Re: [PATCH v2 1/4] dt-bindings: iio: adc: ad7768-1: add new supported parts

[Jonathan Santos <jonath4nns@gmail.com>]

On 08/24, Krzysztof Kozlowski wrote:
> On 24/08/2025 06:09, Jonathan Santos wrote:
> > Add compatibles for supported parts in the ad7768-1 family:
> > 	ADAQ7767-1, ADAQ7768-1 and ADAQ7769-1
> > 
> > Add property and checks for AAF gain, supported by ADAQ7767-1
> > and ADAQ7769-1 parts:
> > 	adi,gain-milli
> > 
> > Signed-off-by: Jonathan Santos <Jonathan.Santos@analog.com>
> 
> git send-email v2*
> 
> Not patch by patch. You made it very difficult for us to review and to
> apply.
> 

Sorry, i will pay more attention

> > ---
> > v2 Changes:
> > * adi,aaf-gain property renamed to adi,gain-milli. Description was 
> >   simplified.
> > * default value add to adi,gain-milli.
> > ---
> >  .../bindings/iio/adc/adi,ad7768-1.yaml        | 43 +++++++++++++++++--
> >  1 file changed, 39 insertions(+), 4 deletions(-)
> > 
> > diff --git a/Documentation/devicetree/bindings/iio/adc/adi,ad7768-1.yaml b/Documentation/devicetree/bindings/iio/adc/adi,ad7768-1.yaml
> > index c06d0fc791d3..0c39491f6179 100644
> > --- a/Documentation/devicetree/bindings/iio/adc/adi,ad7768-1.yaml
> > +++ b/Documentation/devicetree/bindings/iio/adc/adi,ad7768-1.yaml
> > @@ -4,18 +4,26 @@
> >  $id: http://devicetree.org/schemas/iio/adc/adi,ad7768-1.yaml#
> >  $schema: http://devicetree.org/meta-schemas/core.yaml#
> >  
> > -title: Analog Devices AD7768-1 ADC device driver
> > +title: Analog Devices AD7768-1 ADC family
> >  
> >  maintainers:
> >    - Michael Hennerich <michael.hennerich@analog.com>
> >  
> >  description: |
> > -  Datasheet at:
> > -    https://www.analog.com/media/en/technical-documentation/data-sheets/ad7768-1.pdf
> > +  Analog Devices AD7768-1 24-Bit Single Channel Low Power sigma-delta ADC family
> > +
> > +  https://www.analog.com/media/en/technical-documentation/data-sheets/ad7768-1.pdf
> > +  https://www.analog.com/media/en/technical-documentation/data-sheets/adaq7767-1.pdf
> > +  https://www.analog.com/media/en/technical-documentation/data-sheets/adaq7768-1.pdf
> > +  https://www.analog.com/media/en/technical-documentation/data-sheets/adaq7769-1.pdf
> >  
> >  properties:
> >    compatible:
> > -    const: adi,ad7768-1
> > +    enum:
> > +      - adi,ad7768-1
> > +      - adi,adaq7767-1
> > +      - adi,adaq7768-1
> > +      - adi,adaq7769-1
> >  
> >    reg:
> >      maxItems: 1
> > @@ -58,6 +66,18 @@ properties:
> >      description:
> >        ADC reference voltage supply
> >  
> > +  adi,gain-milli:
> > +    description: |
> > +       Specifies the gain applied by the Analog Anti-Aliasing Filter (AAF) to the
> > +       ADC input (in milli units). The hardware gain is determined by which input
> 
> 
> I don't think there is no such thing as "milli units". milli is SI
> prefix, not unit. So "units" is the unit? Or how exactly?
> 
> Basis points were before since 2022 so I don't get why these other
> bindings introduced in 2024 could not use it?
> 
> Anyway, if you ever do not apply reviewers comment, then your commit msg
> should explain this. Otherwise you get the same discussion here.
> 

Yes, you are right. We shouldn't use milli as suffix. However, may I
suggest another option?

I believe -permille is more appropriate because it represents a 1/1000
proportion, which gives the precision we need to cover all values.

so it would be something like: adi,aaf-gain-permille

Is that ok for you?

Thanks for the feedback,
Jonathan S.

> Best regards,
> Krzysztof