drivers/thermal/thermal_sysfs.c

   1 /*
   2  *  thermal.c - sysfs interface of thermal devices
   3  *
   4  *  Copyright (C) 2016 Eduardo Valentin <edubezval@gmail.com>
   5  *
   6  *  Highly based on original thermal_core.c
   7  *  Copyright (C) 2008 Intel Corp
   8  *  Copyright (C) 2008 Zhang Rui <rui.zhang@intel.com>
   9  *  Copyright (C) 2008 Sujith Thomas <sujith.thomas@intel.com>
  10  *
  11  *  This program is free software; you can redistribute it and/or modify
  12  *  it under the terms of the GNU General Public License as published by
  13  *  the Free Software Foundation; version 2 of the License.
  14  */
  15
  16 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  17
  18 #include <linux/sysfs.h>
  19 #include <linux/device.h>
  20 #include <linux/err.h>
  21 #include <linux/slab.h>
  22 #include <linux/string.h>
  23
  24 #include "thermal_core.h"
  25
  26 /* sys I/F for thermal zone */
  27
  28 static ssize_t
  29 type_show(struct device *dev, struct device_attribute *attr, char *buf)
  30 {
  31         struct thermal_zone_device *tz = to_thermal_zone(dev);
  32
  33         return sprintf(buf, "%s\n", tz->type);
  34 }
  35
  36 static ssize_t
  37 temp_show(struct device *dev, struct device_attribute *attr, char *buf)
  38 {
  39         struct thermal_zone_device *tz = to_thermal_zone(dev);
  40         int temperature, ret;
  41
  42         ret = thermal_zone_get_temp(tz, &temperature);
  43
  44         if (ret)
  45                 return ret;
  46
  47         return sprintf(buf, "%d\n", temperature);
  48 }
  49
  50 static ssize_t
  51 mode_show(struct device *dev, struct device_attribute *attr, char *buf)
  52 {
  53         struct thermal_zone_device *tz = to_thermal_zone(dev);
  54         enum thermal_device_mode mode;
  55         int result;
  56
  57         if (!tz->ops->get_mode)
  58                 return -EPERM;
  59
  60         result = tz->ops->get_mode(tz, &mode);
  61         if (result)
  62                 return result;
  63
  64         return sprintf(buf, "%s\n", mode == THERMAL_DEVICE_ENABLED ? "enabled"
  65                        : "disabled");
  66 }
  67
  68 static ssize_t
  69 mode_store(struct device *dev, struct device_attribute *attr,
  70            const char *buf, size_t count)
  71 {
  72         struct thermal_zone_device *tz = to_thermal_zone(dev);
  73         int result;
  74
  75         if (!tz->ops->set_mode)
  76                 return -EPERM;
  77
  78         if (!strncmp(buf, "enabled", sizeof("enabled") - 1))
  79                 result = tz->ops->set_mode(tz, THERMAL_DEVICE_ENABLED);
  80         else if (!strncmp(buf, "disabled", sizeof("disabled") - 1))
  81                 result = tz->ops->set_mode(tz, THERMAL_DEVICE_DISABLED);
  82         else
  83                 result = -EINVAL;
  84
  85         if (result)
  86                 return result;
  87
  88         return count;
  89 }
  90
  91 static ssize_t
  92 trip_point_type_show(struct device *dev, struct device_attribute *attr,
  93                      char *buf)
  94 {
  95         struct thermal_zone_device *tz = to_thermal_zone(dev);
  96         enum thermal_trip_type type;
  97         int trip, result;
  98
  99         if (!tz->ops->get_trip_type)
 100                 return -EPERM;
 101
 102         if (sscanf(attr->attr.name, "trip_point_%d_type", &trip) != 1)
 103                 return -EINVAL;
 104
 105         result = tz->ops->get_trip_type(tz, trip, &type);
 106         if (result)
 107                 return result;
 108
 109         switch (type) {
 110         case THERMAL_TRIP_CRITICAL:
 111                 return sprintf(buf, "critical\n");
 112         case THERMAL_TRIP_HOT:
 113                 return sprintf(buf, "hot\n");
 114         case THERMAL_TRIP_PASSIVE:
 115                 return sprintf(buf, "passive\n");
 116         case THERMAL_TRIP_ACTIVE:
 117                 return sprintf(buf, "active\n");
 118         default:
 119                 return sprintf(buf, "unknown\n");
 120         }
 121 }
 122
 123 static ssize_t
 124 trip_point_temp_store(struct device *dev, struct device_attribute *attr,
 125                       const char *buf, size_t count)
 126 {
 127         struct thermal_zone_device *tz = to_thermal_zone(dev);
 128         int trip, ret;
 129         int temperature;
 130
 131         if (!tz->ops->set_trip_temp)
 132                 return -EPERM;
 133
 134         if (sscanf(attr->attr.name, "trip_point_%d_temp", &trip) != 1)
 135                 return -EINVAL;
 136
 137         if (kstrtoint(buf, 10, &temperature))
 138                 return -EINVAL;
 139
 140         ret = tz->ops->set_trip_temp(tz, trip, temperature);
 141         if (ret)
 142                 return ret;
 143
 144         thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
 145
 146         return count;
 147 }
 148
 149 static ssize_t
 150 trip_point_temp_show(struct device *dev, struct device_attribute *attr,
 151                      char *buf)
 152 {
 153         struct thermal_zone_device *tz = to_thermal_zone(dev);
 154         int trip, ret;
 155         int temperature;
 156
 157         if (!tz->ops->get_trip_temp)
 158                 return -EPERM;
 159
 160         if (sscanf(attr->attr.name, "trip_point_%d_temp", &trip) != 1)
 161                 return -EINVAL;
 162
 163         ret = tz->ops->get_trip_temp(tz, trip, &temperature);
 164
 165         if (ret)
 166                 return ret;
 167
 168         return sprintf(buf, "%d\n", temperature);
 169 }
 170
 171 static ssize_t
 172 trip_point_hyst_store(struct device *dev, struct device_attribute *attr,
 173                       const char *buf, size_t count)
 174 {
 175         struct thermal_zone_device *tz = to_thermal_zone(dev);
 176         int trip, ret;
 177         int temperature;
 178
 179         if (!tz->ops->set_trip_hyst)
 180                 return -EPERM;
 181
 182         if (sscanf(attr->attr.name, "trip_point_%d_hyst", &trip) != 1)
 183                 return -EINVAL;
 184
 185         if (kstrtoint(buf, 10, &temperature))
 186                 return -EINVAL;
 187
 188         /*
 189          * We are not doing any check on the 'temperature' value
 190          * here. The driver implementing 'set_trip_hyst' has to
 191          * take care of this.
 192          */
 193         ret = tz->ops->set_trip_hyst(tz, trip, temperature);
 194
 195         if (!ret)
 196                 thermal_zone_set_trips(tz);
 197
 198         return ret ? ret : count;
 199 }
 200
 201 static ssize_t
 202 trip_point_hyst_show(struct device *dev, struct device_attribute *attr,
 203                      char *buf)
 204 {
 205         struct thermal_zone_device *tz = to_thermal_zone(dev);
 206         int trip, ret;
 207         int temperature;
 208
 209         if (!tz->ops->get_trip_hyst)
 210                 return -EPERM;
 211
 212         if (sscanf(attr->attr.name, "trip_point_%d_hyst", &trip) != 1)
 213                 return -EINVAL;
 214
 215         ret = tz->ops->get_trip_hyst(tz, trip, &temperature);
 216
 217         return ret ? ret : sprintf(buf, "%d\n", temperature);
 218 }
 219
 220 static ssize_t
 221 passive_store(struct device *dev, struct device_attribute *attr,
 222               const char *buf, size_t count)
 223 {
 224         struct thermal_zone_device *tz = to_thermal_zone(dev);
 225         int state;
 226
 227         if (sscanf(buf, "%d\n", &state) != 1)
 228                 return -EINVAL;
 229
 230         /* sanity check: values below 1000 millicelcius don't make sense
 231          * and can cause the system to go into a thermal heart attack
 232          */
 233         if (state && state < 1000)
 234                 return -EINVAL;
 235
 236         if (state && !tz->forced_passive) {
 237                 if (!tz->passive_delay)
 238                         tz->passive_delay = 1000;
 239                 thermal_zone_device_rebind_exception(tz, "Processor",
 240                                                      sizeof("Processor"));
 241         } else if (!state && tz->forced_passive) {
 242                 tz->passive_delay = 0;
 243                 thermal_zone_device_unbind_exception(tz, "Processor",
 244                                                      sizeof("Processor"));
 245         }
 246
 247         tz->forced_passive = state;
 248
 249         thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
 250
 251         return count;
 252 }
 253
 254 static ssize_t
 255 passive_show(struct device *dev, struct device_attribute *attr,
 256              char *buf)
 257 {
 258         struct thermal_zone_device *tz = to_thermal_zone(dev);
 259
 260         return sprintf(buf, "%d\n", tz->forced_passive);
 261 }
 262
 263 static ssize_t
 264 policy_store(struct device *dev, struct device_attribute *attr,
 265              const char *buf, size_t count)
 266 {
 267         struct thermal_zone_device *tz = to_thermal_zone(dev);
 268         char name[THERMAL_NAME_LENGTH];
 269         int ret;
 270
 271         snprintf(name, sizeof(name), "%s", buf);
 272
 273         ret = thermal_zone_device_set_policy(tz, name);
 274         if (!ret)
 275                 ret = count;
 276
 277         return ret;
 278 }
 279
 280 static ssize_t
 281 policy_show(struct device *dev, struct device_attribute *devattr, char *buf)
 282 {
 283         struct thermal_zone_device *tz = to_thermal_zone(dev);
 284
 285         return sprintf(buf, "%s\n", tz->governor->name);
 286 }
 287
 288 static ssize_t
 289 available_policies_show(struct device *dev, struct device_attribute *devattr,
 290                         char *buf)
 291 {
 292         return thermal_build_list_of_policies(buf);
 293 }
 294
 295 static ssize_t
 296 emul_temp_store(struct device *dev, struct device_attribute *attr,
 297                 const char *buf, size_t count)
 298 {
 299         struct thermal_zone_device *tz = to_thermal_zone(dev);
 300         int ret = 0;
 301         int temperature;
 302
 303         if (kstrtoint(buf, 10, &temperature))
 304                 return -EINVAL;
 305
 306         if (!tz->ops->set_emul_temp) {
 307                 mutex_lock(&tz->lock);
 308                 tz->emul_temperature = temperature;
 309                 mutex_unlock(&tz->lock);
 310         } else {
 311                 ret = tz->ops->set_emul_temp(tz, temperature);
 312         }
 313
 314         if (!ret)
 315                 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
 316
 317         return ret ? ret : count;
 318 }
 319
 320 static ssize_t
 321 sustainable_power_show(struct device *dev, struct device_attribute *devattr,
 322                        char *buf)
 323 {
 324         struct thermal_zone_device *tz = to_thermal_zone(dev);
 325
 326         if (tz->tzp)
 327                 return sprintf(buf, "%u\n", tz->tzp->sustainable_power);
 328         else
 329                 return -EIO;
 330 }
 331
 332 static ssize_t
 333 sustainable_power_store(struct device *dev, struct device_attribute *devattr,
 334                         const char *buf, size_t count)
 335 {
 336         struct thermal_zone_device *tz = to_thermal_zone(dev);
 337         u32 sustainable_power;
 338
 339         if (!tz->tzp)
 340                 return -EIO;
 341
 342         if (kstrtou32(buf, 10, &sustainable_power))
 343                 return -EINVAL;
 344
 345         tz->tzp->sustainable_power = sustainable_power;
 346
 347         return count;
 348 }
 349
 350 #define create_s32_tzp_attr(name)                                       \
 351         static ssize_t                                                  \
 352         name##_show(struct device *dev, struct device_attribute *devattr, \
 353                 char *buf)                                              \
 354         {                                                               \
 355         struct thermal_zone_device *tz = to_thermal_zone(dev);          \
 356                                                                         \
 357         if (tz->tzp)                                                    \
 358                 return sprintf(buf, "%d\n", tz->tzp->name);             \
 359         else                                                            \
 360                 return -EIO;                                            \
 361         }                                                               \
 362                                                                         \
 363         static ssize_t                                                  \
 364         name##_store(struct device *dev, struct device_attribute *devattr, \
 365                 const char *buf, size_t count)                          \
 366         {                                                               \
 367                 struct thermal_zone_device *tz = to_thermal_zone(dev);  \
 368                 s32 value;                                              \
 369                                                                         \
 370                 if (!tz->tzp)                                           \
 371                         return -EIO;                                    \
 372                                                                         \
 373                 if (kstrtos32(buf, 10, &value))                         \
 374                         return -EINVAL;                                 \
 375                                                                         \
 376                 tz->tzp->name = value;                                  \
 377                                                                         \
 378                 return count;                                           \
 379         }                                                               \
 380         static DEVICE_ATTR(name, S_IWUSR | S_IRUGO, name##_show, name##_store)
 381
 382 create_s32_tzp_attr(k_po);
 383 create_s32_tzp_attr(k_pu);
 384 create_s32_tzp_attr(k_i);
 385 create_s32_tzp_attr(k_d);
 386 create_s32_tzp_attr(integral_cutoff);
 387 create_s32_tzp_attr(slope);
 388 create_s32_tzp_attr(offset);
 389 #undef create_s32_tzp_attr
 390
 391 /*
 392  * These are thermal zone device attributes that will always be present.
 393  * All the attributes created for tzp (create_s32_tzp_attr) also are always
 394  * present on the sysfs interface.
 395  */
 396 static DEVICE_ATTR(type, 0444, type_show, NULL);
 397 static DEVICE_ATTR(temp, 0444, temp_show, NULL);
 398 static DEVICE_ATTR(emul_temp, S_IWUSR, NULL, emul_temp_store);
 399 static DEVICE_ATTR(policy, S_IRUGO | S_IWUSR, policy_show, policy_store);
 400 static DEVICE_ATTR(available_policies, S_IRUGO, available_policies_show, NULL);
 401 static DEVICE_ATTR(sustainable_power, S_IWUSR | S_IRUGO, sustainable_power_show,
 402                    sustainable_power_store);
 403
 404 /* These thermal zone device attributes are created based on conditions */
 405 static DEVICE_ATTR(mode, 0644, mode_show, mode_store);
 406 static DEVICE_ATTR(passive, S_IRUGO | S_IWUSR, passive_show, passive_store);
 407
 408 /* These attributes are unconditionally added to a thermal zone */
 409 static struct attribute *thermal_zone_dev_attrs[] = {
 410         &dev_attr_type.attr,
 411         &dev_attr_temp.attr,
 412 #if (IS_ENABLED(CONFIG_THERMAL_EMULATION))
 413         &dev_attr_emul_temp.attr,
 414 #endif
 415         &dev_attr_policy.attr,
 416         &dev_attr_available_policies.attr,
 417         &dev_attr_sustainable_power.attr,
 418         &dev_attr_k_po.attr,
 419         &dev_attr_k_pu.attr,
 420         &dev_attr_k_i.attr,
 421         &dev_attr_k_d.attr,
 422         &dev_attr_integral_cutoff.attr,
 423         &dev_attr_slope.attr,
 424         &dev_attr_offset.attr,
 425         NULL,
 426 };
 427
 428 static struct attribute_group thermal_zone_attribute_group = {
 429         .attrs = thermal_zone_dev_attrs,
 430 };
 431
 432 /* We expose mode only if .get_mode is present */
 433 static struct attribute *thermal_zone_mode_attrs[] = {
 434         &dev_attr_mode.attr,
 435         NULL,
 436 };
 437
 438 static umode_t thermal_zone_mode_is_visible(struct kobject *kobj,
 439                                             struct attribute *attr,
 440                                             int attrno)
 441 {
 442         struct device *dev = container_of(kobj, struct device, kobj);
 443         struct thermal_zone_device *tz;
 444
 445         tz = container_of(dev, struct thermal_zone_device, device);
 446
 447         if (tz->ops->get_mode)
 448                 return attr->mode;
 449
 450         return 0;
 451 }
 452
 453 static struct attribute_group thermal_zone_mode_attribute_group = {
 454         .attrs = thermal_zone_mode_attrs,
 455         .is_visible = thermal_zone_mode_is_visible,
 456 };
 457
 458 /* We expose passive only if passive trips are present */
 459 static struct attribute *thermal_zone_passive_attrs[] = {
 460         &dev_attr_passive.attr,
 461         NULL,
 462 };
 463
 464 static umode_t thermal_zone_passive_is_visible(struct kobject *kobj,
 465                                                struct attribute *attr,
 466                                                int attrno)
 467 {
 468         struct device *dev = container_of(kobj, struct device, kobj);
 469         struct thermal_zone_device *tz;
 470         enum thermal_trip_type trip_type;
 471         int count, passive = 0;
 472
 473         tz = container_of(dev, struct thermal_zone_device, device);
 474
 475         for (count = 0; count < tz->trips && !passive; count++) {
 476                 tz->ops->get_trip_type(tz, count, &trip_type);
 477
 478                 if (trip_type == THERMAL_TRIP_PASSIVE)
 479                         passive = 1;
 480         }
 481
 482         if (!passive)
 483                 return attr->mode;
 484
 485         return 0;
 486 }
 487
 488 static struct attribute_group thermal_zone_passive_attribute_group = {
 489         .attrs = thermal_zone_passive_attrs,
 490         .is_visible = thermal_zone_passive_is_visible,
 491 };
 492
 493 static const struct attribute_group *thermal_zone_attribute_groups[] = {
 494         &thermal_zone_attribute_group,
 495         &thermal_zone_mode_attribute_group,
 496         &thermal_zone_passive_attribute_group,
 497         /* This is not NULL terminated as we create the group dynamically */
 498 };
 499
 500 /**
 501  * create_trip_attrs() - create attributes for trip points
 502  * @tz:         the thermal zone device
 503  * @mask:       Writeable trip point bitmap.
 504  *
 505  * helper function to instantiate sysfs entries for every trip
 506  * point and its properties of a struct thermal_zone_device.
 507  *
 508  * Return: 0 on success, the proper error value otherwise.
 509  */
 510 static int create_trip_attrs(struct thermal_zone_device *tz, int mask)
 511 {
 512         int size = sizeof(struct thermal_attr) * tz->trips;
 513         struct attribute **attrs;
 514         int indx;
 515
 516         /* This function works only for zones with at least one trip */
 517         if (tz->trips <= 0)
 518                 return -EINVAL;
 519
 520         tz->trip_type_attrs = kzalloc(size, GFP_KERNEL);
 521         if (!tz->trip_type_attrs)
 522                 return -ENOMEM;
 523
 524         tz->trip_temp_attrs = kzalloc(size, GFP_KERNEL);
 525         if (!tz->trip_temp_attrs) {
 526                 kfree(tz->trip_type_attrs);
 527                 return -ENOMEM;
 528         }
 529
 530         if (tz->ops->get_trip_hyst) {
 531                 tz->trip_hyst_attrs = kzalloc(size, GFP_KERNEL);
 532                 if (!tz->trip_hyst_attrs) {
 533                         kfree(tz->trip_type_attrs);
 534                         kfree(tz->trip_temp_attrs);
 535                         return -ENOMEM;
 536                 }
 537         }
 538
 539         attrs = kzalloc(sizeof(*attrs) * tz->trips * 3 + 1, GFP_KERNEL);
 540         if (!attrs) {
 541                 kfree(tz->trip_type_attrs);
 542                 kfree(tz->trip_temp_attrs);
 543                 if (tz->ops->get_trip_hyst)
 544                         kfree(tz->trip_hyst_attrs);
 545                 return -ENOMEM;
 546         }
 547
 548         for (indx = 0; indx < tz->trips; indx++) {
 549                 /* create trip type attribute */
 550                 snprintf(tz->trip_type_attrs[indx].name, THERMAL_NAME_LENGTH,
 551                          "trip_point_%d_type", indx);
 552
 553                 sysfs_attr_init(&tz->trip_type_attrs[indx].attr.attr);
 554                 tz->trip_type_attrs[indx].attr.attr.name =
 555                                                 tz->trip_type_attrs[indx].name;
 556                 tz->trip_type_attrs[indx].attr.attr.mode = S_IRUGO;
 557                 tz->trip_type_attrs[indx].attr.show = trip_point_type_show;
 558                 attrs[indx] = &tz->trip_type_attrs[indx].attr.attr;
 559
 560                 /* create trip temp attribute */
 561                 snprintf(tz->trip_temp_attrs[indx].name, THERMAL_NAME_LENGTH,
 562                          "trip_point_%d_temp", indx);
 563
 564                 sysfs_attr_init(&tz->trip_temp_attrs[indx].attr.attr);
 565                 tz->trip_temp_attrs[indx].attr.attr.name =
 566                                                 tz->trip_temp_attrs[indx].name;
 567                 tz->trip_temp_attrs[indx].attr.attr.mode = S_IRUGO;
 568                 tz->trip_temp_attrs[indx].attr.show = trip_point_temp_show;
 569                 if (IS_ENABLED(CONFIG_THERMAL_WRITABLE_TRIPS) &&
 570                     mask & (1 << indx)) {
 571                         tz->trip_temp_attrs[indx].attr.attr.mode |= S_IWUSR;
 572                         tz->trip_temp_attrs[indx].attr.store =
 573                                                         trip_point_temp_store;
 574                 }
 575                 attrs[indx + tz->trips] = &tz->trip_temp_attrs[indx].attr.attr;
 576
 577                 /* create Optional trip hyst attribute */
 578                 if (!tz->ops->get_trip_hyst)
 579                         continue;
 580                 snprintf(tz->trip_hyst_attrs[indx].name, THERMAL_NAME_LENGTH,
 581                          "trip_point_%d_hyst", indx);
 582
 583                 sysfs_attr_init(&tz->trip_hyst_attrs[indx].attr.attr);
 584                 tz->trip_hyst_attrs[indx].attr.attr.name =
 585                                         tz->trip_hyst_attrs[indx].name;
 586                 tz->trip_hyst_attrs[indx].attr.attr.mode = S_IRUGO;
 587                 tz->trip_hyst_attrs[indx].attr.show = trip_point_hyst_show;
 588                 if (tz->ops->set_trip_hyst) {
 589                         tz->trip_hyst_attrs[indx].attr.attr.mode |= S_IWUSR;
 590                         tz->trip_hyst_attrs[indx].attr.store =
 591                                         trip_point_hyst_store;
 592                 }
 593                 attrs[indx + tz->trips * 2] =
 594                                         &tz->trip_hyst_attrs[indx].attr.attr;
 595         }
 596         attrs[tz->trips * 3] = NULL;
 597
 598         tz->trips_attribute_group.attrs = attrs;
 599
 600         return 0;
 601 }
 602
 603 int thermal_zone_create_device_groups(struct thermal_zone_device *tz,
 604                                       int mask)
 605 {
 606         const struct attribute_group **groups;
 607         int i, size, result;
 608
 609         /* we need one extra for trips and the NULL to terminate the array */
 610         size = ARRAY_SIZE(thermal_zone_attribute_groups) + 2;
 611         /* This also takes care of API requirement to be NULL terminated */
 612         groups = kcalloc(size, sizeof(*groups), GFP_KERNEL);
 613         if (!groups)
 614                 return -ENOMEM;
 615
 616         for (i = 0; i < size - 2; i++)
 617                 groups[i] = thermal_zone_attribute_groups[i];
 618
 619         if (tz->trips) {
 620                 result = create_trip_attrs(tz, mask);
 621                 if (result) {
 622                         kfree(groups);
 623
 624                         return result;
 625                 }
 626
 627                 groups[size - 2] = &tz->trips_attribute_group;
 628         }
 629
 630         tz->device.groups = groups;
 631
 632         return 0;
 633 }