Adding upstream version 6.6.15.upstream/6.6.15

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

1 files changed, 1156 insertions, 0 deletions

diff --git a/drivers/acpi/thermal.c b/drivers/acpi/thermal.c
new file mode 100644
index 0000000000..8263508415
--- /dev/null
+++ b/drivers/acpi/thermal.c
@@ -0,0 +1,1156 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *  acpi_thermal.c - ACPI Thermal Zone Driver ($Revision: 41 $)
+ *
+ *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
+ *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
+ *
+ *  This driver fully implements the ACPI thermal policy as described in the
+ *  ACPI 2.0 Specification.
+ *
+ *  TBD: 1. Implement passive cooling hysteresis.
+ *       2. Enhance passive cooling (CPU) states/limit interface to support
+ *          concepts of 'multiple limiters', upper/lower limits, etc.
+ */
+
+#define pr_fmt(fmt) "ACPI: thermal: " fmt
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/dmi.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/jiffies.h>
+#include <linux/kmod.h>
+#include <linux/reboot.h>
+#include <linux/device.h>
+#include <linux/thermal.h>
+#include <linux/acpi.h>
+#include <linux/workqueue.h>
+#include <linux/uaccess.h>
+#include <linux/units.h>
+
+#define ACPI_THERMAL_CLASS		"thermal_zone"
+#define ACPI_THERMAL_DEVICE_NAME	"Thermal Zone"
+#define ACPI_THERMAL_NOTIFY_TEMPERATURE	0x80
+#define ACPI_THERMAL_NOTIFY_THRESHOLDS	0x81
+#define ACPI_THERMAL_NOTIFY_DEVICES	0x82
+#define ACPI_THERMAL_NOTIFY_CRITICAL	0xF0
+#define ACPI_THERMAL_NOTIFY_HOT		0xF1
+#define ACPI_THERMAL_MODE_ACTIVE	0x00
+
+#define ACPI_THERMAL_MAX_ACTIVE		10
+#define ACPI_THERMAL_MAX_LIMIT_STR_LEN	65
+
+#define ACPI_TRIPS_CRITICAL	BIT(0)
+#define ACPI_TRIPS_HOT		BIT(1)
+#define ACPI_TRIPS_PASSIVE	BIT(2)
+#define ACPI_TRIPS_ACTIVE	BIT(3)
+#define ACPI_TRIPS_DEVICES	BIT(4)
+
+#define ACPI_TRIPS_THRESHOLDS	(ACPI_TRIPS_PASSIVE | ACPI_TRIPS_ACTIVE)
+
+#define ACPI_TRIPS_INIT		(ACPI_TRIPS_CRITICAL | ACPI_TRIPS_HOT | \
+				 ACPI_TRIPS_PASSIVE | ACPI_TRIPS_ACTIVE | \
+				 ACPI_TRIPS_DEVICES)
+
+/*
+ * This exception is thrown out in two cases:
+ * 1.An invalid trip point becomes invalid or a valid trip point becomes invalid
+ *   when re-evaluating the AML code.
+ * 2.TODO: Devices listed in _PSL, _ALx, _TZD may change.
+ *   We need to re-bind the cooling devices of a thermal zone when this occurs.
+ */
+#define ACPI_THERMAL_TRIPS_EXCEPTION(flags, tz, str) \
+do { \
+	if (flags != ACPI_TRIPS_INIT) \
+		acpi_handle_info(tz->device->handle, \
+			"ACPI thermal trip point %s changed\n" \
+			"Please report to linux-acpi@vger.kernel.org\n", str); \
+} while (0)
+
+static int act;
+module_param(act, int, 0644);
+MODULE_PARM_DESC(act, "Disable or override all lowest active trip points.");
+
+static int crt;
+module_param(crt, int, 0644);
+MODULE_PARM_DESC(crt, "Disable or lower all critical trip points.");
+
+static int tzp;
+module_param(tzp, int, 0444);
+MODULE_PARM_DESC(tzp, "Thermal zone polling frequency, in 1/10 seconds.");
+
+static int off;
+module_param(off, int, 0);
+MODULE_PARM_DESC(off, "Set to disable ACPI thermal support.");
+
+static int psv;
+module_param(psv, int, 0644);
+MODULE_PARM_DESC(psv, "Disable or override all passive trip points.");
+
+static struct workqueue_struct *acpi_thermal_pm_queue;
+
+struct acpi_thermal_trip {
+	unsigned long temperature;
+	bool valid;
+};
+
+struct acpi_thermal_passive {
+	struct acpi_thermal_trip trip;
+	struct acpi_handle_list devices;
+	unsigned long tc1;
+	unsigned long tc2;
+	unsigned long tsp;
+};
+
+struct acpi_thermal_active {
+	struct acpi_thermal_trip trip;
+	struct acpi_handle_list devices;
+};
+
+struct acpi_thermal_trips {
+	struct acpi_thermal_trip critical;
+	struct acpi_thermal_trip hot;
+	struct acpi_thermal_passive passive;
+	struct acpi_thermal_active active[ACPI_THERMAL_MAX_ACTIVE];
+};
+
+struct acpi_thermal {
+	struct acpi_device *device;
+	acpi_bus_id name;
+	unsigned long temperature;
+	unsigned long last_temperature;
+	unsigned long polling_frequency;
+	volatile u8 zombie;
+	struct acpi_thermal_trips trips;
+	struct thermal_trip *trip_table;
+	struct acpi_handle_list devices;
+	struct thermal_zone_device *thermal_zone;
+	int kelvin_offset;	/* in millidegrees */
+	struct work_struct thermal_check_work;
+	struct mutex thermal_check_lock;
+	refcount_t thermal_check_count;
+};
+
+/* --------------------------------------------------------------------------
+                             Thermal Zone Management
+   -------------------------------------------------------------------------- */
+
+static int acpi_thermal_get_temperature(struct acpi_thermal *tz)
+{
+	acpi_status status = AE_OK;
+	unsigned long long tmp;
+
+	if (!tz)
+		return -EINVAL;
+
+	tz->last_temperature = tz->temperature;
+
+	status = acpi_evaluate_integer(tz->device->handle, "_TMP", NULL, &tmp);
+	if (ACPI_FAILURE(status))
+		return -ENODEV;
+
+	tz->temperature = tmp;
+
+	acpi_handle_debug(tz->device->handle, "Temperature is %lu dK\n",
+			  tz->temperature);
+
+	return 0;
+}
+
+static int acpi_thermal_get_polling_frequency(struct acpi_thermal *tz)
+{
+	acpi_status status = AE_OK;
+	unsigned long long tmp;
+
+	if (!tz)
+		return -EINVAL;
+
+	status = acpi_evaluate_integer(tz->device->handle, "_TZP", NULL, &tmp);
+	if (ACPI_FAILURE(status))
+		return -ENODEV;
+
+	tz->polling_frequency = tmp;
+	acpi_handle_debug(tz->device->handle, "Polling frequency is %lu dS\n",
+			  tz->polling_frequency);
+
+	return 0;
+}
+
+static int acpi_thermal_temp(struct acpi_thermal *tz, int temp_deci_k)
+{
+	if (temp_deci_k == THERMAL_TEMP_INVALID)
+		return THERMAL_TEMP_INVALID;
+
+	return deci_kelvin_to_millicelsius_with_offset(temp_deci_k,
+						       tz->kelvin_offset);
+}
+
+static void __acpi_thermal_trips_update(struct acpi_thermal *tz, int flag)
+{
+	acpi_status status;
+	unsigned long long tmp;
+	struct acpi_handle_list devices;
+	bool valid = false;
+	int i;
+
+	/* Critical Shutdown */
+	if (flag & ACPI_TRIPS_CRITICAL) {
+		status = acpi_evaluate_integer(tz->device->handle, "_CRT", NULL, &tmp);
+		tz->trips.critical.temperature = tmp;
+		/*
+		 * Treat freezing temperatures as invalid as well; some
+		 * BIOSes return really low values and cause reboots at startup.
+		 * Below zero (Celsius) values clearly aren't right for sure..
+		 * ... so lets discard those as invalid.
+		 */
+		if (ACPI_FAILURE(status)) {
+			tz->trips.critical.valid = false;
+			acpi_handle_debug(tz->device->handle,
+					  "No critical threshold\n");
+		} else if (tmp <= 2732) {
+			pr_info(FW_BUG "Invalid critical threshold (%llu)\n", tmp);
+			tz->trips.critical.valid = false;
+		} else {
+			tz->trips.critical.valid = true;
+			acpi_handle_debug(tz->device->handle,
+					  "Found critical threshold [%lu]\n",
+					  tz->trips.critical.temperature);
+		}
+		if (tz->trips.critical.valid) {
+			if (crt == -1) {
+				tz->trips.critical.valid = false;
+			} else if (crt > 0) {
+				unsigned long crt_k = celsius_to_deci_kelvin(crt);
+
+				/*
+				 * Allow override critical threshold
+				 */
+				if (crt_k > tz->trips.critical.temperature)
+					pr_info("Critical threshold %d C\n", crt);
+
+				tz->trips.critical.temperature = crt_k;
+			}
+		}
+	}
+
+	/* Critical Sleep (optional) */
+	if (flag & ACPI_TRIPS_HOT) {
+		status = acpi_evaluate_integer(tz->device->handle, "_HOT", NULL, &tmp);
+		if (ACPI_FAILURE(status)) {
+			tz->trips.hot.valid = false;
+			acpi_handle_debug(tz->device->handle,
+					  "No hot threshold\n");
+		} else {
+			tz->trips.hot.temperature = tmp;
+			tz->trips.hot.valid = true;
+			acpi_handle_debug(tz->device->handle,
+					  "Found hot threshold [%lu]\n",
+					  tz->trips.hot.temperature);
+		}
+	}
+
+	/* Passive (optional) */
+	if (((flag & ACPI_TRIPS_PASSIVE) && tz->trips.passive.trip.valid) ||
+	    flag == ACPI_TRIPS_INIT) {
+		valid = tz->trips.passive.trip.valid;
+		if (psv == -1) {
+			status = AE_SUPPORT;
+		} else if (psv > 0) {
+			tmp = celsius_to_deci_kelvin(psv);
+			status = AE_OK;
+		} else {
+			status = acpi_evaluate_integer(tz->device->handle,
+						       "_PSV", NULL, &tmp);
+		}
+
+		if (ACPI_FAILURE(status)) {
+			tz->trips.passive.trip.valid = false;
+		} else {
+			tz->trips.passive.trip.temperature = tmp;
+			tz->trips.passive.trip.valid = true;
+			if (flag == ACPI_TRIPS_INIT) {
+				status = acpi_evaluate_integer(tz->device->handle,
+							       "_TC1", NULL, &tmp);
+				if (ACPI_FAILURE(status))
+					tz->trips.passive.trip.valid = false;
+				else
+					tz->trips.passive.tc1 = tmp;
+
+				status = acpi_evaluate_integer(tz->device->handle,
+							       "_TC2", NULL, &tmp);
+				if (ACPI_FAILURE(status))
+					tz->trips.passive.trip.valid = false;
+				else
+					tz->trips.passive.tc2 = tmp;
+
+				status = acpi_evaluate_integer(tz->device->handle,
+							       "_TSP", NULL, &tmp);
+				if (ACPI_FAILURE(status))
+					tz->trips.passive.trip.valid = false;
+				else
+					tz->trips.passive.tsp = tmp;
+			}
+		}
+	}
+	if ((flag & ACPI_TRIPS_DEVICES) && tz->trips.passive.trip.valid) {
+		memset(&devices, 0, sizeof(struct acpi_handle_list));
+		status = acpi_evaluate_reference(tz->device->handle, "_PSL",
+						 NULL, &devices);
+		if (ACPI_FAILURE(status)) {
+			acpi_handle_info(tz->device->handle,
+					 "Invalid passive threshold\n");
+			tz->trips.passive.trip.valid = false;
+		} else {
+			tz->trips.passive.trip.valid = true;
+		}
+
+		if (memcmp(&tz->trips.passive.devices, &devices,
+			   sizeof(struct acpi_handle_list))) {
+			memcpy(&tz->trips.passive.devices, &devices,
+			       sizeof(struct acpi_handle_list));
+			ACPI_THERMAL_TRIPS_EXCEPTION(flag, tz, "device");
+		}
+	}
+	if ((flag & ACPI_TRIPS_PASSIVE) || (flag & ACPI_TRIPS_DEVICES)) {
+		if (valid != tz->trips.passive.trip.valid)
+			ACPI_THERMAL_TRIPS_EXCEPTION(flag, tz, "state");
+	}
+
+	/* Active (optional) */
+	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
+		char name[5] = { '_', 'A', 'C', ('0' + i), '\0' };
+		valid = tz->trips.active[i].trip.valid;
+
+		if (act == -1)
+			break; /* disable all active trip points */
+
+		if (flag == ACPI_TRIPS_INIT || ((flag & ACPI_TRIPS_ACTIVE) &&
+		    tz->trips.active[i].trip.valid)) {
+			status = acpi_evaluate_integer(tz->device->handle,
+						       name, NULL, &tmp);
+			if (ACPI_FAILURE(status)) {
+				tz->trips.active[i].trip.valid = false;
+				if (i == 0)
+					break;
+
+				if (act <= 0)
+					break;
+
+				if (i == 1)
+					tz->trips.active[0].trip.temperature =
+							celsius_to_deci_kelvin(act);
+				else
+					/*
+					 * Don't allow override higher than
+					 * the next higher trip point
+					 */
+					tz->trips.active[i-1].trip.temperature =
+						min_t(unsigned long,
+						      tz->trips.active[i-2].trip.temperature,
+						      celsius_to_deci_kelvin(act));
+
+				break;
+			} else {
+				tz->trips.active[i].trip.temperature = tmp;
+				tz->trips.active[i].trip.valid = true;
+			}
+		}
+
+		name[2] = 'L';
+		if ((flag & ACPI_TRIPS_DEVICES) && tz->trips.active[i].trip.valid) {
+			memset(&devices, 0, sizeof(struct acpi_handle_list));
+			status = acpi_evaluate_reference(tz->device->handle,
+							 name, NULL, &devices);
+			if (ACPI_FAILURE(status)) {
+				acpi_handle_info(tz->device->handle,
+						 "Invalid active%d threshold\n", i);
+				tz->trips.active[i].trip.valid = false;
+			} else {
+				tz->trips.active[i].trip.valid = true;
+			}
+
+			if (memcmp(&tz->trips.active[i].devices, &devices,
+				   sizeof(struct acpi_handle_list))) {
+				memcpy(&tz->trips.active[i].devices, &devices,
+				       sizeof(struct acpi_handle_list));
+				ACPI_THERMAL_TRIPS_EXCEPTION(flag, tz, "device");
+			}
+		}
+		if ((flag & ACPI_TRIPS_ACTIVE) || (flag & ACPI_TRIPS_DEVICES))
+			if (valid != tz->trips.active[i].trip.valid)
+				ACPI_THERMAL_TRIPS_EXCEPTION(flag, tz, "state");
+
+		if (!tz->trips.active[i].trip.valid)
+			break;
+	}
+
+	if (flag & ACPI_TRIPS_DEVICES) {
+		memset(&devices, 0, sizeof(devices));
+		status = acpi_evaluate_reference(tz->device->handle, "_TZD",
+						 NULL, &devices);
+		if (ACPI_SUCCESS(status) &&
+		    memcmp(&tz->devices, &devices, sizeof(devices))) {
+			tz->devices = devices;
+			ACPI_THERMAL_TRIPS_EXCEPTION(flag, tz, "device");
+		}
+	}
+}
+
+static int acpi_thermal_adjust_trip(struct thermal_trip *trip, void *data)
+{
+	struct acpi_thermal_trip *acpi_trip = trip->priv;
+	struct acpi_thermal *tz = data;
+
+	if (!acpi_trip)
+		return 0;
+
+	if (acpi_trip->valid)
+		trip->temperature = acpi_thermal_temp(tz, acpi_trip->temperature);
+	else
+		trip->temperature = THERMAL_TEMP_INVALID;
+
+	return 0;
+}
+
+static void acpi_thermal_adjust_thermal_zone(struct thermal_zone_device *thermal,
+					     unsigned long data)
+{
+	struct acpi_thermal *tz = thermal_zone_device_priv(thermal);
+	int flag = data == ACPI_THERMAL_NOTIFY_THRESHOLDS ?
+				ACPI_TRIPS_THRESHOLDS : ACPI_TRIPS_DEVICES;
+
+	__acpi_thermal_trips_update(tz, flag);
+
+	for_each_thermal_trip(tz->thermal_zone, acpi_thermal_adjust_trip, tz);
+}
+
+static void acpi_queue_thermal_check(struct acpi_thermal *tz)
+{
+	if (!work_pending(&tz->thermal_check_work))
+		queue_work(acpi_thermal_pm_queue, &tz->thermal_check_work);
+}
+
+static void acpi_thermal_trips_update(struct acpi_thermal *tz, u32 event)
+{
+	struct acpi_device *adev = tz->device;
+
+	/*
+	 * Use thermal_zone_device_exec() to carry out the trip points
+	 * update, so as to protect thermal_get_trend() from getting stale
+	 * trip point temperatures and to prevent thermal_zone_device_update()
+	 * invoked from acpi_thermal_check_fn() from producing inconsistent
+	 * results.
+	 */
+	thermal_zone_device_exec(tz->thermal_zone,
+				 acpi_thermal_adjust_thermal_zone, event);
+	acpi_queue_thermal_check(tz);
+	acpi_bus_generate_netlink_event(adev->pnp.device_class,
+					dev_name(&adev->dev), event, 0);
+}
+
+static int acpi_thermal_get_trip_points(struct acpi_thermal *tz)
+{
+	bool valid;
+	int i;
+
+	__acpi_thermal_trips_update(tz, ACPI_TRIPS_INIT);
+
+	valid = tz->trips.critical.valid |
+		tz->trips.hot.valid |
+		tz->trips.passive.trip.valid;
+
+	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++)
+		valid = valid || tz->trips.active[i].trip.valid;
+
+	if (!valid) {
+		pr_warn(FW_BUG "No valid trip found\n");
+		return -ENODEV;
+	}
+	return 0;
+}
+
+/* sys I/F for generic thermal sysfs support */
+
+static int thermal_get_temp(struct thermal_zone_device *thermal, int *temp)
+{
+	struct acpi_thermal *tz = thermal_zone_device_priv(thermal);
+	int result;
+
+	if (!tz)
+		return -EINVAL;
+
+	result = acpi_thermal_get_temperature(tz);
+	if (result)
+		return result;
+
+	*temp = deci_kelvin_to_millicelsius_with_offset(tz->temperature,
+							tz->kelvin_offset);
+	return 0;
+}
+
+static int thermal_get_trend(struct thermal_zone_device *thermal,
+			     const struct thermal_trip *trip,
+			     enum thermal_trend *trend)
+{
+	struct acpi_thermal *tz = thermal_zone_device_priv(thermal);
+	struct acpi_thermal_trip *acpi_trip;
+	int t;
+
+	if (!tz || !trip)
+		return -EINVAL;
+
+	acpi_trip = trip->priv;
+	if (!acpi_trip || !acpi_trip->valid)
+		return -EINVAL;
+
+	switch (trip->type) {
+	case THERMAL_TRIP_PASSIVE:
+		t = tz->trips.passive.tc1 * (tz->temperature -
+						tz->last_temperature) +
+			tz->trips.passive.tc2 * (tz->temperature -
+						acpi_trip->temperature);
+		if (t > 0)
+			*trend = THERMAL_TREND_RAISING;
+		else if (t < 0)
+			*trend = THERMAL_TREND_DROPPING;
+		else
+			*trend = THERMAL_TREND_STABLE;
+
+		return 0;
+
+	case THERMAL_TRIP_ACTIVE:
+		t = acpi_thermal_temp(tz, tz->temperature);
+		if (t <= trip->temperature)
+			break;
+
+		*trend = THERMAL_TREND_RAISING;
+
+		return 0;
+
+	default:
+		break;
+	}
+
+	return -EINVAL;
+}
+
+static void acpi_thermal_zone_device_hot(struct thermal_zone_device *thermal)
+{
+	struct acpi_thermal *tz = thermal_zone_device_priv(thermal);
+
+	acpi_bus_generate_netlink_event(tz->device->pnp.device_class,
+					dev_name(&tz->device->dev),
+					ACPI_THERMAL_NOTIFY_HOT, 1);
+}
+
+static void acpi_thermal_zone_device_critical(struct thermal_zone_device *thermal)
+{
+	struct acpi_thermal *tz = thermal_zone_device_priv(thermal);
+
+	acpi_bus_generate_netlink_event(tz->device->pnp.device_class,
+					dev_name(&tz->device->dev),
+					ACPI_THERMAL_NOTIFY_CRITICAL, 1);
+
+	thermal_zone_device_critical(thermal);
+}
+
+static int acpi_thermal_cooling_device_cb(struct thermal_zone_device *thermal,
+					  struct thermal_cooling_device *cdev,
+					  bool bind)
+{
+	struct acpi_device *device = cdev->devdata;
+	struct acpi_thermal *tz = thermal_zone_device_priv(thermal);
+	struct acpi_device *dev;
+	acpi_handle handle;
+	int i;
+	int j;
+	int trip = -1;
+	int result = 0;
+
+	if (tz->trips.critical.valid)
+		trip++;
+
+	if (tz->trips.hot.valid)
+		trip++;
+
+	if (tz->trips.passive.trip.valid) {
+		trip++;
+		for (i = 0; i < tz->trips.passive.devices.count; i++) {
+			handle = tz->trips.passive.devices.handles[i];
+			dev = acpi_fetch_acpi_dev(handle);
+			if (dev != device)
+				continue;
+
+			if (bind)
+				result = thermal_zone_bind_cooling_device(
+						thermal, trip, cdev,
+						THERMAL_NO_LIMIT,
+						THERMAL_NO_LIMIT,
+						THERMAL_WEIGHT_DEFAULT);
+			else
+				result =
+					thermal_zone_unbind_cooling_device(
+						thermal, trip, cdev);
+
+			if (result)
+				goto failed;
+		}
+	}
+
+	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
+		if (!tz->trips.active[i].trip.valid)
+			break;
+
+		trip++;
+		for (j = 0; j < tz->trips.active[i].devices.count; j++) {
+			handle = tz->trips.active[i].devices.handles[j];
+			dev = acpi_fetch_acpi_dev(handle);
+			if (dev != device)
+				continue;
+
+			if (bind)
+				result = thermal_zone_bind_cooling_device(
+						thermal, trip, cdev,
+						THERMAL_NO_LIMIT,
+						THERMAL_NO_LIMIT,
+						THERMAL_WEIGHT_DEFAULT);
+			else
+				result = thermal_zone_unbind_cooling_device(
+						thermal, trip, cdev);
+
+			if (result)
+				goto failed;
+		}
+	}
+
+failed:
+	return result;
+}
+
+static int
+acpi_thermal_bind_cooling_device(struct thermal_zone_device *thermal,
+				 struct thermal_cooling_device *cdev)
+{
+	return acpi_thermal_cooling_device_cb(thermal, cdev, true);
+}
+
+static int
+acpi_thermal_unbind_cooling_device(struct thermal_zone_device *thermal,
+				   struct thermal_cooling_device *cdev)
+{
+	return acpi_thermal_cooling_device_cb(thermal, cdev, false);
+}
+
+static struct thermal_zone_device_ops acpi_thermal_zone_ops = {
+	.bind = acpi_thermal_bind_cooling_device,
+	.unbind	= acpi_thermal_unbind_cooling_device,
+	.get_temp = thermal_get_temp,
+	.get_trend = thermal_get_trend,
+	.hot = acpi_thermal_zone_device_hot,
+	.critical = acpi_thermal_zone_device_critical,
+};
+
+static int acpi_thermal_zone_sysfs_add(struct acpi_thermal *tz)
+{
+	struct device *tzdev = thermal_zone_device(tz->thermal_zone);
+	int ret;
+
+	ret = sysfs_create_link(&tz->device->dev.kobj,
+				&tzdev->kobj, "thermal_zone");
+	if (ret)
+		return ret;
+
+	ret = sysfs_create_link(&tzdev->kobj,
+				   &tz->device->dev.kobj, "device");
+	if (ret)
+		sysfs_remove_link(&tz->device->dev.kobj, "thermal_zone");
+
+	return ret;
+}
+
+static void acpi_thermal_zone_sysfs_remove(struct acpi_thermal *tz)
+{
+	struct device *tzdev = thermal_zone_device(tz->thermal_zone);
+
+	sysfs_remove_link(&tz->device->dev.kobj, "thermal_zone");
+	sysfs_remove_link(&tzdev->kobj, "device");
+}
+
+static int acpi_thermal_register_thermal_zone(struct acpi_thermal *tz)
+{
+	struct acpi_thermal_trip *acpi_trip;
+	struct thermal_trip *trip;
+	int passive_delay = 0;
+	int trip_count = 0;
+	int result;
+	int i;
+
+	if (tz->trips.critical.valid)
+		trip_count++;
+
+	if (tz->trips.hot.valid)
+		trip_count++;
+
+	if (tz->trips.passive.trip.valid) {
+		trip_count++;
+		passive_delay = tz->trips.passive.tsp * 100;
+	}
+
+	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE && tz->trips.active[i].trip.valid; i++)
+		trip_count++;
+
+	trip = kcalloc(trip_count, sizeof(*trip), GFP_KERNEL);
+	if (!trip)
+		return -ENOMEM;
+
+	tz->trip_table = trip;
+
+	if (tz->trips.critical.valid) {
+		trip->type = THERMAL_TRIP_CRITICAL;
+		trip->temperature = acpi_thermal_temp(tz, tz->trips.critical.temperature);
+		trip++;
+	}
+
+	if (tz->trips.hot.valid) {
+		trip->type = THERMAL_TRIP_HOT;
+		trip->temperature = acpi_thermal_temp(tz, tz->trips.hot.temperature);
+		trip++;
+	}
+
+	acpi_trip = &tz->trips.passive.trip;
+	if (acpi_trip->valid) {
+		trip->type = THERMAL_TRIP_PASSIVE;
+		trip->temperature = acpi_thermal_temp(tz, acpi_trip->temperature);
+		trip->priv = acpi_trip;
+		trip++;
+	}
+
+	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
+		acpi_trip = &tz->trips.active[i].trip;
+
+		if (!acpi_trip->valid)
+			break;
+
+		trip->type = THERMAL_TRIP_ACTIVE;
+		trip->temperature = acpi_thermal_temp(tz, acpi_trip->temperature);
+		trip->priv = acpi_trip;
+		trip++;
+	}
+
+	tz->thermal_zone = thermal_zone_device_register_with_trips("acpitz",
+								   tz->trip_table,
+								   trip_count,
+								   0, tz,
+								   &acpi_thermal_zone_ops,
+								   NULL,
+								   passive_delay,
+								   tz->polling_frequency * 100);
+	if (IS_ERR(tz->thermal_zone)) {
+		result = PTR_ERR(tz->thermal_zone);
+		goto free_trip_table;
+	}
+
+	result = acpi_thermal_zone_sysfs_add(tz);
+	if (result)
+		goto unregister_tzd;
+
+	result = thermal_zone_device_enable(tz->thermal_zone);
+	if (result)
+		goto remove_links;
+
+	dev_info(&tz->device->dev, "registered as thermal_zone%d\n",
+		 thermal_zone_device_id(tz->thermal_zone));
+
+	return 0;
+
+remove_links:
+	acpi_thermal_zone_sysfs_remove(tz);
+unregister_tzd:
+	thermal_zone_device_unregister(tz->thermal_zone);
+free_trip_table:
+	kfree(tz->trip_table);
+
+	return result;
+}
+
+static void acpi_thermal_unregister_thermal_zone(struct acpi_thermal *tz)
+{
+	thermal_zone_device_disable(tz->thermal_zone);
+	acpi_thermal_zone_sysfs_remove(tz);
+	thermal_zone_device_unregister(tz->thermal_zone);
+	tz->thermal_zone = NULL;
+}
+
+
+/* --------------------------------------------------------------------------
+                                 Driver Interface
+   -------------------------------------------------------------------------- */
+
+static void acpi_thermal_notify(acpi_handle handle, u32 event, void *data)
+{
+	struct acpi_device *device = data;
+	struct acpi_thermal *tz = acpi_driver_data(device);
+
+	if (!tz)
+		return;
+
+	switch (event) {
+	case ACPI_THERMAL_NOTIFY_TEMPERATURE:
+		acpi_queue_thermal_check(tz);
+		break;
+	case ACPI_THERMAL_NOTIFY_THRESHOLDS:
+	case ACPI_THERMAL_NOTIFY_DEVICES:
+		acpi_thermal_trips_update(tz, event);
+		break;
+	default:
+		acpi_handle_debug(device->handle, "Unsupported event [0x%x]\n",
+				  event);
+		break;
+	}
+}
+
+/*
+ * On some platforms, the AML code has dependency about
+ * the evaluating order of _TMP and _CRT/_HOT/_PSV/_ACx.
+ * 1. On HP Pavilion G4-1016tx, _TMP must be invoked after
+ *    /_CRT/_HOT/_PSV/_ACx, or else system will be power off.
+ * 2. On HP Compaq 6715b/6715s, the return value of _PSV is 0
+ *    if _TMP has never been evaluated.
+ *
+ * As this dependency is totally transparent to OS, evaluate
+ * all of them once, in the order of _CRT/_HOT/_PSV/_ACx,
+ * _TMP, before they are actually used.
+ */
+static void acpi_thermal_aml_dependency_fix(struct acpi_thermal *tz)
+{
+	acpi_handle handle = tz->device->handle;
+	unsigned long long value;
+	int i;
+
+	acpi_evaluate_integer(handle, "_CRT", NULL, &value);
+	acpi_evaluate_integer(handle, "_HOT", NULL, &value);
+	acpi_evaluate_integer(handle, "_PSV", NULL, &value);
+	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
+		char name[5] = { '_', 'A', 'C', ('0' + i), '\0' };
+		acpi_status status;
+
+		status = acpi_evaluate_integer(handle, name, NULL, &value);
+		if (status == AE_NOT_FOUND)
+			break;
+	}
+	acpi_evaluate_integer(handle, "_TMP", NULL, &value);
+}
+
+static int acpi_thermal_get_info(struct acpi_thermal *tz)
+{
+	int result;
+
+	if (!tz)
+		return -EINVAL;
+
+	acpi_thermal_aml_dependency_fix(tz);
+
+	/* Get trip points [_CRT, _PSV, etc.] (required) */
+	result = acpi_thermal_get_trip_points(tz);
+	if (result)
+		return result;
+
+	/* Get temperature [_TMP] (required) */
+	result = acpi_thermal_get_temperature(tz);
+	if (result)
+		return result;
+
+	/* Set the cooling mode [_SCP] to active cooling (default) */
+	acpi_execute_simple_method(tz->device->handle, "_SCP",
+				   ACPI_THERMAL_MODE_ACTIVE);
+
+	/* Get default polling frequency [_TZP] (optional) */
+	if (tzp)
+		tz->polling_frequency = tzp;
+	else
+		acpi_thermal_get_polling_frequency(tz);
+
+	return 0;
+}
+
+/*
+ * The exact offset between Kelvin and degree Celsius is 273.15. However ACPI
+ * handles temperature values with a single decimal place. As a consequence,
+ * some implementations use an offset of 273.1 and others use an offset of
+ * 273.2. Try to find out which one is being used, to present the most
+ * accurate and visually appealing number.
+ *
+ * The heuristic below should work for all ACPI thermal zones which have a
+ * critical trip point with a value being a multiple of 0.5 degree Celsius.
+ */
+static void acpi_thermal_guess_offset(struct acpi_thermal *tz)
+{
+	if (tz->trips.critical.valid &&
+	    (tz->trips.critical.temperature % 5) == 1)
+		tz->kelvin_offset = 273100;
+	else
+		tz->kelvin_offset = 273200;
+}
+
+static void acpi_thermal_check_fn(struct work_struct *work)
+{
+	struct acpi_thermal *tz = container_of(work, struct acpi_thermal,
+					       thermal_check_work);
+
+	/*
+	 * In general, it is not sufficient to check the pending bit, because
+	 * subsequent instances of this function may be queued after one of them
+	 * has started running (e.g. if _TMP sleeps).  Avoid bailing out if just
+	 * one of them is running, though, because it may have done the actual
+	 * check some time ago, so allow at least one of them to block on the
+	 * mutex while another one is running the update.
+	 */
+	if (!refcount_dec_not_one(&tz->thermal_check_count))
+		return;
+
+	mutex_lock(&tz->thermal_check_lock);
+
+	thermal_zone_device_update(tz->thermal_zone, THERMAL_EVENT_UNSPECIFIED);
+
+	refcount_inc(&tz->thermal_check_count);
+
+	mutex_unlock(&tz->thermal_check_lock);
+}
+
+static int acpi_thermal_add(struct acpi_device *device)
+{
+	struct acpi_thermal *tz;
+	int result;
+
+	if (!device)
+		return -EINVAL;
+
+	tz = kzalloc(sizeof(struct acpi_thermal), GFP_KERNEL);
+	if (!tz)
+		return -ENOMEM;
+
+	tz->device = device;
+	strcpy(tz->name, device->pnp.bus_id);
+	strcpy(acpi_device_name(device), ACPI_THERMAL_DEVICE_NAME);
+	strcpy(acpi_device_class(device), ACPI_THERMAL_CLASS);
+	device->driver_data = tz;
+
+	result = acpi_thermal_get_info(tz);
+	if (result)
+		goto free_memory;
+
+	acpi_thermal_guess_offset(tz);
+
+	result = acpi_thermal_register_thermal_zone(tz);
+	if (result)
+		goto free_memory;
+
+	refcount_set(&tz->thermal_check_count, 3);
+	mutex_init(&tz->thermal_check_lock);
+	INIT_WORK(&tz->thermal_check_work, acpi_thermal_check_fn);
+
+	pr_info("%s [%s] (%ld C)\n", acpi_device_name(device),
+		acpi_device_bid(device), deci_kelvin_to_celsius(tz->temperature));
+
+	result = acpi_dev_install_notify_handler(device, ACPI_DEVICE_NOTIFY,
+						 acpi_thermal_notify);
+	if (result)
+		goto flush_wq;
+
+	return 0;
+
+flush_wq:
+	flush_workqueue(acpi_thermal_pm_queue);
+	acpi_thermal_unregister_thermal_zone(tz);
+free_memory:
+	kfree(tz);
+
+	return result;
+}
+
+static void acpi_thermal_remove(struct acpi_device *device)
+{
+	struct acpi_thermal *tz;
+
+	if (!device || !acpi_driver_data(device))
+		return;
+
+	tz = acpi_driver_data(device);
+
+	acpi_dev_remove_notify_handler(device, ACPI_DEVICE_NOTIFY,
+				       acpi_thermal_notify);
+
+	flush_workqueue(acpi_thermal_pm_queue);
+	acpi_thermal_unregister_thermal_zone(tz);
+	kfree(tz->trip_table);
+	kfree(tz);
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int acpi_thermal_suspend(struct device *dev)
+{
+	/* Make sure the previously queued thermal check work has been done */
+	flush_workqueue(acpi_thermal_pm_queue);
+	return 0;
+}
+
+static int acpi_thermal_resume(struct device *dev)
+{
+	struct acpi_thermal *tz;
+	int i, j, power_state;
+
+	if (!dev)
+		return -EINVAL;
+
+	tz = acpi_driver_data(to_acpi_device(dev));
+	if (!tz)
+		return -EINVAL;
+
+	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
+		if (!tz->trips.active[i].trip.valid)
+			break;
+
+		for (j = 0; j < tz->trips.active[i].devices.count; j++) {
+			acpi_bus_update_power(tz->trips.active[i].devices.handles[j],
+					      &power_state);
+		}
+	}
+
+	acpi_queue_thermal_check(tz);
+
+	return AE_OK;
+}
+#else
+#define acpi_thermal_suspend	NULL
+#define acpi_thermal_resume	NULL
+#endif
+static SIMPLE_DEV_PM_OPS(acpi_thermal_pm, acpi_thermal_suspend, acpi_thermal_resume);
+
+static const struct acpi_device_id  thermal_device_ids[] = {
+	{ACPI_THERMAL_HID, 0},
+	{"", 0},
+};
+MODULE_DEVICE_TABLE(acpi, thermal_device_ids);
+
+static struct acpi_driver acpi_thermal_driver = {
+	.name = "thermal",
+	.class = ACPI_THERMAL_CLASS,
+	.ids = thermal_device_ids,
+	.ops = {
+		.add = acpi_thermal_add,
+		.remove = acpi_thermal_remove,
+		},
+	.drv.pm = &acpi_thermal_pm,
+};
+
+static int thermal_act(const struct dmi_system_id *d) {
+	if (act == 0) {
+		pr_notice("%s detected: disabling all active thermal trip points\n",
+			  d->ident);
+		act = -1;
+	}
+	return 0;
+}
+static int thermal_nocrt(const struct dmi_system_id *d) {
+	pr_notice("%s detected: disabling all critical thermal trip point actions.\n",
+		  d->ident);
+	crt = -1;
+	return 0;
+}
+static int thermal_tzp(const struct dmi_system_id *d) {
+	if (tzp == 0) {
+		pr_notice("%s detected: enabling thermal zone polling\n",
+			  d->ident);
+		tzp = 300;	/* 300 dS = 30 Seconds */
+	}
+	return 0;
+}
+static int thermal_psv(const struct dmi_system_id *d) {
+	if (psv == 0) {
+		pr_notice("%s detected: disabling all passive thermal trip points\n",
+			  d->ident);
+		psv = -1;
+	}
+	return 0;
+}
+
+static const struct dmi_system_id thermal_dmi_table[] __initconst = {
+	/*
+	 * Award BIOS on this AOpen makes thermal control almost worthless.
+	 * http://bugzilla.kernel.org/show_bug.cgi?id=8842
+	 */
+	{
+	 .callback = thermal_act,
+	 .ident = "AOpen i915GMm-HFS",
+	 .matches = {
+		DMI_MATCH(DMI_BOARD_VENDOR, "AOpen"),
+		DMI_MATCH(DMI_BOARD_NAME, "i915GMm-HFS"),
+		},
+	},
+	{
+	 .callback = thermal_psv,
+	 .ident = "AOpen i915GMm-HFS",
+	 .matches = {
+		DMI_MATCH(DMI_BOARD_VENDOR, "AOpen"),
+		DMI_MATCH(DMI_BOARD_NAME, "i915GMm-HFS"),
+		},
+	},
+	{
+	 .callback = thermal_tzp,
+	 .ident = "AOpen i915GMm-HFS",
+	 .matches = {
+		DMI_MATCH(DMI_BOARD_VENDOR, "AOpen"),
+		DMI_MATCH(DMI_BOARD_NAME, "i915GMm-HFS"),
+		},
+	},
+	{
+	 .callback = thermal_nocrt,
+	 .ident = "Gigabyte GA-7ZX",
+	 .matches = {
+		DMI_MATCH(DMI_BOARD_VENDOR, "Gigabyte Technology Co., Ltd."),
+		DMI_MATCH(DMI_BOARD_NAME, "7ZX"),
+		},
+	},
+	{}
+};
+
+static int __init acpi_thermal_init(void)
+{
+	int result;
+
+	dmi_check_system(thermal_dmi_table);
+
+	if (off) {
+		pr_notice("thermal control disabled\n");
+		return -ENODEV;
+	}
+
+	acpi_thermal_pm_queue = alloc_workqueue("acpi_thermal_pm",
+						WQ_HIGHPRI | WQ_MEM_RECLAIM, 0);
+	if (!acpi_thermal_pm_queue)
+		return -ENODEV;
+
+	result = acpi_bus_register_driver(&acpi_thermal_driver);
+	if (result < 0) {
+		destroy_workqueue(acpi_thermal_pm_queue);
+		return -ENODEV;
+	}
+
+	return 0;
+}
+
+static void __exit acpi_thermal_exit(void)
+{
+	acpi_bus_unregister_driver(&acpi_thermal_driver);
+	destroy_workqueue(acpi_thermal_pm_queue);
+}
+
+module_init(acpi_thermal_init);
+module_exit(acpi_thermal_exit);
+
+MODULE_AUTHOR("Paul Diefenbaugh");
+MODULE_DESCRIPTION("ACPI Thermal Zone Driver");
+MODULE_LICENSE("GPL");