RE: [PATCH v3 1/4] dt-bindings: iio: adc: add bindings for AD4691 family

[Sabau, Radu bogdan]

> -----Original Message-----
> From: David Lechner <dlechner@xxxxxxxxxxxx>
> Sent: Monday, March 16, 2026 5:14 PM

...

> > I agree with this, since only DATA_READY will be used anyway as an interrupt
> > in CNV_CLOCK mode.
> > In fact, I am now thinking of removing ADC_BUSY entirely, since its used in
> > just two cases, which none of them perhaps make sense :
> >
> > 1. Manual Mode,where ADC_BUSY is selected for GPx, though is not used as
> > an interrupt or 'feedback' of anyway.
> > 2. Autonomous Mode, where in theory it would be used to see when each
> > channel was sampled, but this mode is used for just once channel single
> > shot reading, so again, not actually used.
> >
> > The implementation would see the enum removed and just initializing
> > the GPx pin used as DATA READY using a macro.
> >
> > What are your thoughts on this?
> 
> 
> We should try to consider every reasonable possible wiring situation.
> The only case I can think where the devicetree might need to know the
> requested function in addition to which pin is if the pin is wired to
> something not controlled by Linux. That is an odd enough situation though
> that we could defer considering that. I think we could add support for such
> a thing later if we needed to without breaking the existing bindings.
> 
> So hopefully I am thinking clearly enough about this to say, yes, we
> should just go with #trigger-source-cells = <1>; where the cell is the
> GP pin number.
> 

I agree. This will be covered in the next version then.

> >
> >>
> >>> +        - Second cell: GPIO pin number (only 0 = GP0 is supported)

...

> >
> > In this example, I would say this is needed since the CNV PWM is
> > not only starting the conversion on the ADC, but also controlling
> > the sampling rate, making custom sampling rates available in
> > comparison to the internal oscillator used by AUTONOMOUS.
> 
> The point was to have an example that shows SPI offload usage.
> I assume this would be more common that PWM without SPI offload.
> 

Indeed, this mode would be more commonly used with offload. However
the PWM would also be used although offload is not.

> >
> >>> +
> >>> +            interrupts = <12 4>;
> >
> > Best Regards,
> > Radu