Re: [PATCH v2 1/3] dt-bindings: iio: dac: Add AD5529R

[Janani Sunil]

On 5/8/26 15:08, Jonathan Cameron wrote:
> On Fri, 8 May 2026 13:48:43 +0100
> Jonathan Cameron <jic23@xxxxxxxxxx> wrote:
>
> > On Fri, 8 May 2026 13:55:47 +0200
> > Janani Sunil <janani.sunil@xxxxxxxxxx> wrote:
> >
> > > Devicetree bindings for AD5529R 16 channel 12/16 bit high voltage,
> > > buffered voltage output digital-to-analog converter (DAC) with an
> > > integrated precision reference.
> > >
> > > Signed-off-by: Janani Sunil <janani.sunil@xxxxxxxxxx>
> > > ---
> > >   .../devicetree/bindings/iio/dac/adi,ad5529r.yaml   | 96 ++++++++++++++++++++++
> > >   MAINTAINERS                                        |  7 ++
> > >   2 files changed, 103 insertions(+)
> > >
> > > diff --git a/Documentation/devicetree/bindings/iio/dac/adi,ad5529r.yaml b/Documentation/devicetree/bindings/iio/dac/adi,ad5529r.yaml
> > > new file mode 100644
> > > index 000000000000..f531b4865b01
> > > --- /dev/null
> > > +++ b/Documentation/devicetree/bindings/iio/dac/adi,ad5529r.yaml
> > > @@ -0,0 +1,96 @@
> > > +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> > > +%YAML 1.2
> > > +---
> > > +$id: http://devicetree.org/schemas/iio/dac/adi,ad5529r.yaml#
> > > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > > +
> > > +title: Analog Devices AD5529R 16-Channel 12/16-bit High Voltage DAC
> > How is one device bother 12 and 16-bit? That sometimes happens for
> > ADCs where it is really reflecting oversampling or for device with hardware
> > FIFOs where storage space is saved by using lower bit rate. I'm not sure either
> > applies here.
> Having read the driver I now understand. This is supporting two parts and
> doing device ID based detection.  In an unusual step for Analog they have
> the same base part number with a post fix.  Whilst this approach works today
> it fundamentally breaks fallback dt-compatibles being used in future (the
> driver fails for any non match of WHOAMI value as it needs them to look
> up device specific data)  As such I think you need to have separate
> compatibles for the 12 and 16 bit versions.

AD5529R supports two variants- AD5529R-12 bit and AD5529R-16 bit. They share the same register interface and pin configuration
but differ in DAC resolution. I will add separate compatibles for this case.

Best Regards,
Janani Sunil