xref: /openbmc/linux/drivers/acpi/thermal.c (revision 11788d9b)
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 #include <linux/units.h>
31 
32 #define PREFIX "ACPI: "
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 #define _COMPONENT		ACPI_THERMAL_COMPONENT
47 ACPI_MODULE_NAME("thermal");
48 
49 MODULE_AUTHOR("Paul Diefenbaugh");
50 MODULE_DESCRIPTION("ACPI Thermal Zone Driver");
51 MODULE_LICENSE("GPL");
52 
53 static int act;
54 module_param(act, int, 0644);
55 MODULE_PARM_DESC(act, "Disable or override all lowest active trip points.");
56 
57 static int crt;
58 module_param(crt, int, 0644);
59 MODULE_PARM_DESC(crt, "Disable or lower all critical trip points.");
60 
61 static int tzp;
62 module_param(tzp, int, 0444);
63 MODULE_PARM_DESC(tzp, "Thermal zone polling frequency, in 1/10 seconds.");
64 
65 static int nocrt;
66 module_param(nocrt, int, 0);
67 MODULE_PARM_DESC(nocrt, "Set to take no action upon ACPI thermal zone critical trips points.");
68 
69 static int off;
70 module_param(off, int, 0);
71 MODULE_PARM_DESC(off, "Set to disable ACPI thermal support.");
72 
73 static int psv;
74 module_param(psv, int, 0644);
75 MODULE_PARM_DESC(psv, "Disable or override all passive trip points.");
76 
77 static struct workqueue_struct *acpi_thermal_pm_queue;
78 
79 static int acpi_thermal_add(struct acpi_device *device);
80 static int acpi_thermal_remove(struct acpi_device *device);
81 static void acpi_thermal_notify(struct acpi_device *device, u32 event);
82 
83 static const struct acpi_device_id  thermal_device_ids[] = {
84 	{ACPI_THERMAL_HID, 0},
85 	{"", 0},
86 };
87 MODULE_DEVICE_TABLE(acpi, thermal_device_ids);
88 
89 #ifdef CONFIG_PM_SLEEP
90 static int acpi_thermal_suspend(struct device *dev);
91 static int acpi_thermal_resume(struct device *dev);
92 #else
93 #define acpi_thermal_suspend NULL
94 #define acpi_thermal_resume NULL
95 #endif
96 static SIMPLE_DEV_PM_OPS(acpi_thermal_pm, acpi_thermal_suspend, acpi_thermal_resume);
97 
98 static struct acpi_driver acpi_thermal_driver = {
99 	.name = "thermal",
100 	.class = ACPI_THERMAL_CLASS,
101 	.ids = thermal_device_ids,
102 	.ops = {
103 		.add = acpi_thermal_add,
104 		.remove = acpi_thermal_remove,
105 		.notify = acpi_thermal_notify,
106 		},
107 	.drv.pm = &acpi_thermal_pm,
108 };
109 
110 struct acpi_thermal_state {
111 	u8 critical:1;
112 	u8 hot:1;
113 	u8 passive:1;
114 	u8 active:1;
115 	u8 reserved:4;
116 	int active_index;
117 };
118 
119 struct acpi_thermal_state_flags {
120 	u8 valid:1;
121 	u8 enabled:1;
122 	u8 reserved:6;
123 };
124 
125 struct acpi_thermal_critical {
126 	struct acpi_thermal_state_flags flags;
127 	unsigned long temperature;
128 };
129 
130 struct acpi_thermal_hot {
131 	struct acpi_thermal_state_flags flags;
132 	unsigned long temperature;
133 };
134 
135 struct acpi_thermal_passive {
136 	struct acpi_thermal_state_flags flags;
137 	unsigned long temperature;
138 	unsigned long tc1;
139 	unsigned long tc2;
140 	unsigned long tsp;
141 	struct acpi_handle_list devices;
142 };
143 
144 struct acpi_thermal_active {
145 	struct acpi_thermal_state_flags flags;
146 	unsigned long temperature;
147 	struct acpi_handle_list devices;
148 };
149 
150 struct acpi_thermal_trips {
151 	struct acpi_thermal_critical critical;
152 	struct acpi_thermal_hot hot;
153 	struct acpi_thermal_passive passive;
154 	struct acpi_thermal_active active[ACPI_THERMAL_MAX_ACTIVE];
155 };
156 
157 struct acpi_thermal_flags {
158 	u8 cooling_mode:1;	/* _SCP */
159 	u8 devices:1;		/* _TZD */
160 	u8 reserved:6;
161 };
162 
163 struct acpi_thermal {
164 	struct acpi_device * device;
165 	acpi_bus_id name;
166 	unsigned long temperature;
167 	unsigned long last_temperature;
168 	unsigned long polling_frequency;
169 	volatile u8 zombie;
170 	struct acpi_thermal_flags flags;
171 	struct acpi_thermal_state state;
172 	struct acpi_thermal_trips trips;
173 	struct acpi_handle_list devices;
174 	struct thermal_zone_device *thermal_zone;
175 	int kelvin_offset;	/* in millidegrees */
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_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, str)	\
256 do {	\
257 	if (flags != ACPI_TRIPS_INIT)	\
258 		ACPI_EXCEPTION((AE_INFO, AE_ERROR,	\
259 		"ACPI thermal trip point %s changed\n"	\
260 		"Please send acpidump to linux-acpi@vger.kernel.org", 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_DEBUG_PRINT((ACPI_DB_INFO,
285 					  "No critical threshold\n"));
286 		} else if (tmp <= 2732) {
287 			pr_warn(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_DEBUG_PRINT((ACPI_DB_INFO,
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_warn(PREFIX "Critical threshold %d C\n",
307 						crt);
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_DEBUG_PRINT((ACPI_DB_INFO,
320 					"No hot threshold\n"));
321 		} else {
322 			tz->trips.hot.temperature = tmp;
323 			tz->trips.hot.flags.valid = 1;
324 			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
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 			pr_warn(PREFIX "Invalid passive threshold\n");
380 			tz->trips.passive.flags.valid = 0;
381 		}
382 		else
383 			tz->trips.passive.flags.valid = 1;
384 
385 		if (memcmp(&tz->trips.passive.devices, &devices,
386 				sizeof(struct acpi_handle_list))) {
387 			memcpy(&tz->trips.passive.devices, &devices,
388 				sizeof(struct acpi_handle_list));
389 			ACPI_THERMAL_TRIPS_EXCEPTION(flag, "device");
390 		}
391 	}
392 	if ((flag & ACPI_TRIPS_PASSIVE) || (flag & ACPI_TRIPS_DEVICES)) {
393 		if (valid != tz->trips.passive.flags.valid)
394 				ACPI_THERMAL_TRIPS_EXCEPTION(flag, "state");
395 	}
396 
397 	/* Active (optional) */
398 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
399 		char name[5] = { '_', 'A', 'C', ('0' + i), '\0' };
400 		valid = tz->trips.active[i].flags.valid;
401 
402 		if (act == -1)
403 			break; /* disable all active trip points */
404 
405 		if ((flag == ACPI_TRIPS_INIT) || ((flag & ACPI_TRIPS_ACTIVE) &&
406 			tz->trips.active[i].flags.valid)) {
407 			status = acpi_evaluate_integer(tz->device->handle,
408 							name, NULL, &tmp);
409 			if (ACPI_FAILURE(status)) {
410 				tz->trips.active[i].flags.valid = 0;
411 				if (i == 0)
412 					break;
413 				if (act <= 0)
414 					break;
415 				if (i == 1)
416 					tz->trips.active[0].temperature =
417 						celsius_to_deci_kelvin(act);
418 				else
419 					/*
420 					 * Don't allow override higher than
421 					 * the next higher trip point
422 					 */
423 					tz->trips.active[i - 1].temperature =
424 						(tz->trips.active[i - 2].temperature <
425 						celsius_to_deci_kelvin(act) ?
426 						tz->trips.active[i - 2].temperature :
427 						celsius_to_deci_kelvin(act));
428 				break;
429 			} else {
430 				tz->trips.active[i].temperature = tmp;
431 				tz->trips.active[i].flags.valid = 1;
432 			}
433 		}
434 
435 		name[2] = 'L';
436 		if ((flag & ACPI_TRIPS_DEVICES) && tz->trips.active[i].flags.valid ) {
437 			memset(&devices, 0, sizeof(struct acpi_handle_list));
438 			status = acpi_evaluate_reference(tz->device->handle,
439 						name, NULL, &devices);
440 			if (ACPI_FAILURE(status)) {
441 				pr_warn(PREFIX "Invalid active%d threshold\n",
442 					i);
443 				tz->trips.active[i].flags.valid = 0;
444 			}
445 			else
446 				tz->trips.active[i].flags.valid = 1;
447 
448 			if (memcmp(&tz->trips.active[i].devices, &devices,
449 					sizeof(struct acpi_handle_list))) {
450 				memcpy(&tz->trips.active[i].devices, &devices,
451 					sizeof(struct acpi_handle_list));
452 				ACPI_THERMAL_TRIPS_EXCEPTION(flag, "device");
453 			}
454 		}
455 		if ((flag & ACPI_TRIPS_ACTIVE) || (flag & ACPI_TRIPS_DEVICES))
456 			if (valid != tz->trips.active[i].flags.valid)
457 				ACPI_THERMAL_TRIPS_EXCEPTION(flag, "state");
458 
459 		if (!tz->trips.active[i].flags.valid)
460 			break;
461 	}
462 
463 	if (flag & ACPI_TRIPS_DEVICES) {
464 		memset(&devices, 0, sizeof(devices));
465 		status = acpi_evaluate_reference(tz->device->handle, "_TZD",
466 						NULL, &devices);
467 		if (ACPI_SUCCESS(status)
468 		    && memcmp(&tz->devices, &devices, sizeof(devices))) {
469 			tz->devices = devices;
470 			ACPI_THERMAL_TRIPS_EXCEPTION(flag, "device");
471 		}
472 	}
473 
474 	return 0;
475 }
476 
477 static int acpi_thermal_get_trip_points(struct acpi_thermal *tz)
478 {
479 	int i, valid, ret = acpi_thermal_trips_update(tz, ACPI_TRIPS_INIT);
480 
481 	if (ret)
482 		return ret;
483 
484 	valid = tz->trips.critical.flags.valid |
485 		tz->trips.hot.flags.valid |
486 		tz->trips.passive.flags.valid;
487 
488 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++)
489 		valid |= tz->trips.active[i].flags.valid;
490 
491 	if (!valid) {
492 		pr_warn(FW_BUG "No valid trip found\n");
493 		return -ENODEV;
494 	}
495 	return 0;
496 }
497 
498 static void acpi_thermal_check(void *data)
499 {
500 	struct acpi_thermal *tz = data;
501 
502 	thermal_zone_device_update(tz->thermal_zone,
503 				   THERMAL_EVENT_UNSPECIFIED);
504 }
505 
506 /* sys I/F for generic thermal sysfs support */
507 
508 static int thermal_get_temp(struct thermal_zone_device *thermal, int *temp)
509 {
510 	struct acpi_thermal *tz = thermal->devdata;
511 	int result;
512 
513 	if (!tz)
514 		return -EINVAL;
515 
516 	result = acpi_thermal_get_temperature(tz);
517 	if (result)
518 		return result;
519 
520 	*temp = deci_kelvin_to_millicelsius_with_offset(tz->temperature,
521 							tz->kelvin_offset);
522 	return 0;
523 }
524 
525 static int thermal_get_trip_type(struct thermal_zone_device *thermal,
526 				 int trip, enum thermal_trip_type *type)
527 {
528 	struct acpi_thermal *tz = thermal->devdata;
529 	int i;
530 
531 	if (!tz || trip < 0)
532 		return -EINVAL;
533 
534 	if (tz->trips.critical.flags.valid) {
535 		if (!trip) {
536 			*type = THERMAL_TRIP_CRITICAL;
537 			return 0;
538 		}
539 		trip--;
540 	}
541 
542 	if (tz->trips.hot.flags.valid) {
543 		if (!trip) {
544 			*type = THERMAL_TRIP_HOT;
545 			return 0;
546 		}
547 		trip--;
548 	}
549 
550 	if (tz->trips.passive.flags.valid) {
551 		if (!trip) {
552 			*type = THERMAL_TRIP_PASSIVE;
553 			return 0;
554 		}
555 		trip--;
556 	}
557 
558 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE &&
559 		tz->trips.active[i].flags.valid; i++) {
560 		if (!trip) {
561 			*type = THERMAL_TRIP_ACTIVE;
562 			return 0;
563 		}
564 		trip--;
565 	}
566 
567 	return -EINVAL;
568 }
569 
570 static int thermal_get_trip_temp(struct thermal_zone_device *thermal,
571 				 int trip, int *temp)
572 {
573 	struct acpi_thermal *tz = thermal->devdata;
574 	int i;
575 
576 	if (!tz || trip < 0)
577 		return -EINVAL;
578 
579 	if (tz->trips.critical.flags.valid) {
580 		if (!trip) {
581 			*temp = deci_kelvin_to_millicelsius_with_offset(
582 				tz->trips.critical.temperature,
583 				tz->kelvin_offset);
584 			return 0;
585 		}
586 		trip--;
587 	}
588 
589 	if (tz->trips.hot.flags.valid) {
590 		if (!trip) {
591 			*temp = deci_kelvin_to_millicelsius_with_offset(
592 				tz->trips.hot.temperature,
593 				tz->kelvin_offset);
594 			return 0;
595 		}
596 		trip--;
597 	}
598 
599 	if (tz->trips.passive.flags.valid) {
600 		if (!trip) {
601 			*temp = deci_kelvin_to_millicelsius_with_offset(
602 				tz->trips.passive.temperature,
603 				tz->kelvin_offset);
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 			*temp = deci_kelvin_to_millicelsius_with_offset(
613 				tz->trips.active[i].temperature,
614 				tz->kelvin_offset);
615 			return 0;
616 		}
617 		trip--;
618 	}
619 
620 	return -EINVAL;
621 }
622 
623 static int thermal_get_crit_temp(struct thermal_zone_device *thermal,
624 				int *temperature)
625 {
626 	struct acpi_thermal *tz = thermal->devdata;
627 
628 	if (tz->trips.critical.flags.valid) {
629 		*temperature = deci_kelvin_to_millicelsius_with_offset(
630 				tz->trips.critical.temperature,
631 				tz->kelvin_offset);
632 		return 0;
633 	} else
634 		return -EINVAL;
635 }
636 
637 static int thermal_get_trend(struct thermal_zone_device *thermal,
638 				int trip, enum thermal_trend *trend)
639 {
640 	struct acpi_thermal *tz = thermal->devdata;
641 	enum thermal_trip_type type;
642 	int i;
643 
644 	if (thermal_get_trip_type(thermal, trip, &type))
645 		return -EINVAL;
646 
647 	if (type == THERMAL_TRIP_ACTIVE) {
648 		int trip_temp;
649 		int temp = deci_kelvin_to_millicelsius_with_offset(
650 					tz->temperature, tz->kelvin_offset);
651 		if (thermal_get_trip_temp(thermal, trip, &trip_temp))
652 			return -EINVAL;
653 
654 		if (temp > trip_temp) {
655 			*trend = THERMAL_TREND_RAISING;
656 			return 0;
657 		} else {
658 			/* Fall back on default trend */
659 			return -EINVAL;
660 		}
661 	}
662 
663 	/*
664 	 * tz->temperature has already been updated by generic thermal layer,
665 	 * before this callback being invoked
666 	 */
667 	i = (tz->trips.passive.tc1 * (tz->temperature - tz->last_temperature))
668 		+ (tz->trips.passive.tc2
669 		* (tz->temperature - tz->trips.passive.temperature));
670 
671 	if (i > 0)
672 		*trend = THERMAL_TREND_RAISING;
673 	else if (i < 0)
674 		*trend = THERMAL_TREND_DROPPING;
675 	else
676 		*trend = THERMAL_TREND_STABLE;
677 	return 0;
678 }
679 
680 
681 static int thermal_notify(struct thermal_zone_device *thermal, int trip,
682 			   enum thermal_trip_type trip_type)
683 {
684 	u8 type = 0;
685 	struct acpi_thermal *tz = thermal->devdata;
686 
687 	if (trip_type == THERMAL_TRIP_CRITICAL)
688 		type = ACPI_THERMAL_NOTIFY_CRITICAL;
689 	else if (trip_type == THERMAL_TRIP_HOT)
690 		type = ACPI_THERMAL_NOTIFY_HOT;
691 	else
692 		return 0;
693 
694 	acpi_bus_generate_netlink_event(tz->device->pnp.device_class,
695 					dev_name(&tz->device->dev), type, 1);
696 
697 	if (trip_type == THERMAL_TRIP_CRITICAL && nocrt)
698 		return 1;
699 
700 	return 0;
701 }
702 
703 static int acpi_thermal_cooling_device_cb(struct thermal_zone_device *thermal,
704 					struct thermal_cooling_device *cdev,
705 					bool bind)
706 {
707 	struct acpi_device *device = cdev->devdata;
708 	struct acpi_thermal *tz = thermal->devdata;
709 	struct acpi_device *dev;
710 	acpi_status status;
711 	acpi_handle handle;
712 	int i;
713 	int j;
714 	int trip = -1;
715 	int result = 0;
716 
717 	if (tz->trips.critical.flags.valid)
718 		trip++;
719 
720 	if (tz->trips.hot.flags.valid)
721 		trip++;
722 
723 	if (tz->trips.passive.flags.valid) {
724 		trip++;
725 		for (i = 0; i < tz->trips.passive.devices.count;
726 		    i++) {
727 			handle = tz->trips.passive.devices.handles[i];
728 			status = acpi_bus_get_device(handle, &dev);
729 			if (ACPI_FAILURE(status) || dev != device)
730 				continue;
731 			if (bind)
732 				result =
733 					thermal_zone_bind_cooling_device
734 					(thermal, trip, cdev,
735 					 THERMAL_NO_LIMIT, THERMAL_NO_LIMIT,
736 					 THERMAL_WEIGHT_DEFAULT);
737 			else
738 				result =
739 					thermal_zone_unbind_cooling_device
740 					(thermal, trip, cdev);
741 			if (result)
742 				goto failed;
743 		}
744 	}
745 
746 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
747 		if (!tz->trips.active[i].flags.valid)
748 			break;
749 		trip++;
750 		for (j = 0;
751 		    j < tz->trips.active[i].devices.count;
752 		    j++) {
753 			handle = tz->trips.active[i].devices.handles[j];
754 			status = acpi_bus_get_device(handle, &dev);
755 			if (ACPI_FAILURE(status) || dev != device)
756 				continue;
757 			if (bind)
758 				result = thermal_zone_bind_cooling_device
759 					(thermal, trip, cdev,
760 					 THERMAL_NO_LIMIT, THERMAL_NO_LIMIT,
761 					 THERMAL_WEIGHT_DEFAULT);
762 			else
763 				result = thermal_zone_unbind_cooling_device
764 					(thermal, trip, cdev);
765 			if (result)
766 				goto failed;
767 		}
768 	}
769 
770 	for (i = 0; i < tz->devices.count; i++) {
771 		handle = tz->devices.handles[i];
772 		status = acpi_bus_get_device(handle, &dev);
773 		if (ACPI_SUCCESS(status) && (dev == device)) {
774 			if (bind)
775 				result = thermal_zone_bind_cooling_device
776 						(thermal, THERMAL_TRIPS_NONE,
777 						 cdev, THERMAL_NO_LIMIT,
778 						 THERMAL_NO_LIMIT,
779 						 THERMAL_WEIGHT_DEFAULT);
780 			else
781 				result = thermal_zone_unbind_cooling_device
782 						(thermal, THERMAL_TRIPS_NONE,
783 						 cdev);
784 			if (result)
785 				goto failed;
786 		}
787 	}
788 
789 failed:
790 	return result;
791 }
792 
793 static int
794 acpi_thermal_bind_cooling_device(struct thermal_zone_device *thermal,
795 					struct thermal_cooling_device *cdev)
796 {
797 	return acpi_thermal_cooling_device_cb(thermal, cdev, true);
798 }
799 
800 static int
801 acpi_thermal_unbind_cooling_device(struct thermal_zone_device *thermal,
802 					struct thermal_cooling_device *cdev)
803 {
804 	return acpi_thermal_cooling_device_cb(thermal, cdev, false);
805 }
806 
807 static struct thermal_zone_device_ops acpi_thermal_zone_ops = {
808 	.bind = acpi_thermal_bind_cooling_device,
809 	.unbind	= acpi_thermal_unbind_cooling_device,
810 	.get_temp = thermal_get_temp,
811 	.get_trip_type = thermal_get_trip_type,
812 	.get_trip_temp = thermal_get_trip_temp,
813 	.get_crit_temp = thermal_get_crit_temp,
814 	.get_trend = thermal_get_trend,
815 	.notify = thermal_notify,
816 };
817 
818 static int acpi_thermal_register_thermal_zone(struct acpi_thermal *tz)
819 {
820 	int trips = 0;
821 	int result;
822 	acpi_status status;
823 	int i;
824 
825 	if (tz->trips.critical.flags.valid)
826 		trips++;
827 
828 	if (tz->trips.hot.flags.valid)
829 		trips++;
830 
831 	if (tz->trips.passive.flags.valid)
832 		trips++;
833 
834 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE &&
835 			tz->trips.active[i].flags.valid; i++, trips++);
836 
837 	if (tz->trips.passive.flags.valid)
838 		tz->thermal_zone =
839 			thermal_zone_device_register("acpitz", trips, 0, tz,
840 						&acpi_thermal_zone_ops, NULL,
841 						     tz->trips.passive.tsp*100,
842 						     tz->polling_frequency*100);
843 	else
844 		tz->thermal_zone =
845 			thermal_zone_device_register("acpitz", trips, 0, tz,
846 						&acpi_thermal_zone_ops, NULL,
847 						0, tz->polling_frequency*100);
848 	if (IS_ERR(tz->thermal_zone))
849 		return -ENODEV;
850 
851 	result = sysfs_create_link(&tz->device->dev.kobj,
852 				   &tz->thermal_zone->device.kobj, "thermal_zone");
853 	if (result)
854 		goto unregister_tzd;
855 
856 	result = sysfs_create_link(&tz->thermal_zone->device.kobj,
857 				   &tz->device->dev.kobj, "device");
858 	if (result)
859 		goto remove_tz_link;
860 
861 	status =  acpi_bus_attach_private_data(tz->device->handle,
862 					       tz->thermal_zone);
863 	if (ACPI_FAILURE(status)) {
864 		result = -ENODEV;
865 		goto remove_dev_link;
866 	}
867 
868 	result = thermal_zone_device_enable(tz->thermal_zone);
869 	if (result)
870 		goto acpi_bus_detach;
871 
872 	dev_info(&tz->device->dev, "registered as thermal_zone%d\n",
873 		 tz->thermal_zone->id);
874 
875 	return 0;
876 
877 acpi_bus_detach:
878 	acpi_bus_detach_private_data(tz->device->handle);
879 remove_dev_link:
880 	sysfs_remove_link(&tz->thermal_zone->device.kobj, "device");
881 remove_tz_link:
882 	sysfs_remove_link(&tz->device->dev.kobj, "thermal_zone");
883 unregister_tzd:
884 	thermal_zone_device_unregister(tz->thermal_zone);
885 
886 	return result;
887 }
888 
889 static void acpi_thermal_unregister_thermal_zone(struct acpi_thermal *tz)
890 {
891 	sysfs_remove_link(&tz->device->dev.kobj, "thermal_zone");
892 	sysfs_remove_link(&tz->thermal_zone->device.kobj, "device");
893 	thermal_zone_device_unregister(tz->thermal_zone);
894 	tz->thermal_zone = NULL;
895 	acpi_bus_detach_private_data(tz->device->handle);
896 }
897 
898 
899 /* --------------------------------------------------------------------------
900                                  Driver Interface
901    -------------------------------------------------------------------------- */
902 
903 static void acpi_thermal_notify(struct acpi_device *device, u32 event)
904 {
905 	struct acpi_thermal *tz = acpi_driver_data(device);
906 
907 
908 	if (!tz)
909 		return;
910 
911 	switch (event) {
912 	case ACPI_THERMAL_NOTIFY_TEMPERATURE:
913 		acpi_thermal_check(tz);
914 		break;
915 	case ACPI_THERMAL_NOTIFY_THRESHOLDS:
916 		acpi_thermal_trips_update(tz, ACPI_TRIPS_REFRESH_THRESHOLDS);
917 		acpi_thermal_check(tz);
918 		acpi_bus_generate_netlink_event(device->pnp.device_class,
919 						  dev_name(&device->dev), event, 0);
920 		break;
921 	case ACPI_THERMAL_NOTIFY_DEVICES:
922 		acpi_thermal_trips_update(tz, ACPI_TRIPS_REFRESH_DEVICES);
923 		acpi_thermal_check(tz);
924 		acpi_bus_generate_netlink_event(device->pnp.device_class,
925 						  dev_name(&device->dev), event, 0);
926 		break;
927 	default:
928 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
929 				  "Unsupported event [0x%x]\n", event));
930 		break;
931 	}
932 }
933 
934 /*
935  * On some platforms, the AML code has dependency about
936  * the evaluating order of _TMP and _CRT/_HOT/_PSV/_ACx.
937  * 1. On HP Pavilion G4-1016tx, _TMP must be invoked after
938  *    /_CRT/_HOT/_PSV/_ACx, or else system will be power off.
939  * 2. On HP Compaq 6715b/6715s, the return value of _PSV is 0
940  *    if _TMP has never been evaluated.
941  *
942  * As this dependency is totally transparent to OS, evaluate
943  * all of them once, in the order of _CRT/_HOT/_PSV/_ACx,
944  * _TMP, before they are actually used.
945  */
946 static void acpi_thermal_aml_dependency_fix(struct acpi_thermal *tz)
947 {
948 	acpi_handle handle = tz->device->handle;
949 	unsigned long long value;
950 	int i;
951 
952 	acpi_evaluate_integer(handle, "_CRT", NULL, &value);
953 	acpi_evaluate_integer(handle, "_HOT", NULL, &value);
954 	acpi_evaluate_integer(handle, "_PSV", NULL, &value);
955 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
956 		char name[5] = { '_', 'A', 'C', ('0' + i), '\0' };
957 		acpi_status status;
958 
959 		status = acpi_evaluate_integer(handle, name, NULL, &value);
960 		if (status == AE_NOT_FOUND)
961 			break;
962 	}
963 	acpi_evaluate_integer(handle, "_TMP", NULL, &value);
964 }
965 
966 static int acpi_thermal_get_info(struct acpi_thermal *tz)
967 {
968 	int result = 0;
969 
970 
971 	if (!tz)
972 		return -EINVAL;
973 
974 	acpi_thermal_aml_dependency_fix(tz);
975 
976 	/* Get trip points [_CRT, _PSV, etc.] (required) */
977 	result = acpi_thermal_get_trip_points(tz);
978 	if (result)
979 		return result;
980 
981 	/* Get temperature [_TMP] (required) */
982 	result = acpi_thermal_get_temperature(tz);
983 	if (result)
984 		return result;
985 
986 	/* Set the cooling mode [_SCP] to active cooling (default) */
987 	result = acpi_thermal_set_cooling_mode(tz, ACPI_THERMAL_MODE_ACTIVE);
988 	if (!result)
989 		tz->flags.cooling_mode = 1;
990 
991 	/* Get default polling frequency [_TZP] (optional) */
992 	if (tzp)
993 		tz->polling_frequency = tzp;
994 	else
995 		acpi_thermal_get_polling_frequency(tz);
996 
997 	return 0;
998 }
999 
1000 /*
1001  * The exact offset between Kelvin and degree Celsius is 273.15. However ACPI
1002  * handles temperature values with a single decimal place. As a consequence,
1003  * some implementations use an offset of 273.1 and others use an offset of
1004  * 273.2. Try to find out which one is being used, to present the most
1005  * accurate and visually appealing number.
1006  *
1007  * The heuristic below should work for all ACPI thermal zones which have a
1008  * critical trip point with a value being a multiple of 0.5 degree Celsius.
1009  */
1010 static void acpi_thermal_guess_offset(struct acpi_thermal *tz)
1011 {
1012 	if (tz->trips.critical.flags.valid &&
1013 	    (tz->trips.critical.temperature % 5) == 1)
1014 		tz->kelvin_offset = 273100;
1015 	else
1016 		tz->kelvin_offset = 273200;
1017 }
1018 
1019 static void acpi_thermal_check_fn(struct work_struct *work)
1020 {
1021 	struct acpi_thermal *tz = container_of(work, struct acpi_thermal,
1022 					       thermal_check_work);
1023 	acpi_thermal_check(tz);
1024 }
1025 
1026 static int acpi_thermal_add(struct acpi_device *device)
1027 {
1028 	int result = 0;
1029 	struct acpi_thermal *tz = NULL;
1030 
1031 
1032 	if (!device)
1033 		return -EINVAL;
1034 
1035 	tz = kzalloc(sizeof(struct acpi_thermal), GFP_KERNEL);
1036 	if (!tz)
1037 		return -ENOMEM;
1038 
1039 	tz->device = device;
1040 	strcpy(tz->name, device->pnp.bus_id);
1041 	strcpy(acpi_device_name(device), ACPI_THERMAL_DEVICE_NAME);
1042 	strcpy(acpi_device_class(device), ACPI_THERMAL_CLASS);
1043 	device->driver_data = tz;
1044 
1045 	result = acpi_thermal_get_info(tz);
1046 	if (result)
1047 		goto free_memory;
1048 
1049 	acpi_thermal_guess_offset(tz);
1050 
1051 	result = acpi_thermal_register_thermal_zone(tz);
1052 	if (result)
1053 		goto free_memory;
1054 
1055 	INIT_WORK(&tz->thermal_check_work, acpi_thermal_check_fn);
1056 
1057 	pr_info(PREFIX "%s [%s] (%ld C)\n", acpi_device_name(device),
1058 		acpi_device_bid(device), deci_kelvin_to_celsius(tz->temperature));
1059 	goto end;
1060 
1061 free_memory:
1062 	kfree(tz);
1063 end:
1064 	return result;
1065 }
1066 
1067 static int acpi_thermal_remove(struct acpi_device *device)
1068 {
1069 	struct acpi_thermal *tz = NULL;
1070 
1071 	if (!device || !acpi_driver_data(device))
1072 		return -EINVAL;
1073 
1074 	flush_workqueue(acpi_thermal_pm_queue);
1075 	tz = acpi_driver_data(device);
1076 
1077 	acpi_thermal_unregister_thermal_zone(tz);
1078 	kfree(tz);
1079 	return 0;
1080 }
1081 
1082 #ifdef CONFIG_PM_SLEEP
1083 static int acpi_thermal_suspend(struct device *dev)
1084 {
1085 	/* Make sure the previously queued thermal check work has been done */
1086 	flush_workqueue(acpi_thermal_pm_queue);
1087 	return 0;
1088 }
1089 
1090 static int acpi_thermal_resume(struct device *dev)
1091 {
1092 	struct acpi_thermal *tz;
1093 	int i, j, power_state, result;
1094 
1095 	if (!dev)
1096 		return -EINVAL;
1097 
1098 	tz = acpi_driver_data(to_acpi_device(dev));
1099 	if (!tz)
1100 		return -EINVAL;
1101 
1102 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
1103 		if (!(&tz->trips.active[i]))
1104 			break;
1105 		if (!tz->trips.active[i].flags.valid)
1106 			break;
1107 		tz->trips.active[i].flags.enabled = 1;
1108 		for (j = 0; j < tz->trips.active[i].devices.count; j++) {
1109 			result = acpi_bus_update_power(
1110 					tz->trips.active[i].devices.handles[j],
1111 					&power_state);
1112 			if (result || (power_state != ACPI_STATE_D0)) {
1113 				tz->trips.active[i].flags.enabled = 0;
1114 				break;
1115 			}
1116 		}
1117 		tz->state.active |= tz->trips.active[i].flags.enabled;
1118 	}
1119 
1120 	queue_work(acpi_thermal_pm_queue, &tz->thermal_check_work);
1121 
1122 	return AE_OK;
1123 }
1124 #endif
1125 
1126 static int thermal_act(const struct dmi_system_id *d) {
1127 
1128 	if (act == 0) {
1129 		pr_notice(PREFIX "%s detected: "
1130 			  "disabling all active thermal trip points\n", d->ident);
1131 		act = -1;
1132 	}
1133 	return 0;
1134 }
1135 static int thermal_nocrt(const struct dmi_system_id *d) {
1136 
1137 	pr_notice(PREFIX "%s detected: "
1138 		  "disabling all critical thermal trip point actions.\n", d->ident);
1139 	nocrt = 1;
1140 	return 0;
1141 }
1142 static int thermal_tzp(const struct dmi_system_id *d) {
1143 
1144 	if (tzp == 0) {
1145 		pr_notice(PREFIX "%s detected: "
1146 			  "enabling thermal zone polling\n", d->ident);
1147 		tzp = 300;	/* 300 dS = 30 Seconds */
1148 	}
1149 	return 0;
1150 }
1151 static int thermal_psv(const struct dmi_system_id *d) {
1152 
1153 	if (psv == 0) {
1154 		pr_notice(PREFIX "%s detected: "
1155 			  "disabling all passive thermal trip points\n", d->ident);
1156 		psv = -1;
1157 	}
1158 	return 0;
1159 }
1160 
1161 static const struct dmi_system_id thermal_dmi_table[] __initconst = {
1162 	/*
1163 	 * Award BIOS on this AOpen makes thermal control almost worthless.
1164 	 * http://bugzilla.kernel.org/show_bug.cgi?id=8842
1165 	 */
1166 	{
1167 	 .callback = thermal_act,
1168 	 .ident = "AOpen i915GMm-HFS",
1169 	 .matches = {
1170 		DMI_MATCH(DMI_BOARD_VENDOR, "AOpen"),
1171 		DMI_MATCH(DMI_BOARD_NAME, "i915GMm-HFS"),
1172 		},
1173 	},
1174 	{
1175 	 .callback = thermal_psv,
1176 	 .ident = "AOpen i915GMm-HFS",
1177 	 .matches = {
1178 		DMI_MATCH(DMI_BOARD_VENDOR, "AOpen"),
1179 		DMI_MATCH(DMI_BOARD_NAME, "i915GMm-HFS"),
1180 		},
1181 	},
1182 	{
1183 	 .callback = thermal_tzp,
1184 	 .ident = "AOpen i915GMm-HFS",
1185 	 .matches = {
1186 		DMI_MATCH(DMI_BOARD_VENDOR, "AOpen"),
1187 		DMI_MATCH(DMI_BOARD_NAME, "i915GMm-HFS"),
1188 		},
1189 	},
1190 	{
1191 	 .callback = thermal_nocrt,
1192 	 .ident = "Gigabyte GA-7ZX",
1193 	 .matches = {
1194 		DMI_MATCH(DMI_BOARD_VENDOR, "Gigabyte Technology Co., Ltd."),
1195 		DMI_MATCH(DMI_BOARD_NAME, "7ZX"),
1196 		},
1197 	},
1198 	{}
1199 };
1200 
1201 static int __init acpi_thermal_init(void)
1202 {
1203 	int result = 0;
1204 
1205 	dmi_check_system(thermal_dmi_table);
1206 
1207 	if (off) {
1208 		pr_notice(PREFIX "thermal control disabled\n");
1209 		return -ENODEV;
1210 	}
1211 
1212 	acpi_thermal_pm_queue = alloc_workqueue("acpi_thermal_pm",
1213 						WQ_HIGHPRI | WQ_MEM_RECLAIM, 0);
1214 	if (!acpi_thermal_pm_queue)
1215 		return -ENODEV;
1216 
1217 	result = acpi_bus_register_driver(&acpi_thermal_driver);
1218 	if (result < 0) {
1219 		destroy_workqueue(acpi_thermal_pm_queue);
1220 		return -ENODEV;
1221 	}
1222 
1223 	return 0;
1224 }
1225 
1226 static void __exit acpi_thermal_exit(void)
1227 {
1228 	acpi_bus_unregister_driver(&acpi_thermal_driver);
1229 	destroy_workqueue(acpi_thermal_pm_queue);
1230 
1231 	return;
1232 }
1233 
1234 module_init(acpi_thermal_init);
1235 module_exit(acpi_thermal_exit);
1236