[PATCH] iio: dac: Fix passing uninitialized vref1_uV for no Vref1 case
From: Ariana Lazar
Date: Tue Apr 14 2026 - 08:37:06 EST
Initialize vref1_uV variable to 0 before calling
mcp47feb02_init_ch_scales() in mcp47feb02_probe() to avoid passing an
uninitialized value when have_ext_vref1 is false.
Fixes: dd154646d292 ("iio: dac: mcp47feb02: Fix Vref validation [1-999] case")
Reported-by: Dan Carpenter <error27@xxxxxxxxx>
Closes: https://lore.kernel.org/all/adiPnla0M5EzvgD-@stanley.mountain/
Signed-off-by: Ariana Lazar <ariana.lazar@xxxxxxxxxxxxx>
---
drivers/iio/dac/mcp47feb02.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/drivers/iio/dac/mcp47feb02.c b/drivers/iio/dac/mcp47feb02.c
index faccb804a5ed548088aaf83266b16ed45a92916c..efd4847913e46a4fa1b671aa9c5bd3e1430406b7 100644
--- a/drivers/iio/dac/mcp47feb02.c
+++ b/drivers/iio/dac/mcp47feb02.c
@@ -1095,9 +1095,10 @@ static int mcp47feb02_probe(struct i2c_client *client)
{
const struct mcp47feb02_features *chip_features;
struct device *dev = &client->dev;
+ int vdd_uV, vref_uV, vref1_uV;
struct mcp47feb02_data *data;
struct iio_dev *indio_dev;
- int vref1_uV, vref_uV, vdd_uV, ret;
+ int ret;
indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
if (!indio_dev)
@@ -1146,13 +1147,13 @@ static int mcp47feb02_probe(struct i2c_client *client)
dev_dbg(dev, "Vref is unavailable.\n");
}
+ vref1_uV = 0;
if (chip_features->have_ext_vref1) {
ret = devm_regulator_get_enable_read_voltage(dev, "vref1");
if (ret > 0) {
vref1_uV = ret;
data->use_vref1 = true;
} else {
- vref1_uV = 0;
dev_dbg(dev, "using internal band gap as voltage reference 1.\n");
dev_dbg(dev, "Vref1 is unavailable.\n");
}
---
base-commit: 51e7665ab81f02adc80a1219c260ee678e9c6eb8
change-id: 20260414-mcp47feb02-fix4-614de9334f22
Best regards,
--
Ariana Lazar <ariana.lazar@xxxxxxxxxxxxx>