xref: /linux/drivers/acpi/thermal.c (revision fd639726bf15fca8ee1a00dce8e0096d0ad9bd18)
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  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
20  *
21  *  This driver fully implements the ACPI thermal policy as described in the
22  *  ACPI 2.0 Specification.
23  *
24  *  TBD: 1. Implement passive cooling hysteresis.
25  *       2. Enhance passive cooling (CPU) states/limit interface to support
26  *          concepts of 'multiple limiters', upper/lower limits, etc.
27  *
28  */
29 
30 #include <linux/kernel.h>
31 #include <linux/module.h>
32 #include <linux/dmi.h>
33 #include <linux/init.h>
34 #include <linux/slab.h>
35 #include <linux/types.h>
36 #include <linux/jiffies.h>
37 #include <linux/kmod.h>
38 #include <linux/reboot.h>
39 #include <linux/device.h>
40 #include <linux/thermal.h>
41 #include <linux/acpi.h>
42 #include <linux/workqueue.h>
43 #include <linux/uaccess.h>
44 
45 #define PREFIX "ACPI: "
46 
47 #define ACPI_THERMAL_CLASS		"thermal_zone"
48 #define ACPI_THERMAL_DEVICE_NAME	"Thermal Zone"
49 #define ACPI_THERMAL_NOTIFY_TEMPERATURE	0x80
50 #define ACPI_THERMAL_NOTIFY_THRESHOLDS	0x81
51 #define ACPI_THERMAL_NOTIFY_DEVICES	0x82
52 #define ACPI_THERMAL_NOTIFY_CRITICAL	0xF0
53 #define ACPI_THERMAL_NOTIFY_HOT		0xF1
54 #define ACPI_THERMAL_MODE_ACTIVE	0x00
55 
56 #define ACPI_THERMAL_MAX_ACTIVE	10
57 #define ACPI_THERMAL_MAX_LIMIT_STR_LEN 65
58 
59 #define _COMPONENT		ACPI_THERMAL_COMPONENT
60 ACPI_MODULE_NAME("thermal");
61 
62 MODULE_AUTHOR("Paul Diefenbaugh");
63 MODULE_DESCRIPTION("ACPI Thermal Zone Driver");
64 MODULE_LICENSE("GPL");
65 
66 static int act;
67 module_param(act, int, 0644);
68 MODULE_PARM_DESC(act, "Disable or override all lowest active trip points.");
69 
70 static int crt;
71 module_param(crt, int, 0644);
72 MODULE_PARM_DESC(crt, "Disable or lower all critical trip points.");
73 
74 static int tzp;
75 module_param(tzp, int, 0444);
76 MODULE_PARM_DESC(tzp, "Thermal zone polling frequency, in 1/10 seconds.");
77 
78 static int nocrt;
79 module_param(nocrt, int, 0);
80 MODULE_PARM_DESC(nocrt, "Set to take no action upon ACPI thermal zone critical trips points.");
81 
82 static int off;
83 module_param(off, int, 0);
84 MODULE_PARM_DESC(off, "Set to disable ACPI thermal support.");
85 
86 static int psv;
87 module_param(psv, int, 0644);
88 MODULE_PARM_DESC(psv, "Disable or override all passive trip points.");
89 
90 static struct workqueue_struct *acpi_thermal_pm_queue;
91 
92 static int acpi_thermal_add(struct acpi_device *device);
93 static int acpi_thermal_remove(struct acpi_device *device);
94 static void acpi_thermal_notify(struct acpi_device *device, u32 event);
95 
96 static const struct acpi_device_id  thermal_device_ids[] = {
97 	{ACPI_THERMAL_HID, 0},
98 	{"", 0},
99 };
100 MODULE_DEVICE_TABLE(acpi, thermal_device_ids);
101 
102 #ifdef CONFIG_PM_SLEEP
103 static int acpi_thermal_suspend(struct device *dev);
104 static int acpi_thermal_resume(struct device *dev);
105 #else
106 #define acpi_thermal_suspend NULL
107 #define acpi_thermal_resume NULL
108 #endif
109 static SIMPLE_DEV_PM_OPS(acpi_thermal_pm, acpi_thermal_suspend, acpi_thermal_resume);
110 
111 static struct acpi_driver acpi_thermal_driver = {
112 	.name = "thermal",
113 	.class = ACPI_THERMAL_CLASS,
114 	.ids = thermal_device_ids,
115 	.ops = {
116 		.add = acpi_thermal_add,
117 		.remove = acpi_thermal_remove,
118 		.notify = acpi_thermal_notify,
119 		},
120 	.drv.pm = &acpi_thermal_pm,
121 };
122 
123 struct acpi_thermal_state {
124 	u8 critical:1;
125 	u8 hot:1;
126 	u8 passive:1;
127 	u8 active:1;
128 	u8 reserved:4;
129 	int active_index;
130 };
131 
132 struct acpi_thermal_state_flags {
133 	u8 valid:1;
134 	u8 enabled:1;
135 	u8 reserved:6;
136 };
137 
138 struct acpi_thermal_critical {
139 	struct acpi_thermal_state_flags flags;
140 	unsigned long temperature;
141 };
142 
143 struct acpi_thermal_hot {
144 	struct acpi_thermal_state_flags flags;
145 	unsigned long temperature;
146 };
147 
148 struct acpi_thermal_passive {
149 	struct acpi_thermal_state_flags flags;
150 	unsigned long temperature;
151 	unsigned long tc1;
152 	unsigned long tc2;
153 	unsigned long tsp;
154 	struct acpi_handle_list devices;
155 };
156 
157 struct acpi_thermal_active {
158 	struct acpi_thermal_state_flags flags;
159 	unsigned long temperature;
160 	struct acpi_handle_list devices;
161 };
162 
163 struct acpi_thermal_trips {
164 	struct acpi_thermal_critical critical;
165 	struct acpi_thermal_hot hot;
166 	struct acpi_thermal_passive passive;
167 	struct acpi_thermal_active active[ACPI_THERMAL_MAX_ACTIVE];
168 };
169 
170 struct acpi_thermal_flags {
171 	u8 cooling_mode:1;	/* _SCP */
172 	u8 devices:1;		/* _TZD */
173 	u8 reserved:6;
174 };
175 
176 struct acpi_thermal {
177 	struct acpi_device * device;
178 	acpi_bus_id name;
179 	unsigned long temperature;
180 	unsigned long last_temperature;
181 	unsigned long polling_frequency;
182 	volatile u8 zombie;
183 	struct acpi_thermal_flags flags;
184 	struct acpi_thermal_state state;
185 	struct acpi_thermal_trips trips;
186 	struct acpi_handle_list devices;
187 	struct thermal_zone_device *thermal_zone;
188 	int tz_enabled;
189 	int kelvin_offset;
190 	struct work_struct thermal_check_work;
191 };
192 
193 /* --------------------------------------------------------------------------
194                              Thermal Zone Management
195    -------------------------------------------------------------------------- */
196 
197 static int acpi_thermal_get_temperature(struct acpi_thermal *tz)
198 {
199 	acpi_status status = AE_OK;
200 	unsigned long long tmp;
201 
202 	if (!tz)
203 		return -EINVAL;
204 
205 	tz->last_temperature = tz->temperature;
206 
207 	status = acpi_evaluate_integer(tz->device->handle, "_TMP", NULL, &tmp);
208 	if (ACPI_FAILURE(status))
209 		return -ENODEV;
210 
211 	tz->temperature = tmp;
212 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Temperature is %lu dK\n",
213 			  tz->temperature));
214 
215 	return 0;
216 }
217 
218 static int acpi_thermal_get_polling_frequency(struct acpi_thermal *tz)
219 {
220 	acpi_status status = AE_OK;
221 	unsigned long long tmp;
222 
223 	if (!tz)
224 		return -EINVAL;
225 
226 	status = acpi_evaluate_integer(tz->device->handle, "_TZP", NULL, &tmp);
227 	if (ACPI_FAILURE(status))
228 		return -ENODEV;
229 
230 	tz->polling_frequency = tmp;
231 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Polling frequency is %lu dS\n",
232 			  tz->polling_frequency));
233 
234 	return 0;
235 }
236 
237 static int acpi_thermal_set_cooling_mode(struct acpi_thermal *tz, int mode)
238 {
239 	if (!tz)
240 		return -EINVAL;
241 
242 	if (!acpi_has_method(tz->device->handle, "_SCP")) {
243 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "_SCP not present\n"));
244 		return -ENODEV;
245 	} else if (ACPI_FAILURE(acpi_execute_simple_method(tz->device->handle,
246 							   "_SCP", mode))) {
247 		return -ENODEV;
248 	}
249 
250 	return 0;
251 }
252 
253 #define ACPI_TRIPS_CRITICAL	0x01
254 #define ACPI_TRIPS_HOT		0x02
255 #define ACPI_TRIPS_PASSIVE	0x04
256 #define ACPI_TRIPS_ACTIVE	0x08
257 #define ACPI_TRIPS_DEVICES	0x10
258 
259 #define ACPI_TRIPS_REFRESH_THRESHOLDS	(ACPI_TRIPS_PASSIVE | ACPI_TRIPS_ACTIVE)
260 #define ACPI_TRIPS_REFRESH_DEVICES	ACPI_TRIPS_DEVICES
261 
262 #define ACPI_TRIPS_INIT      (ACPI_TRIPS_CRITICAL | ACPI_TRIPS_HOT |	\
263 			      ACPI_TRIPS_PASSIVE | ACPI_TRIPS_ACTIVE |	\
264 			      ACPI_TRIPS_DEVICES)
265 
266 /*
267  * This exception is thrown out in two cases:
268  * 1.An invalid trip point becomes invalid or a valid trip point becomes invalid
269  *   when re-evaluating the AML code.
270  * 2.TODO: Devices listed in _PSL, _ALx, _TZD may change.
271  *   We need to re-bind the cooling devices of a thermal zone when this occurs.
272  */
273 #define ACPI_THERMAL_TRIPS_EXCEPTION(flags, str)	\
274 do {	\
275 	if (flags != ACPI_TRIPS_INIT)	\
276 		ACPI_EXCEPTION((AE_INFO, AE_ERROR,	\
277 		"ACPI thermal trip point %s changed\n"	\
278 		"Please send acpidump to linux-acpi@vger.kernel.org", str)); \
279 } while (0)
280 
281 static int acpi_thermal_trips_update(struct acpi_thermal *tz, int flag)
282 {
283 	acpi_status status = AE_OK;
284 	unsigned long long tmp;
285 	struct acpi_handle_list devices;
286 	int valid = 0;
287 	int i;
288 
289 	/* Critical Shutdown */
290 	if (flag & ACPI_TRIPS_CRITICAL) {
291 		status = acpi_evaluate_integer(tz->device->handle,
292 				"_CRT", NULL, &tmp);
293 		tz->trips.critical.temperature = tmp;
294 		/*
295 		 * Treat freezing temperatures as invalid as well; some
296 		 * BIOSes return really low values and cause reboots at startup.
297 		 * Below zero (Celsius) values clearly aren't right for sure..
298 		 * ... so lets discard those as invalid.
299 		 */
300 		if (ACPI_FAILURE(status)) {
301 			tz->trips.critical.flags.valid = 0;
302 			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
303 					  "No critical threshold\n"));
304 		} else if (tmp <= 2732) {
305 			pr_warn(FW_BUG "Invalid critical threshold (%llu)\n",
306 				tmp);
307 			tz->trips.critical.flags.valid = 0;
308 		} else {
309 			tz->trips.critical.flags.valid = 1;
310 			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
311 					  "Found critical threshold [%lu]\n",
312 					  tz->trips.critical.temperature));
313 		}
314 		if (tz->trips.critical.flags.valid == 1) {
315 			if (crt == -1) {
316 				tz->trips.critical.flags.valid = 0;
317 			} else if (crt > 0) {
318 				unsigned long crt_k = CELSIUS_TO_DECI_KELVIN(crt);
319 				/*
320 				 * Allow override critical threshold
321 				 */
322 				if (crt_k > tz->trips.critical.temperature)
323 					pr_warn(PREFIX "Critical threshold %d C\n",
324 						crt);
325 				tz->trips.critical.temperature = crt_k;
326 			}
327 		}
328 	}
329 
330 	/* Critical Sleep (optional) */
331 	if (flag & ACPI_TRIPS_HOT) {
332 		status = acpi_evaluate_integer(tz->device->handle,
333 				"_HOT", NULL, &tmp);
334 		if (ACPI_FAILURE(status)) {
335 			tz->trips.hot.flags.valid = 0;
336 			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
337 					"No hot threshold\n"));
338 		} else {
339 			tz->trips.hot.temperature = tmp;
340 			tz->trips.hot.flags.valid = 1;
341 			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
342 					"Found hot threshold [%lu]\n",
343 					tz->trips.hot.temperature));
344 		}
345 	}
346 
347 	/* Passive (optional) */
348 	if (((flag & ACPI_TRIPS_PASSIVE) && tz->trips.passive.flags.valid) ||
349 		(flag == ACPI_TRIPS_INIT)) {
350 		valid = tz->trips.passive.flags.valid;
351 		if (psv == -1) {
352 			status = AE_SUPPORT;
353 		} else if (psv > 0) {
354 			tmp = CELSIUS_TO_DECI_KELVIN(psv);
355 			status = AE_OK;
356 		} else {
357 			status = acpi_evaluate_integer(tz->device->handle,
358 				"_PSV", NULL, &tmp);
359 		}
360 
361 		if (ACPI_FAILURE(status))
362 			tz->trips.passive.flags.valid = 0;
363 		else {
364 			tz->trips.passive.temperature = tmp;
365 			tz->trips.passive.flags.valid = 1;
366 			if (flag == ACPI_TRIPS_INIT) {
367 				status = acpi_evaluate_integer(
368 						tz->device->handle, "_TC1",
369 						NULL, &tmp);
370 				if (ACPI_FAILURE(status))
371 					tz->trips.passive.flags.valid = 0;
372 				else
373 					tz->trips.passive.tc1 = tmp;
374 				status = acpi_evaluate_integer(
375 						tz->device->handle, "_TC2",
376 						NULL, &tmp);
377 				if (ACPI_FAILURE(status))
378 					tz->trips.passive.flags.valid = 0;
379 				else
380 					tz->trips.passive.tc2 = tmp;
381 				status = acpi_evaluate_integer(
382 						tz->device->handle, "_TSP",
383 						NULL, &tmp);
384 				if (ACPI_FAILURE(status))
385 					tz->trips.passive.flags.valid = 0;
386 				else
387 					tz->trips.passive.tsp = tmp;
388 			}
389 		}
390 	}
391 	if ((flag & ACPI_TRIPS_DEVICES) && tz->trips.passive.flags.valid) {
392 		memset(&devices, 0, sizeof(struct acpi_handle_list));
393 		status = acpi_evaluate_reference(tz->device->handle, "_PSL",
394 							NULL, &devices);
395 		if (ACPI_FAILURE(status)) {
396 			pr_warn(PREFIX "Invalid passive threshold\n");
397 			tz->trips.passive.flags.valid = 0;
398 		}
399 		else
400 			tz->trips.passive.flags.valid = 1;
401 
402 		if (memcmp(&tz->trips.passive.devices, &devices,
403 				sizeof(struct acpi_handle_list))) {
404 			memcpy(&tz->trips.passive.devices, &devices,
405 				sizeof(struct acpi_handle_list));
406 			ACPI_THERMAL_TRIPS_EXCEPTION(flag, "device");
407 		}
408 	}
409 	if ((flag & ACPI_TRIPS_PASSIVE) || (flag & ACPI_TRIPS_DEVICES)) {
410 		if (valid != tz->trips.passive.flags.valid)
411 				ACPI_THERMAL_TRIPS_EXCEPTION(flag, "state");
412 	}
413 
414 	/* Active (optional) */
415 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
416 		char name[5] = { '_', 'A', 'C', ('0' + i), '\0' };
417 		valid = tz->trips.active[i].flags.valid;
418 
419 		if (act == -1)
420 			break; /* disable all active trip points */
421 
422 		if ((flag == ACPI_TRIPS_INIT) || ((flag & ACPI_TRIPS_ACTIVE) &&
423 			tz->trips.active[i].flags.valid)) {
424 			status = acpi_evaluate_integer(tz->device->handle,
425 							name, NULL, &tmp);
426 			if (ACPI_FAILURE(status)) {
427 				tz->trips.active[i].flags.valid = 0;
428 				if (i == 0)
429 					break;
430 				if (act <= 0)
431 					break;
432 				if (i == 1)
433 					tz->trips.active[0].temperature =
434 						CELSIUS_TO_DECI_KELVIN(act);
435 				else
436 					/*
437 					 * Don't allow override higher than
438 					 * the next higher trip point
439 					 */
440 					tz->trips.active[i - 1].temperature =
441 						(tz->trips.active[i - 2].temperature <
442 						CELSIUS_TO_DECI_KELVIN(act) ?
443 						tz->trips.active[i - 2].temperature :
444 						CELSIUS_TO_DECI_KELVIN(act));
445 				break;
446 			} else {
447 				tz->trips.active[i].temperature = tmp;
448 				tz->trips.active[i].flags.valid = 1;
449 			}
450 		}
451 
452 		name[2] = 'L';
453 		if ((flag & ACPI_TRIPS_DEVICES) && tz->trips.active[i].flags.valid ) {
454 			memset(&devices, 0, sizeof(struct acpi_handle_list));
455 			status = acpi_evaluate_reference(tz->device->handle,
456 						name, NULL, &devices);
457 			if (ACPI_FAILURE(status)) {
458 				pr_warn(PREFIX "Invalid active%d threshold\n",
459 					i);
460 				tz->trips.active[i].flags.valid = 0;
461 			}
462 			else
463 				tz->trips.active[i].flags.valid = 1;
464 
465 			if (memcmp(&tz->trips.active[i].devices, &devices,
466 					sizeof(struct acpi_handle_list))) {
467 				memcpy(&tz->trips.active[i].devices, &devices,
468 					sizeof(struct acpi_handle_list));
469 				ACPI_THERMAL_TRIPS_EXCEPTION(flag, "device");
470 			}
471 		}
472 		if ((flag & ACPI_TRIPS_ACTIVE) || (flag & ACPI_TRIPS_DEVICES))
473 			if (valid != tz->trips.active[i].flags.valid)
474 				ACPI_THERMAL_TRIPS_EXCEPTION(flag, "state");
475 
476 		if (!tz->trips.active[i].flags.valid)
477 			break;
478 	}
479 
480 	if ((flag & ACPI_TRIPS_DEVICES)
481 	    && acpi_has_method(tz->device->handle, "_TZD")) {
482 		memset(&devices, 0, sizeof(devices));
483 		status = acpi_evaluate_reference(tz->device->handle, "_TZD",
484 						NULL, &devices);
485 		if (ACPI_SUCCESS(status)
486 		    && memcmp(&tz->devices, &devices, sizeof(devices))) {
487 			tz->devices = devices;
488 			ACPI_THERMAL_TRIPS_EXCEPTION(flag, "device");
489 		}
490 	}
491 
492 	return 0;
493 }
494 
495 static int acpi_thermal_get_trip_points(struct acpi_thermal *tz)
496 {
497 	int i, valid, ret = acpi_thermal_trips_update(tz, ACPI_TRIPS_INIT);
498 
499 	if (ret)
500 		return ret;
501 
502 	valid = tz->trips.critical.flags.valid |
503 		tz->trips.hot.flags.valid |
504 		tz->trips.passive.flags.valid;
505 
506 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++)
507 		valid |= tz->trips.active[i].flags.valid;
508 
509 	if (!valid) {
510 		pr_warn(FW_BUG "No valid trip found\n");
511 		return -ENODEV;
512 	}
513 	return 0;
514 }
515 
516 static void acpi_thermal_check(void *data)
517 {
518 	struct acpi_thermal *tz = data;
519 
520 	if (!tz->tz_enabled)
521 		return;
522 
523 	thermal_zone_device_update(tz->thermal_zone,
524 				   THERMAL_EVENT_UNSPECIFIED);
525 }
526 
527 /* sys I/F for generic thermal sysfs support */
528 
529 static int thermal_get_temp(struct thermal_zone_device *thermal, int *temp)
530 {
531 	struct acpi_thermal *tz = thermal->devdata;
532 	int result;
533 
534 	if (!tz)
535 		return -EINVAL;
536 
537 	result = acpi_thermal_get_temperature(tz);
538 	if (result)
539 		return result;
540 
541 	*temp = DECI_KELVIN_TO_MILLICELSIUS_WITH_OFFSET(tz->temperature,
542 							tz->kelvin_offset);
543 	return 0;
544 }
545 
546 static int thermal_get_mode(struct thermal_zone_device *thermal,
547 				enum thermal_device_mode *mode)
548 {
549 	struct acpi_thermal *tz = thermal->devdata;
550 
551 	if (!tz)
552 		return -EINVAL;
553 
554 	*mode = tz->tz_enabled ? THERMAL_DEVICE_ENABLED :
555 		THERMAL_DEVICE_DISABLED;
556 
557 	return 0;
558 }
559 
560 static int thermal_set_mode(struct thermal_zone_device *thermal,
561 				enum thermal_device_mode mode)
562 {
563 	struct acpi_thermal *tz = thermal->devdata;
564 	int enable;
565 
566 	if (!tz)
567 		return -EINVAL;
568 
569 	/*
570 	 * enable/disable thermal management from ACPI thermal driver
571 	 */
572 	if (mode == THERMAL_DEVICE_ENABLED)
573 		enable = 1;
574 	else if (mode == THERMAL_DEVICE_DISABLED) {
575 		enable = 0;
576 		pr_warn("thermal zone will be disabled\n");
577 	} else
578 		return -EINVAL;
579 
580 	if (enable != tz->tz_enabled) {
581 		tz->tz_enabled = enable;
582 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
583 			"%s kernel ACPI thermal control\n",
584 			tz->tz_enabled ? "Enable" : "Disable"));
585 		acpi_thermal_check(tz);
586 	}
587 	return 0;
588 }
589 
590 static int thermal_get_trip_type(struct thermal_zone_device *thermal,
591 				 int trip, enum thermal_trip_type *type)
592 {
593 	struct acpi_thermal *tz = thermal->devdata;
594 	int i;
595 
596 	if (!tz || trip < 0)
597 		return -EINVAL;
598 
599 	if (tz->trips.critical.flags.valid) {
600 		if (!trip) {
601 			*type = THERMAL_TRIP_CRITICAL;
602 			return 0;
603 		}
604 		trip--;
605 	}
606 
607 	if (tz->trips.hot.flags.valid) {
608 		if (!trip) {
609 			*type = THERMAL_TRIP_HOT;
610 			return 0;
611 		}
612 		trip--;
613 	}
614 
615 	if (tz->trips.passive.flags.valid) {
616 		if (!trip) {
617 			*type = THERMAL_TRIP_PASSIVE;
618 			return 0;
619 		}
620 		trip--;
621 	}
622 
623 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE &&
624 		tz->trips.active[i].flags.valid; i++) {
625 		if (!trip) {
626 			*type = THERMAL_TRIP_ACTIVE;
627 			return 0;
628 		}
629 		trip--;
630 	}
631 
632 	return -EINVAL;
633 }
634 
635 static int thermal_get_trip_temp(struct thermal_zone_device *thermal,
636 				 int trip, int *temp)
637 {
638 	struct acpi_thermal *tz = thermal->devdata;
639 	int i;
640 
641 	if (!tz || trip < 0)
642 		return -EINVAL;
643 
644 	if (tz->trips.critical.flags.valid) {
645 		if (!trip) {
646 			*temp = DECI_KELVIN_TO_MILLICELSIUS_WITH_OFFSET(
647 				tz->trips.critical.temperature,
648 				tz->kelvin_offset);
649 			return 0;
650 		}
651 		trip--;
652 	}
653 
654 	if (tz->trips.hot.flags.valid) {
655 		if (!trip) {
656 			*temp = DECI_KELVIN_TO_MILLICELSIUS_WITH_OFFSET(
657 				tz->trips.hot.temperature,
658 				tz->kelvin_offset);
659 			return 0;
660 		}
661 		trip--;
662 	}
663 
664 	if (tz->trips.passive.flags.valid) {
665 		if (!trip) {
666 			*temp = DECI_KELVIN_TO_MILLICELSIUS_WITH_OFFSET(
667 				tz->trips.passive.temperature,
668 				tz->kelvin_offset);
669 			return 0;
670 		}
671 		trip--;
672 	}
673 
674 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE &&
675 		tz->trips.active[i].flags.valid; i++) {
676 		if (!trip) {
677 			*temp = DECI_KELVIN_TO_MILLICELSIUS_WITH_OFFSET(
678 				tz->trips.active[i].temperature,
679 				tz->kelvin_offset);
680 			return 0;
681 		}
682 		trip--;
683 	}
684 
685 	return -EINVAL;
686 }
687 
688 static int thermal_get_crit_temp(struct thermal_zone_device *thermal,
689 				int *temperature)
690 {
691 	struct acpi_thermal *tz = thermal->devdata;
692 
693 	if (tz->trips.critical.flags.valid) {
694 		*temperature = DECI_KELVIN_TO_MILLICELSIUS_WITH_OFFSET(
695 				tz->trips.critical.temperature,
696 				tz->kelvin_offset);
697 		return 0;
698 	} else
699 		return -EINVAL;
700 }
701 
702 static int thermal_get_trend(struct thermal_zone_device *thermal,
703 				int trip, enum thermal_trend *trend)
704 {
705 	struct acpi_thermal *tz = thermal->devdata;
706 	enum thermal_trip_type type;
707 	int i;
708 
709 	if (thermal_get_trip_type(thermal, trip, &type))
710 		return -EINVAL;
711 
712 	if (type == THERMAL_TRIP_ACTIVE) {
713 		int trip_temp;
714 		int temp = DECI_KELVIN_TO_MILLICELSIUS_WITH_OFFSET(
715 					tz->temperature, tz->kelvin_offset);
716 		if (thermal_get_trip_temp(thermal, trip, &trip_temp))
717 			return -EINVAL;
718 
719 		if (temp > trip_temp) {
720 			*trend = THERMAL_TREND_RAISING;
721 			return 0;
722 		} else {
723 			/* Fall back on default trend */
724 			return -EINVAL;
725 		}
726 	}
727 
728 	/*
729 	 * tz->temperature has already been updated by generic thermal layer,
730 	 * before this callback being invoked
731 	 */
732 	i = (tz->trips.passive.tc1 * (tz->temperature - tz->last_temperature))
733 		+ (tz->trips.passive.tc2
734 		* (tz->temperature - tz->trips.passive.temperature));
735 
736 	if (i > 0)
737 		*trend = THERMAL_TREND_RAISING;
738 	else if (i < 0)
739 		*trend = THERMAL_TREND_DROPPING;
740 	else
741 		*trend = THERMAL_TREND_STABLE;
742 	return 0;
743 }
744 
745 
746 static int thermal_notify(struct thermal_zone_device *thermal, int trip,
747 			   enum thermal_trip_type trip_type)
748 {
749 	u8 type = 0;
750 	struct acpi_thermal *tz = thermal->devdata;
751 
752 	if (trip_type == THERMAL_TRIP_CRITICAL)
753 		type = ACPI_THERMAL_NOTIFY_CRITICAL;
754 	else if (trip_type == THERMAL_TRIP_HOT)
755 		type = ACPI_THERMAL_NOTIFY_HOT;
756 	else
757 		return 0;
758 
759 	acpi_bus_generate_netlink_event(tz->device->pnp.device_class,
760 					dev_name(&tz->device->dev), type, 1);
761 
762 	if (trip_type == THERMAL_TRIP_CRITICAL && nocrt)
763 		return 1;
764 
765 	return 0;
766 }
767 
768 static int acpi_thermal_cooling_device_cb(struct thermal_zone_device *thermal,
769 					struct thermal_cooling_device *cdev,
770 					bool bind)
771 {
772 	struct acpi_device *device = cdev->devdata;
773 	struct acpi_thermal *tz = thermal->devdata;
774 	struct acpi_device *dev;
775 	acpi_status status;
776 	acpi_handle handle;
777 	int i;
778 	int j;
779 	int trip = -1;
780 	int result = 0;
781 
782 	if (tz->trips.critical.flags.valid)
783 		trip++;
784 
785 	if (tz->trips.hot.flags.valid)
786 		trip++;
787 
788 	if (tz->trips.passive.flags.valid) {
789 		trip++;
790 		for (i = 0; i < tz->trips.passive.devices.count;
791 		    i++) {
792 			handle = tz->trips.passive.devices.handles[i];
793 			status = acpi_bus_get_device(handle, &dev);
794 			if (ACPI_FAILURE(status) || dev != device)
795 				continue;
796 			if (bind)
797 				result =
798 					thermal_zone_bind_cooling_device
799 					(thermal, trip, cdev,
800 					 THERMAL_NO_LIMIT, THERMAL_NO_LIMIT,
801 					 THERMAL_WEIGHT_DEFAULT);
802 			else
803 				result =
804 					thermal_zone_unbind_cooling_device
805 					(thermal, trip, cdev);
806 			if (result)
807 				goto failed;
808 		}
809 	}
810 
811 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
812 		if (!tz->trips.active[i].flags.valid)
813 			break;
814 		trip++;
815 		for (j = 0;
816 		    j < tz->trips.active[i].devices.count;
817 		    j++) {
818 			handle = tz->trips.active[i].devices.handles[j];
819 			status = acpi_bus_get_device(handle, &dev);
820 			if (ACPI_FAILURE(status) || dev != device)
821 				continue;
822 			if (bind)
823 				result = thermal_zone_bind_cooling_device
824 					(thermal, trip, cdev,
825 					 THERMAL_NO_LIMIT, THERMAL_NO_LIMIT,
826 					 THERMAL_WEIGHT_DEFAULT);
827 			else
828 				result = thermal_zone_unbind_cooling_device
829 					(thermal, trip, cdev);
830 			if (result)
831 				goto failed;
832 		}
833 	}
834 
835 	for (i = 0; i < tz->devices.count; i++) {
836 		handle = tz->devices.handles[i];
837 		status = acpi_bus_get_device(handle, &dev);
838 		if (ACPI_SUCCESS(status) && (dev == device)) {
839 			if (bind)
840 				result = thermal_zone_bind_cooling_device
841 						(thermal, THERMAL_TRIPS_NONE,
842 						 cdev, THERMAL_NO_LIMIT,
843 						 THERMAL_NO_LIMIT,
844 						 THERMAL_WEIGHT_DEFAULT);
845 			else
846 				result = thermal_zone_unbind_cooling_device
847 						(thermal, THERMAL_TRIPS_NONE,
848 						 cdev);
849 			if (result)
850 				goto failed;
851 		}
852 	}
853 
854 failed:
855 	return result;
856 }
857 
858 static int
859 acpi_thermal_bind_cooling_device(struct thermal_zone_device *thermal,
860 					struct thermal_cooling_device *cdev)
861 {
862 	return acpi_thermal_cooling_device_cb(thermal, cdev, true);
863 }
864 
865 static int
866 acpi_thermal_unbind_cooling_device(struct thermal_zone_device *thermal,
867 					struct thermal_cooling_device *cdev)
868 {
869 	return acpi_thermal_cooling_device_cb(thermal, cdev, false);
870 }
871 
872 static struct thermal_zone_device_ops acpi_thermal_zone_ops = {
873 	.bind = acpi_thermal_bind_cooling_device,
874 	.unbind	= acpi_thermal_unbind_cooling_device,
875 	.get_temp = thermal_get_temp,
876 	.get_mode = thermal_get_mode,
877 	.set_mode = thermal_set_mode,
878 	.get_trip_type = thermal_get_trip_type,
879 	.get_trip_temp = thermal_get_trip_temp,
880 	.get_crit_temp = thermal_get_crit_temp,
881 	.get_trend = thermal_get_trend,
882 	.notify = thermal_notify,
883 };
884 
885 static int acpi_thermal_register_thermal_zone(struct acpi_thermal *tz)
886 {
887 	int trips = 0;
888 	int result;
889 	acpi_status status;
890 	int i;
891 
892 	if (tz->trips.critical.flags.valid)
893 		trips++;
894 
895 	if (tz->trips.hot.flags.valid)
896 		trips++;
897 
898 	if (tz->trips.passive.flags.valid)
899 		trips++;
900 
901 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE &&
902 			tz->trips.active[i].flags.valid; i++, trips++);
903 
904 	if (tz->trips.passive.flags.valid)
905 		tz->thermal_zone =
906 			thermal_zone_device_register("acpitz", trips, 0, tz,
907 						&acpi_thermal_zone_ops, NULL,
908 						     tz->trips.passive.tsp*100,
909 						     tz->polling_frequency*100);
910 	else
911 		tz->thermal_zone =
912 			thermal_zone_device_register("acpitz", trips, 0, tz,
913 						&acpi_thermal_zone_ops, NULL,
914 						0, tz->polling_frequency*100);
915 	if (IS_ERR(tz->thermal_zone))
916 		return -ENODEV;
917 
918 	result = sysfs_create_link(&tz->device->dev.kobj,
919 				   &tz->thermal_zone->device.kobj, "thermal_zone");
920 	if (result)
921 		return result;
922 
923 	result = sysfs_create_link(&tz->thermal_zone->device.kobj,
924 				   &tz->device->dev.kobj, "device");
925 	if (result)
926 		return result;
927 
928 	status =  acpi_bus_attach_private_data(tz->device->handle,
929 					       tz->thermal_zone);
930 	if (ACPI_FAILURE(status))
931 		return -ENODEV;
932 
933 	tz->tz_enabled = 1;
934 
935 	dev_info(&tz->device->dev, "registered as thermal_zone%d\n",
936 		 tz->thermal_zone->id);
937 	return 0;
938 }
939 
940 static void acpi_thermal_unregister_thermal_zone(struct acpi_thermal *tz)
941 {
942 	sysfs_remove_link(&tz->device->dev.kobj, "thermal_zone");
943 	sysfs_remove_link(&tz->thermal_zone->device.kobj, "device");
944 	thermal_zone_device_unregister(tz->thermal_zone);
945 	tz->thermal_zone = NULL;
946 	acpi_bus_detach_private_data(tz->device->handle);
947 }
948 
949 
950 /* --------------------------------------------------------------------------
951                                  Driver Interface
952    -------------------------------------------------------------------------- */
953 
954 static void acpi_thermal_notify(struct acpi_device *device, u32 event)
955 {
956 	struct acpi_thermal *tz = acpi_driver_data(device);
957 
958 
959 	if (!tz)
960 		return;
961 
962 	switch (event) {
963 	case ACPI_THERMAL_NOTIFY_TEMPERATURE:
964 		acpi_thermal_check(tz);
965 		break;
966 	case ACPI_THERMAL_NOTIFY_THRESHOLDS:
967 		acpi_thermal_trips_update(tz, ACPI_TRIPS_REFRESH_THRESHOLDS);
968 		acpi_thermal_check(tz);
969 		acpi_bus_generate_netlink_event(device->pnp.device_class,
970 						  dev_name(&device->dev), event, 0);
971 		break;
972 	case ACPI_THERMAL_NOTIFY_DEVICES:
973 		acpi_thermal_trips_update(tz, ACPI_TRIPS_REFRESH_DEVICES);
974 		acpi_thermal_check(tz);
975 		acpi_bus_generate_netlink_event(device->pnp.device_class,
976 						  dev_name(&device->dev), event, 0);
977 		break;
978 	default:
979 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
980 				  "Unsupported event [0x%x]\n", event));
981 		break;
982 	}
983 }
984 
985 /*
986  * On some platforms, the AML code has dependency about
987  * the evaluating order of _TMP and _CRT/_HOT/_PSV/_ACx.
988  * 1. On HP Pavilion G4-1016tx, _TMP must be invoked after
989  *    /_CRT/_HOT/_PSV/_ACx, or else system will be power off.
990  * 2. On HP Compaq 6715b/6715s, the return value of _PSV is 0
991  *    if _TMP has never been evaluated.
992  *
993  * As this dependency is totally transparent to OS, evaluate
994  * all of them once, in the order of _CRT/_HOT/_PSV/_ACx,
995  * _TMP, before they are actually used.
996  */
997 static void acpi_thermal_aml_dependency_fix(struct acpi_thermal *tz)
998 {
999 	acpi_handle handle = tz->device->handle;
1000 	unsigned long long value;
1001 	int i;
1002 
1003 	acpi_evaluate_integer(handle, "_CRT", NULL, &value);
1004 	acpi_evaluate_integer(handle, "_HOT", NULL, &value);
1005 	acpi_evaluate_integer(handle, "_PSV", NULL, &value);
1006 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
1007 		char name[5] = { '_', 'A', 'C', ('0' + i), '\0' };
1008 		acpi_status status;
1009 
1010 		status = acpi_evaluate_integer(handle, name, NULL, &value);
1011 		if (status == AE_NOT_FOUND)
1012 			break;
1013 	}
1014 	acpi_evaluate_integer(handle, "_TMP", NULL, &value);
1015 }
1016 
1017 static int acpi_thermal_get_info(struct acpi_thermal *tz)
1018 {
1019 	int result = 0;
1020 
1021 
1022 	if (!tz)
1023 		return -EINVAL;
1024 
1025 	acpi_thermal_aml_dependency_fix(tz);
1026 
1027 	/* Get trip points [_CRT, _PSV, etc.] (required) */
1028 	result = acpi_thermal_get_trip_points(tz);
1029 	if (result)
1030 		return result;
1031 
1032 	/* Get temperature [_TMP] (required) */
1033 	result = acpi_thermal_get_temperature(tz);
1034 	if (result)
1035 		return result;
1036 
1037 	/* Set the cooling mode [_SCP] to active cooling (default) */
1038 	result = acpi_thermal_set_cooling_mode(tz, ACPI_THERMAL_MODE_ACTIVE);
1039 	if (!result)
1040 		tz->flags.cooling_mode = 1;
1041 
1042 	/* Get default polling frequency [_TZP] (optional) */
1043 	if (tzp)
1044 		tz->polling_frequency = tzp;
1045 	else
1046 		acpi_thermal_get_polling_frequency(tz);
1047 
1048 	return 0;
1049 }
1050 
1051 /*
1052  * The exact offset between Kelvin and degree Celsius is 273.15. However ACPI
1053  * handles temperature values with a single decimal place. As a consequence,
1054  * some implementations use an offset of 273.1 and others use an offset of
1055  * 273.2. Try to find out which one is being used, to present the most
1056  * accurate and visually appealing number.
1057  *
1058  * The heuristic below should work for all ACPI thermal zones which have a
1059  * critical trip point with a value being a multiple of 0.5 degree Celsius.
1060  */
1061 static void acpi_thermal_guess_offset(struct acpi_thermal *tz)
1062 {
1063 	if (tz->trips.critical.flags.valid &&
1064 	    (tz->trips.critical.temperature % 5) == 1)
1065 		tz->kelvin_offset = 2731;
1066 	else
1067 		tz->kelvin_offset = 2732;
1068 }
1069 
1070 static void acpi_thermal_check_fn(struct work_struct *work)
1071 {
1072 	struct acpi_thermal *tz = container_of(work, struct acpi_thermal,
1073 					       thermal_check_work);
1074 	acpi_thermal_check(tz);
1075 }
1076 
1077 static int acpi_thermal_add(struct acpi_device *device)
1078 {
1079 	int result = 0;
1080 	struct acpi_thermal *tz = NULL;
1081 
1082 
1083 	if (!device)
1084 		return -EINVAL;
1085 
1086 	tz = kzalloc(sizeof(struct acpi_thermal), GFP_KERNEL);
1087 	if (!tz)
1088 		return -ENOMEM;
1089 
1090 	tz->device = device;
1091 	strcpy(tz->name, device->pnp.bus_id);
1092 	strcpy(acpi_device_name(device), ACPI_THERMAL_DEVICE_NAME);
1093 	strcpy(acpi_device_class(device), ACPI_THERMAL_CLASS);
1094 	device->driver_data = tz;
1095 
1096 	result = acpi_thermal_get_info(tz);
1097 	if (result)
1098 		goto free_memory;
1099 
1100 	acpi_thermal_guess_offset(tz);
1101 
1102 	result = acpi_thermal_register_thermal_zone(tz);
1103 	if (result)
1104 		goto free_memory;
1105 
1106 	INIT_WORK(&tz->thermal_check_work, acpi_thermal_check_fn);
1107 
1108 	pr_info(PREFIX "%s [%s] (%ld C)\n", acpi_device_name(device),
1109 		acpi_device_bid(device), DECI_KELVIN_TO_CELSIUS(tz->temperature));
1110 	goto end;
1111 
1112 free_memory:
1113 	kfree(tz);
1114 end:
1115 	return result;
1116 }
1117 
1118 static int acpi_thermal_remove(struct acpi_device *device)
1119 {
1120 	struct acpi_thermal *tz = NULL;
1121 
1122 	if (!device || !acpi_driver_data(device))
1123 		return -EINVAL;
1124 
1125 	flush_workqueue(acpi_thermal_pm_queue);
1126 	tz = acpi_driver_data(device);
1127 
1128 	acpi_thermal_unregister_thermal_zone(tz);
1129 	kfree(tz);
1130 	return 0;
1131 }
1132 
1133 #ifdef CONFIG_PM_SLEEP
1134 static int acpi_thermal_suspend(struct device *dev)
1135 {
1136 	/* Make sure the previously queued thermal check work has been done */
1137 	flush_workqueue(acpi_thermal_pm_queue);
1138 	return 0;
1139 }
1140 
1141 static int acpi_thermal_resume(struct device *dev)
1142 {
1143 	struct acpi_thermal *tz;
1144 	int i, j, power_state, result;
1145 
1146 	if (!dev)
1147 		return -EINVAL;
1148 
1149 	tz = acpi_driver_data(to_acpi_device(dev));
1150 	if (!tz)
1151 		return -EINVAL;
1152 
1153 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
1154 		if (!(&tz->trips.active[i]))
1155 			break;
1156 		if (!tz->trips.active[i].flags.valid)
1157 			break;
1158 		tz->trips.active[i].flags.enabled = 1;
1159 		for (j = 0; j < tz->trips.active[i].devices.count; j++) {
1160 			result = acpi_bus_update_power(
1161 					tz->trips.active[i].devices.handles[j],
1162 					&power_state);
1163 			if (result || (power_state != ACPI_STATE_D0)) {
1164 				tz->trips.active[i].flags.enabled = 0;
1165 				break;
1166 			}
1167 		}
1168 		tz->state.active |= tz->trips.active[i].flags.enabled;
1169 	}
1170 
1171 	queue_work(acpi_thermal_pm_queue, &tz->thermal_check_work);
1172 
1173 	return AE_OK;
1174 }
1175 #endif
1176 
1177 static int thermal_act(const struct dmi_system_id *d) {
1178 
1179 	if (act == 0) {
1180 		pr_notice(PREFIX "%s detected: "
1181 			  "disabling all active thermal trip points\n", d->ident);
1182 		act = -1;
1183 	}
1184 	return 0;
1185 }
1186 static int thermal_nocrt(const struct dmi_system_id *d) {
1187 
1188 	pr_notice(PREFIX "%s detected: "
1189 		  "disabling all critical thermal trip point actions.\n", d->ident);
1190 	nocrt = 1;
1191 	return 0;
1192 }
1193 static int thermal_tzp(const struct dmi_system_id *d) {
1194 
1195 	if (tzp == 0) {
1196 		pr_notice(PREFIX "%s detected: "
1197 			  "enabling thermal zone polling\n", d->ident);
1198 		tzp = 300;	/* 300 dS = 30 Seconds */
1199 	}
1200 	return 0;
1201 }
1202 static int thermal_psv(const struct dmi_system_id *d) {
1203 
1204 	if (psv == 0) {
1205 		pr_notice(PREFIX "%s detected: "
1206 			  "disabling all passive thermal trip points\n", d->ident);
1207 		psv = -1;
1208 	}
1209 	return 0;
1210 }
1211 
1212 static const struct dmi_system_id thermal_dmi_table[] __initconst = {
1213 	/*
1214 	 * Award BIOS on this AOpen makes thermal control almost worthless.
1215 	 * http://bugzilla.kernel.org/show_bug.cgi?id=8842
1216 	 */
1217 	{
1218 	 .callback = thermal_act,
1219 	 .ident = "AOpen i915GMm-HFS",
1220 	 .matches = {
1221 		DMI_MATCH(DMI_BOARD_VENDOR, "AOpen"),
1222 		DMI_MATCH(DMI_BOARD_NAME, "i915GMm-HFS"),
1223 		},
1224 	},
1225 	{
1226 	 .callback = thermal_psv,
1227 	 .ident = "AOpen i915GMm-HFS",
1228 	 .matches = {
1229 		DMI_MATCH(DMI_BOARD_VENDOR, "AOpen"),
1230 		DMI_MATCH(DMI_BOARD_NAME, "i915GMm-HFS"),
1231 		},
1232 	},
1233 	{
1234 	 .callback = thermal_tzp,
1235 	 .ident = "AOpen i915GMm-HFS",
1236 	 .matches = {
1237 		DMI_MATCH(DMI_BOARD_VENDOR, "AOpen"),
1238 		DMI_MATCH(DMI_BOARD_NAME, "i915GMm-HFS"),
1239 		},
1240 	},
1241 	{
1242 	 .callback = thermal_nocrt,
1243 	 .ident = "Gigabyte GA-7ZX",
1244 	 .matches = {
1245 		DMI_MATCH(DMI_BOARD_VENDOR, "Gigabyte Technology Co., Ltd."),
1246 		DMI_MATCH(DMI_BOARD_NAME, "7ZX"),
1247 		},
1248 	},
1249 	{}
1250 };
1251 
1252 static int __init acpi_thermal_init(void)
1253 {
1254 	int result = 0;
1255 
1256 	dmi_check_system(thermal_dmi_table);
1257 
1258 	if (off) {
1259 		pr_notice(PREFIX "thermal control disabled\n");
1260 		return -ENODEV;
1261 	}
1262 
1263 	acpi_thermal_pm_queue = alloc_workqueue("acpi_thermal_pm",
1264 						WQ_HIGHPRI | WQ_MEM_RECLAIM, 0);
1265 	if (!acpi_thermal_pm_queue)
1266 		return -ENODEV;
1267 
1268 	result = acpi_bus_register_driver(&acpi_thermal_driver);
1269 	if (result < 0) {
1270 		destroy_workqueue(acpi_thermal_pm_queue);
1271 		return -ENODEV;
1272 	}
1273 
1274 	return 0;
1275 }
1276 
1277 static void __exit acpi_thermal_exit(void)
1278 {
1279 	acpi_bus_unregister_driver(&acpi_thermal_driver);
1280 	destroy_workqueue(acpi_thermal_pm_queue);
1281 
1282 	return;
1283 }
1284 
1285 module_init(acpi_thermal_init);
1286 module_exit(acpi_thermal_exit);
1287