Re: [PATCH v4 2/2] dt-bindings: iio: dac: Add docs for AD5770R DAC

[Jonathan Cameron <jic23@kernel.org>]

On Thu, 19 Mar 2020 18:49:22 -0600
Rob Herring <robh@kernel.org> wrote:

> On Tue, Feb 18, 2020 at 02:10:31PM +0200, Alexandru Tachici wrote:
> > Adding dt-bindings documentation for AD5770R DAC.  
> 
> DT list needs to be Cc'ed if you want bindings reviewed.

Doh. I missed that.

> 
> > Signed-off-by: Mircea Caprioru <mircea.caprioru@analog.com>
> > Signed-off-by: Alexandru Tachici <alexandru.tachici@analog.com>
> > ---
> >  .../bindings/iio/dac/adi,ad5770r.yaml         | 185 ++++++++++++++++++
> >  1 file changed, 185 insertions(+)
> >  create mode 100644 Documentation/devicetree/bindings/iio/dac/adi,ad5770r.yaml
> > 
> > diff --git a/Documentation/devicetree/bindings/iio/dac/adi,ad5770r.yaml b/Documentation/devicetree/bindings/iio/dac/adi,ad5770r.yaml
> > new file mode 100644
> > index 000000000000..13d6b5ff479d
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/iio/dac/adi,ad5770r.yaml
> > @@ -0,0 +1,185 @@
> > +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> > +# Copyright 2020 Analog Devices Inc.
> > +%YAML 1.2
> > +---
> > +$id: http://devicetree.org/schemas/bindings/iio/adc/adi,ad5770r.yaml#  
> 
> Jonathan mentioned 'adc' part, but 'bindings' is also wrong. Should be:

Alexandru, please send a fixup patch for the various things Rob has highlighted.

Jonathan


> 
> .../schemas/iio/dac/...
> 
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > +
> > +title: Analog Devices AD5770R DAC device driver
> > +
> > +maintainers:
> > +  - Mircea Caprioru <mircea.caprioru@analog.com>
> > +
> > +description: |
> > +  Bindings for the Analog Devices AD5770R current DAC device. Datasheet can be
> > +  found here:
> > +    https://www.analog.com/media/en/technical-documentation/data-sheets/AD5770R.pdf
> > +
> > +properties:
> > +  compatible:
> > +    enum:
> > +      - adi,ad5770r
> > +
> > +  reg:
> > +    maxItems: 1
> > +
> > +  avdd-supply:
> > +    description:
> > +      AVdd voltage supply. Represents two different supplies in the datasheet
> > +      that are in fact the same.
> > +
> > +  iovdd-supply:
> > +    description:
> > +      Voltage supply for the chip interface.
> > +
> > +  vref-supply:
> > +    description: Specify the voltage of the external reference used.
> > +      Available reference options are 1.25 V or 2.5 V. If no
> > +      external reference declared then the device will use the
> > +      internal reference of 1.25 V.
> > +
> > +  adi,external-resistor:
> > +    description: Specify if an external 2.5k ohm resistor is used. If not
> > +      specified the device will use an internal 2.5k ohm resistor.
> > +      The precision resistor is used for reference current generation.
> > +    type: boolean
> > +
> > +  reset-gpios:
> > +    description: GPIO spec for the RESET pin. If specified, it will be
> > +      asserted during driver probe.
> > +    maxItems: 1
> > +
> > +  channel0:  
> 
> channel@0 ???
> 
> Once you fix that, your example will start failing.
> 
> > +    description: Represents an external channel which are
> > +      connected to the DAC. Channel 0 can act both as a current
> > +      source and sink.
> > +    type: object
> > +
> > +    properties:
> > +      num:  
> 
> Use 'reg' instead.
> 
> > +        description: This represents the channel number.
> > +        items:  
> 
> You can drop items.
> 
> > +          const: 0
> > +
> > +      adi,range-microamp:
> > +          description: Output range of the channel.
> > +          oneOf:
> > +            - $ref: /schemas/types.yaml#/definitions/int32-array  
> 
> *-microamp already has a type, so this should be dropped. However, I 
> believe it's unsigned currently, but we can fix it to be signed.
> 
> > +            - items:
> > +                - enum: [0 300000]
> > +                - enum: [-60000 0]
> > +                - enum: [-60000 300000]  
> 
> Negative values don't yet work until we fix dtc to be able to output 
> negative values. For now, can you just avoid negative numbers in the 
> example.
> 
> What's defined here doesn't match the example. You are saying there are 
> 3 cells with 2 possible values each. I think you want:
> 
> oneOf:
>   - items:
>       - const: 0
>       - const: 300000
>   - items:
>       - const: -60000
>       - const: 0
>   - items:
>       - const: -60000
>       - const: 300000
>       
> 
> > +
> > +  channel1:
> > +    description: Represents an external channel which are
> > +      connected to the DAC.
> > +    type: object
> > +
> > +    properties:
> > +      num:
> > +        description: This represents the channel number.
> > +        items:
> > +          const: 1
> > +
> > +      adi,range-microamp:
> > +          description: Output range of the channel.
> > +          oneOf:
> > +            - $ref: /schemas/types.yaml#/definitions/uint32-array
> > +            - items:
> > +                - enum: [0 140000]
> > +                - enum: [0 250000]
> > +
> > +  channel2:
> > +    description: Represents an external channel which are
> > +      connected to the DAC.
> > +    type: object
> > +
> > +    properties:
> > +      num:
> > +        description: This represents the channel number.
> > +        items:
> > +          const: 2
> > +
> > +      adi,range-microamp:
> > +          description: Output range of the channel.
> > +          oneOf:
> > +            - $ref: /schemas/types.yaml#/definitions/uint32-array
> > +            - items:
> > +                - enum: [0 140000]
> > +                - enum: [0 250000]
> > +
> > +patternProperties:
> > +  "^channel@([3-5])$":
> > +    type: object
> > +    description: Represents the external channels which are connected to the DAC.
> > +    properties:
> > +      num:
> > +        description: This represents the channel number.
> > +        items:
> > +          minimum: 3
> > +          maximum: 5
> > +
> > +      adi,range-microamp:
> > +          description: Output range of the channel.
> > +          oneOf:
> > +            - $ref: /schemas/types.yaml#/definitions/uint32-array
> > +            - items:
> > +                - enum: [0 45000]
> > +                - enum: [0 100000]
> > +
> > +required:
> > +- reg
> > +- diff-channels
> > +- channel0
> > +- channel1
> > +- channel2
> > +- channel3
> > +- channel4
> > +- channel5
> > +
> > +examples:
> > +  - |
> > +        spi {
> > +                #address-cells = <1>;
> > +                #size-cells = <0>;
> > +
> > +                ad5770r@0 {
> > +                        compatible = "ad5770r";
> > +                        reg = <0>;
> > +                        spi-max-frequency = <1000000>;
> > +                        vref-supply = <&vref>;
> > +                        adi,external-resistor;
> > +                        reset-gpios = <&gpio 22 0>;
> > +
> > +                        channel@0 {
> > +                                num = <0>;
> > +                                adi,range-microamp = <(-60000) 300000>;
> > +                        };
> > +
> > +                        channel@1 {
> > +                                num = <1>;
> > +                                adi,range-microamp = <0 140000>;
> > +                        };
> > +
> > +                        channel@2 {
> > +                                num = <2>;
> > +                                adi,range-microamp = <0 55000>;
> > +                        };
> > +
> > +                        channel@3 {
> > +                                num = <3>;
> > +                                adi,range-microamp = <0 45000>;
> > +                        };
> > +
> > +                        channel@4 {
> > +                                num = <4>;
> > +                                adi,range-microamp = <0 45000>;
> > +                        };
> > +
> > +                        channel@5 {
> > +                                num = <5>;
> > +                                adi,range-microamp = <0 45000>;
> > +                        };
> > +                };
> > +        };
> > +...
> > -- 
> > 2.20.1
> >