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