patch-2.4.22 linux-2.4.22/drivers/acpi/thermal.c

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diff -urN linux-2.4.21/drivers/acpi/thermal.c linux-2.4.22/drivers/acpi/thermal.c
@@ -0,0 +1,1359 @@
+/*
+ *  acpi_thermal.c - ACPI Thermal Zone Driver ($Revision: 40 $)
+ *
+ *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
+ *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or (at
+ *  your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful, but
+ *  WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ *  General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License along
+ *  with this program; if not, write to the Free Software Foundation, Inc.,
+ *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ *  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.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/compatmac.h>
+#include <linux/proc_fs.h>
+#include <linux/sched.h>
+#include <linux/kmod.h>
+#include <acpi/acpi_bus.h>
+#include <acpi/acpi_drivers.h>
+
+
+#define _COMPONENT		ACPI_THERMAL_COMPONENT
+ACPI_MODULE_NAME		("acpi_thermal")
+
+MODULE_AUTHOR("Paul Diefenbaugh");
+MODULE_DESCRIPTION(ACPI_THERMAL_DRIVER_NAME);
+MODULE_LICENSE("GPL");
+
+static int tzp = 0;
+MODULE_PARM(tzp, "i");
+MODULE_PARM_DESC(tzp, "Thermal zone polling frequency, in 1/10 seconds.\n");
+
+#define PREFIX			"ACPI: "
+
+
+#define ACPI_THERMAL_MAX_ACTIVE	10
+
+#define KELVIN_TO_CELSIUS(t)    (long)(((long)t-2732>=0) ? ((long)t-2732+5)/10 : ((long)t-2732-5)/10)
+#define CELSIUS_TO_KELVIN(t)	((t+273)*10)
+
+static int acpi_thermal_add (struct acpi_device *device);
+static int acpi_thermal_remove (struct acpi_device *device, int type);
+
+static struct acpi_driver acpi_thermal_driver = {
+	.name =		ACPI_THERMAL_DRIVER_NAME,
+	.class =	ACPI_THERMAL_CLASS,
+	.ids =		ACPI_THERMAL_HID,
+	.ops =		{
+				.add =		acpi_thermal_add,
+				.remove =	acpi_thermal_remove,
+			},
+};
+
+struct acpi_thermal_state {
+	u8			critical:1;
+	u8			hot:1;
+	u8			passive:1;
+	u8			active:1;
+	u8			reserved:4;
+	int			active_index;
+};
+
+struct acpi_thermal_state_flags {
+	u8			valid:1;
+	u8			enabled:1;
+	u8			reserved:6;
+};
+
+struct acpi_thermal_critical {
+	struct acpi_thermal_state_flags flags;
+	unsigned long		temperature;
+};
+
+struct acpi_thermal_hot {
+	struct acpi_thermal_state_flags flags;
+	unsigned long		temperature;
+};
+
+struct acpi_thermal_passive {
+	struct acpi_thermal_state_flags flags;
+	unsigned long		temperature;
+	unsigned long		tc1;
+	unsigned long		tc2;
+	unsigned long		tsp;
+	struct acpi_handle_list	devices;
+};
+
+struct acpi_thermal_active {
+	struct acpi_thermal_state_flags flags;
+	unsigned long		temperature;
+	struct acpi_handle_list	devices;
+};
+
+struct acpi_thermal_trips {
+	struct acpi_thermal_critical critical;
+	struct acpi_thermal_hot	hot;
+	struct acpi_thermal_passive passive;
+	struct acpi_thermal_active active[ACPI_THERMAL_MAX_ACTIVE];
+};
+
+struct acpi_thermal_flags {
+	u8			cooling_mode:1;		/* _SCP */
+	u8			devices:1;		/* _TZD */
+	u8			reserved:6;
+};
+
+struct acpi_thermal {
+	acpi_handle		handle;
+	acpi_bus_id		name;
+	unsigned long		temperature;
+	unsigned long		last_temperature;
+	unsigned long		polling_frequency;
+	u8			cooling_mode;
+	struct acpi_thermal_flags flags;
+	struct acpi_thermal_state state;
+	struct acpi_thermal_trips trips;
+	struct acpi_handle_list	devices;
+	struct timer_list	timer;
+};
+
+
+/* --------------------------------------------------------------------------
+                             Thermal Zone Management
+   -------------------------------------------------------------------------- */
+
+static int
+acpi_thermal_get_temperature (
+	struct acpi_thermal *tz)
+{
+	acpi_status		status = AE_OK;
+
+	ACPI_FUNCTION_TRACE("acpi_thermal_get_temperature");
+
+	if (!tz)
+		return_VALUE(-EINVAL);
+
+	tz->last_temperature = tz->temperature;
+
+	status = acpi_evaluate_integer(tz->handle, "_TMP", NULL, &tz->temperature);
+	if (ACPI_FAILURE(status))
+		return -ENODEV;
+
+	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Temperature is %lu dK\n", tz->temperature));
+
+	return_VALUE(0);
+}
+
+
+static int
+acpi_thermal_get_polling_frequency (
+	struct acpi_thermal	*tz)
+{
+	acpi_status		status = AE_OK;
+
+	ACPI_FUNCTION_TRACE("acpi_thermal_get_polling_frequency");
+
+	if (!tz)
+		return_VALUE(-EINVAL);
+
+	status = acpi_evaluate_integer(tz->handle, "_TZP", NULL, &tz->polling_frequency);
+	if (ACPI_FAILURE(status))
+		return_VALUE(-ENODEV);
+
+	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Polling frequency is %lu dS\n", tz->polling_frequency));
+
+	return_VALUE(0);
+}
+
+
+static int
+acpi_thermal_set_polling (
+	struct acpi_thermal	*tz,
+	int			seconds)
+{
+	ACPI_FUNCTION_TRACE("acpi_thermal_set_polling");
+
+	if (!tz)
+		return_VALUE(-EINVAL);
+
+	tz->polling_frequency = seconds * 10;	/* Convert value to deci-seconds */
+
+	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Polling frequency set to %lu seconds\n", tz->polling_frequency));
+
+	return_VALUE(0);
+}
+
+
+static int
+acpi_thermal_set_cooling_mode (
+	struct acpi_thermal	*tz,
+	int			mode)
+{
+	acpi_status		status = AE_OK;
+	union acpi_object	arg0 = {ACPI_TYPE_INTEGER};
+	struct acpi_object_list	arg_list = {1, &arg0};
+	acpi_handle		handle = NULL;
+
+	ACPI_FUNCTION_TRACE("acpi_thermal_set_cooling_mode");
+
+	if (!tz)
+		return_VALUE(-EINVAL);
+
+	status = acpi_get_handle(tz->handle, "_SCP", &handle);
+	if (ACPI_FAILURE(status)) {
+		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "_SCP not present\n"));
+		return_VALUE(-ENODEV);
+	}
+
+	arg0.integer.value = mode;
+
+	status = acpi_evaluate_object(handle, NULL, &arg_list, NULL);
+	if (ACPI_FAILURE(status))
+		return_VALUE(-ENODEV);
+
+	tz->cooling_mode = mode;
+
+	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Cooling mode [%s]\n", 
+		mode?"passive":"active"));
+
+	return_VALUE(0);
+}
+
+
+static int
+acpi_thermal_get_trip_points (
+	struct acpi_thermal *tz)
+{
+	acpi_status		status = AE_OK;
+	int			i = 0;
+
+	ACPI_FUNCTION_TRACE("acpi_thermal_get_trip_points");
+
+	if (!tz)
+		return_VALUE(-EINVAL);
+
+	/* Critical Shutdown (required) */
+
+	status = acpi_evaluate_integer(tz->handle, "_CRT", NULL, 
+		&tz->trips.critical.temperature);
+	if (ACPI_FAILURE(status)) {
+		tz->trips.critical.flags.valid = 0;
+		ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "No critical threshold\n"));
+		return -ENODEV;
+	}
+	else {
+		tz->trips.critical.flags.valid = 1;
+		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found critical threshold [%lu]\n", tz->trips.critical.temperature));
+	}
+
+	/* Critical Sleep (optional) */
+
+	status = acpi_evaluate_integer(tz->handle, "_HOT", NULL, &tz->trips.hot.temperature);
+	if (ACPI_FAILURE(status)) {
+		tz->trips.hot.flags.valid = 0;
+		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No hot threshold\n"));
+	}
+	else {
+		tz->trips.hot.flags.valid = 1;
+		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found hot threshold [%lu]\n", tz->trips.hot.temperature));
+	}
+
+	/* Passive: Processors (optional) */
+
+	status = acpi_evaluate_integer(tz->handle, "_PSV", NULL, &tz->trips.passive.temperature);
+	if (ACPI_FAILURE(status)) {
+		tz->trips.passive.flags.valid = 0;
+		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No passive threshold\n"));
+	}
+	else {
+		tz->trips.passive.flags.valid = 1;
+
+		status = acpi_evaluate_integer(tz->handle, "_TC1", NULL, &tz->trips.passive.tc1);
+		if (ACPI_FAILURE(status))
+			tz->trips.passive.flags.valid = 0;
+
+		status = acpi_evaluate_integer(tz->handle, "_TC2", NULL, &tz->trips.passive.tc2);
+		if (ACPI_FAILURE(status))
+			tz->trips.passive.flags.valid = 0;
+
+		status = acpi_evaluate_integer(tz->handle, "_TSP", NULL, &tz->trips.passive.tsp);
+		if (ACPI_FAILURE(status))
+			tz->trips.passive.flags.valid = 0;
+
+		status = acpi_evaluate_reference(tz->handle, "_PSL", NULL, &tz->trips.passive.devices);
+		if (ACPI_FAILURE(status))
+			tz->trips.passive.flags.valid = 0;
+
+		if (!tz->trips.passive.flags.valid)
+			ACPI_DEBUG_PRINT((ACPI_DB_WARN, "Invalid passive threshold\n"));
+		else
+			ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found passive threshold [%lu]\n", tz->trips.passive.temperature));
+	}
+
+	/* Active: Fans, etc. (optional) */
+
+	for (i=0; i<ACPI_THERMAL_MAX_ACTIVE; i++) {
+
+		char name[5] = {'_','A','C',('0'+i),'\0'};
+
+		status = acpi_evaluate_integer(tz->handle, name, NULL, &tz->trips.active[i].temperature);
+		if (ACPI_FAILURE(status))
+			break;
+
+		name[2] = 'L';
+		status = acpi_evaluate_reference(tz->handle, name, NULL, &tz->trips.active[i].devices);
+		if (ACPI_SUCCESS(status)) {
+			tz->trips.active[i].flags.valid = 1;
+			ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found active threshold [%d]:[%lu]\n", i, tz->trips.active[i].temperature));
+		}
+		else
+			ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid active threshold [%d]\n", i));
+	}
+
+	return_VALUE(0);
+}
+
+
+static int
+acpi_thermal_get_devices (
+	struct acpi_thermal	*tz)
+{
+	acpi_status		status = AE_OK;
+
+	ACPI_FUNCTION_TRACE("acpi_thermal_get_devices");
+
+	if (!tz)
+		return_VALUE(-EINVAL);
+
+	status = acpi_evaluate_reference(tz->handle, "_TZD", NULL, &tz->devices);
+	if (ACPI_FAILURE(status))
+		return_VALUE(-ENODEV);
+
+	return_VALUE(0);
+}
+
+
+static int
+acpi_thermal_call_usermode (
+	char			*path)
+{
+	char			*argv[2] = {NULL, NULL};
+	char			*envp[3] = {NULL, NULL, NULL};
+
+	ACPI_FUNCTION_TRACE("acpi_thermal_call_usermode");
+
+	if (!path)
+		return_VALUE(-EINVAL);
+
+	argv[0] = path;
+
+	/* minimal command environment */
+	envp[0] = "HOME=/";
+	envp[1] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin";
+	
+	call_usermodehelper(argv[0], argv, envp);
+
+	return_VALUE(0);
+}
+
+
+static int
+acpi_thermal_critical (
+	struct acpi_thermal	*tz)
+{
+	int			result = 0;
+	struct acpi_device	*device = NULL;
+
+	ACPI_FUNCTION_TRACE("acpi_thermal_critical");
+
+	if (!tz || !tz->trips.critical.flags.valid)
+		return_VALUE(-EINVAL);
+
+	if (tz->temperature >= tz->trips.critical.temperature) {
+		ACPI_DEBUG_PRINT((ACPI_DB_WARN, "Critical trip point\n"));
+		tz->trips.critical.flags.enabled = 1;
+	}
+	else if (tz->trips.critical.flags.enabled)
+		tz->trips.critical.flags.enabled = 0;
+
+	result = acpi_bus_get_device(tz->handle, &device);
+	if (result)
+		return_VALUE(result);
+
+	acpi_bus_generate_event(device, ACPI_THERMAL_NOTIFY_CRITICAL, tz->trips.critical.flags.enabled);
+
+	acpi_thermal_call_usermode(ACPI_THERMAL_PATH_POWEROFF);
+
+	return_VALUE(0);
+}
+
+
+static int
+acpi_thermal_hot (
+	struct acpi_thermal	*tz)
+{
+	int			result = 0;
+	struct acpi_device	*device = NULL;
+
+	ACPI_FUNCTION_TRACE("acpi_thermal_hot");
+
+	if (!tz || !tz->trips.hot.flags.valid)
+		return_VALUE(-EINVAL);
+
+	if (tz->temperature >= tz->trips.hot.temperature) {
+		ACPI_DEBUG_PRINT((ACPI_DB_WARN, "Hot trip point\n"));
+		tz->trips.hot.flags.enabled = 1;
+	}
+	else if (tz->trips.hot.flags.enabled)
+		tz->trips.hot.flags.enabled = 0;
+
+	result = acpi_bus_get_device(tz->handle, &device);
+	if (result)
+		return_VALUE(result);
+
+	acpi_bus_generate_event(device, ACPI_THERMAL_NOTIFY_HOT, tz->trips.hot.flags.enabled);
+
+	/* TBD: Call user-mode "sleep(S4)" function */
+
+	return_VALUE(0);
+}
+
+
+static int
+acpi_thermal_passive (
+	struct acpi_thermal	*tz)
+{
+	int			result = 0;
+	struct acpi_thermal_passive *passive = NULL;
+	int			trend = 0;
+	int			i = 0;
+
+	ACPI_FUNCTION_TRACE("acpi_thermal_passive");
+
+	if (!tz || !tz->trips.passive.flags.valid)
+		return_VALUE(-EINVAL);
+
+	passive = &(tz->trips.passive);
+
+	/*
+	 * Above Trip?
+	 * -----------
+	 * Calculate the thermal trend (using the passive cooling equation)
+	 * and modify the performance limit for all passive cooling devices
+	 * accordingly.  Note that we assume symmetry.
+	 */
+	if (tz->temperature >= passive->temperature) {
+		trend = (passive->tc1 * (tz->temperature - tz->last_temperature)) + (passive->tc2 * (tz->temperature - passive->temperature));
+		ACPI_DEBUG_PRINT((ACPI_DB_INFO, 
+			"trend[%d]=(tc1[%lu]*(tmp[%lu]-last[%lu]))+(tc2[%lu]*(tmp[%lu]-psv[%lu]))\n", 
+			trend, passive->tc1, tz->temperature, 
+			tz->last_temperature, passive->tc2, 
+			tz->temperature, passive->temperature));
+		tz->trips.passive.flags.enabled = 1;
+		/* Heating up? */
+		if (trend > 0)
+			for (i=0; i<passive->devices.count; i++)
+				acpi_processor_set_thermal_limit(
+					passive->devices.handles[i], 
+					ACPI_PROCESSOR_LIMIT_INCREMENT);
+		/* Cooling off? */
+		else if (trend < 0)
+			for (i=0; i<passive->devices.count; i++)
+				acpi_processor_set_thermal_limit(
+					passive->devices.handles[i], 
+					ACPI_PROCESSOR_LIMIT_DECREMENT);
+	}
+
+	/*
+	 * Below Trip?
+	 * -----------
+	 * Implement passive cooling hysteresis to slowly increase performance
+	 * and avoid thrashing around the passive trip point.  Note that we
+	 * assume symmetry.
+	 */
+	else if (tz->trips.passive.flags.enabled) {
+		for (i=0; i<passive->devices.count; i++)
+			result = acpi_processor_set_thermal_limit(
+				passive->devices.handles[i], 
+				ACPI_PROCESSOR_LIMIT_DECREMENT);
+		if (result == 1) {
+			tz->trips.passive.flags.enabled = 0;
+			ACPI_DEBUG_PRINT((ACPI_DB_INFO, 
+				"Disabling passive cooling (zone is cool)\n"));
+		}
+	}
+
+	return_VALUE(0);
+}
+
+
+static int
+acpi_thermal_active (
+	struct acpi_thermal	*tz)
+{
+	int			result = 0;
+	struct acpi_thermal_active *active = NULL;
+	int                     i = 0;
+	int			j = 0;
+	unsigned long		maxtemp = 0;
+
+	ACPI_FUNCTION_TRACE("acpi_thermal_active");
+
+	if (!tz)
+		return_VALUE(-EINVAL);
+
+	for (i=0; i<ACPI_THERMAL_MAX_ACTIVE; i++) {
+
+		active = &(tz->trips.active[i]);
+		if (!active || !active->flags.valid)
+			break;
+
+		/*
+		 * Above Threshold?
+		 * ----------------
+		 * If not already enabled, turn ON all cooling devices
+		 * associated with this active threshold.
+		 */
+		if (tz->temperature >= active->temperature) {
+			if (active->temperature > maxtemp)
+				tz->state.active_index = i, maxtemp = active->temperature;
+			if (!active->flags.enabled) {
+				for (j = 0; j < active->devices.count; j++) {
+					result = acpi_bus_set_power(active->devices.handles[j], ACPI_STATE_D0);
+					if (result) {
+						ACPI_DEBUG_PRINT((ACPI_DB_WARN, "Unable to turn cooling device [%p] 'on'\n", active->devices.handles[j]));
+						continue;
+					}
+					active->flags.enabled = 1;
+					ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Cooling device [%p] now 'on'\n", active->devices.handles[j]));
+				}
+			}
+		}
+		/*
+		 * Below Threshold?
+		 * ----------------
+		 * Turn OFF all cooling devices associated with this
+		 * threshold.
+		 */
+		else if (active->flags.enabled) {
+			for (j = 0; j < active->devices.count; j++) {
+				result = acpi_bus_set_power(active->devices.handles[j], ACPI_STATE_D3);
+				if (result) {
+					ACPI_DEBUG_PRINT((ACPI_DB_WARN, "Unable to turn cooling device [%p] 'off'\n", active->devices.handles[j]));
+					continue;
+				}
+				active->flags.enabled = 0;
+				ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Cooling device [%p] now 'off'\n", active->devices.handles[j]));
+			}
+		}
+	}
+
+	return_VALUE(0);
+}
+
+
+static void acpi_thermal_check (void *context);
+
+static void
+acpi_thermal_run (
+	unsigned long		data)
+{
+	acpi_os_queue_for_execution(OSD_PRIORITY_GPE,  acpi_thermal_check, (void *) data);
+}
+
+
+static void
+acpi_thermal_check (
+	void                    *data)
+{
+	int			result = 0;
+	struct acpi_thermal	*tz = (struct acpi_thermal *) data;
+	unsigned long		sleep_time = 0;
+	int			i = 0;
+	struct acpi_thermal_state state = tz->state;
+
+	ACPI_FUNCTION_TRACE("acpi_thermal_check");
+
+	if (!tz) {
+		ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid (NULL) context.\n"));
+		return_VOID;
+	}
+
+	result = acpi_thermal_get_temperature(tz);
+	if (result)
+		return_VOID;
+	
+	memset(&tz->state, 0, sizeof(tz->state));
+	
+	/*
+	 * Check Trip Points
+	 * -----------------
+	 * Compare the current temperature to the trip point values to see
+	 * if we've entered one of the thermal policy states.  Note that
+	 * this function determines when a state is entered, but the 
+	 * individual policy decides when it is exited (e.g. hysteresis).
+	 */
+	if (tz->trips.critical.flags.valid)
+		state.critical |= (tz->temperature >= tz->trips.critical.temperature);
+	if (tz->trips.hot.flags.valid)
+		state.hot |= (tz->temperature >= tz->trips.hot.temperature);
+	if (tz->trips.passive.flags.valid)
+		state.passive |= (tz->temperature >= tz->trips.passive.temperature);
+	for (i=0; i<ACPI_THERMAL_MAX_ACTIVE; i++)
+		if (tz->trips.active[i].flags.valid)
+			state.active |= (tz->temperature >= tz->trips.active[i].temperature);
+
+	/*
+	 * Invoke Policy
+	 * -------------
+	 * Separated from the above check to allow individual policy to 
+	 * determine when to exit a given state.
+	 */
+	if (state.critical)
+		acpi_thermal_critical(tz);
+	if (state.hot)
+		acpi_thermal_hot(tz);
+	if (state.passive)
+		acpi_thermal_passive(tz);
+	if (state.active)
+		acpi_thermal_active(tz);
+
+	/*
+	 * Calculate State
+	 * ---------------
+	 * Again, separated from the above two to allow independent policy
+	 * decisions.
+	 */
+	if (tz->trips.critical.flags.enabled)
+		tz->state.critical = 1;
+	if (tz->trips.hot.flags.enabled)
+		tz->state.hot = 1;
+	if (tz->trips.passive.flags.enabled)
+		tz->state.passive = 1;
+	for (i=0; i<ACPI_THERMAL_MAX_ACTIVE; i++)
+		if (tz->trips.active[i].flags.enabled)
+			tz->state.active = 1;
+
+	/*
+	 * Calculate Sleep Time
+	 * --------------------
+	 * If we're in the passive state, use _TSP's value.  Otherwise
+	 * use the default polling frequency (e.g. _TZP).  If no polling
+	 * frequency is specified then we'll wait forever (at least until
+	 * a thermal event occurs).  Note that _TSP and _TZD values are
+	 * given in 1/10th seconds (we must covert to milliseconds).
+	 */
+	if (tz->state.passive)
+		sleep_time = tz->trips.passive.tsp * 100;
+	else if (tz->polling_frequency > 0)
+		sleep_time = tz->polling_frequency * 100;
+
+	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "%s: temperature[%lu] sleep[%lu]\n", 
+		tz->name, tz->temperature, sleep_time));
+
+	/*
+	 * Schedule Next Poll
+	 * ------------------
+	 */
+	if (!sleep_time) {
+		if (timer_pending(&(tz->timer)))
+			del_timer(&(tz->timer));
+	}
+	else {
+		if (timer_pending(&(tz->timer)))
+			mod_timer(&(tz->timer), (HZ * sleep_time) / 1000);
+		else {
+			tz->timer.data = (unsigned long) tz;
+			tz->timer.function = acpi_thermal_run;
+			tz->timer.expires = jiffies + (HZ * sleep_time) / 1000;
+			add_timer(&(tz->timer));
+		}
+	}
+
+	return_VOID;
+}
+
+
+/* --------------------------------------------------------------------------
+                              FS Interface (/proc)
+   -------------------------------------------------------------------------- */
+
+struct proc_dir_entry		*acpi_thermal_dir = NULL;
+
+
+static int
+acpi_thermal_read_state (
+	char			*page,
+	char			**start,
+	off_t			off,
+	int 			count,
+	int 			*eof,
+	void			*data)
+{
+	struct acpi_thermal	*tz = (struct acpi_thermal *) data;
+	char			*p = page;
+	int			len = 0;
+
+	ACPI_FUNCTION_TRACE("acpi_thermal_read_state");
+
+	if (!tz || (off != 0))
+		goto end;
+
+	p += sprintf(p, "state:                   ");
+
+	if (!tz->state.critical && !tz->state.hot && !tz->state.passive && !tz->state.active)
+		p += sprintf(p, "ok\n");
+	else {
+		if (tz->state.critical)
+			p += sprintf(p, "critical ");
+		if (tz->state.hot)
+			p += sprintf(p, "hot ");
+		if (tz->state.passive)
+			p += sprintf(p, "passive ");
+		if (tz->state.active)
+			p += sprintf(p, "active[%d]", tz->state.active_index);
+		p += sprintf(p, "\n");
+	}
+
+end:
+	len = (p - page);
+	if (len <= off+count) *eof = 1;
+	*start = page + off;
+	len -= off;
+	if (len>count) len = count;
+	if (len<0) len = 0;
+
+	return_VALUE(len);
+}
+
+
+static int
+acpi_thermal_read_temperature (
+	char			*page,
+	char			**start,
+	off_t			off,
+	int 			count,
+	int 			*eof,
+	void			*data)
+{
+	int			result = 0;
+	struct acpi_thermal	*tz = (struct acpi_thermal *) data;
+	char			*p = page;
+	int			len = 0;
+
+	ACPI_FUNCTION_TRACE("acpi_thermal_read_temperature");
+
+	if (!tz || (off != 0))
+		goto end;
+
+	result = acpi_thermal_get_temperature(tz);
+	if (result)
+		goto end;
+
+	p += sprintf(p, "temperature:             %ld C\n", 
+		KELVIN_TO_CELSIUS(tz->temperature));
+	
+end:
+	len = (p - page);
+	if (len <= off+count) *eof = 1;
+	*start = page + off;
+	len -= off;
+	if (len>count) len = count;
+	if (len<0) len = 0;
+
+	return_VALUE(len);
+}
+
+
+static int
+acpi_thermal_read_trip_points (
+	char			*page,
+	char			**start,
+	off_t			off,
+	int 			count,
+	int 			*eof,
+	void			*data)
+{
+	struct acpi_thermal	*tz = (struct acpi_thermal *) data;
+	char			*p = page;
+	int			len = 0;
+	int			i = 0;
+	int			j = 0;
+
+	ACPI_FUNCTION_TRACE("acpi_thermal_read_trip_points");
+
+	if (!tz || (off != 0))
+		goto end;
+
+	if (tz->trips.critical.flags.valid)
+		p += sprintf(p, "critical (S5):           %ld C\n",
+			KELVIN_TO_CELSIUS(tz->trips.critical.temperature));
+
+	if (tz->trips.hot.flags.valid)
+		p += sprintf(p, "hot (S4):                %ld C\n",
+			KELVIN_TO_CELSIUS(tz->trips.hot.temperature));
+
+	if (tz->trips.passive.flags.valid) {
+		p += sprintf(p, "passive:                 %ld C: tc1=%lu tc2=%lu tsp=%lu devices=",
+			KELVIN_TO_CELSIUS(tz->trips.passive.temperature),
+			tz->trips.passive.tc1,
+			tz->trips.passive.tc2, 
+			tz->trips.passive.tsp);
+		for (j=0; j<tz->trips.passive.devices.count; j++) {
+
+			p += sprintf(p, "0x%p ", tz->trips.passive.devices.handles[j]);
+		}
+		p += sprintf(p, "\n");
+	}
+
+	for (i=0; i<ACPI_THERMAL_MAX_ACTIVE; i++) {
+		if (!(tz->trips.active[i].flags.valid))
+			break;
+		p += sprintf(p, "active[%d]:               %ld C: devices=",
+			i, KELVIN_TO_CELSIUS(tz->trips.active[i].temperature));
+		for (j=0; j<tz->trips.active[i].devices.count; j++) 
+			p += sprintf(p, "0x%p ",
+				tz->trips.active[i].devices.handles[j]);
+		p += sprintf(p, "\n");
+	}
+
+end:
+	len = (p - page);
+	if (len <= off+count) *eof = 1;
+	*start = page + off;
+	len -= off;
+	if (len>count) len = count;
+	if (len<0) len = 0;
+
+	return_VALUE(len);
+}
+
+
+static int
+acpi_thermal_write_trip_points (
+        struct file		*file,
+        const char		*buffer,
+        unsigned long		count,
+        void			*data)
+{
+	struct acpi_thermal	*tz = (struct acpi_thermal *) data;
+	char			limit_string[25] = {'\0'};
+	int			critical, hot, passive, active0, active1;
+
+	ACPI_FUNCTION_TRACE("acpi_thermal_write_trip_points");
+
+	if (!tz || (count > sizeof(limit_string) - 1)) {
+		ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid argument\n"));
+		return_VALUE(-EINVAL);
+	}
+	
+	if (copy_from_user(limit_string, buffer, count)) {
+		ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid data\n"));
+		return_VALUE(-EFAULT);
+	}
+	
+	limit_string[count] = '\0';
+
+	if (sscanf(limit_string, "%d:%d:%d:%d:%d", &critical, &hot, &passive, &active0, &active1) != 5) {
+		ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid data format\n"));
+		return_VALUE(-EINVAL);
+	}
+
+	tz->trips.critical.temperature = CELSIUS_TO_KELVIN(critical);
+	tz->trips.hot.temperature = CELSIUS_TO_KELVIN(hot);
+	tz->trips.passive.temperature = CELSIUS_TO_KELVIN(passive);
+	tz->trips.active[0].temperature = CELSIUS_TO_KELVIN(active0);
+	tz->trips.active[1].temperature = CELSIUS_TO_KELVIN(active1);
+	
+	return_VALUE(count);
+}
+
+
+static int
+acpi_thermal_read_cooling_mode (
+	char			*page,
+	char			**start,
+	off_t			off,
+	int 			count,
+	int 			*eof,
+	void			*data)
+{
+	struct acpi_thermal	*tz = (struct acpi_thermal *) data;
+	char			*p = page;
+	int			len = 0;
+
+	ACPI_FUNCTION_TRACE("acpi_thermal_read_cooling_mode");
+
+	if (!tz || (off != 0))
+		goto end;
+
+	if (!tz->flags.cooling_mode) {
+		p += sprintf(p, "<not supported>\n");
+		goto end;
+	}
+
+	p += sprintf(p, "cooling mode:            %s\n",
+		tz->cooling_mode?"passive":"active");
+
+end:
+	len = (p - page);
+	if (len <= off+count) *eof = 1;
+	*start = page + off;
+	len -= off;
+	if (len>count) len = count;
+	if (len<0) len = 0;
+
+	return_VALUE(len);
+}
+
+
+static int
+acpi_thermal_write_cooling_mode (
+	struct file		*file,
+	const char		*buffer,
+	unsigned long		count,
+	void			*data)
+{
+	int			result = 0;
+	struct acpi_thermal	*tz = (struct acpi_thermal *) data;
+	char			mode_string[12] = {'\0'};
+
+	ACPI_FUNCTION_TRACE("acpi_thermal_write_cooling_mode");
+
+	if (!tz || (count > sizeof(mode_string) - 1))
+		return_VALUE(-EINVAL);
+
+	if (!tz->flags.cooling_mode)
+		return_VALUE(-ENODEV);
+
+	if (copy_from_user(mode_string, buffer, count))
+		return_VALUE(-EFAULT);
+	
+	mode_string[count] = '\0';
+	
+	result = acpi_thermal_set_cooling_mode(tz, 
+		simple_strtoul(mode_string, NULL, 0));
+	if (result)
+		return_VALUE(result);
+
+	return_VALUE(count);
+}
+
+
+static int
+acpi_thermal_read_polling (
+	char			*page,
+	char			**start,
+	off_t			off,
+	int 			count,
+	int 			*eof,
+	void			*data)
+{
+	struct acpi_thermal	*tz = (struct acpi_thermal *) data;
+	char			*p = page;
+	int			len = 0;
+
+	ACPI_FUNCTION_TRACE("acpi_thermal_read_polling");
+
+	if (!tz || (off != 0))
+		goto end;
+
+	if (!tz->polling_frequency) {
+		p += sprintf(p, "<polling disabled>\n");
+		goto end;
+	}
+
+	p += sprintf(p, "polling frequency:       %lu seconds\n",
+		(tz->polling_frequency / 10));
+
+end:
+	len = (p - page);
+	if (len <= off+count) *eof = 1;
+	*start = page + off;
+	len -= off;
+	if (len>count) len = count;
+	if (len<0) len = 0;
+
+	return_VALUE(len);
+}
+
+
+static int
+acpi_thermal_write_polling (
+	struct file		*file,
+	const char		*buffer,
+	unsigned long		count,
+	void			*data)
+{
+	int			result = 0;
+	struct acpi_thermal	*tz = (struct acpi_thermal *) data;
+	char			polling_string[12] = {'\0'};
+	int			seconds = 0;
+
+	ACPI_FUNCTION_TRACE("acpi_thermal_write_polling");
+
+	if (!tz || (count > sizeof(polling_string) - 1))
+		return_VALUE(-EINVAL);
+	
+	if (copy_from_user(polling_string, buffer, count))
+		return_VALUE(-EFAULT);
+	
+	polling_string[count] = '\0';
+
+	seconds = simple_strtoul(polling_string, NULL, 0);
+	
+	result = acpi_thermal_set_polling(tz, seconds);
+	if (result)
+		return_VALUE(result);
+
+	acpi_thermal_check(tz);
+
+	return_VALUE(count);
+}
+
+
+static int
+acpi_thermal_add_fs (
+	struct acpi_device	*device)
+{
+	struct proc_dir_entry	*entry = NULL;
+
+	ACPI_FUNCTION_TRACE("acpi_thermal_add_fs");
+
+	if (!acpi_device_dir(device)) {
+		acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
+			acpi_thermal_dir);
+		if (!acpi_device_dir(device))
+			return_VALUE(-ENODEV);
+	}
+
+	/* 'state' [R] */
+	entry = create_proc_entry(ACPI_THERMAL_FILE_STATE,
+		S_IRUGO, acpi_device_dir(device));
+	if (!entry)
+		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
+			"Unable to create '%s' fs entry\n",
+			ACPI_THERMAL_FILE_STATE));
+	else {
+		entry->read_proc = acpi_thermal_read_state;
+		entry->data = acpi_driver_data(device);
+	}
+
+	/* 'temperature' [R] */
+	entry = create_proc_entry(ACPI_THERMAL_FILE_TEMPERATURE,
+		S_IRUGO, acpi_device_dir(device));
+	if (!entry)
+		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
+			"Unable to create '%s' fs entry\n",
+			ACPI_THERMAL_FILE_TEMPERATURE));
+	else {
+		entry->read_proc = acpi_thermal_read_temperature;
+		entry->data = acpi_driver_data(device);
+	}
+
+	/* 'trip_points' [R/W] */
+	entry = create_proc_entry(ACPI_THERMAL_FILE_TRIP_POINTS,
+		S_IFREG|S_IRUGO|S_IWUSR, acpi_device_dir(device));
+	if (!entry)
+		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
+			"Unable to create '%s' fs entry\n",
+			ACPI_THERMAL_FILE_POLLING_FREQ));
+	else {
+		entry->read_proc = acpi_thermal_read_trip_points;
+		entry->write_proc = acpi_thermal_write_trip_points;
+		entry->data = acpi_driver_data(device);
+	}
+
+	/* 'cooling_mode' [R/W] */
+	entry = create_proc_entry(ACPI_THERMAL_FILE_COOLING_MODE,
+		S_IFREG|S_IRUGO|S_IWUSR, acpi_device_dir(device));
+	if (!entry)
+		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
+			"Unable to create '%s' fs entry\n",
+			ACPI_THERMAL_FILE_COOLING_MODE));
+	else {
+		entry->read_proc = acpi_thermal_read_cooling_mode;
+		entry->write_proc = acpi_thermal_write_cooling_mode;
+		entry->data = acpi_driver_data(device);
+	}
+
+	/* 'polling_frequency' [R/W] */
+	entry = create_proc_entry(ACPI_THERMAL_FILE_POLLING_FREQ,
+		S_IFREG|S_IRUGO|S_IWUSR, acpi_device_dir(device));
+	if (!entry)
+		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
+			"Unable to create '%s' fs entry\n",
+			ACPI_THERMAL_FILE_POLLING_FREQ));
+	else {
+		entry->read_proc = acpi_thermal_read_polling;
+		entry->write_proc = acpi_thermal_write_polling;
+		entry->data = acpi_driver_data(device);
+	}
+
+	return_VALUE(0);
+}
+
+
+static int
+acpi_thermal_remove_fs (
+	struct acpi_device	*device)
+{
+	ACPI_FUNCTION_TRACE("acpi_thermal_remove_fs");
+
+	if (acpi_device_dir(device)) {
+		remove_proc_entry(acpi_device_bid(device), acpi_thermal_dir);
+		acpi_device_dir(device) = NULL;
+	}
+
+	return_VALUE(0);
+}
+
+
+/* --------------------------------------------------------------------------
+                                 Driver Interface
+   -------------------------------------------------------------------------- */
+
+static void
+acpi_thermal_notify (
+	acpi_handle 		handle,
+	u32 			event,
+	void 			*data)
+{
+	struct acpi_thermal	*tz = (struct acpi_thermal *) data;
+	struct acpi_device	*device = NULL;
+
+	ACPI_FUNCTION_TRACE("acpi_thermal_notify");
+
+	if (!tz)
+		return_VOID;
+
+	if (acpi_bus_get_device(tz->handle, &device))
+		return_VOID;
+
+	switch (event) {
+	case ACPI_THERMAL_NOTIFY_TEMPERATURE:
+		acpi_thermal_check(tz);
+		break;
+	case ACPI_THERMAL_NOTIFY_THRESHOLDS:
+		acpi_thermal_get_trip_points(tz);
+		acpi_thermal_check(tz);
+		acpi_bus_generate_event(device, event, 0);
+		break;
+	case ACPI_THERMAL_NOTIFY_DEVICES:
+		if (tz->flags.devices)
+			acpi_thermal_get_devices(tz);
+		acpi_bus_generate_event(device, event, 0);
+		break;
+	default:
+		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+			"Unsupported event [0x%x]\n", event));
+		break;
+	}
+
+	return_VOID;
+}
+
+
+static int
+acpi_thermal_get_info (
+	struct acpi_thermal	*tz)
+{
+	int			result = 0;
+
+	ACPI_FUNCTION_TRACE("acpi_thermal_get_info");
+
+	if (!tz)
+		return_VALUE(-EINVAL);
+
+	/* Get temperature [_TMP] (required) */
+	result = acpi_thermal_get_temperature(tz);
+	if (result)
+		return_VALUE(result);
+
+	/* Set the cooling mode [_SCP] to active cooling (default) */
+	result = acpi_thermal_set_cooling_mode(tz, ACPI_THERMAL_MODE_ACTIVE);
+	if (!result)
+		tz->flags.cooling_mode = 1;
+
+	/* Get trip points [_CRT, _PSV, etc.] (required) */
+	result = acpi_thermal_get_trip_points(tz);
+	if (result)
+		return_VALUE(result);
+
+	/* Get default polling frequency [_TZP] (optional) */
+	if (tzp)
+		tz->polling_frequency = tzp;
+	else
+		acpi_thermal_get_polling_frequency(tz);
+
+	/* Get devices in this thermal zone [_TZD] (optional) */
+	result = acpi_thermal_get_devices(tz);
+	if (!result)
+		tz->flags.devices = 1;
+
+	return_VALUE(0);
+}
+
+
+static int
+acpi_thermal_add (
+	struct acpi_device 		*device)
+{
+	int			result = 0;
+	acpi_status		status = AE_OK;
+	struct acpi_thermal	*tz = NULL;
+
+	ACPI_FUNCTION_TRACE("acpi_thermal_add");
+
+	if (!device)
+		return_VALUE(-EINVAL);
+
+	tz = kmalloc(sizeof(struct acpi_thermal), GFP_KERNEL);
+	if (!tz)
+		return_VALUE(-ENOMEM);
+	memset(tz, 0, sizeof(struct acpi_thermal));
+
+	tz->handle = device->handle;
+	sprintf(tz->name, "%s", device->pnp.bus_id);
+	sprintf(acpi_device_name(device), "%s", ACPI_THERMAL_DEVICE_NAME);
+	sprintf(acpi_device_class(device), "%s", ACPI_THERMAL_CLASS);
+	acpi_driver_data(device) = tz;
+
+	result = acpi_thermal_get_info(tz);
+	if (result)
+		goto end;
+
+	result = acpi_thermal_add_fs(device);
+	if (result)
+		return_VALUE(result);
+
+	init_timer(&tz->timer);
+
+	acpi_thermal_check(tz);
+
+	status = acpi_install_notify_handler(tz->handle,
+		ACPI_DEVICE_NOTIFY, acpi_thermal_notify, tz);
+	if (ACPI_FAILURE(status)) {
+		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
+			"Error installing notify handler\n"));
+		result = -ENODEV;
+		goto end;
+	}
+
+	printk(KERN_INFO PREFIX "%s [%s] (%ld C)\n",
+		acpi_device_name(device), acpi_device_bid(device),
+		KELVIN_TO_CELSIUS(tz->temperature));
+
+end:
+	if (result) {
+		acpi_thermal_remove_fs(device);
+		kfree(tz);
+	}
+
+	return_VALUE(result);
+}
+
+
+static int
+acpi_thermal_remove (
+	struct acpi_device	*device,
+	int			type)
+{
+	acpi_status		status = AE_OK;
+	struct acpi_thermal	*tz = NULL;
+
+	ACPI_FUNCTION_TRACE("acpi_thermal_remove");
+
+	if (!device || !acpi_driver_data(device))
+		return_VALUE(-EINVAL);
+
+	tz = (struct acpi_thermal *) acpi_driver_data(device);
+
+	if (timer_pending(&(tz->timer)))
+		del_timer(&(tz->timer));
+
+	status = acpi_remove_notify_handler(tz->handle,
+		ACPI_DEVICE_NOTIFY, acpi_thermal_notify);
+	if (ACPI_FAILURE(status))
+		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
+			"Error removing notify handler\n"));
+
+	/* Terminate policy */
+	if (tz->trips.passive.flags.valid
+		&& tz->trips.passive.flags.enabled) {
+		tz->trips.passive.flags.enabled = 0;
+		acpi_thermal_passive(tz);
+	}
+	if (tz->trips.active[0].flags.valid
+		&& tz->trips.active[0].flags.enabled) {
+		tz->trips.active[0].flags.enabled = 0;
+		acpi_thermal_active(tz);
+	}
+
+	acpi_thermal_remove_fs(device);
+
+	return_VALUE(0);
+}
+
+
+static int __init
+acpi_thermal_init (void)
+{
+	int			result = 0;
+
+	ACPI_FUNCTION_TRACE("acpi_thermal_init");
+
+	acpi_thermal_dir = proc_mkdir(ACPI_THERMAL_CLASS, acpi_root_dir);
+	if (!acpi_thermal_dir)
+		return_VALUE(-ENODEV);
+
+	result = acpi_bus_register_driver(&acpi_thermal_driver);
+	if (result < 0) {
+		remove_proc_entry(ACPI_THERMAL_CLASS, acpi_root_dir);
+		return_VALUE(-ENODEV);
+	}
+
+	return_VALUE(0);
+}
+
+
+static void __exit
+acpi_thermal_exit (void)
+{
+	ACPI_FUNCTION_TRACE("acpi_thermal_exit");
+
+	acpi_bus_unregister_driver(&acpi_thermal_driver);
+
+	remove_proc_entry(ACPI_THERMAL_CLASS, acpi_root_dir);
+
+	return_VOID;
+}
+
+
+module_init(acpi_thermal_init);
+module_exit(acpi_thermal_exit);
FUNET's LINUX-ADM group, linux-adm@nic.funet.fi
TCL-scripts by Sam Shen (who was at: slshen@lbl.gov)