type 'array'
        from schema $id: http://devicetree.org/schemas/iio/adc/adi,ad4695.yaml#

> +          enum: [1, 3, 5, 7, 9, 11, 13, 15, 0xFE, 0xFF]
> +        default: 0xFF

Rob