1 files changed, 4 insertions, 2 deletions

diff --git a/drivers/hwmon/pmbus.c b/drivers/hwmon/pmbus.c
index 98e2e28899e2..b0ea00b75f17 100644
--- a/drivers/hwmon/pmbus.c
+++ b/drivers/hwmon/pmbus.c
@@ -47,12 +47,14 @@ static void pmbus_find_sensor_groups(struct i2c_client *client,
         if (info->func[0]
             && pmbus_check_byte_register(client, 0, PMBUS_STATUS_INPUT))
                 info->func[0] |= PMBUS_HAVE_STATUS_INPUT;
-        if (pmbus_check_word_register(client, 0, PMBUS_READ_FAN_SPEED_1)) {
+        if (pmbus_check_byte_register(client, 0, PMBUS_FAN_CONFIG_12) &&
+            pmbus_check_word_register(client, 0, PMBUS_READ_FAN_SPEED_1)) {
                 info->func[0] |= PMBUS_HAVE_FAN12;
                 if (pmbus_check_byte_register(client, 0, PMBUS_STATUS_FAN_12))
                         info->func[0] |= PMBUS_HAVE_STATUS_FAN12;
         }
-        if (pmbus_check_word_register(client, 0, PMBUS_READ_FAN_SPEED_3)) {
+        if (pmbus_check_byte_register(client, 0, PMBUS_FAN_CONFIG_34) &&
+            pmbus_check_word_register(client, 0, PMBUS_READ_FAN_SPEED_3)) {
                 info->func[0] |= PMBUS_HAVE_FAN34;
                 if (pmbus_check_byte_register(client, 0, PMBUS_STATUS_FAN_34))
                         info->func[0] |= PMBUS_HAVE_STATUS_FAN34;