media: ov8856: Add runtime PM callbacks

There were no runtime PM callbacks registered, leaving regulators being
enabled while the device is suspended on DT systems. Adjust and register
existing power controlling functions to turn them off/on.
Signed-off-by: Hidenori Kobayashi <hidenorik@chromium.org>
Reviewed-by: Tomasz Figa <tfiga@chromium.org>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>

drivers/media/i2c/ov8856.c

@@ -2110,17 +2110,18 @@ static int ov8856_set_stream(struct v4l2_subdev *sd, int enable)
 	return ret;
 }
 
-static int __ov8856_power_on(struct ov8856 *ov8856)
+static int ov8856_power_on(struct device *dev)
 {
-	struct i2c_client *client = v4l2_get_subdevdata(&ov8856->sd);
+	struct v4l2_subdev *sd = dev_get_drvdata(dev);
+	struct ov8856 *ov8856 = to_ov8856(sd);
 	int ret;
 
-	if (is_acpi_node(dev_fwnode(&client->dev)))
+	if (is_acpi_node(dev_fwnode(dev)))
 		return 0;
 
 	ret = clk_prepare_enable(ov8856->xvclk);
 	if (ret < 0) {
-		dev_err(&client->dev, "failed to enable xvclk\n");
+		dev_err(dev, "failed to enable xvclk\n");
 		return ret;
 	}
 
@@ -2132,7 +2133,7 @@ static int __ov8856_power_on(struct ov8856 *ov8856)
 	ret = regulator_bulk_enable(ARRAY_SIZE(ov8856_supply_names),
 				    ov8856->supplies);
 	if (ret < 0) {
-		dev_err(&client->dev, "failed to enable regulators\n");
+		dev_err(dev, "failed to enable regulators\n");
 		goto disable_clk;
 	}
 
@@ -2148,17 +2149,20 @@ static int __ov8856_power_on(struct ov8856 *ov8856)
 	return ret;
 }
 
-static void __ov8856_power_off(struct ov8856 *ov8856)
+static int ov8856_power_off(struct device *dev)
 {
-	struct i2c_client *client = v4l2_get_subdevdata(&ov8856->sd);
+	struct v4l2_subdev *sd = dev_get_drvdata(dev);
+	struct ov8856 *ov8856 = to_ov8856(sd);
 
-	if (is_acpi_node(dev_fwnode(&client->dev)))
-		return;
+	if (is_acpi_node(dev_fwnode(dev)))
+		return 0;
 
 	gpiod_set_value_cansleep(ov8856->reset_gpio, 1);
 	regulator_bulk_disable(ARRAY_SIZE(ov8856_supply_names),
 			       ov8856->supplies);
 	clk_disable_unprepare(ov8856->xvclk);
+
+	return 0;
 }
 
 static int __maybe_unused ov8856_suspend(struct device *dev)
@@ -2170,7 +2174,7 @@ static int __maybe_unused ov8856_suspend(struct device *dev)
 	if (ov8856->streaming)
 		ov8856_stop_streaming(ov8856);
 
-	__ov8856_power_off(ov8856);
+	ov8856_power_off(dev);
 	mutex_unlock(&ov8856->mutex);
 
 	return 0;
@@ -2184,7 +2188,7 @@ static int __maybe_unused ov8856_resume(struct device *dev)
 
 	mutex_lock(&ov8856->mutex);
 
-	__ov8856_power_on(ov8856);
+	ov8856_power_on(dev);
 	if (ov8856->streaming) {
 		ret = ov8856_start_streaming(ov8856);
 		if (ret) {
@@ -2451,7 +2455,7 @@ static void ov8856_remove(struct i2c_client *client)
 	pm_runtime_disable(&client->dev);
 	mutex_destroy(&ov8856->mutex);
 
-	__ov8856_power_off(ov8856);
+	ov8856_power_off(&client->dev);
 }
 
 static int ov8856_probe(struct i2c_client *client)
@@ -2475,7 +2479,7 @@ static int ov8856_probe(struct i2c_client *client)
 
 	full_power = acpi_dev_state_d0(&client->dev);
 	if (full_power) {
-		ret = __ov8856_power_on(ov8856);
+		ret = ov8856_power_on(&client->dev);
 		if (ret) {
 			dev_err(&client->dev, "failed to power on\n");
 			return ret;
@@ -2531,13 +2535,14 @@ static int ov8856_probe(struct i2c_client *client)
 	mutex_destroy(&ov8856->mutex);
 
 probe_power_off:
-	__ov8856_power_off(ov8856);
+	ov8856_power_off(&client->dev);
 
 	return ret;
 }
 
 static const struct dev_pm_ops ov8856_pm_ops = {
 	SET_SYSTEM_SLEEP_PM_OPS(ov8856_suspend, ov8856_resume)
+	SET_RUNTIME_PM_OPS(ov8856_power_off, ov8856_power_on, NULL)
 };
 
 #ifdef CONFIG_ACPI