drivers/thermal/thermal_sysfs.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  thermal.c - sysfs interface of thermal devices
   4  *
   5  *  Copyright (C) 2016 Eduardo Valentin <edubezval@gmail.com>
   6  *
   7  *  Highly based on original thermal_core.c
   8  *  Copyright (C) 2008 Intel Corp
   9  *  Copyright (C) 2008 Zhang Rui <rui.zhang@intel.com>
  10  *  Copyright (C) 2008 Sujith Thomas <sujith.thomas@intel.com>
  11  */
  12
  13 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  14
  15 #include <linux/sysfs.h>
  16 #include <linux/device.h>
  17 #include <linux/err.h>
  18 #include <linux/slab.h>
  19 #include <linux/string.h>
  20 #include <linux/jiffies.h>
  21
  22 #include "thermal_core.h"
  23
  24 /* sys I/F for thermal zone */
  25
  26 static ssize_t
  27 type_show(struct device *dev, struct device_attribute *attr, char *buf)
  28 {
  29         struct thermal_zone_device *tz = to_thermal_zone(dev);
  30
  31         return sprintf(buf, "%s\n", tz->type);
  32 }
  33
  34 static ssize_t
  35 temp_show(struct device *dev, struct device_attribute *attr, char *buf)
  36 {
  37         struct thermal_zone_device *tz = to_thermal_zone(dev);
  38         int temperature, ret;
  39
  40         ret = thermal_zone_get_temp(tz, &temperature);
  41
  42         if (ret)
  43                 return ret;
  44
  45         return sprintf(buf, "%d\n", temperature);
  46 }
  47
  48 static ssize_t
  49 mode_show(struct device *dev, struct device_attribute *attr, char *buf)
  50 {
  51         struct thermal_zone_device *tz = to_thermal_zone(dev);
  52         int enabled;
  53
  54         mutex_lock(&tz->lock);
  55         enabled = thermal_zone_device_is_enabled(tz);
  56         mutex_unlock(&tz->lock);
  57
  58         return sprintf(buf, "%s\n", enabled ? "enabled" : "disabled");
  59 }
  60
  61 static ssize_t
  62 mode_store(struct device *dev, struct device_attribute *attr,
  63            const char *buf, size_t count)
  64 {
  65         struct thermal_zone_device *tz = to_thermal_zone(dev);
  66         int result;
  67
  68         if (!strncmp(buf, "enabled", sizeof("enabled") - 1))
  69                 result = thermal_zone_device_enable(tz);
  70         else if (!strncmp(buf, "disabled", sizeof("disabled") - 1))
  71                 result = thermal_zone_device_disable(tz);
  72         else
  73                 result = -EINVAL;
  74
  75         if (result)
  76                 return result;
  77
  78         return count;
  79 }
  80
  81 static ssize_t
  82 trip_point_type_show(struct device *dev, struct device_attribute *attr,
  83                      char *buf)
  84 {
  85         struct thermal_zone_device *tz = to_thermal_zone(dev);
  86         struct thermal_trip trip;
  87         int trip_id, result;
  88
  89         if (sscanf(attr->attr.name, "trip_point_%d_type", &trip_id) != 1)
  90                 return -EINVAL;
  91
  92         mutex_lock(&tz->lock);
  93
  94         if (device_is_registered(dev))
  95                 result = __thermal_zone_get_trip(tz, trip_id, &trip);
  96         else
  97                 result = -ENODEV;
  98
  99         mutex_unlock(&tz->lock);
 100
 101         if (result)
 102                 return result;
 103
 104         switch (trip.type) {
 105         case THERMAL_TRIP_CRITICAL:
 106                 return sprintf(buf, "critical\n");
 107         case THERMAL_TRIP_HOT:
 108                 return sprintf(buf, "hot\n");
 109         case THERMAL_TRIP_PASSIVE:
 110                 return sprintf(buf, "passive\n");
 111         case THERMAL_TRIP_ACTIVE:
 112                 return sprintf(buf, "active\n");
 113         default:
 114                 return sprintf(buf, "unknown\n");
 115         }
 116 }
 117
 118 static ssize_t
 119 trip_point_temp_store(struct device *dev, struct device_attribute *attr,
 120                       const char *buf, size_t count)
 121 {
 122         struct thermal_zone_device *tz = to_thermal_zone(dev);
 123         struct thermal_trip trip;
 124         int trip_id, ret;
 125
 126         if (sscanf(attr->attr.name, "trip_point_%d_temp", &trip_id) != 1)
 127                 return -EINVAL;
 128
 129         mutex_lock(&tz->lock);
 130
 131         if (!device_is_registered(dev)) {
 132                 ret = -ENODEV;
 133                 goto unlock;
 134         }
 135
 136         ret = __thermal_zone_get_trip(tz, trip_id, &trip);
 137         if (ret)
 138                 goto unlock;
 139
 140         ret = kstrtoint(buf, 10, &trip.temperature);
 141         if (ret)
 142                 goto unlock;
 143
 144         ret = thermal_zone_set_trip(tz, trip_id, &trip);
 145 unlock:
 146         mutex_unlock(&tz->lock);
 147
 148         return ret ? ret : count;
 149 }
 150
 151 static ssize_t
 152 trip_point_temp_show(struct device *dev, struct device_attribute *attr,
 153                      char *buf)
 154 {
 155         struct thermal_zone_device *tz = to_thermal_zone(dev);
 156         struct thermal_trip trip;
 157         int trip_id, ret;
 158
 159         if (sscanf(attr->attr.name, "trip_point_%d_temp", &trip_id) != 1)
 160                 return -EINVAL;
 161
 162         mutex_lock(&tz->lock);
 163
 164         if (device_is_registered(dev))
 165                 ret = __thermal_zone_get_trip(tz, trip_id, &trip);
 166         else
 167                 ret = -ENODEV;
 168
 169         mutex_unlock(&tz->lock);
 170
 171         if (ret)
 172                 return ret;
 173
 174         return sprintf(buf, "%d\n", trip.temperature);
 175 }
 176
 177 static ssize_t
 178 trip_point_hyst_store(struct device *dev, struct device_attribute *attr,
 179                       const char *buf, size_t count)
 180 {
 181         struct thermal_zone_device *tz = to_thermal_zone(dev);
 182         struct thermal_trip trip;
 183         int trip_id, ret;
 184
 185         if (sscanf(attr->attr.name, "trip_point_%d_hyst", &trip_id) != 1)
 186                 return -EINVAL;
 187
 188         if (kstrtoint(buf, 10, &trip.hysteresis))
 189                 return -EINVAL;
 190
 191         mutex_lock(&tz->lock);
 192
 193         if (!device_is_registered(dev)) {
 194                 ret = -ENODEV;
 195                 goto unlock;
 196         }
 197
 198         ret = __thermal_zone_get_trip(tz, trip_id, &trip);
 199         if (ret)
 200                 goto unlock;
 201
 202         ret = thermal_zone_set_trip(tz, trip_id, &trip);
 203 unlock:
 204         mutex_unlock(&tz->lock);
 205
 206         return ret ? ret : count;
 207 }
 208
 209 static ssize_t
 210 trip_point_hyst_show(struct device *dev, struct device_attribute *attr,
 211                      char *buf)
 212 {
 213         struct thermal_zone_device *tz = to_thermal_zone(dev);
 214         struct thermal_trip trip;
 215         int trip_id, ret;
 216
 217         if (sscanf(attr->attr.name, "trip_point_%d_hyst", &trip_id) != 1)
 218                 return -EINVAL;
 219
 220         mutex_lock(&tz->lock);
 221
 222         if (device_is_registered(dev))
 223                 ret = __thermal_zone_get_trip(tz, trip_id, &trip);
 224         else
 225                 ret = -ENODEV;
 226
 227         mutex_unlock(&tz->lock);
 228
 229         return ret ? ret : sprintf(buf, "%d\n", trip.hysteresis);
 230 }
 231
 232 static ssize_t
 233 policy_store(struct device *dev, struct device_attribute *attr,
 234              const char *buf, size_t count)
 235 {
 236         struct thermal_zone_device *tz = to_thermal_zone(dev);
 237         char name[THERMAL_NAME_LENGTH];
 238         int ret;
 239
 240         snprintf(name, sizeof(name), "%s", buf);
 241
 242         ret = thermal_zone_device_set_policy(tz, name);
 243         if (!ret)
 244                 ret = count;
 245
 246         return ret;
 247 }
 248
 249 static ssize_t
 250 policy_show(struct device *dev, struct device_attribute *devattr, char *buf)
 251 {
 252         struct thermal_zone_device *tz = to_thermal_zone(dev);
 253
 254         return sprintf(buf, "%s\n", tz->governor->name);
 255 }
 256
 257 static ssize_t
 258 available_policies_show(struct device *dev, struct device_attribute *devattr,
 259                         char *buf)
 260 {
 261         return thermal_build_list_of_policies(buf);
 262 }
 263
 264 #if (IS_ENABLED(CONFIG_THERMAL_EMULATION))
 265 static ssize_t
 266 emul_temp_store(struct device *dev, struct device_attribute *attr,
 267                 const char *buf, size_t count)
 268 {
 269         struct thermal_zone_device *tz = to_thermal_zone(dev);
 270         int ret = 0;
 271         int temperature;
 272
 273         if (kstrtoint(buf, 10, &temperature))
 274                 return -EINVAL;
 275
 276         mutex_lock(&tz->lock);
 277
 278         if (!device_is_registered(dev)) {
 279                 ret = -ENODEV;
 280                 goto unlock;
 281         }
 282
 283         if (!tz->ops->set_emul_temp)
 284                 tz->emul_temperature = temperature;
 285         else
 286                 ret = tz->ops->set_emul_temp(tz, temperature);
 287
 288         if (!ret)
 289                 __thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
 290
 291 unlock:
 292         mutex_unlock(&tz->lock);
 293
 294         return ret ? ret : count;
 295 }
 296 static DEVICE_ATTR_WO(emul_temp);
 297 #endif
 298
 299 static ssize_t
 300 sustainable_power_show(struct device *dev, struct device_attribute *devattr,
 301                        char *buf)
 302 {
 303         struct thermal_zone_device *tz = to_thermal_zone(dev);
 304
 305         if (tz->tzp)
 306                 return sprintf(buf, "%u\n", tz->tzp->sustainable_power);
 307         else
 308                 return -EIO;
 309 }
 310
 311 static ssize_t
 312 sustainable_power_store(struct device *dev, struct device_attribute *devattr,
 313                         const char *buf, size_t count)
 314 {
 315         struct thermal_zone_device *tz = to_thermal_zone(dev);
 316         u32 sustainable_power;
 317
 318         if (!tz->tzp)
 319                 return -EIO;
 320
 321         if (kstrtou32(buf, 10, &sustainable_power))
 322                 return -EINVAL;
 323
 324         tz->tzp->sustainable_power = sustainable_power;
 325
 326         return count;
 327 }
 328
 329 #define create_s32_tzp_attr(name)                                       \
 330         static ssize_t                                                  \
 331         name##_show(struct device *dev, struct device_attribute *devattr, \
 332                 char *buf)                                              \
 333         {                                                               \
 334         struct thermal_zone_device *tz = to_thermal_zone(dev);          \
 335                                                                         \
 336         if (tz->tzp)                                                    \
 337                 return sprintf(buf, "%d\n", tz->tzp->name);             \
 338         else                                                            \
 339                 return -EIO;                                            \
 340         }                                                               \
 341                                                                         \
 342         static ssize_t                                                  \
 343         name##_store(struct device *dev, struct device_attribute *devattr, \
 344                 const char *buf, size_t count)                          \
 345         {                                                               \
 346                 struct thermal_zone_device *tz = to_thermal_zone(dev);  \
 347                 s32 value;                                              \
 348                                                                         \
 349                 if (!tz->tzp)                                           \
 350                         return -EIO;                                    \
 351                                                                         \
 352                 if (kstrtos32(buf, 10, &value))                         \
 353                         return -EINVAL;                                 \
 354                                                                         \
 355                 tz->tzp->name = value;                                  \
 356                                                                         \
 357                 return count;                                           \
 358         }                                                               \
 359         static DEVICE_ATTR_RW(name)
 360
 361 create_s32_tzp_attr(k_po);
 362 create_s32_tzp_attr(k_pu);
 363 create_s32_tzp_attr(k_i);
 364 create_s32_tzp_attr(k_d);
 365 create_s32_tzp_attr(integral_cutoff);
 366 create_s32_tzp_attr(slope);
 367 create_s32_tzp_attr(offset);
 368 #undef create_s32_tzp_attr
 369
 370 /*
 371  * These are thermal zone device attributes that will always be present.
 372  * All the attributes created for tzp (create_s32_tzp_attr) also are always
 373  * present on the sysfs interface.
 374  */
 375 static DEVICE_ATTR_RO(type);
 376 static DEVICE_ATTR_RO(temp);
 377 static DEVICE_ATTR_RW(policy);
 378 static DEVICE_ATTR_RO(available_policies);
 379 static DEVICE_ATTR_RW(sustainable_power);
 380
 381 /* These thermal zone device attributes are created based on conditions */
 382 static DEVICE_ATTR_RW(mode);
 383
 384 /* These attributes are unconditionally added to a thermal zone */
 385 static struct attribute *thermal_zone_dev_attrs[] = {
 386         &dev_attr_type.attr,
 387         &dev_attr_temp.attr,
 388 #if (IS_ENABLED(CONFIG_THERMAL_EMULATION))
 389         &dev_attr_emul_temp.attr,
 390 #endif
 391         &dev_attr_policy.attr,
 392         &dev_attr_available_policies.attr,
 393         &dev_attr_sustainable_power.attr,
 394         &dev_attr_k_po.attr,
 395         &dev_attr_k_pu.attr,
 396         &dev_attr_k_i.attr,
 397         &dev_attr_k_d.attr,
 398         &dev_attr_integral_cutoff.attr,
 399         &dev_attr_slope.attr,
 400         &dev_attr_offset.attr,
 401         NULL,
 402 };
 403
 404 static const struct attribute_group thermal_zone_attribute_group = {
 405         .attrs = thermal_zone_dev_attrs,
 406 };
 407
 408 static struct attribute *thermal_zone_mode_attrs[] = {
 409         &dev_attr_mode.attr,
 410         NULL,
 411 };
 412
 413 static const struct attribute_group thermal_zone_mode_attribute_group = {
 414         .attrs = thermal_zone_mode_attrs,
 415 };
 416
 417 static const struct attribute_group *thermal_zone_attribute_groups[] = {
 418         &thermal_zone_attribute_group,
 419         &thermal_zone_mode_attribute_group,
 420         /* This is not NULL terminated as we create the group dynamically */
 421 };
 422
 423 /**
 424  * create_trip_attrs() - create attributes for trip points
 425  * @tz:         the thermal zone device
 426  * @mask:       Writeable trip point bitmap.
 427  *
 428  * helper function to instantiate sysfs entries for every trip
 429  * point and its properties of a struct thermal_zone_device.
 430  *
 431  * Return: 0 on success, the proper error value otherwise.
 432  */
 433 static int create_trip_attrs(struct thermal_zone_device *tz, int mask)
 434 {
 435         struct attribute **attrs;
 436         int indx;
 437
 438         /* This function works only for zones with at least one trip */
 439         if (tz->num_trips <= 0)
 440                 return -EINVAL;
 441
 442         tz->trip_type_attrs = kcalloc(tz->num_trips, sizeof(*tz->trip_type_attrs),
 443                                       GFP_KERNEL);
 444         if (!tz->trip_type_attrs)
 445                 return -ENOMEM;
 446
 447         tz->trip_temp_attrs = kcalloc(tz->num_trips, sizeof(*tz->trip_temp_attrs),
 448                                       GFP_KERNEL);
 449         if (!tz->trip_temp_attrs) {
 450                 kfree(tz->trip_type_attrs);
 451                 return -ENOMEM;
 452         }
 453
 454         tz->trip_hyst_attrs = kcalloc(tz->num_trips,
 455                                       sizeof(*tz->trip_hyst_attrs),
 456                                       GFP_KERNEL);
 457         if (!tz->trip_hyst_attrs) {
 458                 kfree(tz->trip_type_attrs);
 459                 kfree(tz->trip_temp_attrs);
 460                 return -ENOMEM;
 461         }
 462
 463         attrs = kcalloc(tz->num_trips * 3 + 1, sizeof(*attrs), GFP_KERNEL);
 464         if (!attrs) {
 465                 kfree(tz->trip_type_attrs);
 466                 kfree(tz->trip_temp_attrs);
 467                 kfree(tz->trip_hyst_attrs);
 468                 return -ENOMEM;
 469         }
 470
 471         for (indx = 0; indx < tz->num_trips; indx++) {
 472                 /* create trip type attribute */
 473                 snprintf(tz->trip_type_attrs[indx].name, THERMAL_NAME_LENGTH,
 474                          "trip_point_%d_type", indx);
 475
 476                 sysfs_attr_init(&tz->trip_type_attrs[indx].attr.attr);
 477                 tz->trip_type_attrs[indx].attr.attr.name =
 478                                                 tz->trip_type_attrs[indx].name;
 479                 tz->trip_type_attrs[indx].attr.attr.mode = S_IRUGO;
 480                 tz->trip_type_attrs[indx].attr.show = trip_point_type_show;
 481                 attrs[indx] = &tz->trip_type_attrs[indx].attr.attr;
 482
 483                 /* create trip temp attribute */
 484                 snprintf(tz->trip_temp_attrs[indx].name, THERMAL_NAME_LENGTH,
 485                          "trip_point_%d_temp", indx);
 486
 487                 sysfs_attr_init(&tz->trip_temp_attrs[indx].attr.attr);
 488                 tz->trip_temp_attrs[indx].attr.attr.name =
 489                                                 tz->trip_temp_attrs[indx].name;
 490                 tz->trip_temp_attrs[indx].attr.attr.mode = S_IRUGO;
 491                 tz->trip_temp_attrs[indx].attr.show = trip_point_temp_show;
 492                 if (IS_ENABLED(CONFIG_THERMAL_WRITABLE_TRIPS) &&
 493                     mask & (1 << indx)) {
 494                         tz->trip_temp_attrs[indx].attr.attr.mode |= S_IWUSR;
 495                         tz->trip_temp_attrs[indx].attr.store =
 496                                                         trip_point_temp_store;
 497                 }
 498                 attrs[indx + tz->num_trips] = &tz->trip_temp_attrs[indx].attr.attr;
 499
 500                 snprintf(tz->trip_hyst_attrs[indx].name, THERMAL_NAME_LENGTH,
 501                          "trip_point_%d_hyst", indx);
 502
 503                 sysfs_attr_init(&tz->trip_hyst_attrs[indx].attr.attr);
 504                 tz->trip_hyst_attrs[indx].attr.attr.name =
 505                                         tz->trip_hyst_attrs[indx].name;
 506                 tz->trip_hyst_attrs[indx].attr.attr.mode = S_IRUGO;
 507                 tz->trip_hyst_attrs[indx].attr.show = trip_point_hyst_show;
 508                 if (tz->ops->set_trip_hyst) {
 509                         tz->trip_hyst_attrs[indx].attr.attr.mode |= S_IWUSR;
 510                         tz->trip_hyst_attrs[indx].attr.store =
 511                                         trip_point_hyst_store;
 512                 }
 513                 attrs[indx + tz->num_trips * 2] =
 514                                         &tz->trip_hyst_attrs[indx].attr.attr;
 515         }
 516         attrs[tz->num_trips * 3] = NULL;
 517
 518         tz->trips_attribute_group.attrs = attrs;
 519
 520         return 0;
 521 }
 522
 523 /**
 524  * destroy_trip_attrs() - destroy attributes for trip points
 525  * @tz:         the thermal zone device
 526  *
 527  * helper function to free resources allocated by create_trip_attrs()
 528  */
 529 static void destroy_trip_attrs(struct thermal_zone_device *tz)
 530 {
 531         if (!tz)
 532                 return;
 533
 534         kfree(tz->trip_type_attrs);
 535         kfree(tz->trip_temp_attrs);
 536         kfree(tz->trip_hyst_attrs);
 537         kfree(tz->trips_attribute_group.attrs);
 538 }
 539
 540 int thermal_zone_create_device_groups(struct thermal_zone_device *tz,
 541                                       int mask)
 542 {
 543         const struct attribute_group **groups;
 544         int i, size, result;
 545
 546         /* we need one extra for trips and the NULL to terminate the array */
 547         size = ARRAY_SIZE(thermal_zone_attribute_groups) + 2;
 548         /* This also takes care of API requirement to be NULL terminated */
 549         groups = kcalloc(size, sizeof(*groups), GFP_KERNEL);
 550         if (!groups)
 551                 return -ENOMEM;
 552
 553         for (i = 0; i < size - 2; i++)
 554                 groups[i] = thermal_zone_attribute_groups[i];
 555
 556         if (tz->num_trips) {
 557                 result = create_trip_attrs(tz, mask);
 558                 if (result) {
 559                         kfree(groups);
 560
 561                         return result;
 562                 }
 563
 564                 groups[size - 2] = &tz->trips_attribute_group;
 565         }
 566
 567         tz->device.groups = groups;
 568
 569         return 0;
 570 }
 571
 572 void thermal_zone_destroy_device_groups(struct thermal_zone_device *tz)
 573 {
 574         if (!tz)
 575                 return;
 576
 577         if (tz->num_trips)
 578                 destroy_trip_attrs(tz);
 579
 580         kfree(tz->device.groups);
 581 }
 582
 583 /* sys I/F for cooling device */
 584 static ssize_t
 585 cdev_type_show(struct device *dev, struct device_attribute *attr, char *buf)
 586 {
 587         struct thermal_cooling_device *cdev = to_cooling_device(dev);
 588
 589         return sprintf(buf, "%s\n", cdev->type);
 590 }
 591
 592 static ssize_t max_state_show(struct device *dev, struct device_attribute *attr,
 593                               char *buf)
 594 {
 595         struct thermal_cooling_device *cdev = to_cooling_device(dev);
 596
 597         return sprintf(buf, "%ld\n", cdev->max_state);
 598 }
 599
 600 static ssize_t cur_state_show(struct device *dev, struct device_attribute *attr,
 601                               char *buf)
 602 {
 603         struct thermal_cooling_device *cdev = to_cooling_device(dev);
 604         unsigned long state;
 605         int ret;
 606
 607         ret = cdev->ops->get_cur_state(cdev, &state);
 608         if (ret)
 609                 return ret;
 610         return sprintf(buf, "%ld\n", state);
 611 }
 612
 613 static ssize_t
 614 cur_state_store(struct device *dev, struct device_attribute *attr,
 615                 const char *buf, size_t count)
 616 {
 617         struct thermal_cooling_device *cdev = to_cooling_device(dev);
 618         unsigned long state;
 619         int result;
 620
 621         if (sscanf(buf, "%ld\n", &state) != 1)
 622                 return -EINVAL;
 623
 624         if ((long)state < 0)
 625                 return -EINVAL;
 626
 627         /* Requested state should be less than max_state + 1 */
 628         if (state > cdev->max_state)
 629                 return -EINVAL;
 630
 631         mutex_lock(&cdev->lock);
 632
 633         result = cdev->ops->set_cur_state(cdev, state);
 634         if (!result)
 635                 thermal_cooling_device_stats_update(cdev, state);
 636
 637         mutex_unlock(&cdev->lock);
 638         return result ? result : count;
 639 }
 640
 641 static struct device_attribute
 642 dev_attr_cdev_type = __ATTR(type, 0444, cdev_type_show, NULL);
 643 static DEVICE_ATTR_RO(max_state);
 644 static DEVICE_ATTR_RW(cur_state);
 645
 646 static struct attribute *cooling_device_attrs[] = {
 647         &dev_attr_cdev_type.attr,
 648         &dev_attr_max_state.attr,
 649         &dev_attr_cur_state.attr,
 650         NULL,
 651 };
 652
 653 static const struct attribute_group cooling_device_attr_group = {
 654         .attrs = cooling_device_attrs,
 655 };
 656
 657 static const struct attribute_group *cooling_device_attr_groups[] = {
 658         &cooling_device_attr_group,
 659         NULL, /* Space allocated for cooling_device_stats_attr_group */
 660         NULL,
 661 };
 662
 663 #ifdef CONFIG_THERMAL_STATISTICS
 664 struct cooling_dev_stats {
 665         spinlock_t lock;
 666         unsigned int total_trans;
 667         unsigned long state;
 668         ktime_t last_time;
 669         ktime_t *time_in_state;
 670         unsigned int *trans_table;
 671 };
 672
 673 static void update_time_in_state(struct cooling_dev_stats *stats)
 674 {
 675         ktime_t now = ktime_get(), delta;
 676
 677         delta = ktime_sub(now, stats->last_time);
 678         stats->time_in_state[stats->state] =
 679                 ktime_add(stats->time_in_state[stats->state], delta);
 680         stats->last_time = now;
 681 }
 682
 683 void thermal_cooling_device_stats_update(struct thermal_cooling_device *cdev,
 684                                          unsigned long new_state)
 685 {
 686         struct cooling_dev_stats *stats = cdev->stats;
 687
 688         lockdep_assert_held(&cdev->lock);
 689
 690         if (!stats)
 691                 return;
 692
 693         spin_lock(&stats->lock);
 694
 695         if (stats->state == new_state)
 696                 goto unlock;
 697
 698         update_time_in_state(stats);
 699         stats->trans_table[stats->state * (cdev->max_state + 1) + new_state]++;
 700         stats->state = new_state;
 701         stats->total_trans++;
 702
 703 unlock:
 704         spin_unlock(&stats->lock);
 705 }
 706
 707 static ssize_t total_trans_show(struct device *dev,
 708                                 struct device_attribute *attr, char *buf)
 709 {
 710         struct thermal_cooling_device *cdev = to_cooling_device(dev);
 711         struct cooling_dev_stats *stats;
 712         int ret = 0;
 713
 714         mutex_lock(&cdev->lock);
 715
 716         stats = cdev->stats;
 717         if (!stats)
 718                 goto unlock;
 719
 720         spin_lock(&stats->lock);
 721         ret = sprintf(buf, "%u\n", stats->total_trans);
 722         spin_unlock(&stats->lock);
 723
 724 unlock:
 725         mutex_unlock(&cdev->lock);
 726
 727         return ret;
 728 }
 729
 730 static ssize_t
 731 time_in_state_ms_show(struct device *dev, struct device_attribute *attr,
 732                       char *buf)
 733 {
 734         struct thermal_cooling_device *cdev = to_cooling_device(dev);
 735         struct cooling_dev_stats *stats;
 736         ssize_t len = 0;
 737         int i;
 738
 739         mutex_lock(&cdev->lock);
 740
 741         stats = cdev->stats;
 742         if (!stats)
 743                 goto unlock;
 744
 745         spin_lock(&stats->lock);
 746
 747         update_time_in_state(stats);
 748
 749         for (i = 0; i <= cdev->max_state; i++) {
 750                 len += sprintf(buf + len, "state%u\t%llu\n", i,
 751                                ktime_to_ms(stats->time_in_state[i]));
 752         }
 753         spin_unlock(&stats->lock);
 754
 755 unlock:
 756         mutex_unlock(&cdev->lock);
 757
 758         return len;
 759 }
 760
 761 static ssize_t
 762 reset_store(struct device *dev, struct device_attribute *attr, const char *buf,
 763             size_t count)
 764 {
 765         struct thermal_cooling_device *cdev = to_cooling_device(dev);
 766         struct cooling_dev_stats *stats;
 767         int i, states;
 768
 769         mutex_lock(&cdev->lock);
 770
 771         stats = cdev->stats;
 772         if (!stats)
 773                 goto unlock;
 774
 775         states = cdev->max_state + 1;
 776
 777         spin_lock(&stats->lock);
 778
 779         stats->total_trans = 0;
 780         stats->last_time = ktime_get();
 781         memset(stats->trans_table, 0,
 782                states * states * sizeof(*stats->trans_table));
 783
 784         for (i = 0; i < states; i++)
 785                 stats->time_in_state[i] = ktime_set(0, 0);
 786
 787         spin_unlock(&stats->lock);
 788
 789 unlock:
 790         mutex_unlock(&cdev->lock);
 791
 792         return count;
 793 }
 794
 795 static ssize_t trans_table_show(struct device *dev,
 796                                 struct device_attribute *attr, char *buf)
 797 {
 798         struct thermal_cooling_device *cdev = to_cooling_device(dev);
 799         struct cooling_dev_stats *stats;
 800         ssize_t len = 0;
 801         int i, j;
 802
 803         mutex_lock(&cdev->lock);
 804
 805         stats = cdev->stats;
 806         if (!stats) {
 807                 len = -ENODATA;
 808                 goto unlock;
 809         }
 810
 811         len += snprintf(buf + len, PAGE_SIZE - len, " From  :    To\n");
 812         len += snprintf(buf + len, PAGE_SIZE - len, "       : ");
 813         for (i = 0; i <= cdev->max_state; i++) {
 814                 if (len >= PAGE_SIZE)
 815                         break;
 816                 len += snprintf(buf + len, PAGE_SIZE - len, "state%2u  ", i);
 817         }
 818         if (len >= PAGE_SIZE) {
 819                 len = PAGE_SIZE;
 820                 goto unlock;
 821         }
 822
 823         len += snprintf(buf + len, PAGE_SIZE - len, "\n");
 824
 825         for (i = 0; i <= cdev->max_state; i++) {
 826                 if (len >= PAGE_SIZE)
 827                         break;
 828
 829                 len += snprintf(buf + len, PAGE_SIZE - len, "state%2u:", i);
 830
 831                 for (j = 0; j <= cdev->max_state; j++) {
 832                         if (len >= PAGE_SIZE)
 833                                 break;
 834                         len += snprintf(buf + len, PAGE_SIZE - len, "%8u ",
 835                                 stats->trans_table[i * (cdev->max_state + 1) + j]);
 836                 }
 837                 if (len >= PAGE_SIZE)
 838                         break;
 839                 len += snprintf(buf + len, PAGE_SIZE - len, "\n");
 840         }
 841
 842         if (len >= PAGE_SIZE) {
 843                 pr_warn_once("Thermal transition table exceeds PAGE_SIZE. Disabling\n");
 844                 len = -EFBIG;
 845         }
 846
 847 unlock:
 848         mutex_unlock(&cdev->lock);
 849
 850         return len;
 851 }
 852
 853 static DEVICE_ATTR_RO(total_trans);
 854 static DEVICE_ATTR_RO(time_in_state_ms);
 855 static DEVICE_ATTR_WO(reset);
 856 static DEVICE_ATTR_RO(trans_table);
 857
 858 static struct attribute *cooling_device_stats_attrs[] = {
 859         &dev_attr_total_trans.attr,
 860         &dev_attr_time_in_state_ms.attr,
 861         &dev_attr_reset.attr,
 862         &dev_attr_trans_table.attr,
 863         NULL
 864 };
 865
 866 static const struct attribute_group cooling_device_stats_attr_group = {
 867         .attrs = cooling_device_stats_attrs,
 868         .name = "stats"
 869 };
 870
 871 static void cooling_device_stats_setup(struct thermal_cooling_device *cdev)
 872 {
 873         const struct attribute_group *stats_attr_group = NULL;
 874         struct cooling_dev_stats *stats;
 875         /* Total number of states is highest state + 1 */
 876         unsigned long states = cdev->max_state + 1;
 877         int var;
 878
 879         var = sizeof(*stats);
 880         var += sizeof(*stats->time_in_state) * states;
 881         var += sizeof(*stats->trans_table) * states * states;
 882
 883         stats = kzalloc(var, GFP_KERNEL);
 884         if (!stats)
 885                 goto out;
 886
 887         stats->time_in_state = (ktime_t *)(stats + 1);
 888         stats->trans_table = (unsigned int *)(stats->time_in_state + states);
 889         cdev->stats = stats;
 890         stats->last_time = ktime_get();
 891
 892         spin_lock_init(&stats->lock);
 893
 894         stats_attr_group = &cooling_device_stats_attr_group;
 895
 896 out:
 897         /* Fill the empty slot left in cooling_device_attr_groups */
 898         var = ARRAY_SIZE(cooling_device_attr_groups) - 2;
 899         cooling_device_attr_groups[var] = stats_attr_group;
 900 }
 901
 902 static void cooling_device_stats_destroy(struct thermal_cooling_device *cdev)
 903 {
 904         kfree(cdev->stats);
 905         cdev->stats = NULL;
 906 }
 907
 908 #else
 909
 910 static inline void
 911 cooling_device_stats_setup(struct thermal_cooling_device *cdev) {}
 912 static inline void
 913 cooling_device_stats_destroy(struct thermal_cooling_device *cdev) {}
 914
 915 #endif /* CONFIG_THERMAL_STATISTICS */
 916
 917 void thermal_cooling_device_setup_sysfs(struct thermal_cooling_device *cdev)
 918 {
 919         cooling_device_stats_setup(cdev);
 920         cdev->device.groups = cooling_device_attr_groups;
 921 }
 922
 923 void thermal_cooling_device_destroy_sysfs(struct thermal_cooling_device *cdev)
 924 {
 925         cooling_device_stats_destroy(cdev);
 926 }
 927
 928 void thermal_cooling_device_stats_reinit(struct thermal_cooling_device *cdev)
 929 {
 930         lockdep_assert_held(&cdev->lock);
 931
 932         cooling_device_stats_destroy(cdev);
 933         cooling_device_stats_setup(cdev);
 934 }
 935
 936 /* these helper will be used only at the time of bindig */
 937 ssize_t
 938 trip_point_show(struct device *dev, struct device_attribute *attr, char *buf)
 939 {
 940         struct thermal_instance *instance;
 941
 942         instance =
 943             container_of(attr, struct thermal_instance, attr);
 944
 945         return sprintf(buf, "%d\n", instance->trip);
 946 }
 947
 948 ssize_t
 949 weight_show(struct device *dev, struct device_attribute *attr, char *buf)
 950 {
 951         struct thermal_instance *instance;
 952
 953         instance = container_of(attr, struct thermal_instance, weight_attr);
 954
 955         return sprintf(buf, "%d\n", instance->weight);
 956 }
 957
 958 ssize_t weight_store(struct device *dev, struct device_attribute *attr,
 959                      const char *buf, size_t count)
 960 {
 961         struct thermal_instance *instance;
 962         int ret, weight;
 963
 964         ret = kstrtoint(buf, 0, &weight);
 965         if (ret)
 966                 return ret;
 967
 968         instance = container_of(attr, struct thermal_instance, weight_attr);
 969         instance->weight = weight;
 970
 971         return count;
 972 }