xref: /linux/drivers/acpi/thermal.c (revision b9ccfda293ee6fca9a89a1584f0900e0627b975e)
1 /*
2  *  acpi_thermal.c - ACPI Thermal Zone Driver ($Revision: 41 $)
3  *
4  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
5  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
6  *
7  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
8  *
9  *  This program is free software; you can redistribute it and/or modify
10  *  it under the terms of the GNU General Public License as published by
11  *  the Free Software Foundation; either version 2 of the License, or (at
12  *  your option) any later version.
13  *
14  *  This program is distributed in the hope that it will be useful, but
15  *  WITHOUT ANY WARRANTY; without even the implied warranty of
16  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17  *  General Public License for more details.
18  *
19  *  You should have received a copy of the GNU General Public License along
20  *  with this program; if not, write to the Free Software Foundation, Inc.,
21  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
22  *
23  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
24  *
25  *  This driver fully implements the ACPI thermal policy as described in the
26  *  ACPI 2.0 Specification.
27  *
28  *  TBD: 1. Implement passive cooling hysteresis.
29  *       2. Enhance passive cooling (CPU) states/limit interface to support
30  *          concepts of 'multiple limiters', upper/lower limits, etc.
31  *
32  */
33 
34 #include <linux/kernel.h>
35 #include <linux/module.h>
36 #include <linux/dmi.h>
37 #include <linux/init.h>
38 #include <linux/slab.h>
39 #include <linux/types.h>
40 #include <linux/jiffies.h>
41 #include <linux/kmod.h>
42 #include <linux/reboot.h>
43 #include <linux/device.h>
44 #include <asm/uaccess.h>
45 #include <linux/thermal.h>
46 #include <acpi/acpi_bus.h>
47 #include <acpi/acpi_drivers.h>
48 
49 #define PREFIX "ACPI: "
50 
51 #define ACPI_THERMAL_CLASS		"thermal_zone"
52 #define ACPI_THERMAL_DEVICE_NAME	"Thermal Zone"
53 #define ACPI_THERMAL_FILE_STATE		"state"
54 #define ACPI_THERMAL_FILE_TEMPERATURE	"temperature"
55 #define ACPI_THERMAL_FILE_TRIP_POINTS	"trip_points"
56 #define ACPI_THERMAL_FILE_COOLING_MODE	"cooling_mode"
57 #define ACPI_THERMAL_FILE_POLLING_FREQ	"polling_frequency"
58 #define ACPI_THERMAL_NOTIFY_TEMPERATURE	0x80
59 #define ACPI_THERMAL_NOTIFY_THRESHOLDS	0x81
60 #define ACPI_THERMAL_NOTIFY_DEVICES	0x82
61 #define ACPI_THERMAL_NOTIFY_CRITICAL	0xF0
62 #define ACPI_THERMAL_NOTIFY_HOT		0xF1
63 #define ACPI_THERMAL_MODE_ACTIVE	0x00
64 
65 #define ACPI_THERMAL_MAX_ACTIVE	10
66 #define ACPI_THERMAL_MAX_LIMIT_STR_LEN 65
67 
68 #define _COMPONENT		ACPI_THERMAL_COMPONENT
69 ACPI_MODULE_NAME("thermal");
70 
71 MODULE_AUTHOR("Paul Diefenbaugh");
72 MODULE_DESCRIPTION("ACPI Thermal Zone Driver");
73 MODULE_LICENSE("GPL");
74 
75 static int act;
76 module_param(act, int, 0644);
77 MODULE_PARM_DESC(act, "Disable or override all lowest active trip points.");
78 
79 static int crt;
80 module_param(crt, int, 0644);
81 MODULE_PARM_DESC(crt, "Disable or lower all critical trip points.");
82 
83 static int tzp;
84 module_param(tzp, int, 0444);
85 MODULE_PARM_DESC(tzp, "Thermal zone polling frequency, in 1/10 seconds.");
86 
87 static int nocrt;
88 module_param(nocrt, int, 0);
89 MODULE_PARM_DESC(nocrt, "Set to take no action upon ACPI thermal zone critical trips points.");
90 
91 static int off;
92 module_param(off, int, 0);
93 MODULE_PARM_DESC(off, "Set to disable ACPI thermal support.");
94 
95 static int psv;
96 module_param(psv, int, 0644);
97 MODULE_PARM_DESC(psv, "Disable or override all passive trip points.");
98 
99 static int acpi_thermal_add(struct acpi_device *device);
100 static int acpi_thermal_remove(struct acpi_device *device, int type);
101 static void acpi_thermal_notify(struct acpi_device *device, u32 event);
102 
103 static const struct acpi_device_id  thermal_device_ids[] = {
104 	{ACPI_THERMAL_HID, 0},
105 	{"", 0},
106 };
107 MODULE_DEVICE_TABLE(acpi, thermal_device_ids);
108 
109 static int acpi_thermal_resume(struct device *dev);
110 static SIMPLE_DEV_PM_OPS(acpi_thermal_pm, NULL, acpi_thermal_resume);
111 
112 static struct acpi_driver acpi_thermal_driver = {
113 	.name = "thermal",
114 	.class = ACPI_THERMAL_CLASS,
115 	.ids = thermal_device_ids,
116 	.ops = {
117 		.add = acpi_thermal_add,
118 		.remove = acpi_thermal_remove,
119 		.notify = acpi_thermal_notify,
120 		},
121 	.drv.pm = &acpi_thermal_pm,
122 };
123 
124 struct acpi_thermal_state {
125 	u8 critical:1;
126 	u8 hot:1;
127 	u8 passive:1;
128 	u8 active:1;
129 	u8 reserved:4;
130 	int active_index;
131 };
132 
133 struct acpi_thermal_state_flags {
134 	u8 valid:1;
135 	u8 enabled:1;
136 	u8 reserved:6;
137 };
138 
139 struct acpi_thermal_critical {
140 	struct acpi_thermal_state_flags flags;
141 	unsigned long temperature;
142 };
143 
144 struct acpi_thermal_hot {
145 	struct acpi_thermal_state_flags flags;
146 	unsigned long temperature;
147 };
148 
149 struct acpi_thermal_passive {
150 	struct acpi_thermal_state_flags flags;
151 	unsigned long temperature;
152 	unsigned long tc1;
153 	unsigned long tc2;
154 	unsigned long tsp;
155 	struct acpi_handle_list devices;
156 };
157 
158 struct acpi_thermal_active {
159 	struct acpi_thermal_state_flags flags;
160 	unsigned long temperature;
161 	struct acpi_handle_list devices;
162 };
163 
164 struct acpi_thermal_trips {
165 	struct acpi_thermal_critical critical;
166 	struct acpi_thermal_hot hot;
167 	struct acpi_thermal_passive passive;
168 	struct acpi_thermal_active active[ACPI_THERMAL_MAX_ACTIVE];
169 };
170 
171 struct acpi_thermal_flags {
172 	u8 cooling_mode:1;	/* _SCP */
173 	u8 devices:1;		/* _TZD */
174 	u8 reserved:6;
175 };
176 
177 struct acpi_thermal {
178 	struct acpi_device * device;
179 	acpi_bus_id name;
180 	unsigned long temperature;
181 	unsigned long last_temperature;
182 	unsigned long polling_frequency;
183 	volatile u8 zombie;
184 	struct acpi_thermal_flags flags;
185 	struct acpi_thermal_state state;
186 	struct acpi_thermal_trips trips;
187 	struct acpi_handle_list devices;
188 	struct thermal_zone_device *thermal_zone;
189 	int tz_enabled;
190 	int kelvin_offset;
191 	struct mutex lock;
192 };
193 
194 /* --------------------------------------------------------------------------
195                              Thermal Zone Management
196    -------------------------------------------------------------------------- */
197 
198 static int acpi_thermal_get_temperature(struct acpi_thermal *tz)
199 {
200 	acpi_status status = AE_OK;
201 	unsigned long long tmp;
202 
203 	if (!tz)
204 		return -EINVAL;
205 
206 	tz->last_temperature = tz->temperature;
207 
208 	status = acpi_evaluate_integer(tz->device->handle, "_TMP", NULL, &tmp);
209 	if (ACPI_FAILURE(status))
210 		return -ENODEV;
211 
212 	tz->temperature = tmp;
213 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Temperature is %lu dK\n",
214 			  tz->temperature));
215 
216 	return 0;
217 }
218 
219 static int acpi_thermal_get_polling_frequency(struct acpi_thermal *tz)
220 {
221 	acpi_status status = AE_OK;
222 	unsigned long long tmp;
223 
224 	if (!tz)
225 		return -EINVAL;
226 
227 	status = acpi_evaluate_integer(tz->device->handle, "_TZP", NULL, &tmp);
228 	if (ACPI_FAILURE(status))
229 		return -ENODEV;
230 
231 	tz->polling_frequency = tmp;
232 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Polling frequency is %lu dS\n",
233 			  tz->polling_frequency));
234 
235 	return 0;
236 }
237 
238 static int acpi_thermal_set_cooling_mode(struct acpi_thermal *tz, int mode)
239 {
240 	acpi_status status = AE_OK;
241 	union acpi_object arg0 = { ACPI_TYPE_INTEGER };
242 	struct acpi_object_list arg_list = { 1, &arg0 };
243 	acpi_handle handle = NULL;
244 
245 
246 	if (!tz)
247 		return -EINVAL;
248 
249 	status = acpi_get_handle(tz->device->handle, "_SCP", &handle);
250 	if (ACPI_FAILURE(status)) {
251 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "_SCP not present\n"));
252 		return -ENODEV;
253 	}
254 
255 	arg0.integer.value = mode;
256 
257 	status = acpi_evaluate_object(handle, NULL, &arg_list, NULL);
258 	if (ACPI_FAILURE(status))
259 		return -ENODEV;
260 
261 	return 0;
262 }
263 
264 #define ACPI_TRIPS_CRITICAL	0x01
265 #define ACPI_TRIPS_HOT		0x02
266 #define ACPI_TRIPS_PASSIVE	0x04
267 #define ACPI_TRIPS_ACTIVE	0x08
268 #define ACPI_TRIPS_DEVICES	0x10
269 
270 #define ACPI_TRIPS_REFRESH_THRESHOLDS	(ACPI_TRIPS_PASSIVE | ACPI_TRIPS_ACTIVE)
271 #define ACPI_TRIPS_REFRESH_DEVICES	ACPI_TRIPS_DEVICES
272 
273 #define ACPI_TRIPS_INIT      (ACPI_TRIPS_CRITICAL | ACPI_TRIPS_HOT |	\
274 			      ACPI_TRIPS_PASSIVE | ACPI_TRIPS_ACTIVE |	\
275 			      ACPI_TRIPS_DEVICES)
276 
277 /*
278  * This exception is thrown out in two cases:
279  * 1.An invalid trip point becomes invalid or a valid trip point becomes invalid
280  *   when re-evaluating the AML code.
281  * 2.TODO: Devices listed in _PSL, _ALx, _TZD may change.
282  *   We need to re-bind the cooling devices of a thermal zone when this occurs.
283  */
284 #define ACPI_THERMAL_TRIPS_EXCEPTION(flags, str)	\
285 do {	\
286 	if (flags != ACPI_TRIPS_INIT)	\
287 		ACPI_EXCEPTION((AE_INFO, AE_ERROR,	\
288 		"ACPI thermal trip point %s changed\n"	\
289 		"Please send acpidump to linux-acpi@vger.kernel.org\n", str)); \
290 } while (0)
291 
292 static int acpi_thermal_trips_update(struct acpi_thermal *tz, int flag)
293 {
294 	acpi_status status = AE_OK;
295 	unsigned long long tmp;
296 	struct acpi_handle_list devices;
297 	int valid = 0;
298 	int i;
299 
300 	/* Critical Shutdown */
301 	if (flag & ACPI_TRIPS_CRITICAL) {
302 		status = acpi_evaluate_integer(tz->device->handle,
303 				"_CRT", NULL, &tmp);
304 		tz->trips.critical.temperature = tmp;
305 		/*
306 		 * Treat freezing temperatures as invalid as well; some
307 		 * BIOSes return really low values and cause reboots at startup.
308 		 * Below zero (Celsius) values clearly aren't right for sure..
309 		 * ... so lets discard those as invalid.
310 		 */
311 		if (ACPI_FAILURE(status)) {
312 			tz->trips.critical.flags.valid = 0;
313 			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
314 					  "No critical threshold\n"));
315 		} else if (tmp <= 2732) {
316 			printk(KERN_WARNING FW_BUG "Invalid critical threshold "
317 			       "(%llu)\n", tmp);
318 			tz->trips.critical.flags.valid = 0;
319 		} else {
320 			tz->trips.critical.flags.valid = 1;
321 			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
322 					  "Found critical threshold [%lu]\n",
323 					  tz->trips.critical.temperature));
324 		}
325 		if (tz->trips.critical.flags.valid == 1) {
326 			if (crt == -1) {
327 				tz->trips.critical.flags.valid = 0;
328 			} else if (crt > 0) {
329 				unsigned long crt_k = CELSIUS_TO_KELVIN(crt);
330 				/*
331 				 * Allow override critical threshold
332 				 */
333 				if (crt_k > tz->trips.critical.temperature)
334 					printk(KERN_WARNING PREFIX
335 						"Critical threshold %d C\n", crt);
336 				tz->trips.critical.temperature = crt_k;
337 			}
338 		}
339 	}
340 
341 	/* Critical Sleep (optional) */
342 	if (flag & ACPI_TRIPS_HOT) {
343 		status = acpi_evaluate_integer(tz->device->handle,
344 				"_HOT", NULL, &tmp);
345 		if (ACPI_FAILURE(status)) {
346 			tz->trips.hot.flags.valid = 0;
347 			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
348 					"No hot threshold\n"));
349 		} else {
350 			tz->trips.hot.temperature = tmp;
351 			tz->trips.hot.flags.valid = 1;
352 			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
353 					"Found hot threshold [%lu]\n",
354 					tz->trips.critical.temperature));
355 		}
356 	}
357 
358 	/* Passive (optional) */
359 	if (((flag & ACPI_TRIPS_PASSIVE) && tz->trips.passive.flags.valid) ||
360 		(flag == ACPI_TRIPS_INIT)) {
361 		valid = tz->trips.passive.flags.valid;
362 		if (psv == -1) {
363 			status = AE_SUPPORT;
364 		} else if (psv > 0) {
365 			tmp = CELSIUS_TO_KELVIN(psv);
366 			status = AE_OK;
367 		} else {
368 			status = acpi_evaluate_integer(tz->device->handle,
369 				"_PSV", NULL, &tmp);
370 		}
371 
372 		if (ACPI_FAILURE(status))
373 			tz->trips.passive.flags.valid = 0;
374 		else {
375 			tz->trips.passive.temperature = tmp;
376 			tz->trips.passive.flags.valid = 1;
377 			if (flag == ACPI_TRIPS_INIT) {
378 				status = acpi_evaluate_integer(
379 						tz->device->handle, "_TC1",
380 						NULL, &tmp);
381 				if (ACPI_FAILURE(status))
382 					tz->trips.passive.flags.valid = 0;
383 				else
384 					tz->trips.passive.tc1 = tmp;
385 				status = acpi_evaluate_integer(
386 						tz->device->handle, "_TC2",
387 						NULL, &tmp);
388 				if (ACPI_FAILURE(status))
389 					tz->trips.passive.flags.valid = 0;
390 				else
391 					tz->trips.passive.tc2 = tmp;
392 				status = acpi_evaluate_integer(
393 						tz->device->handle, "_TSP",
394 						NULL, &tmp);
395 				if (ACPI_FAILURE(status))
396 					tz->trips.passive.flags.valid = 0;
397 				else
398 					tz->trips.passive.tsp = tmp;
399 			}
400 		}
401 	}
402 	if ((flag & ACPI_TRIPS_DEVICES) && tz->trips.passive.flags.valid) {
403 		memset(&devices, 0, sizeof(struct acpi_handle_list));
404 		status = acpi_evaluate_reference(tz->device->handle, "_PSL",
405 							NULL, &devices);
406 		if (ACPI_FAILURE(status)) {
407 			printk(KERN_WARNING PREFIX
408 				"Invalid passive threshold\n");
409 			tz->trips.passive.flags.valid = 0;
410 		}
411 		else
412 			tz->trips.passive.flags.valid = 1;
413 
414 		if (memcmp(&tz->trips.passive.devices, &devices,
415 				sizeof(struct acpi_handle_list))) {
416 			memcpy(&tz->trips.passive.devices, &devices,
417 				sizeof(struct acpi_handle_list));
418 			ACPI_THERMAL_TRIPS_EXCEPTION(flag, "device");
419 		}
420 	}
421 	if ((flag & ACPI_TRIPS_PASSIVE) || (flag & ACPI_TRIPS_DEVICES)) {
422 		if (valid != tz->trips.passive.flags.valid)
423 				ACPI_THERMAL_TRIPS_EXCEPTION(flag, "state");
424 	}
425 
426 	/* Active (optional) */
427 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
428 		char name[5] = { '_', 'A', 'C', ('0' + i), '\0' };
429 		valid = tz->trips.active[i].flags.valid;
430 
431 		if (act == -1)
432 			break; /* disable all active trip points */
433 
434 		if ((flag == ACPI_TRIPS_INIT) || ((flag & ACPI_TRIPS_ACTIVE) &&
435 			tz->trips.active[i].flags.valid)) {
436 			status = acpi_evaluate_integer(tz->device->handle,
437 							name, NULL, &tmp);
438 			if (ACPI_FAILURE(status)) {
439 				tz->trips.active[i].flags.valid = 0;
440 				if (i == 0)
441 					break;
442 				if (act <= 0)
443 					break;
444 				if (i == 1)
445 					tz->trips.active[0].temperature =
446 						CELSIUS_TO_KELVIN(act);
447 				else
448 					/*
449 					 * Don't allow override higher than
450 					 * the next higher trip point
451 					 */
452 					tz->trips.active[i - 1].temperature =
453 						(tz->trips.active[i - 2].temperature <
454 						CELSIUS_TO_KELVIN(act) ?
455 						tz->trips.active[i - 2].temperature :
456 						CELSIUS_TO_KELVIN(act));
457 				break;
458 			} else {
459 				tz->trips.active[i].temperature = tmp;
460 				tz->trips.active[i].flags.valid = 1;
461 			}
462 		}
463 
464 		name[2] = 'L';
465 		if ((flag & ACPI_TRIPS_DEVICES) && tz->trips.active[i].flags.valid ) {
466 			memset(&devices, 0, sizeof(struct acpi_handle_list));
467 			status = acpi_evaluate_reference(tz->device->handle,
468 						name, NULL, &devices);
469 			if (ACPI_FAILURE(status)) {
470 				printk(KERN_WARNING PREFIX
471 					"Invalid active%d threshold\n", i);
472 				tz->trips.active[i].flags.valid = 0;
473 			}
474 			else
475 				tz->trips.active[i].flags.valid = 1;
476 
477 			if (memcmp(&tz->trips.active[i].devices, &devices,
478 					sizeof(struct acpi_handle_list))) {
479 				memcpy(&tz->trips.active[i].devices, &devices,
480 					sizeof(struct acpi_handle_list));
481 				ACPI_THERMAL_TRIPS_EXCEPTION(flag, "device");
482 			}
483 		}
484 		if ((flag & ACPI_TRIPS_ACTIVE) || (flag & ACPI_TRIPS_DEVICES))
485 			if (valid != tz->trips.active[i].flags.valid)
486 				ACPI_THERMAL_TRIPS_EXCEPTION(flag, "state");
487 
488 		if (!tz->trips.active[i].flags.valid)
489 			break;
490 	}
491 
492 	if (flag & ACPI_TRIPS_DEVICES) {
493 		memset(&devices, 0, sizeof(struct acpi_handle_list));
494 		status = acpi_evaluate_reference(tz->device->handle, "_TZD",
495 						NULL, &devices);
496 		if (memcmp(&tz->devices, &devices,
497 				sizeof(struct acpi_handle_list))) {
498 			memcpy(&tz->devices, &devices,
499 				sizeof(struct acpi_handle_list));
500 			ACPI_THERMAL_TRIPS_EXCEPTION(flag, "device");
501 		}
502 	}
503 
504 	return 0;
505 }
506 
507 static int acpi_thermal_get_trip_points(struct acpi_thermal *tz)
508 {
509 	int i, valid, ret = acpi_thermal_trips_update(tz, ACPI_TRIPS_INIT);
510 
511 	if (ret)
512 		return ret;
513 
514 	valid = tz->trips.critical.flags.valid |
515 		tz->trips.hot.flags.valid |
516 		tz->trips.passive.flags.valid;
517 
518 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++)
519 		valid |= tz->trips.active[i].flags.valid;
520 
521 	if (!valid) {
522 		printk(KERN_WARNING FW_BUG "No valid trip found\n");
523 		return -ENODEV;
524 	}
525 	return 0;
526 }
527 
528 static void acpi_thermal_check(void *data)
529 {
530 	struct acpi_thermal *tz = data;
531 
532 	thermal_zone_device_update(tz->thermal_zone);
533 }
534 
535 /* sys I/F for generic thermal sysfs support */
536 #define KELVIN_TO_MILLICELSIUS(t, off) (((t) - (off)) * 100)
537 
538 static int thermal_get_temp(struct thermal_zone_device *thermal,
539 			    unsigned long *temp)
540 {
541 	struct acpi_thermal *tz = thermal->devdata;
542 	int result;
543 
544 	if (!tz)
545 		return -EINVAL;
546 
547 	result = acpi_thermal_get_temperature(tz);
548 	if (result)
549 		return result;
550 
551 	*temp = KELVIN_TO_MILLICELSIUS(tz->temperature, tz->kelvin_offset);
552 	return 0;
553 }
554 
555 static const char enabled[] = "kernel";
556 static const char disabled[] = "user";
557 static int thermal_get_mode(struct thermal_zone_device *thermal,
558 				enum thermal_device_mode *mode)
559 {
560 	struct acpi_thermal *tz = thermal->devdata;
561 
562 	if (!tz)
563 		return -EINVAL;
564 
565 	*mode = tz->tz_enabled ? THERMAL_DEVICE_ENABLED :
566 		THERMAL_DEVICE_DISABLED;
567 
568 	return 0;
569 }
570 
571 static int thermal_set_mode(struct thermal_zone_device *thermal,
572 				enum thermal_device_mode mode)
573 {
574 	struct acpi_thermal *tz = thermal->devdata;
575 	int enable;
576 
577 	if (!tz)
578 		return -EINVAL;
579 
580 	/*
581 	 * enable/disable thermal management from ACPI thermal driver
582 	 */
583 	if (mode == THERMAL_DEVICE_ENABLED)
584 		enable = 1;
585 	else if (mode == THERMAL_DEVICE_DISABLED)
586 		enable = 0;
587 	else
588 		return -EINVAL;
589 
590 	if (enable != tz->tz_enabled) {
591 		tz->tz_enabled = enable;
592 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
593 			"%s ACPI thermal control\n",
594 			tz->tz_enabled ? enabled : disabled));
595 		acpi_thermal_check(tz);
596 	}
597 	return 0;
598 }
599 
600 static int thermal_get_trip_type(struct thermal_zone_device *thermal,
601 				 int trip, enum thermal_trip_type *type)
602 {
603 	struct acpi_thermal *tz = thermal->devdata;
604 	int i;
605 
606 	if (!tz || trip < 0)
607 		return -EINVAL;
608 
609 	if (tz->trips.critical.flags.valid) {
610 		if (!trip) {
611 			*type = THERMAL_TRIP_CRITICAL;
612 			return 0;
613 		}
614 		trip--;
615 	}
616 
617 	if (tz->trips.hot.flags.valid) {
618 		if (!trip) {
619 			*type = THERMAL_TRIP_HOT;
620 			return 0;
621 		}
622 		trip--;
623 	}
624 
625 	if (tz->trips.passive.flags.valid) {
626 		if (!trip) {
627 			*type = THERMAL_TRIP_PASSIVE;
628 			return 0;
629 		}
630 		trip--;
631 	}
632 
633 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE &&
634 		tz->trips.active[i].flags.valid; i++) {
635 		if (!trip) {
636 			*type = THERMAL_TRIP_ACTIVE;
637 			return 0;
638 		}
639 		trip--;
640 	}
641 
642 	return -EINVAL;
643 }
644 
645 static int thermal_get_trip_temp(struct thermal_zone_device *thermal,
646 				 int trip, unsigned long *temp)
647 {
648 	struct acpi_thermal *tz = thermal->devdata;
649 	int i;
650 
651 	if (!tz || trip < 0)
652 		return -EINVAL;
653 
654 	if (tz->trips.critical.flags.valid) {
655 		if (!trip) {
656 			*temp = KELVIN_TO_MILLICELSIUS(
657 				tz->trips.critical.temperature,
658 				tz->kelvin_offset);
659 			return 0;
660 		}
661 		trip--;
662 	}
663 
664 	if (tz->trips.hot.flags.valid) {
665 		if (!trip) {
666 			*temp = KELVIN_TO_MILLICELSIUS(
667 				tz->trips.hot.temperature,
668 				tz->kelvin_offset);
669 			return 0;
670 		}
671 		trip--;
672 	}
673 
674 	if (tz->trips.passive.flags.valid) {
675 		if (!trip) {
676 			*temp = KELVIN_TO_MILLICELSIUS(
677 				tz->trips.passive.temperature,
678 				tz->kelvin_offset);
679 			return 0;
680 		}
681 		trip--;
682 	}
683 
684 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE &&
685 		tz->trips.active[i].flags.valid; i++) {
686 		if (!trip) {
687 			*temp = KELVIN_TO_MILLICELSIUS(
688 				tz->trips.active[i].temperature,
689 				tz->kelvin_offset);
690 			return 0;
691 		}
692 		trip--;
693 	}
694 
695 	return -EINVAL;
696 }
697 
698 static int thermal_get_crit_temp(struct thermal_zone_device *thermal,
699 				unsigned long *temperature) {
700 	struct acpi_thermal *tz = thermal->devdata;
701 
702 	if (tz->trips.critical.flags.valid) {
703 		*temperature = KELVIN_TO_MILLICELSIUS(
704 				tz->trips.critical.temperature,
705 				tz->kelvin_offset);
706 		return 0;
707 	} else
708 		return -EINVAL;
709 }
710 
711 static int thermal_notify(struct thermal_zone_device *thermal, int trip,
712 			   enum thermal_trip_type trip_type)
713 {
714 	u8 type = 0;
715 	struct acpi_thermal *tz = thermal->devdata;
716 
717 	if (trip_type == THERMAL_TRIP_CRITICAL)
718 		type = ACPI_THERMAL_NOTIFY_CRITICAL;
719 	else if (trip_type == THERMAL_TRIP_HOT)
720 		type = ACPI_THERMAL_NOTIFY_HOT;
721 	else
722 		return 0;
723 
724 	acpi_bus_generate_proc_event(tz->device, type, 1);
725 	acpi_bus_generate_netlink_event(tz->device->pnp.device_class,
726 					dev_name(&tz->device->dev), type, 1);
727 
728 	if (trip_type == THERMAL_TRIP_CRITICAL && nocrt)
729 		return 1;
730 
731 	return 0;
732 }
733 
734 typedef int (*cb)(struct thermal_zone_device *, int,
735 		  struct thermal_cooling_device *);
736 static int acpi_thermal_cooling_device_cb(struct thermal_zone_device *thermal,
737 					struct thermal_cooling_device *cdev,
738 					cb action)
739 {
740 	struct acpi_device *device = cdev->devdata;
741 	struct acpi_thermal *tz = thermal->devdata;
742 	struct acpi_device *dev;
743 	acpi_status status;
744 	acpi_handle handle;
745 	int i;
746 	int j;
747 	int trip = -1;
748 	int result = 0;
749 
750 	if (tz->trips.critical.flags.valid)
751 		trip++;
752 
753 	if (tz->trips.hot.flags.valid)
754 		trip++;
755 
756 	if (tz->trips.passive.flags.valid) {
757 		trip++;
758 		for (i = 0; i < tz->trips.passive.devices.count;
759 		    i++) {
760 			handle = tz->trips.passive.devices.handles[i];
761 			status = acpi_bus_get_device(handle, &dev);
762 			if (ACPI_SUCCESS(status) && (dev == device)) {
763 				result = action(thermal, trip, cdev);
764 				if (result)
765 					goto failed;
766 			}
767 		}
768 	}
769 
770 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
771 		if (!tz->trips.active[i].flags.valid)
772 			break;
773 		trip++;
774 		for (j = 0;
775 		    j < tz->trips.active[i].devices.count;
776 		    j++) {
777 			handle = tz->trips.active[i].devices.handles[j];
778 			status = acpi_bus_get_device(handle, &dev);
779 			if (ACPI_SUCCESS(status) && (dev == device)) {
780 				result = action(thermal, trip, cdev);
781 				if (result)
782 					goto failed;
783 			}
784 		}
785 	}
786 
787 	for (i = 0; i < tz->devices.count; i++) {
788 		handle = tz->devices.handles[i];
789 		status = acpi_bus_get_device(handle, &dev);
790 		if (ACPI_SUCCESS(status) && (dev == device)) {
791 			result = action(thermal, -1, cdev);
792 			if (result)
793 				goto failed;
794 		}
795 	}
796 
797 failed:
798 	return result;
799 }
800 
801 static int
802 acpi_thermal_bind_cooling_device(struct thermal_zone_device *thermal,
803 					struct thermal_cooling_device *cdev)
804 {
805 	return acpi_thermal_cooling_device_cb(thermal, cdev,
806 				thermal_zone_bind_cooling_device);
807 }
808 
809 static int
810 acpi_thermal_unbind_cooling_device(struct thermal_zone_device *thermal,
811 					struct thermal_cooling_device *cdev)
812 {
813 	return acpi_thermal_cooling_device_cb(thermal, cdev,
814 				thermal_zone_unbind_cooling_device);
815 }
816 
817 static const struct thermal_zone_device_ops acpi_thermal_zone_ops = {
818 	.bind = acpi_thermal_bind_cooling_device,
819 	.unbind	= acpi_thermal_unbind_cooling_device,
820 	.get_temp = thermal_get_temp,
821 	.get_mode = thermal_get_mode,
822 	.set_mode = thermal_set_mode,
823 	.get_trip_type = thermal_get_trip_type,
824 	.get_trip_temp = thermal_get_trip_temp,
825 	.get_crit_temp = thermal_get_crit_temp,
826 	.notify = thermal_notify,
827 };
828 
829 static int acpi_thermal_register_thermal_zone(struct acpi_thermal *tz)
830 {
831 	int trips = 0;
832 	int result;
833 	acpi_status status;
834 	int i;
835 
836 	if (tz->trips.critical.flags.valid)
837 		trips++;
838 
839 	if (tz->trips.hot.flags.valid)
840 		trips++;
841 
842 	if (tz->trips.passive.flags.valid)
843 		trips++;
844 
845 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE &&
846 			tz->trips.active[i].flags.valid; i++, trips++);
847 
848 	if (tz->trips.passive.flags.valid)
849 		tz->thermal_zone =
850 			thermal_zone_device_register("acpitz", trips, tz,
851 						     &acpi_thermal_zone_ops,
852 						     tz->trips.passive.tc1,
853 						     tz->trips.passive.tc2,
854 						     tz->trips.passive.tsp*100,
855 						     tz->polling_frequency*100);
856 	else
857 		tz->thermal_zone =
858 			thermal_zone_device_register("acpitz", trips, tz,
859 						     &acpi_thermal_zone_ops,
860 						     0, 0, 0,
861 						     tz->polling_frequency*100);
862 	if (IS_ERR(tz->thermal_zone))
863 		return -ENODEV;
864 
865 	result = sysfs_create_link(&tz->device->dev.kobj,
866 				   &tz->thermal_zone->device.kobj, "thermal_zone");
867 	if (result)
868 		return result;
869 
870 	result = sysfs_create_link(&tz->thermal_zone->device.kobj,
871 				   &tz->device->dev.kobj, "device");
872 	if (result)
873 		return result;
874 
875 	status = acpi_attach_data(tz->device->handle,
876 				  acpi_bus_private_data_handler,
877 				  tz->thermal_zone);
878 	if (ACPI_FAILURE(status)) {
879 		printk(KERN_ERR PREFIX
880 				"Error attaching device data\n");
881 		return -ENODEV;
882 	}
883 
884 	tz->tz_enabled = 1;
885 
886 	dev_info(&tz->device->dev, "registered as thermal_zone%d\n",
887 		 tz->thermal_zone->id);
888 	return 0;
889 }
890 
891 static void acpi_thermal_unregister_thermal_zone(struct acpi_thermal *tz)
892 {
893 	sysfs_remove_link(&tz->device->dev.kobj, "thermal_zone");
894 	sysfs_remove_link(&tz->thermal_zone->device.kobj, "device");
895 	thermal_zone_device_unregister(tz->thermal_zone);
896 	tz->thermal_zone = NULL;
897 	acpi_detach_data(tz->device->handle, acpi_bus_private_data_handler);
898 }
899 
900 
901 /* --------------------------------------------------------------------------
902                                  Driver Interface
903    -------------------------------------------------------------------------- */
904 
905 static void acpi_thermal_notify(struct acpi_device *device, u32 event)
906 {
907 	struct acpi_thermal *tz = acpi_driver_data(device);
908 
909 
910 	if (!tz)
911 		return;
912 
913 	switch (event) {
914 	case ACPI_THERMAL_NOTIFY_TEMPERATURE:
915 		acpi_thermal_check(tz);
916 		break;
917 	case ACPI_THERMAL_NOTIFY_THRESHOLDS:
918 		acpi_thermal_trips_update(tz, ACPI_TRIPS_REFRESH_THRESHOLDS);
919 		acpi_thermal_check(tz);
920 		acpi_bus_generate_proc_event(device, event, 0);
921 		acpi_bus_generate_netlink_event(device->pnp.device_class,
922 						  dev_name(&device->dev), event, 0);
923 		break;
924 	case ACPI_THERMAL_NOTIFY_DEVICES:
925 		acpi_thermal_trips_update(tz, ACPI_TRIPS_REFRESH_DEVICES);
926 		acpi_thermal_check(tz);
927 		acpi_bus_generate_proc_event(device, event, 0);
928 		acpi_bus_generate_netlink_event(device->pnp.device_class,
929 						  dev_name(&device->dev), event, 0);
930 		break;
931 	default:
932 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
933 				  "Unsupported event [0x%x]\n", event));
934 		break;
935 	}
936 }
937 
938 static int acpi_thermal_get_info(struct acpi_thermal *tz)
939 {
940 	int result = 0;
941 
942 
943 	if (!tz)
944 		return -EINVAL;
945 
946 	/* Get trip points [_CRT, _PSV, etc.] (required) */
947 	result = acpi_thermal_get_trip_points(tz);
948 	if (result)
949 		return result;
950 
951 	/* Get temperature [_TMP] (required) */
952 	result = acpi_thermal_get_temperature(tz);
953 	if (result)
954 		return result;
955 
956 	/* Set the cooling mode [_SCP] to active cooling (default) */
957 	result = acpi_thermal_set_cooling_mode(tz, ACPI_THERMAL_MODE_ACTIVE);
958 	if (!result)
959 		tz->flags.cooling_mode = 1;
960 
961 	/* Get default polling frequency [_TZP] (optional) */
962 	if (tzp)
963 		tz->polling_frequency = tzp;
964 	else
965 		acpi_thermal_get_polling_frequency(tz);
966 
967 	return 0;
968 }
969 
970 /*
971  * The exact offset between Kelvin and degree Celsius is 273.15. However ACPI
972  * handles temperature values with a single decimal place. As a consequence,
973  * some implementations use an offset of 273.1 and others use an offset of
974  * 273.2. Try to find out which one is being used, to present the most
975  * accurate and visually appealing number.
976  *
977  * The heuristic below should work for all ACPI thermal zones which have a
978  * critical trip point with a value being a multiple of 0.5 degree Celsius.
979  */
980 static void acpi_thermal_guess_offset(struct acpi_thermal *tz)
981 {
982 	if (tz->trips.critical.flags.valid &&
983 	    (tz->trips.critical.temperature % 5) == 1)
984 		tz->kelvin_offset = 2731;
985 	else
986 		tz->kelvin_offset = 2732;
987 }
988 
989 static int acpi_thermal_add(struct acpi_device *device)
990 {
991 	int result = 0;
992 	struct acpi_thermal *tz = NULL;
993 
994 
995 	if (!device)
996 		return -EINVAL;
997 
998 	tz = kzalloc(sizeof(struct acpi_thermal), GFP_KERNEL);
999 	if (!tz)
1000 		return -ENOMEM;
1001 
1002 	tz->device = device;
1003 	strcpy(tz->name, device->pnp.bus_id);
1004 	strcpy(acpi_device_name(device), ACPI_THERMAL_DEVICE_NAME);
1005 	strcpy(acpi_device_class(device), ACPI_THERMAL_CLASS);
1006 	device->driver_data = tz;
1007 	mutex_init(&tz->lock);
1008 
1009 
1010 	result = acpi_thermal_get_info(tz);
1011 	if (result)
1012 		goto free_memory;
1013 
1014 	acpi_thermal_guess_offset(tz);
1015 
1016 	result = acpi_thermal_register_thermal_zone(tz);
1017 	if (result)
1018 		goto free_memory;
1019 
1020 	printk(KERN_INFO PREFIX "%s [%s] (%ld C)\n",
1021 	       acpi_device_name(device), acpi_device_bid(device),
1022 	       KELVIN_TO_CELSIUS(tz->temperature));
1023 	goto end;
1024 
1025 free_memory:
1026 	kfree(tz);
1027 end:
1028 	return result;
1029 }
1030 
1031 static int acpi_thermal_remove(struct acpi_device *device, int type)
1032 {
1033 	struct acpi_thermal *tz = NULL;
1034 
1035 	if (!device || !acpi_driver_data(device))
1036 		return -EINVAL;
1037 
1038 	tz = acpi_driver_data(device);
1039 
1040 	acpi_thermal_unregister_thermal_zone(tz);
1041 	mutex_destroy(&tz->lock);
1042 	kfree(tz);
1043 	return 0;
1044 }
1045 
1046 static int acpi_thermal_resume(struct device *dev)
1047 {
1048 	struct acpi_thermal *tz;
1049 	int i, j, power_state, result;
1050 
1051 	if (!dev)
1052 		return -EINVAL;
1053 
1054 	tz = acpi_driver_data(to_acpi_device(dev));
1055 	if (!tz)
1056 		return -EINVAL;
1057 
1058 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
1059 		if (!(&tz->trips.active[i]))
1060 			break;
1061 		if (!tz->trips.active[i].flags.valid)
1062 			break;
1063 		tz->trips.active[i].flags.enabled = 1;
1064 		for (j = 0; j < tz->trips.active[i].devices.count; j++) {
1065 			result = acpi_bus_update_power(
1066 					tz->trips.active[i].devices.handles[j],
1067 					&power_state);
1068 			if (result || (power_state != ACPI_STATE_D0)) {
1069 				tz->trips.active[i].flags.enabled = 0;
1070 				break;
1071 			}
1072 		}
1073 		tz->state.active |= tz->trips.active[i].flags.enabled;
1074 	}
1075 
1076 	acpi_thermal_check(tz);
1077 
1078 	return AE_OK;
1079 }
1080 
1081 static int thermal_act(const struct dmi_system_id *d) {
1082 
1083 	if (act == 0) {
1084 		printk(KERN_NOTICE "ACPI: %s detected: "
1085 			"disabling all active thermal trip points\n", d->ident);
1086 		act = -1;
1087 	}
1088 	return 0;
1089 }
1090 static int thermal_nocrt(const struct dmi_system_id *d) {
1091 
1092 	printk(KERN_NOTICE "ACPI: %s detected: "
1093 		"disabling all critical thermal trip point actions.\n", d->ident);
1094 	nocrt = 1;
1095 	return 0;
1096 }
1097 static int thermal_tzp(const struct dmi_system_id *d) {
1098 
1099 	if (tzp == 0) {
1100 		printk(KERN_NOTICE "ACPI: %s detected: "
1101 			"enabling thermal zone polling\n", d->ident);
1102 		tzp = 300;	/* 300 dS = 30 Seconds */
1103 	}
1104 	return 0;
1105 }
1106 static int thermal_psv(const struct dmi_system_id *d) {
1107 
1108 	if (psv == 0) {
1109 		printk(KERN_NOTICE "ACPI: %s detected: "
1110 			"disabling all passive thermal trip points\n", d->ident);
1111 		psv = -1;
1112 	}
1113 	return 0;
1114 }
1115 
1116 static struct dmi_system_id thermal_dmi_table[] __initdata = {
1117 	/*
1118 	 * Award BIOS on this AOpen makes thermal control almost worthless.
1119 	 * http://bugzilla.kernel.org/show_bug.cgi?id=8842
1120 	 */
1121 	{
1122 	 .callback = thermal_act,
1123 	 .ident = "AOpen i915GMm-HFS",
1124 	 .matches = {
1125 		DMI_MATCH(DMI_BOARD_VENDOR, "AOpen"),
1126 		DMI_MATCH(DMI_BOARD_NAME, "i915GMm-HFS"),
1127 		},
1128 	},
1129 	{
1130 	 .callback = thermal_psv,
1131 	 .ident = "AOpen i915GMm-HFS",
1132 	 .matches = {
1133 		DMI_MATCH(DMI_BOARD_VENDOR, "AOpen"),
1134 		DMI_MATCH(DMI_BOARD_NAME, "i915GMm-HFS"),
1135 		},
1136 	},
1137 	{
1138 	 .callback = thermal_tzp,
1139 	 .ident = "AOpen i915GMm-HFS",
1140 	 .matches = {
1141 		DMI_MATCH(DMI_BOARD_VENDOR, "AOpen"),
1142 		DMI_MATCH(DMI_BOARD_NAME, "i915GMm-HFS"),
1143 		},
1144 	},
1145 	{
1146 	 .callback = thermal_nocrt,
1147 	 .ident = "Gigabyte GA-7ZX",
1148 	 .matches = {
1149 		DMI_MATCH(DMI_BOARD_VENDOR, "Gigabyte Technology Co., Ltd."),
1150 		DMI_MATCH(DMI_BOARD_NAME, "7ZX"),
1151 		},
1152 	},
1153 	{}
1154 };
1155 
1156 static int __init acpi_thermal_init(void)
1157 {
1158 	int result = 0;
1159 
1160 	dmi_check_system(thermal_dmi_table);
1161 
1162 	if (off) {
1163 		printk(KERN_NOTICE "ACPI: thermal control disabled\n");
1164 		return -ENODEV;
1165 	}
1166 
1167 	result = acpi_bus_register_driver(&acpi_thermal_driver);
1168 	if (result < 0)
1169 		return -ENODEV;
1170 
1171 	return 0;
1172 }
1173 
1174 static void __exit acpi_thermal_exit(void)
1175 {
1176 
1177 	acpi_bus_unregister_driver(&acpi_thermal_driver);
1178 
1179 	return;
1180 }
1181 
1182 module_init(acpi_thermal_init);
1183 module_exit(acpi_thermal_exit);
1184