drm/panfrost: properly handle error in probe

Introduce a boolean to know if opp table has been added.

With this, we can call panfrost_devfreq_fini() in case of error
and release what has been initialised.
Reviewed-by: Steven Price <steven.price@arm.com>
Reviewed-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Signed-off-by: Clément Péron <peron.clem@gmail.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200710095409.407087-7-peron.clem@gmail.com

drivers/gpu/drm/panfrost/panfrost_devfreq.c

@@ -101,6 +101,7 @@ int panfrost_devfreq_init(struct panfrost_device *pfdev)
 		return 0;
 	else if (ret)
 		return ret;
+	pfdevfreq->opp_of_table_added = true;
 
 	spin_lock_init(&pfdevfreq->lock);
 
@@ -109,8 +110,10 @@ int panfrost_devfreq_init(struct panfrost_device *pfdev)
 	cur_freq = clk_get_rate(pfdev->clock);
 
 	opp = devfreq_recommended_opp(dev, &cur_freq, 0);
-	if (IS_ERR(opp))
-		return PTR_ERR(opp);
+	if (IS_ERR(opp)) {
+		ret = PTR_ERR(opp);
+		goto err_fini;
+	}
 
 	panfrost_devfreq_profile.initial_freq = cur_freq;
 	dev_pm_opp_put(opp);
@@ -119,8 +122,8 @@ int panfrost_devfreq_init(struct panfrost_device *pfdev)
 					  DEVFREQ_GOV_SIMPLE_ONDEMAND, NULL);
 	if (IS_ERR(devfreq)) {
 		DRM_DEV_ERROR(dev, "Couldn't initialize GPU devfreq\n");
-		dev_pm_opp_of_remove_table(dev);
-		return PTR_ERR(devfreq);
+		ret = PTR_ERR(devfreq);
+		goto err_fini;
 	}
 	pfdevfreq->devfreq = devfreq;
 
@@ -131,15 +134,25 @@ int panfrost_devfreq_init(struct panfrost_device *pfdev)
 		pfdevfreq->cooling = cooling;
 
 	return 0;
+
+err_fini:
+	panfrost_devfreq_fini(pfdev);
+	return ret;
 }
 
 void panfrost_devfreq_fini(struct panfrost_device *pfdev)
 {
 	struct panfrost_devfreq *pfdevfreq = &pfdev->pfdevfreq;
 
-	if (pfdevfreq->cooling)
+	if (pfdevfreq->cooling) {
 		devfreq_cooling_unregister(pfdevfreq->cooling);
-	dev_pm_opp_of_remove_table(&pfdev->pdev->dev);
+		pfdevfreq->cooling = NULL;
+	}
+
+	if (pfdevfreq->opp_of_table_added) {
+		dev_pm_opp_of_remove_table(&pfdev->pdev->dev);
+		pfdevfreq->opp_of_table_added = false;
+	}
 }
 
 void panfrost_devfreq_resume(struct panfrost_device *pfdev)

drivers/gpu/drm/panfrost/panfrost_devfreq.h

@@ -15,6 +15,7 @@ struct panfrost_device;
 struct panfrost_devfreq {
 	struct devfreq *devfreq;
 	struct thermal_cooling_device *cooling;
+	bool opp_of_table_added;
 
 	ktime_t busy_time;
 	ktime_t idle_time;