diff --git a/mt7915/init.c b/mt7915/init.c
index ec297e04..526f0fab 100644
--- a/mt7915/init.c
+++ b/mt7915/init.c
@@ -89,6 +89,7 @@ static ssize_t mt7915_thermal_temp_store(struct device *dev,
 	     val < phy->throttle_temp[MT7915_CRIT_TEMP_IDX])) {
 		dev_err(phy->dev->mt76.dev,
 			"temp1_max shall be greater than temp1_crit.");
+		mutex_unlock(&phy->dev->mt76.mutex);
 		return -EINVAL;
 	}