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Subject[PATCH] iio: ad5380: Fix probe failure when no external reference is supplied
From: Pawel Grudzinski <>

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.

Signed-off-by: Paweł Grudziński <>
There are couple more places where I suspect similar issue with devices
having integrated reference, but I am sending this one because I tested it
with hardware. If this gets accepted, I will look through other drivers
obtaining Vref in same manner.

drivers/iio/dac/ad5380.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iio/dac/ad5380.c b/drivers/iio/dac/ad5380.c
index 97d2c51..257d455 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) {
Best regards,
Paweł Grudziński

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