[PATCH 2/2] drm/panfrost: add devfreq regulator support

[Clément Péron]

OPP table can defined both frequency and voltage.

Register the mali regulator if it exist.

Signed-off-by: Clément Péron <peron.clem at gmail.com>
---
 drivers/gpu/drm/panfrost/panfrost_devfreq.c | 34 ++++++++++++++++++---
 drivers/gpu/drm/panfrost/panfrost_device.h  |  1 +
 2 files changed, 31 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/panfrost/panfrost_devfreq.c b/drivers/gpu/drm/panfrost/panfrost_devfreq.c
index 62541f4edd81..2dc8e2355358 100644
--- a/drivers/gpu/drm/panfrost/panfrost_devfreq.c
+++ b/drivers/gpu/drm/panfrost/panfrost_devfreq.c
@@ -78,12 +78,26 @@ int panfrost_devfreq_init(struct panfrost_device *pfdev)
 	struct device *dev = &pfdev->pdev->dev;
 	struct devfreq *devfreq;
 	struct thermal_cooling_device *cooling;
+	const char *mali = "mali";
+	struct opp_table *opp_table = NULL;
+
+	/* Regulator is optional */
+	opp_table = dev_pm_opp_set_regulators(dev, &mali, 1);
+	if (IS_ERR(opp_table)) {
+		ret = PTR_ERR(opp_table);
+		if (ret != -ENODEV) {
+			DRM_DEV_ERROR(dev, "Failed to set regulator: %d\n", ret);
+			return ret;
+		}
+	}
+	pfdev->devfreq.opp_table = opp_table;
 
 	ret = dev_pm_opp_of_add_table(dev);
-	if (ret == -ENODEV) /* Optional, continue without devfreq */
-		return 0;
-	else if (ret)
-		return ret;
+	if (ret) {
+		if (ret == -ENODEV) /* Optional, continue without devfreq */
+			ret = 0;
+		goto err_opp_reg;
+	}
 
 	panfrost_devfreq_reset(pfdev);
 
@@ -119,6 +133,12 @@ int panfrost_devfreq_init(struct panfrost_device *pfdev)
 err_opp:
 	dev_pm_opp_of_remove_table(dev);
 
+err_opp_reg:
+	if (pfdev->devfreq.opp_table) {
+		dev_pm_opp_put_regulators(pfdev->devfreq.opp_table);
+		pfdev->devfreq.opp_table = NULL;
+	}
+
 	return ret;
 }
 
@@ -126,7 +146,13 @@ void panfrost_devfreq_fini(struct panfrost_device *pfdev)
 {
 	if (pfdev->devfreq.cooling)
 		devfreq_cooling_unregister(pfdev->devfreq.cooling);
+
 	dev_pm_opp_of_remove_table(&pfdev->pdev->dev);
+
+	if (pfdev->devfreq.opp_table) {
+		dev_pm_opp_put_regulators(pfdev->devfreq.opp_table);
+		pfdev->devfreq.opp_table = NULL;
+	}
 }
 
 void panfrost_devfreq_resume(struct panfrost_device *pfdev)
diff --git a/drivers/gpu/drm/panfrost/panfrost_device.h b/drivers/gpu/drm/panfrost/panfrost_device.h
index 06713811b92c..f6b0c779dfe5 100644
--- a/drivers/gpu/drm/panfrost/panfrost_device.h
+++ b/drivers/gpu/drm/panfrost/panfrost_device.h
@@ -86,6 +86,7 @@ struct panfrost_device {
 	struct {
 		struct devfreq *devfreq;
 		struct thermal_cooling_device *cooling;
+		struct opp_table *opp_table;
 		ktime_t busy_time;
 		ktime_t idle_time;
 		ktime_t time_last_update;
-- 
2.20.1