Re: [PATCH v3 1/3] dt-bindings: iio: adc: Add AD4134

[Tomas Melin <tomas.melin@vaisala.com>]

Hi,

On 02/12/2025 22:55, Marcelo Schmitt wrote:
> Add device tree documentation for AD4134 24-Bit, 4-channel simultaneous
> sampling, precision ADC.
> 
> Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
> Signed-off-by: Marcelo Schmitt <marcelo.schmitt@analog.com>
> ---
> Change log v2 -> v3:
> - fixed typo in powerdown-gpios description.
> - picked up Conor's review tag. 
> 
>  .../bindings/iio/adc/adi,ad4134.yaml          | 198 ++++++++++++++++++
>  MAINTAINERS                                   |   7 +
>  2 files changed, 205 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/iio/adc/adi,ad4134.yaml
> 
> diff --git a/Documentation/devicetree/bindings/iio/adc/adi,ad4134.yaml b/Documentation/devicetree/bindings/iio/adc/adi,ad4134.yaml
> new file mode 100644
> index 000000000000..69a6ddf6ca92
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/iio/adc/adi,ad4134.yaml
> @@ -0,0 +1,198 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/iio/adc/adi,ad4134.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Analog Devices AD4134 ADC
> +
> +maintainers:
> +  - Marcelo Schmitt <marcelo.schmitt@analog.com>
> +
> +description: |
> +  The AD4134 is a quad channel, low noise, simultaneous sampling, precision
> +  analog-to-digital converter (ADC).
> +  Specifications can be found at:
> +    https://www.analog.com/media/en/technical-documentation/data-sheets/ad4134.pdf
> +
> +$ref: /schemas/spi/spi-peripheral-props.yaml#
> +
> +properties:
> +    maxItems: 1
> +
> +  adi,asrc-mode:
> +    $ref: /schemas/types.yaml#/definitions/string
> +    description:
> +      Asynchronous Sample Rate Converter (ASRC) operation mode control input.
> +      Describes whether the MODE pin is set to a high level (for master mode
> +      operation) or to a low level (for slave mode operation).
> +    enum: [ high, low ]
> +    default: low
Since minimim I/O mode is only one currently supported, this should
always be low, right? Is the property needed at this point?

> +
> +  adi,dclkio:
> +    description:
> +      DCLK pin I/O direction control for when the device operates in Pin Control
> +      Slave Mode or in SPI Control Mode. Describes if DEC0/DCLKIO pin is at a
> +      high level (which configures DCLK as an output) or to set to a low level
> +      (configuring DCLK for input).
> +    enum: [ out, in ]
> +    default: in
> +
> +  adi,dclkmode:
> +    description:
> +      DCLK mode control for when the device operates in Pin Control Slave Mode
> +      or in SPI Control Mode. Describes whether the DEC1/DCLKMODE pin is set to
> +      a high level (configuring the DCLK to operate in free running mode) or
> +      to a low level (to configure DCLK to operate in gated mode).
> +    enum: [ free-running, gated ]
> +    default: gated
In minimum I/O mode datasheet mentions this should always be gated.
Perhaps this and adi,dclkio can be left out and added when driver gains
other support than I/O mode?

Thanks,
Tomas


> +
> +required:
> +  - compatible
> +  - reg
> +  - avdd5-supply
> +  - dvdd5-supply
> +  - iovdd-supply
> +  - refin-supply
> +  - clocks
> +  - clock-names
> +
> +allOf:
> +  - if:
> +      not:
> +        required:
> +          - ldoin-supply
> +    then:
> +      required:
> +        - avdd1v8-supply
> +        - dvdd1v8-supply
> +        - clkvdd-supply
> +
> +unevaluatedProperties: false
> +
> +examples:
> +  - |
> +    #include <dt-bindings/gpio/gpio.h>
> +
> +    spi {
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +
> +        adc@0 {
> +            compatible = "adi,ad4134";
> +            reg = <0>;
> +
> +            spi-max-frequency = <1000000>;
> +
> +            reset-gpios = <&gpio0 86 GPIO_ACTIVE_LOW>;
> +            odr-gpios = <&gpio0 87 GPIO_ACTIVE_HIGH>;
> +            powerdown-gpios = <&gpio0 88 GPIO_ACTIVE_LOW>;
> +
> +            clocks = <&sys_clk>;
> +            clock-names = "clkin";
> +
> +            avdd5-supply = <&avdd5>;
> +            dvdd5-supply = <&dvdd5>;
> +            iovdd-supply = <&iovdd>;
> +            refin-supply = <&refin>;
> +            avdd1v8-supply = <&avdd1v8>;
> +            dvdd1v8-supply = <&dvdd1v8>;
> +            clkvdd-supply = <&clkvdd>;
> +
> +            adi,asrc-mode = "low";
> +            adi,dclkio = "in";
> +            adi,dclkmode = "gated";
> +
> +            regulators {
> +                vcm_reg: vcm-output {
> +                    regulator-name = "ad4134-vcm";
> +                };
> +            };
> +
> +        };
> +    };
> +...
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 31d98efb1ad1..b9029c4055e3 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -1449,6 +1449,13 @@ F:	Documentation/ABI/testing/sysfs-bus-iio-adc-ad4130
>  F:	Documentation/devicetree/bindings/iio/adc/adi,ad4130.yaml
>  F:	drivers/iio/adc/ad4130.c
>  
> +ANALOG DEVICES INC AD4134 DRIVER
> +M:	Marcelo Schmitt <marcelo.schmitt@analog.com>
> +L:	linux-iio@vger.kernel.org
> +S:	Supported
> +W:	https://ez.analog.com/linux-software-drivers
> +F:	Documentation/devicetree/bindings/iio/adc/adi,ad4134.yaml
> +
>  ANALOG DEVICES INC AD4170-4 DRIVER
>  M:	Marcelo Schmitt <marcelo.schmitt@analog.com>
>  L:	linux-iio@vger.kernel.org