Re: [PATCH v6 5/9] iio: adc: ad7173: refactor ain and vref selection

From: Nuno Sá
Date: Fri Jun 07 2024 - 06:21:56 EST


On Fri, 2024-06-07 at 12:37 +0300, Ceclan, Dumitru wrote:
> On 07/06/2024 12:04, Nuno Sá wrote:
> > On Thu, 2024-06-06 at 19:07 +0300, Dumitru Ceclan via B4 Relay wrote:
> > > From: Dumitru Ceclan <dumitru.ceclan@xxxxxxxxxx>
> > >
> > > Move validation of analog inputs and reference voltage selection to
> > > separate functions to reduce the size of the channel config parsing
> > > function and improve readability.
> > > Add defines for the number of analog inputs in a channel.
> > >
> > > Signed-off-by: Dumitru Ceclan <dumitru.ceclan@xxxxxxxxxx>
> > > ---
> > >  drivers/iio/adc/ad7173.c | 68 +++++++++++++++++++++++++++++++++----------
> > > ----
> > > -
> > >  1 file changed, 47 insertions(+), 21 deletions(-)
> > >
> > > diff --git a/drivers/iio/adc/ad7173.c b/drivers/iio/adc/ad7173.c
> > > index 8631f218b69e..4040edbd1c32 100644
> > > --- a/drivers/iio/adc/ad7173.c
> > > +++ b/drivers/iio/adc/ad7173.c
> > > @@ -60,6 +60,7 @@
> > >  #define AD7173_CH_SETUP_AINPOS_MASK GENMASK(9, 5)
> > >  #define AD7173_CH_SETUP_AINNEG_MASK GENMASK(4, 0)
> > >  
> > > +#define AD7173_NO_AINS_PER_CHANNEL 2
> > >  #define AD7173_CH_ADDRESS(pos, neg) \
> > >   (FIELD_PREP(AD7173_CH_SETUP_AINPOS_MASK, pos) | \
> > >   FIELD_PREP(AD7173_CH_SETUP_AINNEG_MASK, neg))
> > > @@ -629,6 +630,7 @@ static int ad7173_setup(struct iio_dev *indio_dev)
> > >  static unsigned int ad7173_get_ref_voltage_milli(struct ad7173_state *st,
> > >   u8 reference_select)
> > >  {
> > > + struct device *dev = &st->sd.spi->dev;
> > >   int vref;
> > >  
> > >   switch (reference_select) {
> > > @@ -652,9 +654,11 @@ static unsigned int
> > > ad7173_get_ref_voltage_milli(struct
> > > ad7173_state *st,
> > >   return -EINVAL;
> > >   }
> > >  
> > > - if (vref < 0)
> > > + if (vref < 0) {
> > > + dev_err(dev, "Cannot use reference %u. Error:%d\n",
> > > + reference_select, vref);
> > >   return vref;
> > > -
> > > + }
> > >   return vref / (MICRO / MILLI);
> > >  }
> >
> > unrelated?
> >
> > - Nuno Sá
> >
>
> Hmm, maybe I misunderstood "Any error log needed should be done inside
> ad7173_get_ref_voltage_milli()"
> https://lore.kernel.org/all/71452f6882efe6a181d477914488617d28a38e2f.camel@xxxxxxxxx/
>
> This change should be in a different patch or should it not've been done
> this way?

Ohh right... Mentioning this particular log change in the commit message would
avoid my question. Also, note that you're still doing:

ret = ad7173_get_ref_voltage_milli(st, ref_sel);
if (ret < 0)
return ret;

instead of:

return ad7173_get_ref_voltage_milli(...)

which defeats the purpose of having the log inside
ad7173_get_ref_voltage_milli()

But after stepping back I see ad7173_get_ref_voltage_milli() is also being used
in a non probe path. Hence, doing the log out of the function using
dev_err_probe() may be reason enough to keep things as you had before my
comments. Will leave that up to you (sorry for the noise).

- Nuno Sá