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

[Ardelean, Alexandru]

On Sun, 2018-11-11 at 14:30 +0000, Jonathan Cameron wrote:
> On Tue, 6 Nov 2018 09:24:44 +0000
> "Ardelean, Alexandru" <alexandru.Ardelean@xxxxxxxxxx> wrote:
> 
> > 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 it read an outdated value set at initialization.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.
> > >   
> 
> Applied to the togreg branch of iio.git and pushed out as testing for
> the autobuilders to check it.  I'm not that fussed about pushing this
> one as a fix, as most of the time these things are on fixed regulators
> anyway, but it is nice to do it right.
> 
> > Looks good from my side.
> 
> Ack?

Acked-by: Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx>

> 
> Much preferred if you are willing to give a formal acknowledgement.
> 
> Thanks,
> 
> Jonathan
> 
> 
> > 
> > Alex
> > 
> > > Signed-off-by: Renato Lui Geh <renatogeh@xxxxxxxxx>
> > > ---
> > > 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:  
> 
>