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         mutex_lock(&tz->lock);
 189
 190         if (!device_is_registered(dev)) {
 191                 ret = -ENODEV;
 192                 goto unlock;
 193         }
 194
 195         ret = __thermal_zone_get_trip(tz, trip_id, &trip);
 196         if (ret)
 197                 goto unlock;
 198
 199         ret = kstrtoint(buf, 10, &trip.hysteresis);
 200         if (ret)
 201                 goto unlock;
 202
 203         ret = thermal_zone_set_trip(tz, trip_id, &trip);
 204 unlock:
 205         mutex_unlock(&tz->lock);
 206
 207         return ret ? ret : count;
 208 }
 209
 210 static ssize_t
 211 trip_point_hyst_show(struct device *dev, struct device_attribute *attr,
 212                      char *buf)
 213 {
 214         struct thermal_zone_device *tz = to_thermal_zone(dev);
 215         struct thermal_trip trip;
 216         int trip_id, ret;
 217
 218         if (sscanf(attr->attr.name, "trip_point_%d_hyst", &trip_id) != 1)
 219                 return -EINVAL;
 220
 221         mutex_lock(&tz->lock);
 222
 223         if (device_is_registered(dev))
 224                 ret = __thermal_zone_get_trip(tz, trip_id, &trip);
 225         else
 226                 ret = -ENODEV;
 227
 228         mutex_unlock(&tz->lock);
 229
 230         return ret ? ret : sprintf(buf, "%d\n", trip.hysteresis);
 231 }
 232
 233 static ssize_t
 234 policy_store(struct device *dev, struct device_attribute *attr,
 235              const char *buf, size_t count)
 236 {
 237         struct thermal_zone_device *tz = to_thermal_zone(dev);
 238         char name[THERMAL_NAME_LENGTH];
 239         int ret;
 240
 241         snprintf(name, sizeof(name), "%s", buf);
 242
 243         ret = thermal_zone_device_set_policy(tz, name);
 244         if (!ret)
 245                 ret = count;
 246
 247         return ret;
 248 }
 249
 250 static ssize_t
 251 policy_show(struct device *dev, struct device_attribute *devattr, char *buf)
 252 {
 253         struct thermal_zone_device *tz = to_thermal_zone(dev);
 254
 255         return sprintf(buf, "%s\n", tz->governor->name);
 256 }
 257
 258 static ssize_t
 259 available_policies_show(struct device *dev, struct device_attribute *devattr,
 260                         char *buf)
 261 {
 262         return thermal_build_list_of_policies(buf);
 263 }
 264
 265 #if (IS_ENABLED(CONFIG_THERMAL_EMULATION))
 266 static ssize_t
 267 emul_temp_store(struct device *dev, struct device_attribute *attr,
 268                 const char *buf, size_t count)
 269 {
 270         struct thermal_zone_device *tz = to_thermal_zone(dev);
 271         int ret = 0;
 272         int temperature;
 273
 274         if (kstrtoint(buf, 10, &temperature))
 275                 return -EINVAL;
 276
 277         mutex_lock(&tz->lock);
 278
 279         if (!device_is_registered(dev)) {
 280                 ret = -ENODEV;
 281                 goto unlock;
 282         }
 283
 284         if (!tz->ops->set_emul_temp)
 285                 tz->emul_temperature = temperature;
 286         else
 287                 ret = tz->ops->set_emul_temp(tz, temperature);
 288
 289         if (!ret)
 290                 __thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
 291
 292 unlock:
 293         mutex_unlock(&tz->lock);
 294
 295         return ret ? ret : count;
 296 }
 297 static DEVICE_ATTR_WO(emul_temp);
 298 #endif
 299
 300 static ssize_t
 301 sustainable_power_show(struct device *dev, struct device_attribute *devattr,
 302                        char *buf)
 303 {
 304         struct thermal_zone_device *tz = to_thermal_zone(dev);
 305
 306         if (tz->tzp)
 307                 return sprintf(buf, "%u\n", tz->tzp->sustainable_power);
 308         else
 309                 return -EIO;
 310 }
 311
 312 static ssize_t
 313 sustainable_power_store(struct device *dev, struct device_attribute *devattr,
 314                         const char *buf, size_t count)
 315 {
 316         struct thermal_zone_device *tz = to_thermal_zone(dev);
 317         u32 sustainable_power;
 318
 319         if (!tz->tzp)
 320                 return -EIO;
 321
 322         if (kstrtou32(buf, 10, &sustainable_power))
 323                 return -EINVAL;
 324
 325         tz->tzp->sustainable_power = sustainable_power;
 326
 327         return count;
 328 }
 329
 330 #define create_s32_tzp_attr(name)                                       \
 331         static ssize_t                                                  \
 332         name##_show(struct device *dev, struct device_attribute *devattr, \
 333                 char *buf)                                              \
 334         {                                                               \
 335         struct thermal_zone_device *tz = to_thermal_zone(dev);          \
 336                                                                         \
 337         if (tz->tzp)                                                    \
 338                 return sprintf(buf, "%d\n", tz->tzp->name);             \
 339         else                                                            \
 340                 return -EIO;                                            \
 341         }                                                               \
 342                                                                         \
 343         static ssize_t                                                  \
 344         name##_store(struct device *dev, struct device_attribute *devattr, \
 345                 const char *buf, size_t count)                          \
 346         {                                                               \
 347                 struct thermal_zone_device *tz = to_thermal_zone(dev);  \
 348                 s32 value;                                              \
 349                                                                         \
 350                 if (!tz->tzp)                                           \
 351                         return -EIO;                                    \
 352                                                                         \
 353                 if (kstrtos32(buf, 10, &value))                         \
 354                         return -EINVAL;                                 \
 355                                                                         \
 356                 tz->tzp->name = value;                                  \
 357                                                                         \
 358                 return count;                                           \
 359         }                                                               \
 360         static DEVICE_ATTR_RW(name)
 361
 362 create_s32_tzp_attr(k_po);
 363 create_s32_tzp_attr(k_pu);
 364 create_s32_tzp_attr(k_i);
 365 create_s32_tzp_attr(k_d);
 366 create_s32_tzp_attr(integral_cutoff);
 367 create_s32_tzp_attr(slope);
 368 create_s32_tzp_attr(offset);
 369 #undef create_s32_tzp_attr
 370
 371 /*
 372  * These are thermal zone device attributes that will always be present.
 373  * All the attributes created for tzp (create_s32_tzp_attr) also are always
 374  * present on the sysfs interface.
 375  */
 376 static DEVICE_ATTR_RO(type);
 377 static DEVICE_ATTR_RO(temp);
 378 static DEVICE_ATTR_RW(policy);
 379 static DEVICE_ATTR_RO(available_policies);
 380 static DEVICE_ATTR_RW(sustainable_power);
 381
 382 /* These thermal zone device attributes are created based on conditions */
 383 static DEVICE_ATTR_RW(mode);
 384
 385 /* These attributes are unconditionally added to a thermal zone */
 386 static struct attribute *thermal_zone_dev_attrs[] = {
 387         &dev_attr_type.attr,
 388         &dev_attr_temp.attr,
 389 #if (IS_ENABLED(CONFIG_THERMAL_EMULATION))
 390         &dev_attr_emul_temp.attr,
 391 #endif
 392         &dev_attr_policy.attr,
 393         &dev_attr_available_policies.attr,
 394         &dev_attr_sustainable_power.attr,
 395         &dev_attr_k_po.attr,
 396         &dev_attr_k_pu.attr,
 397         &dev_attr_k_i.attr,
 398         &dev_attr_k_d.attr,
 399         &dev_attr_integral_cutoff.attr,
 400         &dev_attr_slope.attr,
 401         &dev_attr_offset.attr,
 402         NULL,
 403 };
 404
 405 static const struct attribute_group thermal_zone_attribute_group = {
 406         .attrs = thermal_zone_dev_attrs,
 407 };
 408
 409 static struct attribute *thermal_zone_mode_attrs[] = {
 410         &dev_attr_mode.attr,
 411         NULL,
 412 };
 413
 414 static const struct attribute_group thermal_zone_mode_attribute_group = {
 415         .attrs = thermal_zone_mode_attrs,
 416 };
 417
 418 static const struct attribute_group *thermal_zone_attribute_groups[] = {
 419         &thermal_zone_attribute_group,
 420         &thermal_zone_mode_attribute_group,
 421         /* This is not NULL terminated as we create the group dynamically */
 422 };
 423
 424 /**
 425  * create_trip_attrs() - create attributes for trip points
 426  * @tz:         the thermal zone device
 427  * @mask:       Writeable trip point bitmap.
 428  *
 429  * helper function to instantiate sysfs entries for every trip
 430  * point and its properties of a struct thermal_zone_device.
 431  *
 432  * Return: 0 on success, the proper error value otherwise.
 433  */
 434 static int create_trip_attrs(struct thermal_zone_device *tz, int mask)
 435 {
 436         struct attribute **attrs;
 437         int indx;
 438
 439         /* This function works only for zones with at least one trip */
 440         if (tz->num_trips <= 0)
 441                 return -EINVAL;
 442
 443         tz->trip_type_attrs = kcalloc(tz->num_trips, sizeof(*tz->trip_type_attrs),
 444                                       GFP_KERNEL);
 445         if (!tz->trip_type_attrs)
 446                 return -ENOMEM;
 447
 448         tz->trip_temp_attrs = kcalloc(tz->num_trips, sizeof(*tz->trip_temp_attrs),
 449                                       GFP_KERNEL);
 450         if (!tz->trip_temp_attrs) {
 451                 kfree(tz->trip_type_attrs);
 452                 return -ENOMEM;
 453         }
 454
 455         tz->trip_hyst_attrs = kcalloc(tz->num_trips,
 456                                       sizeof(*tz->trip_hyst_attrs),
 457                                       GFP_KERNEL);
 458         if (!tz->trip_hyst_attrs) {
 459                 kfree(tz->trip_type_attrs);
 460                 kfree(tz->trip_temp_attrs);
 461                 return -ENOMEM;
 462         }
 463
 464         attrs = kcalloc(tz->num_trips * 3 + 1, sizeof(*attrs), GFP_KERNEL);
 465         if (!attrs) {
 466                 kfree(tz->trip_type_attrs);
 467                 kfree(tz->trip_temp_attrs);
 468                 kfree(tz->trip_hyst_attrs);
 469                 return -ENOMEM;
 470         }
 471
 472         for (indx = 0; indx < tz->num_trips; indx++) {
 473                 /* create trip type attribute */
 474                 snprintf(tz->trip_type_attrs[indx].name, THERMAL_NAME_LENGTH,
 475                          "trip_point_%d_type", indx);
 476
 477                 sysfs_attr_init(&tz->trip_type_attrs[indx].attr.attr);
 478                 tz->trip_type_attrs[indx].attr.attr.name =
 479                                                 tz->trip_type_attrs[indx].name;
 480                 tz->trip_type_attrs[indx].attr.attr.mode = S_IRUGO;
 481                 tz->trip_type_attrs[indx].attr.show = trip_point_type_show;
 482                 attrs[indx] = &tz->trip_type_attrs[indx].attr.attr;
 483
 484                 /* create trip temp attribute */
 485                 snprintf(tz->trip_temp_attrs[indx].name, THERMAL_NAME_LENGTH,
 486                          "trip_point_%d_temp", indx);
 487
 488                 sysfs_attr_init(&tz->trip_temp_attrs[indx].attr.attr);
 489                 tz->trip_temp_attrs[indx].attr.attr.name =
 490                                                 tz->trip_temp_attrs[indx].name;
 491                 tz->trip_temp_attrs[indx].attr.attr.mode = S_IRUGO;
 492                 tz->trip_temp_attrs[indx].attr.show = trip_point_temp_show;
 493                 if (IS_ENABLED(CONFIG_THERMAL_WRITABLE_TRIPS) &&
 494                     mask & (1 << indx)) {
 495                         tz->trip_temp_attrs[indx].attr.attr.mode |= S_IWUSR;
 496                         tz->trip_temp_attrs[indx].attr.store =
 497                                                         trip_point_temp_store;
 498                 }
 499                 attrs[indx + tz->num_trips] = &tz->trip_temp_attrs[indx].attr.attr;
 500
 501                 snprintf(tz->trip_hyst_attrs[indx].name, THERMAL_NAME_LENGTH,
 502                          "trip_point_%d_hyst", indx);
 503
 504                 sysfs_attr_init(&tz->trip_hyst_attrs[indx].attr.attr);
 505                 tz->trip_hyst_attrs[indx].attr.attr.name =
 506                                         tz->trip_hyst_attrs[indx].name;
 507                 tz->trip_hyst_attrs[indx].attr.attr.mode = S_IRUGO;
 508                 tz->trip_hyst_attrs[indx].attr.show = trip_point_hyst_show;
 509                 if (tz->ops->set_trip_hyst) {
 510                         tz->trip_hyst_attrs[indx].attr.attr.mode |= S_IWUSR;
 511                         tz->trip_hyst_attrs[indx].attr.store =
 512                                         trip_point_hyst_store;
 513                 }
 514                 attrs[indx + tz->num_trips * 2] =
 515                                         &tz->trip_hyst_attrs[indx].attr.attr;
 516         }
 517         attrs[tz->num_trips * 3] = NULL;
 518
 519         tz->trips_attribute_group.attrs = attrs;
 520
 521         return 0;
 522 }
 523
 524 /**
 525  * destroy_trip_attrs() - destroy attributes for trip points
 526  * @tz:         the thermal zone device
 527  *
 528  * helper function to free resources allocated by create_trip_attrs()
 529  */
 530 static void destroy_trip_attrs(struct thermal_zone_device *tz)
 531 {
 532         if (!tz)
 533                 return;
 534
 535         kfree(tz->trip_type_attrs);
 536         kfree(tz->trip_temp_attrs);
 537         kfree(tz->trip_hyst_attrs);
 538         kfree(tz->trips_attribute_group.attrs);
 539 }
 540
 541 int thermal_zone_create_device_groups(struct thermal_zone_device *tz,
 542                                       int mask)
 543 {
 544         const struct attribute_group **groups;
 545         int i, size, result;
 546
 547         /* we need one extra for trips and the NULL to terminate the array */
 548         size = ARRAY_SIZE(thermal_zone_attribute_groups) + 2;
 549         /* This also takes care of API requirement to be NULL terminated */
 550         groups = kcalloc(size, sizeof(*groups), GFP_KERNEL);
 551         if (!groups)
 552                 return -ENOMEM;
 553
 554         for (i = 0; i < size - 2; i++)
 555                 groups[i] = thermal_zone_attribute_groups[i];
 556
 557         if (tz->num_trips) {
 558                 result = create_trip_attrs(tz, mask);
 559                 if (result) {
 560                         kfree(groups);
 561
 562                         return result;
 563                 }
 564
 565                 groups[size - 2] = &tz->trips_attribute_group;
 566         }
 567
 568         tz->device.groups = groups;
 569
 570         return 0;
 571 }
 572
 573 void thermal_zone_destroy_device_groups(struct thermal_zone_device *tz)
 574 {
 575         if (!tz)
 576                 return;
 577
 578         if (tz->num_trips)
 579                 destroy_trip_attrs(tz);
 580
 581         kfree(tz->device.groups);
 582 }
 583
 584 /* sys I/F for cooling device */
 585 static ssize_t
 586 cdev_type_show(struct device *dev, struct device_attribute *attr, char *buf)
 587 {
 588         struct thermal_cooling_device *cdev = to_cooling_device(dev);
 589
 590         return sprintf(buf, "%s\n", cdev->type);
 591 }
 592
 593 static ssize_t max_state_show(struct device *dev, struct device_attribute *attr,
 594                               char *buf)
 595 {
 596         struct thermal_cooling_device *cdev = to_cooling_device(dev);
 597
 598         return sprintf(buf, "%ld\n", cdev->max_state);
 599 }
 600
 601 static ssize_t cur_state_show(struct device *dev, struct device_attribute *attr,
 602                               char *buf)
 603 {
 604         struct thermal_cooling_device *cdev = to_cooling_device(dev);
 605         unsigned long state;
 606         int ret;
 607
 608         ret = cdev->ops->get_cur_state(cdev, &state);
 609         if (ret)
 610                 return ret;
 611         return sprintf(buf, "%ld\n", state);
 612 }
 613
 614 static ssize_t
 615 cur_state_store(struct device *dev, struct device_attribute *attr,
 616                 const char *buf, size_t count)
 617 {
 618         struct thermal_cooling_device *cdev = to_cooling_device(dev);
 619         unsigned long state;
 620         int result;
 621
 622         if (sscanf(buf, "%ld\n", &state) != 1)
 623                 return -EINVAL;
 624
 625         if ((long)state < 0)
 626                 return -EINVAL;
 627
 628         /* Requested state should be less than max_state + 1 */
 629         if (state > cdev->max_state)
 630                 return -EINVAL;
 631
 632         mutex_lock(&cdev->lock);
 633
 634         result = cdev->ops->set_cur_state(cdev, state);
 635         if (!result)
 636                 thermal_cooling_device_stats_update(cdev, state);
 637
 638         mutex_unlock(&cdev->lock);
 639         return result ? result : count;
 640 }
 641
 642 static struct device_attribute
 643 dev_attr_cdev_type = __ATTR(type, 0444, cdev_type_show, NULL);
 644 static DEVICE_ATTR_RO(max_state);
 645 static DEVICE_ATTR_RW(cur_state);
 646
 647 static struct attribute *cooling_device_attrs[] = {
 648         &dev_attr_cdev_type.attr,
 649         &dev_attr_max_state.attr,
 650         &dev_attr_cur_state.attr,
 651         NULL,
 652 };
 653
 654 static const struct attribute_group cooling_device_attr_group = {
 655         .attrs = cooling_device_attrs,
 656 };
 657
 658 static const struct attribute_group *cooling_device_attr_groups[] = {
 659         &cooling_device_attr_group,
 660         NULL, /* Space allocated for cooling_device_stats_attr_group */
 661         NULL,
 662 };
 663
 664 #ifdef CONFIG_THERMAL_STATISTICS
 665 struct cooling_dev_stats {
 666         spinlock_t lock;
 667         unsigned int total_trans;
 668         unsigned long state;
 669         ktime_t last_time;
 670         ktime_t *time_in_state;
 671         unsigned int *trans_table;
 672 };
 673
 674 static void update_time_in_state(struct cooling_dev_stats *stats)
 675 {
 676         ktime_t now = ktime_get(), delta;
 677
 678         delta = ktime_sub(now, stats->last_time);
 679         stats->time_in_state[stats->state] =
 680                 ktime_add(stats->time_in_state[stats->state], delta);
 681         stats->last_time = now;
 682 }
 683
 684 void thermal_cooling_device_stats_update(struct thermal_cooling_device *cdev,
 685                                          unsigned long new_state)
 686 {
 687         struct cooling_dev_stats *stats = cdev->stats;
 688
 689         lockdep_assert_held(&cdev->lock);
 690
 691         if (!stats)
 692                 return;
 693
 694         spin_lock(&stats->lock);
 695
 696         if (stats->state == new_state)
 697                 goto unlock;
 698
 699         update_time_in_state(stats);
 700         stats->trans_table[stats->state * (cdev->max_state + 1) + new_state]++;
 701         stats->state = new_state;
 702         stats->total_trans++;
 703
 704 unlock:
 705         spin_unlock(&stats->lock);
 706 }
 707
 708 static ssize_t total_trans_show(struct device *dev,
 709                                 struct device_attribute *attr, char *buf)
 710 {
 711         struct thermal_cooling_device *cdev = to_cooling_device(dev);
 712         struct cooling_dev_stats *stats;
 713         int ret = 0;
 714
 715         mutex_lock(&cdev->lock);
 716
 717         stats = cdev->stats;
 718         if (!stats)
 719                 goto unlock;
 720
 721         spin_lock(&stats->lock);
 722         ret = sprintf(buf, "%u\n", stats->total_trans);
 723         spin_unlock(&stats->lock);
 724
 725 unlock:
 726         mutex_unlock(&cdev->lock);
 727
 728         return ret;
 729 }
 730
 731 static ssize_t
 732 time_in_state_ms_show(struct device *dev, struct device_attribute *attr,
 733                       char *buf)
 734 {
 735         struct thermal_cooling_device *cdev = to_cooling_device(dev);
 736         struct cooling_dev_stats *stats;
 737         ssize_t len = 0;
 738         int i;
 739
 740         mutex_lock(&cdev->lock);
 741
 742         stats = cdev->stats;
 743         if (!stats)
 744                 goto unlock;
 745
 746         spin_lock(&stats->lock);
 747
 748         update_time_in_state(stats);
 749
 750         for (i = 0; i <= cdev->max_state; i++) {
 751                 len += sprintf(buf + len, "state%u\t%llu\n", i,
 752                                ktime_to_ms(stats->time_in_state[i]));
 753         }
 754         spin_unlock(&stats->lock);
 755
 756 unlock:
 757         mutex_unlock(&cdev->lock);
 758
 759         return len;
 760 }
 761
 762 static ssize_t
 763 reset_store(struct device *dev, struct device_attribute *attr, const char *buf,
 764             size_t count)
 765 {
 766         struct thermal_cooling_device *cdev = to_cooling_device(dev);
 767         struct cooling_dev_stats *stats;
 768         int i, states;
 769
 770         mutex_lock(&cdev->lock);
 771
 772         stats = cdev->stats;
 773         if (!stats)
 774                 goto unlock;
 775
 776         states = cdev->max_state + 1;
 777
 778         spin_lock(&stats->lock);
 779
 780         stats->total_trans = 0;
 781         stats->last_time = ktime_get();
 782         memset(stats->trans_table, 0,
 783                states * states * sizeof(*stats->trans_table));
 784
 785         for (i = 0; i < states; i++)
 786                 stats->time_in_state[i] = ktime_set(0, 0);
 787
 788         spin_unlock(&stats->lock);
 789
 790 unlock:
 791         mutex_unlock(&cdev->lock);
 792
 793         return count;
 794 }
 795
 796 static ssize_t trans_table_show(struct device *dev,
 797                                 struct device_attribute *attr, char *buf)
 798 {
 799         struct thermal_cooling_device *cdev = to_cooling_device(dev);
 800         struct cooling_dev_stats *stats;
 801         ssize_t len = 0;
 802         int i, j;
 803
 804         mutex_lock(&cdev->lock);
 805
 806         stats = cdev->stats;
 807         if (!stats) {
 808                 len = -ENODATA;
 809                 goto unlock;
 810         }
 811
 812         len += snprintf(buf + len, PAGE_SIZE - len, " From  :    To\n");
 813         len += snprintf(buf + len, PAGE_SIZE - len, "       : ");
 814         for (i = 0; i <= cdev->max_state; i++) {
 815                 if (len >= PAGE_SIZE)
 816                         break;
 817                 len += snprintf(buf + len, PAGE_SIZE - len, "state%2u  ", i);
 818         }
 819         if (len >= PAGE_SIZE) {
 820                 len = PAGE_SIZE;
 821                 goto unlock;
 822         }
 823
 824         len += snprintf(buf + len, PAGE_SIZE - len, "\n");
 825
 826         for (i = 0; i <= cdev->max_state; i++) {
 827                 if (len >= PAGE_SIZE)
 828                         break;
 829
 830                 len += snprintf(buf + len, PAGE_SIZE - len, "state%2u:", i);
 831
 832                 for (j = 0; j <= cdev->max_state; j++) {
 833                         if (len >= PAGE_SIZE)
 834                                 break;
 835                         len += snprintf(buf + len, PAGE_SIZE - len, "%8u ",
 836                                 stats->trans_table[i * (cdev->max_state + 1) + j]);
 837                 }
 838                 if (len >= PAGE_SIZE)
 839                         break;
 840                 len += snprintf(buf + len, PAGE_SIZE - len, "\n");
 841         }
 842
 843         if (len >= PAGE_SIZE) {
 844                 pr_warn_once("Thermal transition table exceeds PAGE_SIZE. Disabling\n");
 845                 len = -EFBIG;
 846         }
 847
 848 unlock:
 849         mutex_unlock(&cdev->lock);
 850
 851         return len;
 852 }
 853
 854 static DEVICE_ATTR_RO(total_trans);
 855 static DEVICE_ATTR_RO(time_in_state_ms);
 856 static DEVICE_ATTR_WO(reset);
 857 static DEVICE_ATTR_RO(trans_table);
 858
 859 static struct attribute *cooling_device_stats_attrs[] = {
 860         &dev_attr_total_trans.attr,
 861         &dev_attr_time_in_state_ms.attr,
 862         &dev_attr_reset.attr,
 863         &dev_attr_trans_table.attr,
 864         NULL
 865 };
 866
 867 static const struct attribute_group cooling_device_stats_attr_group = {
 868         .attrs = cooling_device_stats_attrs,
 869         .name = "stats"
 870 };
 871
 872 static void cooling_device_stats_setup(struct thermal_cooling_device *cdev)
 873 {
 874         const struct attribute_group *stats_attr_group = NULL;
 875         struct cooling_dev_stats *stats;
 876         /* Total number of states is highest state + 1 */
 877         unsigned long states = cdev->max_state + 1;
 878         int var;
 879
 880         var = sizeof(*stats);
 881         var += sizeof(*stats->time_in_state) * states;
 882         var += sizeof(*stats->trans_table) * states * states;
 883
 884         stats = kzalloc(var, GFP_KERNEL);
 885         if (!stats)
 886                 goto out;
 887
 888         stats->time_in_state = (ktime_t *)(stats + 1);
 889         stats->trans_table = (unsigned int *)(stats->time_in_state + states);
 890         cdev->stats = stats;
 891         stats->last_time = ktime_get();
 892
 893         spin_lock_init(&stats->lock);
 894
 895         stats_attr_group = &cooling_device_stats_attr_group;
 896
 897 out:
 898         /* Fill the empty slot left in cooling_device_attr_groups */
 899         var = ARRAY_SIZE(cooling_device_attr_groups) - 2;
 900         cooling_device_attr_groups[var] = stats_attr_group;
 901 }
 902
 903 static void cooling_device_stats_destroy(struct thermal_cooling_device *cdev)
 904 {
 905         kfree(cdev->stats);
 906         cdev->stats = NULL;
 907 }
 908
 909 #else
 910
 911 static inline void
 912 cooling_device_stats_setup(struct thermal_cooling_device *cdev) {}
 913 static inline void
 914 cooling_device_stats_destroy(struct thermal_cooling_device *cdev) {}
 915
 916 #endif /* CONFIG_THERMAL_STATISTICS */
 917
 918 void thermal_cooling_device_setup_sysfs(struct thermal_cooling_device *cdev)
 919 {
 920         cooling_device_stats_setup(cdev);
 921         cdev->device.groups = cooling_device_attr_groups;
 922 }
 923
 924 void thermal_cooling_device_destroy_sysfs(struct thermal_cooling_device *cdev)
 925 {
 926         cooling_device_stats_destroy(cdev);
 927 }
 928
 929 void thermal_cooling_device_stats_reinit(struct thermal_cooling_device *cdev)
 930 {
 931         lockdep_assert_held(&cdev->lock);
 932
 933         cooling_device_stats_destroy(cdev);
 934         cooling_device_stats_setup(cdev);
 935 }
 936
 937 /* these helper will be used only at the time of bindig */
 938 ssize_t
 939 trip_point_show(struct device *dev, struct device_attribute *attr, char *buf)
 940 {
 941         struct thermal_instance *instance;
 942
 943         instance =
 944             container_of(attr, struct thermal_instance, attr);
 945
 946         return sprintf(buf, "%d\n", instance->trip);
 947 }
 948
 949 ssize_t
 950 weight_show(struct device *dev, struct device_attribute *attr, char *buf)
 951 {
 952         struct thermal_instance *instance;
 953
 954         instance = container_of(attr, struct thermal_instance, weight_attr);
 955
 956         return sprintf(buf, "%d\n", instance->weight);
 957 }
 958
 959 ssize_t weight_store(struct device *dev, struct device_attribute *attr,
 960                      const char *buf, size_t count)
 961 {
 962         struct thermal_instance *instance;
 963         int ret, weight;
 964
 965         ret = kstrtoint(buf, 0, &weight);
 966         if (ret)
 967                 return ret;
 968
 969         instance = container_of(attr, struct thermal_instance, weight_attr);
 970         instance->weight = weight;
 971
 972         return count;
 973 }