Re: [PATCH 2/3] iio: dac: ad3552r: add support for ad3541r and ad3551r

[Angelo Dureghello <adureghello@xxxxxxxxxxxx>]

Hi David,

On 10/05/24 5:42 PM, David Lechner wrote:
> On Fri, May 10, 2024 at 9:19 AM Angelo Dureghello
> <adureghello@xxxxxxxxxxxx> wrote:
> > From: Angelo Dureghello <adureghello@xxxxxxxxxxxx>
> >
> > Add support for single-output dac variants.
> >
> > Signed-off-by: Angelo Dureghello <adureghello@xxxxxxxxxxxx>
> > ---
> >   drivers/iio/dac/ad3552r.c | 39 +++++++++++++++++++++++++++++----------
> >   1 file changed, 29 insertions(+), 10 deletions(-)
> >
> > diff --git a/drivers/iio/dac/ad3552r.c b/drivers/iio/dac/ad3552r.c
> > index a492e8f2fc0f..0dd6f995c3e2 100644
> > --- a/drivers/iio/dac/ad3552r.c
> > +++ b/drivers/iio/dac/ad3552r.c
> > @@ -140,7 +140,9 @@ enum ad3552r_ch_vref_select {
> >   };
> >
> >   enum ad3542r_id {
> > +       AD3541R_ID = 0x400b,
> >          AD3542R_ID = 0x4009,
> > +       AD3551R_ID = 0x400a,
> >          AD3552R_ID = 0x4008,
> >   };
> >
> > @@ -745,7 +747,8 @@ static void ad3552r_calc_gain_and_offset(struct ad3552r_desc *dac, s32 ch)
> >          } else {
> >                  /* Normal range */
> >                  idx = dac->ch_data[ch].range;
> > -               if (dac->chip_id == AD3542R_ID) {
> > +               if (dac->chip_id == AD3541R_ID ||
> > +                   dac->chip_id == AD3542R_ID) {
> >                          v_min = ad3542r_ch_ranges[idx][0];
> >                          v_max = ad3542r_ch_ranges[idx][1];
> >                  } else {
> > @@ -780,7 +783,7 @@ static int ad3552r_find_range(u16 id, s32 *vals)
> >          int i, len;
> >          const s32 (*ranges)[2];
> >
> > -       if (id == AD3542R_ID) {
> > +       if (id == AD3541R_ID || id == AD3542R_ID) {
> >                  len = ARRAY_SIZE(ad3542r_ch_ranges);
> >                  ranges = ad3542r_ch_ranges;
> >          } else {
> > @@ -955,9 +958,10 @@ static int ad3552r_configure_device(struct ad3552r_desc *dac)
> >                          dev_err(dev, "mandatory reg property missing\n");
> >                          goto put_child;
> >                  }
> > -               if (ch >= AD3552R_NUM_CH) {
> > -                       dev_err(dev, "reg must be less than %d\n",
> > -                               AD3552R_NUM_CH);
> > +               if (ch >= AD3552R_NUM_CH ||
> > +                       (dac->chip_id == AD3541R_ID && ch) ||
> > +                       (dac->chip_id == AD3551R_ID && ch)) {
> > +                       dev_err(dev, "channel %d is not supported\n", ch);
> >                          err = -EINVAL;
> >                          goto put_child;
> >                  }
> > @@ -987,9 +991,10 @@ static int ad3552r_configure_device(struct ad3552r_desc *dac)
> >                                  goto put_child;
> >
> >                          dac->ch_data[ch].range = val;
> > -               } else if (dac->chip_id == AD3542R_ID) {
> > +               } else if (dac->chip_id == AD3541R_ID ||
> > +                          dac->chip_id == AD3542R_ID) {
> >                          dev_err(dev,
> > -                               "adi,output-range-microvolt is required for ad3542r\n");
> > +                               "adi,output-range-microvolt is required for ad354xr\n");
> >                          err = -EINVAL;
> >                          goto put_child;
> >                  } else {
> > @@ -1088,10 +1093,20 @@ static int ad3552r_probe(struct spi_device *spi)
> >                  return err;
> >
> >          /* Config triggered buffer device */
> > -       if (dac->chip_id == AD3552R_ID)
> > -               indio_dev->name = "ad3552r";
> > -       else
> > +       switch (dac->chip_id) {
> > +       case AD3541R_ID:
> > +               indio_dev->name = "ad3541r";
> > +               break;
> > +       case AD3542R_ID:
> >                  indio_dev->name = "ad3542r";
> > +               break;
> > +       case AD3551R_ID:
> > +               indio_dev->name = "ad3551r";
> > +               break;
> > +       case AD3552R_ID:
> > +               indio_dev->name = "ad3552r";
> > +               break;
> > +       }
> >          indio_dev->dev.parent = &spi->dev;
> >          indio_dev->info = &ad3552r_iio_info;
> >          indio_dev->num_channels = dac->num_ch;
> > @@ -1110,14 +1125,18 @@ static int ad3552r_probe(struct spi_device *spi)
> >   }
> >
> >   static const struct spi_device_id ad3552r_id[] = {
> > +       { "ad3541r", AD3541R_ID },
> >          { "ad3542r", AD3542R_ID },
> > +       { "ad3551r", AD3551R_ID },
> >          { "ad3552r", AD3552R_ID },
> >          { }
> >   };
> >   MODULE_DEVICE_TABLE(spi, ad3552r_id);
> >
> >   static const struct of_device_id ad3552r_of_match[] = {
> > +       { .compatible = "adi,ad3541r"},
> >          { .compatible = "adi,ad3542r"},
> > +       { .compatible = "adi,ad3551r"},
> >          { .compatible = "adi,ad3552r"},
> >          { }
> >   };
> > --
> > 2.45.0.rc1
> It looks like it is time for a chip_info struct here instead of the if
> and switch statements to get chip-specific data. Most other IIO
> drivers have this already and it is the preferred way to look up this
> kind of information in the IIO subsystem. I prefer the drivers that
> don't put all of the info structs in an array (that way the code is
> less verbose). So I would suggest looking at e.g. adc/aspeed_adc,
> starting with aspeed_adc_matches, to see what I mean and how to
> implement it. (So one patch to add the info structs and a second patch
> to add the single channel chips)

Ack, will change in that way.


Regards,
angelo