diff --git a/mt7921/mac.c b/mt7921/mac.c
index defef349..0744f6e4 100644
--- a/mt7921/mac.c
+++ b/mt7921/mac.c
@@ -1553,6 +1553,14 @@ void mt7921_pm_power_save_work(struct work_struct *work)
 	    dev->fw_assert)
 		goto out;
 
+	if (mutex_is_locked(&dev->mt76.mutex))
+		/* if mt76 mutex is held we should not put the device
+		 * to sleep since we are currently accessing device
+		 * register map. We need to wait for the next power_save
+		 * trigger.
+		 */
+		goto out;
+
 	if (time_is_after_jiffies(dev->pm.last_activity + delta)) {
 		delta = dev->pm.last_activity + delta - jiffies;
 		goto out;