Re: [PATCH v6 2/2] iio: adc: max14001: New driver

[Jonathan Cameron <jic23@kernel.org>]

On Sat, 17 Jun 2023 19:34:23 +0100
Jonathan Cameron <jic23@kernel.org> wrote:

> On Wed, 14 Jun 2023 14:53:12 +0300
> Andy Shevchenko <andy.shevchenko@gmail.com> wrote:
> 
> > On Wed, Jun 14, 2023 at 1:43 PM Paller, Kim Seer
> > <KimSeer.Paller@analog.com> wrote:  
> > > > From: Andy Shevchenko <andy.shevchenko@gmail.com>
> > > > Sent: Wednesday, June 14, 2023 5:12 PM    
> > 
> > ...
> >   
> > > > > +               /* select external voltage reference source for the ADC */
> > > > > +               ret = max14001_reg_update(st, MAX14001_CFG,
> > > > > +                                         MAX14001_CFG_EXRF, 1);
> > > > > +
> > > > > +               ret = regulator_get_voltage(vref);
> > > > > +               if (ret < 0)
> > > > > +                       return dev_err_probe(dev, ret,
> > > > > +                                            "Failed to get vref\n");    
> > > >
> > > > Is it important to choose the external reference source _before_ getting the
> > > > voltage of the regulator? If not, I would swap these calls, otherwise the
> > > > comment is needed to explain why the sequence is important in the way it's
> > > > written.    
> > >
> > > It is not important. These calls can be swap without any issues.    
> > 
> > If you send a new version, please swap, otherwise I hope Jonathan can
> > do it when applying.
> >   
> 
> I made these changes whilst applying...
> 
> --- a/drivers/iio/adc/max14001.c
> +++ b/drivers/iio/adc/max14001.c
> @@ -290,16 +290,19 @@ static int max14001_probe(struct spi_device *spi)
>                 if (ret)
>                         return ret;
>  
> -               /* select external voltage reference source for the ADC */
> -               ret = max14001_reg_update(st, MAX14001_CFG,
> -                                         MAX14001_CFG_EXRF, 1);
> -
>                 ret = regulator_get_voltage(vref);
>                 if (ret < 0)
>                         return dev_err_probe(dev, ret,
>                                              "Failed to get vref\n");
>  
>                 st->vref_mv = ret / 1000;
> +
> +               /* select external voltage reference source for the ADC */
> +               ret = max14001_reg_update(st, MAX14001_CFG,
> +                                         MAX14001_CFG_EXRF, 1);
> +
> +               if (ret < 0)
> +                       return ret;
>         }
>  
>         mutex_init(&st->lock);
> 
> 
> Note that whilst I've applied this to the togreg branch of iio.git - it is just
> a tiny bit too late to make the merge window that starts in about a week.
> As such I'll only push this out as testing until I can rebase the tree
> on rc1 once available.

Actually nope. Dropped it again because a question came up in my build tests.

I'll address that in a separate reply.

Jonathan

> 
> Thanks,
> 
> Jonathan