xref: /openbmc/linux/drivers/acpi/thermal.c (revision 8fdff1dc)
1 /*
2  *  acpi_thermal.c - ACPI Thermal Zone Driver ($Revision: 41 $)
3  *
4  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
5  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
6  *
7  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
8  *
9  *  This program is free software; you can redistribute it and/or modify
10  *  it under the terms of the GNU General Public License as published by
11  *  the Free Software Foundation; either version 2 of the License, or (at
12  *  your option) any later version.
13  *
14  *  This program is distributed in the hope that it will be useful, but
15  *  WITHOUT ANY WARRANTY; without even the implied warranty of
16  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17  *  General Public License for more details.
18  *
19  *  You should have received a copy of the GNU General Public License along
20  *  with this program; if not, write to the Free Software Foundation, Inc.,
21  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
22  *
23  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
24  *
25  *  This driver fully implements the ACPI thermal policy as described in the
26  *  ACPI 2.0 Specification.
27  *
28  *  TBD: 1. Implement passive cooling hysteresis.
29  *       2. Enhance passive cooling (CPU) states/limit interface to support
30  *          concepts of 'multiple limiters', upper/lower limits, etc.
31  *
32  */
33 
34 #include <linux/kernel.h>
35 #include <linux/module.h>
36 #include <linux/dmi.h>
37 #include <linux/init.h>
38 #include <linux/slab.h>
39 #include <linux/types.h>
40 #include <linux/jiffies.h>
41 #include <linux/kmod.h>
42 #include <linux/reboot.h>
43 #include <linux/device.h>
44 #include <asm/uaccess.h>
45 #include <linux/thermal.h>
46 #include <acpi/acpi_bus.h>
47 #include <acpi/acpi_drivers.h>
48 
49 #define PREFIX "ACPI: "
50 
51 #define ACPI_THERMAL_CLASS		"thermal_zone"
52 #define ACPI_THERMAL_DEVICE_NAME	"Thermal Zone"
53 #define ACPI_THERMAL_FILE_STATE		"state"
54 #define ACPI_THERMAL_FILE_TEMPERATURE	"temperature"
55 #define ACPI_THERMAL_FILE_TRIP_POINTS	"trip_points"
56 #define ACPI_THERMAL_FILE_COOLING_MODE	"cooling_mode"
57 #define ACPI_THERMAL_FILE_POLLING_FREQ	"polling_frequency"
58 #define ACPI_THERMAL_NOTIFY_TEMPERATURE	0x80
59 #define ACPI_THERMAL_NOTIFY_THRESHOLDS	0x81
60 #define ACPI_THERMAL_NOTIFY_DEVICES	0x82
61 #define ACPI_THERMAL_NOTIFY_CRITICAL	0xF0
62 #define ACPI_THERMAL_NOTIFY_HOT		0xF1
63 #define ACPI_THERMAL_MODE_ACTIVE	0x00
64 
65 #define ACPI_THERMAL_MAX_ACTIVE	10
66 #define ACPI_THERMAL_MAX_LIMIT_STR_LEN 65
67 
68 #define _COMPONENT		ACPI_THERMAL_COMPONENT
69 ACPI_MODULE_NAME("thermal");
70 
71 MODULE_AUTHOR("Paul Diefenbaugh");
72 MODULE_DESCRIPTION("ACPI Thermal Zone Driver");
73 MODULE_LICENSE("GPL");
74 
75 static int act;
76 module_param(act, int, 0644);
77 MODULE_PARM_DESC(act, "Disable or override all lowest active trip points.");
78 
79 static int crt;
80 module_param(crt, int, 0644);
81 MODULE_PARM_DESC(crt, "Disable or lower all critical trip points.");
82 
83 static int tzp;
84 module_param(tzp, int, 0444);
85 MODULE_PARM_DESC(tzp, "Thermal zone polling frequency, in 1/10 seconds.");
86 
87 static int nocrt;
88 module_param(nocrt, int, 0);
89 MODULE_PARM_DESC(nocrt, "Set to take no action upon ACPI thermal zone critical trips points.");
90 
91 static int off;
92 module_param(off, int, 0);
93 MODULE_PARM_DESC(off, "Set to disable ACPI thermal support.");
94 
95 static int psv;
96 module_param(psv, int, 0644);
97 MODULE_PARM_DESC(psv, "Disable or override all passive trip points.");
98 
99 static int acpi_thermal_add(struct acpi_device *device);
100 static int acpi_thermal_remove(struct acpi_device *device, int type);
101 static void acpi_thermal_notify(struct acpi_device *device, u32 event);
102 
103 static const struct acpi_device_id  thermal_device_ids[] = {
104 	{ACPI_THERMAL_HID, 0},
105 	{"", 0},
106 };
107 MODULE_DEVICE_TABLE(acpi, thermal_device_ids);
108 
109 #ifdef CONFIG_PM_SLEEP
110 static int acpi_thermal_resume(struct device *dev);
111 #endif
112 static SIMPLE_DEV_PM_OPS(acpi_thermal_pm, NULL, acpi_thermal_resume);
113 
114 static struct acpi_driver acpi_thermal_driver = {
115 	.name = "thermal",
116 	.class = ACPI_THERMAL_CLASS,
117 	.ids = thermal_device_ids,
118 	.ops = {
119 		.add = acpi_thermal_add,
120 		.remove = acpi_thermal_remove,
121 		.notify = acpi_thermal_notify,
122 		},
123 	.drv.pm = &acpi_thermal_pm,
124 };
125 
126 struct acpi_thermal_state {
127 	u8 critical:1;
128 	u8 hot:1;
129 	u8 passive:1;
130 	u8 active:1;
131 	u8 reserved:4;
132 	int active_index;
133 };
134 
135 struct acpi_thermal_state_flags {
136 	u8 valid:1;
137 	u8 enabled:1;
138 	u8 reserved:6;
139 };
140 
141 struct acpi_thermal_critical {
142 	struct acpi_thermal_state_flags flags;
143 	unsigned long temperature;
144 };
145 
146 struct acpi_thermal_hot {
147 	struct acpi_thermal_state_flags flags;
148 	unsigned long temperature;
149 };
150 
151 struct acpi_thermal_passive {
152 	struct acpi_thermal_state_flags flags;
153 	unsigned long temperature;
154 	unsigned long tc1;
155 	unsigned long tc2;
156 	unsigned long tsp;
157 	struct acpi_handle_list devices;
158 };
159 
160 struct acpi_thermal_active {
161 	struct acpi_thermal_state_flags flags;
162 	unsigned long temperature;
163 	struct acpi_handle_list devices;
164 };
165 
166 struct acpi_thermal_trips {
167 	struct acpi_thermal_critical critical;
168 	struct acpi_thermal_hot hot;
169 	struct acpi_thermal_passive passive;
170 	struct acpi_thermal_active active[ACPI_THERMAL_MAX_ACTIVE];
171 };
172 
173 struct acpi_thermal_flags {
174 	u8 cooling_mode:1;	/* _SCP */
175 	u8 devices:1;		/* _TZD */
176 	u8 reserved:6;
177 };
178 
179 struct acpi_thermal {
180 	struct acpi_device * device;
181 	acpi_bus_id name;
182 	unsigned long temperature;
183 	unsigned long last_temperature;
184 	unsigned long polling_frequency;
185 	volatile u8 zombie;
186 	struct acpi_thermal_flags flags;
187 	struct acpi_thermal_state state;
188 	struct acpi_thermal_trips trips;
189 	struct acpi_handle_list devices;
190 	struct thermal_zone_device *thermal_zone;
191 	int tz_enabled;
192 	int kelvin_offset;
193 	struct mutex lock;
194 };
195 
196 /* --------------------------------------------------------------------------
197                              Thermal Zone Management
198    -------------------------------------------------------------------------- */
199 
200 static int acpi_thermal_get_temperature(struct acpi_thermal *tz)
201 {
202 	acpi_status status = AE_OK;
203 	unsigned long long tmp;
204 
205 	if (!tz)
206 		return -EINVAL;
207 
208 	tz->last_temperature = tz->temperature;
209 
210 	status = acpi_evaluate_integer(tz->device->handle, "_TMP", NULL, &tmp);
211 	if (ACPI_FAILURE(status))
212 		return -ENODEV;
213 
214 	tz->temperature = tmp;
215 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Temperature is %lu dK\n",
216 			  tz->temperature));
217 
218 	return 0;
219 }
220 
221 static int acpi_thermal_get_polling_frequency(struct acpi_thermal *tz)
222 {
223 	acpi_status status = AE_OK;
224 	unsigned long long tmp;
225 
226 	if (!tz)
227 		return -EINVAL;
228 
229 	status = acpi_evaluate_integer(tz->device->handle, "_TZP", NULL, &tmp);
230 	if (ACPI_FAILURE(status))
231 		return -ENODEV;
232 
233 	tz->polling_frequency = tmp;
234 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Polling frequency is %lu dS\n",
235 			  tz->polling_frequency));
236 
237 	return 0;
238 }
239 
240 static int acpi_thermal_set_cooling_mode(struct acpi_thermal *tz, int mode)
241 {
242 	acpi_status status = AE_OK;
243 	union acpi_object arg0 = { ACPI_TYPE_INTEGER };
244 	struct acpi_object_list arg_list = { 1, &arg0 };
245 	acpi_handle handle = NULL;
246 
247 
248 	if (!tz)
249 		return -EINVAL;
250 
251 	status = acpi_get_handle(tz->device->handle, "_SCP", &handle);
252 	if (ACPI_FAILURE(status)) {
253 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "_SCP not present\n"));
254 		return -ENODEV;
255 	}
256 
257 	arg0.integer.value = mode;
258 
259 	status = acpi_evaluate_object(handle, NULL, &arg_list, NULL);
260 	if (ACPI_FAILURE(status))
261 		return -ENODEV;
262 
263 	return 0;
264 }
265 
266 #define ACPI_TRIPS_CRITICAL	0x01
267 #define ACPI_TRIPS_HOT		0x02
268 #define ACPI_TRIPS_PASSIVE	0x04
269 #define ACPI_TRIPS_ACTIVE	0x08
270 #define ACPI_TRIPS_DEVICES	0x10
271 
272 #define ACPI_TRIPS_REFRESH_THRESHOLDS	(ACPI_TRIPS_PASSIVE | ACPI_TRIPS_ACTIVE)
273 #define ACPI_TRIPS_REFRESH_DEVICES	ACPI_TRIPS_DEVICES
274 
275 #define ACPI_TRIPS_INIT      (ACPI_TRIPS_CRITICAL | ACPI_TRIPS_HOT |	\
276 			      ACPI_TRIPS_PASSIVE | ACPI_TRIPS_ACTIVE |	\
277 			      ACPI_TRIPS_DEVICES)
278 
279 /*
280  * This exception is thrown out in two cases:
281  * 1.An invalid trip point becomes invalid or a valid trip point becomes invalid
282  *   when re-evaluating the AML code.
283  * 2.TODO: Devices listed in _PSL, _ALx, _TZD may change.
284  *   We need to re-bind the cooling devices of a thermal zone when this occurs.
285  */
286 #define ACPI_THERMAL_TRIPS_EXCEPTION(flags, str)	\
287 do {	\
288 	if (flags != ACPI_TRIPS_INIT)	\
289 		ACPI_EXCEPTION((AE_INFO, AE_ERROR,	\
290 		"ACPI thermal trip point %s changed\n"	\
291 		"Please send acpidump to linux-acpi@vger.kernel.org\n", str)); \
292 } while (0)
293 
294 static int acpi_thermal_trips_update(struct acpi_thermal *tz, int flag)
295 {
296 	acpi_status status = AE_OK;
297 	unsigned long long tmp;
298 	struct acpi_handle_list devices;
299 	int valid = 0;
300 	int i;
301 
302 	/* Critical Shutdown */
303 	if (flag & ACPI_TRIPS_CRITICAL) {
304 		status = acpi_evaluate_integer(tz->device->handle,
305 				"_CRT", NULL, &tmp);
306 		tz->trips.critical.temperature = tmp;
307 		/*
308 		 * Treat freezing temperatures as invalid as well; some
309 		 * BIOSes return really low values and cause reboots at startup.
310 		 * Below zero (Celsius) values clearly aren't right for sure..
311 		 * ... so lets discard those as invalid.
312 		 */
313 		if (ACPI_FAILURE(status)) {
314 			tz->trips.critical.flags.valid = 0;
315 			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
316 					  "No critical threshold\n"));
317 		} else if (tmp <= 2732) {
318 			printk(KERN_WARNING FW_BUG "Invalid critical threshold "
319 			       "(%llu)\n", tmp);
320 			tz->trips.critical.flags.valid = 0;
321 		} else {
322 			tz->trips.critical.flags.valid = 1;
323 			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
324 					  "Found critical threshold [%lu]\n",
325 					  tz->trips.critical.temperature));
326 		}
327 		if (tz->trips.critical.flags.valid == 1) {
328 			if (crt == -1) {
329 				tz->trips.critical.flags.valid = 0;
330 			} else if (crt > 0) {
331 				unsigned long crt_k = CELSIUS_TO_KELVIN(crt);
332 				/*
333 				 * Allow override critical threshold
334 				 */
335 				if (crt_k > tz->trips.critical.temperature)
336 					printk(KERN_WARNING PREFIX
337 						"Critical threshold %d C\n", crt);
338 				tz->trips.critical.temperature = crt_k;
339 			}
340 		}
341 	}
342 
343 	/* Critical Sleep (optional) */
344 	if (flag & ACPI_TRIPS_HOT) {
345 		status = acpi_evaluate_integer(tz->device->handle,
346 				"_HOT", NULL, &tmp);
347 		if (ACPI_FAILURE(status)) {
348 			tz->trips.hot.flags.valid = 0;
349 			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
350 					"No hot threshold\n"));
351 		} else {
352 			tz->trips.hot.temperature = tmp;
353 			tz->trips.hot.flags.valid = 1;
354 			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
355 					"Found hot threshold [%lu]\n",
356 					tz->trips.critical.temperature));
357 		}
358 	}
359 
360 	/* Passive (optional) */
361 	if (((flag & ACPI_TRIPS_PASSIVE) && tz->trips.passive.flags.valid) ||
362 		(flag == ACPI_TRIPS_INIT)) {
363 		valid = tz->trips.passive.flags.valid;
364 		if (psv == -1) {
365 			status = AE_SUPPORT;
366 		} else if (psv > 0) {
367 			tmp = CELSIUS_TO_KELVIN(psv);
368 			status = AE_OK;
369 		} else {
370 			status = acpi_evaluate_integer(tz->device->handle,
371 				"_PSV", NULL, &tmp);
372 		}
373 
374 		if (ACPI_FAILURE(status))
375 			tz->trips.passive.flags.valid = 0;
376 		else {
377 			tz->trips.passive.temperature = tmp;
378 			tz->trips.passive.flags.valid = 1;
379 			if (flag == ACPI_TRIPS_INIT) {
380 				status = acpi_evaluate_integer(
381 						tz->device->handle, "_TC1",
382 						NULL, &tmp);
383 				if (ACPI_FAILURE(status))
384 					tz->trips.passive.flags.valid = 0;
385 				else
386 					tz->trips.passive.tc1 = tmp;
387 				status = acpi_evaluate_integer(
388 						tz->device->handle, "_TC2",
389 						NULL, &tmp);
390 				if (ACPI_FAILURE(status))
391 					tz->trips.passive.flags.valid = 0;
392 				else
393 					tz->trips.passive.tc2 = tmp;
394 				status = acpi_evaluate_integer(
395 						tz->device->handle, "_TSP",
396 						NULL, &tmp);
397 				if (ACPI_FAILURE(status))
398 					tz->trips.passive.flags.valid = 0;
399 				else
400 					tz->trips.passive.tsp = tmp;
401 			}
402 		}
403 	}
404 	if ((flag & ACPI_TRIPS_DEVICES) && tz->trips.passive.flags.valid) {
405 		memset(&devices, 0, sizeof(struct acpi_handle_list));
406 		status = acpi_evaluate_reference(tz->device->handle, "_PSL",
407 							NULL, &devices);
408 		if (ACPI_FAILURE(status)) {
409 			printk(KERN_WARNING PREFIX
410 				"Invalid passive threshold\n");
411 			tz->trips.passive.flags.valid = 0;
412 		}
413 		else
414 			tz->trips.passive.flags.valid = 1;
415 
416 		if (memcmp(&tz->trips.passive.devices, &devices,
417 				sizeof(struct acpi_handle_list))) {
418 			memcpy(&tz->trips.passive.devices, &devices,
419 				sizeof(struct acpi_handle_list));
420 			ACPI_THERMAL_TRIPS_EXCEPTION(flag, "device");
421 		}
422 	}
423 	if ((flag & ACPI_TRIPS_PASSIVE) || (flag & ACPI_TRIPS_DEVICES)) {
424 		if (valid != tz->trips.passive.flags.valid)
425 				ACPI_THERMAL_TRIPS_EXCEPTION(flag, "state");
426 	}
427 
428 	/* Active (optional) */
429 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
430 		char name[5] = { '_', 'A', 'C', ('0' + i), '\0' };
431 		valid = tz->trips.active[i].flags.valid;
432 
433 		if (act == -1)
434 			break; /* disable all active trip points */
435 
436 		if ((flag == ACPI_TRIPS_INIT) || ((flag & ACPI_TRIPS_ACTIVE) &&
437 			tz->trips.active[i].flags.valid)) {
438 			status = acpi_evaluate_integer(tz->device->handle,
439 							name, NULL, &tmp);
440 			if (ACPI_FAILURE(status)) {
441 				tz->trips.active[i].flags.valid = 0;
442 				if (i == 0)
443 					break;
444 				if (act <= 0)
445 					break;
446 				if (i == 1)
447 					tz->trips.active[0].temperature =
448 						CELSIUS_TO_KELVIN(act);
449 				else
450 					/*
451 					 * Don't allow override higher than
452 					 * the next higher trip point
453 					 */
454 					tz->trips.active[i - 1].temperature =
455 						(tz->trips.active[i - 2].temperature <
456 						CELSIUS_TO_KELVIN(act) ?
457 						tz->trips.active[i - 2].temperature :
458 						CELSIUS_TO_KELVIN(act));
459 				break;
460 			} else {
461 				tz->trips.active[i].temperature = tmp;
462 				tz->trips.active[i].flags.valid = 1;
463 			}
464 		}
465 
466 		name[2] = 'L';
467 		if ((flag & ACPI_TRIPS_DEVICES) && tz->trips.active[i].flags.valid ) {
468 			memset(&devices, 0, sizeof(struct acpi_handle_list));
469 			status = acpi_evaluate_reference(tz->device->handle,
470 						name, NULL, &devices);
471 			if (ACPI_FAILURE(status)) {
472 				printk(KERN_WARNING PREFIX
473 					"Invalid active%d threshold\n", i);
474 				tz->trips.active[i].flags.valid = 0;
475 			}
476 			else
477 				tz->trips.active[i].flags.valid = 1;
478 
479 			if (memcmp(&tz->trips.active[i].devices, &devices,
480 					sizeof(struct acpi_handle_list))) {
481 				memcpy(&tz->trips.active[i].devices, &devices,
482 					sizeof(struct acpi_handle_list));
483 				ACPI_THERMAL_TRIPS_EXCEPTION(flag, "device");
484 			}
485 		}
486 		if ((flag & ACPI_TRIPS_ACTIVE) || (flag & ACPI_TRIPS_DEVICES))
487 			if (valid != tz->trips.active[i].flags.valid)
488 				ACPI_THERMAL_TRIPS_EXCEPTION(flag, "state");
489 
490 		if (!tz->trips.active[i].flags.valid)
491 			break;
492 	}
493 
494 	if (flag & ACPI_TRIPS_DEVICES) {
495 		memset(&devices, 0, sizeof(struct acpi_handle_list));
496 		status = acpi_evaluate_reference(tz->device->handle, "_TZD",
497 						NULL, &devices);
498 		if (memcmp(&tz->devices, &devices,
499 				sizeof(struct acpi_handle_list))) {
500 			memcpy(&tz->devices, &devices,
501 				sizeof(struct acpi_handle_list));
502 			ACPI_THERMAL_TRIPS_EXCEPTION(flag, "device");
503 		}
504 	}
505 
506 	return 0;
507 }
508 
509 static int acpi_thermal_get_trip_points(struct acpi_thermal *tz)
510 {
511 	int i, valid, ret = acpi_thermal_trips_update(tz, ACPI_TRIPS_INIT);
512 
513 	if (ret)
514 		return ret;
515 
516 	valid = tz->trips.critical.flags.valid |
517 		tz->trips.hot.flags.valid |
518 		tz->trips.passive.flags.valid;
519 
520 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++)
521 		valid |= tz->trips.active[i].flags.valid;
522 
523 	if (!valid) {
524 		printk(KERN_WARNING FW_BUG "No valid trip found\n");
525 		return -ENODEV;
526 	}
527 	return 0;
528 }
529 
530 static void acpi_thermal_check(void *data)
531 {
532 	struct acpi_thermal *tz = data;
533 
534 	thermal_zone_device_update(tz->thermal_zone);
535 }
536 
537 /* sys I/F for generic thermal sysfs support */
538 #define KELVIN_TO_MILLICELSIUS(t, off) (((t) - (off)) * 100)
539 
540 static int thermal_get_temp(struct thermal_zone_device *thermal,
541 			    unsigned long *temp)
542 {
543 	struct acpi_thermal *tz = thermal->devdata;
544 	int result;
545 
546 	if (!tz)
547 		return -EINVAL;
548 
549 	result = acpi_thermal_get_temperature(tz);
550 	if (result)
551 		return result;
552 
553 	*temp = KELVIN_TO_MILLICELSIUS(tz->temperature, tz->kelvin_offset);
554 	return 0;
555 }
556 
557 static int thermal_get_mode(struct thermal_zone_device *thermal,
558 				enum thermal_device_mode *mode)
559 {
560 	struct acpi_thermal *tz = thermal->devdata;
561 
562 	if (!tz)
563 		return -EINVAL;
564 
565 	*mode = tz->tz_enabled ? THERMAL_DEVICE_ENABLED :
566 		THERMAL_DEVICE_DISABLED;
567 
568 	return 0;
569 }
570 
571 static int thermal_set_mode(struct thermal_zone_device *thermal,
572 				enum thermal_device_mode mode)
573 {
574 	struct acpi_thermal *tz = thermal->devdata;
575 	int enable;
576 
577 	if (!tz)
578 		return -EINVAL;
579 
580 	/*
581 	 * enable/disable thermal management from ACPI thermal driver
582 	 */
583 	if (mode == THERMAL_DEVICE_ENABLED)
584 		enable = 1;
585 	else if (mode == THERMAL_DEVICE_DISABLED)
586 		enable = 0;
587 	else
588 		return -EINVAL;
589 
590 	if (enable != tz->tz_enabled) {
591 		tz->tz_enabled = enable;
592 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
593 			"%s kernel ACPI thermal control\n",
594 			tz->tz_enabled ? "Enable" : "Disable"));
595 		acpi_thermal_check(tz);
596 	}
597 	return 0;
598 }
599 
600 static int thermal_get_trip_type(struct thermal_zone_device *thermal,
601 				 int trip, enum thermal_trip_type *type)
602 {
603 	struct acpi_thermal *tz = thermal->devdata;
604 	int i;
605 
606 	if (!tz || trip < 0)
607 		return -EINVAL;
608 
609 	if (tz->trips.critical.flags.valid) {
610 		if (!trip) {
611 			*type = THERMAL_TRIP_CRITICAL;
612 			return 0;
613 		}
614 		trip--;
615 	}
616 
617 	if (tz->trips.hot.flags.valid) {
618 		if (!trip) {
619 			*type = THERMAL_TRIP_HOT;
620 			return 0;
621 		}
622 		trip--;
623 	}
624 
625 	if (tz->trips.passive.flags.valid) {
626 		if (!trip) {
627 			*type = THERMAL_TRIP_PASSIVE;
628 			return 0;
629 		}
630 		trip--;
631 	}
632 
633 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE &&
634 		tz->trips.active[i].flags.valid; i++) {
635 		if (!trip) {
636 			*type = THERMAL_TRIP_ACTIVE;
637 			return 0;
638 		}
639 		trip--;
640 	}
641 
642 	return -EINVAL;
643 }
644 
645 static int thermal_get_trip_temp(struct thermal_zone_device *thermal,
646 				 int trip, unsigned long *temp)
647 {
648 	struct acpi_thermal *tz = thermal->devdata;
649 	int i;
650 
651 	if (!tz || trip < 0)
652 		return -EINVAL;
653 
654 	if (tz->trips.critical.flags.valid) {
655 		if (!trip) {
656 			*temp = KELVIN_TO_MILLICELSIUS(
657 				tz->trips.critical.temperature,
658 				tz->kelvin_offset);
659 			return 0;
660 		}
661 		trip--;
662 	}
663 
664 	if (tz->trips.hot.flags.valid) {
665 		if (!trip) {
666 			*temp = KELVIN_TO_MILLICELSIUS(
667 				tz->trips.hot.temperature,
668 				tz->kelvin_offset);
669 			return 0;
670 		}
671 		trip--;
672 	}
673 
674 	if (tz->trips.passive.flags.valid) {
675 		if (!trip) {
676 			*temp = KELVIN_TO_MILLICELSIUS(
677 				tz->trips.passive.temperature,
678 				tz->kelvin_offset);
679 			return 0;
680 		}
681 		trip--;
682 	}
683 
684 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE &&
685 		tz->trips.active[i].flags.valid; i++) {
686 		if (!trip) {
687 			*temp = KELVIN_TO_MILLICELSIUS(
688 				tz->trips.active[i].temperature,
689 				tz->kelvin_offset);
690 			return 0;
691 		}
692 		trip--;
693 	}
694 
695 	return -EINVAL;
696 }
697 
698 static int thermal_get_crit_temp(struct thermal_zone_device *thermal,
699 				unsigned long *temperature) {
700 	struct acpi_thermal *tz = thermal->devdata;
701 
702 	if (tz->trips.critical.flags.valid) {
703 		*temperature = KELVIN_TO_MILLICELSIUS(
704 				tz->trips.critical.temperature,
705 				tz->kelvin_offset);
706 		return 0;
707 	} else
708 		return -EINVAL;
709 }
710 
711 static int thermal_get_trend(struct thermal_zone_device *thermal,
712 				int trip, enum thermal_trend *trend)
713 {
714 	struct acpi_thermal *tz = thermal->devdata;
715 	enum thermal_trip_type type;
716 	int i;
717 
718 	if (thermal_get_trip_type(thermal, trip, &type))
719 		return -EINVAL;
720 
721 	if (type == THERMAL_TRIP_ACTIVE) {
722 		/* aggressive active cooling */
723 		*trend = THERMAL_TREND_RAISING;
724 		return 0;
725 	}
726 
727 	/*
728 	 * tz->temperature has already been updated by generic thermal layer,
729 	 * before this callback being invoked
730 	 */
731 	i = (tz->trips.passive.tc1 * (tz->temperature - tz->last_temperature))
732 		+ (tz->trips.passive.tc2
733 		* (tz->temperature - tz->trips.passive.temperature));
734 
735 	if (i > 0)
736 		*trend = THERMAL_TREND_RAISING;
737 	else if (i < 0)
738 		*trend = THERMAL_TREND_DROPPING;
739 	else
740 		*trend = THERMAL_TREND_STABLE;
741 	return 0;
742 }
743 
744 
745 static int thermal_notify(struct thermal_zone_device *thermal, int trip,
746 			   enum thermal_trip_type trip_type)
747 {
748 	u8 type = 0;
749 	struct acpi_thermal *tz = thermal->devdata;
750 
751 	if (trip_type == THERMAL_TRIP_CRITICAL)
752 		type = ACPI_THERMAL_NOTIFY_CRITICAL;
753 	else if (trip_type == THERMAL_TRIP_HOT)
754 		type = ACPI_THERMAL_NOTIFY_HOT;
755 	else
756 		return 0;
757 
758 	acpi_bus_generate_proc_event(tz->device, type, 1);
759 	acpi_bus_generate_netlink_event(tz->device->pnp.device_class,
760 					dev_name(&tz->device->dev), type, 1);
761 
762 	if (trip_type == THERMAL_TRIP_CRITICAL && nocrt)
763 		return 1;
764 
765 	return 0;
766 }
767 
768 static int acpi_thermal_cooling_device_cb(struct thermal_zone_device *thermal,
769 					struct thermal_cooling_device *cdev,
770 					bool bind)
771 {
772 	struct acpi_device *device = cdev->devdata;
773 	struct acpi_thermal *tz = thermal->devdata;
774 	struct acpi_device *dev;
775 	acpi_status status;
776 	acpi_handle handle;
777 	int i;
778 	int j;
779 	int trip = -1;
780 	int result = 0;
781 
782 	if (tz->trips.critical.flags.valid)
783 		trip++;
784 
785 	if (tz->trips.hot.flags.valid)
786 		trip++;
787 
788 	if (tz->trips.passive.flags.valid) {
789 		trip++;
790 		for (i = 0; i < tz->trips.passive.devices.count;
791 		    i++) {
792 			handle = tz->trips.passive.devices.handles[i];
793 			status = acpi_bus_get_device(handle, &dev);
794 			if (ACPI_FAILURE(status) || dev != device)
795 				continue;
796 			if (bind)
797 				result =
798 					thermal_zone_bind_cooling_device
799 					(thermal, trip, cdev,
800 					 THERMAL_NO_LIMIT, THERMAL_NO_LIMIT);
801 			else
802 				result =
803 					thermal_zone_unbind_cooling_device
804 					(thermal, trip, cdev);
805 			if (result)
806 				goto failed;
807 		}
808 	}
809 
810 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
811 		if (!tz->trips.active[i].flags.valid)
812 			break;
813 		trip++;
814 		for (j = 0;
815 		    j < tz->trips.active[i].devices.count;
816 		    j++) {
817 			handle = tz->trips.active[i].devices.handles[j];
818 			status = acpi_bus_get_device(handle, &dev);
819 			if (ACPI_FAILURE(status) || dev != device)
820 				continue;
821 			if (bind)
822 				result = thermal_zone_bind_cooling_device
823 					(thermal, trip, cdev,
824 					 THERMAL_NO_LIMIT, THERMAL_NO_LIMIT);
825 			else
826 				result = thermal_zone_unbind_cooling_device
827 					(thermal, trip, cdev);
828 			if (result)
829 				goto failed;
830 		}
831 	}
832 
833 	for (i = 0; i < tz->devices.count; i++) {
834 		handle = tz->devices.handles[i];
835 		status = acpi_bus_get_device(handle, &dev);
836 		if (ACPI_SUCCESS(status) && (dev == device)) {
837 			if (bind)
838 				result = thermal_zone_bind_cooling_device
839 						(thermal, -1, cdev,
840 						 THERMAL_NO_LIMIT,
841 						 THERMAL_NO_LIMIT);
842 			else
843 				result = thermal_zone_unbind_cooling_device
844 						(thermal, -1, cdev);
845 			if (result)
846 				goto failed;
847 		}
848 	}
849 
850 failed:
851 	return result;
852 }
853 
854 static int
855 acpi_thermal_bind_cooling_device(struct thermal_zone_device *thermal,
856 					struct thermal_cooling_device *cdev)
857 {
858 	return acpi_thermal_cooling_device_cb(thermal, cdev, true);
859 }
860 
861 static int
862 acpi_thermal_unbind_cooling_device(struct thermal_zone_device *thermal,
863 					struct thermal_cooling_device *cdev)
864 {
865 	return acpi_thermal_cooling_device_cb(thermal, cdev, false);
866 }
867 
868 static const struct thermal_zone_device_ops acpi_thermal_zone_ops = {
869 	.bind = acpi_thermal_bind_cooling_device,
870 	.unbind	= acpi_thermal_unbind_cooling_device,
871 	.get_temp = thermal_get_temp,
872 	.get_mode = thermal_get_mode,
873 	.set_mode = thermal_set_mode,
874 	.get_trip_type = thermal_get_trip_type,
875 	.get_trip_temp = thermal_get_trip_temp,
876 	.get_crit_temp = thermal_get_crit_temp,
877 	.get_trend = thermal_get_trend,
878 	.notify = thermal_notify,
879 };
880 
881 static int acpi_thermal_register_thermal_zone(struct acpi_thermal *tz)
882 {
883 	int trips = 0;
884 	int result;
885 	acpi_status status;
886 	int i;
887 
888 	if (tz->trips.critical.flags.valid)
889 		trips++;
890 
891 	if (tz->trips.hot.flags.valid)
892 		trips++;
893 
894 	if (tz->trips.passive.flags.valid)
895 		trips++;
896 
897 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE &&
898 			tz->trips.active[i].flags.valid; i++, trips++);
899 
900 	if (tz->trips.passive.flags.valid)
901 		tz->thermal_zone =
902 			thermal_zone_device_register("acpitz", trips, 0, tz,
903 						&acpi_thermal_zone_ops, NULL,
904 						     tz->trips.passive.tsp*100,
905 						     tz->polling_frequency*100);
906 	else
907 		tz->thermal_zone =
908 			thermal_zone_device_register("acpitz", trips, 0, tz,
909 						&acpi_thermal_zone_ops, NULL,
910 						0, tz->polling_frequency*100);
911 	if (IS_ERR(tz->thermal_zone))
912 		return -ENODEV;
913 
914 	result = sysfs_create_link(&tz->device->dev.kobj,
915 				   &tz->thermal_zone->device.kobj, "thermal_zone");
916 	if (result)
917 		return result;
918 
919 	result = sysfs_create_link(&tz->thermal_zone->device.kobj,
920 				   &tz->device->dev.kobj, "device");
921 	if (result)
922 		return result;
923 
924 	status = acpi_attach_data(tz->device->handle,
925 				  acpi_bus_private_data_handler,
926 				  tz->thermal_zone);
927 	if (ACPI_FAILURE(status)) {
928 		printk(KERN_ERR PREFIX
929 				"Error attaching device data\n");
930 		return -ENODEV;
931 	}
932 
933 	tz->tz_enabled = 1;
934 
935 	dev_info(&tz->device->dev, "registered as thermal_zone%d\n",
936 		 tz->thermal_zone->id);
937 	return 0;
938 }
939 
940 static void acpi_thermal_unregister_thermal_zone(struct acpi_thermal *tz)
941 {
942 	sysfs_remove_link(&tz->device->dev.kobj, "thermal_zone");
943 	sysfs_remove_link(&tz->thermal_zone->device.kobj, "device");
944 	thermal_zone_device_unregister(tz->thermal_zone);
945 	tz->thermal_zone = NULL;
946 	acpi_detach_data(tz->device->handle, acpi_bus_private_data_handler);
947 }
948 
949 
950 /* --------------------------------------------------------------------------
951                                  Driver Interface
952    -------------------------------------------------------------------------- */
953 
954 static void acpi_thermal_notify(struct acpi_device *device, u32 event)
955 {
956 	struct acpi_thermal *tz = acpi_driver_data(device);
957 
958 
959 	if (!tz)
960 		return;
961 
962 	switch (event) {
963 	case ACPI_THERMAL_NOTIFY_TEMPERATURE:
964 		acpi_thermal_check(tz);
965 		break;
966 	case ACPI_THERMAL_NOTIFY_THRESHOLDS:
967 		acpi_thermal_trips_update(tz, ACPI_TRIPS_REFRESH_THRESHOLDS);
968 		acpi_thermal_check(tz);
969 		acpi_bus_generate_proc_event(device, event, 0);
970 		acpi_bus_generate_netlink_event(device->pnp.device_class,
971 						  dev_name(&device->dev), event, 0);
972 		break;
973 	case ACPI_THERMAL_NOTIFY_DEVICES:
974 		acpi_thermal_trips_update(tz, ACPI_TRIPS_REFRESH_DEVICES);
975 		acpi_thermal_check(tz);
976 		acpi_bus_generate_proc_event(device, event, 0);
977 		acpi_bus_generate_netlink_event(device->pnp.device_class,
978 						  dev_name(&device->dev), event, 0);
979 		break;
980 	default:
981 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
982 				  "Unsupported event [0x%x]\n", event));
983 		break;
984 	}
985 }
986 
987 /*
988  * On some platforms, the AML code has dependency about
989  * the evaluating order of _TMP and _CRT/_HOT/_PSV/_ACx.
990  * 1. On HP Pavilion G4-1016tx, _TMP must be invoked after
991  *    /_CRT/_HOT/_PSV/_ACx, or else system will be power off.
992  * 2. On HP Compaq 6715b/6715s, the return value of _PSV is 0
993  *    if _TMP has never been evaluated.
994  *
995  * As this dependency is totally transparent to OS, evaluate
996  * all of them once, in the order of _CRT/_HOT/_PSV/_ACx,
997  * _TMP, before they are actually used.
998  */
999 static void acpi_thermal_aml_dependency_fix(struct acpi_thermal *tz)
1000 {
1001 	acpi_handle handle = tz->device->handle;
1002 	unsigned long long value;
1003 	int i;
1004 
1005 	acpi_evaluate_integer(handle, "_CRT", NULL, &value);
1006 	acpi_evaluate_integer(handle, "_HOT", NULL, &value);
1007 	acpi_evaluate_integer(handle, "_PSV", NULL, &value);
1008 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
1009 		char name[5] = { '_', 'A', 'C', ('0' + i), '\0' };
1010 		acpi_status status;
1011 
1012 		status = acpi_evaluate_integer(handle, name, NULL, &value);
1013 		if (status == AE_NOT_FOUND)
1014 			break;
1015 	}
1016 	acpi_evaluate_integer(handle, "_TMP", NULL, &value);
1017 }
1018 
1019 static int acpi_thermal_get_info(struct acpi_thermal *tz)
1020 {
1021 	int result = 0;
1022 
1023 
1024 	if (!tz)
1025 		return -EINVAL;
1026 
1027 	acpi_thermal_aml_dependency_fix(tz);
1028 
1029 	/* Get trip points [_CRT, _PSV, etc.] (required) */
1030 	result = acpi_thermal_get_trip_points(tz);
1031 	if (result)
1032 		return result;
1033 
1034 	/* Get temperature [_TMP] (required) */
1035 	result = acpi_thermal_get_temperature(tz);
1036 	if (result)
1037 		return result;
1038 
1039 	/* Set the cooling mode [_SCP] to active cooling (default) */
1040 	result = acpi_thermal_set_cooling_mode(tz, ACPI_THERMAL_MODE_ACTIVE);
1041 	if (!result)
1042 		tz->flags.cooling_mode = 1;
1043 
1044 	/* Get default polling frequency [_TZP] (optional) */
1045 	if (tzp)
1046 		tz->polling_frequency = tzp;
1047 	else
1048 		acpi_thermal_get_polling_frequency(tz);
1049 
1050 	return 0;
1051 }
1052 
1053 /*
1054  * The exact offset between Kelvin and degree Celsius is 273.15. However ACPI
1055  * handles temperature values with a single decimal place. As a consequence,
1056  * some implementations use an offset of 273.1 and others use an offset of
1057  * 273.2. Try to find out which one is being used, to present the most
1058  * accurate and visually appealing number.
1059  *
1060  * The heuristic below should work for all ACPI thermal zones which have a
1061  * critical trip point with a value being a multiple of 0.5 degree Celsius.
1062  */
1063 static void acpi_thermal_guess_offset(struct acpi_thermal *tz)
1064 {
1065 	if (tz->trips.critical.flags.valid &&
1066 	    (tz->trips.critical.temperature % 5) == 1)
1067 		tz->kelvin_offset = 2731;
1068 	else
1069 		tz->kelvin_offset = 2732;
1070 }
1071 
1072 static int acpi_thermal_add(struct acpi_device *device)
1073 {
1074 	int result = 0;
1075 	struct acpi_thermal *tz = NULL;
1076 
1077 
1078 	if (!device)
1079 		return -EINVAL;
1080 
1081 	tz = kzalloc(sizeof(struct acpi_thermal), GFP_KERNEL);
1082 	if (!tz)
1083 		return -ENOMEM;
1084 
1085 	tz->device = device;
1086 	strcpy(tz->name, device->pnp.bus_id);
1087 	strcpy(acpi_device_name(device), ACPI_THERMAL_DEVICE_NAME);
1088 	strcpy(acpi_device_class(device), ACPI_THERMAL_CLASS);
1089 	device->driver_data = tz;
1090 	mutex_init(&tz->lock);
1091 
1092 
1093 	result = acpi_thermal_get_info(tz);
1094 	if (result)
1095 		goto free_memory;
1096 
1097 	acpi_thermal_guess_offset(tz);
1098 
1099 	result = acpi_thermal_register_thermal_zone(tz);
1100 	if (result)
1101 		goto free_memory;
1102 
1103 	printk(KERN_INFO PREFIX "%s [%s] (%ld C)\n",
1104 	       acpi_device_name(device), acpi_device_bid(device),
1105 	       KELVIN_TO_CELSIUS(tz->temperature));
1106 	goto end;
1107 
1108 free_memory:
1109 	kfree(tz);
1110 end:
1111 	return result;
1112 }
1113 
1114 static int acpi_thermal_remove(struct acpi_device *device, int type)
1115 {
1116 	struct acpi_thermal *tz = NULL;
1117 
1118 	if (!device || !acpi_driver_data(device))
1119 		return -EINVAL;
1120 
1121 	tz = acpi_driver_data(device);
1122 
1123 	acpi_thermal_unregister_thermal_zone(tz);
1124 	mutex_destroy(&tz->lock);
1125 	kfree(tz);
1126 	return 0;
1127 }
1128 
1129 #ifdef CONFIG_PM_SLEEP
1130 static int acpi_thermal_resume(struct device *dev)
1131 {
1132 	struct acpi_thermal *tz;
1133 	int i, j, power_state, result;
1134 
1135 	if (!dev)
1136 		return -EINVAL;
1137 
1138 	tz = acpi_driver_data(to_acpi_device(dev));
1139 	if (!tz)
1140 		return -EINVAL;
1141 
1142 	for (i = 0; i < ACPI_THERMAL_MAX_ACTIVE; i++) {
1143 		if (!(&tz->trips.active[i]))
1144 			break;
1145 		if (!tz->trips.active[i].flags.valid)
1146 			break;
1147 		tz->trips.active[i].flags.enabled = 1;
1148 		for (j = 0; j < tz->trips.active[i].devices.count; j++) {
1149 			result = acpi_bus_update_power(
1150 					tz->trips.active[i].devices.handles[j],
1151 					&power_state);
1152 			if (result || (power_state != ACPI_STATE_D0)) {
1153 				tz->trips.active[i].flags.enabled = 0;
1154 				break;
1155 			}
1156 		}
1157 		tz->state.active |= tz->trips.active[i].flags.enabled;
1158 	}
1159 
1160 	acpi_thermal_check(tz);
1161 
1162 	return AE_OK;
1163 }
1164 #endif
1165 
1166 static int thermal_act(const struct dmi_system_id *d) {
1167 
1168 	if (act == 0) {
1169 		printk(KERN_NOTICE "ACPI: %s detected: "
1170 			"disabling all active thermal trip points\n", d->ident);
1171 		act = -1;
1172 	}
1173 	return 0;
1174 }
1175 static int thermal_nocrt(const struct dmi_system_id *d) {
1176 
1177 	printk(KERN_NOTICE "ACPI: %s detected: "
1178 		"disabling all critical thermal trip point actions.\n", d->ident);
1179 	nocrt = 1;
1180 	return 0;
1181 }
1182 static int thermal_tzp(const struct dmi_system_id *d) {
1183 
1184 	if (tzp == 0) {
1185 		printk(KERN_NOTICE "ACPI: %s detected: "
1186 			"enabling thermal zone polling\n", d->ident);
1187 		tzp = 300;	/* 300 dS = 30 Seconds */
1188 	}
1189 	return 0;
1190 }
1191 static int thermal_psv(const struct dmi_system_id *d) {
1192 
1193 	if (psv == 0) {
1194 		printk(KERN_NOTICE "ACPI: %s detected: "
1195 			"disabling all passive thermal trip points\n", d->ident);
1196 		psv = -1;
1197 	}
1198 	return 0;
1199 }
1200 
1201 static struct dmi_system_id thermal_dmi_table[] __initdata = {
1202 	/*
1203 	 * Award BIOS on this AOpen makes thermal control almost worthless.
1204 	 * http://bugzilla.kernel.org/show_bug.cgi?id=8842
1205 	 */
1206 	{
1207 	 .callback = thermal_act,
1208 	 .ident = "AOpen i915GMm-HFS",
1209 	 .matches = {
1210 		DMI_MATCH(DMI_BOARD_VENDOR, "AOpen"),
1211 		DMI_MATCH(DMI_BOARD_NAME, "i915GMm-HFS"),
1212 		},
1213 	},
1214 	{
1215 	 .callback = thermal_psv,
1216 	 .ident = "AOpen i915GMm-HFS",
1217 	 .matches = {
1218 		DMI_MATCH(DMI_BOARD_VENDOR, "AOpen"),
1219 		DMI_MATCH(DMI_BOARD_NAME, "i915GMm-HFS"),
1220 		},
1221 	},
1222 	{
1223 	 .callback = thermal_tzp,
1224 	 .ident = "AOpen i915GMm-HFS",
1225 	 .matches = {
1226 		DMI_MATCH(DMI_BOARD_VENDOR, "AOpen"),
1227 		DMI_MATCH(DMI_BOARD_NAME, "i915GMm-HFS"),
1228 		},
1229 	},
1230 	{
1231 	 .callback = thermal_nocrt,
1232 	 .ident = "Gigabyte GA-7ZX",
1233 	 .matches = {
1234 		DMI_MATCH(DMI_BOARD_VENDOR, "Gigabyte Technology Co., Ltd."),
1235 		DMI_MATCH(DMI_BOARD_NAME, "7ZX"),
1236 		},
1237 	},
1238 	{}
1239 };
1240 
1241 static int __init acpi_thermal_init(void)
1242 {
1243 	int result = 0;
1244 
1245 	dmi_check_system(thermal_dmi_table);
1246 
1247 	if (off) {
1248 		printk(KERN_NOTICE "ACPI: thermal control disabled\n");
1249 		return -ENODEV;
1250 	}
1251 
1252 	result = acpi_bus_register_driver(&acpi_thermal_driver);
1253 	if (result < 0)
1254 		return -ENODEV;
1255 
1256 	return 0;
1257 }
1258 
1259 static void __exit acpi_thermal_exit(void)
1260 {
1261 
1262 	acpi_bus_unregister_driver(&acpi_thermal_driver);
1263 
1264 	return;
1265 }
1266 
1267 module_init(acpi_thermal_init);
1268 module_exit(acpi_thermal_exit);
1269