1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 *  thermal.c - Generic Thermal Management Sysfs support.
   4 *
   5 *  Copyright (C) 2008 Intel Corp
   6 *  Copyright (C) 2008 Zhang Rui <rui.zhang@intel.com>
   7 *  Copyright (C) 2008 Sujith Thomas <sujith.thomas@intel.com>
   8 */
   9
  10#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  11
 
  12#include <linux/device.h>
  13#include <linux/err.h>
  14#include <linux/export.h>
  15#include <linux/slab.h>
  16#include <linux/kdev_t.h>
  17#include <linux/idr.h>
  18#include <linux/thermal.h>
  19#include <linux/reboot.h>
  20#include <linux/string.h>
  21#include <linux/of.h>
 
 
  22#include <linux/suspend.h>
  23
  24#define CREATE_TRACE_POINTS
  25#include "thermal_trace.h"
  26
  27#include "thermal_core.h"
  28#include "thermal_hwmon.h"
  29
 
 
 
 
  30static DEFINE_IDA(thermal_tz_ida);
  31static DEFINE_IDA(thermal_cdev_ida);
  32
  33static LIST_HEAD(thermal_tz_list);
  34static LIST_HEAD(thermal_cdev_list);
  35static LIST_HEAD(thermal_governor_list);
  36
  37static DEFINE_MUTEX(thermal_list_lock);
  38static DEFINE_MUTEX(thermal_governor_lock);
 
  39
  40static struct thermal_governor *def_governor;
 
  41
  42static bool thermal_pm_suspended;
  43
  44/*
  45 * Governor section: set of functions to handle thermal governors
  46 *
  47 * Functions to help in the life cycle of thermal governors within
  48 * the thermal core and by the thermal governor code.
  49 */
  50
  51static struct thermal_governor *__find_governor(const char *name)
  52{
  53	struct thermal_governor *pos;
  54
  55	if (!name || !name[0])
  56		return def_governor;
  57
  58	list_for_each_entry(pos, &thermal_governor_list, governor_list)
  59		if (!strncasecmp(name, pos->name, THERMAL_NAME_LENGTH))
  60			return pos;
  61
  62	return NULL;
  63}
  64
  65/**
  66 * bind_previous_governor() - bind the previous governor of the thermal zone
  67 * @tz:		a valid pointer to a struct thermal_zone_device
  68 * @failed_gov_name:	the name of the governor that failed to register
  69 *
  70 * Register the previous governor of the thermal zone after a new
  71 * governor has failed to be bound.
  72 */
  73static void bind_previous_governor(struct thermal_zone_device *tz,
  74				   const char *failed_gov_name)
  75{
  76	if (tz->governor && tz->governor->bind_to_tz) {
  77		if (tz->governor->bind_to_tz(tz)) {
  78			dev_err(&tz->device,
  79				"governor %s failed to bind and the previous one (%s) failed to bind again, thermal zone %s has no governor\n",
  80				failed_gov_name, tz->governor->name, tz->type);
  81			tz->governor = NULL;
  82		}
  83	}
  84}
  85
  86/**
  87 * thermal_set_governor() - Switch to another governor
  88 * @tz:		a valid pointer to a struct thermal_zone_device
  89 * @new_gov:	pointer to the new governor
  90 *
  91 * Change the governor of thermal zone @tz.
  92 *
  93 * Return: 0 on success, an error if the new governor's bind_to_tz() failed.
  94 */
  95static int thermal_set_governor(struct thermal_zone_device *tz,
  96				struct thermal_governor *new_gov)
  97{
  98	int ret = 0;
  99
 100	if (tz->governor && tz->governor->unbind_from_tz)
 101		tz->governor->unbind_from_tz(tz);
 102
 103	if (new_gov && new_gov->bind_to_tz) {
 104		ret = new_gov->bind_to_tz(tz);
 105		if (ret) {
 106			bind_previous_governor(tz, new_gov->name);
 107
 108			return ret;
 109		}
 110	}
 111
 112	tz->governor = new_gov;
 113
 114	return ret;
 115}
 116
 117int thermal_register_governor(struct thermal_governor *governor)
 118{
 119	int err;
 120	const char *name;
 121	struct thermal_zone_device *pos;
 122
 123	if (!governor)
 124		return -EINVAL;
 125
 126	guard(mutex)(&thermal_governor_lock);
 127
 128	err = -EBUSY;
 129	if (!__find_governor(governor->name)) {
 130		bool match_default;
 131
 132		err = 0;
 133		list_add(&governor->governor_list, &thermal_governor_list);
 134		match_default = !strncmp(governor->name,
 135					 DEFAULT_THERMAL_GOVERNOR,
 136					 THERMAL_NAME_LENGTH);
 137
 138		if (!def_governor && match_default)
 139			def_governor = governor;
 140	}
 141
 142	guard(mutex)(&thermal_list_lock);
 143
 144	list_for_each_entry(pos, &thermal_tz_list, node) {
 145		/*
 146		 * only thermal zones with specified tz->tzp->governor_name
 147		 * may run with tz->govenor unset
 148		 */
 149		if (pos->governor)
 150			continue;
 151
 152		name = pos->tzp->governor_name;
 153
 154		if (!strncasecmp(name, governor->name, THERMAL_NAME_LENGTH)) {
 155			int ret;
 156
 157			ret = thermal_set_governor(pos, governor);
 158			if (ret)
 159				dev_err(&pos->device,
 160					"Failed to set governor %s for thermal zone %s: %d\n",
 161					governor->name, pos->type, ret);
 162		}
 163	}
 164
 
 
 
 165	return err;
 166}
 167
 168void thermal_unregister_governor(struct thermal_governor *governor)
 169{
 170	struct thermal_zone_device *pos;
 171
 172	if (!governor)
 173		return;
 174
 175	guard(mutex)(&thermal_governor_lock);
 176
 177	if (!__find_governor(governor->name))
 178		return;
 179
 180	list_del(&governor->governor_list);
 181
 182	guard(mutex)(&thermal_list_lock);
 183
 184	list_for_each_entry(pos, &thermal_tz_list, node) {
 185		if (!strncasecmp(pos->governor->name, governor->name,
 186				 THERMAL_NAME_LENGTH))
 187			thermal_set_governor(pos, NULL);
 188	}
 
 
 
 
 
 189}
 190
 191int thermal_zone_device_set_policy(struct thermal_zone_device *tz,
 192				   char *policy)
 193{
 194	struct thermal_governor *gov;
 195	int ret = -EINVAL;
 196
 197	guard(mutex)(&thermal_governor_lock);
 198	guard(thermal_zone)(tz);
 199
 200	gov = __find_governor(strim(policy));
 201	if (gov)
 202		ret = thermal_set_governor(tz, gov);
 203
 204	thermal_notify_tz_gov_change(tz, policy);
 
 
 
 
 205
 206	return ret;
 207}
 208
 209int thermal_build_list_of_policies(char *buf)
 210{
 211	struct thermal_governor *pos;
 212	ssize_t count = 0;
 
 213
 214	guard(mutex)(&thermal_governor_lock);
 215
 216	list_for_each_entry(pos, &thermal_governor_list, governor_list) {
 217		count += sysfs_emit_at(buf, count, "%s ", pos->name);
 
 218	}
 219	count += sysfs_emit_at(buf, count, "\n");
 
 
 220
 221	return count;
 222}
 223
 224static void __init thermal_unregister_governors(void)
 225{
 226	struct thermal_governor **governor;
 227
 228	for_each_governor_table(governor)
 229		thermal_unregister_governor(*governor);
 230}
 231
 232static int __init thermal_register_governors(void)
 233{
 234	int ret = 0;
 235	struct thermal_governor **governor;
 236
 237	for_each_governor_table(governor) {
 238		ret = thermal_register_governor(*governor);
 239		if (ret) {
 240			pr_err("Failed to register governor: '%s'",
 241			       (*governor)->name);
 242			break;
 243		}
 244
 245		pr_info("Registered thermal governor '%s'",
 246			(*governor)->name);
 247	}
 248
 249	if (ret) {
 250		struct thermal_governor **gov;
 251
 252		for_each_governor_table(gov) {
 253			if (gov == governor)
 254				break;
 255			thermal_unregister_governor(*gov);
 256		}
 257	}
 258
 259	return ret;
 260}
 261
 262static int __thermal_zone_device_set_mode(struct thermal_zone_device *tz,
 263					  enum thermal_device_mode mode)
 264{
 265	if (tz->ops.change_mode) {
 266		int ret;
 267
 268		ret = tz->ops.change_mode(tz, mode);
 269		if (ret)
 270			return ret;
 271	}
 272
 273	tz->mode = mode;
 274
 275	return 0;
 276}
 277
 278static void thermal_zone_broken_disable(struct thermal_zone_device *tz)
 279{
 280	struct thermal_trip_desc *td;
 281
 282	dev_err(&tz->device, "Unable to get temperature, disabling!\n");
 283	/*
 284	 * This function only runs for enabled thermal zones, so no need to
 285	 * check for the current mode.
 286	 */
 287	__thermal_zone_device_set_mode(tz, THERMAL_DEVICE_DISABLED);
 288	thermal_notify_tz_disable(tz);
 289
 290	for_each_trip_desc(tz, td) {
 291		if (td->trip.type == THERMAL_TRIP_CRITICAL &&
 292		    td->trip.temperature > THERMAL_TEMP_INVALID) {
 293			dev_crit(&tz->device,
 294				 "Disabled thermal zone with critical trip point\n");
 295			return;
 296		}
 297	}
 298}
 299
 300/*
 301 * Zone update section: main control loop applied to each zone while monitoring
 
 302 * in polling mode. The monitoring is done using a workqueue.
 303 * Same update may be done on a zone by calling thermal_zone_device_update().
 304 *
 305 * An update means:
 306 * - Non-critical trips will invoke the governor responsible for that zone;
 307 * - Hot trips will produce a notification to userspace;
 308 * - Critical trip point will cause a system shutdown.
 309 */
 310static void thermal_zone_device_set_polling(struct thermal_zone_device *tz,
 311					    unsigned long delay)
 312{
 313	if (delay > HZ)
 314		delay = round_jiffies_relative(delay);
 315
 316	mod_delayed_work(system_freezable_power_efficient_wq, &tz->poll_queue, delay);
 317}
 318
 319static void thermal_zone_recheck(struct thermal_zone_device *tz, int error)
 320{
 321	if (error == -EAGAIN) {
 322		thermal_zone_device_set_polling(tz, THERMAL_RECHECK_DELAY);
 323		return;
 324	}
 325
 326	/*
 327	 * Print the message once to reduce log noise.  It will be followed by
 328	 * another one if the temperature cannot be determined after multiple
 329	 * attempts.
 330	 */
 331	if (tz->recheck_delay_jiffies == THERMAL_RECHECK_DELAY)
 332		dev_info(&tz->device, "Temperature check failed (%d)\n", error);
 333
 334	thermal_zone_device_set_polling(tz, tz->recheck_delay_jiffies);
 335
 336	tz->recheck_delay_jiffies += max(tz->recheck_delay_jiffies >> 1, 1ULL);
 337	if (tz->recheck_delay_jiffies > THERMAL_MAX_RECHECK_DELAY) {
 338		thermal_zone_broken_disable(tz);
 339		/*
 340		 * Restore the original recheck delay value to allow the thermal
 341		 * zone to try to recover when it is reenabled by user space.
 342		 */
 343		tz->recheck_delay_jiffies = THERMAL_RECHECK_DELAY;
 344	}
 345}
 346
 347static void monitor_thermal_zone(struct thermal_zone_device *tz)
 348{
 349	if (tz->passive > 0 && tz->passive_delay_jiffies)
 350		thermal_zone_device_set_polling(tz, tz->passive_delay_jiffies);
 351	else if (tz->polling_delay_jiffies)
 352		thermal_zone_device_set_polling(tz, tz->polling_delay_jiffies);
 353}
 354
 355static struct thermal_governor *thermal_get_tz_governor(struct thermal_zone_device *tz)
 356{
 357	if (tz->governor)
 358		return tz->governor;
 
 
 359
 360	return def_governor;
 361}
 362
 363void thermal_governor_update_tz(struct thermal_zone_device *tz,
 364				enum thermal_notify_event reason)
 365{
 366	if (!tz->governor || !tz->governor->update_tz)
 367		return;
 368
 369	tz->governor->update_tz(tz, reason);
 370}
 371
 372static void thermal_zone_device_halt(struct thermal_zone_device *tz, bool shutdown)
 
 
 
 
 
 
 
 373{
 374	/*
 375	 * poweroff_delay_ms must be a carefully profiled positive value.
 376	 * Its a must for forced_emergency_poweroff_work to be scheduled.
 
 
 
 377	 */
 378	int poweroff_delay_ms = CONFIG_THERMAL_EMERGENCY_POWEROFF_DELAY_MS;
 379	const char *msg = "Temperature too high";
 380
 381	dev_emerg(&tz->device, "%s: critical temperature reached\n", tz->type);
 382
 383	if (shutdown)
 384		hw_protection_shutdown(msg, poweroff_delay_ms);
 385	else
 386		hw_protection_reboot(msg, poweroff_delay_ms);
 387}
 388
 389void thermal_zone_device_critical(struct thermal_zone_device *tz)
 390{
 391	thermal_zone_device_halt(tz, true);
 392}
 393EXPORT_SYMBOL(thermal_zone_device_critical);
 394
 395void thermal_zone_device_critical_reboot(struct thermal_zone_device *tz)
 396{
 397	thermal_zone_device_halt(tz, false);
 
 
 398}
 399
 400static void handle_critical_trips(struct thermal_zone_device *tz,
 401				  const struct thermal_trip *trip)
 402{
 403	trace_thermal_zone_trip(tz, thermal_zone_trip_id(tz, trip), trip->type);
 404
 405	if (trip->type == THERMAL_TRIP_CRITICAL)
 406		tz->ops.critical(tz);
 407	else if (tz->ops.hot)
 408		tz->ops.hot(tz);
 409}
 410
 411static void move_trip_to_sorted_list(struct thermal_trip_desc *td,
 412				     struct list_head *list)
 
 
 
 
 
 413{
 414	struct thermal_trip_desc *entry;
 415
 416	/*
 417	 * Delete upfront and then add to make relocation within the same list
 418	 * work.
 419	 */
 420	list_del(&td->list_node);
 421
 422	/* Assume that the new entry is likely to be the last one. */
 423	list_for_each_entry_reverse(entry, list, list_node) {
 424		if (entry->threshold <= td->threshold) {
 425			list_add(&td->list_node, &entry->list_node);
 426			return;
 427		}
 428	}
 429	list_add(&td->list_node, list);
 430}
 431
 432static void move_to_trips_high(struct thermal_zone_device *tz,
 433			       struct thermal_trip_desc *td)
 434{
 435	td->threshold = td->trip.temperature;
 436	move_trip_to_sorted_list(td, &tz->trips_high);
 437}
 438
 439static void move_to_trips_reached(struct thermal_zone_device *tz,
 440				  struct thermal_trip_desc *td)
 441{
 442	td->threshold = td->trip.temperature - td->trip.hysteresis;
 443	move_trip_to_sorted_list(td, &tz->trips_reached);
 444}
 445
 446static void move_to_trips_invalid(struct thermal_zone_device *tz,
 447				  struct thermal_trip_desc *td)
 448{
 449	td->threshold = INT_MAX;
 450	list_move(&td->list_node, &tz->trips_invalid);
 451}
 452
 453static void thermal_governor_trip_crossed(struct thermal_governor *governor,
 454					  struct thermal_zone_device *tz,
 455					  const struct thermal_trip *trip,
 456					  bool crossed_up)
 457{
 458	if (trip->type == THERMAL_TRIP_HOT || trip->type == THERMAL_TRIP_CRITICAL)
 459		return;
 460
 461	if (governor->trip_crossed)
 462		governor->trip_crossed(tz, trip, crossed_up);
 463}
 464
 465static void thermal_trip_crossed(struct thermal_zone_device *tz,
 466				 struct thermal_trip_desc *td,
 467				 struct thermal_governor *governor,
 468				 bool crossed_up)
 469{
 470	const struct thermal_trip *trip = &td->trip;
 471
 472	if (crossed_up) {
 473		if (trip->type == THERMAL_TRIP_PASSIVE)
 474			tz->passive++;
 475		else if (trip->type == THERMAL_TRIP_CRITICAL ||
 476			 trip->type == THERMAL_TRIP_HOT)
 477			handle_critical_trips(tz, trip);
 478
 479		thermal_notify_tz_trip_up(tz, trip);
 480		thermal_debug_tz_trip_up(tz, trip);
 481	} else {
 482		if (trip->type == THERMAL_TRIP_PASSIVE) {
 483			tz->passive--;
 484			WARN_ON(tz->passive < 0);
 485		}
 486		thermal_notify_tz_trip_down(tz, trip);
 487		thermal_debug_tz_trip_down(tz, trip);
 488	}
 489	thermal_governor_trip_crossed(governor, tz, trip, crossed_up);
 490}
 491
 492void thermal_zone_set_trip_hyst(struct thermal_zone_device *tz,
 493				struct thermal_trip *trip, int hyst)
 494{
 495	struct thermal_trip_desc *td = trip_to_trip_desc(trip);
 496
 497	WRITE_ONCE(trip->hysteresis, hyst);
 498	thermal_notify_tz_trip_change(tz, trip);
 499	/*
 500	 * If the zone temperature is above or at the trip tmperature, the trip
 501	 * is in the trips_reached list and its threshold is equal to its low
 502	 * temperature.  It needs to stay in that list, but its threshold needs
 503	 * to be updated and the list ordering may need to be restored.
 504	 */
 505	if (tz->temperature >= td->threshold)
 506		move_to_trips_reached(tz, td);
 507}
 508
 509void thermal_zone_set_trip_temp(struct thermal_zone_device *tz,
 510				struct thermal_trip *trip, int temp)
 511{
 512	struct thermal_trip_desc *td = trip_to_trip_desc(trip);
 513	int old_temp = trip->temperature;
 514
 515	if (old_temp == temp)
 516		return;
 517
 518	WRITE_ONCE(trip->temperature, temp);
 519	thermal_notify_tz_trip_change(tz, trip);
 520
 521	if (old_temp == THERMAL_TEMP_INVALID) {
 522		/*
 523		 * The trip was invalid before the change, so move it to the
 524		 * trips_high list regardless of the new temperature value
 525		 * because there is no mitigation under way for it.  If a
 526		 * mitigation needs to be started, the trip will be moved to the
 527		 * trips_reached list later.
 528		 */
 529		move_to_trips_high(tz, td);
 530		return;
 531	}
 532
 533	if (temp == THERMAL_TEMP_INVALID) {
 534		/*
 535		 * If the trip is in the trips_reached list, mitigation is under
 536		 * way for it and it needs to be stopped because the trip is
 537		 * effectively going away.
 538		 */
 539		if (tz->temperature >= td->threshold)
 540			thermal_trip_crossed(tz, td, thermal_get_tz_governor(tz), false);
 541
 542		move_to_trips_invalid(tz, td);
 543		return;
 544	}
 545
 
 
 
 
 546	/*
 547	 * The trip stays on its current list, but its threshold needs to be
 548	 * updated due to the temperature change and the list ordering may need
 549	 * to be restored.
 550	 */
 551	if (tz->temperature >= td->threshold)
 552		move_to_trips_reached(tz, td);
 553	else
 554		move_to_trips_high(tz, td);
 555}
 556EXPORT_SYMBOL_GPL(thermal_zone_set_trip_temp);
 557
 558static void thermal_zone_handle_trips(struct thermal_zone_device *tz,
 559				      struct thermal_governor *governor,
 560				      int *low, int *high)
 561{
 562	struct thermal_trip_desc *td, *next;
 563	LIST_HEAD(way_down_list);
 564
 565	/* Check the trips that were below or at the zone temperature. */
 566	list_for_each_entry_safe_reverse(td, next, &tz->trips_reached, list_node) {
 567		if (td->threshold <= tz->temperature)
 568			break;
 569
 570		thermal_trip_crossed(tz, td, governor, false);
 571		/*
 572		 * The current trips_high list needs to be processed before
 573		 * adding new entries to it, so put them on a temporary list.
 574		 */
 575		list_move(&td->list_node, &way_down_list);
 576	}
 577	/* Check the trips that were previously above the zone temperature. */
 578	list_for_each_entry_safe(td, next, &tz->trips_high, list_node) {
 579		if (td->threshold > tz->temperature)
 580			break;
 581
 582		thermal_trip_crossed(tz, td, governor, true);
 583		move_to_trips_reached(tz, td);
 584	}
 585	/* Move all of the trips from the temporary list to trips_high. */
 586	list_for_each_entry_safe(td, next, &way_down_list, list_node)
 587		move_to_trips_high(tz, td);
 588
 589	if (!list_empty(&tz->trips_reached)) {
 590		td = list_last_entry(&tz->trips_reached,
 591				     struct thermal_trip_desc, list_node);
 592		/*
 593		 * Set the "low" value below the current trip threshold in case
 594		 * the zone temperature is at that threshold and stays there,
 595		 * which would trigger a new interrupt immediately in vain.
 596		 */
 597		*low = td->threshold - 1;
 598	}
 599	if (!list_empty(&tz->trips_high)) {
 600		td = list_first_entry(&tz->trips_high,
 601				      struct thermal_trip_desc, list_node);
 602		*high = td->threshold;
 603	}
 604}
 605
 606void __thermal_zone_device_update(struct thermal_zone_device *tz,
 607				  enum thermal_notify_event event)
 608{
 609	struct thermal_governor *governor = thermal_get_tz_governor(tz);
 610	int low = -INT_MAX, high = INT_MAX;
 611	int temp, ret;
 612
 613	if (tz->state != TZ_STATE_READY || tz->mode != THERMAL_DEVICE_ENABLED)
 614		return;
 615
 616	ret = __thermal_zone_get_temp(tz, &temp);
 617	if (ret) {
 618		thermal_zone_recheck(tz, ret);
 
 
 
 619		return;
 620	} else if (temp <= THERMAL_TEMP_INVALID) {
 621		/*
 622		 * Special case: No valid temperature value is available, but
 623		 * the zone owner does not want the core to do anything about
 624		 * it.  Continue regular zone polling if needed, so that this
 625		 * function can be called again, but skip everything else.
 626		 */
 627		goto monitor;
 628	}
 629
 630	tz->recheck_delay_jiffies = THERMAL_RECHECK_DELAY;
 631
 632	tz->last_temperature = tz->temperature;
 633	tz->temperature = temp;
 
 634
 635	trace_thermal_temperature(tz);
 
 
 
 
 
 
 
 636
 637	thermal_genl_sampling_temp(tz->id, temp);
 638
 639	tz->notify_event = event;
 640
 641	thermal_zone_handle_trips(tz, governor, &low, &high);
 642
 643	thermal_thresholds_handle(tz, &low, &high);
 644
 645	thermal_zone_set_trips(tz, low, high);
 646
 647	if (governor->manage)
 648		governor->manage(tz);
 649
 650	thermal_debug_update_trip_stats(tz);
 651
 652monitor:
 653	monitor_thermal_zone(tz);
 
 
 654}
 655
 656static int thermal_zone_device_set_mode(struct thermal_zone_device *tz,
 657					enum thermal_device_mode mode)
 658{
 659	int ret;
 660
 661	guard(thermal_zone)(tz);
 
 662
 663	/* do nothing if mode isn't changing */
 664	if (mode == tz->mode)
 665		return 0;
 666
 667	ret = __thermal_zone_device_set_mode(tz, mode);
 668	if (ret)
 669		return ret;
 670
 671	__thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
 672
 673	if (mode == THERMAL_DEVICE_ENABLED)
 674		thermal_notify_tz_enable(tz);
 675	else
 676		thermal_notify_tz_disable(tz);
 677
 678	return 0;
 
 679}
 
 680
 681int thermal_zone_device_enable(struct thermal_zone_device *tz)
 
 
 
 
 
 
 
 
 
 
 
 
 682{
 683	return thermal_zone_device_set_mode(tz, THERMAL_DEVICE_ENABLED);
 684}
 685EXPORT_SYMBOL_GPL(thermal_zone_device_enable);
 686
 687int thermal_zone_device_disable(struct thermal_zone_device *tz)
 688{
 689	return thermal_zone_device_set_mode(tz, THERMAL_DEVICE_DISABLED);
 
 
 
 690}
 691EXPORT_SYMBOL_GPL(thermal_zone_device_disable);
 692
 693static bool thermal_zone_is_present(struct thermal_zone_device *tz)
 694{
 695	return !list_empty(&tz->node);
 696}
 
 
 697
 698void thermal_zone_device_update(struct thermal_zone_device *tz,
 699				enum thermal_notify_event event)
 
 
 
 
 
 
 
 
 
 
 
 
 700{
 701	guard(thermal_zone)(tz);
 
 702
 703	if (thermal_zone_is_present(tz))
 704		__thermal_zone_device_update(tz, event);
 705}
 706EXPORT_SYMBOL_GPL(thermal_zone_device_update);
 707
 708int for_each_thermal_governor(int (*cb)(struct thermal_governor *, void *),
 709			      void *data)
 
 
 
 
 
 
 
 
 
 
 
 
 710{
 711	struct thermal_governor *gov;
 712
 713	guard(mutex)(&thermal_governor_lock);
 714
 715	list_for_each_entry(gov, &thermal_governor_list, governor_list) {
 716		int ret;
 717
 718		ret = cb(gov, data);
 719		if (ret)
 720			return ret;
 721	}
 722
 723	return 0;
 724}
 725
 726int for_each_thermal_cooling_device(int (*cb)(struct thermal_cooling_device *,
 727					      void *), void *data)
 
 
 
 
 
 
 
 
 
 
 
 
 728{
 729	struct thermal_cooling_device *cdev;
 
 730
 731	guard(mutex)(&thermal_list_lock);
 
 732
 733	list_for_each_entry(cdev, &thermal_cdev_list, node) {
 734		int ret;
 
 735
 736		ret = cb(cdev, data);
 737		if (ret)
 738			return ret;
 739	}
 
 740
 741	return 0;
 742}
 743
 744int for_each_thermal_zone(int (*cb)(struct thermal_zone_device *, void *),
 745			  void *data)
 746{
 747	struct thermal_zone_device *tz;
 748
 749	guard(mutex)(&thermal_list_lock);
 750
 751	list_for_each_entry(tz, &thermal_tz_list, node) {
 752		int ret;
 
 753
 754		ret = cb(tz, data);
 755		if (ret)
 756			return ret;
 
 
 757	}
 758
 759	return 0;
 760}
 761
 762struct thermal_zone_device *thermal_zone_get_by_id(int id)
 
 763{
 764	struct thermal_zone_device *tz;
 765
 766	guard(mutex)(&thermal_list_lock);
 767
 768	list_for_each_entry(tz, &thermal_tz_list, node) {
 769		if (tz->id == id) {
 770			get_device(&tz->device);
 771			return tz;
 772		}
 
 
 
 773	}
 774
 775	return NULL;
 776}
 777
 778/*
 779 * Device management section: cooling devices, zones devices, and binding
 780 *
 781 * Set of functions provided by the thermal core for:
 782 * - cooling devices lifecycle: registration, unregistration,
 783 *				binding, and unbinding.
 784 * - thermal zone devices lifecycle: registration, unregistration,
 785 *				     binding, and unbinding.
 786 */
 787
 788static int thermal_instance_add(struct thermal_instance *new_instance,
 789				struct thermal_cooling_device *cdev,
 790				struct thermal_trip_desc *td)
 791{
 792	struct thermal_instance *instance;
 793
 794	list_for_each_entry(instance, &td->thermal_instances, trip_node) {
 795		if (instance->cdev == cdev)
 796			return -EEXIST;
 797	}
 798
 799	list_add_tail(&new_instance->trip_node, &td->thermal_instances);
 800
 801	guard(cooling_dev)(cdev);
 802
 803	list_add_tail(&new_instance->cdev_node, &cdev->thermal_instances);
 804
 805	return 0;
 806}
 807
 808/**
 809 * thermal_bind_cdev_to_trip - bind a cooling device to a thermal zone
 810 * @tz:		pointer to struct thermal_zone_device
 811 * @td:		descriptor of the trip point to bind @cdev to
 
 812 * @cdev:	pointer to struct thermal_cooling_device
 813 * @cool_spec:	cooling specification for the trip point and @cdev
 
 
 
 
 
 
 
 
 814 *
 815 * This interface function bind a thermal cooling device to the certain trip
 816 * point of a thermal zone device.
 817 * This function is usually called in the thermal zone device .bind callback.
 818 *
 819 * Return: 0 on success, the proper error value otherwise.
 820 */
 821static int thermal_bind_cdev_to_trip(struct thermal_zone_device *tz,
 822				     struct thermal_trip_desc *td,
 823				     struct thermal_cooling_device *cdev,
 824				     struct cooling_spec *cool_spec)
 
 825{
 826	struct thermal_instance *dev;
 827	bool upper_no_limit;
 828	int result;
 
 
 
 829
 830	/* lower default 0, upper default max_state */
 831	if (cool_spec->lower == THERMAL_NO_LIMIT)
 832		cool_spec->lower = 0;
 833
 834	if (cool_spec->upper == THERMAL_NO_LIMIT) {
 835		cool_spec->upper = cdev->max_state;
 836		upper_no_limit = true;
 837	} else {
 838		upper_no_limit = false;
 
 
 839	}
 840
 841	if (cool_spec->lower > cool_spec->upper || cool_spec->upper > cdev->max_state)
 
 
 
 
 
 
 
 
 
 
 
 842		return -EINVAL;
 843
 844	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
 845	if (!dev)
 846		return -ENOMEM;
 847
 848	dev->cdev = cdev;
 849	dev->trip = &td->trip;
 850	dev->upper = cool_spec->upper;
 851	dev->upper_no_limit = upper_no_limit;
 852	dev->lower = cool_spec->lower;
 853	dev->target = THERMAL_NO_TARGET;
 854	dev->weight = cool_spec->weight;
 855
 856	result = ida_alloc(&tz->ida, GFP_KERNEL);
 857	if (result < 0)
 858		goto free_mem;
 859
 860	dev->id = result;
 861	sprintf(dev->name, "cdev%d", dev->id);
 862	result =
 863	    sysfs_create_link(&tz->device.kobj, &cdev->device.kobj, dev->name);
 864	if (result)
 865		goto release_ida;
 866
 867	snprintf(dev->attr_name, sizeof(dev->attr_name), "cdev%d_trip_point",
 868		 dev->id);
 869	sysfs_attr_init(&dev->attr.attr);
 870	dev->attr.attr.name = dev->attr_name;
 871	dev->attr.attr.mode = 0444;
 872	dev->attr.show = trip_point_show;
 873	result = device_create_file(&tz->device, &dev->attr);
 874	if (result)
 875		goto remove_symbol_link;
 876
 877	snprintf(dev->weight_attr_name, sizeof(dev->weight_attr_name),
 878		 "cdev%d_weight", dev->id);
 879	sysfs_attr_init(&dev->weight_attr.attr);
 880	dev->weight_attr.attr.name = dev->weight_attr_name;
 881	dev->weight_attr.attr.mode = S_IWUSR | S_IRUGO;
 882	dev->weight_attr.show = weight_show;
 883	dev->weight_attr.store = weight_store;
 884	result = device_create_file(&tz->device, &dev->weight_attr);
 885	if (result)
 886		goto remove_trip_file;
 887
 888	result = thermal_instance_add(dev, cdev, td);
 889	if (result)
 890		goto remove_weight_file;
 891
 892	thermal_governor_update_tz(tz, THERMAL_TZ_BIND_CDEV);
 
 
 
 
 
 
 
 
 
 893
 894	return 0;
 
 895
 896remove_weight_file:
 897	device_remove_file(&tz->device, &dev->weight_attr);
 898remove_trip_file:
 899	device_remove_file(&tz->device, &dev->attr);
 900remove_symbol_link:
 901	sysfs_remove_link(&tz->device.kobj, dev->name);
 902release_ida:
 903	ida_free(&tz->ida, dev->id);
 904free_mem:
 905	kfree(dev);
 906	return result;
 907}
 908
 909static void thermal_instance_delete(struct thermal_instance *instance)
 910{
 911	list_del(&instance->trip_node);
 912
 913	guard(cooling_dev)(instance->cdev);
 914
 915	list_del(&instance->cdev_node);
 916}
 917
 918/**
 919 * thermal_unbind_cdev_from_trip - unbind a cooling device from a thermal zone.
 
 920 * @tz:		pointer to a struct thermal_zone_device.
 921 * @td:		descriptor of the trip point to unbind @cdev from
 
 922 * @cdev:	pointer to a struct thermal_cooling_device.
 923 *
 924 * This interface function unbind a thermal cooling device from the certain
 925 * trip point of a thermal zone device.
 926 * This function is usually called in the thermal zone device .unbind callback.
 
 
 927 */
 928static void thermal_unbind_cdev_from_trip(struct thermal_zone_device *tz,
 929					  struct thermal_trip_desc *td,
 930					  struct thermal_cooling_device *cdev)
 931{
 932	struct thermal_instance *pos, *next;
 933
 934	list_for_each_entry_safe(pos, next, &td->thermal_instances, trip_node) {
 935		if (pos->cdev == cdev) {
 936			thermal_instance_delete(pos);
 
 
 
 
 
 937			goto unbind;
 938		}
 939	}
 
 
 940
 941	return;
 942
 943unbind:
 944	thermal_governor_update_tz(tz, THERMAL_TZ_UNBIND_CDEV);
 945
 946	device_remove_file(&tz->device, &pos->weight_attr);
 947	device_remove_file(&tz->device, &pos->attr);
 948	sysfs_remove_link(&tz->device.kobj, pos->name);
 949	ida_free(&tz->ida, pos->id);
 950	kfree(pos);
 
 951}
 
 952
 953static void thermal_release(struct device *dev)
 954{
 955	struct thermal_zone_device *tz;
 956	struct thermal_cooling_device *cdev;
 957
 958	if (!strncmp(dev_name(dev), "thermal_zone",
 959		     sizeof("thermal_zone") - 1)) {
 960		tz = to_thermal_zone(dev);
 961		thermal_zone_destroy_device_groups(tz);
 962		mutex_destroy(&tz->lock);
 963		complete(&tz->removal);
 964	} else if (!strncmp(dev_name(dev), "cooling_device",
 965			    sizeof("cooling_device") - 1)) {
 966		cdev = to_cooling_device(dev);
 967		thermal_cooling_device_destroy_sysfs(cdev);
 968		kfree_const(cdev->type);
 969		ida_free(&thermal_cdev_ida, cdev->id);
 970		kfree(cdev);
 971	}
 972}
 973
 974static struct class *thermal_class;
 
 
 
 975
 976static inline
 977void print_bind_err_msg(struct thermal_zone_device *tz,
 978			const struct thermal_trip_desc *td,
 979			struct thermal_cooling_device *cdev, int ret)
 980{
 981	dev_err(&tz->device, "binding cdev %s to trip %d failed: %d\n",
 982		cdev->type, thermal_zone_trip_id(tz, &td->trip), ret);
 983}
 984
 985static bool __thermal_zone_cdev_bind(struct thermal_zone_device *tz,
 986				     struct thermal_cooling_device *cdev)
 987{
 988	struct thermal_trip_desc *td;
 989	bool update_tz = false;
 990
 991	if (!tz->ops.should_bind)
 992		return false;
 993
 994	for_each_trip_desc(tz, td) {
 995		struct cooling_spec c = {
 996			.upper = THERMAL_NO_LIMIT,
 997			.lower = THERMAL_NO_LIMIT,
 998			.weight = THERMAL_WEIGHT_DEFAULT
 999		};
1000		int ret;
1001
1002		if (!tz->ops.should_bind(tz, &td->trip, cdev, &c))
1003			continue;
1004
1005		ret = thermal_bind_cdev_to_trip(tz, td, cdev, &c);
1006		if (ret) {
1007			print_bind_err_msg(tz, td, cdev, ret);
1008			continue;
1009		}
1010
1011		update_tz = true;
1012	}
1013
1014	return update_tz;
1015}
1016
1017static void thermal_zone_cdev_bind(struct thermal_zone_device *tz,
1018				   struct thermal_cooling_device *cdev)
1019{
1020	guard(thermal_zone)(tz);
 
 
1021
1022	if (__thermal_zone_cdev_bind(tz, cdev))
1023		__thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
1024}
1025
1026static void thermal_cooling_device_init_complete(struct thermal_cooling_device *cdev)
1027{
1028	struct thermal_zone_device *tz;
1029
1030	guard(mutex)(&thermal_list_lock);
 
 
 
 
 
1031
1032	list_add(&cdev->node, &thermal_cdev_list);
 
 
1033
1034	list_for_each_entry(tz, &thermal_tz_list, node)
1035		thermal_zone_cdev_bind(tz, cdev);
 
 
 
 
 
 
 
 
 
 
 
1036}
1037
1038/**
1039 * __thermal_cooling_device_register() - register a new thermal cooling device
1040 * @np:		a pointer to a device tree node.
1041 * @type:	the thermal cooling device type.
1042 * @devdata:	device private data.
1043 * @ops:		standard thermal cooling devices callbacks.
1044 *
1045 * This interface function adds a new thermal cooling device (fan/processor/...)
1046 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1047 * to all the thermal zone devices registered at the same time.
1048 * It also gives the opportunity to link the cooling device to a device tree
1049 * node, so that it can be bound to a thermal zone created out of device tree.
1050 *
1051 * Return: a pointer to the created struct thermal_cooling_device or an
1052 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1053 */
1054static struct thermal_cooling_device *
1055__thermal_cooling_device_register(struct device_node *np,
1056				  const char *type, void *devdata,
1057				  const struct thermal_cooling_device_ops *ops)
1058{
1059	struct thermal_cooling_device *cdev;
1060	unsigned long current_state;
1061	int id, ret;
 
 
 
1062
1063	if (!ops || !ops->get_max_state || !ops->get_cur_state ||
1064	    !ops->set_cur_state)
1065		return ERR_PTR(-EINVAL);
1066
1067	if (!thermal_class)
1068		return ERR_PTR(-ENODEV);
1069
1070	cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
1071	if (!cdev)
1072		return ERR_PTR(-ENOMEM);
1073
1074	ret = ida_alloc(&thermal_cdev_ida, GFP_KERNEL);
1075	if (ret < 0)
1076		goto out_kfree_cdev;
1077	cdev->id = ret;
1078	id = ret;
1079
1080	cdev->type = kstrdup_const(type ? type : "", GFP_KERNEL);
1081	if (!cdev->type) {
1082		ret = -ENOMEM;
1083		goto out_ida_remove;
1084	}
1085
 
 
1086	mutex_init(&cdev->lock);
1087	INIT_LIST_HEAD(&cdev->thermal_instances);
1088	cdev->np = np;
1089	cdev->ops = ops;
1090	cdev->updated = false;
1091	cdev->device.class = thermal_class;
1092	cdev->devdata = devdata;
1093
1094	ret = cdev->ops->get_max_state(cdev, &cdev->max_state);
1095	if (ret)
1096		goto out_cdev_type;
1097
1098	/*
1099	 * The cooling device's current state is only needed for debug
1100	 * initialization below, so a failure to get it does not cause
1101	 * the entire cooling device initialization to fail.  However,
1102	 * the debug will not work for the device if its initial state
1103	 * cannot be determined and drivers are responsible for ensuring
1104	 * that this will not happen.
1105	 */
1106	ret = cdev->ops->get_cur_state(cdev, &current_state);
1107	if (ret)
1108		current_state = ULONG_MAX;
1109
1110	thermal_cooling_device_setup_sysfs(cdev);
1111
1112	ret = dev_set_name(&cdev->device, "cooling_device%d", cdev->id);
1113	if (ret)
1114		goto out_cooling_dev;
1115
1116	ret = device_register(&cdev->device);
1117	if (ret) {
1118		/* thermal_release() handles rest of the cleanup */
1119		put_device(&cdev->device);
1120		return ERR_PTR(ret);
1121	}
1122
1123	if (current_state <= cdev->max_state)
1124		thermal_debug_cdev_add(cdev, current_state);
 
 
1125
1126	thermal_cooling_device_init_complete(cdev);
 
1127
1128	return cdev;
 
 
 
 
 
1129
1130out_cooling_dev:
1131	thermal_cooling_device_destroy_sysfs(cdev);
1132out_cdev_type:
1133	kfree_const(cdev->type);
1134out_ida_remove:
1135	ida_free(&thermal_cdev_ida, id);
1136out_kfree_cdev:
1137	kfree(cdev);
1138	return ERR_PTR(ret);
1139}
1140
1141/**
1142 * thermal_cooling_device_register() - register a new thermal cooling device
1143 * @type:	the thermal cooling device type.
1144 * @devdata:	device private data.
1145 * @ops:		standard thermal cooling devices callbacks.
1146 *
1147 * This interface function adds a new thermal cooling device (fan/processor/...)
1148 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1149 * to all the thermal zone devices registered at the same time.
1150 *
1151 * Return: a pointer to the created struct thermal_cooling_device or an
1152 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1153 */
1154struct thermal_cooling_device *
1155thermal_cooling_device_register(const char *type, void *devdata,
1156				const struct thermal_cooling_device_ops *ops)
1157{
1158	return __thermal_cooling_device_register(NULL, type, devdata, ops);
1159}
1160EXPORT_SYMBOL_GPL(thermal_cooling_device_register);
1161
1162/**
1163 * thermal_of_cooling_device_register() - register an OF thermal cooling device
1164 * @np:		a pointer to a device tree node.
1165 * @type:	the thermal cooling device type.
1166 * @devdata:	device private data.
1167 * @ops:		standard thermal cooling devices callbacks.
1168 *
1169 * This function will register a cooling device with device tree node reference.
1170 * This interface function adds a new thermal cooling device (fan/processor/...)
1171 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1172 * to all the thermal zone devices registered at the same time.
1173 *
1174 * Return: a pointer to the created struct thermal_cooling_device or an
1175 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1176 */
1177struct thermal_cooling_device *
1178thermal_of_cooling_device_register(struct device_node *np,
1179				   const char *type, void *devdata,
1180				   const struct thermal_cooling_device_ops *ops)
1181{
1182	return __thermal_cooling_device_register(np, type, devdata, ops);
1183}
1184EXPORT_SYMBOL_GPL(thermal_of_cooling_device_register);
1185
1186static void thermal_cooling_device_release(struct device *dev, void *res)
1187{
1188	thermal_cooling_device_unregister(
1189				*(struct thermal_cooling_device **)res);
1190}
1191
1192/**
1193 * devm_thermal_of_cooling_device_register() - register an OF thermal cooling
1194 *					       device
1195 * @dev:	a valid struct device pointer of a sensor device.
1196 * @np:		a pointer to a device tree node.
1197 * @type:	the thermal cooling device type.
1198 * @devdata:	device private data.
1199 * @ops:	standard thermal cooling devices callbacks.
1200 *
1201 * This function will register a cooling device with device tree node reference.
1202 * This interface function adds a new thermal cooling device (fan/processor/...)
1203 * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
1204 * to all the thermal zone devices registered at the same time.
1205 *
1206 * Return: a pointer to the created struct thermal_cooling_device or an
1207 * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
1208 */
1209struct thermal_cooling_device *
1210devm_thermal_of_cooling_device_register(struct device *dev,
1211				struct device_node *np,
1212				const char *type, void *devdata,
1213				const struct thermal_cooling_device_ops *ops)
1214{
1215	struct thermal_cooling_device **ptr, *tcd;
1216
1217	ptr = devres_alloc(thermal_cooling_device_release, sizeof(*ptr),
1218			   GFP_KERNEL);
1219	if (!ptr)
1220		return ERR_PTR(-ENOMEM);
1221
1222	tcd = __thermal_cooling_device_register(np, type, devdata, ops);
1223	if (IS_ERR(tcd)) {
1224		devres_free(ptr);
1225		return tcd;
1226	}
1227
1228	*ptr = tcd;
1229	devres_add(dev, ptr);
1230
1231	return tcd;
1232}
1233EXPORT_SYMBOL_GPL(devm_thermal_of_cooling_device_register);
1234
1235static bool thermal_cooling_device_present(struct thermal_cooling_device *cdev)
 
1236{
1237	struct thermal_cooling_device *pos = NULL;
1238
1239	list_for_each_entry(pos, &thermal_cdev_list, node) {
1240		if (pos == cdev)
1241			return true;
1242	}
1243
1244	return false;
 
 
1245}
1246
1247/**
1248 * thermal_cooling_device_update - Update a cooling device object
1249 * @cdev: Target cooling device.
1250 *
1251 * Update @cdev to reflect a change of the underlying hardware or platform.
1252 *
1253 * Must be called when the maximum cooling state of @cdev becomes invalid and so
1254 * its .get_max_state() callback needs to be run to produce the new maximum
1255 * cooling state value.
1256 */
1257void thermal_cooling_device_update(struct thermal_cooling_device *cdev)
1258{
1259	struct thermal_instance *ti;
1260	unsigned long state;
1261
1262	if (IS_ERR_OR_NULL(cdev))
1263		return;
1264
1265	/*
1266	 * Hold thermal_list_lock throughout the update to prevent the device
1267	 * from going away while being updated.
1268	 */
1269	guard(mutex)(&thermal_list_lock);
1270
1271	if (!thermal_cooling_device_present(cdev))
1272		return;
1273
1274	/*
1275	 * Update under the cdev lock to prevent the state from being set beyond
1276	 * the new limit concurrently.
1277	 */
1278	guard(cooling_dev)(cdev);
1279
1280	if (cdev->ops->get_max_state(cdev, &cdev->max_state))
1281		return;
 
 
1282
1283	thermal_cooling_device_stats_reinit(cdev);
1284
1285	list_for_each_entry(ti, &cdev->thermal_instances, cdev_node) {
1286		if (ti->upper == cdev->max_state)
1287			continue;
1288
1289		if (ti->upper < cdev->max_state) {
1290			if (ti->upper_no_limit)
1291				ti->upper = cdev->max_state;
1292
1293			continue;
1294		}
1295
1296		ti->upper = cdev->max_state;
1297		if (ti->lower > ti->upper)
1298			ti->lower = ti->upper;
1299
1300		if (ti->target == THERMAL_NO_TARGET)
1301			continue;
1302
1303		if (ti->target > ti->upper)
1304			ti->target = ti->upper;
 
 
 
 
 
1305	}
1306
1307	if (cdev->ops->get_cur_state(cdev, &state) || state > cdev->max_state)
1308		return;
1309
1310	thermal_cooling_device_stats_update(cdev, state);
1311}
1312EXPORT_SYMBOL_GPL(thermal_cooling_device_update);
1313
1314static void __thermal_zone_cdev_unbind(struct thermal_zone_device *tz,
1315				       struct thermal_cooling_device *cdev)
1316{
1317	struct thermal_trip_desc *td;
1318
1319	for_each_trip_desc(tz, td)
1320		thermal_unbind_cdev_from_trip(tz, td, cdev);
1321}
1322
1323static void thermal_zone_cdev_unbind(struct thermal_zone_device *tz,
1324				     struct thermal_cooling_device *cdev)
1325{
1326	guard(thermal_zone)(tz);
1327
1328	__thermal_zone_cdev_unbind(tz, cdev);
1329}
1330
1331static bool thermal_cooling_device_exit(struct thermal_cooling_device *cdev)
1332{
1333	struct thermal_zone_device *tz;
1334
1335	guard(mutex)(&thermal_list_lock);
1336
1337	if (!thermal_cooling_device_present(cdev))
1338		return false;
1339
1340	list_del(&cdev->node);
1341
1342	list_for_each_entry(tz, &thermal_tz_list, node)
1343		thermal_zone_cdev_unbind(tz, cdev);
1344
1345	return true;
1346}
1347
1348/**
1349 * thermal_cooling_device_unregister() - removes a thermal cooling device
1350 * @cdev: Thermal cooling device to remove.
1351 */
1352void thermal_cooling_device_unregister(struct thermal_cooling_device *cdev)
1353{
1354	if (!cdev)
1355		return;
1356
1357	thermal_debug_cdev_remove(cdev);
1358
1359	if (thermal_cooling_device_exit(cdev))
1360		device_unregister(&cdev->device);
1361}
1362EXPORT_SYMBOL_GPL(thermal_cooling_device_unregister);
1363
1364int thermal_zone_get_crit_temp(struct thermal_zone_device *tz, int *temp)
1365{
1366	const struct thermal_trip_desc *td;
1367	int ret = -EINVAL;
1368
1369	if (tz->ops.get_crit_temp)
1370		return tz->ops.get_crit_temp(tz, temp);
1371
1372	guard(thermal_zone)(tz);
 
1373
1374	for_each_trip_desc(tz, td) {
1375		const struct thermal_trip *trip = &td->trip;
1376
1377		if (trip->type == THERMAL_TRIP_CRITICAL) {
1378			*temp = trip->temperature;
1379			ret = 0;
1380			break;
 
 
1381		}
 
1382	}
1383
1384	return ret;
1385}
1386EXPORT_SYMBOL_GPL(thermal_zone_get_crit_temp);
1387
1388static void thermal_zone_device_check(struct work_struct *work)
1389{
1390	struct thermal_zone_device *tz = container_of(work, struct
1391						      thermal_zone_device,
1392						      poll_queue.work);
1393	thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
1394}
1395
1396static void thermal_zone_device_init(struct thermal_zone_device *tz)
1397{
1398	struct thermal_trip_desc *td, *next;
1399
1400	INIT_DELAYED_WORK(&tz->poll_queue, thermal_zone_device_check);
1401
1402	tz->temperature = THERMAL_TEMP_INIT;
1403	tz->passive = 0;
1404	tz->prev_low_trip = -INT_MAX;
1405	tz->prev_high_trip = INT_MAX;
1406	for_each_trip_desc(tz, td) {
1407		struct thermal_instance *instance;
1408
1409		list_for_each_entry(instance, &td->thermal_instances, trip_node)
1410			instance->initialized = false;
1411	}
1412	/*
1413	 * At this point, all valid trips need to be moved to trips_high so that
1414	 * mitigation can be started if the zone temperature is above them.
1415	 */
1416	list_for_each_entry_safe(td, next, &tz->trips_invalid, list_node) {
1417		if (td->trip.temperature != THERMAL_TEMP_INVALID)
1418			move_to_trips_high(tz, td);
1419	}
1420	/* The trips_reached list may not be empty during system resume. */
1421	list_for_each_entry_safe(td, next, &tz->trips_reached, list_node) {
1422		if (td->trip.temperature == THERMAL_TEMP_INVALID)
1423			move_to_trips_invalid(tz, td);
1424		else
1425			move_to_trips_high(tz, td);
1426	}
1427}
1428
1429static int thermal_zone_init_governor(struct thermal_zone_device *tz)
1430{
1431	struct thermal_governor *governor;
1432
1433	guard(mutex)(&thermal_governor_lock);
1434
1435	if (tz->tzp)
1436		governor = __find_governor(tz->tzp->governor_name);
1437	else
1438		governor = def_governor;
1439
1440	return thermal_set_governor(tz, governor);
1441}
1442
1443static void thermal_zone_init_complete(struct thermal_zone_device *tz)
1444{
1445	struct thermal_cooling_device *cdev;
1446
1447	guard(mutex)(&thermal_list_lock);
1448
1449	list_add_tail(&tz->node, &thermal_tz_list);
1450
1451	guard(thermal_zone)(tz);
1452
1453	/* Bind cooling devices for this zone. */
1454	list_for_each_entry(cdev, &thermal_cdev_list, node)
1455		__thermal_zone_cdev_bind(tz, cdev);
1456
1457	tz->state &= ~TZ_STATE_FLAG_INIT;
1458	/*
1459	 * If system suspend or resume is in progress at this point, the
1460	 * new thermal zone needs to be marked as suspended because
1461	 * thermal_pm_notify() has run already.
1462	 */
1463	if (thermal_pm_suspended)
1464		tz->state |= TZ_STATE_FLAG_SUSPENDED;
1465
1466	__thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
1467}
1468
1469/**
1470 * thermal_zone_device_register_with_trips() - register a new thermal zone device
1471 * @type:	the thermal zone device type
1472 * @trips:	a pointer to an array of thermal trips
1473 * @num_trips:	the number of trip points the thermal zone support
1474 * @devdata:	private device data
1475 * @ops:	standard thermal zone device callbacks
1476 * @tzp:	thermal zone platform parameters
1477 * @passive_delay: number of milliseconds to wait between polls when
1478 *		   performing passive cooling
1479 * @polling_delay: number of milliseconds to wait between polls when checking
1480 *		   whether trip points have been crossed (0 for interrupt
1481 *		   driven systems)
1482 *
1483 * This interface function adds a new thermal zone device (sensor) to
1484 * /sys/class/thermal folder as thermal_zone[0-*]. It tries to bind all the
1485 * thermal cooling devices registered at the same time.
1486 * thermal_zone_device_unregister() must be called when the device is no
1487 * longer needed. The passive cooling depends on the .get_trend() return value.
1488 *
1489 * Return: a pointer to the created struct thermal_zone_device or an
1490 * in case of error, an ERR_PTR. Caller must check return value with
1491 * IS_ERR*() helpers.
1492 */
1493struct thermal_zone_device *
1494thermal_zone_device_register_with_trips(const char *type,
1495					const struct thermal_trip *trips,
1496					int num_trips, void *devdata,
1497					const struct thermal_zone_device_ops *ops,
1498					const struct thermal_zone_params *tzp,
1499					unsigned int passive_delay,
1500					unsigned int polling_delay)
1501{
1502	const struct thermal_trip *trip = trips;
1503	struct thermal_zone_device *tz;
1504	struct thermal_trip_desc *td;
 
1505	int id;
1506	int result;
 
 
1507
1508	if (!type || strlen(type) == 0) {
1509		pr_err("No thermal zone type defined\n");
1510		return ERR_PTR(-EINVAL);
1511	}
1512
1513	if (strlen(type) >= THERMAL_NAME_LENGTH) {
1514		pr_err("Thermal zone name (%s) too long, should be under %d chars\n",
1515		       type, THERMAL_NAME_LENGTH);
1516		return ERR_PTR(-EINVAL);
1517	}
1518
1519	if (num_trips < 0) {
1520		pr_err("Incorrect number of thermal trips\n");
1521		return ERR_PTR(-EINVAL);
1522	}
1523
1524	if (!ops || !ops->get_temp) {
1525		pr_err("Thermal zone device ops not defined or invalid\n");
1526		return ERR_PTR(-EINVAL);
1527	}
1528
1529	if (num_trips > 0 && !trips)
1530		return ERR_PTR(-EINVAL);
1531
1532	if (polling_delay && passive_delay > polling_delay)
1533		return ERR_PTR(-EINVAL);
1534
1535	if (!thermal_class)
1536		return ERR_PTR(-ENODEV);
1537
1538	tz = kzalloc(struct_size(tz, trips, num_trips), GFP_KERNEL);
1539	if (!tz)
1540		return ERR_PTR(-ENOMEM);
1541
1542	if (tzp) {
1543		tz->tzp = kmemdup(tzp, sizeof(*tzp), GFP_KERNEL);
1544		if (!tz->tzp) {
1545			result = -ENOMEM;
1546			goto free_tz;
1547		}
1548	}
1549
1550	INIT_LIST_HEAD(&tz->node);
1551	INIT_LIST_HEAD(&tz->trips_high);
1552	INIT_LIST_HEAD(&tz->trips_reached);
1553	INIT_LIST_HEAD(&tz->trips_invalid);
1554	ida_init(&tz->ida);
1555	mutex_init(&tz->lock);
1556	init_completion(&tz->removal);
1557	init_completion(&tz->resume);
1558	id = ida_alloc(&thermal_tz_ida, GFP_KERNEL);
1559	if (id < 0) {
1560		result = id;
1561		goto free_tzp;
1562	}
1563
1564	tz->id = id;
1565	strscpy(tz->type, type, sizeof(tz->type));
1566
1567	tz->ops = *ops;
1568	if (!tz->ops.critical)
1569		tz->ops.critical = thermal_zone_device_critical;
1570
1571	tz->device.class = thermal_class;
1572	tz->devdata = devdata;
1573	tz->num_trips = num_trips;
1574	for_each_trip_desc(tz, td) {
1575		td->trip = *trip++;
1576		INIT_LIST_HEAD(&td->thermal_instances);
1577		INIT_LIST_HEAD(&td->list_node);
1578		/*
1579		 * Mark all thresholds as invalid to start with even though
1580		 * this only matters for the trips that start as invalid and
1581		 * become valid later.
1582		 */
1583		move_to_trips_invalid(tz, td);
1584	}
1585
1586	tz->polling_delay_jiffies = msecs_to_jiffies(polling_delay);
1587	tz->passive_delay_jiffies = msecs_to_jiffies(passive_delay);
1588	tz->recheck_delay_jiffies = THERMAL_RECHECK_DELAY;
1589
1590	tz->state = TZ_STATE_FLAG_INIT;
1591
1592	/* sys I/F */
1593	/* Add nodes that are always present via .groups */
1594	result = thermal_zone_create_device_groups(tz);
1595	if (result)
1596		goto remove_id;
1597
1598	result = dev_set_name(&tz->device, "thermal_zone%d", tz->id);
1599	if (result) {
1600		thermal_zone_destroy_device_groups(tz);
1601		goto remove_id;
1602	}
1603	thermal_zone_device_init(tz);
1604	result = device_register(&tz->device);
1605	if (result)
1606		goto release_device;
1607
1608	result = thermal_zone_init_governor(tz);
1609	if (result)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1610		goto unregister;
 
 
 
1611
1612	if (!tz->tzp || !tz->tzp->no_hwmon) {
1613		result = thermal_add_hwmon_sysfs(tz);
1614		if (result)
1615			goto unregister;
1616	}
1617
1618	result = thermal_thresholds_init(tz);
1619	if (result)
1620		goto remove_hwmon;
1621
1622	thermal_zone_init_complete(tz);
 
1623
1624	thermal_notify_tz_create(tz);
1625
1626	thermal_debug_tz_add(tz);
 
 
 
1627
1628	return tz;
1629
1630remove_hwmon:
1631	thermal_remove_hwmon_sysfs(tz);
1632unregister:
1633	device_del(&tz->device);
1634release_device:
1635	put_device(&tz->device);
 
1636remove_id:
1637	ida_free(&thermal_tz_ida, id);
1638free_tzp:
1639	kfree(tz->tzp);
1640free_tz:
1641	kfree(tz);
1642	return ERR_PTR(result);
1643}
1644EXPORT_SYMBOL_GPL(thermal_zone_device_register_with_trips);
1645
1646struct thermal_zone_device *thermal_tripless_zone_device_register(
1647					const char *type,
1648					void *devdata,
1649					const struct thermal_zone_device_ops *ops,
1650					const struct thermal_zone_params *tzp)
1651{
1652	return thermal_zone_device_register_with_trips(type, NULL, 0, devdata,
1653						       ops, tzp, 0, 0);
1654}
1655EXPORT_SYMBOL_GPL(thermal_tripless_zone_device_register);
1656
1657void *thermal_zone_device_priv(struct thermal_zone_device *tzd)
1658{
1659	return tzd->devdata;
1660}
1661EXPORT_SYMBOL_GPL(thermal_zone_device_priv);
1662
1663const char *thermal_zone_device_type(struct thermal_zone_device *tzd)
1664{
1665	return tzd->type;
1666}
1667EXPORT_SYMBOL_GPL(thermal_zone_device_type);
1668
1669int thermal_zone_device_id(struct thermal_zone_device *tzd)
1670{
1671	return tzd->id;
1672}
1673EXPORT_SYMBOL_GPL(thermal_zone_device_id);
1674
1675struct device *thermal_zone_device(struct thermal_zone_device *tzd)
1676{
1677	return &tzd->device;
1678}
1679EXPORT_SYMBOL_GPL(thermal_zone_device);
1680
1681static bool thermal_zone_exit(struct thermal_zone_device *tz)
1682{
1683	struct thermal_cooling_device *cdev;
1684
1685	guard(mutex)(&thermal_list_lock);
1686
1687	if (list_empty(&tz->node))
1688		return false;
1689
1690	guard(thermal_zone)(tz);
1691
1692	tz->state |= TZ_STATE_FLAG_EXIT;
1693	list_del_init(&tz->node);
1694
1695	/* Unbind all cdevs associated with this thermal zone. */
1696	list_for_each_entry(cdev, &thermal_cdev_list, node)
1697		__thermal_zone_cdev_unbind(tz, cdev);
1698
1699	return true;
1700}
1701
1702/**
1703 * thermal_zone_device_unregister - removes the registered thermal zone device
1704 * @tz: the thermal zone device to remove
1705 */
1706void thermal_zone_device_unregister(struct thermal_zone_device *tz)
1707{
 
 
 
 
 
1708	if (!tz)
1709		return;
1710
1711	thermal_debug_tz_remove(tz);
1712
1713	if (!thermal_zone_exit(tz))
 
 
 
 
 
 
1714		return;
 
 
1715
1716	cancel_delayed_work_sync(&tz->poll_queue);
 
 
 
 
 
1717
1718	thermal_set_governor(tz, NULL);
 
1719
1720	thermal_thresholds_exit(tz);
1721	thermal_remove_hwmon_sysfs(tz);
1722	ida_free(&thermal_tz_ida, tz->id);
1723	ida_destroy(&tz->ida);
 
 
 
1724
1725	device_del(&tz->device);
1726	put_device(&tz->device);
1727
1728	thermal_notify_tz_delete(tz);
1729
1730	wait_for_completion(&tz->removal);
1731	kfree(tz->tzp);
1732	kfree(tz);
 
 
 
 
1733}
1734EXPORT_SYMBOL_GPL(thermal_zone_device_unregister);
1735
1736/**
1737 * thermal_zone_get_zone_by_name() - search for a zone and returns its ref
1738 * @name: thermal zone name to fetch the temperature
1739 *
1740 * When only one zone is found with the passed name, returns a reference to it.
1741 *
1742 * Return: On success returns a reference to an unique thermal zone with
1743 * matching name equals to @name, an ERR_PTR otherwise (-EINVAL for invalid
1744 * paramenters, -ENODEV for not found and -EEXIST for multiple matches).
1745 */
1746struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name)
1747{
1748	struct thermal_zone_device *pos = NULL, *ref = ERR_PTR(-EINVAL);
1749	unsigned int found = 0;
1750
1751	if (!name)
1752		return ERR_PTR(-EINVAL);
1753
1754	guard(mutex)(&thermal_list_lock);
1755
 
1756	list_for_each_entry(pos, &thermal_tz_list, node)
1757		if (!strncasecmp(name, pos->type, THERMAL_NAME_LENGTH)) {
1758			found++;
1759			ref = pos;
1760		}
 
1761
1762	if (!found)
1763		return ERR_PTR(-ENODEV);
1764
1765	/* Success only when one zone is found. */
1766	if (found > 1)
1767		return ERR_PTR(-EEXIST);
1768
 
1769	return ref;
1770}
1771EXPORT_SYMBOL_GPL(thermal_zone_get_zone_by_name);
1772
1773static void thermal_zone_device_resume(struct work_struct *work)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1774{
1775	struct thermal_zone_device *tz;
 
 
 
 
 
 
1776
1777	tz = container_of(work, struct thermal_zone_device, poll_queue.work);
 
1778
1779	guard(thermal_zone)(tz);
 
 
1780
1781	tz->state &= ~(TZ_STATE_FLAG_SUSPENDED | TZ_STATE_FLAG_RESUMING);
 
 
1782
1783	thermal_debug_tz_resume(tz);
1784	thermal_zone_device_init(tz);
1785	thermal_governor_update_tz(tz, THERMAL_TZ_RESUME);
1786	__thermal_zone_device_update(tz, THERMAL_TZ_RESUME);
 
 
 
 
1787
1788	complete(&tz->resume);
1789}
 
1790
1791static void thermal_zone_pm_prepare(struct thermal_zone_device *tz)
1792{
1793	guard(thermal_zone)(tz);
 
1794
1795	if (tz->state & TZ_STATE_FLAG_RESUMING) {
1796		/*
1797		 * thermal_zone_device_resume() queued up for this zone has not
1798		 * acquired the lock yet, so release it to let the function run
1799		 * and wait util it has done the work.
1800		 */
1801		scoped_guard(thermal_zone_reverse, tz) {
1802			wait_for_completion(&tz->resume);
1803		}
1804	}
1805
1806	tz->state |= TZ_STATE_FLAG_SUSPENDED;
1807}
1808
1809static void thermal_pm_notify_prepare(void)
1810{
1811	struct thermal_zone_device *tz;
1812
1813	guard(mutex)(&thermal_list_lock);
 
1814
1815	thermal_pm_suspended = true;
 
 
 
1816
1817	list_for_each_entry(tz, &thermal_tz_list, node)
1818		thermal_zone_pm_prepare(tz);
1819}
 
1820
1821static void thermal_zone_pm_complete(struct thermal_zone_device *tz)
1822{
1823	guard(thermal_zone)(tz);
1824
1825	cancel_delayed_work(&tz->poll_queue);
1826
1827	reinit_completion(&tz->resume);
1828	tz->state |= TZ_STATE_FLAG_RESUMING;
1829
1830	/*
1831	 * Replace the work function with the resume one, which will restore the
1832	 * original work function and schedule the polling work if needed.
1833	 */
1834	INIT_DELAYED_WORK(&tz->poll_queue, thermal_zone_device_resume);
1835	/* Queue up the work without a delay. */
1836	mod_delayed_work(system_freezable_power_efficient_wq, &tz->poll_queue, 0);
1837}
1838
1839static void thermal_pm_notify_complete(void)
1840{
1841	struct thermal_zone_device *tz;
1842
1843	guard(mutex)(&thermal_list_lock);
1844
1845	thermal_pm_suspended = false;
1846
1847	list_for_each_entry(tz, &thermal_tz_list, node)
1848		thermal_zone_pm_complete(tz);
1849}
 
 
 
 
1850
1851static int thermal_pm_notify(struct notifier_block *nb,
1852			     unsigned long mode, void *_unused)
1853{
 
 
 
1854	switch (mode) {
1855	case PM_HIBERNATION_PREPARE:
1856	case PM_RESTORE_PREPARE:
1857	case PM_SUSPEND_PREPARE:
1858		thermal_pm_notify_prepare();
1859		break;
1860	case PM_POST_HIBERNATION:
1861	case PM_POST_RESTORE:
1862	case PM_POST_SUSPEND:
1863		thermal_pm_notify_complete();
 
 
 
 
 
 
 
 
 
 
 
 
1864		break;
1865	default:
1866		break;
1867	}
1868	return 0;
1869}
1870
1871static struct notifier_block thermal_pm_nb = {
1872	.notifier_call = thermal_pm_notify,
1873	/*
1874	 * Run at the lowest priority to avoid interference between the thermal
1875	 * zone resume work items spawned by thermal_pm_notify() and the other
1876	 * PM notifiers.
1877	 */
1878	.priority = INT_MIN,
1879};
1880
1881static int __init thermal_init(void)
1882{
1883	int result;
1884
1885	thermal_debug_init();
1886
1887	result = thermal_netlink_init();
1888	if (result)
1889		goto error;
1890
1891	result = thermal_register_governors();
1892	if (result)
1893		goto unregister_netlink;
1894
1895	thermal_class = kzalloc(sizeof(*thermal_class), GFP_KERNEL);
1896	if (!thermal_class) {
1897		result = -ENOMEM;
1898		goto unregister_governors;
1899	}
1900
1901	thermal_class->name = "thermal";
1902	thermal_class->dev_release = thermal_release;
 
1903
1904	result = class_register(thermal_class);
1905	if (result) {
1906		kfree(thermal_class);
1907		thermal_class = NULL;
1908		goto unregister_governors;
1909	}
1910
1911	result = register_pm_notifier(&thermal_pm_nb);
1912	if (result)
1913		pr_warn("Thermal: Can not register suspend notifier, return %d\n",
1914			result);
1915
1916	return 0;
1917
 
 
 
 
1918unregister_governors:
1919	thermal_unregister_governors();
1920unregister_netlink:
1921	thermal_netlink_exit();
1922error:
 
 
1923	mutex_destroy(&thermal_list_lock);
1924	mutex_destroy(&thermal_governor_lock);
 
1925	return result;
1926}
1927postcore_initcall(thermal_init);