Re: [PATCH 2/9] dt-bindings: iio: dac: adi-axi-adc: Add ad7606 variant

[Jonathan Cameron <jic23@kernel.org>]

On Thu, 21 Nov 2024 19:53:53 +0000
Conor Dooley <conor@kernel.org> wrote:

> On Thu, Nov 21, 2024 at 10:57:44AM -0600, David Lechner wrote:
> > On 11/21/24 4:18 AM, Guillaume Stols wrote:  
> > > A new compatible is added to reflect the specialized version of the HDL
> > > that is not covered by the IIO backend paradigm: We use the parallel  
> > 
> > It still is being used as an IIO backend, so I would leave out the
> > phrase "that is not covered by the IIO backend paradigm".
> >   
> > > interface to write the ADC's registers, and accessing this interface
> > > requires to use ADI_AXI_REG_CONFIG_RD,ADI_AXI_REG_CONFIG_WR and
> > > ADI_AXI_REG_CONFIG_CTRL in a custom fashion.
> > > 
> > > Signed-off-by: Guillaume Stols <gstols@baylibre.com>
> > > ---
> > >  Documentation/devicetree/bindings/iio/adc/adi,axi-adc.yaml | 7 +++++++
> > >  1 file changed, 7 insertions(+)
> > > 
> > > diff --git a/Documentation/devicetree/bindings/iio/adc/adi,axi-adc.yaml b/Documentation/devicetree/bindings/iio/adc/adi,axi-adc.yaml
> > > index e1f450b80db2..43bc0440c678 100644
> > > --- a/Documentation/devicetree/bindings/iio/adc/adi,axi-adc.yaml
> > > +++ b/Documentation/devicetree/bindings/iio/adc/adi,axi-adc.yaml
> > > @@ -17,13 +17,20 @@ description: |
> > >    interface for the actual ADC, while this IP core will interface
> > >    to the data-lines of the ADC and handle the streaming of data into
> > >    memory via DMA.
> > > +  In some cases, the AXI ADC interface is used to perform specialized
> > > +  operation to a particular ADC, e.g access the physical bus through
> > > +  some special register to write ADC registers.
> > > +  In this case, a different compatible is used, and the driver behaves  
> > 
> > Quick, delete the word "driver" before Krzysztof sees it. :-p  
> 
> And also perhaps worth mentioning under the --- line that the x in the
> compatible is not a wildcard, for similar reasons ;)
Well it is, just one that is used for the IP naming to cover all
the different ADCs it works with.

"The AXI AD7606x IP core can be used to interface the AD7606B, AD7606C-16,
AD7606C-18, AD7605-4, AD7606, AD7606-6, AD7606-4, AD7607, AD7608 and AD7609 devices using an FPGA."

Given that's what ADI calls the IP though we are stuck with it - however
'wrong' they may be :)

But agreed, something to call out to keep me away from the x as well!

Jonathan