Re: [PATCH] dt-bindings: iio: adc: Migrate MCP3911 documentation to yaml

[Marcus Folkesson]

Hi Rob,

Thank you for comment. See inline comments.

I will apply the changes to this pending patch as well.
Subject: [PATCH] dt-bindings: iio: dac: Migrate LTC1660 documentation to yaml

On Tue, Nov 05, 2019 at 09:49:20PM -0600, Rob Herring wrote:
> On Tue, Oct 29, 2019 at 10:11:42PM +0100, Marcus Folkesson wrote:
> > Rewrite bindings to use json-schema vocabulary.
> > 
> > Signed-off-by: Marcus Folkesson <marcus.folkesson@xxxxxxxxx>
> > ---
> >  .../devicetree/bindings/iio/adc/mcp3911.txt   | 30 --------
> >  .../bindings/iio/adc/microchip,mcp3911.yaml   | 72 +++++++++++++++++++
> >  MAINTAINERS                                   |  2 +-
> >  3 files changed, 73 insertions(+), 31 deletions(-)
> >  delete mode 100644 Documentation/devicetree/bindings/iio/adc/mcp3911.txt
> >  create mode 100644 Documentation/devicetree/bindings/iio/adc/microchip,mcp3911.yaml
> > 
> > diff --git a/Documentation/devicetree/bindings/iio/adc/mcp3911.txt b/Documentation/devicetree/bindings/iio/adc/mcp3911.txt
> > deleted file mode 100644
> > index 3071f48fb30b..000000000000
> > --- a/Documentation/devicetree/bindings/iio/adc/mcp3911.txt
> > +++ /dev/null
> > @@ -1,30 +0,0 @@
> > -* Microchip MCP3911 Dual channel analog front end (ADC)
> > -
> > -Required properties:
> > - - compatible: Should be "microchip,mcp3911"
> > - - reg: SPI chip select number for the device
> > -
> > -Recommended properties:
> > - - spi-max-frequency: Definition as per
> > -	 Documentation/devicetree/bindings/spi/spi-bus.txt.
> > -	 Max frequency for this chip is 20MHz.
> > -
> > -Optional properties:
> > - - clocks: Phandle and clock identifier for sampling clock
> > - - interrupt-parent: Phandle to the parent interrupt controller
> > - - interrupts: IRQ line for the ADC
> > - - microchip,device-addr: Device address when multiple MCP3911 chips are present on the
> > -	same SPI bus. Valid values are 0-3. Defaults to 0.
> > - - vref-supply: Phandle to the external reference voltage supply.
> > -
> > -Example:
> > -adc@0 {
> > -	compatible = "microchip,mcp3911";
> > -	reg = <0>;
> > -	interrupt-parent = <&gpio5>;
> > -	interrupts = <15 IRQ_TYPE_EDGE_RISING>;
> > -	spi-max-frequency = <20000000>;
> > -	microchip,device-addr = <0>;
> > -	vref-supply = <&vref_reg>;
> > -	clocks = <&xtal>;
> > -};
> > diff --git a/Documentation/devicetree/bindings/iio/adc/microchip,mcp3911.yaml b/Documentation/devicetree/bindings/iio/adc/microchip,mcp3911.yaml
> > new file mode 100644
> > index 000000000000..bfcf6a5fb44e
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/iio/adc/microchip,mcp3911.yaml
> > @@ -0,0 +1,72 @@
> > +# SPDX-License-Identifier: GPL-2.0
> > +# Copyright 2019 Marcus Folkesson <marcus.folkesson@xxxxxxxxx>
> > +%YAML 1.2
> > +---
> > +$id: "http://devicetree.org/schemas/bindings/iio/adc/microchip,mcp3911.yaml#";
> > +$schema: "http://devicetree.org/meta-schemas/core.yaml#";
> > +
> > +title: Microchip MCP3911 Dual channel analog front end (ADC)
> > +
> > +maintainers:
> > +  - Marcus Folkesson <marcus.folkesson@xxxxxxxxx>
> > +  - Kent Gustavsson <nedo80@xxxxxxxxx>
> > +
> > +description: |
> > +  Bindings for the Microchip MCP3911 Dual channel ADC device. Datasheet can be
> > +  found here: https://ww1.microchip.com/downloads/en/DeviceDoc/20002286C.pdf
> > +
> > +properties:
> > +  compatible:
> > +    enum:
> > +      - microchip,mcp3911
> > +
> > +  reg:
> > +    description: SPI chip select number for the device
> 
> No need to describe common properties if you have nothing special for 
> this device to say.
> 

OK

> > +    maxItems: 1
> > +
> > +  spi-max-frequency:
> > +    description: |
> > +      Definition as per Documentation/devicetree/bindings/spi/spi-bus.txt.
> 
> Same here.
> 
> > +    maximum: 20000000
> > +    maxItems: 1

Should I keep the maximum property?

> 
> Not an array, so drop.
> 
> > +
> > +  clocks:
> > +    description: Phandle and clock identifier for sampling clock
> 
> Same comment on descriptions.
> 

I describe it a little bit more. Thanks

> > +    maxItems: 1
> > +
> > +  interrupts:
> > +    description: IRQ line of the ADC
> > +    maxItems: 1
> > +
> > +  microchip,device-addr:
> > +    description: Device address when multiple MCP3911 chips are present on the same SPI bus.
> > +    allOf:
> > +      - $ref: /schemas/types.yaml#/definitions/uint32
> > +      - enum: [0, 1, 2, 3]
> > +      - default: 0
> > +
> > +  vref-supply:
> > +    description: Phandle to the external reference voltage supply.
> > +    maxItems: 1
> 
> Drop this *-supply is always 1 item.
> 

OK

> > +
> > +required:
> > +  - compatible
> > +  - reg
> > +
> > +examples:
> > +  - |
> > +    spi {
> > +      #address-cells = <1>;
> > +      #size-cells = <0>;
> > +
> > +      adc@0 {
> > +        compatible = "microchip,mcp3911";
> > +        reg = <0>;
> > +        interrupt-parent = <&gpio5>;
> > +        interrupts = <15 2>;
> > +        spi-max-frequency = <20000000>;
> > +        microchip,device-addr = <0>;
> > +        vref-supply = <&vref_reg>;
> > +        clocks = <&xtal>;
> > +      };
> > +    };
> > diff --git a/MAINTAINERS b/MAINTAINERS
> > index e51a68bf8ca8..fbccc9d450ff 100644
> > --- a/MAINTAINERS
> > +++ b/MAINTAINERS
> > @@ -10723,7 +10723,7 @@ M:	Kent Gustavsson <kent@xxxxxxxxxx>
> >  L:	linux-iio@xxxxxxxxxxxxxxx
> >  S:	Supported
> >  F:	drivers/iio/adc/mcp3911.c
> > -F:	Documentation/devicetree/bindings/iio/adc/mcp3911.txt
> > +F:	Documentation/devicetree/bindings/iio/adc/microchip,mcp3911.yaml
> >  
> >  MICROCHIP NAND DRIVER
> >  M:	Tudor Ambarus <tudor.ambarus@xxxxxxxxxxxxx>
> > -- 
> > 2.23.0
> > 

Thanks,
Marcus Folkesson