[PATCH v1 2/2] thermal: qoriq: Add device cooling support

[Alice Guo (OSS)]

From: Anson Huang <Anson.Huang@xxxxxxx>

Register device cooling for first thermal zone manually, when
temperature exceeds passive trip, system wide cooling notification
will be triggered.

Signed-off-by: Anson Huang <Anson.Huang@xxxxxxx>
Signed-off-by: Alice Guo <alice.guo@xxxxxxx>
Reviewed-by: Jacky Bai <ping.bai@xxxxxxx>
---
 drivers/thermal/qoriq_thermal.c | 83 ++++++++++++++++++++++++++++++++-
 1 file changed, 82 insertions(+), 1 deletion(-)

diff --git a/drivers/thermal/qoriq_thermal.c b/drivers/thermal/qoriq_thermal.c
index d111e218f362..3c21b2d184eb 100644
--- a/drivers/thermal/qoriq_thermal.c
+++ b/drivers/thermal/qoriq_thermal.c
@@ -3,6 +3,7 @@
 // Copyright 2016 Freescale Semiconductor, Inc.
 
 #include <linux/clk.h>
+#include <linux/device_cooling.h>
 #include <linux/err.h>
 #include <linux/io.h>
 #include <linux/module.h>
@@ -27,6 +28,7 @@
 #define TMSARA_V2		0xe
 #define TMU_VER1		0x1
 #define TMU_VER2		0x2
+#define TMU_TEMP_PASSIVE_COOL_DELTA	10000
 
 #define REGS_TMR	0x000	/* Mode Register */
 #define TMR_DISABLE	0x0
@@ -68,6 +70,10 @@
  */
 struct qoriq_sensor {
 	int				id;
+	struct thermal_zone_device	*tzd;
+	int				temp_passive;
+	int				temp_critical;
+	struct thermal_cooling_device	*cdev;
 };
 
 struct qoriq_tmu_data {
@@ -77,6 +83,12 @@ struct qoriq_tmu_data {
 	struct qoriq_sensor	sensor[SITES_MAX];
 };
 
+enum tmu_trip {
+	TMU_TRIP_PASSIVE,
+	TMU_TRIP_CRITICAL,
+	TMU_TRIP_NUM,
+};
+
 static struct qoriq_tmu_data *qoriq_sensor_to_data(struct qoriq_sensor *s)
 {
 	return container_of(s, struct qoriq_tmu_data, sensor[s->id]);
@@ -122,14 +134,53 @@ static int tmu_get_temp(struct thermal_zone_device *tz, int *temp)
 	return 0;
 }
 
+static int tmu_get_trend(struct thermal_zone_device *tz, int trip,
+				    enum thermal_trend *trend)
+
+{
+	struct qoriq_sensor *qsensor = tz->devdata;
+	int trip_temp;
+
+	if (!qsensor->tzd)
+		return 0;
+
+	trip_temp = (trip == TMU_TRIP_PASSIVE) ? qsensor->temp_passive :
+					     qsensor->temp_critical;
+
+	if (qsensor->tzd->temperature >=
+		(trip_temp - TMU_TEMP_PASSIVE_COOL_DELTA))
+		*trend = THERMAL_TREND_RAISING;
+	else
+		*trend = THERMAL_TREND_DROPPING;
+
+	return 0;
+}
+
+static int tmu_set_trip_temp(struct thermal_zone_device *tz, int trip,
+			     int temp)
+{
+	struct qoriq_sensor *qsensor = tz->devdata;
+
+	if (trip == TMU_TRIP_CRITICAL)
+		qsensor->temp_critical = temp;
+
+	if (trip == TMU_TRIP_PASSIVE)
+		qsensor->temp_passive = temp;
+
+	return 0;
+}
+
 static const struct thermal_zone_device_ops tmu_tz_ops = {
 	.get_temp = tmu_get_temp,
+	.get_trend = tmu_get_trend,
+	.set_trip_temp = tmu_set_trip_temp,
 };
 
 static int qoriq_tmu_register_tmu_zone(struct device *dev,
 				       struct qoriq_tmu_data *qdata)
 {
 	int id;
+	const struct thermal_trip *trip;
 
 	if (qdata->ver == TMU_VER1) {
 		regmap_write(qdata->regmap, REGS_TMR,
@@ -158,10 +209,40 @@ static int qoriq_tmu_register_tmu_zone(struct device *dev,
 			return ret;
 		}
 
+		sensor->tzd = tzd;
+
 		if (devm_thermal_add_hwmon_sysfs(tzd))
 			dev_warn(dev,
 				 "Failed to add hwmon sysfs attributes\n");
-
+		/* first thermal zone takes care of system-wide device cooling */
+		if (id == 0) {
+			sensor->cdev = devfreq_cooling_register();
+			if (IS_ERR(sensor->cdev)) {
+				ret = PTR_ERR(sensor->cdev);
+				pr_err("failed to register devfreq cooling device: %d\n",
+					ret);
+				return ret;
+			}
+
+			ret = thermal_zone_bind_cooling_device(sensor->tzd,
+				TMU_TRIP_PASSIVE,
+				sensor->cdev,
+				THERMAL_NO_LIMIT,
+				THERMAL_NO_LIMIT,
+				THERMAL_WEIGHT_DEFAULT);
+			if (ret) {
+				pr_err("binding zone %s with cdev %s failed:%d\n",
+					sensor->tzd->type,
+					sensor->cdev->type,
+					ret);
+				devfreq_cooling_unregister(sensor->cdev);
+				return ret;
+			}
+
+			trip = of_thermal_get_trip_points(sensor->tzd);
+			sensor->temp_passive = trip[0].temperature;
+			sensor->temp_critical = trip[1].temperature;
+		}
 	}
 
 	return 0;
-- 
2.17.1