xref: /linux/drivers/acpi/thermal.c (revision be58f7103700a68d5c7ca60a2bc0b309907599ab)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  acpi_thermal.c - ACPI Thermal Zone Driver ($Revision: 41 $)
4  *
5  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
6  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
7  *
8  *  This driver fully implements the ACPI thermal policy as described in the
9  *  ACPI 2.0 Specification.
10  *
11  *  TBD: 1. Implement passive cooling hysteresis.
12  *       2. Enhance passive cooling (CPU) states/limit interface to support
13  *          concepts of 'multiple limiters', upper/lower limits, etc.
14  */
15 
16 #define pr_fmt(fmt) "ACPI: thermal: " fmt
17 
18 #include <linux/kernel.h>
19 #include <linux/module.h>
20 #include <linux/dmi.h>
21 #include <linux/init.h>
22 #include <linux/slab.h>
23 #include <linux/types.h>
24 #include <linux/jiffies.h>
25 #include <linux/kmod.h>
26 #include <linux/reboot.h>
27 #include <linux/device.h>
28 #include <linux/thermal.h>
29 #include <linux/acpi.h>
30 #include <linux/workqueue.h>
31 #include <linux/uaccess.h>
32 #include <linux/units.h>
33 
34 #define ACPI_THERMAL_CLASS		"thermal_zone"
35 #define ACPI_THERMAL_DEVICE_NAME	"Thermal Zone"
36 #define ACPI_THERMAL_NOTIFY_TEMPERATURE	0x80
37 #define ACPI_THERMAL_NOTIFY_THRESHOLDS	0x81
38 #define ACPI_THERMAL_NOTIFY_DEVICES	0x82
39 #define ACPI_THERMAL_NOTIFY_CRITICAL	0xF0
40 #define ACPI_THERMAL_NOTIFY_HOT		0xF1
41 #define ACPI_THERMAL_MODE_ACTIVE	0x00
42 
43 #define ACPI_THERMAL_MAX_ACTIVE	10
44 #define ACPI_THERMAL_MAX_LIMIT_STR_LEN 65
45 
46 MODULE_AUTHOR("Paul Diefenbaugh");
47 MODULE_DESCRIPTION("ACPI Thermal Zone Driver");
48 MODULE_LICENSE("GPL");
49 
50 static int act;
51 module_param(act, int, 0644);
52 MODULE_PARM_DESC(act, "Disable or override all lowest active trip points.");
53 
54 static int crt;
55 module_param(crt, int, 0644);
56 MODULE_PARM_DESC(crt, "Disable or lower all critical trip points.");
57 
58 static int tzp;
59 module_param(tzp, int, 0444);
60 MODULE_PARM_DESC(tzp, "Thermal zone polling frequency, in 1/10 seconds.");
61 
62 static int nocrt;
63 module_param(nocrt, int, 0);
64 MODULE_PARM_DESC(nocrt, "Set to take no action upon ACPI thermal zone critical trips points.");
65 
66 static int off;
67 module_param(off, int, 0);
68 MODULE_PARM_DESC(off, "Set to disable ACPI thermal support.");
69 
70 static int psv;
71 module_param(psv, int, 0644);
72 MODULE_PARM_DESC(psv, "Disable or override all passive trip points.");
73 
74 static struct workqueue_struct *acpi_thermal_pm_queue;
75 
76 static int acpi_thermal_add(struct acpi_device *device);
77 static int acpi_thermal_remove(struct acpi_device *device);
78 static void acpi_thermal_notify(struct acpi_device *device, u32 event);
79 
80 static const struct acpi_device_id  thermal_device_ids[] = {
81 	{ACPI_THERMAL_HID, 0},
82 	{"", 0},
83 };
84 MODULE_DEVICE_TABLE(acpi, thermal_device_ids);
85 
86 #ifdef CONFIG_PM_SLEEP
87 static int acpi_thermal_suspend(struct device *dev);
88 static int acpi_thermal_resume(struct device *dev);
89 #else
90 #define acpi_thermal_suspend NULL
91 #define acpi_thermal_resume NULL
92 #endif
93 static SIMPLE_DEV_PM_OPS(acpi_thermal_pm, acpi_thermal_suspend, acpi_thermal_resume);
94 
95 static struct acpi_driver acpi_thermal_driver = {
96 	.name = "thermal",
97 	.class = ACPI_THERMAL_CLASS,
98 	.ids = thermal_device_ids,
99 	.ops = {
100 		.add = acpi_thermal_add,
101 		.remove = acpi_thermal_remove,
102 		.notify = acpi_thermal_notify,
103 		},
104 	.drv.pm = &acpi_thermal_pm,
105 };
106 
107 struct acpi_thermal_state {
108 	u8 critical:1;
109 	u8 hot:1;
110 	u8 passive:1;
111 	u8 active:1;
112 	u8 reserved:4;
113 	int active_index;
114 };
115 
116 struct acpi_thermal_state_flags {
117 	u8 valid:1;
118 	u8 enabled:1;
119 	u8 reserved:6;
120 };
121 
122 struct acpi_thermal_critical {
123 	struct acpi_thermal_state_flags flags;
124 	unsigned long temperature;
125 };
126 
127 struct acpi_thermal_hot {
128 	struct acpi_thermal_state_flags flags;
129 	unsigned long temperature;
130 };
131 
132 struct acpi_thermal_passive {
133 	struct acpi_thermal_state_flags flags;
134 	unsigned long temperature;
135 	unsigned long tc1;
136 	unsigned long tc2;
137 	unsigned long tsp;
138 	struct acpi_handle_list devices;
139 };
140 
141 struct acpi_thermal_active {
142 	struct acpi_thermal_state_flags flags;
143 	unsigned long temperature;
144 	struct acpi_handle_list devices;
145 };
146 
147 struct acpi_thermal_trips {
148 	struct acpi_thermal_critical critical;
149 	struct acpi_thermal_hot hot;
150 	struct acpi_thermal_passive passive;
151 	struct acpi_thermal_active active[ACPI_THERMAL_MAX_ACTIVE];
152 };
153 
154 struct acpi_thermal_flags {
155 	u8 cooling_mode:1;	/* _SCP */
156 	u8 devices:1;		/* _TZD */
157 	u8 reserved:6;
158 };
159 
160 struct acpi_thermal {
161 	struct acpi_device * device;
162 	acpi_bus_id name;
163 	unsigned long temperature;
164 	unsigned long last_temperature;
165 	unsigned long polling_frequency;
166 	volatile u8 zombie;
167 	struct acpi_thermal_flags flags;
168 	struct acpi_thermal_state state;
169 	struct acpi_thermal_trips trips;
170 	struct acpi_handle_list devices;
171 	struct thermal_zone_device *thermal_zone;
172 	int kelvin_offset;	/* in millidegrees */
173 	struct work_struct thermal_check_work;
174 	struct mutex thermal_check_lock;
175 	refcount_t thermal_check_count;
176 };
177 
178 /* --------------------------------------------------------------------------
179                              Thermal Zone Management
180    -------------------------------------------------------------------------- */
181 
182 static int acpi_thermal_get_temperature(struct acpi_thermal *tz)
183 {
184 	acpi_status status = AE_OK;
185 	unsigned long long tmp;
186 
187 	if (!tz)
188 		return -EINVAL;
189 
190 	tz->last_temperature = tz->temperature;
191 
192 	status = acpi_evaluate_integer(tz->device->handle, "_TMP", NULL, &tmp);
193 	if (ACPI_FAILURE(status))
194 		return -ENODEV;
195 
196 	tz->temperature = tmp;
197 
198 	acpi_handle_debug(tz->device->handle, "Temperature is %lu dK\n",
199 			  tz->temperature);
200 
201 	return 0;
202 }
203 
204 static int acpi_thermal_get_polling_frequency(struct acpi_thermal *tz)
205 {
206 	acpi_status status = AE_OK;
207 	unsigned long long tmp;
208 
209 	if (!tz)
210 		return -EINVAL;
211 
212 	status = acpi_evaluate_integer(tz->device->handle, "_TZP", NULL, &tmp);
213 	if (ACPI_FAILURE(status))
214 		return -ENODEV;
215 
216 	tz->polling_frequency = tmp;
217 	acpi_handle_debug(tz->device->handle, "Polling frequency is %lu dS\n",
218 			  tz->polling_frequency);
219 
220 	return 0;
221 }
222 
223 static int acpi_thermal_set_cooling_mode(struct acpi_thermal *tz, int mode)
224 {
225 	if (!tz)
226 		return -EINVAL;
227 
228 	if (ACPI_FAILURE(acpi_execute_simple_method(tz->device->handle,
229 						    "_SCP", mode)))
230 		return -ENODEV;
231 
232 	return 0;
233 }
234 
235 #define ACPI_TRIPS_CRITICAL	0x01
236 #define ACPI_TRIPS_HOT		0x02
237 #define ACPI_TRIPS_PASSIVE	0x04
238 #define ACPI_TRIPS_ACTIVE	0x08
239 #define ACPI_TRIPS_DEVICES	0x10
240 
241 #define ACPI_TRIPS_REFRESH_THRESHOLDS	(ACPI_TRIPS_PASSIVE | ACPI_TRIPS_ACTIVE)
242 #define ACPI_TRIPS_REFRESH_DEVICES	ACPI_TRIPS_DEVICES
243 
244 #define ACPI_TRIPS_INIT      (ACPI_TRIPS_CRITICAL | ACPI_TRIPS_HOT |	\
245 			      ACPI_TRIPS_PASSIVE | ACPI_TRIPS_ACTIVE |	\
246 			      ACPI_TRIPS_DEVICES)
247 
248 /*
249  * This exception is thrown out in two cases:
250  * 1.An invalid trip point becomes invalid or a valid trip point becomes invalid
251  *   when re-evaluating the AML code.
252  * 2.TODO: Devices listed in _PSL, _ALx, _TZD may change.
253  *   We need to re-bind the cooling devices of a thermal zone when this occurs.
254  */
255 #define ACPI_THERMAL_TRIPS_EXCEPTION(flags, tz, str)	\
256 do {	\
257 	if (flags != ACPI_TRIPS_INIT)	\
258 		acpi_handle_info(tz->device->handle,	\
259 		"ACPI thermal trip point %s changed\n"	\
260 		"Please report to linux-acpi@vger.kernel.org\n", str); \
261 } while (0)
262 
263 static int acpi_thermal_trips_update(struct acpi_thermal *tz, int flag)
264 {
265 	acpi_status status = AE_OK;
266 	unsigned long long tmp;
267 	struct acpi_handle_list devices;
268 	int valid = 0;
269 	int i;
270 
271 	/* Critical Shutdown */
272 	if (flag & ACPI_TRIPS_CRITICAL) {
273 		status = acpi_evaluate_integer(tz->device->handle,
274 				"_CRT", NULL, &tmp);
275 		tz->trips.critical.temperature = tmp;
276 		/*
277 		 * Treat freezing temperatures as invalid as well; some
278 		 * BIOSes return really low values and cause reboots at startup.
279 		 * Below zero (Celsius) values clearly aren't right for sure..
280 		 * ... so lets discard those as invalid.
281 		 */
282 		if (ACPI_FAILURE(status)) {
283 			tz->trips.critical.flags.valid = 0;
284 			acpi_handle_debug(tz->device->handle,
285 					  "No critical threshold\n");
286 		} else if (tmp <= 2732) {
287 			pr_info(FW_BUG "Invalid critical threshold (%llu)\n",
288 				tmp);
289 			tz->trips.critical.flags.valid = 0;
290 		} else {
291 			tz->trips.critical.flags.valid = 1;
292 			acpi_handle_debug(tz->device->handle,
293 					  "Found critical threshold [%lu]\n",
294 					  tz->trips.critical.temperature);
295 		}
296 		if (tz->trips.critical.flags.valid == 1) {
297 			if (crt == -1) {
298 				tz->trips.critical.flags.valid = 0;
299 			} else if (crt > 0) {
300 				unsigned long crt_k = celsius_to_deci_kelvin(crt);
301 
302 				/*
303 				 * Allow override critical threshold
304 				 */
305 				if (crt_k > tz->trips.critical.temperature)
306 					pr_info("Critical threshold %d C\n", crt);
307 
308 				tz->trips.critical.temperature = crt_k;
309 			}
310 		}
311 	}
312 
313 	/* Critical Sleep (optional) */
314 	if (flag & ACPI_TRIPS_HOT) {
315 		status = acpi_evaluate_integer(tz->device->handle,
316 				"_HOT", NULL, &tmp);
317 		if (ACPI_FAILURE(status)) {
318 			tz->trips.hot.flags.valid = 0;
319 			acpi_handle_debug(tz->device->handle,
320 					  "No hot threshold\n");
321 		} else {
322 			tz->trips.hot.temperature = tmp;
323 			tz->trips.hot.flags.valid = 1;
324 			acpi_handle_debug(tz->device->handle,
325 					  "Found hot threshold [%lu]\n",
326 					  tz->trips.hot.temperature);
327 		}
328 	}
329 
330 	/* Passive (optional) */
331 	if (((flag & ACPI_TRIPS_PASSIVE) && tz->trips.passive.flags.valid) ||
332 		(flag == ACPI_TRIPS_INIT)) {
333 		valid = tz->trips.passive.flags.valid;
334 		if (psv == -1) {
335 			status = AE_SUPPORT;
336 		} else if (psv > 0) {
337 			tmp = celsius_to_deci_kelvin(psv);
338 			status = AE_OK;
339 		} else {
340 			status = acpi_evaluate_integer(tz->device->handle,
341 				"_PSV", NULL, &tmp);
342 		}
343 
344 		if (ACPI_FAILURE(status))
345 			tz->trips.passive.flags.valid = 0;
346 		else {
347 			tz->trips.passive.temperature = tmp;
348 			tz->trips.passive.flags.valid = 1;
349 			if (flag == ACPI_TRIPS_INIT) {
350 				status = acpi_evaluate_integer(
351 						tz->device->handle, "_TC1",
352 						NULL, &tmp);
353 				if (ACPI_FAILURE(status))
354 					tz->trips.passive.flags.valid = 0;
355 				else
356 					tz->trips.passive.tc1 = tmp;
357 				status = acpi_evaluate_integer(
358 						tz->device->handle, "_TC2",
359 						NULL, &tmp);
360 				if (ACPI_FAILURE(status))
361 					tz->trips.passive.flags.valid = 0;
362 				else
363 					tz->trips.passive.tc2 = tmp;
364 				status = acpi_evaluate_integer(
365 						tz->device->handle, "_TSP",
366 						NULL, &tmp);
367 				if (ACPI_FAILURE(status))
368 					tz->trips.passive.flags.valid = 0;
369 				else
370 					tz->trips.passive.tsp = tmp;
371 			}
372 		}
373 	}
374 	if ((flag & ACPI_TRIPS_DEVICES) && tz->trips.passive.flags.valid) {
375 		memset(&devices, 0, sizeof(struct acpi_handle_list));
376 		status = acpi_evaluate_reference(tz->device->handle, "_PSL",
377 							NULL, &devices);
378 		if (ACPI_FAILURE(status)) {
379 			acpi_handle_info(tz->device->handle,
380 					 "Invalid passive threshold\n");
381 			tz->trips.passive.flags.valid = 0;
382 		}
383 		else
384 			tz->trips.passive.flags.valid = 1;
385 
386 		if (memcmp(&tz->trips.passive.devices, &devices,
387 				sizeof(struct acpi_handle_list))) {
388 			memcpy(&tz->trips.passive.devices, &devices,
389 				sizeof(struct acpi_handle_list));
390 			ACPI_THERMAL_TRIPS_EXCEPTION(flag, tz, "device");
391 		}
392 	}
393 	if ((flag & ACPI_TRIPS_PASSIVE) || (flag & ACPI_TRIPS_DEVICES)) {
394 		if (valid != tz->trips.passive.flags.valid)
395 				ACPI_THERMAL_TRIPS_EXCEPTION(flag, tz, "state");
396 	}
397 
398 	/* Active (optional) */
399 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
400 		char name[5] = { '_', 'A', 'C', ('0' + i), '\0' };
401 		valid = tz->trips.active[i].flags.valid;
402 
403 		if (act == -1)
404 			break; /* disable all active trip points */
405 
406 		if ((flag == ACPI_TRIPS_INIT) || ((flag & ACPI_TRIPS_ACTIVE) &&
407 			tz->trips.active[i].flags.valid)) {
408 			status = acpi_evaluate_integer(tz->device->handle,
409 							name, NULL, &tmp);
410 			if (ACPI_FAILURE(status)) {
411 				tz->trips.active[i].flags.valid = 0;
412 				if (i == 0)
413 					break;
414 				if (act <= 0)
415 					break;
416 				if (i == 1)
417 					tz->trips.active[0].temperature =
418 						celsius_to_deci_kelvin(act);
419 				else
420 					/*
421 					 * Don't allow override higher than
422 					 * the next higher trip point
423 					 */
424 					tz->trips.active[i - 1].temperature =
425 						(tz->trips.active[i - 2].temperature <
426 						celsius_to_deci_kelvin(act) ?
427 						tz->trips.active[i - 2].temperature :
428 						celsius_to_deci_kelvin(act));
429 				break;
430 			} else {
431 				tz->trips.active[i].temperature = tmp;
432 				tz->trips.active[i].flags.valid = 1;
433 			}
434 		}
435 
436 		name[2] = 'L';
437 		if ((flag & ACPI_TRIPS_DEVICES) && tz->trips.active[i].flags.valid ) {
438 			memset(&devices, 0, sizeof(struct acpi_handle_list));
439 			status = acpi_evaluate_reference(tz->device->handle,
440 						name, NULL, &devices);
441 			if (ACPI_FAILURE(status)) {
442 				acpi_handle_info(tz->device->handle,
443 						 "Invalid active%d threshold\n", i);
444 				tz->trips.active[i].flags.valid = 0;
445 			}
446 			else
447 				tz->trips.active[i].flags.valid = 1;
448 
449 			if (memcmp(&tz->trips.active[i].devices, &devices,
450 					sizeof(struct acpi_handle_list))) {
451 				memcpy(&tz->trips.active[i].devices, &devices,
452 					sizeof(struct acpi_handle_list));
453 				ACPI_THERMAL_TRIPS_EXCEPTION(flag, tz, "device");
454 			}
455 		}
456 		if ((flag & ACPI_TRIPS_ACTIVE) || (flag & ACPI_TRIPS_DEVICES))
457 			if (valid != tz->trips.active[i].flags.valid)
458 				ACPI_THERMAL_TRIPS_EXCEPTION(flag, tz, "state");
459 
460 		if (!tz->trips.active[i].flags.valid)
461 			break;
462 	}
463 
464 	if (flag & ACPI_TRIPS_DEVICES) {
465 		memset(&devices, 0, sizeof(devices));
466 		status = acpi_evaluate_reference(tz->device->handle, "_TZD",
467 						NULL, &devices);
468 		if (ACPI_SUCCESS(status)
469 		    && memcmp(&tz->devices, &devices, sizeof(devices))) {
470 			tz->devices = devices;
471 			ACPI_THERMAL_TRIPS_EXCEPTION(flag, tz, "device");
472 		}
473 	}
474 
475 	return 0;
476 }
477 
478 static int acpi_thermal_get_trip_points(struct acpi_thermal *tz)
479 {
480 	int i, valid, ret = acpi_thermal_trips_update(tz, ACPI_TRIPS_INIT);
481 
482 	if (ret)
483 		return ret;
484 
485 	valid = tz->trips.critical.flags.valid |
486 		tz->trips.hot.flags.valid |
487 		tz->trips.passive.flags.valid;
488 
489 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++)
490 		valid |= tz->trips.active[i].flags.valid;
491 
492 	if (!valid) {
493 		pr_warn(FW_BUG "No valid trip found\n");
494 		return -ENODEV;
495 	}
496 	return 0;
497 }
498 
499 /* sys I/F for generic thermal sysfs support */
500 
501 static int thermal_get_temp(struct thermal_zone_device *thermal, int *temp)
502 {
503 	struct acpi_thermal *tz = thermal->devdata;
504 	int result;
505 
506 	if (!tz)
507 		return -EINVAL;
508 
509 	result = acpi_thermal_get_temperature(tz);
510 	if (result)
511 		return result;
512 
513 	*temp = deci_kelvin_to_millicelsius_with_offset(tz->temperature,
514 							tz->kelvin_offset);
515 	return 0;
516 }
517 
518 static int thermal_get_trip_type(struct thermal_zone_device *thermal,
519 				 int trip, enum thermal_trip_type *type)
520 {
521 	struct acpi_thermal *tz = thermal->devdata;
522 	int i;
523 
524 	if (!tz || trip < 0)
525 		return -EINVAL;
526 
527 	if (tz->trips.critical.flags.valid) {
528 		if (!trip) {
529 			*type = THERMAL_TRIP_CRITICAL;
530 			return 0;
531 		}
532 		trip--;
533 	}
534 
535 	if (tz->trips.hot.flags.valid) {
536 		if (!trip) {
537 			*type = THERMAL_TRIP_HOT;
538 			return 0;
539 		}
540 		trip--;
541 	}
542 
543 	if (tz->trips.passive.flags.valid) {
544 		if (!trip) {
545 			*type = THERMAL_TRIP_PASSIVE;
546 			return 0;
547 		}
548 		trip--;
549 	}
550 
551 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE &&
552 		tz->trips.active[i].flags.valid; i++) {
553 		if (!trip) {
554 			*type = THERMAL_TRIP_ACTIVE;
555 			return 0;
556 		}
557 		trip--;
558 	}
559 
560 	return -EINVAL;
561 }
562 
563 static int thermal_get_trip_temp(struct thermal_zone_device *thermal,
564 				 int trip, int *temp)
565 {
566 	struct acpi_thermal *tz = thermal->devdata;
567 	int i;
568 
569 	if (!tz || trip < 0)
570 		return -EINVAL;
571 
572 	if (tz->trips.critical.flags.valid) {
573 		if (!trip) {
574 			*temp = deci_kelvin_to_millicelsius_with_offset(
575 				tz->trips.critical.temperature,
576 				tz->kelvin_offset);
577 			return 0;
578 		}
579 		trip--;
580 	}
581 
582 	if (tz->trips.hot.flags.valid) {
583 		if (!trip) {
584 			*temp = deci_kelvin_to_millicelsius_with_offset(
585 				tz->trips.hot.temperature,
586 				tz->kelvin_offset);
587 			return 0;
588 		}
589 		trip--;
590 	}
591 
592 	if (tz->trips.passive.flags.valid) {
593 		if (!trip) {
594 			*temp = deci_kelvin_to_millicelsius_with_offset(
595 				tz->trips.passive.temperature,
596 				tz->kelvin_offset);
597 			return 0;
598 		}
599 		trip--;
600 	}
601 
602 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE &&
603 		tz->trips.active[i].flags.valid; i++) {
604 		if (!trip) {
605 			*temp = deci_kelvin_to_millicelsius_with_offset(
606 				tz->trips.active[i].temperature,
607 				tz->kelvin_offset);
608 			return 0;
609 		}
610 		trip--;
611 	}
612 
613 	return -EINVAL;
614 }
615 
616 static int thermal_get_crit_temp(struct thermal_zone_device *thermal,
617 				int *temperature)
618 {
619 	struct acpi_thermal *tz = thermal->devdata;
620 
621 	if (tz->trips.critical.flags.valid) {
622 		*temperature = deci_kelvin_to_millicelsius_with_offset(
623 				tz->trips.critical.temperature,
624 				tz->kelvin_offset);
625 		return 0;
626 	} else
627 		return -EINVAL;
628 }
629 
630 static int thermal_get_trend(struct thermal_zone_device *thermal,
631 				int trip, enum thermal_trend *trend)
632 {
633 	struct acpi_thermal *tz = thermal->devdata;
634 	enum thermal_trip_type type;
635 	int i;
636 
637 	if (thermal_get_trip_type(thermal, trip, &type))
638 		return -EINVAL;
639 
640 	if (type == THERMAL_TRIP_ACTIVE) {
641 		int trip_temp;
642 		int temp = deci_kelvin_to_millicelsius_with_offset(
643 					tz->temperature, tz->kelvin_offset);
644 		if (thermal_get_trip_temp(thermal, trip, &trip_temp))
645 			return -EINVAL;
646 
647 		if (temp > trip_temp) {
648 			*trend = THERMAL_TREND_RAISING;
649 			return 0;
650 		} else {
651 			/* Fall back on default trend */
652 			return -EINVAL;
653 		}
654 	}
655 
656 	/*
657 	 * tz->temperature has already been updated by generic thermal layer,
658 	 * before this callback being invoked
659 	 */
660 	i = (tz->trips.passive.tc1 * (tz->temperature - tz->last_temperature))
661 		+ (tz->trips.passive.tc2
662 		* (tz->temperature - tz->trips.passive.temperature));
663 
664 	if (i > 0)
665 		*trend = THERMAL_TREND_RAISING;
666 	else if (i < 0)
667 		*trend = THERMAL_TREND_DROPPING;
668 	else
669 		*trend = THERMAL_TREND_STABLE;
670 	return 0;
671 }
672 
673 static void acpi_thermal_zone_device_hot(struct thermal_zone_device *thermal)
674 {
675 	struct acpi_thermal *tz = thermal->devdata;
676 
677 	acpi_bus_generate_netlink_event(tz->device->pnp.device_class,
678 					dev_name(&tz->device->dev),
679 					ACPI_THERMAL_NOTIFY_HOT, 1);
680 }
681 
682 static void acpi_thermal_zone_device_critical(struct thermal_zone_device *thermal)
683 {
684 	struct acpi_thermal *tz = thermal->devdata;
685 
686 	acpi_bus_generate_netlink_event(tz->device->pnp.device_class,
687 					dev_name(&tz->device->dev),
688 					ACPI_THERMAL_NOTIFY_CRITICAL, 1);
689 
690 	thermal_zone_device_critical(thermal);
691 }
692 
693 static int acpi_thermal_cooling_device_cb(struct thermal_zone_device *thermal,
694 					struct thermal_cooling_device *cdev,
695 					bool bind)
696 {
697 	struct acpi_device *device = cdev->devdata;
698 	struct acpi_thermal *tz = thermal->devdata;
699 	struct acpi_device *dev;
700 	acpi_status status;
701 	acpi_handle handle;
702 	int i;
703 	int j;
704 	int trip = -1;
705 	int result = 0;
706 
707 	if (tz->trips.critical.flags.valid)
708 		trip++;
709 
710 	if (tz->trips.hot.flags.valid)
711 		trip++;
712 
713 	if (tz->trips.passive.flags.valid) {
714 		trip++;
715 		for (i = 0; i < tz->trips.passive.devices.count;
716 		    i++) {
717 			handle = tz->trips.passive.devices.handles[i];
718 			status = acpi_bus_get_device(handle, &dev);
719 			if (ACPI_FAILURE(status) || dev != device)
720 				continue;
721 			if (bind)
722 				result =
723 					thermal_zone_bind_cooling_device
724 					(thermal, trip, cdev,
725 					 THERMAL_NO_LIMIT, THERMAL_NO_LIMIT,
726 					 THERMAL_WEIGHT_DEFAULT);
727 			else
728 				result =
729 					thermal_zone_unbind_cooling_device
730 					(thermal, trip, cdev);
731 			if (result)
732 				goto failed;
733 		}
734 	}
735 
736 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
737 		if (!tz->trips.active[i].flags.valid)
738 			break;
739 		trip++;
740 		for (j = 0;
741 		    j < tz->trips.active[i].devices.count;
742 		    j++) {
743 			handle = tz->trips.active[i].devices.handles[j];
744 			status = acpi_bus_get_device(handle, &dev);
745 			if (ACPI_FAILURE(status) || dev != device)
746 				continue;
747 			if (bind)
748 				result = thermal_zone_bind_cooling_device
749 					(thermal, trip, cdev,
750 					 THERMAL_NO_LIMIT, THERMAL_NO_LIMIT,
751 					 THERMAL_WEIGHT_DEFAULT);
752 			else
753 				result = thermal_zone_unbind_cooling_device
754 					(thermal, trip, cdev);
755 			if (result)
756 				goto failed;
757 		}
758 	}
759 
760 failed:
761 	return result;
762 }
763 
764 static int
765 acpi_thermal_bind_cooling_device(struct thermal_zone_device *thermal,
766 					struct thermal_cooling_device *cdev)
767 {
768 	return acpi_thermal_cooling_device_cb(thermal, cdev, true);
769 }
770 
771 static int
772 acpi_thermal_unbind_cooling_device(struct thermal_zone_device *thermal,
773 					struct thermal_cooling_device *cdev)
774 {
775 	return acpi_thermal_cooling_device_cb(thermal, cdev, false);
776 }
777 
778 static struct thermal_zone_device_ops acpi_thermal_zone_ops = {
779 	.bind = acpi_thermal_bind_cooling_device,
780 	.unbind	= acpi_thermal_unbind_cooling_device,
781 	.get_temp = thermal_get_temp,
782 	.get_trip_type = thermal_get_trip_type,
783 	.get_trip_temp = thermal_get_trip_temp,
784 	.get_crit_temp = thermal_get_crit_temp,
785 	.get_trend = thermal_get_trend,
786 	.hot = acpi_thermal_zone_device_hot,
787 	.critical = acpi_thermal_zone_device_critical,
788 };
789 
790 static int acpi_thermal_register_thermal_zone(struct acpi_thermal *tz)
791 {
792 	int trips = 0;
793 	int result;
794 	acpi_status status;
795 	int i;
796 
797 	if (tz->trips.critical.flags.valid)
798 		trips++;
799 
800 	if (tz->trips.hot.flags.valid)
801 		trips++;
802 
803 	if (tz->trips.passive.flags.valid)
804 		trips++;
805 
806 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE &&
807 			tz->trips.active[i].flags.valid; i++, trips++);
808 
809 	if (tz->trips.passive.flags.valid)
810 		tz->thermal_zone =
811 			thermal_zone_device_register("acpitz", trips, 0, tz,
812 						&acpi_thermal_zone_ops, NULL,
813 						     tz->trips.passive.tsp*100,
814 						     tz->polling_frequency*100);
815 	else
816 		tz->thermal_zone =
817 			thermal_zone_device_register("acpitz", trips, 0, tz,
818 						&acpi_thermal_zone_ops, NULL,
819 						0, tz->polling_frequency*100);
820 	if (IS_ERR(tz->thermal_zone))
821 		return -ENODEV;
822 
823 	result = sysfs_create_link(&tz->device->dev.kobj,
824 				   &tz->thermal_zone->device.kobj, "thermal_zone");
825 	if (result)
826 		goto unregister_tzd;
827 
828 	result = sysfs_create_link(&tz->thermal_zone->device.kobj,
829 				   &tz->device->dev.kobj, "device");
830 	if (result)
831 		goto remove_tz_link;
832 
833 	status =  acpi_bus_attach_private_data(tz->device->handle,
834 					       tz->thermal_zone);
835 	if (ACPI_FAILURE(status)) {
836 		result = -ENODEV;
837 		goto remove_dev_link;
838 	}
839 
840 	result = thermal_zone_device_enable(tz->thermal_zone);
841 	if (result)
842 		goto acpi_bus_detach;
843 
844 	dev_info(&tz->device->dev, "registered as thermal_zone%d\n",
845 		 tz->thermal_zone->id);
846 
847 	return 0;
848 
849 acpi_bus_detach:
850 	acpi_bus_detach_private_data(tz->device->handle);
851 remove_dev_link:
852 	sysfs_remove_link(&tz->thermal_zone->device.kobj, "device");
853 remove_tz_link:
854 	sysfs_remove_link(&tz->device->dev.kobj, "thermal_zone");
855 unregister_tzd:
856 	thermal_zone_device_unregister(tz->thermal_zone);
857 
858 	return result;
859 }
860 
861 static void acpi_thermal_unregister_thermal_zone(struct acpi_thermal *tz)
862 {
863 	sysfs_remove_link(&tz->device->dev.kobj, "thermal_zone");
864 	sysfs_remove_link(&tz->thermal_zone->device.kobj, "device");
865 	thermal_zone_device_unregister(tz->thermal_zone);
866 	tz->thermal_zone = NULL;
867 	acpi_bus_detach_private_data(tz->device->handle);
868 }
869 
870 
871 /* --------------------------------------------------------------------------
872                                  Driver Interface
873    -------------------------------------------------------------------------- */
874 
875 static void acpi_queue_thermal_check(struct acpi_thermal *tz)
876 {
877 	if (!work_pending(&tz->thermal_check_work))
878 		queue_work(acpi_thermal_pm_queue, &tz->thermal_check_work);
879 }
880 
881 static void acpi_thermal_notify(struct acpi_device *device, u32 event)
882 {
883 	struct acpi_thermal *tz = acpi_driver_data(device);
884 
885 
886 	if (!tz)
887 		return;
888 
889 	switch (event) {
890 	case ACPI_THERMAL_NOTIFY_TEMPERATURE:
891 		acpi_queue_thermal_check(tz);
892 		break;
893 	case ACPI_THERMAL_NOTIFY_THRESHOLDS:
894 		acpi_thermal_trips_update(tz, ACPI_TRIPS_REFRESH_THRESHOLDS);
895 		acpi_queue_thermal_check(tz);
896 		acpi_bus_generate_netlink_event(device->pnp.device_class,
897 						  dev_name(&device->dev), event, 0);
898 		break;
899 	case ACPI_THERMAL_NOTIFY_DEVICES:
900 		acpi_thermal_trips_update(tz, ACPI_TRIPS_REFRESH_DEVICES);
901 		acpi_queue_thermal_check(tz);
902 		acpi_bus_generate_netlink_event(device->pnp.device_class,
903 						  dev_name(&device->dev), event, 0);
904 		break;
905 	default:
906 		acpi_handle_debug(device->handle, "Unsupported event [0x%x]\n",
907 				  event);
908 		break;
909 	}
910 }
911 
912 /*
913  * On some platforms, the AML code has dependency about
914  * the evaluating order of _TMP and _CRT/_HOT/_PSV/_ACx.
915  * 1. On HP Pavilion G4-1016tx, _TMP must be invoked after
916  *    /_CRT/_HOT/_PSV/_ACx, or else system will be power off.
917  * 2. On HP Compaq 6715b/6715s, the return value of _PSV is 0
918  *    if _TMP has never been evaluated.
919  *
920  * As this dependency is totally transparent to OS, evaluate
921  * all of them once, in the order of _CRT/_HOT/_PSV/_ACx,
922  * _TMP, before they are actually used.
923  */
924 static void acpi_thermal_aml_dependency_fix(struct acpi_thermal *tz)
925 {
926 	acpi_handle handle = tz->device->handle;
927 	unsigned long long value;
928 	int i;
929 
930 	acpi_evaluate_integer(handle, "_CRT", NULL, &value);
931 	acpi_evaluate_integer(handle, "_HOT", NULL, &value);
932 	acpi_evaluate_integer(handle, "_PSV", NULL, &value);
933 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
934 		char name[5] = { '_', 'A', 'C', ('0' + i), '\0' };
935 		acpi_status status;
936 
937 		status = acpi_evaluate_integer(handle, name, NULL, &value);
938 		if (status == AE_NOT_FOUND)
939 			break;
940 	}
941 	acpi_evaluate_integer(handle, "_TMP", NULL, &value);
942 }
943 
944 static int acpi_thermal_get_info(struct acpi_thermal *tz)
945 {
946 	int result = 0;
947 
948 
949 	if (!tz)
950 		return -EINVAL;
951 
952 	acpi_thermal_aml_dependency_fix(tz);
953 
954 	/* Get trip points [_CRT, _PSV, etc.] (required) */
955 	result = acpi_thermal_get_trip_points(tz);
956 	if (result)
957 		return result;
958 
959 	/* Get temperature [_TMP] (required) */
960 	result = acpi_thermal_get_temperature(tz);
961 	if (result)
962 		return result;
963 
964 	/* Set the cooling mode [_SCP] to active cooling (default) */
965 	result = acpi_thermal_set_cooling_mode(tz, ACPI_THERMAL_MODE_ACTIVE);
966 	if (!result)
967 		tz->flags.cooling_mode = 1;
968 
969 	/* Get default polling frequency [_TZP] (optional) */
970 	if (tzp)
971 		tz->polling_frequency = tzp;
972 	else
973 		acpi_thermal_get_polling_frequency(tz);
974 
975 	return 0;
976 }
977 
978 /*
979  * The exact offset between Kelvin and degree Celsius is 273.15. However ACPI
980  * handles temperature values with a single decimal place. As a consequence,
981  * some implementations use an offset of 273.1 and others use an offset of
982  * 273.2. Try to find out which one is being used, to present the most
983  * accurate and visually appealing number.
984  *
985  * The heuristic below should work for all ACPI thermal zones which have a
986  * critical trip point with a value being a multiple of 0.5 degree Celsius.
987  */
988 static void acpi_thermal_guess_offset(struct acpi_thermal *tz)
989 {
990 	if (tz->trips.critical.flags.valid &&
991 	    (tz->trips.critical.temperature % 5) == 1)
992 		tz->kelvin_offset = 273100;
993 	else
994 		tz->kelvin_offset = 273200;
995 }
996 
997 static void acpi_thermal_check_fn(struct work_struct *work)
998 {
999 	struct acpi_thermal *tz = container_of(work, struct acpi_thermal,
1000 					       thermal_check_work);
1001 
1002 	/*
1003 	 * In general, it is not sufficient to check the pending bit, because
1004 	 * subsequent instances of this function may be queued after one of them
1005 	 * has started running (e.g. if _TMP sleeps).  Avoid bailing out if just
1006 	 * one of them is running, though, because it may have done the actual
1007 	 * check some time ago, so allow at least one of them to block on the
1008 	 * mutex while another one is running the update.
1009 	 */
1010 	if (!refcount_dec_not_one(&tz->thermal_check_count))
1011 		return;
1012 
1013 	mutex_lock(&tz->thermal_check_lock);
1014 
1015 	thermal_zone_device_update(tz->thermal_zone, THERMAL_EVENT_UNSPECIFIED);
1016 
1017 	refcount_inc(&tz->thermal_check_count);
1018 
1019 	mutex_unlock(&tz->thermal_check_lock);
1020 }
1021 
1022 static int acpi_thermal_add(struct acpi_device *device)
1023 {
1024 	int result = 0;
1025 	struct acpi_thermal *tz = NULL;
1026 
1027 
1028 	if (!device)
1029 		return -EINVAL;
1030 
1031 	tz = kzalloc(sizeof(struct acpi_thermal), GFP_KERNEL);
1032 	if (!tz)
1033 		return -ENOMEM;
1034 
1035 	tz->device = device;
1036 	strcpy(tz->name, device->pnp.bus_id);
1037 	strcpy(acpi_device_name(device), ACPI_THERMAL_DEVICE_NAME);
1038 	strcpy(acpi_device_class(device), ACPI_THERMAL_CLASS);
1039 	device->driver_data = tz;
1040 
1041 	result = acpi_thermal_get_info(tz);
1042 	if (result)
1043 		goto free_memory;
1044 
1045 	acpi_thermal_guess_offset(tz);
1046 
1047 	result = acpi_thermal_register_thermal_zone(tz);
1048 	if (result)
1049 		goto free_memory;
1050 
1051 	refcount_set(&tz->thermal_check_count, 3);
1052 	mutex_init(&tz->thermal_check_lock);
1053 	INIT_WORK(&tz->thermal_check_work, acpi_thermal_check_fn);
1054 
1055 	pr_info("%s [%s] (%ld C)\n", acpi_device_name(device),
1056 		acpi_device_bid(device), deci_kelvin_to_celsius(tz->temperature));
1057 	goto end;
1058 
1059 free_memory:
1060 	kfree(tz);
1061 end:
1062 	return result;
1063 }
1064 
1065 static int acpi_thermal_remove(struct acpi_device *device)
1066 {
1067 	struct acpi_thermal *tz = NULL;
1068 
1069 	if (!device || !acpi_driver_data(device))
1070 		return -EINVAL;
1071 
1072 	flush_workqueue(acpi_thermal_pm_queue);
1073 	tz = acpi_driver_data(device);
1074 
1075 	acpi_thermal_unregister_thermal_zone(tz);
1076 	kfree(tz);
1077 	return 0;
1078 }
1079 
1080 #ifdef CONFIG_PM_SLEEP
1081 static int acpi_thermal_suspend(struct device *dev)
1082 {
1083 	/* Make sure the previously queued thermal check work has been done */
1084 	flush_workqueue(acpi_thermal_pm_queue);
1085 	return 0;
1086 }
1087 
1088 static int acpi_thermal_resume(struct device *dev)
1089 {
1090 	struct acpi_thermal *tz;
1091 	int i, j, power_state, result;
1092 
1093 	if (!dev)
1094 		return -EINVAL;
1095 
1096 	tz = acpi_driver_data(to_acpi_device(dev));
1097 	if (!tz)
1098 		return -EINVAL;
1099 
1100 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
1101 		if (!(&tz->trips.active[i]))
1102 			break;
1103 		if (!tz->trips.active[i].flags.valid)
1104 			break;
1105 		tz->trips.active[i].flags.enabled = 1;
1106 		for (j = 0; j < tz->trips.active[i].devices.count; j++) {
1107 			result = acpi_bus_update_power(
1108 					tz->trips.active[i].devices.handles[j],
1109 					&power_state);
1110 			if (result || (power_state != ACPI_STATE_D0)) {
1111 				tz->trips.active[i].flags.enabled = 0;
1112 				break;
1113 			}
1114 		}
1115 		tz->state.active |= tz->trips.active[i].flags.enabled;
1116 	}
1117 
1118 	acpi_queue_thermal_check(tz);
1119 
1120 	return AE_OK;
1121 }
1122 #endif
1123 
1124 static int thermal_act(const struct dmi_system_id *d) {
1125 
1126 	if (act == 0) {
1127 		pr_notice("%s detected: disabling all active thermal trip points\n",
1128 			  d->ident);
1129 		act = -1;
1130 	}
1131 	return 0;
1132 }
1133 static int thermal_nocrt(const struct dmi_system_id *d) {
1134 
1135 	pr_notice("%s detected: disabling all critical thermal trip point actions.\n",
1136 		  d->ident);
1137 	nocrt = 1;
1138 	return 0;
1139 }
1140 static int thermal_tzp(const struct dmi_system_id *d) {
1141 
1142 	if (tzp == 0) {
1143 		pr_notice("%s detected: enabling thermal zone polling\n",
1144 			  d->ident);
1145 		tzp = 300;	/* 300 dS = 30 Seconds */
1146 	}
1147 	return 0;
1148 }
1149 static int thermal_psv(const struct dmi_system_id *d) {
1150 
1151 	if (psv == 0) {
1152 		pr_notice("%s detected: disabling all passive thermal trip points\n",
1153 			  d->ident);
1154 		psv = -1;
1155 	}
1156 	return 0;
1157 }
1158 
1159 static const struct dmi_system_id thermal_dmi_table[] __initconst = {
1160 	/*
1161 	 * Award BIOS on this AOpen makes thermal control almost worthless.
1162 	 * http://bugzilla.kernel.org/show_bug.cgi?id=8842
1163 	 */
1164 	{
1165 	 .callback = thermal_act,
1166 	 .ident = "AOpen i915GMm-HFS",
1167 	 .matches = {
1168 		DMI_MATCH(DMI_BOARD_VENDOR, "AOpen"),
1169 		DMI_MATCH(DMI_BOARD_NAME, "i915GMm-HFS"),
1170 		},
1171 	},
1172 	{
1173 	 .callback = thermal_psv,
1174 	 .ident = "AOpen i915GMm-HFS",
1175 	 .matches = {
1176 		DMI_MATCH(DMI_BOARD_VENDOR, "AOpen"),
1177 		DMI_MATCH(DMI_BOARD_NAME, "i915GMm-HFS"),
1178 		},
1179 	},
1180 	{
1181 	 .callback = thermal_tzp,
1182 	 .ident = "AOpen i915GMm-HFS",
1183 	 .matches = {
1184 		DMI_MATCH(DMI_BOARD_VENDOR, "AOpen"),
1185 		DMI_MATCH(DMI_BOARD_NAME, "i915GMm-HFS"),
1186 		},
1187 	},
1188 	{
1189 	 .callback = thermal_nocrt,
1190 	 .ident = "Gigabyte GA-7ZX",
1191 	 .matches = {
1192 		DMI_MATCH(DMI_BOARD_VENDOR, "Gigabyte Technology Co., Ltd."),
1193 		DMI_MATCH(DMI_BOARD_NAME, "7ZX"),
1194 		},
1195 	},
1196 	{}
1197 };
1198 
1199 static int __init acpi_thermal_init(void)
1200 {
1201 	int result = 0;
1202 
1203 	dmi_check_system(thermal_dmi_table);
1204 
1205 	if (off) {
1206 		pr_notice("thermal control disabled\n");
1207 		return -ENODEV;
1208 	}
1209 
1210 	acpi_thermal_pm_queue = alloc_workqueue("acpi_thermal_pm",
1211 						WQ_HIGHPRI | WQ_MEM_RECLAIM, 0);
1212 	if (!acpi_thermal_pm_queue)
1213 		return -ENODEV;
1214 
1215 	result = acpi_bus_register_driver(&acpi_thermal_driver);
1216 	if (result < 0) {
1217 		destroy_workqueue(acpi_thermal_pm_queue);
1218 		return -ENODEV;
1219 	}
1220 
1221 	return 0;
1222 }
1223 
1224 static void __exit acpi_thermal_exit(void)
1225 {
1226 	acpi_bus_unregister_driver(&acpi_thermal_driver);
1227 	destroy_workqueue(acpi_thermal_pm_queue);
1228 
1229 	return;
1230 }
1231 
1232 module_init(acpi_thermal_init);
1233 module_exit(acpi_thermal_exit);
1234