diff --git a/drivers/thermal/cpu_cooling.c b/drivers/thermal/cpu_cooling.c
index 91048eeca28b..69d0f430b2d1 100644
--- a/drivers/thermal/cpu_cooling.c
+++ b/drivers/thermal/cpu_cooling.c
@@ -107,8 +107,6 @@ struct cpufreq_cooling_device {
 };
 static DEFINE_IDA(cpufreq_ida);
 
-static unsigned int cpufreq_dev_count;
-
 static DEFINE_MUTEX(cooling_list_lock);
 static LIST_HEAD(cpufreq_dev_list);
 
@@ -395,13 +393,20 @@ static int get_static_power(struct cpufreq_cooling_device *cpufreq_device,
 
 	opp = dev_pm_opp_find_freq_exact(cpufreq_device->cpu_dev, freq_hz,
 					 true);
+	if (IS_ERR(opp)) {
+		dev_warn_ratelimited(cpufreq_device->cpu_dev,
+				     "Failed to find OPP for frequency %lu: %ld\n",
+				     freq_hz, PTR_ERR(opp));
+		return -EINVAL;
+	}
+
 	voltage = dev_pm_opp_get_voltage(opp);
 	dev_pm_opp_put(opp);
 
 	if (voltage == 0) {
-		dev_warn_ratelimited(cpufreq_device->cpu_dev,
-				     "Failed to get voltage for frequency %lu: %ld\n",
-				     freq_hz, IS_ERR(opp) ? PTR_ERR(opp) : 0);
+		dev_err_ratelimited(cpufreq_device->cpu_dev,
+				    "Failed to get voltage for frequency %lu\n",
+				    freq_hz);
 		return -EINVAL;
 	}
 
@@ -693,9 +698,9 @@ static int cpufreq_power2state(struct thermal_cooling_device *cdev,
 
 	*state = cpufreq_cooling_get_level(cpu, target_freq);
 	if (*state == THERMAL_CSTATE_INVALID) {
-		dev_warn_ratelimited(&cdev->device,
-				     "Failed to convert %dKHz for cpu %d into a cdev state\n",
-				     target_freq, cpu);
+		dev_err_ratelimited(&cdev->device,
+				    "Failed to convert %dKHz for cpu %d into a cdev state\n",
+				    target_freq, cpu);
 		return -EINVAL;
 	}
 
@@ -771,6 +776,7 @@ __cpufreq_cooling_register(struct device_node *np,
 	unsigned int freq, i, num_cpus;
 	int ret;
 	struct thermal_cooling_device_ops *cooling_ops;
+	bool first;
 
 	if (!alloc_cpumask_var(&temp_mask, GFP_KERNEL))
 		return ERR_PTR(-ENOMEM);
@@ -874,13 +880,14 @@ __cpufreq_cooling_register(struct device_node *np,
 	cpufreq_dev->cool_dev = cool_dev;
 
 	mutex_lock(&cooling_list_lock);
-	list_add(&cpufreq_dev->node, &cpufreq_dev_list);
-
 	/* Register the notifier for first cpufreq cooling device */
-	if (!cpufreq_dev_count++)
+	first = list_empty(&cpufreq_dev_list);
+	list_add(&cpufreq_dev->node, &cpufreq_dev_list);
+	mutex_unlock(&cooling_list_lock);
+
+	if (first)
 		cpufreq_register_notifier(&thermal_cpufreq_notifier_block,
 					  CPUFREQ_POLICY_NOTIFIER);
-	mutex_unlock(&cooling_list_lock);
 
 	goto put_policy;
 
@@ -1021,6 +1028,7 @@ EXPORT_SYMBOL(of_cpufreq_power_cooling_register);
 void cpufreq_cooling_unregister(struct thermal_cooling_device *cdev)
 {
 	struct cpufreq_cooling_device *cpufreq_dev;
+	bool last;
 
 	if (!cdev)
 		return;
@@ -1028,14 +1036,15 @@ void cpufreq_cooling_unregister(struct thermal_cooling_device *cdev)
 	cpufreq_dev = cdev->devdata;
 
 	mutex_lock(&cooling_list_lock);
+	list_del(&cpufreq_dev->node);
 	/* Unregister the notifier for the last cpufreq cooling device */
-	if (!--cpufreq_dev_count)
+	last = list_empty(&cpufreq_dev_list);
+	mutex_unlock(&cooling_list_lock);
+
+	if (last)
 		cpufreq_unregister_notifier(&thermal_cpufreq_notifier_block,
 					    CPUFREQ_POLICY_NOTIFIER);
 
-	list_del(&cpufreq_dev->node);
-	mutex_unlock(&cooling_list_lock);
-
 	thermal_cooling_device_unregister(cpufreq_dev->cool_dev);
 	ida_simple_remove(&cpufreq_ida, cpufreq_dev->id);
 	kfree(cpufreq_dev->dyn_power_table);
diff --git a/drivers/thermal/devfreq_cooling.c b/drivers/thermal/devfreq_cooling.c
index 7743a78d4723..4bf4ad58cffd 100644
--- a/drivers/thermal/devfreq_cooling.c
+++ b/drivers/thermal/devfreq_cooling.c
@@ -186,16 +186,22 @@ get_static_power(struct devfreq_cooling_device *dfc, unsigned long freq)
 		return 0;
 
 	opp = dev_pm_opp_find_freq_exact(dev, freq, true);
-	if (IS_ERR(opp) && (PTR_ERR(opp) == -ERANGE))
+	if (PTR_ERR(opp) == -ERANGE)
 		opp = dev_pm_opp_find_freq_exact(dev, freq, false);
 
+	if (IS_ERR(opp)) {
+		dev_err_ratelimited(dev, "Failed to find OPP for frequency %lu: %ld\n",
+				    freq, PTR_ERR(opp));
+		return 0;
+	}
+
 	voltage = dev_pm_opp_get_voltage(opp) / 1000; /* mV */
 	dev_pm_opp_put(opp);
 
 	if (voltage == 0) {
-		dev_warn_ratelimited(dev,
-				     "Failed to get voltage for frequency %lu: %ld\n",
-				     freq, IS_ERR(opp) ? PTR_ERR(opp) : 0);
+		dev_err_ratelimited(dev,
+				    "Failed to get voltage for frequency %lu\n",
+				    freq);
 		return 0;
 	}