1 files changed, 22 insertions, 2 deletions

diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
index 2951a87cc..344e27616 100644
--- a/drivers/devfreq/devfreq.c
+++ b/drivers/devfreq/devfreq.c
@@ -461,10 +461,14 @@ static void devfreq_monitor(struct work_struct *work)
 	if (err)
 		dev_err(&devfreq->dev, "dvfs failed with (%d) error\n", err);
 
+	if (devfreq->stop_polling)
+		goto out;
+
 	queue_delayed_work(devfreq_wq, &devfreq->work,
 				msecs_to_jiffies(devfreq->profile->polling_ms));
-	mutex_unlock(&devfreq->lock);
 
+out:
+	mutex_unlock(&devfreq->lock);
 	trace_devfreq_monitor(devfreq);
 }
 
@@ -482,6 +486,10 @@ void devfreq_monitor_start(struct devfreq *devfreq)
 	if (IS_SUPPORTED_FLAG(devfreq->governor->flags, IRQ_DRIVEN))
 		return;
 
+	mutex_lock(&devfreq->lock);
+	if (delayed_work_pending(&devfreq->work))
+		goto out;
+
 	switch (devfreq->profile->timer) {
 	case DEVFREQ_TIMER_DEFERRABLE:
 		INIT_DEFERRABLE_WORK(&devfreq->work, devfreq_monitor);
@@ -490,12 +498,16 @@ void devfreq_monitor_start(struct devfreq *devfreq)
 		INIT_DELAYED_WORK(&devfreq->work, devfreq_monitor);
 		break;
 	default:
-		return;
+		goto out;
 	}
 
 	if (devfreq->profile->polling_ms)
 		queue_delayed_work(devfreq_wq, &devfreq->work,
 			msecs_to_jiffies(devfreq->profile->polling_ms));
+
+out:
+	devfreq->stop_polling = false;
+	mutex_unlock(&devfreq->lock);
 }
 EXPORT_SYMBOL(devfreq_monitor_start);
 
@@ -512,6 +524,14 @@ void devfreq_monitor_stop(struct devfreq *devfreq)
 	if (IS_SUPPORTED_FLAG(devfreq->governor->flags, IRQ_DRIVEN))
 		return;
 
+	mutex_lock(&devfreq->lock);
+	if (devfreq->stop_polling) {
+		mutex_unlock(&devfreq->lock);
+		return;
+	}
+
+	devfreq->stop_polling = true;
+	mutex_unlock(&devfreq->lock);
 	cancel_delayed_work_sync(&devfreq->work);
 }
 EXPORT_SYMBOL(devfreq_monitor_stop);