diff --git a/drivers/iio/dac/max5821.c b/drivers/iio/dac/max5821.c
index e7e29359f8fe..dd4e35460195 100644
--- a/drivers/iio/dac/max5821.c
+++ b/drivers/iio/dac/max5821.c
@@ -90,6 +90,7 @@ static int max5821_sync_powerdown_mode(struct max5821_data *data,
 				       const struct iio_chan_spec *chan)
 {
 	u8 outbuf[2];
+	int ret;
 
 	outbuf[0] = MAX5821_EXTENDED_COMMAND_MODE;
 
@@ -103,7 +104,13 @@ static int max5821_sync_powerdown_mode(struct max5821_data *data,
 	else
 		outbuf[1] |= MAX5821_EXTENDED_POWER_UP;
 
-	return i2c_master_send(data->client, outbuf, 2);
+	ret = i2c_master_send(data->client, outbuf, sizeof(outbuf));
+	if (ret < 0)
+		return ret;
+	if (ret != sizeof(outbuf))
+		return -EIO;
+
+	return 0;
 }
 
 static ssize_t max5821_write_dac_powerdown(struct iio_dev *indio_dev,