drivers/base/power/sysfs.c

   1 /*
   2  * drivers/base/power/sysfs.c - sysfs entries for device PM
   3  */
   4
   5 #include <linux/device.h>
   6 #include <linux/string.h>
   7 #include <linux/export.h>
   8 #include <linux/pm_qos.h>
   9 #include <linux/pm_runtime.h>
  10 #include <linux/atomic.h>
  11 #include <linux/jiffies.h>
  12 #include "power.h"
  13
  14 /*
  15  *      control - Report/change current runtime PM setting of the device
  16  *
  17  *      Runtime power management of a device can be blocked with the help of
  18  *      this attribute.  All devices have one of the following two values for
  19  *      the power/control file:
  20  *
  21  *       + "auto\n" to allow the device to be power managed at run time;
  22  *       + "on\n" to prevent the device from being power managed at run time;
  23  *
  24  *      The default for all devices is "auto", which means that devices may be
  25  *      subject to automatic power management, depending on their drivers.
  26  *      Changing this attribute to "on" prevents the driver from power managing
  27  *      the device at run time.  Doing that while the device is suspended causes
  28  *      it to be woken up.
  29  *
  30  *      wakeup - Report/change current wakeup option for device
  31  *
  32  *      Some devices support "wakeup" events, which are hardware signals
  33  *      used to activate devices from suspended or low power states.  Such
  34  *      devices have one of three values for the sysfs power/wakeup file:
  35  *
  36  *       + "enabled\n" to issue the events;
  37  *       + "disabled\n" not to do so; or
  38  *       + "\n" for temporary or permanent inability to issue wakeup.
  39  *
  40  *      (For example, unconfigured USB devices can't issue wakeups.)
  41  *
  42  *      Familiar examples of devices that can issue wakeup events include
  43  *      keyboards and mice (both PS2 and USB styles), power buttons, modems,
  44  *      "Wake-On-LAN" Ethernet links, GPIO lines, and more.  Some events
  45  *      will wake the entire system from a suspend state; others may just
  46  *      wake up the device (if the system as a whole is already active).
  47  *      Some wakeup events use normal IRQ lines; other use special out
  48  *      of band signaling.
  49  *
  50  *      It is the responsibility of device drivers to enable (or disable)
  51  *      wakeup signaling as part of changing device power states, respecting
  52  *      the policy choices provided through the driver model.
  53  *
  54  *      Devices may not be able to generate wakeup events from all power
  55  *      states.  Also, the events may be ignored in some configurations;
  56  *      for example, they might need help from other devices that aren't
  57  *      active, or which may have wakeup disabled.  Some drivers rely on
  58  *      wakeup events internally (unless they are disabled), keeping
  59  *      their hardware in low power modes whenever they're unused.  This
  60  *      saves runtime power, without requiring system-wide sleep states.
  61  *
  62  *      async - Report/change current async suspend setting for the device
  63  *
  64  *      Asynchronous suspend and resume of the device during system-wide power
  65  *      state transitions can be enabled by writing "enabled" to this file.
  66  *      Analogously, if "disabled" is written to this file, the device will be
  67  *      suspended and resumed synchronously.
  68  *
  69  *      All devices have one of the following two values for power/async:
  70  *
  71  *       + "enabled\n" to permit the asynchronous suspend/resume of the device;
  72  *       + "disabled\n" to forbid it;
  73  *
  74  *      NOTE: It generally is unsafe to permit the asynchronous suspend/resume
  75  *      of a device unless it is certain that all of the PM dependencies of the
  76  *      device are known to the PM core.  However, for some devices this
  77  *      attribute is set to "enabled" by bus type code or device drivers and in
  78  *      that cases it should be safe to leave the default value.
  79  *
  80  *      autosuspend_delay_ms - Report/change a device's autosuspend_delay value
  81  *
  82  *      Some drivers don't want to carry out a runtime suspend as soon as a
  83  *      device becomes idle; they want it always to remain idle for some period
  84  *      of time before suspending it.  This period is the autosuspend_delay
  85  *      value (expressed in milliseconds) and it can be controlled by the user.
  86  *      If the value is negative then the device will never be runtime
  87  *      suspended.
  88  *
  89  *      NOTE: The autosuspend_delay_ms attribute and the autosuspend_delay
  90  *      value are used only if the driver calls pm_runtime_use_autosuspend().
  91  *
  92  *      wakeup_count - Report the number of wakeup events related to the device
  93  */
  94
  95 const char power_group_name[] = "power";
  96 EXPORT_SYMBOL_GPL(power_group_name);
  97
  98 static const char ctrl_auto[] = "auto";
  99 static const char ctrl_on[] = "on";
 100
 101 static ssize_t control_show(struct device *dev, struct device_attribute *attr,
 102                             char *buf)
 103 {
 104         return sprintf(buf, "%s\n",
 105                                 dev->power.runtime_auto ? ctrl_auto : ctrl_on);
 106 }
 107
 108 static ssize_t control_store(struct device * dev, struct device_attribute *attr,
 109                              const char * buf, size_t n)
 110 {
 111         device_lock(dev);
 112         if (sysfs_streq(buf, ctrl_auto))
 113                 pm_runtime_allow(dev);
 114         else if (sysfs_streq(buf, ctrl_on))
 115                 pm_runtime_forbid(dev);
 116         else
 117                 n = -EINVAL;
 118         device_unlock(dev);
 119         return n;
 120 }
 121
 122 static DEVICE_ATTR_RW(control);
 123
 124 static ssize_t runtime_active_time_show(struct device *dev,
 125                                 struct device_attribute *attr, char *buf)
 126 {
 127         int ret;
 128         u64 tmp = pm_runtime_active_time(dev);
 129         do_div(tmp, NSEC_PER_MSEC);
 130         ret = sprintf(buf, "%llu\n", tmp);
 131         return ret;
 132 }
 133
 134 static DEVICE_ATTR_RO(runtime_active_time);
 135
 136 static ssize_t runtime_suspended_time_show(struct device *dev,
 137                                 struct device_attribute *attr, char *buf)
 138 {
 139         int ret;
 140         u64 tmp = pm_runtime_suspended_time(dev);
 141         do_div(tmp, NSEC_PER_MSEC);
 142         ret = sprintf(buf, "%llu\n", tmp);
 143         return ret;
 144 }
 145
 146 static DEVICE_ATTR_RO(runtime_suspended_time);
 147
 148 static ssize_t runtime_status_show(struct device *dev,
 149                                 struct device_attribute *attr, char *buf)
 150 {
 151         const char *p;
 152
 153         if (dev->power.runtime_error) {
 154                 p = "error\n";
 155         } else if (dev->power.disable_depth) {
 156                 p = "unsupported\n";
 157         } else {
 158                 switch (dev->power.runtime_status) {
 159                 case RPM_SUSPENDED:
 160                         p = "suspended\n";
 161                         break;
 162                 case RPM_SUSPENDING:
 163                         p = "suspending\n";
 164                         break;
 165                 case RPM_RESUMING:
 166                         p = "resuming\n";
 167                         break;
 168                 case RPM_ACTIVE:
 169                         p = "active\n";
 170                         break;
 171                 default:
 172                         return -EIO;
 173                 }
 174         }
 175         return sprintf(buf, p);
 176 }
 177
 178 static DEVICE_ATTR_RO(runtime_status);
 179
 180 static ssize_t autosuspend_delay_ms_show(struct device *dev,
 181                 struct device_attribute *attr, char *buf)
 182 {
 183         if (!dev->power.use_autosuspend)
 184                 return -EIO;
 185         return sprintf(buf, "%d\n", dev->power.autosuspend_delay);
 186 }
 187
 188 static ssize_t autosuspend_delay_ms_store(struct device *dev,
 189                 struct device_attribute *attr, const char *buf, size_t n)
 190 {
 191         long delay;
 192
 193         if (!dev->power.use_autosuspend)
 194                 return -EIO;
 195
 196         if (kstrtol(buf, 10, &delay) != 0 || delay != (int) delay)
 197                 return -EINVAL;
 198
 199         device_lock(dev);
 200         pm_runtime_set_autosuspend_delay(dev, delay);
 201         device_unlock(dev);
 202         return n;
 203 }
 204
 205 static DEVICE_ATTR_RW(autosuspend_delay_ms);
 206
 207 static ssize_t pm_qos_resume_latency_us_show(struct device *dev,
 208                                              struct device_attribute *attr,
 209                                              char *buf)
 210 {
 211         s32 value = dev_pm_qos_requested_resume_latency(dev);
 212
 213         if (value == 0)
 214                 return sprintf(buf, "n/a\n");
 215         if (value == PM_QOS_RESUME_LATENCY_NO_CONSTRAINT)
 216                 value = 0;
 217
 218         return sprintf(buf, "%d\n", value);
 219 }
 220
 221 static ssize_t pm_qos_resume_latency_us_store(struct device *dev,
 222                                               struct device_attribute *attr,
 223                                               const char *buf, size_t n)
 224 {
 225         s32 value;
 226         int ret;
 227
 228         if (!kstrtos32(buf, 0, &value)) {
 229                 /*
 230                  * Prevent users from writing negative or "no constraint" values
 231                  * directly.
 232                  */
 233                 if (value < 0 || value == PM_QOS_RESUME_LATENCY_NO_CONSTRAINT)
 234                         return -EINVAL;
 235
 236                 if (value == 0)
 237                         value = PM_QOS_RESUME_LATENCY_NO_CONSTRAINT;
 238         } else if (sysfs_streq(buf, "n/a")) {
 239                 value = 0;
 240         } else {
 241                 return -EINVAL;
 242         }
 243
 244         ret = dev_pm_qos_update_request(dev->power.qos->resume_latency_req,
 245                                         value);
 246         return ret < 0 ? ret : n;
 247 }
 248
 249 static DEVICE_ATTR_RW(pm_qos_resume_latency_us);
 250
 251 static ssize_t pm_qos_latency_tolerance_us_show(struct device *dev,
 252                                                 struct device_attribute *attr,
 253                                                 char *buf)
 254 {
 255         s32 value = dev_pm_qos_get_user_latency_tolerance(dev);
 256
 257         if (value < 0)
 258                 return sprintf(buf, "auto\n");
 259         if (value == PM_QOS_LATENCY_ANY)
 260                 return sprintf(buf, "any\n");
 261
 262         return sprintf(buf, "%d\n", value);
 263 }
 264
 265 static ssize_t pm_qos_latency_tolerance_us_store(struct device *dev,
 266                                                  struct device_attribute *attr,
 267                                                  const char *buf, size_t n)
 268 {
 269         s32 value;
 270         int ret;
 271
 272         if (kstrtos32(buf, 0, &value) == 0) {
 273                 /* Users can't write negative values directly */
 274                 if (value < 0)
 275                         return -EINVAL;
 276         } else {
 277                 if (sysfs_streq(buf, "auto"))
 278                         value = PM_QOS_LATENCY_TOLERANCE_NO_CONSTRAINT;
 279                 else if (sysfs_streq(buf, "any"))
 280                         value = PM_QOS_LATENCY_ANY;
 281                 else
 282                         return -EINVAL;
 283         }
 284         ret = dev_pm_qos_update_user_latency_tolerance(dev, value);
 285         return ret < 0 ? ret : n;
 286 }
 287
 288 static DEVICE_ATTR_RW(pm_qos_latency_tolerance_us);
 289
 290 static ssize_t pm_qos_no_power_off_show(struct device *dev,
 291                                         struct device_attribute *attr,
 292                                         char *buf)
 293 {
 294         return sprintf(buf, "%d\n", !!(dev_pm_qos_requested_flags(dev)
 295                                         & PM_QOS_FLAG_NO_POWER_OFF));
 296 }
 297
 298 static ssize_t pm_qos_no_power_off_store(struct device *dev,
 299                                          struct device_attribute *attr,
 300                                          const char *buf, size_t n)
 301 {
 302         int ret;
 303
 304         if (kstrtoint(buf, 0, &ret))
 305                 return -EINVAL;
 306
 307         if (ret != 0 && ret != 1)
 308                 return -EINVAL;
 309
 310         ret = dev_pm_qos_update_flags(dev, PM_QOS_FLAG_NO_POWER_OFF, ret);
 311         return ret < 0 ? ret : n;
 312 }
 313
 314 static DEVICE_ATTR_RW(pm_qos_no_power_off);
 315
 316 #ifdef CONFIG_PM_SLEEP
 317 static const char _enabled[] = "enabled";
 318 static const char _disabled[] = "disabled";
 319
 320 static ssize_t wakeup_show(struct device *dev, struct device_attribute *attr,
 321                            char *buf)
 322 {
 323         return sprintf(buf, "%s\n", device_can_wakeup(dev)
 324                 ? (device_may_wakeup(dev) ? _enabled : _disabled)
 325                 : "");
 326 }
 327
 328 static ssize_t wakeup_store(struct device *dev, struct device_attribute *attr,
 329                             const char *buf, size_t n)
 330 {
 331         if (!device_can_wakeup(dev))
 332                 return -EINVAL;
 333
 334         if (sysfs_streq(buf, _enabled))
 335                 device_set_wakeup_enable(dev, 1);
 336         else if (sysfs_streq(buf, _disabled))
 337                 device_set_wakeup_enable(dev, 0);
 338         else
 339                 return -EINVAL;
 340         return n;
 341 }
 342
 343 static DEVICE_ATTR_RW(wakeup);
 344
 345 static ssize_t wakeup_count_show(struct device *dev,
 346                                  struct device_attribute *attr, char *buf)
 347 {
 348         unsigned long count = 0;
 349         bool enabled = false;
 350
 351         spin_lock_irq(&dev->power.lock);
 352         if (dev->power.wakeup) {
 353                 count = dev->power.wakeup->wakeup_count;
 354                 enabled = true;
 355         }
 356         spin_unlock_irq(&dev->power.lock);
 357         return enabled ? sprintf(buf, "%lu\n", count) : sprintf(buf, "\n");
 358 }
 359
 360 static DEVICE_ATTR_RO(wakeup_count);
 361
 362 static ssize_t wakeup_active_count_show(struct device *dev,
 363                                         struct device_attribute *attr,
 364                                         char *buf)
 365 {
 366         unsigned long count = 0;
 367         bool enabled = false;
 368
 369         spin_lock_irq(&dev->power.lock);
 370         if (dev->power.wakeup) {
 371                 count = dev->power.wakeup->active_count;
 372                 enabled = true;
 373         }
 374         spin_unlock_irq(&dev->power.lock);
 375         return enabled ? sprintf(buf, "%lu\n", count) : sprintf(buf, "\n");
 376 }
 377
 378 static DEVICE_ATTR_RO(wakeup_active_count);
 379
 380 static ssize_t wakeup_abort_count_show(struct device *dev,
 381                                        struct device_attribute *attr,
 382                                        char *buf)
 383 {
 384         unsigned long count = 0;
 385         bool enabled = false;
 386
 387         spin_lock_irq(&dev->power.lock);
 388         if (dev->power.wakeup) {
 389                 count = dev->power.wakeup->wakeup_count;
 390                 enabled = true;
 391         }
 392         spin_unlock_irq(&dev->power.lock);
 393         return enabled ? sprintf(buf, "%lu\n", count) : sprintf(buf, "\n");
 394 }
 395
 396 static DEVICE_ATTR_RO(wakeup_abort_count);
 397
 398 static ssize_t wakeup_expire_count_show(struct device *dev,
 399                                         struct device_attribute *attr,
 400                                         char *buf)
 401 {
 402         unsigned long count = 0;
 403         bool enabled = false;
 404
 405         spin_lock_irq(&dev->power.lock);
 406         if (dev->power.wakeup) {
 407                 count = dev->power.wakeup->expire_count;
 408                 enabled = true;
 409         }
 410         spin_unlock_irq(&dev->power.lock);
 411         return enabled ? sprintf(buf, "%lu\n", count) : sprintf(buf, "\n");
 412 }
 413
 414 static DEVICE_ATTR_RO(wakeup_expire_count);
 415
 416 static ssize_t wakeup_active_show(struct device *dev,
 417                                   struct device_attribute *attr, char *buf)
 418 {
 419         unsigned int active = 0;
 420         bool enabled = false;
 421
 422         spin_lock_irq(&dev->power.lock);
 423         if (dev->power.wakeup) {
 424                 active = dev->power.wakeup->active;
 425                 enabled = true;
 426         }
 427         spin_unlock_irq(&dev->power.lock);
 428         return enabled ? sprintf(buf, "%u\n", active) : sprintf(buf, "\n");
 429 }
 430
 431 static DEVICE_ATTR_RO(wakeup_active);
 432
 433 static ssize_t wakeup_total_time_ms_show(struct device *dev,
 434                                          struct device_attribute *attr,
 435                                          char *buf)
 436 {
 437         s64 msec = 0;
 438         bool enabled = false;
 439
 440         spin_lock_irq(&dev->power.lock);
 441         if (dev->power.wakeup) {
 442                 msec = ktime_to_ms(dev->power.wakeup->total_time);
 443                 enabled = true;
 444         }
 445         spin_unlock_irq(&dev->power.lock);
 446         return enabled ? sprintf(buf, "%lld\n", msec) : sprintf(buf, "\n");
 447 }
 448
 449 static DEVICE_ATTR_RO(wakeup_total_time_ms);
 450
 451 static ssize_t wakeup_max_time_ms_show(struct device *dev,
 452                                        struct device_attribute *attr, char *buf)
 453 {
 454         s64 msec = 0;
 455         bool enabled = false;
 456
 457         spin_lock_irq(&dev->power.lock);
 458         if (dev->power.wakeup) {
 459                 msec = ktime_to_ms(dev->power.wakeup->max_time);
 460                 enabled = true;
 461         }
 462         spin_unlock_irq(&dev->power.lock);
 463         return enabled ? sprintf(buf, "%lld\n", msec) : sprintf(buf, "\n");
 464 }
 465
 466 static DEVICE_ATTR_RO(wakeup_max_time_ms);
 467
 468 static ssize_t wakeup_last_time_ms_show(struct device *dev,
 469                                         struct device_attribute *attr,
 470                                         char *buf)
 471 {
 472         s64 msec = 0;
 473         bool enabled = false;
 474
 475         spin_lock_irq(&dev->power.lock);
 476         if (dev->power.wakeup) {
 477                 msec = ktime_to_ms(dev->power.wakeup->last_time);
 478                 enabled = true;
 479         }
 480         spin_unlock_irq(&dev->power.lock);
 481         return enabled ? sprintf(buf, "%lld\n", msec) : sprintf(buf, "\n");
 482 }
 483
 484 static DEVICE_ATTR_RO(wakeup_last_time_ms);
 485
 486 #ifdef CONFIG_PM_AUTOSLEEP
 487 static ssize_t wakeup_prevent_sleep_time_ms_show(struct device *dev,
 488                                                  struct device_attribute *attr,
 489                                                  char *buf)
 490 {
 491         s64 msec = 0;
 492         bool enabled = false;
 493
 494         spin_lock_irq(&dev->power.lock);
 495         if (dev->power.wakeup) {
 496                 msec = ktime_to_ms(dev->power.wakeup->prevent_sleep_time);
 497                 enabled = true;
 498         }
 499         spin_unlock_irq(&dev->power.lock);
 500         return enabled ? sprintf(buf, "%lld\n", msec) : sprintf(buf, "\n");
 501 }
 502
 503 static DEVICE_ATTR_RO(wakeup_prevent_sleep_time_ms);
 504 #endif /* CONFIG_PM_AUTOSLEEP */
 505 #endif /* CONFIG_PM_SLEEP */
 506
 507 #ifdef CONFIG_PM_ADVANCED_DEBUG
 508 static ssize_t runtime_usage_show(struct device *dev,
 509                                   struct device_attribute *attr, char *buf)
 510 {
 511         return sprintf(buf, "%d\n", atomic_read(&dev->power.usage_count));
 512 }
 513 static DEVICE_ATTR_RO(runtime_usage);
 514
 515 static ssize_t runtime_active_kids_show(struct device *dev,
 516                                         struct device_attribute *attr,
 517                                         char *buf)
 518 {
 519         return sprintf(buf, "%d\n", dev->power.ignore_children ?
 520                 0 : atomic_read(&dev->power.child_count));
 521 }
 522 static DEVICE_ATTR_RO(runtime_active_kids);
 523
 524 static ssize_t runtime_enabled_show(struct device *dev,
 525                                     struct device_attribute *attr, char *buf)
 526 {
 527         if (dev->power.disable_depth && (dev->power.runtime_auto == false))
 528                 return sprintf(buf, "disabled & forbidden\n");
 529         if (dev->power.disable_depth)
 530                 return sprintf(buf, "disabled\n");
 531         if (dev->power.runtime_auto == false)
 532                 return sprintf(buf, "forbidden\n");
 533         return sprintf(buf, "enabled\n");
 534 }
 535 static DEVICE_ATTR_RO(runtime_enabled);
 536
 537 #ifdef CONFIG_PM_SLEEP
 538 static ssize_t async_show(struct device *dev, struct device_attribute *attr,
 539                           char *buf)
 540 {
 541         return sprintf(buf, "%s\n",
 542                         device_async_suspend_enabled(dev) ?
 543                                 _enabled : _disabled);
 544 }
 545
 546 static ssize_t async_store(struct device *dev, struct device_attribute *attr,
 547                            const char *buf, size_t n)
 548 {
 549         if (sysfs_streq(buf, _enabled))
 550                 device_enable_async_suspend(dev);
 551         else if (sysfs_streq(buf, _disabled))
 552                 device_disable_async_suspend(dev);
 553         else
 554                 return -EINVAL;
 555         return n;
 556 }
 557
 558 static DEVICE_ATTR_RW(async);
 559
 560 #endif /* CONFIG_PM_SLEEP */
 561 #endif /* CONFIG_PM_ADVANCED_DEBUG */
 562
 563 static struct attribute *power_attrs[] = {
 564 #ifdef CONFIG_PM_ADVANCED_DEBUG
 565 #ifdef CONFIG_PM_SLEEP
 566         &dev_attr_async.attr,
 567 #endif
 568         &dev_attr_runtime_status.attr,
 569         &dev_attr_runtime_usage.attr,
 570         &dev_attr_runtime_active_kids.attr,
 571         &dev_attr_runtime_enabled.attr,
 572 #endif /* CONFIG_PM_ADVANCED_DEBUG */
 573         NULL,
 574 };
 575 static const struct attribute_group pm_attr_group = {
 576         .name   = power_group_name,
 577         .attrs  = power_attrs,
 578 };
 579
 580 static struct attribute *wakeup_attrs[] = {
 581 #ifdef CONFIG_PM_SLEEP
 582         &dev_attr_wakeup.attr,
 583         &dev_attr_wakeup_count.attr,
 584         &dev_attr_wakeup_active_count.attr,
 585         &dev_attr_wakeup_abort_count.attr,
 586         &dev_attr_wakeup_expire_count.attr,
 587         &dev_attr_wakeup_active.attr,
 588         &dev_attr_wakeup_total_time_ms.attr,
 589         &dev_attr_wakeup_max_time_ms.attr,
 590         &dev_attr_wakeup_last_time_ms.attr,
 591 #ifdef CONFIG_PM_AUTOSLEEP
 592         &dev_attr_wakeup_prevent_sleep_time_ms.attr,
 593 #endif
 594 #endif
 595         NULL,
 596 };
 597 static const struct attribute_group pm_wakeup_attr_group = {
 598         .name   = power_group_name,
 599         .attrs  = wakeup_attrs,
 600 };
 601
 602 static struct attribute *runtime_attrs[] = {
 603 #ifndef CONFIG_PM_ADVANCED_DEBUG
 604         &dev_attr_runtime_status.attr,
 605 #endif
 606         &dev_attr_control.attr,
 607         &dev_attr_runtime_suspended_time.attr,
 608         &dev_attr_runtime_active_time.attr,
 609         &dev_attr_autosuspend_delay_ms.attr,
 610         NULL,
 611 };
 612 static const struct attribute_group pm_runtime_attr_group = {
 613         .name   = power_group_name,
 614         .attrs  = runtime_attrs,
 615 };
 616
 617 static struct attribute *pm_qos_resume_latency_attrs[] = {
 618         &dev_attr_pm_qos_resume_latency_us.attr,
 619         NULL,
 620 };
 621 static const struct attribute_group pm_qos_resume_latency_attr_group = {
 622         .name   = power_group_name,
 623         .attrs  = pm_qos_resume_latency_attrs,
 624 };
 625
 626 static struct attribute *pm_qos_latency_tolerance_attrs[] = {
 627         &dev_attr_pm_qos_latency_tolerance_us.attr,
 628         NULL,
 629 };
 630 static const struct attribute_group pm_qos_latency_tolerance_attr_group = {
 631         .name   = power_group_name,
 632         .attrs  = pm_qos_latency_tolerance_attrs,
 633 };
 634
 635 static struct attribute *pm_qos_flags_attrs[] = {
 636         &dev_attr_pm_qos_no_power_off.attr,
 637         NULL,
 638 };
 639 static const struct attribute_group pm_qos_flags_attr_group = {
 640         .name   = power_group_name,
 641         .attrs  = pm_qos_flags_attrs,
 642 };
 643
 644 int dpm_sysfs_add(struct device *dev)
 645 {
 646         int rc;
 647
 648         /* No need to create PM sysfs if explicitly disabled. */
 649         if (device_pm_not_required(dev))
 650                 return 0;
 651
 652         rc = sysfs_create_group(&dev->kobj, &pm_attr_group);
 653         if (rc)
 654                 return rc;
 655
 656         if (pm_runtime_callbacks_present(dev)) {
 657                 rc = sysfs_merge_group(&dev->kobj, &pm_runtime_attr_group);
 658                 if (rc)
 659                         goto err_out;
 660         }
 661         if (device_can_wakeup(dev)) {
 662                 rc = sysfs_merge_group(&dev->kobj, &pm_wakeup_attr_group);
 663                 if (rc)
 664                         goto err_runtime;
 665         }
 666         if (dev->power.set_latency_tolerance) {
 667                 rc = sysfs_merge_group(&dev->kobj,
 668                                        &pm_qos_latency_tolerance_attr_group);
 669                 if (rc)
 670                         goto err_wakeup;
 671         }
 672         return 0;
 673
 674  err_wakeup:
 675         sysfs_unmerge_group(&dev->kobj, &pm_wakeup_attr_group);
 676  err_runtime:
 677         sysfs_unmerge_group(&dev->kobj, &pm_runtime_attr_group);
 678  err_out:
 679         sysfs_remove_group(&dev->kobj, &pm_attr_group);
 680         return rc;
 681 }
 682
 683 int wakeup_sysfs_add(struct device *dev)
 684 {
 685         return sysfs_merge_group(&dev->kobj, &pm_wakeup_attr_group);
 686 }
 687
 688 void wakeup_sysfs_remove(struct device *dev)
 689 {
 690         sysfs_unmerge_group(&dev->kobj, &pm_wakeup_attr_group);
 691 }
 692
 693 int pm_qos_sysfs_add_resume_latency(struct device *dev)
 694 {
 695         return sysfs_merge_group(&dev->kobj, &pm_qos_resume_latency_attr_group);
 696 }
 697
 698 void pm_qos_sysfs_remove_resume_latency(struct device *dev)
 699 {
 700         sysfs_unmerge_group(&dev->kobj, &pm_qos_resume_latency_attr_group);
 701 }
 702
 703 int pm_qos_sysfs_add_flags(struct device *dev)
 704 {
 705         return sysfs_merge_group(&dev->kobj, &pm_qos_flags_attr_group);
 706 }
 707
 708 void pm_qos_sysfs_remove_flags(struct device *dev)
 709 {
 710         sysfs_unmerge_group(&dev->kobj, &pm_qos_flags_attr_group);
 711 }
 712
 713 int pm_qos_sysfs_add_latency_tolerance(struct device *dev)
 714 {
 715         return sysfs_merge_group(&dev->kobj,
 716                                  &pm_qos_latency_tolerance_attr_group);
 717 }
 718
 719 void pm_qos_sysfs_remove_latency_tolerance(struct device *dev)
 720 {
 721         sysfs_unmerge_group(&dev->kobj, &pm_qos_latency_tolerance_attr_group);
 722 }
 723
 724 void rpm_sysfs_remove(struct device *dev)
 725 {
 726         sysfs_unmerge_group(&dev->kobj, &pm_runtime_attr_group);
 727 }
 728
 729 void dpm_sysfs_remove(struct device *dev)
 730 {
 731         if (device_pm_not_required(dev))
 732                 return;
 733         sysfs_unmerge_group(&dev->kobj, &pm_qos_latency_tolerance_attr_group);
 734         dev_pm_qos_constraints_destroy(dev);
 735         rpm_sysfs_remove(dev);
 736         sysfs_unmerge_group(&dev->kobj, &pm_wakeup_attr_group);
 737         sysfs_remove_group(&dev->kobj, &pm_attr_group);
 738 }