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

[Ceclan Dumitru <mitrutzceclan@gmail.com>]

On 11/25/23 19:21, Jonathan Cameron wrote:
> On Thu, 23 Nov 2023 17:23:22 +0200
> mitrutzceclan <mitrutzceclan@gmail.com> wrote:
> 
>> From: Dumitru Ceclan <mitrutzceclan@gmail.com>

...
>> +	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.