xref: /openbmc/linux/drivers/acpi/thermal.c (revision 2127c01b)
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 #include <linux/kernel.h>
17 #include <linux/module.h>
18 #include <linux/dmi.h>
19 #include <linux/init.h>
20 #include <linux/slab.h>
21 #include <linux/types.h>
22 #include <linux/jiffies.h>
23 #include <linux/kmod.h>
24 #include <linux/reboot.h>
25 #include <linux/device.h>
26 #include <linux/thermal.h>
27 #include <linux/acpi.h>
28 #include <linux/workqueue.h>
29 #include <linux/uaccess.h>
30 
31 #define PREFIX "ACPI: "
32 
33 #define ACPI_THERMAL_CLASS		"thermal_zone"
34 #define ACPI_THERMAL_DEVICE_NAME	"Thermal Zone"
35 #define ACPI_THERMAL_NOTIFY_TEMPERATURE	0x80
36 #define ACPI_THERMAL_NOTIFY_THRESHOLDS	0x81
37 #define ACPI_THERMAL_NOTIFY_DEVICES	0x82
38 #define ACPI_THERMAL_NOTIFY_CRITICAL	0xF0
39 #define ACPI_THERMAL_NOTIFY_HOT		0xF1
40 #define ACPI_THERMAL_MODE_ACTIVE	0x00
41 
42 #define ACPI_THERMAL_MAX_ACTIVE	10
43 #define ACPI_THERMAL_MAX_LIMIT_STR_LEN 65
44 
45 #define _COMPONENT		ACPI_THERMAL_COMPONENT
46 ACPI_MODULE_NAME("thermal");
47 
48 MODULE_AUTHOR("Paul Diefenbaugh");
49 MODULE_DESCRIPTION("ACPI Thermal Zone Driver");
50 MODULE_LICENSE("GPL");
51 
52 static int act;
53 module_param(act, int, 0644);
54 MODULE_PARM_DESC(act, "Disable or override all lowest active trip points.");
55 
56 static int crt;
57 module_param(crt, int, 0644);
58 MODULE_PARM_DESC(crt, "Disable or lower all critical trip points.");
59 
60 static int tzp;
61 module_param(tzp, int, 0444);
62 MODULE_PARM_DESC(tzp, "Thermal zone polling frequency, in 1/10 seconds.");
63 
64 static int nocrt;
65 module_param(nocrt, int, 0);
66 MODULE_PARM_DESC(nocrt, "Set to take no action upon ACPI thermal zone critical trips points.");
67 
68 static int off;
69 module_param(off, int, 0);
70 MODULE_PARM_DESC(off, "Set to disable ACPI thermal support.");
71 
72 static int psv;
73 module_param(psv, int, 0644);
74 MODULE_PARM_DESC(psv, "Disable or override all passive trip points.");
75 
76 static struct workqueue_struct *acpi_thermal_pm_queue;
77 
78 static int acpi_thermal_add(struct acpi_device *device);
79 static int acpi_thermal_remove(struct acpi_device *device);
80 static void acpi_thermal_notify(struct acpi_device *device, u32 event);
81 
82 static const struct acpi_device_id  thermal_device_ids[] = {
83 	{ACPI_THERMAL_HID, 0},
84 	{"", 0},
85 };
86 MODULE_DEVICE_TABLE(acpi, thermal_device_ids);
87 
88 #ifdef CONFIG_PM_SLEEP
89 static int acpi_thermal_suspend(struct device *dev);
90 static int acpi_thermal_resume(struct device *dev);
91 #else
92 #define acpi_thermal_suspend NULL
93 #define acpi_thermal_resume NULL
94 #endif
95 static SIMPLE_DEV_PM_OPS(acpi_thermal_pm, acpi_thermal_suspend, acpi_thermal_resume);
96 
97 static struct acpi_driver acpi_thermal_driver = {
98 	.name = "thermal",
99 	.class = ACPI_THERMAL_CLASS,
100 	.ids = thermal_device_ids,
101 	.ops = {
102 		.add = acpi_thermal_add,
103 		.remove = acpi_thermal_remove,
104 		.notify = acpi_thermal_notify,
105 		},
106 	.drv.pm = &acpi_thermal_pm,
107 };
108 
109 struct acpi_thermal_state {
110 	u8 critical:1;
111 	u8 hot:1;
112 	u8 passive:1;
113 	u8 active:1;
114 	u8 reserved:4;
115 	int active_index;
116 };
117 
118 struct acpi_thermal_state_flags {
119 	u8 valid:1;
120 	u8 enabled:1;
121 	u8 reserved:6;
122 };
123 
124 struct acpi_thermal_critical {
125 	struct acpi_thermal_state_flags flags;
126 	unsigned long temperature;
127 };
128 
129 struct acpi_thermal_hot {
130 	struct acpi_thermal_state_flags flags;
131 	unsigned long temperature;
132 };
133 
134 struct acpi_thermal_passive {
135 	struct acpi_thermal_state_flags flags;
136 	unsigned long temperature;
137 	unsigned long tc1;
138 	unsigned long tc2;
139 	unsigned long tsp;
140 	struct acpi_handle_list devices;
141 };
142 
143 struct acpi_thermal_active {
144 	struct acpi_thermal_state_flags flags;
145 	unsigned long temperature;
146 	struct acpi_handle_list devices;
147 };
148 
149 struct acpi_thermal_trips {
150 	struct acpi_thermal_critical critical;
151 	struct acpi_thermal_hot hot;
152 	struct acpi_thermal_passive passive;
153 	struct acpi_thermal_active active[ACPI_THERMAL_MAX_ACTIVE];
154 };
155 
156 struct acpi_thermal_flags {
157 	u8 cooling_mode:1;	/* _SCP */
158 	u8 devices:1;		/* _TZD */
159 	u8 reserved:6;
160 };
161 
162 struct acpi_thermal {
163 	struct acpi_device * device;
164 	acpi_bus_id name;
165 	unsigned long temperature;
166 	unsigned long last_temperature;
167 	unsigned long polling_frequency;
168 	volatile u8 zombie;
169 	struct acpi_thermal_flags flags;
170 	struct acpi_thermal_state state;
171 	struct acpi_thermal_trips trips;
172 	struct acpi_handle_list devices;
173 	struct thermal_zone_device *thermal_zone;
174 	int tz_enabled;
175 	int kelvin_offset;
176 	struct work_struct thermal_check_work;
177 };
178 
179 /* --------------------------------------------------------------------------
180                              Thermal Zone Management
181    -------------------------------------------------------------------------- */
182 
183 static int acpi_thermal_get_temperature(struct acpi_thermal *tz)
184 {
185 	acpi_status status = AE_OK;
186 	unsigned long long tmp;
187 
188 	if (!tz)
189 		return -EINVAL;
190 
191 	tz->last_temperature = tz->temperature;
192 
193 	status = acpi_evaluate_integer(tz->device->handle, "_TMP", NULL, &tmp);
194 	if (ACPI_FAILURE(status))
195 		return -ENODEV;
196 
197 	tz->temperature = tmp;
198 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "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_DEBUG_PRINT((ACPI_DB_INFO, "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_has_method(tz->device->handle, "_SCP")) {
229 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "_SCP not present\n"));
230 		return -ENODEV;
231 	} else if (ACPI_FAILURE(acpi_execute_simple_method(tz->device->handle,
232 							   "_SCP", mode))) {
233 		return -ENODEV;
234 	}
235 
236 	return 0;
237 }
238 
239 #define ACPI_TRIPS_CRITICAL	0x01
240 #define ACPI_TRIPS_HOT		0x02
241 #define ACPI_TRIPS_PASSIVE	0x04
242 #define ACPI_TRIPS_ACTIVE	0x08
243 #define ACPI_TRIPS_DEVICES	0x10
244 
245 #define ACPI_TRIPS_REFRESH_THRESHOLDS	(ACPI_TRIPS_PASSIVE | ACPI_TRIPS_ACTIVE)
246 #define ACPI_TRIPS_REFRESH_DEVICES	ACPI_TRIPS_DEVICES
247 
248 #define ACPI_TRIPS_INIT      (ACPI_TRIPS_CRITICAL | ACPI_TRIPS_HOT |	\
249 			      ACPI_TRIPS_PASSIVE | ACPI_TRIPS_ACTIVE |	\
250 			      ACPI_TRIPS_DEVICES)
251 
252 /*
253  * This exception is thrown out in two cases:
254  * 1.An invalid trip point becomes invalid or a valid trip point becomes invalid
255  *   when re-evaluating the AML code.
256  * 2.TODO: Devices listed in _PSL, _ALx, _TZD may change.
257  *   We need to re-bind the cooling devices of a thermal zone when this occurs.
258  */
259 #define ACPI_THERMAL_TRIPS_EXCEPTION(flags, str)	\
260 do {	\
261 	if (flags != ACPI_TRIPS_INIT)	\
262 		ACPI_EXCEPTION((AE_INFO, AE_ERROR,	\
263 		"ACPI thermal trip point %s changed\n"	\
264 		"Please send acpidump to linux-acpi@vger.kernel.org", str)); \
265 } while (0)
266 
267 static int acpi_thermal_trips_update(struct acpi_thermal *tz, int flag)
268 {
269 	acpi_status status = AE_OK;
270 	unsigned long long tmp;
271 	struct acpi_handle_list devices;
272 	int valid = 0;
273 	int i;
274 
275 	/* Critical Shutdown */
276 	if (flag & ACPI_TRIPS_CRITICAL) {
277 		status = acpi_evaluate_integer(tz->device->handle,
278 				"_CRT", NULL, &tmp);
279 		tz->trips.critical.temperature = tmp;
280 		/*
281 		 * Treat freezing temperatures as invalid as well; some
282 		 * BIOSes return really low values and cause reboots at startup.
283 		 * Below zero (Celsius) values clearly aren't right for sure..
284 		 * ... so lets discard those as invalid.
285 		 */
286 		if (ACPI_FAILURE(status)) {
287 			tz->trips.critical.flags.valid = 0;
288 			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
289 					  "No critical threshold\n"));
290 		} else if (tmp <= 2732) {
291 			pr_warn(FW_BUG "Invalid critical threshold (%llu)\n",
292 				tmp);
293 			tz->trips.critical.flags.valid = 0;
294 		} else {
295 			tz->trips.critical.flags.valid = 1;
296 			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
297 					  "Found critical threshold [%lu]\n",
298 					  tz->trips.critical.temperature));
299 		}
300 		if (tz->trips.critical.flags.valid == 1) {
301 			if (crt == -1) {
302 				tz->trips.critical.flags.valid = 0;
303 			} else if (crt > 0) {
304 				unsigned long crt_k = CELSIUS_TO_DECI_KELVIN(crt);
305 				/*
306 				 * Allow override critical threshold
307 				 */
308 				if (crt_k > tz->trips.critical.temperature)
309 					pr_warn(PREFIX "Critical threshold %d C\n",
310 						crt);
311 				tz->trips.critical.temperature = crt_k;
312 			}
313 		}
314 	}
315 
316 	/* Critical Sleep (optional) */
317 	if (flag & ACPI_TRIPS_HOT) {
318 		status = acpi_evaluate_integer(tz->device->handle,
319 				"_HOT", NULL, &tmp);
320 		if (ACPI_FAILURE(status)) {
321 			tz->trips.hot.flags.valid = 0;
322 			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
323 					"No hot threshold\n"));
324 		} else {
325 			tz->trips.hot.temperature = tmp;
326 			tz->trips.hot.flags.valid = 1;
327 			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
328 					"Found hot threshold [%lu]\n",
329 					tz->trips.hot.temperature));
330 		}
331 	}
332 
333 	/* Passive (optional) */
334 	if (((flag & ACPI_TRIPS_PASSIVE) && tz->trips.passive.flags.valid) ||
335 		(flag == ACPI_TRIPS_INIT)) {
336 		valid = tz->trips.passive.flags.valid;
337 		if (psv == -1) {
338 			status = AE_SUPPORT;
339 		} else if (psv > 0) {
340 			tmp = CELSIUS_TO_DECI_KELVIN(psv);
341 			status = AE_OK;
342 		} else {
343 			status = acpi_evaluate_integer(tz->device->handle,
344 				"_PSV", NULL, &tmp);
345 		}
346 
347 		if (ACPI_FAILURE(status))
348 			tz->trips.passive.flags.valid = 0;
349 		else {
350 			tz->trips.passive.temperature = tmp;
351 			tz->trips.passive.flags.valid = 1;
352 			if (flag == ACPI_TRIPS_INIT) {
353 				status = acpi_evaluate_integer(
354 						tz->device->handle, "_TC1",
355 						NULL, &tmp);
356 				if (ACPI_FAILURE(status))
357 					tz->trips.passive.flags.valid = 0;
358 				else
359 					tz->trips.passive.tc1 = tmp;
360 				status = acpi_evaluate_integer(
361 						tz->device->handle, "_TC2",
362 						NULL, &tmp);
363 				if (ACPI_FAILURE(status))
364 					tz->trips.passive.flags.valid = 0;
365 				else
366 					tz->trips.passive.tc2 = tmp;
367 				status = acpi_evaluate_integer(
368 						tz->device->handle, "_TSP",
369 						NULL, &tmp);
370 				if (ACPI_FAILURE(status))
371 					tz->trips.passive.flags.valid = 0;
372 				else
373 					tz->trips.passive.tsp = tmp;
374 			}
375 		}
376 	}
377 	if ((flag & ACPI_TRIPS_DEVICES) && tz->trips.passive.flags.valid) {
378 		memset(&devices, 0, sizeof(struct acpi_handle_list));
379 		status = acpi_evaluate_reference(tz->device->handle, "_PSL",
380 							NULL, &devices);
381 		if (ACPI_FAILURE(status)) {
382 			pr_warn(PREFIX "Invalid passive threshold\n");
383 			tz->trips.passive.flags.valid = 0;
384 		}
385 		else
386 			tz->trips.passive.flags.valid = 1;
387 
388 		if (memcmp(&tz->trips.passive.devices, &devices,
389 				sizeof(struct acpi_handle_list))) {
390 			memcpy(&tz->trips.passive.devices, &devices,
391 				sizeof(struct acpi_handle_list));
392 			ACPI_THERMAL_TRIPS_EXCEPTION(flag, "device");
393 		}
394 	}
395 	if ((flag & ACPI_TRIPS_PASSIVE) || (flag & ACPI_TRIPS_DEVICES)) {
396 		if (valid != tz->trips.passive.flags.valid)
397 				ACPI_THERMAL_TRIPS_EXCEPTION(flag, "state");
398 	}
399 
400 	/* Active (optional) */
401 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
402 		char name[5] = { '_', 'A', 'C', ('0' + i), '\0' };
403 		valid = tz->trips.active[i].flags.valid;
404 
405 		if (act == -1)
406 			break; /* disable all active trip points */
407 
408 		if ((flag == ACPI_TRIPS_INIT) || ((flag & ACPI_TRIPS_ACTIVE) &&
409 			tz->trips.active[i].flags.valid)) {
410 			status = acpi_evaluate_integer(tz->device->handle,
411 							name, NULL, &tmp);
412 			if (ACPI_FAILURE(status)) {
413 				tz->trips.active[i].flags.valid = 0;
414 				if (i == 0)
415 					break;
416 				if (act <= 0)
417 					break;
418 				if (i == 1)
419 					tz->trips.active[0].temperature =
420 						CELSIUS_TO_DECI_KELVIN(act);
421 				else
422 					/*
423 					 * Don't allow override higher than
424 					 * the next higher trip point
425 					 */
426 					tz->trips.active[i - 1].temperature =
427 						(tz->trips.active[i - 2].temperature <
428 						CELSIUS_TO_DECI_KELVIN(act) ?
429 						tz->trips.active[i - 2].temperature :
430 						CELSIUS_TO_DECI_KELVIN(act));
431 				break;
432 			} else {
433 				tz->trips.active[i].temperature = tmp;
434 				tz->trips.active[i].flags.valid = 1;
435 			}
436 		}
437 
438 		name[2] = 'L';
439 		if ((flag & ACPI_TRIPS_DEVICES) && tz->trips.active[i].flags.valid ) {
440 			memset(&devices, 0, sizeof(struct acpi_handle_list));
441 			status = acpi_evaluate_reference(tz->device->handle,
442 						name, NULL, &devices);
443 			if (ACPI_FAILURE(status)) {
444 				pr_warn(PREFIX "Invalid active%d threshold\n",
445 					i);
446 				tz->trips.active[i].flags.valid = 0;
447 			}
448 			else
449 				tz->trips.active[i].flags.valid = 1;
450 
451 			if (memcmp(&tz->trips.active[i].devices, &devices,
452 					sizeof(struct acpi_handle_list))) {
453 				memcpy(&tz->trips.active[i].devices, &devices,
454 					sizeof(struct acpi_handle_list));
455 				ACPI_THERMAL_TRIPS_EXCEPTION(flag, "device");
456 			}
457 		}
458 		if ((flag & ACPI_TRIPS_ACTIVE) || (flag & ACPI_TRIPS_DEVICES))
459 			if (valid != tz->trips.active[i].flags.valid)
460 				ACPI_THERMAL_TRIPS_EXCEPTION(flag, "state");
461 
462 		if (!tz->trips.active[i].flags.valid)
463 			break;
464 	}
465 
466 	if ((flag & ACPI_TRIPS_DEVICES)
467 	    && acpi_has_method(tz->device->handle, "_TZD")) {
468 		memset(&devices, 0, sizeof(devices));
469 		status = acpi_evaluate_reference(tz->device->handle, "_TZD",
470 						NULL, &devices);
471 		if (ACPI_SUCCESS(status)
472 		    && memcmp(&tz->devices, &devices, sizeof(devices))) {
473 			tz->devices = devices;
474 			ACPI_THERMAL_TRIPS_EXCEPTION(flag, "device");
475 		}
476 	}
477 
478 	return 0;
479 }
480 
481 static int acpi_thermal_get_trip_points(struct acpi_thermal *tz)
482 {
483 	int i, valid, ret = acpi_thermal_trips_update(tz, ACPI_TRIPS_INIT);
484 
485 	if (ret)
486 		return ret;
487 
488 	valid = tz->trips.critical.flags.valid |
489 		tz->trips.hot.flags.valid |
490 		tz->trips.passive.flags.valid;
491 
492 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++)
493 		valid |= tz->trips.active[i].flags.valid;
494 
495 	if (!valid) {
496 		pr_warn(FW_BUG "No valid trip found\n");
497 		return -ENODEV;
498 	}
499 	return 0;
500 }
501 
502 static void acpi_thermal_check(void *data)
503 {
504 	struct acpi_thermal *tz = data;
505 
506 	if (!tz->tz_enabled)
507 		return;
508 
509 	thermal_zone_device_update(tz->thermal_zone,
510 				   THERMAL_EVENT_UNSPECIFIED);
511 }
512 
513 /* sys I/F for generic thermal sysfs support */
514 
515 static int thermal_get_temp(struct thermal_zone_device *thermal, int *temp)
516 {
517 	struct acpi_thermal *tz = thermal->devdata;
518 	int result;
519 
520 	if (!tz)
521 		return -EINVAL;
522 
523 	result = acpi_thermal_get_temperature(tz);
524 	if (result)
525 		return result;
526 
527 	*temp = DECI_KELVIN_TO_MILLICELSIUS_WITH_OFFSET(tz->temperature,
528 							tz->kelvin_offset);
529 	return 0;
530 }
531 
532 static int thermal_get_mode(struct thermal_zone_device *thermal,
533 				enum thermal_device_mode *mode)
534 {
535 	struct acpi_thermal *tz = thermal->devdata;
536 
537 	if (!tz)
538 		return -EINVAL;
539 
540 	*mode = tz->tz_enabled ? THERMAL_DEVICE_ENABLED :
541 		THERMAL_DEVICE_DISABLED;
542 
543 	return 0;
544 }
545 
546 static int thermal_set_mode(struct thermal_zone_device *thermal,
547 				enum thermal_device_mode mode)
548 {
549 	struct acpi_thermal *tz = thermal->devdata;
550 	int enable;
551 
552 	if (!tz)
553 		return -EINVAL;
554 
555 	/*
556 	 * enable/disable thermal management from ACPI thermal driver
557 	 */
558 	if (mode == THERMAL_DEVICE_ENABLED)
559 		enable = 1;
560 	else if (mode == THERMAL_DEVICE_DISABLED) {
561 		enable = 0;
562 		pr_warn("thermal zone will be disabled\n");
563 	} else
564 		return -EINVAL;
565 
566 	if (enable != tz->tz_enabled) {
567 		tz->tz_enabled = enable;
568 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
569 			"%s kernel ACPI thermal control\n",
570 			tz->tz_enabled ? "Enable" : "Disable"));
571 		acpi_thermal_check(tz);
572 	}
573 	return 0;
574 }
575 
576 static int thermal_get_trip_type(struct thermal_zone_device *thermal,
577 				 int trip, enum thermal_trip_type *type)
578 {
579 	struct acpi_thermal *tz = thermal->devdata;
580 	int i;
581 
582 	if (!tz || trip < 0)
583 		return -EINVAL;
584 
585 	if (tz->trips.critical.flags.valid) {
586 		if (!trip) {
587 			*type = THERMAL_TRIP_CRITICAL;
588 			return 0;
589 		}
590 		trip--;
591 	}
592 
593 	if (tz->trips.hot.flags.valid) {
594 		if (!trip) {
595 			*type = THERMAL_TRIP_HOT;
596 			return 0;
597 		}
598 		trip--;
599 	}
600 
601 	if (tz->trips.passive.flags.valid) {
602 		if (!trip) {
603 			*type = THERMAL_TRIP_PASSIVE;
604 			return 0;
605 		}
606 		trip--;
607 	}
608 
609 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE &&
610 		tz->trips.active[i].flags.valid; i++) {
611 		if (!trip) {
612 			*type = THERMAL_TRIP_ACTIVE;
613 			return 0;
614 		}
615 		trip--;
616 	}
617 
618 	return -EINVAL;
619 }
620 
621 static int thermal_get_trip_temp(struct thermal_zone_device *thermal,
622 				 int trip, int *temp)
623 {
624 	struct acpi_thermal *tz = thermal->devdata;
625 	int i;
626 
627 	if (!tz || trip < 0)
628 		return -EINVAL;
629 
630 	if (tz->trips.critical.flags.valid) {
631 		if (!trip) {
632 			*temp = DECI_KELVIN_TO_MILLICELSIUS_WITH_OFFSET(
633 				tz->trips.critical.temperature,
634 				tz->kelvin_offset);
635 			return 0;
636 		}
637 		trip--;
638 	}
639 
640 	if (tz->trips.hot.flags.valid) {
641 		if (!trip) {
642 			*temp = DECI_KELVIN_TO_MILLICELSIUS_WITH_OFFSET(
643 				tz->trips.hot.temperature,
644 				tz->kelvin_offset);
645 			return 0;
646 		}
647 		trip--;
648 	}
649 
650 	if (tz->trips.passive.flags.valid) {
651 		if (!trip) {
652 			*temp = DECI_KELVIN_TO_MILLICELSIUS_WITH_OFFSET(
653 				tz->trips.passive.temperature,
654 				tz->kelvin_offset);
655 			return 0;
656 		}
657 		trip--;
658 	}
659 
660 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE &&
661 		tz->trips.active[i].flags.valid; i++) {
662 		if (!trip) {
663 			*temp = DECI_KELVIN_TO_MILLICELSIUS_WITH_OFFSET(
664 				tz->trips.active[i].temperature,
665 				tz->kelvin_offset);
666 			return 0;
667 		}
668 		trip--;
669 	}
670 
671 	return -EINVAL;
672 }
673 
674 static int thermal_get_crit_temp(struct thermal_zone_device *thermal,
675 				int *temperature)
676 {
677 	struct acpi_thermal *tz = thermal->devdata;
678 
679 	if (tz->trips.critical.flags.valid) {
680 		*temperature = DECI_KELVIN_TO_MILLICELSIUS_WITH_OFFSET(
681 				tz->trips.critical.temperature,
682 				tz->kelvin_offset);
683 		return 0;
684 	} else
685 		return -EINVAL;
686 }
687 
688 static int thermal_get_trend(struct thermal_zone_device *thermal,
689 				int trip, enum thermal_trend *trend)
690 {
691 	struct acpi_thermal *tz = thermal->devdata;
692 	enum thermal_trip_type type;
693 	int i;
694 
695 	if (thermal_get_trip_type(thermal, trip, &type))
696 		return -EINVAL;
697 
698 	if (type == THERMAL_TRIP_ACTIVE) {
699 		int trip_temp;
700 		int temp = DECI_KELVIN_TO_MILLICELSIUS_WITH_OFFSET(
701 					tz->temperature, tz->kelvin_offset);
702 		if (thermal_get_trip_temp(thermal, trip, &trip_temp))
703 			return -EINVAL;
704 
705 		if (temp > trip_temp) {
706 			*trend = THERMAL_TREND_RAISING;
707 			return 0;
708 		} else {
709 			/* Fall back on default trend */
710 			return -EINVAL;
711 		}
712 	}
713 
714 	/*
715 	 * tz->temperature has already been updated by generic thermal layer,
716 	 * before this callback being invoked
717 	 */
718 	i = (tz->trips.passive.tc1 * (tz->temperature - tz->last_temperature))
719 		+ (tz->trips.passive.tc2
720 		* (tz->temperature - tz->trips.passive.temperature));
721 
722 	if (i > 0)
723 		*trend = THERMAL_TREND_RAISING;
724 	else if (i < 0)
725 		*trend = THERMAL_TREND_DROPPING;
726 	else
727 		*trend = THERMAL_TREND_STABLE;
728 	return 0;
729 }
730 
731 
732 static int thermal_notify(struct thermal_zone_device *thermal, int trip,
733 			   enum thermal_trip_type trip_type)
734 {
735 	u8 type = 0;
736 	struct acpi_thermal *tz = thermal->devdata;
737 
738 	if (trip_type == THERMAL_TRIP_CRITICAL)
739 		type = ACPI_THERMAL_NOTIFY_CRITICAL;
740 	else if (trip_type == THERMAL_TRIP_HOT)
741 		type = ACPI_THERMAL_NOTIFY_HOT;
742 	else
743 		return 0;
744 
745 	acpi_bus_generate_netlink_event(tz->device->pnp.device_class,
746 					dev_name(&tz->device->dev), type, 1);
747 
748 	if (trip_type == THERMAL_TRIP_CRITICAL && nocrt)
749 		return 1;
750 
751 	return 0;
752 }
753 
754 static int acpi_thermal_cooling_device_cb(struct thermal_zone_device *thermal,
755 					struct thermal_cooling_device *cdev,
756 					bool bind)
757 {
758 	struct acpi_device *device = cdev->devdata;
759 	struct acpi_thermal *tz = thermal->devdata;
760 	struct acpi_device *dev;
761 	acpi_status status;
762 	acpi_handle handle;
763 	int i;
764 	int j;
765 	int trip = -1;
766 	int result = 0;
767 
768 	if (tz->trips.critical.flags.valid)
769 		trip++;
770 
771 	if (tz->trips.hot.flags.valid)
772 		trip++;
773 
774 	if (tz->trips.passive.flags.valid) {
775 		trip++;
776 		for (i = 0; i < tz->trips.passive.devices.count;
777 		    i++) {
778 			handle = tz->trips.passive.devices.handles[i];
779 			status = acpi_bus_get_device(handle, &dev);
780 			if (ACPI_FAILURE(status) || dev != device)
781 				continue;
782 			if (bind)
783 				result =
784 					thermal_zone_bind_cooling_device
785 					(thermal, trip, cdev,
786 					 THERMAL_NO_LIMIT, THERMAL_NO_LIMIT,
787 					 THERMAL_WEIGHT_DEFAULT);
788 			else
789 				result =
790 					thermal_zone_unbind_cooling_device
791 					(thermal, trip, cdev);
792 			if (result)
793 				goto failed;
794 		}
795 	}
796 
797 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
798 		if (!tz->trips.active[i].flags.valid)
799 			break;
800 		trip++;
801 		for (j = 0;
802 		    j < tz->trips.active[i].devices.count;
803 		    j++) {
804 			handle = tz->trips.active[i].devices.handles[j];
805 			status = acpi_bus_get_device(handle, &dev);
806 			if (ACPI_FAILURE(status) || dev != device)
807 				continue;
808 			if (bind)
809 				result = thermal_zone_bind_cooling_device
810 					(thermal, trip, cdev,
811 					 THERMAL_NO_LIMIT, THERMAL_NO_LIMIT,
812 					 THERMAL_WEIGHT_DEFAULT);
813 			else
814 				result = thermal_zone_unbind_cooling_device
815 					(thermal, trip, cdev);
816 			if (result)
817 				goto failed;
818 		}
819 	}
820 
821 	for (i = 0; i < tz->devices.count; i++) {
822 		handle = tz->devices.handles[i];
823 		status = acpi_bus_get_device(handle, &dev);
824 		if (ACPI_SUCCESS(status) && (dev == device)) {
825 			if (bind)
826 				result = thermal_zone_bind_cooling_device
827 						(thermal, THERMAL_TRIPS_NONE,
828 						 cdev, THERMAL_NO_LIMIT,
829 						 THERMAL_NO_LIMIT,
830 						 THERMAL_WEIGHT_DEFAULT);
831 			else
832 				result = thermal_zone_unbind_cooling_device
833 						(thermal, THERMAL_TRIPS_NONE,
834 						 cdev);
835 			if (result)
836 				goto failed;
837 		}
838 	}
839 
840 failed:
841 	return result;
842 }
843 
844 static int
845 acpi_thermal_bind_cooling_device(struct thermal_zone_device *thermal,
846 					struct thermal_cooling_device *cdev)
847 {
848 	return acpi_thermal_cooling_device_cb(thermal, cdev, true);
849 }
850 
851 static int
852 acpi_thermal_unbind_cooling_device(struct thermal_zone_device *thermal,
853 					struct thermal_cooling_device *cdev)
854 {
855 	return acpi_thermal_cooling_device_cb(thermal, cdev, false);
856 }
857 
858 static struct thermal_zone_device_ops acpi_thermal_zone_ops = {
859 	.bind = acpi_thermal_bind_cooling_device,
860 	.unbind	= acpi_thermal_unbind_cooling_device,
861 	.get_temp = thermal_get_temp,
862 	.get_mode = thermal_get_mode,
863 	.set_mode = thermal_set_mode,
864 	.get_trip_type = thermal_get_trip_type,
865 	.get_trip_temp = thermal_get_trip_temp,
866 	.get_crit_temp = thermal_get_crit_temp,
867 	.get_trend = thermal_get_trend,
868 	.notify = thermal_notify,
869 };
870 
871 static int acpi_thermal_register_thermal_zone(struct acpi_thermal *tz)
872 {
873 	int trips = 0;
874 	int result;
875 	acpi_status status;
876 	int i;
877 
878 	if (tz->trips.critical.flags.valid)
879 		trips++;
880 
881 	if (tz->trips.hot.flags.valid)
882 		trips++;
883 
884 	if (tz->trips.passive.flags.valid)
885 		trips++;
886 
887 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE &&
888 			tz->trips.active[i].flags.valid; i++, trips++);
889 
890 	if (tz->trips.passive.flags.valid)
891 		tz->thermal_zone =
892 			thermal_zone_device_register("acpitz", trips, 0, tz,
893 						&acpi_thermal_zone_ops, NULL,
894 						     tz->trips.passive.tsp*100,
895 						     tz->polling_frequency*100);
896 	else
897 		tz->thermal_zone =
898 			thermal_zone_device_register("acpitz", trips, 0, tz,
899 						&acpi_thermal_zone_ops, NULL,
900 						0, tz->polling_frequency*100);
901 	if (IS_ERR(tz->thermal_zone))
902 		return -ENODEV;
903 
904 	result = sysfs_create_link(&tz->device->dev.kobj,
905 				   &tz->thermal_zone->device.kobj, "thermal_zone");
906 	if (result)
907 		return result;
908 
909 	result = sysfs_create_link(&tz->thermal_zone->device.kobj,
910 				   &tz->device->dev.kobj, "device");
911 	if (result)
912 		return result;
913 
914 	status =  acpi_bus_attach_private_data(tz->device->handle,
915 					       tz->thermal_zone);
916 	if (ACPI_FAILURE(status))
917 		return -ENODEV;
918 
919 	tz->tz_enabled = 1;
920 
921 	dev_info(&tz->device->dev, "registered as thermal_zone%d\n",
922 		 tz->thermal_zone->id);
923 	return 0;
924 }
925 
926 static void acpi_thermal_unregister_thermal_zone(struct acpi_thermal *tz)
927 {
928 	sysfs_remove_link(&tz->device->dev.kobj, "thermal_zone");
929 	sysfs_remove_link(&tz->thermal_zone->device.kobj, "device");
930 	thermal_zone_device_unregister(tz->thermal_zone);
931 	tz->thermal_zone = NULL;
932 	acpi_bus_detach_private_data(tz->device->handle);
933 }
934 
935 
936 /* --------------------------------------------------------------------------
937                                  Driver Interface
938    -------------------------------------------------------------------------- */
939 
940 static void acpi_thermal_notify(struct acpi_device *device, u32 event)
941 {
942 	struct acpi_thermal *tz = acpi_driver_data(device);
943 
944 
945 	if (!tz)
946 		return;
947 
948 	switch (event) {
949 	case ACPI_THERMAL_NOTIFY_TEMPERATURE:
950 		acpi_thermal_check(tz);
951 		break;
952 	case ACPI_THERMAL_NOTIFY_THRESHOLDS:
953 		acpi_thermal_trips_update(tz, ACPI_TRIPS_REFRESH_THRESHOLDS);
954 		acpi_thermal_check(tz);
955 		acpi_bus_generate_netlink_event(device->pnp.device_class,
956 						  dev_name(&device->dev), event, 0);
957 		break;
958 	case ACPI_THERMAL_NOTIFY_DEVICES:
959 		acpi_thermal_trips_update(tz, ACPI_TRIPS_REFRESH_DEVICES);
960 		acpi_thermal_check(tz);
961 		acpi_bus_generate_netlink_event(device->pnp.device_class,
962 						  dev_name(&device->dev), event, 0);
963 		break;
964 	default:
965 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
966 				  "Unsupported event [0x%x]\n", event));
967 		break;
968 	}
969 }
970 
971 /*
972  * On some platforms, the AML code has dependency about
973  * the evaluating order of _TMP and _CRT/_HOT/_PSV/_ACx.
974  * 1. On HP Pavilion G4-1016tx, _TMP must be invoked after
975  *    /_CRT/_HOT/_PSV/_ACx, or else system will be power off.
976  * 2. On HP Compaq 6715b/6715s, the return value of _PSV is 0
977  *    if _TMP has never been evaluated.
978  *
979  * As this dependency is totally transparent to OS, evaluate
980  * all of them once, in the order of _CRT/_HOT/_PSV/_ACx,
981  * _TMP, before they are actually used.
982  */
983 static void acpi_thermal_aml_dependency_fix(struct acpi_thermal *tz)
984 {
985 	acpi_handle handle = tz->device->handle;
986 	unsigned long long value;
987 	int i;
988 
989 	acpi_evaluate_integer(handle, "_CRT", NULL, &value);
990 	acpi_evaluate_integer(handle, "_HOT", NULL, &value);
991 	acpi_evaluate_integer(handle, "_PSV", NULL, &value);
992 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
993 		char name[5] = { '_', 'A', 'C', ('0' + i), '\0' };
994 		acpi_status status;
995 
996 		status = acpi_evaluate_integer(handle, name, NULL, &value);
997 		if (status == AE_NOT_FOUND)
998 			break;
999 	}
1000 	acpi_evaluate_integer(handle, "_TMP", NULL, &value);
1001 }
1002 
1003 static int acpi_thermal_get_info(struct acpi_thermal *tz)
1004 {
1005 	int result = 0;
1006 
1007 
1008 	if (!tz)
1009 		return -EINVAL;
1010 
1011 	acpi_thermal_aml_dependency_fix(tz);
1012 
1013 	/* Get trip points [_CRT, _PSV, etc.] (required) */
1014 	result = acpi_thermal_get_trip_points(tz);
1015 	if (result)
1016 		return result;
1017 
1018 	/* Get temperature [_TMP] (required) */
1019 	result = acpi_thermal_get_temperature(tz);
1020 	if (result)
1021 		return result;
1022 
1023 	/* Set the cooling mode [_SCP] to active cooling (default) */
1024 	result = acpi_thermal_set_cooling_mode(tz, ACPI_THERMAL_MODE_ACTIVE);
1025 	if (!result)
1026 		tz->flags.cooling_mode = 1;
1027 
1028 	/* Get default polling frequency [_TZP] (optional) */
1029 	if (tzp)
1030 		tz->polling_frequency = tzp;
1031 	else
1032 		acpi_thermal_get_polling_frequency(tz);
1033 
1034 	return 0;
1035 }
1036 
1037 /*
1038  * The exact offset between Kelvin and degree Celsius is 273.15. However ACPI
1039  * handles temperature values with a single decimal place. As a consequence,
1040  * some implementations use an offset of 273.1 and others use an offset of
1041  * 273.2. Try to find out which one is being used, to present the most
1042  * accurate and visually appealing number.
1043  *
1044  * The heuristic below should work for all ACPI thermal zones which have a
1045  * critical trip point with a value being a multiple of 0.5 degree Celsius.
1046  */
1047 static void acpi_thermal_guess_offset(struct acpi_thermal *tz)
1048 {
1049 	if (tz->trips.critical.flags.valid &&
1050 	    (tz->trips.critical.temperature % 5) == 1)
1051 		tz->kelvin_offset = 2731;
1052 	else
1053 		tz->kelvin_offset = 2732;
1054 }
1055 
1056 static void acpi_thermal_check_fn(struct work_struct *work)
1057 {
1058 	struct acpi_thermal *tz = container_of(work, struct acpi_thermal,
1059 					       thermal_check_work);
1060 	acpi_thermal_check(tz);
1061 }
1062 
1063 static int acpi_thermal_add(struct acpi_device *device)
1064 {
1065 	int result = 0;
1066 	struct acpi_thermal *tz = NULL;
1067 
1068 
1069 	if (!device)
1070 		return -EINVAL;
1071 
1072 	tz = kzalloc(sizeof(struct acpi_thermal), GFP_KERNEL);
1073 	if (!tz)
1074 		return -ENOMEM;
1075 
1076 	tz->device = device;
1077 	strcpy(tz->name, device->pnp.bus_id);
1078 	strcpy(acpi_device_name(device), ACPI_THERMAL_DEVICE_NAME);
1079 	strcpy(acpi_device_class(device), ACPI_THERMAL_CLASS);
1080 	device->driver_data = tz;
1081 
1082 	result = acpi_thermal_get_info(tz);
1083 	if (result)
1084 		goto free_memory;
1085 
1086 	acpi_thermal_guess_offset(tz);
1087 
1088 	result = acpi_thermal_register_thermal_zone(tz);
1089 	if (result)
1090 		goto free_memory;
1091 
1092 	INIT_WORK(&tz->thermal_check_work, acpi_thermal_check_fn);
1093 
1094 	pr_info(PREFIX "%s [%s] (%ld C)\n", acpi_device_name(device),
1095 		acpi_device_bid(device), DECI_KELVIN_TO_CELSIUS(tz->temperature));
1096 	goto end;
1097 
1098 free_memory:
1099 	kfree(tz);
1100 end:
1101 	return result;
1102 }
1103 
1104 static int acpi_thermal_remove(struct acpi_device *device)
1105 {
1106 	struct acpi_thermal *tz = NULL;
1107 
1108 	if (!device || !acpi_driver_data(device))
1109 		return -EINVAL;
1110 
1111 	flush_workqueue(acpi_thermal_pm_queue);
1112 	tz = acpi_driver_data(device);
1113 
1114 	acpi_thermal_unregister_thermal_zone(tz);
1115 	kfree(tz);
1116 	return 0;
1117 }
1118 
1119 #ifdef CONFIG_PM_SLEEP
1120 static int acpi_thermal_suspend(struct device *dev)
1121 {
1122 	/* Make sure the previously queued thermal check work has been done */
1123 	flush_workqueue(acpi_thermal_pm_queue);
1124 	return 0;
1125 }
1126 
1127 static int acpi_thermal_resume(struct device *dev)
1128 {
1129 	struct acpi_thermal *tz;
1130 	int i, j, power_state, result;
1131 
1132 	if (!dev)
1133 		return -EINVAL;
1134 
1135 	tz = acpi_driver_data(to_acpi_device(dev));
1136 	if (!tz)
1137 		return -EINVAL;
1138 
1139 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
1140 		if (!(&tz->trips.active[i]))
1141 			break;
1142 		if (!tz->trips.active[i].flags.valid)
1143 			break;
1144 		tz->trips.active[i].flags.enabled = 1;
1145 		for (j = 0; j < tz->trips.active[i].devices.count; j++) {
1146 			result = acpi_bus_update_power(
1147 					tz->trips.active[i].devices.handles[j],
1148 					&power_state);
1149 			if (result || (power_state != ACPI_STATE_D0)) {
1150 				tz->trips.active[i].flags.enabled = 0;
1151 				break;
1152 			}
1153 		}
1154 		tz->state.active |= tz->trips.active[i].flags.enabled;
1155 	}
1156 
1157 	queue_work(acpi_thermal_pm_queue, &tz->thermal_check_work);
1158 
1159 	return AE_OK;
1160 }
1161 #endif
1162 
1163 static int thermal_act(const struct dmi_system_id *d) {
1164 
1165 	if (act == 0) {
1166 		pr_notice(PREFIX "%s detected: "
1167 			  "disabling all active thermal trip points\n", d->ident);
1168 		act = -1;
1169 	}
1170 	return 0;
1171 }
1172 static int thermal_nocrt(const struct dmi_system_id *d) {
1173 
1174 	pr_notice(PREFIX "%s detected: "
1175 		  "disabling all critical thermal trip point actions.\n", d->ident);
1176 	nocrt = 1;
1177 	return 0;
1178 }
1179 static int thermal_tzp(const struct dmi_system_id *d) {
1180 
1181 	if (tzp == 0) {
1182 		pr_notice(PREFIX "%s detected: "
1183 			  "enabling thermal zone polling\n", d->ident);
1184 		tzp = 300;	/* 300 dS = 30 Seconds */
1185 	}
1186 	return 0;
1187 }
1188 static int thermal_psv(const struct dmi_system_id *d) {
1189 
1190 	if (psv == 0) {
1191 		pr_notice(PREFIX "%s detected: "
1192 			  "disabling all passive thermal trip points\n", d->ident);
1193 		psv = -1;
1194 	}
1195 	return 0;
1196 }
1197 
1198 static const struct dmi_system_id thermal_dmi_table[] __initconst = {
1199 	/*
1200 	 * Award BIOS on this AOpen makes thermal control almost worthless.
1201 	 * http://bugzilla.kernel.org/show_bug.cgi?id=8842
1202 	 */
1203 	{
1204 	 .callback = thermal_act,
1205 	 .ident = "AOpen i915GMm-HFS",
1206 	 .matches = {
1207 		DMI_MATCH(DMI_BOARD_VENDOR, "AOpen"),
1208 		DMI_MATCH(DMI_BOARD_NAME, "i915GMm-HFS"),
1209 		},
1210 	},
1211 	{
1212 	 .callback = thermal_psv,
1213 	 .ident = "AOpen i915GMm-HFS",
1214 	 .matches = {
1215 		DMI_MATCH(DMI_BOARD_VENDOR, "AOpen"),
1216 		DMI_MATCH(DMI_BOARD_NAME, "i915GMm-HFS"),
1217 		},
1218 	},
1219 	{
1220 	 .callback = thermal_tzp,
1221 	 .ident = "AOpen i915GMm-HFS",
1222 	 .matches = {
1223 		DMI_MATCH(DMI_BOARD_VENDOR, "AOpen"),
1224 		DMI_MATCH(DMI_BOARD_NAME, "i915GMm-HFS"),
1225 		},
1226 	},
1227 	{
1228 	 .callback = thermal_nocrt,
1229 	 .ident = "Gigabyte GA-7ZX",
1230 	 .matches = {
1231 		DMI_MATCH(DMI_BOARD_VENDOR, "Gigabyte Technology Co., Ltd."),
1232 		DMI_MATCH(DMI_BOARD_NAME, "7ZX"),
1233 		},
1234 	},
1235 	{}
1236 };
1237 
1238 static int __init acpi_thermal_init(void)
1239 {
1240 	int result = 0;
1241 
1242 	dmi_check_system(thermal_dmi_table);
1243 
1244 	if (off) {
1245 		pr_notice(PREFIX "thermal control disabled\n");
1246 		return -ENODEV;
1247 	}
1248 
1249 	acpi_thermal_pm_queue = alloc_workqueue("acpi_thermal_pm",
1250 						WQ_HIGHPRI | WQ_MEM_RECLAIM, 0);
1251 	if (!acpi_thermal_pm_queue)
1252 		return -ENODEV;
1253 
1254 	result = acpi_bus_register_driver(&acpi_thermal_driver);
1255 	if (result < 0) {
1256 		destroy_workqueue(acpi_thermal_pm_queue);
1257 		return -ENODEV;
1258 	}
1259 
1260 	return 0;
1261 }
1262 
1263 static void __exit acpi_thermal_exit(void)
1264 {
1265 	acpi_bus_unregister_driver(&acpi_thermal_driver);
1266 	destroy_workqueue(acpi_thermal_pm_queue);
1267 
1268 	return;
1269 }
1270 
1271 module_init(acpi_thermal_init);
1272 module_exit(acpi_thermal_exit);
1273