xref: /kernel/linux/linux-6.6/drivers/acpi/thermal.c (revision 62306a36)
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) \
66do { \
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
73static int act;
74module_param(act, int, 0644);
75MODULE_PARM_DESC(act, "Disable or override all lowest active trip points.");
76
77static int crt;
78module_param(crt, int, 0644);
79MODULE_PARM_DESC(crt, "Disable or lower all critical trip points.");
80
81static int tzp;
82module_param(tzp, int, 0444);
83MODULE_PARM_DESC(tzp, "Thermal zone polling frequency, in 1/10 seconds.");
84
85static int off;
86module_param(off, int, 0);
87MODULE_PARM_DESC(off, "Set to disable ACPI thermal support.");
88
89static int psv;
90module_param(psv, int, 0644);
91MODULE_PARM_DESC(psv, "Disable or override all passive trip points.");
92
93static struct workqueue_struct *acpi_thermal_pm_queue;
94
95struct acpi_thermal_trip {
96	unsigned long temperature;
97	bool valid;
98};
99
100struct 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
108struct acpi_thermal_active {
109	struct acpi_thermal_trip trip;
110	struct acpi_handle_list devices;
111};
112
113struct 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
120struct 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
141static 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
163static 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
182static 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
191static 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
402static 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
418static 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
430static 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
436static 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
454static 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
477static 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
494static 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
540static 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
549static 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
560static 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
629failed:
630	return result;
631}
632
633static int
634acpi_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
640static int
641acpi_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
647static 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
656static 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
674static 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
682static 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
769remove_links:
770	acpi_thermal_zone_sysfs_remove(tz);
771unregister_tzd:
772	thermal_zone_device_unregister(tz->thermal_zone);
773free_trip_table:
774	kfree(tz->trip_table);
775
776	return result;
777}
778
779static 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
792static 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 */
827static 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
847static 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 */
889static 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
898static 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
923static 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
965flush_wq:
966	flush_workqueue(acpi_thermal_pm_queue);
967	acpi_thermal_unregister_thermal_zone(tz);
968free_memory:
969	kfree(tz);
970
971	return result;
972}
973
974static 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
993static 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
1000static 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
1030static SIMPLE_DEV_PM_OPS(acpi_thermal_pm, acpi_thermal_suspend, acpi_thermal_resume);
1031
1032static const struct acpi_device_id  thermal_device_ids[] = {
1033	{ACPI_THERMAL_HID, 0},
1034	{"", 0},
1035};
1036MODULE_DEVICE_TABLE(acpi, thermal_device_ids);
1037
1038static 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
1049static 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}
1057static 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}
1063static 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}
1071static 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
1080static 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
1120static 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
1145static void __exit acpi_thermal_exit(void)
1146{
1147	acpi_bus_unregister_driver(&acpi_thermal_driver);
1148	destroy_workqueue(acpi_thermal_pm_queue);
1149}
1150
1151module_init(acpi_thermal_init);
1152module_exit(acpi_thermal_exit);
1153
1154MODULE_AUTHOR("Paul Diefenbaugh");
1155MODULE_DESCRIPTION("ACPI Thermal Zone Driver");
1156MODULE_LICENSE("GPL");
1157