iio: adc: modify NPCM ADC read reference voltage

commit 4e63ed6b90803eeb400c392e9ff493200d926b06 upstream.

Checking if regulator is valid before reading
NPCM ADC regulator voltage to avoid system crash
in a case the regulator is not valid.

Signed-off-by: Tomer Maimon <tmaimon77@gmail.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/iio/adc/npcm_adc.c b/drivers/iio/adc/npcm_adc.c
index 9e25bbec9c70bc96c78d51df3d220c0871db612c..193b3b81de4d31775fde5bc7b0ea801c330073dd 100644 (file)
--- a/drivers/iio/adc/npcm_adc.c
+++ b/drivers/iio/adc/npcm_adc.c
@@ -149,7 +149,7 @@ static int npcm_adc_read_raw(struct iio_dev *indio_dev,
                }
                return IIO_VAL_INT;
        case IIO_CHAN_INFO_SCALE:
-               if (info->vref) {
+               if (!IS_ERR(info->vref)) {
                        vref_uv = regulator_get_voltage(info->vref);
                        *val = vref_uv / 1000;
                } else {