diff --git a/drivers/hwmon/pmbus/q54sj108a2.c b/drivers/hwmon/pmbus/q54sj108a2.c
index aec512766c319..0976268b2670b 100644
--- a/drivers/hwmon/pmbus/q54sj108a2.c
+++ b/drivers/hwmon/pmbus/q54sj108a2.c
@@ -299,7 +299,7 @@ static int q54sj108a2_probe(struct i2c_client *client)
 		dev_err(&client->dev, "Failed to read Manufacturer ID\n");
 		return ret;
 	}
-	if (ret != 5 || strncmp(buf, "DELTA", 5)) {
+	if (ret != 6 || strncmp(buf, "DELTA", 5)) {
 		buf[ret] = '\0';
 		dev_err(dev, "Unsupported Manufacturer ID '%s'\n", buf);
 		return -ENODEV;