thermal: rcar: enable to use thermal-zone on DT

This patch enables to use thermal-zone on DT if it was calles as
"renesas,rcar-thermal-gen2".
Previous style (= non thermal-zone) is still supported by
"renesas,rcar-thermal" to keep compatibility for "git bisect".
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>

Documentation/devicetree/bindings/thermal/rcar-thermal.txt

 * Renesas R-Car Thermal
 
 Required properties:
-- compatible		: "renesas,thermal-<soctype>", "renesas,rcar-thermal"
-			  as fallback.
+- compatible		: "renesas,thermal-<soctype>",
+			   "renesas,rcar-gen2-thermal" (with thermal-zone) or
+			   "renesas,rcar-thermal" (without thermal-zone) as fallback.
 			  Examples with soctypes are:
 			    - "renesas,thermal-r8a73a4" (R-Mobile APE6)
 			    - "renesas,thermal-r8a7779" (R-Car H1)
@@ -36,3 +37,35 @@ thermal@e61f0000 {
 		0xe61f0300 0x38>;
 	interrupts = <0 69 IRQ_TYPE_LEVEL_HIGH>;
 };
+
+Example (with thermal-zone):
+
+thermal-zones {
+	cpu_thermal: cpu-thermal {
+		polling-delay-passive	= <1000>;
+		polling-delay		= <5000>;
+
+		thermal-sensors = <&thermal>;
+
+		trips {
+			cpu-crit {
+				temperature	= <115000>;
+				hysteresis	= <0>;
+				type		= "critical";
+			};
+		};
+		cooling-maps {
+		};
+	};
+};
+
+thermal: thermal@e61f0000 {
+	compatible =	"renesas,thermal-r8a7790",
+			"renesas,rcar-gen2-thermal",
+			"renesas,rcar-thermal";
+	reg = <0 0xe61f0000 0 0x14>, <0 0xe61f0100 0 0x38>;
+	interrupts = <0 69 IRQ_TYPE_LEVEL_HIGH>;
+	clocks = <&mstp5_clks R8A7790_CLK_THERMAL>;
+	power-domains = <&cpg_clocks>;
+	#thermal-sensor-cells = <0>;
+};

drivers/thermal/rcar_thermal.c

@@ -23,6 +23,7 @@
 #include <linux/interrupt.h>
 #include <linux/io.h>
 #include <linux/module.h>
+#include <linux/of_device.h>
 #include <linux/platform_device.h>
 #include <linux/pm_runtime.h>
 #include <linux/reboot.h>
@@ -75,8 +76,10 @@ struct rcar_thermal_priv {
 #define rcar_has_irq_support(priv)	((priv)->common->base)
 #define rcar_id_to_shift(priv)		((priv)->id * 8)
 
+#define USE_OF_THERMAL	1
 static const struct of_device_id rcar_thermal_dt_ids[] = {
 	{ .compatible = "renesas,rcar-thermal", },
+	{ .compatible = "renesas,rcar-gen2-thermal", .data = (void *)USE_OF_THERMAL },
 	{},
 };
 MODULE_DEVICE_TABLE(of, rcar_thermal_dt_ids);
@@ -200,9 +203,9 @@ static int rcar_thermal_update_temp(struct rcar_thermal_priv *priv)
 	return ret;
 }
 
-static int rcar_thermal_get_temp(struct thermal_zone_device *zone, int *temp)
+static int rcar_thermal_get_current_temp(struct rcar_thermal_priv *priv,
+					 int *temp)
 {
-	struct rcar_thermal_priv *priv = rcar_zone_to_priv(zone);
 	int tmp;
 	int ret;
 
@@ -226,6 +229,20 @@ static int rcar_thermal_get_temp(struct thermal_zone_device *zone, int *temp)
 	return 0;
 }
 
+static int rcar_thermal_of_get_temp(void *data, int *temp)
+{
+	struct rcar_thermal_priv *priv = data;
+
+	return rcar_thermal_get_current_temp(priv, temp);
+}
+
+static int rcar_thermal_get_temp(struct thermal_zone_device *zone, int *temp)
+{
+	struct rcar_thermal_priv *priv = rcar_zone_to_priv(zone);
+
+	return rcar_thermal_get_current_temp(priv, temp);
+}
+
 static int rcar_thermal_get_trip_type(struct thermal_zone_device *zone,
 				      int trip, enum thermal_trip_type *type)
 {
@@ -282,6 +299,10 @@ static int rcar_thermal_notify(struct thermal_zone_device *zone,
 	return 0;
 }
 
+static const struct thermal_zone_of_device_ops rcar_thermal_zone_of_ops = {
+	.get_temp	= rcar_thermal_of_get_temp,
+};
+
 static struct thermal_zone_device_ops rcar_thermal_zone_ops = {
 	.get_temp	= rcar_thermal_get_temp,
 	.get_trip_type	= rcar_thermal_get_trip_type,
@@ -318,14 +339,20 @@ static void rcar_thermal_work(struct work_struct *work)
 
 	priv = container_of(work, struct rcar_thermal_priv, work.work);
 
-	rcar_thermal_get_temp(priv->zone, &cctemp);
+	ret = rcar_thermal_get_current_temp(priv, &cctemp);
+	if (ret < 0)
+		return;
+
 	ret = rcar_thermal_update_temp(priv);
 	if (ret < 0)
 		return;
 
 	rcar_thermal_irq_enable(priv);
 
-	rcar_thermal_get_temp(priv->zone, &nctemp);
+	ret = rcar_thermal_get_current_temp(priv, &nctemp);
+	if (ret < 0)
+		return;
+
 	if (nctemp != cctemp)
 		thermal_zone_device_update(priv->zone);
 }
@@ -403,6 +430,8 @@ static int rcar_thermal_probe(struct platform_device *pdev)
 	struct rcar_thermal_priv *priv;
 	struct device *dev = &pdev->dev;
 	struct resource *res, *irq;
+	const struct of_device_id *of_id = of_match_device(rcar_thermal_dt_ids, dev);
+	unsigned long of_data = (unsigned long)of_id->data;
 	int mres = 0;
 	int i;
 	int ret = -ENODEV;
@@ -463,7 +492,13 @@ static int rcar_thermal_probe(struct platform_device *pdev)
 		if (ret < 0)
 			goto error_unregister;
 
-		priv->zone = thermal_zone_device_register("rcar_thermal",
+		if (of_data == USE_OF_THERMAL)
+			priv->zone = thermal_zone_of_sensor_register(
+						dev, i, priv,
+						&rcar_thermal_zone_of_ops);
+		else
+			priv->zone = thermal_zone_device_register(
+						"rcar_thermal",
 						1, 0, priv,
 						&rcar_thermal_zone_ops, NULL, 0,
 						idle);