Adding upstream version 4.19.249.upstream/4.19.249upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1007 insertions, 0 deletions

diff --git a/drivers/thermal/thermal_sysfs.c b/drivers/thermal/thermal_sysfs.c
new file mode 100644
index 000000000..4dce4a8f7
--- /dev/null
+++ b/drivers/thermal/thermal_sysfs.c
@@ -0,0 +1,1007 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *  thermal.c - sysfs interface of thermal devices
+ *
+ *  Copyright (C) 2016 Eduardo Valentin <edubezval@gmail.com>
+ *
+ *  Highly based on original thermal_core.c
+ *  Copyright (C) 2008 Intel Corp
+ *  Copyright (C) 2008 Zhang Rui <rui.zhang@intel.com>
+ *  Copyright (C) 2008 Sujith Thomas <sujith.thomas@intel.com>
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/sysfs.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/jiffies.h>
+
+#include "thermal_core.h"
+
+/* sys I/F for thermal zone */
+
+static ssize_t
+type_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct thermal_zone_device *tz = to_thermal_zone(dev);
+
+	return sprintf(buf, "%s\n", tz->type);
+}
+
+static ssize_t
+temp_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct thermal_zone_device *tz = to_thermal_zone(dev);
+	int temperature, ret;
+
+	ret = thermal_zone_get_temp(tz, &temperature);
+
+	if (ret)
+		return ret;
+
+	return sprintf(buf, "%d\n", temperature);
+}
+
+static ssize_t
+mode_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct thermal_zone_device *tz = to_thermal_zone(dev);
+	enum thermal_device_mode mode;
+	int result;
+
+	if (!tz->ops->get_mode)
+		return -EPERM;
+
+	result = tz->ops->get_mode(tz, &mode);
+	if (result)
+		return result;
+
+	return sprintf(buf, "%s\n", mode == THERMAL_DEVICE_ENABLED ? "enabled"
+		       : "disabled");
+}
+
+static ssize_t
+mode_store(struct device *dev, struct device_attribute *attr,
+	   const char *buf, size_t count)
+{
+	struct thermal_zone_device *tz = to_thermal_zone(dev);
+	int result;
+
+	if (!tz->ops->set_mode)
+		return -EPERM;
+
+	if (!strncmp(buf, "enabled", sizeof("enabled") - 1))
+		result = tz->ops->set_mode(tz, THERMAL_DEVICE_ENABLED);
+	else if (!strncmp(buf, "disabled", sizeof("disabled") - 1))
+		result = tz->ops->set_mode(tz, THERMAL_DEVICE_DISABLED);
+	else
+		result = -EINVAL;
+
+	if (result)
+		return result;
+
+	return count;
+}
+
+static ssize_t
+trip_point_type_show(struct device *dev, struct device_attribute *attr,
+		     char *buf)
+{
+	struct thermal_zone_device *tz = to_thermal_zone(dev);
+	enum thermal_trip_type type;
+	int trip, result;
+
+	if (!tz->ops->get_trip_type)
+		return -EPERM;
+
+	if (sscanf(attr->attr.name, "trip_point_%d_type", &trip) != 1)
+		return -EINVAL;
+
+	result = tz->ops->get_trip_type(tz, trip, &type);
+	if (result)
+		return result;
+
+	switch (type) {
+	case THERMAL_TRIP_CRITICAL:
+		return sprintf(buf, "critical\n");
+	case THERMAL_TRIP_HOT:
+		return sprintf(buf, "hot\n");
+	case THERMAL_TRIP_PASSIVE:
+		return sprintf(buf, "passive\n");
+	case THERMAL_TRIP_ACTIVE:
+		return sprintf(buf, "active\n");
+	default:
+		return sprintf(buf, "unknown\n");
+	}
+}
+
+static ssize_t
+trip_point_temp_store(struct device *dev, struct device_attribute *attr,
+		      const char *buf, size_t count)
+{
+	struct thermal_zone_device *tz = to_thermal_zone(dev);
+	int trip, ret;
+	int temperature;
+
+	if (!tz->ops->set_trip_temp)
+		return -EPERM;
+
+	if (sscanf(attr->attr.name, "trip_point_%d_temp", &trip) != 1)
+		return -EINVAL;
+
+	if (kstrtoint(buf, 10, &temperature))
+		return -EINVAL;
+
+	ret = tz->ops->set_trip_temp(tz, trip, temperature);
+	if (ret)
+		return ret;
+
+	thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
+
+	return count;
+}
+
+static ssize_t
+trip_point_temp_show(struct device *dev, struct device_attribute *attr,
+		     char *buf)
+{
+	struct thermal_zone_device *tz = to_thermal_zone(dev);
+	int trip, ret;
+	int temperature;
+
+	if (!tz->ops->get_trip_temp)
+		return -EPERM;
+
+	if (sscanf(attr->attr.name, "trip_point_%d_temp", &trip) != 1)
+		return -EINVAL;
+
+	ret = tz->ops->get_trip_temp(tz, trip, &temperature);
+
+	if (ret)
+		return ret;
+
+	return sprintf(buf, "%d\n", temperature);
+}
+
+static ssize_t
+trip_point_hyst_store(struct device *dev, struct device_attribute *attr,
+		      const char *buf, size_t count)
+{
+	struct thermal_zone_device *tz = to_thermal_zone(dev);
+	int trip, ret;
+	int temperature;
+
+	if (!tz->ops->set_trip_hyst)
+		return -EPERM;
+
+	if (sscanf(attr->attr.name, "trip_point_%d_hyst", &trip) != 1)
+		return -EINVAL;
+
+	if (kstrtoint(buf, 10, &temperature))
+		return -EINVAL;
+
+	/*
+	 * We are not doing any check on the 'temperature' value
+	 * here. The driver implementing 'set_trip_hyst' has to
+	 * take care of this.
+	 */
+	ret = tz->ops->set_trip_hyst(tz, trip, temperature);
+
+	if (!ret)
+		thermal_zone_set_trips(tz);
+
+	return ret ? ret : count;
+}
+
+static ssize_t
+trip_point_hyst_show(struct device *dev, struct device_attribute *attr,
+		     char *buf)
+{
+	struct thermal_zone_device *tz = to_thermal_zone(dev);
+	int trip, ret;
+	int temperature;
+
+	if (!tz->ops->get_trip_hyst)
+		return -EPERM;
+
+	if (sscanf(attr->attr.name, "trip_point_%d_hyst", &trip) != 1)
+		return -EINVAL;
+
+	ret = tz->ops->get_trip_hyst(tz, trip, &temperature);
+
+	return ret ? ret : sprintf(buf, "%d\n", temperature);
+}
+
+static ssize_t
+passive_store(struct device *dev, struct device_attribute *attr,
+	      const char *buf, size_t count)
+{
+	struct thermal_zone_device *tz = to_thermal_zone(dev);
+	int state;
+
+	if (sscanf(buf, "%d\n", &state) != 1)
+		return -EINVAL;
+
+	/* sanity check: values below 1000 millicelcius don't make sense
+	 * and can cause the system to go into a thermal heart attack
+	 */
+	if (state && state < 1000)
+		return -EINVAL;
+
+	if (state && !tz->forced_passive) {
+		if (!tz->passive_delay)
+			tz->passive_delay = 1000;
+		thermal_zone_device_rebind_exception(tz, "Processor",
+						     sizeof("Processor"));
+	} else if (!state && tz->forced_passive) {
+		tz->passive_delay = 0;
+		thermal_zone_device_unbind_exception(tz, "Processor",
+						     sizeof("Processor"));
+	}
+
+	tz->forced_passive = state;
+
+	thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
+
+	return count;
+}
+
+static ssize_t
+passive_show(struct device *dev, struct device_attribute *attr,
+	     char *buf)
+{
+	struct thermal_zone_device *tz = to_thermal_zone(dev);
+
+	return sprintf(buf, "%d\n", tz->forced_passive);
+}
+
+static ssize_t
+policy_store(struct device *dev, struct device_attribute *attr,
+	     const char *buf, size_t count)
+{
+	struct thermal_zone_device *tz = to_thermal_zone(dev);
+	char name[THERMAL_NAME_LENGTH];
+	int ret;
+
+	snprintf(name, sizeof(name), "%s", buf);
+
+	ret = thermal_zone_device_set_policy(tz, name);
+	if (!ret)
+		ret = count;
+
+	return ret;
+}
+
+static ssize_t
+policy_show(struct device *dev, struct device_attribute *devattr, char *buf)
+{
+	struct thermal_zone_device *tz = to_thermal_zone(dev);
+
+	return sprintf(buf, "%s\n", tz->governor->name);
+}
+
+static ssize_t
+available_policies_show(struct device *dev, struct device_attribute *devattr,
+			char *buf)
+{
+	return thermal_build_list_of_policies(buf);
+}
+
+#if (IS_ENABLED(CONFIG_THERMAL_EMULATION))
+static ssize_t
+emul_temp_store(struct device *dev, struct device_attribute *attr,
+		const char *buf, size_t count)
+{
+	struct thermal_zone_device *tz = to_thermal_zone(dev);
+	int ret = 0;
+	int temperature;
+
+	if (kstrtoint(buf, 10, &temperature))
+		return -EINVAL;
+
+	if (!tz->ops->set_emul_temp) {
+		mutex_lock(&tz->lock);
+		tz->emul_temperature = temperature;
+		mutex_unlock(&tz->lock);
+	} else {
+		ret = tz->ops->set_emul_temp(tz, temperature);
+	}
+
+	if (!ret)
+		thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
+
+	return ret ? ret : count;
+}
+static DEVICE_ATTR_WO(emul_temp);
+#endif
+
+static ssize_t
+sustainable_power_show(struct device *dev, struct device_attribute *devattr,
+		       char *buf)
+{
+	struct thermal_zone_device *tz = to_thermal_zone(dev);
+
+	if (tz->tzp)
+		return sprintf(buf, "%u\n", tz->tzp->sustainable_power);
+	else
+		return -EIO;
+}
+
+static ssize_t
+sustainable_power_store(struct device *dev, struct device_attribute *devattr,
+			const char *buf, size_t count)
+{
+	struct thermal_zone_device *tz = to_thermal_zone(dev);
+	u32 sustainable_power;
+
+	if (!tz->tzp)
+		return -EIO;
+
+	if (kstrtou32(buf, 10, &sustainable_power))
+		return -EINVAL;
+
+	tz->tzp->sustainable_power = sustainable_power;
+
+	return count;
+}
+
+#define create_s32_tzp_attr(name)					\
+	static ssize_t							\
+	name##_show(struct device *dev, struct device_attribute *devattr, \
+		char *buf)						\
+	{								\
+	struct thermal_zone_device *tz = to_thermal_zone(dev);		\
+									\
+	if (tz->tzp)							\
+		return sprintf(buf, "%d\n", tz->tzp->name);		\
+	else								\
+		return -EIO;						\
+	}								\
+									\
+	static ssize_t							\
+	name##_store(struct device *dev, struct device_attribute *devattr, \
+		const char *buf, size_t count)				\
+	{								\
+		struct thermal_zone_device *tz = to_thermal_zone(dev);	\
+		s32 value;						\
+									\
+		if (!tz->tzp)						\
+			return -EIO;					\
+									\
+		if (kstrtos32(buf, 10, &value))				\
+			return -EINVAL;					\
+									\
+		tz->tzp->name = value;					\
+									\
+		return count;						\
+	}								\
+	static DEVICE_ATTR_RW(name)
+
+create_s32_tzp_attr(k_po);
+create_s32_tzp_attr(k_pu);
+create_s32_tzp_attr(k_i);
+create_s32_tzp_attr(k_d);
+create_s32_tzp_attr(integral_cutoff);
+create_s32_tzp_attr(slope);
+create_s32_tzp_attr(offset);
+#undef create_s32_tzp_attr
+
+/*
+ * These are thermal zone device attributes that will always be present.
+ * All the attributes created for tzp (create_s32_tzp_attr) also are always
+ * present on the sysfs interface.
+ */
+static DEVICE_ATTR_RO(type);
+static DEVICE_ATTR_RO(temp);
+static DEVICE_ATTR_RW(policy);
+static DEVICE_ATTR_RO(available_policies);
+static DEVICE_ATTR_RW(sustainable_power);
+
+/* These thermal zone device attributes are created based on conditions */
+static DEVICE_ATTR_RW(mode);
+static DEVICE_ATTR_RW(passive);
+
+/* These attributes are unconditionally added to a thermal zone */
+static struct attribute *thermal_zone_dev_attrs[] = {
+	&dev_attr_type.attr,
+	&dev_attr_temp.attr,
+#if (IS_ENABLED(CONFIG_THERMAL_EMULATION))
+	&dev_attr_emul_temp.attr,
+#endif
+	&dev_attr_policy.attr,
+	&dev_attr_available_policies.attr,
+	&dev_attr_sustainable_power.attr,
+	&dev_attr_k_po.attr,
+	&dev_attr_k_pu.attr,
+	&dev_attr_k_i.attr,
+	&dev_attr_k_d.attr,
+	&dev_attr_integral_cutoff.attr,
+	&dev_attr_slope.attr,
+	&dev_attr_offset.attr,
+	NULL,
+};
+
+static struct attribute_group thermal_zone_attribute_group = {
+	.attrs = thermal_zone_dev_attrs,
+};
+
+/* We expose mode only if .get_mode is present */
+static struct attribute *thermal_zone_mode_attrs[] = {
+	&dev_attr_mode.attr,
+	NULL,
+};
+
+static umode_t thermal_zone_mode_is_visible(struct kobject *kobj,
+					    struct attribute *attr,
+					    int attrno)
+{
+	struct device *dev = container_of(kobj, struct device, kobj);
+	struct thermal_zone_device *tz;
+
+	tz = container_of(dev, struct thermal_zone_device, device);
+
+	if (tz->ops->get_mode)
+		return attr->mode;
+
+	return 0;
+}
+
+static struct attribute_group thermal_zone_mode_attribute_group = {
+	.attrs = thermal_zone_mode_attrs,
+	.is_visible = thermal_zone_mode_is_visible,
+};
+
+/* We expose passive only if passive trips are present */
+static struct attribute *thermal_zone_passive_attrs[] = {
+	&dev_attr_passive.attr,
+	NULL,
+};
+
+static umode_t thermal_zone_passive_is_visible(struct kobject *kobj,
+					       struct attribute *attr,
+					       int attrno)
+{
+	struct device *dev = container_of(kobj, struct device, kobj);
+	struct thermal_zone_device *tz;
+	enum thermal_trip_type trip_type;
+	int count, passive = 0;
+
+	tz = container_of(dev, struct thermal_zone_device, device);
+
+	for (count = 0; count < tz->trips && !passive; count++) {
+		tz->ops->get_trip_type(tz, count, &trip_type);
+
+		if (trip_type == THERMAL_TRIP_PASSIVE)
+			passive = 1;
+	}
+
+	if (!passive)
+		return attr->mode;
+
+	return 0;
+}
+
+static struct attribute_group thermal_zone_passive_attribute_group = {
+	.attrs = thermal_zone_passive_attrs,
+	.is_visible = thermal_zone_passive_is_visible,
+};
+
+static const struct attribute_group *thermal_zone_attribute_groups[] = {
+	&thermal_zone_attribute_group,
+	&thermal_zone_mode_attribute_group,
+	&thermal_zone_passive_attribute_group,
+	/* This is not NULL terminated as we create the group dynamically */
+};
+
+/**
+ * create_trip_attrs() - create attributes for trip points
+ * @tz:		the thermal zone device
+ * @mask:	Writeable trip point bitmap.
+ *
+ * helper function to instantiate sysfs entries for every trip
+ * point and its properties of a struct thermal_zone_device.
+ *
+ * Return: 0 on success, the proper error value otherwise.
+ */
+static int create_trip_attrs(struct thermal_zone_device *tz, int mask)
+{
+	struct attribute **attrs;
+	int indx;
+
+	/* This function works only for zones with at least one trip */
+	if (tz->trips <= 0)
+		return -EINVAL;
+
+	tz->trip_type_attrs = kcalloc(tz->trips, sizeof(*tz->trip_type_attrs),
+				      GFP_KERNEL);
+	if (!tz->trip_type_attrs)
+		return -ENOMEM;
+
+	tz->trip_temp_attrs = kcalloc(tz->trips, sizeof(*tz->trip_temp_attrs),
+				      GFP_KERNEL);
+	if (!tz->trip_temp_attrs) {
+		kfree(tz->trip_type_attrs);
+		return -ENOMEM;
+	}
+
+	if (tz->ops->get_trip_hyst) {
+		tz->trip_hyst_attrs = kcalloc(tz->trips,
+					      sizeof(*tz->trip_hyst_attrs),
+					      GFP_KERNEL);
+		if (!tz->trip_hyst_attrs) {
+			kfree(tz->trip_type_attrs);
+			kfree(tz->trip_temp_attrs);
+			return -ENOMEM;
+		}
+	}
+
+	attrs = kcalloc(tz->trips * 3 + 1, sizeof(*attrs), GFP_KERNEL);
+	if (!attrs) {
+		kfree(tz->trip_type_attrs);
+		kfree(tz->trip_temp_attrs);
+		if (tz->ops->get_trip_hyst)
+			kfree(tz->trip_hyst_attrs);
+		return -ENOMEM;
+	}
+
+	for (indx = 0; indx < tz->trips; indx++) {
+		/* create trip type attribute */
+		snprintf(tz->trip_type_attrs[indx].name, THERMAL_NAME_LENGTH,
+			 "trip_point_%d_type", indx);
+
+		sysfs_attr_init(&tz->trip_type_attrs[indx].attr.attr);
+		tz->trip_type_attrs[indx].attr.attr.name =
+						tz->trip_type_attrs[indx].name;
+		tz->trip_type_attrs[indx].attr.attr.mode = S_IRUGO;
+		tz->trip_type_attrs[indx].attr.show = trip_point_type_show;
+		attrs[indx] = &tz->trip_type_attrs[indx].attr.attr;
+
+		/* create trip temp attribute */
+		snprintf(tz->trip_temp_attrs[indx].name, THERMAL_NAME_LENGTH,
+			 "trip_point_%d_temp", indx);
+
+		sysfs_attr_init(&tz->trip_temp_attrs[indx].attr.attr);
+		tz->trip_temp_attrs[indx].attr.attr.name =
+						tz->trip_temp_attrs[indx].name;
+		tz->trip_temp_attrs[indx].attr.attr.mode = S_IRUGO;
+		tz->trip_temp_attrs[indx].attr.show = trip_point_temp_show;
+		if (IS_ENABLED(CONFIG_THERMAL_WRITABLE_TRIPS) &&
+		    mask & (1 << indx)) {
+			tz->trip_temp_attrs[indx].attr.attr.mode |= S_IWUSR;
+			tz->trip_temp_attrs[indx].attr.store =
+							trip_point_temp_store;
+		}
+		attrs[indx + tz->trips] = &tz->trip_temp_attrs[indx].attr.attr;
+
+		/* create Optional trip hyst attribute */
+		if (!tz->ops->get_trip_hyst)
+			continue;
+		snprintf(tz->trip_hyst_attrs[indx].name, THERMAL_NAME_LENGTH,
+			 "trip_point_%d_hyst", indx);
+
+		sysfs_attr_init(&tz->trip_hyst_attrs[indx].attr.attr);
+		tz->trip_hyst_attrs[indx].attr.attr.name =
+					tz->trip_hyst_attrs[indx].name;
+		tz->trip_hyst_attrs[indx].attr.attr.mode = S_IRUGO;
+		tz->trip_hyst_attrs[indx].attr.show = trip_point_hyst_show;
+		if (tz->ops->set_trip_hyst) {
+			tz->trip_hyst_attrs[indx].attr.attr.mode |= S_IWUSR;
+			tz->trip_hyst_attrs[indx].attr.store =
+					trip_point_hyst_store;
+		}
+		attrs[indx + tz->trips * 2] =
+					&tz->trip_hyst_attrs[indx].attr.attr;
+	}
+	attrs[tz->trips * 3] = NULL;
+
+	tz->trips_attribute_group.attrs = attrs;
+
+	return 0;
+}
+
+/**
+ * destroy_trip_attrs() - destroy attributes for trip points
+ * @tz:		the thermal zone device
+ *
+ * helper function to free resources allocated by create_trip_attrs()
+ */
+static void destroy_trip_attrs(struct thermal_zone_device *tz)
+{
+	if (!tz)
+		return;
+
+	kfree(tz->trip_type_attrs);
+	kfree(tz->trip_temp_attrs);
+	if (tz->ops->get_trip_hyst)
+		kfree(tz->trip_hyst_attrs);
+	kfree(tz->trips_attribute_group.attrs);
+}
+
+int thermal_zone_create_device_groups(struct thermal_zone_device *tz,
+				      int mask)
+{
+	const struct attribute_group **groups;
+	int i, size, result;
+
+	/* we need one extra for trips and the NULL to terminate the array */
+	size = ARRAY_SIZE(thermal_zone_attribute_groups) + 2;
+	/* This also takes care of API requirement to be NULL terminated */
+	groups = kcalloc(size, sizeof(*groups), GFP_KERNEL);
+	if (!groups)
+		return -ENOMEM;
+
+	for (i = 0; i < size - 2; i++)
+		groups[i] = thermal_zone_attribute_groups[i];
+
+	if (tz->trips) {
+		result = create_trip_attrs(tz, mask);
+		if (result) {
+			kfree(groups);
+
+			return result;
+		}
+
+		groups[size - 2] = &tz->trips_attribute_group;
+	}
+
+	tz->device.groups = groups;
+
+	return 0;
+}
+
+void thermal_zone_destroy_device_groups(struct thermal_zone_device *tz)
+{
+	if (!tz)
+		return;
+
+	if (tz->trips)
+		destroy_trip_attrs(tz);
+
+	kfree(tz->device.groups);
+}
+
+/* sys I/F for cooling device */
+static ssize_t
+cdev_type_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct thermal_cooling_device *cdev = to_cooling_device(dev);
+
+	return sprintf(buf, "%s\n", cdev->type);
+}
+
+static ssize_t max_state_show(struct device *dev, struct device_attribute *attr,
+			      char *buf)
+{
+	struct thermal_cooling_device *cdev = to_cooling_device(dev);
+	unsigned long state;
+	int ret;
+
+	ret = cdev->ops->get_max_state(cdev, &state);
+	if (ret)
+		return ret;
+	return sprintf(buf, "%ld\n", state);
+}
+
+static ssize_t cur_state_show(struct device *dev, struct device_attribute *attr,
+			      char *buf)
+{
+	struct thermal_cooling_device *cdev = to_cooling_device(dev);
+	unsigned long state;
+	int ret;
+
+	ret = cdev->ops->get_cur_state(cdev, &state);
+	if (ret)
+		return ret;
+	return sprintf(buf, "%ld\n", state);
+}
+
+static ssize_t
+cur_state_store(struct device *dev, struct device_attribute *attr,
+		const char *buf, size_t count)
+{
+	struct thermal_cooling_device *cdev = to_cooling_device(dev);
+	unsigned long state;
+	int result;
+
+	if (sscanf(buf, "%ld\n", &state) != 1)
+		return -EINVAL;
+
+	if ((long)state < 0)
+		return -EINVAL;
+
+	mutex_lock(&cdev->lock);
+
+	result = cdev->ops->set_cur_state(cdev, state);
+	if (!result)
+		thermal_cooling_device_stats_update(cdev, state);
+
+	mutex_unlock(&cdev->lock);
+	return result ? result : count;
+}
+
+static struct device_attribute
+dev_attr_cdev_type = __ATTR(type, 0444, cdev_type_show, NULL);
+static DEVICE_ATTR_RO(max_state);
+static DEVICE_ATTR_RW(cur_state);
+
+static struct attribute *cooling_device_attrs[] = {
+	&dev_attr_cdev_type.attr,
+	&dev_attr_max_state.attr,
+	&dev_attr_cur_state.attr,
+	NULL,
+};
+
+static const struct attribute_group cooling_device_attr_group = {
+	.attrs = cooling_device_attrs,
+};
+
+static const struct attribute_group *cooling_device_attr_groups[] = {
+	&cooling_device_attr_group,
+	NULL, /* Space allocated for cooling_device_stats_attr_group */
+	NULL,
+};
+
+#ifdef CONFIG_THERMAL_STATISTICS
+struct cooling_dev_stats {
+	spinlock_t lock;
+	unsigned int total_trans;
+	unsigned long state;
+	unsigned long max_states;
+	ktime_t last_time;
+	ktime_t *time_in_state;
+	unsigned int *trans_table;
+};
+
+static void update_time_in_state(struct cooling_dev_stats *stats)
+{
+	ktime_t now = ktime_get(), delta;
+
+	delta = ktime_sub(now, stats->last_time);
+	stats->time_in_state[stats->state] =
+		ktime_add(stats->time_in_state[stats->state], delta);
+	stats->last_time = now;
+}
+
+void thermal_cooling_device_stats_update(struct thermal_cooling_device *cdev,
+					 unsigned long new_state)
+{
+	struct cooling_dev_stats *stats = cdev->stats;
+
+	if (!stats)
+		return;
+
+	spin_lock(&stats->lock);
+
+	if (stats->state == new_state)
+		goto unlock;
+
+	update_time_in_state(stats);
+	stats->trans_table[stats->state * stats->max_states + new_state]++;
+	stats->state = new_state;
+	stats->total_trans++;
+
+unlock:
+	spin_unlock(&stats->lock);
+}
+
+static ssize_t total_trans_show(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	struct thermal_cooling_device *cdev = to_cooling_device(dev);
+	struct cooling_dev_stats *stats = cdev->stats;
+	int ret;
+
+	spin_lock(&stats->lock);
+	ret = sprintf(buf, "%u\n", stats->total_trans);
+	spin_unlock(&stats->lock);
+
+	return ret;
+}
+
+static ssize_t
+time_in_state_ms_show(struct device *dev, struct device_attribute *attr,
+		      char *buf)
+{
+	struct thermal_cooling_device *cdev = to_cooling_device(dev);
+	struct cooling_dev_stats *stats = cdev->stats;
+	ssize_t len = 0;
+	int i;
+
+	spin_lock(&stats->lock);
+	update_time_in_state(stats);
+
+	for (i = 0; i < stats->max_states; i++) {
+		len += sprintf(buf + len, "state%u\t%llu\n", i,
+			       ktime_to_ms(stats->time_in_state[i]));
+	}
+	spin_unlock(&stats->lock);
+
+	return len;
+}
+
+static ssize_t
+reset_store(struct device *dev, struct device_attribute *attr, const char *buf,
+	    size_t count)
+{
+	struct thermal_cooling_device *cdev = to_cooling_device(dev);
+	struct cooling_dev_stats *stats = cdev->stats;
+	int i, states = stats->max_states;
+
+	spin_lock(&stats->lock);
+
+	stats->total_trans = 0;
+	stats->last_time = ktime_get();
+	memset(stats->trans_table, 0,
+	       states * states * sizeof(*stats->trans_table));
+
+	for (i = 0; i < stats->max_states; i++)
+		stats->time_in_state[i] = ktime_set(0, 0);
+
+	spin_unlock(&stats->lock);
+
+	return count;
+}
+
+static ssize_t trans_table_show(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	struct thermal_cooling_device *cdev = to_cooling_device(dev);
+	struct cooling_dev_stats *stats = cdev->stats;
+	ssize_t len = 0;
+	int i, j;
+
+	len += snprintf(buf + len, PAGE_SIZE - len, " From  :    To\n");
+	len += snprintf(buf + len, PAGE_SIZE - len, "       : ");
+	for (i = 0; i < stats->max_states; i++) {
+		if (len >= PAGE_SIZE)
+			break;
+		len += snprintf(buf + len, PAGE_SIZE - len, "state%2u  ", i);
+	}
+	if (len >= PAGE_SIZE)
+		return PAGE_SIZE;
+
+	len += snprintf(buf + len, PAGE_SIZE - len, "\n");
+
+	for (i = 0; i < stats->max_states; i++) {
+		if (len >= PAGE_SIZE)
+			break;
+
+		len += snprintf(buf + len, PAGE_SIZE - len, "state%2u:", i);
+
+		for (j = 0; j < stats->max_states; j++) {
+			if (len >= PAGE_SIZE)
+				break;
+			len += snprintf(buf + len, PAGE_SIZE - len, "%8u ",
+				stats->trans_table[i * stats->max_states + j]);
+		}
+		if (len >= PAGE_SIZE)
+			break;
+		len += snprintf(buf + len, PAGE_SIZE - len, "\n");
+	}
+
+	if (len >= PAGE_SIZE) {
+		pr_warn_once("Thermal transition table exceeds PAGE_SIZE. Disabling\n");
+		return -EFBIG;
+	}
+	return len;
+}
+
+static DEVICE_ATTR_RO(total_trans);
+static DEVICE_ATTR_RO(time_in_state_ms);
+static DEVICE_ATTR_WO(reset);
+static DEVICE_ATTR_RO(trans_table);
+
+static struct attribute *cooling_device_stats_attrs[] = {
+	&dev_attr_total_trans.attr,
+	&dev_attr_time_in_state_ms.attr,
+	&dev_attr_reset.attr,
+	&dev_attr_trans_table.attr,
+	NULL
+};
+
+static const struct attribute_group cooling_device_stats_attr_group = {
+	.attrs = cooling_device_stats_attrs,
+	.name = "stats"
+};
+
+static void cooling_device_stats_setup(struct thermal_cooling_device *cdev)
+{
+	struct cooling_dev_stats *stats;
+	unsigned long states;
+	int var;
+
+	if (cdev->ops->get_max_state(cdev, &states))
+		return;
+
+	states++; /* Total number of states is highest state + 1 */
+
+	var = sizeof(*stats);
+	var += sizeof(*stats->time_in_state) * states;
+	var += sizeof(*stats->trans_table) * states * states;
+
+	stats = kzalloc(var, GFP_KERNEL);
+	if (!stats)
+		return;
+
+	stats->time_in_state = (ktime_t *)(stats + 1);
+	stats->trans_table = (unsigned int *)(stats->time_in_state + states);
+	cdev->stats = stats;
+	stats->last_time = ktime_get();
+	stats->max_states = states;
+
+	spin_lock_init(&stats->lock);
+
+	/* Fill the empty slot left in cooling_device_attr_groups */
+	var = ARRAY_SIZE(cooling_device_attr_groups) - 2;
+	cooling_device_attr_groups[var] = &cooling_device_stats_attr_group;
+}
+
+static void cooling_device_stats_destroy(struct thermal_cooling_device *cdev)
+{
+	kfree(cdev->stats);
+	cdev->stats = NULL;
+}
+
+#else
+
+static inline void
+cooling_device_stats_setup(struct thermal_cooling_device *cdev) {}
+static inline void
+cooling_device_stats_destroy(struct thermal_cooling_device *cdev) {}
+
+#endif /* CONFIG_THERMAL_STATISTICS */
+
+void thermal_cooling_device_setup_sysfs(struct thermal_cooling_device *cdev)
+{
+	cooling_device_stats_setup(cdev);
+	cdev->device.groups = cooling_device_attr_groups;
+}
+
+void thermal_cooling_device_destroy_sysfs(struct thermal_cooling_device *cdev)
+{
+	cooling_device_stats_destroy(cdev);
+}
+
+/* these helper will be used only at the time of bindig */
+ssize_t
+trip_point_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct thermal_instance *instance;
+
+	instance =
+	    container_of(attr, struct thermal_instance, attr);
+
+	if (instance->trip == THERMAL_TRIPS_NONE)
+		return sprintf(buf, "-1\n");
+	else
+		return sprintf(buf, "%d\n", instance->trip);
+}
+
+ssize_t
+weight_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct thermal_instance *instance;
+
+	instance = container_of(attr, struct thermal_instance, weight_attr);
+
+	return sprintf(buf, "%d\n", instance->weight);
+}
+
+ssize_t weight_store(struct device *dev, struct device_attribute *attr,
+		     const char *buf, size_t count)
+{
+	struct thermal_instance *instance;
+	int ret, weight;
+
+	ret = kstrtoint(buf, 0, &weight);
+	if (ret)
+		return ret;
+
+	instance = container_of(attr, struct thermal_instance, weight_attr);
+	instance->weight = weight;
+
+	return count;
+}