Re: [PATCH 1/2] dt-bindings: adc: add AD717X

From: Rob Herring
Date: Thu Aug 10 2023 - 16:51:15 EST


On Thu, Aug 10, 2023 at 12:33:16PM +0300, Dumitru Ceclan wrote:
> The AD717x family offer a complete integrated Sigma-Delta ADC solution
> which can be used in high precision, low noise single channel
> applications or higher speed multiplexed applications. The Sigma-Delta
> ADC is intended primarily for measurement of signals close to DC but also
> delivers outstanding performance with input bandwidths out to ~10kHz.
>
> Signed-off-by: Dumitru Ceclan <mitrutzceclan@xxxxxxxxx>
> ---
> .../bindings/iio/adc/adi,ad717x.yaml | 158 ++++++++++++++++++
> 1 file changed, 158 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/iio/adc/adi,ad717x.yaml
>
> diff --git a/Documentation/devicetree/bindings/iio/adc/adi,ad717x.yaml b/Documentation/devicetree/bindings/iio/adc/adi,ad717x.yaml
> new file mode 100644
> index 000000000000..f12926e69958
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/iio/adc/adi,ad717x.yaml
> @@ -0,0 +1,158 @@
> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> +# Copyright 2023 Analog Devices Inc.
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/iio/adc/adi,ad717x.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Analog Devices AD717X ADC family SPI driver

Drop 'SPI driver'. This is not a driver.

> +
> +maintainers:
> + - Ceclan Dumitru <dumitru.ceclan@xxxxxxxxxx>
> +
> +description: |
> + Bindings for the Analog Devices AD717X ADC's. Datasheets for supported chips:
> + https://www.analog.com/media/en/technical-documentation/data-sheets/AD7172-2.pdf
> + https://www.analog.com/media/en/technical-documentation/data-sheets/AD7173-8.pdf
> + https://www.analog.com/media/en/technical-documentation/data-sheets/AD7175-2.pdf
> + https://www.analog.com/media/en/technical-documentation/data-sheets/AD7176-2.pdf
> +
> +properties:
> + compatible:
> + enum:
> + - adi,ad7172-2
> + - adi,ad7173-8
> + - adi,ad7175-2
> + - adi,ad7176-2
> +
> + reg:
> + maxItems: 1
> +
> + interrupts:
> + maxItems: 1
> +
> + '#address-cells':
> + const: 1
> +
> + '#size-cells':
> + const: 0
> +
> + spi-max-frequency:
> + maximum: 20000000
> +
> + spi-cpol:
> + type: boolean
> +
> + spi-cpha:
> + type: boolean
> +
> + adi,temp-channel:
> + description:
> + Enables temperature reading channel
> + type: boolean
> +
> + dependencies:
> + adi,temp-channel:
> + compatible:
> + enum:
> + - adi,ad7172-2
> + - adi,ad7173-8
> + - adi,ad7175-2

That's not actually valid schema. You are missing "properties" above
"compatible". I'm also not sure the tools which do a number of
fixups/transforms on schemas would handle this. I do think this is a bit
nicer than the if/then schemas we normally use for restricting
properties by compatibles.

> +
> +

Extra blank line.

> + required:
> + - compatible
> + - reg
> + - interrupts
> + - spi-cpol
> + - spi-cpha

If the device(s) are not configurable, then you shouldn't need these 2
properties. The driver can hardcode the correct setting.

> +
> +patternProperties:
> + "^channel@([0-9a-f])$":

Don't need ().

> + type: object
> + $ref: adc.yaml
> + unevaluatedProperties: false
> +
> + properties:
> + reg:
> + description: Channel number
> + minimum: 0
> + maximum: 15
> +
> + diff-channels:
> + description:
> + Analog input pins
> + items:
> + minimum: 0
> + maximum: 31
> +
> + adi,bipolar:
> + description: Specify if the channel should measure in bipolar mode.
> + type: boolean
> +
> + required:
> + - reg
> + - diff-channels
> +
> +allOf:
> + - $ref: /schemas/spi/spi-peripheral-props.yaml#
> +
> +unevaluatedProperties: false
> +
> +examples:
> + - |
> + #include <dt-bindings/gpio/gpio.h>
> + #include <dt-bindings/interrupt-controller/irq.h>
> +
> + spi {
> + status = "okay";

Drop status.

You need #address-cells and #size-cells. Did you test this?

> +
> + ad7173@0 {
> + compatible = "adi,ad7173-8";
> + reg = <0>;
> +
> + #address-cells = <1>;
> + #size-cells = <0>;
> +
> + interrupts = <25 IRQ_TYPE_EDGE_FALLING>;
> + interrupt-parent = <&gpio>;
> + spi-max-frequency = <5000000>;
> + spi-cpol;
> + spi-cpha;
> +
> + adi,temp-channel;
> +
> + channel@0 {
> + reg = <0>;
> + adi,bipolar;
> +
> + diff-channels = <0 1>;
> + };
> +
> + channel@1 {
> + reg = <1>;
> +
> + diff-channels = <2 3>;
> + };
> +
> + channel@2 {
> + reg = <2>;
> + adi,bipolar;
> +
> + diff-channels = <4 5>;
> + };
> +
> + channel@3 {
> + reg = <3>;
> + adi,bipolar;
> +
> + diff-channels = <6 7>;
> + };
> +
> + channel@4 {
> + reg = <4>;
> +
> + diff-channels = <8 9>;
> + };
> + };
> + };
> --
> 2.30.2
>