This patch adds a policy sysfs attribute to a thermal zone.
This attribute will give us the throttling policy used
for the zone. This is a RO attribute.

Signed-off-by: Durgadoss R <redacted>
---
 drivers/thermal/thermal_sys.c |   40 ++++++++++++++++++++++++++++++++++++++++
 include/linux/thermal.h       |    1 +
 2 files changed, 41 insertions(+)

diff --git a/drivers/thermal/thermal_sys.c b/drivers/thermal/thermal_sys.c
index 243a3f0..195e529 100644
--- a/drivers/thermal/thermal_sys.c
+++ b/drivers/thermal/thermal_sys.c

@@ -411,6 +411,27 @@ passive_show(struct device *dev, struct device_attribute *attr,
 	return sprintf(buf, "%d\n", tz->forced_passive);
 }
 
+static ssize_t show_throttle_policy(struct device *dev,
+			struct device_attribute *devattr, char *buf)
+{
+	struct thermal_zone_device *tz = to_thermal_zone(dev);
+	struct thermal_zone_params *tzp = tz->tzp;
+
+	if (!tzp)
+		return sprintf(buf, "step_wise(default)\n");
+
+	switch (tzp->throttle_policy) {
+	case THERMAL_FAIR_SHARE:
+		return sprintf(buf, "fair_share\n");
+	case THERMAL_STEP_WISE:
+		return sprintf(buf, "step_wise\n");
+	case THERMAL_USER_SPACE:
+		return sprintf(buf, "user_space\n");
+	default:
+		return sprintf(buf, "unknown\n");
+	}

+}
+
 static DEVICE_ATTR(type, 0444, type_show, NULL);
 static DEVICE_ATTR(temp, 0444, temp_show, NULL);
 static DEVICE_ATTR(mode, 0644, mode_show, mode_store);

@@ -1269,6 +1290,15 @@ leave:
 }
 EXPORT_SYMBOL(thermal_zone_device_update);
 
+static int create_policy_attr(struct thermal_zone_device *tz)
+{
+	sysfs_attr_init(&tz->policy_attr.attr);
+	tz->policy_attr.attr.name = "throttle_policy";
+	tz->policy_attr.attr.mode = S_IRUGO | S_IWUSR;
+	tz->policy_attr.show = show_throttle_policy;
+	return device_create_file(&tz->device, &tz->policy_attr);
+}
+
 /**
  * create_trip_attrs - create attributes for trip points
  * @tz:		the thermal zone device

@@ -1479,6 +1509,14 @@ struct thermal_zone_device *thermal_zone_device_register(const char *type,
 	/* Retrieve platform level parameters for this zone */
 	retrieve_zone_params(tz);
 
+	result = create_policy_attr(tz);
+	if (result) {
+		dev_err(&tz->device,
+			"create_policy_attr for zone %s failed:%d\n",
+			tz->type, result);
+		goto unregister;
+	}
+
 	mutex_lock(&thermal_list_lock);
 	list_add_tail(&tz->node, &thermal_tz_list);
 	if (ops->bind)

@@ -1539,6 +1577,8 @@ void thermal_zone_device_unregister(struct thermal_zone_device *tz)
 		device_remove_file(&tz->device, &dev_attr_mode);
 	remove_trip_attrs(tz);
 
+	device_remove_file(&tz->device, &tz->policy_attr);
+
 	thermal_remove_hwmon_sysfs(tz);
 	release_idr(&thermal_tz_idr, &thermal_idr_lock, tz->id);
 	idr_destroy(&tz->idr);

diff --git a/include/linux/thermal.h b/include/linux/thermal.h
index f9ce1e2..1d49f05 100644
--- a/include/linux/thermal.h
+++ b/include/linux/thermal.h

@@ -173,6 +173,7 @@ struct thermal_zone_device {
 	struct list_head node;
 	struct delayed_work poll_queue;
 	struct thermal_zone_params *tzp;
+	struct device_attribute policy_attr;
 };
 
 /*

-- 
1.7.9.5