On 19/07/16 07:12, Paweł Grudziński wrote: > From: Pawel Grudzinski <[email protected]> > > Driver fails to load when there is no external Vref regulator defined, > leaving no way to use internal reference. ad5380_probe function tries to > obtain regulator with demv_regulator_get and checks for error, in which > case it would use internal reference. Even without "Vref" regulator defined > devm_regulator_get returns dummy regulator which makes function omit use of > internal reference and causes failure on regulator_get_voltage. > > Replace demv_regulator_get with demv_regulator_get_optional, which returns > error instead of dummy regulator if it does not find one which is specified > by the caller to make ad5380_probe configure internal reference when no > "Vref" regulator is supplied. > > Initialize internal regulator only if returned error is ENODEV, otherwise > propagate the error to the caller of probe. > > Signed-off-by: Paweł Grudziński <[email protected]> > --- > Changes in v2: > - Add error type checking to enable internal reference only on ENODEV and > return any other error to the caller. > > drivers/iio/dac/ad5380.c | 11 ++++++++--- > 1 file changed, 8 insertions(+), 3 deletions(-) > > diff --git a/drivers/iio/dac/ad5380.c b/drivers/iio/dac/ad5380.c > index 97d2c51..144cfdc 100644 > --- a/drivers/iio/dac/ad5380.c > +++ b/drivers/iio/dac/ad5380.c > @@ -401,7 +401,7 @@ static int ad5380_probe(struct device *dev, struct regmap > *regmap, > if (st->chip_info->int_vref == 2500) > ctrl |= AD5380_CTRL_INT_VREF_2V5; > > - st->vref_reg = devm_regulator_get(dev, "vref"); > + st->vref_reg = devm_regulator_get_optional(dev, "vref"); > if (!IS_ERR(st->vref_reg)) { > ret = regulator_enable(st->vref_reg); > if (ret) { > @@ -416,8 +416,13 @@ static int ad5380_probe(struct device *dev, struct > regmap *regmap, > > st->vref = ret / 1000; > } else { > - st->vref = st->chip_info->int_vref; > - ctrl |= AD5380_CTRL_INT_VREF_EN; > + if (PTR_ERR(st->vref_reg) == -ENODEV) { > + st->vref = st->chip_info->int_vref; > + ctrl |= AD5380_CTRL_INT_VREF_EN; > + } else { > + ret = st->vref_reg; Autobuilder picked it up an issue. This should be ret = PTR_ERR(st->vref_reg) I think?
Jonathan > + goto error_free_reg; > + } > } > > ret = regmap_write(st->regmap, AD5380_REG_SF_CTRL, ctrl); >
