Re: [PATCH 4/4] iio: adc: ti-ads112c14: add measurement channel support

[David Lechner]

On 6/15/26 5:00 PM, David Lechner (TI) wrote:
> Add support for parsing devicetree properties for measurement channels
> and doing direct reads on these.
> 
> There are quite a lot of conditions that have to be met for each
> measurement to be made, so quite a bit of state and algorithms are
> required to handle it.
> 
> Channels are created dynamically since the number of possibilities is
> unreasonably large.
> 

...

>  static void ads112c14_populate_tables(struct ads112c14_data *data)
>  {
>  	u32 vref_uV, fsr_bits;
> -	int i;
> +
> +	for (u32 i = 0; i < data->num_measurements; i++) {
> +		struct ads112c14_measurement *measurement = &data->measurements[i];
> +
> +		switch (measurement->vref_source) {
> +		case ADS112C14_VREF_SOURCE_EXTERNAL:
> +			if (data->ext_ref_ohms)
> +				vref_uV = measurement->idac_current_uA *
> +					  measurement->iadc_count * data->ext_ref_ohms;

One thing I am considering is that if we have a resistor between
REFP and REFN rather than a voltage supply, then we should consider
the channel IIO_RESISTANCE rather than IIO_VOLTAGE.

In this case, the user doesn't care about voltage at all, but rather
the ratio of the REFP-REFN resistor to the measured resistance.