Re: [PATCH] dt-bindings: iio: adc: add adi,ad7780.yaml binding

From: Jonathan Cameron
Date: Sun May 19 2019 - 13:00:11 EST


On Sat, 18 May 2019 19:41:12 -0300
Renato Lui Geh <renatogeh@xxxxxxxxx> wrote:

> This patch adds a YAML binding for the Analog Devices AD7780/1 and
> AD7170/1 analog-to-digital converters.
>
> Signed-off-by: Renato Lui Geh <renatogeh@xxxxxxxxx>
One comment inline. I'll also be needing an ack from Analog on this,
preferably Michael's.

Thanks,

Jonathan
> ---
> .../bindings/iio/adc/adi,ad7780.txt | 48 -----------
> .../bindings/iio/adc/adi,ad7780.yaml | 85 +++++++++++++++++++
> 2 files changed, 85 insertions(+), 48 deletions(-)
> delete mode 100644 Documentation/devicetree/bindings/iio/adc/adi,ad7780.txt
> create mode 100644 Documentation/devicetree/bindings/iio/adc/adi,ad7780.yaml
>
> diff --git a/Documentation/devicetree/bindings/iio/adc/adi,ad7780.txt b/Documentation/devicetree/bindings/iio/adc/adi,ad7780.txt
> deleted file mode 100644
> index 440e52555349..000000000000
> --- a/Documentation/devicetree/bindings/iio/adc/adi,ad7780.txt
> +++ /dev/null
> @@ -1,48 +0,0 @@
> -* Analog Devices AD7170/AD7171/AD7780/AD7781
> -
> -Data sheets:
> -
> -- AD7170:
> - * https://www.analog.com/media/en/technical-documentation/data-sheets/AD7170.pdf
> -- AD7171:
> - * https://www.analog.com/media/en/technical-documentation/data-sheets/AD7171.pdf
> -- AD7780:
> - * https://www.analog.com/media/en/technical-documentation/data-sheets/ad7780.pdf
> -- AD7781:
> - * https://www.analog.com/media/en/technical-documentation/data-sheets/AD7781.pdf
> -
> -Required properties:
> -
> -- compatible: should be one of
> - * "adi,ad7170"
> - * "adi,ad7171"
> - * "adi,ad7780"
> - * "adi,ad7781"
> -- reg: spi chip select number for the device
> -- vref-supply: the regulator supply for the ADC reference voltage
> -
> -Optional properties:
> -
> -- powerdown-gpios: must be the device tree identifier of the PDRST pin. If
> - specified, it will be asserted during driver probe. As the
> - line is active high, it should be marked GPIO_ACTIVE_HIGH.
> -- adi,gain-gpios: must be the device tree identifier of the GAIN pin. Only for
> - the ad778x chips. If specified, it will be asserted during
> - driver probe. As the line is active low, it should be marked
> - GPIO_ACTIVE_LOW.
> -- adi,filter-gpios: must be the device tree identifier of the FILTER pin. Only
> - for the ad778x chips. If specified, it will be asserted
> - during driver probe. As the line is active low, it should be
> - marked GPIO_ACTIVE_LOW.
> -
> -Example:
> -
> -adc@0 {
> - compatible = "adi,ad7780";
> - reg = <0>;
> - vref-supply = <&vdd_supply>
> -
> - powerdown-gpios = <&gpio 12 GPIO_ACTIVE_HIGH>;
> - adi,gain-gpios = <&gpio 5 GPIO_ACTIVE_LOW>;
> - adi,filter-gpios = <&gpio 15 GPIO_ACTIVE_LOW>;
> -};
> diff --git a/Documentation/devicetree/bindings/iio/adc/adi,ad7780.yaml b/Documentation/devicetree/bindings/iio/adc/adi,ad7780.yaml
> new file mode 100644
> index 000000000000..931bc4f8ec04
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/iio/adc/adi,ad7780.yaml
> @@ -0,0 +1,85 @@
> +# SPDX-License-Identifier: GPL-2.0
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/iio/adc/adi,ad7780.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Analog Devices AD7170/AD7171/AD7780/AD7781 analog to digital converters
> +
> +maintainers:
> + - Michael Hennerich <michael.hennerich@xxxxxxxxxx>
> +
> +description: |
> + The ad7780 is a sigma-delta analog to digital converter. This driver provides
> + reading voltage values and status bits from both the ad778x and ad717x series.
> + Its interface also allows writing on the FILTER and GAIN GPIO pins on the
> + ad778x.
> +
> + Specifications on the converters can be found at:
> + AD7170:
> + https://www.analog.com/media/en/technical-documentation/data-sheets/AD7170.pdf
> + AD7171:
> + https://www.analog.com/media/en/technical-documentation/data-sheets/AD7171.pdf
> + AD7780:
> + https://www.analog.com/media/en/technical-documentation/data-sheets/ad7780.pdf
> + AD7781:
> + https://www.analog.com/media/en/technical-documentation/data-sheets/AD7781.pdf
> +
> +properties:
> + compatible:
> + enum:
> + - adi,ad7170
> + - adi,ad7171
> + - adi,ad7780
> + - adi,ad7781
> +
> + reg:
> + description:
> + Chip select number for the device
> + maxItems: 1
> +
> + vref-supply:
> + description:
> + The regulator supply for the ADC reference voltage
> + maxItems: 1
> +
> + powerdown-gpios:
> + description:
> + Must be the device tree identifier of the PDRST pin. If
> + specified, it will be asserted during driver probe. As the
> + line is active high, it should be marked GPIO_ACTIVE_HIGH.
> + maxItems: 1
> +
> + adi,gain-gpios:
> + description:
> + Must be the device tree identifier of the GAIN pin. Only for
> + the ad778x chips. If specified, it will be asserted during
> + driver probe. As the line is active low, it should be marked
> + GPIO_ACTIVE_LOW.
> + maxItems: 1
> +
> + adi,filter-gpios:
> + description:
> + Must be the device tree identifier of the FILTER pin. Only
> + for the ad778x chips. If specified, it will be asserted
> + during driver probe. As the line is active low, it should be
> + marked GPIO_ACTIVE_LOW.
> + maxItems: 1
> +
> +required:
> + - compatible
> + - reg
> + - vref-supply
Is that actually true? I'd imagine it'll use a stub regulator if
it isn't supplied.

> +
> +examples:
> + - |
> + #include <dt-bindings/gpio/gpio.h>
> + adc@0 {
> + compatible = "adi,ad7780";
> + reg = <0>;
> + vref-supply = <&vdd_supply>;
> +
> + powerdown-gpios = <&gpio0 12 GPIO_ACTIVE_HIGH>;
> + adi,gain-gpios = <&gpio1 5 GPIO_ACTIVE_LOW>;
> + adi,filter-gpios = <&gpio2 15 GPIO_ACTIVE_LOW>;
> + };