Re: [PATCH v6 2/2] iio: adc: ad7173: add AD7173 driver

[Jonathan Cameron <jic23@xxxxxxxxxx>]

On Mon, 4 Dec 2023 18:49:21 +0200
Ceclan Dumitru <mitrutzceclan@xxxxxxxxx> wrote:

> On 11/25/23 19:21, Jonathan Cameron wrote:
> > On Thu, 23 Nov 2023 17:23:22 +0200
> > mitrutzceclan <mitrutzceclan@xxxxxxxxx> wrote:
> >   
> >> From: Dumitru Ceclan <mitrutzceclan@xxxxxxxxx>  
> 
> ...
> >> +	st->regulators[0].supply = ad7173_ref_sel_str[AD7173_SETUP_REF_SEL_EXT_REF];
> >> +	st->regulators[1].supply = ad7173_ref_sel_str[AD7173_SETUP_REF_SEL_EXT_REF2];
> >> +	st->regulators[2].supply = ad7173_ref_sel_str[AD7173_SETUP_REF_SEL_AVDD1_AVSS];
> >> +
> >> +	ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(st->regulators),
> >> +				      st->regulators);  
> > 
> > If only some of them are supplied, the driver works fine as long as no channel is using them?
> > If so should probably get the optionally then check for availability of the ones you
> > want.  I'm sure someone will just wire up ref.  Incidentally, ref2 isn't there for all chips
> > I think, so we should not get it on the ones where it can't exist.
> >   
> 
> 
> This sets a dummy regulator in place if no proper supply is found. Then
> the call regulator_get_voltage() on the dummy will fail. About getting
> ref2, sure, I'll set the string only with the right ID.
> 
> ...
> >> +		ret = ad7173_get_ref_voltage_milli(st, (u8)ref_sel);
> >> +		if (ret < 0)
> >> +			return dev_err_probe(dev, ret,
> >> +					     "Cannot use reference %u", ref_sel);  
> 
> Here the probe would not continue if a channel selects a supply that is
> not available in the DT.
Ok. It's a little ugly though - so maybe a comment at the bulk_get to say
it will fail cleanly a bit later.