Re: [PATCH v4 1/2] staging: iio: ad7780: update voltage on read

["Ardelean, Alexandru" <alexandru.Ardelean@analog.com>]

On Mon, 2018-11-05 at 17:14 -0200, Renato Lui Geh wrote:
> The ad7780 driver previously did not read the correct device output, as
> it read an outdated value set at initialization. It now updates its
> voltage on read.
> 

Looks good from my side.

Alex

> Signed-off-by: Renato Lui Geh <renatogeh@gmail.com>
> ---
> Changes in v3:
> 	- removed initialization (int voltage_uv = 0)
> 	- returns error when voltage_uv is null
> Changes in v4:
> 	- returns error when voltage_uv is negative
> 
>  drivers/staging/iio/adc/ad7780.c | 6 +++++-
>  1 file changed, 5 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/staging/iio/adc/ad7780.c
> b/drivers/staging/iio/adc/ad7780.c
> index b67412db0318..c7cb05cedbbc 100644
> --- a/drivers/staging/iio/adc/ad7780.c
> +++ b/drivers/staging/iio/adc/ad7780.c
> @@ -87,12 +87,16 @@ static int ad7780_read_raw(struct iio_dev *indio_dev,
>  			   long m)
>  {
>  	struct ad7780_state *st = iio_priv(indio_dev);
> +	int voltage_uv;
>  
>  	switch (m) {
>  	case IIO_CHAN_INFO_RAW:
>  		return ad_sigma_delta_single_conversion(indio_dev, chan,
> val);
>  	case IIO_CHAN_INFO_SCALE:
> -		*val = st->int_vref_mv * st->gain;
> +		voltage_uv = regulator_get_voltage(st->reg);
> +		if (voltage_uv < 0)
> +			return voltage_uv;
> +		*val = (voltage_uv / 1000) * st->gain;
>  		*val2 = chan->scan_type.realbits - 1;
>  		return IIO_VAL_FRACTIONAL_LOG2;
>  	case IIO_CHAN_INFO_OFFSET: