drivers/base/power/runtime.c

   1 /*
   2  * drivers/base/power/runtime.c - Helper functions for device runtime PM
   3  *
   4  * Copyright (c) 2009 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc.
   5  * Copyright (C) 2010 Alan Stern <stern@rowland.harvard.edu>
   6  *
   7  * This file is released under the GPLv2.
   8  */
   9
  10 #include <linux/sched.h>
  11 #include <linux/export.h>
  12 #include <linux/pm_runtime.h>
  13 #include <trace/events/rpm.h>
  14 #include "power.h"
  15
  16 static int rpm_resume(struct device *dev, int rpmflags);
  17 static int rpm_suspend(struct device *dev, int rpmflags);
  18
  19 /**
  20  * update_pm_runtime_accounting - Update the time accounting of power states
  21  * @dev: Device to update the accounting for
  22  *
  23  * In order to be able to have time accounting of the various power states
  24  * (as used by programs such as PowerTOP to show the effectiveness of runtime
  25  * PM), we need to track the time spent in each state.
  26  * update_pm_runtime_accounting must be called each time before the
  27  * runtime_status field is updated, to account the time in the old state
  28  * correctly.
  29  */
  30 void update_pm_runtime_accounting(struct device *dev)
  31 {
  32         unsigned long now = jiffies;
  33         unsigned long delta;
  34
  35         delta = now - dev->power.accounting_timestamp;
  36
  37         dev->power.accounting_timestamp = now;
  38
  39         if (dev->power.disable_depth > 0)
  40                 return;
  41
  42         if (dev->power.runtime_status == RPM_SUSPENDED)
  43                 dev->power.suspended_jiffies += delta;
  44         else
  45                 dev->power.active_jiffies += delta;
  46 }
  47
  48 static void __update_runtime_status(struct device *dev, enum rpm_status status)
  49 {
  50         update_pm_runtime_accounting(dev);
  51         dev->power.runtime_status = status;
  52 }
  53
  54 /**
  55  * pm_runtime_deactivate_timer - Deactivate given device's suspend timer.
  56  * @dev: Device to handle.
  57  */
  58 static void pm_runtime_deactivate_timer(struct device *dev)
  59 {
  60         if (dev->power.timer_expires > 0) {
  61                 del_timer(&dev->power.suspend_timer);
  62                 dev->power.timer_expires = 0;
  63         }
  64 }
  65
  66 /**
  67  * pm_runtime_cancel_pending - Deactivate suspend timer and cancel requests.
  68  * @dev: Device to handle.
  69  */
  70 static void pm_runtime_cancel_pending(struct device *dev)
  71 {
  72         pm_runtime_deactivate_timer(dev);
  73         /*
  74          * In case there's a request pending, make sure its work function will
  75          * return without doing anything.
  76          */
  77         dev->power.request = RPM_REQ_NONE;
  78 }
  79
  80 /*
  81  * pm_runtime_autosuspend_expiration - Get a device's autosuspend-delay expiration time.
  82  * @dev: Device to handle.
  83  *
  84  * Compute the autosuspend-delay expiration time based on the device's
  85  * power.last_busy time.  If the delay has already expired or is disabled
  86  * (negative) or the power.use_autosuspend flag isn't set, return 0.
  87  * Otherwise return the expiration time in jiffies (adjusted to be nonzero).
  88  *
  89  * This function may be called either with or without dev->power.lock held.
  90  * Either way it can be racy, since power.last_busy may be updated at any time.
  91  */
  92 unsigned long pm_runtime_autosuspend_expiration(struct device *dev)
  93 {
  94         int autosuspend_delay;
  95         long elapsed;
  96         unsigned long last_busy;
  97         unsigned long expires = 0;
  98
  99         if (!dev->power.use_autosuspend)
 100                 goto out;
 101
 102         autosuspend_delay = ACCESS_ONCE(dev->power.autosuspend_delay);
 103         if (autosuspend_delay < 0)
 104                 goto out;
 105
 106         last_busy = ACCESS_ONCE(dev->power.last_busy);
 107         elapsed = jiffies - last_busy;
 108         if (elapsed < 0)
 109                 goto out;       /* jiffies has wrapped around. */
 110
 111         /*
 112          * If the autosuspend_delay is >= 1 second, align the timer by rounding
 113          * up to the nearest second.
 114          */
 115         expires = last_busy + msecs_to_jiffies(autosuspend_delay);
 116         if (autosuspend_delay >= 1000)
 117                 expires = round_jiffies(expires);
 118         expires += !expires;
 119         if (elapsed >= expires - last_busy)
 120                 expires = 0;    /* Already expired. */
 121
 122  out:
 123         return expires;
 124 }
 125 EXPORT_SYMBOL_GPL(pm_runtime_autosuspend_expiration);
 126
 127 /**
 128  * rpm_check_suspend_allowed - Test whether a device may be suspended.
 129  * @dev: Device to test.
 130  */
 131 static int rpm_check_suspend_allowed(struct device *dev)
 132 {
 133         int retval = 0;
 134
 135         if (dev->power.runtime_error)
 136                 retval = -EINVAL;
 137         else if (dev->power.disable_depth > 0)
 138                 retval = -EACCES;
 139         else if (atomic_read(&dev->power.usage_count) > 0)
 140                 retval = -EAGAIN;
 141         else if (!pm_children_suspended(dev))
 142                 retval = -EBUSY;
 143
 144         /* Pending resume requests take precedence over suspends. */
 145         else if ((dev->power.deferred_resume
 146                         && dev->power.runtime_status == RPM_SUSPENDING)
 147             || (dev->power.request_pending
 148                         && dev->power.request == RPM_REQ_RESUME))
 149                 retval = -EAGAIN;
 150         else if (dev->power.runtime_status == RPM_SUSPENDED)
 151                 retval = 1;
 152
 153         return retval;
 154 }
 155
 156 /**
 157  * __rpm_callback - Run a given runtime PM callback for a given device.
 158  * @cb: Runtime PM callback to run.
 159  * @dev: Device to run the callback for.
 160  */
 161 static int __rpm_callback(int (*cb)(struct device *), struct device *dev)
 162         __releases(&dev->power.lock) __acquires(&dev->power.lock)
 163 {
 164         int retval;
 165
 166         if (dev->power.irq_safe)
 167                 spin_unlock(&dev->power.lock);
 168         else
 169                 spin_unlock_irq(&dev->power.lock);
 170
 171         retval = cb(dev);
 172
 173         if (dev->power.irq_safe)
 174                 spin_lock(&dev->power.lock);
 175         else
 176                 spin_lock_irq(&dev->power.lock);
 177
 178         return retval;
 179 }
 180
 181 /**
 182  * rpm_idle - Notify device bus type if the device can be suspended.
 183  * @dev: Device to notify the bus type about.
 184  * @rpmflags: Flag bits.
 185  *
 186  * Check if the device's runtime PM status allows it to be suspended.  If
 187  * another idle notification has been started earlier, return immediately.  If
 188  * the RPM_ASYNC flag is set then queue an idle-notification request; otherwise
 189  * run the ->runtime_idle() callback directly.
 190  *
 191  * This function must be called under dev->power.lock with interrupts disabled.
 192  */
 193 static int rpm_idle(struct device *dev, int rpmflags)
 194 {
 195         int (*callback)(struct device *);
 196         int retval;
 197
 198         trace_rpm_idle(dev, rpmflags);
 199         retval = rpm_check_suspend_allowed(dev);
 200         if (retval < 0)
 201                 ;       /* Conditions are wrong. */
 202
 203         /* Idle notifications are allowed only in the RPM_ACTIVE state. */
 204         else if (dev->power.runtime_status != RPM_ACTIVE)
 205                 retval = -EAGAIN;
 206
 207         /*
 208          * Any pending request other than an idle notification takes
 209          * precedence over us, except that the timer may be running.
 210          */
 211         else if (dev->power.request_pending &&
 212             dev->power.request > RPM_REQ_IDLE)
 213                 retval = -EAGAIN;
 214
 215         /* Act as though RPM_NOWAIT is always set. */
 216         else if (dev->power.idle_notification)
 217                 retval = -EINPROGRESS;
 218         if (retval)
 219                 goto out;
 220
 221         /* Pending requests need to be canceled. */
 222         dev->power.request = RPM_REQ_NONE;
 223
 224         if (dev->power.no_callbacks) {
 225                 /* Assume ->runtime_idle() callback would have suspended. */
 226                 retval = rpm_suspend(dev, rpmflags);
 227                 goto out;
 228         }
 229
 230         /* Carry out an asynchronous or a synchronous idle notification. */
 231         if (rpmflags & RPM_ASYNC) {
 232                 dev->power.request = RPM_REQ_IDLE;
 233                 if (!dev->power.request_pending) {
 234                         dev->power.request_pending = true;
 235                         queue_work(pm_wq, &dev->power.work);
 236                 }
 237                 goto out;
 238         }
 239
 240         dev->power.idle_notification = true;
 241
 242         if (dev->pm_domain)
 243                 callback = dev->pm_domain->ops.runtime_idle;
 244         else if (dev->type && dev->type->pm)
 245                 callback = dev->type->pm->runtime_idle;
 246         else if (dev->class && dev->class->pm)
 247                 callback = dev->class->pm->runtime_idle;
 248         else if (dev->bus && dev->bus->pm)
 249                 callback = dev->bus->pm->runtime_idle;
 250         else
 251                 callback = NULL;
 252
 253         if (!callback && dev->driver && dev->driver->pm)
 254                 callback = dev->driver->pm->runtime_idle;
 255
 256         if (callback)
 257                 __rpm_callback(callback, dev);
 258
 259         dev->power.idle_notification = false;
 260         wake_up_all(&dev->power.wait_queue);
 261
 262  out:
 263         trace_rpm_return_int(dev, _THIS_IP_, retval);
 264         return retval;
 265 }
 266
 267 /**
 268  * rpm_callback - Run a given runtime PM callback for a given device.
 269  * @cb: Runtime PM callback to run.
 270  * @dev: Device to run the callback for.
 271  */
 272 static int rpm_callback(int (*cb)(struct device *), struct device *dev)
 273 {
 274         int retval;
 275
 276         if (!cb)
 277                 return -ENOSYS;
 278
 279         retval = __rpm_callback(cb, dev);
 280
 281         dev->power.runtime_error = retval;
 282         return retval != -EACCES ? retval : -EIO;
 283 }
 284
 285 /**
 286  * rpm_suspend - Carry out runtime suspend of given device.
 287  * @dev: Device to suspend.
 288  * @rpmflags: Flag bits.
 289  *
 290  * Check if the device's runtime PM status allows it to be suspended.
 291  * Cancel a pending idle notification, autosuspend or suspend. If
 292  * another suspend has been started earlier, either return immediately
 293  * or wait for it to finish, depending on the RPM_NOWAIT and RPM_ASYNC
 294  * flags. If the RPM_ASYNC flag is set then queue a suspend request;
 295  * otherwise run the ->runtime_suspend() callback directly. When
 296  * ->runtime_suspend succeeded, if a deferred resume was requested while
 297  * the callback was running then carry it out, otherwise send an idle
 298  * notification for its parent (if the suspend succeeded and both
 299  * ignore_children of parent->power and irq_safe of dev->power are not set).
 300  * If ->runtime_suspend failed with -EAGAIN or -EBUSY, and if the RPM_AUTO
 301  * flag is set and the next autosuspend-delay expiration time is in the
 302  * future, schedule another autosuspend attempt.
 303  *
 304  * This function must be called under dev->power.lock with interrupts disabled.
 305  */
 306 static int rpm_suspend(struct device *dev, int rpmflags)
 307         __releases(&dev->power.lock) __acquires(&dev->power.lock)
 308 {
 309         int (*callback)(struct device *);
 310         struct device *parent = NULL;
 311         int retval;
 312
 313         trace_rpm_suspend(dev, rpmflags);
 314
 315  repeat:
 316         retval = rpm_check_suspend_allowed(dev);
 317
 318         if (retval < 0)
 319                 ;       /* Conditions are wrong. */
 320
 321         /* Synchronous suspends are not allowed in the RPM_RESUMING state. */
 322         else if (dev->power.runtime_status == RPM_RESUMING &&
 323             !(rpmflags & RPM_ASYNC))
 324                 retval = -EAGAIN;
 325         if (retval)
 326                 goto out;
 327
 328         /* If the autosuspend_delay time hasn't expired yet, reschedule. */
 329         if ((rpmflags & RPM_AUTO)
 330             && dev->power.runtime_status != RPM_SUSPENDING) {
 331                 unsigned long expires = pm_runtime_autosuspend_expiration(dev);
 332
 333                 if (expires != 0) {
 334                         /* Pending requests need to be canceled. */
 335                         dev->power.request = RPM_REQ_NONE;
 336
 337                         /*
 338                          * Optimization: If the timer is already running and is
 339                          * set to expire at or before the autosuspend delay,
 340                          * avoid the overhead of resetting it.  Just let it
 341                          * expire; pm_suspend_timer_fn() will take care of the
 342                          * rest.
 343                          */
 344                         if (!(dev->power.timer_expires && time_before_eq(
 345                             dev->power.timer_expires, expires))) {
 346                                 dev->power.timer_expires = expires;
 347                                 mod_timer(&dev->power.suspend_timer, expires);
 348                         }
 349                         dev->power.timer_autosuspends = 1;
 350                         goto out;
 351                 }
 352         }
 353
 354         /* Other scheduled or pending requests need to be canceled. */
 355         pm_runtime_cancel_pending(dev);
 356
 357         if (dev->power.runtime_status == RPM_SUSPENDING) {
 358                 DEFINE_WAIT(wait);
 359
 360                 if (rpmflags & (RPM_ASYNC | RPM_NOWAIT)) {
 361                         retval = -EINPROGRESS;
 362                         goto out;
 363                 }
 364
 365                 if (dev->power.irq_safe) {
 366                         spin_unlock(&dev->power.lock);
 367
 368                         cpu_relax();
 369
 370                         spin_lock(&dev->power.lock);
 371                         goto repeat;
 372                 }
 373
 374                 /* Wait for the other suspend running in parallel with us. */
 375                 for (;;) {
 376                         prepare_to_wait(&dev->power.wait_queue, &wait,
 377                                         TASK_UNINTERRUPTIBLE);
 378                         if (dev->power.runtime_status != RPM_SUSPENDING)
 379                                 break;
 380
 381                         spin_unlock_irq(&dev->power.lock);
 382
 383                         schedule();
 384
 385                         spin_lock_irq(&dev->power.lock);
 386                 }
 387                 finish_wait(&dev->power.wait_queue, &wait);
 388                 goto repeat;
 389         }
 390
 391         dev->power.deferred_resume = false;
 392         if (dev->power.no_callbacks)
 393                 goto no_callback;       /* Assume success. */
 394
 395         /* Carry out an asynchronous or a synchronous suspend. */
 396         if (rpmflags & RPM_ASYNC) {
 397                 dev->power.request = (rpmflags & RPM_AUTO) ?
 398                     RPM_REQ_AUTOSUSPEND : RPM_REQ_SUSPEND;
 399                 if (!dev->power.request_pending) {
 400                         dev->power.request_pending = true;
 401                         queue_work(pm_wq, &dev->power.work);
 402                 }
 403                 goto out;
 404         }
 405
 406         if (__dev_pm_qos_read_value(dev) < 0) {
 407                 /* Negative PM QoS constraint means "never suspend". */
 408                 retval = -EPERM;
 409                 goto out;
 410         }
 411
 412         __update_runtime_status(dev, RPM_SUSPENDING);
 413
 414         if (dev->pm_domain)
 415                 callback = dev->pm_domain->ops.runtime_suspend;
 416         else if (dev->type && dev->type->pm)
 417                 callback = dev->type->pm->runtime_suspend;
 418         else if (dev->class && dev->class->pm)
 419                 callback = dev->class->pm->runtime_suspend;
 420         else if (dev->bus && dev->bus->pm)
 421                 callback = dev->bus->pm->runtime_suspend;
 422         else
 423                 callback = NULL;
 424
 425         if (!callback && dev->driver && dev->driver->pm)
 426                 callback = dev->driver->pm->runtime_suspend;
 427
 428         retval = rpm_callback(callback, dev);
 429         if (retval)
 430                 goto fail;
 431
 432  no_callback:
 433         __update_runtime_status(dev, RPM_SUSPENDED);
 434         pm_runtime_deactivate_timer(dev);
 435
 436         if (dev->parent) {
 437                 parent = dev->parent;
 438                 atomic_add_unless(&parent->power.child_count, -1, 0);
 439         }
 440         wake_up_all(&dev->power.wait_queue);
 441
 442         if (dev->power.deferred_resume) {
 443                 rpm_resume(dev, 0);
 444                 retval = -EAGAIN;
 445                 goto out;
 446         }
 447
 448         /* Maybe the parent is now able to suspend. */
 449         if (parent && !parent->power.ignore_children && !dev->power.irq_safe) {
 450                 spin_unlock(&dev->power.lock);
 451
 452                 spin_lock(&parent->power.lock);
 453                 rpm_idle(parent, RPM_ASYNC);
 454                 spin_unlock(&parent->power.lock);
 455
 456                 spin_lock(&dev->power.lock);
 457         }
 458
 459  out:
 460         trace_rpm_return_int(dev, _THIS_IP_, retval);
 461
 462         return retval;
 463
 464  fail:
 465         __update_runtime_status(dev, RPM_ACTIVE);
 466         dev->power.deferred_resume = false;
 467         wake_up_all(&dev->power.wait_queue);
 468
 469         if (retval == -EAGAIN || retval == -EBUSY) {
 470                 dev->power.runtime_error = 0;
 471
 472                 /*
 473                  * If the callback routine failed an autosuspend, and
 474                  * if the last_busy time has been updated so that there
 475                  * is a new autosuspend expiration time, automatically
 476                  * reschedule another autosuspend.
 477                  */
 478                 if ((rpmflags & RPM_AUTO) &&
 479                     pm_runtime_autosuspend_expiration(dev) != 0)
 480                         goto repeat;
 481         } else {
 482                 pm_runtime_cancel_pending(dev);
 483         }
 484         goto out;
 485 }
 486
 487 /**
 488  * rpm_resume - Carry out runtime resume of given device.
 489  * @dev: Device to resume.
 490  * @rpmflags: Flag bits.
 491  *
 492  * Check if the device's runtime PM status allows it to be resumed.  Cancel
 493  * any scheduled or pending requests.  If another resume has been started
 494  * earlier, either return immediately or wait for it to finish, depending on the
 495  * RPM_NOWAIT and RPM_ASYNC flags.  Similarly, if there's a suspend running in
 496  * parallel with this function, either tell the other process to resume after
 497  * suspending (deferred_resume) or wait for it to finish.  If the RPM_ASYNC
 498  * flag is set then queue a resume request; otherwise run the
 499  * ->runtime_resume() callback directly.  Queue an idle notification for the
 500  * device if the resume succeeded.
 501  *
 502  * This function must be called under dev->power.lock with interrupts disabled.
 503  */
 504 static int rpm_resume(struct device *dev, int rpmflags)
 505         __releases(&dev->power.lock) __acquires(&dev->power.lock)
 506 {
 507         int (*callback)(struct device *);
 508         struct device *parent = NULL;
 509         int retval = 0;
 510
 511         trace_rpm_resume(dev, rpmflags);
 512
 513  repeat:
 514         if (dev->power.runtime_error)
 515                 retval = -EINVAL;
 516         else if (dev->power.disable_depth > 0)
 517                 retval = -EACCES;
 518         if (retval)
 519                 goto out;
 520
 521         /*
 522          * Other scheduled or pending requests need to be canceled.  Small
 523          * optimization: If an autosuspend timer is running, leave it running
 524          * rather than cancelling it now only to restart it again in the near
 525          * future.
 526          */
 527         dev->power.request = RPM_REQ_NONE;
 528         if (!dev->power.timer_autosuspends)
 529                 pm_runtime_deactivate_timer(dev);
 530
 531         if (dev->power.runtime_status == RPM_ACTIVE) {
 532                 retval = 1;
 533                 goto out;
 534         }
 535
 536         if (dev->power.runtime_status == RPM_RESUMING
 537             || dev->power.runtime_status == RPM_SUSPENDING) {
 538                 DEFINE_WAIT(wait);
 539
 540                 if (rpmflags & (RPM_ASYNC | RPM_NOWAIT)) {
 541                         if (dev->power.runtime_status == RPM_SUSPENDING)
 542                                 dev->power.deferred_resume = true;
 543                         else
 544                                 retval = -EINPROGRESS;
 545                         goto out;
 546                 }
 547
 548                 if (dev->power.irq_safe) {
 549                         spin_unlock(&dev->power.lock);
 550
 551                         cpu_relax();
 552
 553                         spin_lock(&dev->power.lock);
 554                         goto repeat;
 555                 }
 556
 557                 /* Wait for the operation carried out in parallel with us. */
 558                 for (;;) {
 559                         prepare_to_wait(&dev->power.wait_queue, &wait,
 560                                         TASK_UNINTERRUPTIBLE);
 561                         if (dev->power.runtime_status != RPM_RESUMING
 562                             && dev->power.runtime_status != RPM_SUSPENDING)
 563                                 break;
 564
 565                         spin_unlock_irq(&dev->power.lock);
 566
 567                         schedule();
 568
 569                         spin_lock_irq(&dev->power.lock);
 570                 }
 571                 finish_wait(&dev->power.wait_queue, &wait);
 572                 goto repeat;
 573         }
 574
 575         /*
 576          * See if we can skip waking up the parent.  This is safe only if
 577          * power.no_callbacks is set, because otherwise we don't know whether
 578          * the resume will actually succeed.
 579          */
 580         if (dev->power.no_callbacks && !parent && dev->parent) {
 581                 spin_lock_nested(&dev->parent->power.lock, SINGLE_DEPTH_NESTING);
 582                 if (dev->parent->power.disable_depth > 0
 583                     || dev->parent->power.ignore_children
 584                     || dev->parent->power.runtime_status == RPM_ACTIVE) {
 585                         atomic_inc(&dev->parent->power.child_count);
 586                         spin_unlock(&dev->parent->power.lock);
 587                         goto no_callback;       /* Assume success. */
 588                 }
 589                 spin_unlock(&dev->parent->power.lock);
 590         }
 591
 592         /* Carry out an asynchronous or a synchronous resume. */
 593         if (rpmflags & RPM_ASYNC) {
 594                 dev->power.request = RPM_REQ_RESUME;
 595                 if (!dev->power.request_pending) {
 596                         dev->power.request_pending = true;
 597                         queue_work(pm_wq, &dev->power.work);
 598                 }
 599                 retval = 0;
 600                 goto out;
 601         }
 602
 603         if (!parent && dev->parent) {
 604                 /*
 605                  * Increment the parent's usage counter and resume it if
 606                  * necessary.  Not needed if dev is irq-safe; then the
 607                  * parent is permanently resumed.
 608                  */
 609                 parent = dev->parent;
 610                 if (dev->power.irq_safe)
 611                         goto skip_parent;
 612                 spin_unlock(&dev->power.lock);
 613
 614                 pm_runtime_get_noresume(parent);
 615
 616                 spin_lock(&parent->power.lock);
 617                 /*
 618                  * We can resume if the parent's runtime PM is disabled or it
 619                  * is set to ignore children.
 620                  */
 621                 if (!parent->power.disable_depth
 622                     && !parent->power.ignore_children) {
 623                         rpm_resume(parent, 0);
 624                         if (parent->power.runtime_status != RPM_ACTIVE)
 625                                 retval = -EBUSY;
 626                 }
 627                 spin_unlock(&parent->power.lock);
 628
 629                 spin_lock(&dev->power.lock);
 630                 if (retval)
 631                         goto out;
 632                 goto repeat;
 633         }
 634  skip_parent:
 635
 636         if (dev->power.no_callbacks)
 637                 goto no_callback;       /* Assume success. */
 638
 639         __update_runtime_status(dev, RPM_RESUMING);
 640
 641         if (dev->pm_domain)
 642                 callback = dev->pm_domain->ops.runtime_resume;
 643         else if (dev->type && dev->type->pm)
 644                 callback = dev->type->pm->runtime_resume;
 645         else if (dev->class && dev->class->pm)
 646                 callback = dev->class->pm->runtime_resume;
 647         else if (dev->bus && dev->bus->pm)
 648                 callback = dev->bus->pm->runtime_resume;
 649         else
 650                 callback = NULL;
 651
 652         if (!callback && dev->driver && dev->driver->pm)
 653                 callback = dev->driver->pm->runtime_resume;
 654
 655         retval = rpm_callback(callback, dev);
 656         if (retval) {
 657                 __update_runtime_status(dev, RPM_SUSPENDED);
 658                 pm_runtime_cancel_pending(dev);
 659         } else {
 660  no_callback:
 661                 __update_runtime_status(dev, RPM_ACTIVE);
 662                 if (parent)
 663                         atomic_inc(&parent->power.child_count);
 664         }
 665         wake_up_all(&dev->power.wait_queue);
 666
 667         if (!retval)
 668                 rpm_idle(dev, RPM_ASYNC);
 669
 670  out:
 671         if (parent && !dev->power.irq_safe) {
 672                 spin_unlock_irq(&dev->power.lock);
 673
 674                 pm_runtime_put(parent);
 675
 676                 spin_lock_irq(&dev->power.lock);
 677         }
 678
 679         trace_rpm_return_int(dev, _THIS_IP_, retval);
 680
 681         return retval;
 682 }
 683
 684 /**
 685  * pm_runtime_work - Universal runtime PM work function.
 686  * @work: Work structure used for scheduling the execution of this function.
 687  *
 688  * Use @work to get the device object the work is to be done for, determine what
 689  * is to be done and execute the appropriate runtime PM function.
 690  */
 691 static void pm_runtime_work(struct work_struct *work)
 692 {
 693         struct device *dev = container_of(work, struct device, power.work);
 694         enum rpm_request req;
 695
 696         spin_lock_irq(&dev->power.lock);
 697
 698         if (!dev->power.request_pending)
 699                 goto out;
 700
 701         req = dev->power.request;
 702         dev->power.request = RPM_REQ_NONE;
 703         dev->power.request_pending = false;
 704
 705         switch (req) {
 706         case RPM_REQ_NONE:
 707                 break;
 708         case RPM_REQ_IDLE:
 709                 rpm_idle(dev, RPM_NOWAIT);
 710                 break;
 711         case RPM_REQ_SUSPEND:
 712                 rpm_suspend(dev, RPM_NOWAIT);
 713                 break;
 714         case RPM_REQ_AUTOSUSPEND:
 715                 rpm_suspend(dev, RPM_NOWAIT | RPM_AUTO);
 716                 break;
 717         case RPM_REQ_RESUME:
 718                 rpm_resume(dev, RPM_NOWAIT);
 719                 break;
 720         }
 721
 722  out:
 723         spin_unlock_irq(&dev->power.lock);
 724 }
 725
 726 /**
 727  * pm_suspend_timer_fn - Timer function for pm_schedule_suspend().
 728  * @data: Device pointer passed by pm_schedule_suspend().
 729  *
 730  * Check if the time is right and queue a suspend request.
 731  */
 732 static void pm_suspend_timer_fn(unsigned long data)
 733 {
 734         struct device *dev = (struct device *)data;
 735         unsigned long flags;
 736         unsigned long expires;
 737
 738         spin_lock_irqsave(&dev->power.lock, flags);
 739
 740         expires = dev->power.timer_expires;
 741         /* If 'expire' is after 'jiffies' we've been called too early. */
 742         if (expires > 0 && !time_after(expires, jiffies)) {
 743                 dev->power.timer_expires = 0;
 744                 rpm_suspend(dev, dev->power.timer_autosuspends ?
 745                     (RPM_ASYNC | RPM_AUTO) : RPM_ASYNC);
 746         }
 747
 748         spin_unlock_irqrestore(&dev->power.lock, flags);
 749 }
 750
 751 /**
 752  * pm_schedule_suspend - Set up a timer to submit a suspend request in future.
 753  * @dev: Device to suspend.
 754  * @delay: Time to wait before submitting a suspend request, in milliseconds.
 755  */
 756 int pm_schedule_suspend(struct device *dev, unsigned int delay)
 757 {
 758         unsigned long flags;
 759         int retval;
 760
 761         spin_lock_irqsave(&dev->power.lock, flags);
 762
 763         if (!delay) {
 764                 retval = rpm_suspend(dev, RPM_ASYNC);
 765                 goto out;
 766         }
 767
 768         retval = rpm_check_suspend_allowed(dev);
 769         if (retval)
 770                 goto out;
 771
 772         /* Other scheduled or pending requests need to be canceled. */
 773         pm_runtime_cancel_pending(dev);
 774
 775         dev->power.timer_expires = jiffies + msecs_to_jiffies(delay);
 776         dev->power.timer_expires += !dev->power.timer_expires;
 777         dev->power.timer_autosuspends = 0;
 778         mod_timer(&dev->power.suspend_timer, dev->power.timer_expires);
 779
 780  out:
 781         spin_unlock_irqrestore(&dev->power.lock, flags);
 782
 783         return retval;
 784 }
 785 EXPORT_SYMBOL_GPL(pm_schedule_suspend);
 786
 787 /**
 788  * __pm_runtime_idle - Entry point for runtime idle operations.
 789  * @dev: Device to send idle notification for.
 790  * @rpmflags: Flag bits.
 791  *
 792  * If the RPM_GET_PUT flag is set, decrement the device's usage count and
 793  * return immediately if it is larger than zero.  Then carry out an idle
 794  * notification, either synchronous or asynchronous.
 795  *
 796  * This routine may be called in atomic context if the RPM_ASYNC flag is set,
 797  * or if pm_runtime_irq_safe() has been called.
 798  */
 799 int __pm_runtime_idle(struct device *dev, int rpmflags)
 800 {
 801         unsigned long flags;
 802         int retval;
 803
 804         might_sleep_if(!(rpmflags & RPM_ASYNC) && !dev->power.irq_safe);
 805
 806         if (rpmflags & RPM_GET_PUT) {
 807                 if (!atomic_dec_and_test(&dev->power.usage_count))
 808                         return 0;
 809         }
 810
 811         spin_lock_irqsave(&dev->power.lock, flags);
 812         retval = rpm_idle(dev, rpmflags);
 813         spin_unlock_irqrestore(&dev->power.lock, flags);
 814
 815         return retval;
 816 }
 817 EXPORT_SYMBOL_GPL(__pm_runtime_idle);
 818
 819 /**
 820  * __pm_runtime_suspend - Entry point for runtime put/suspend operations.
 821  * @dev: Device to suspend.
 822  * @rpmflags: Flag bits.
 823  *
 824  * If the RPM_GET_PUT flag is set, decrement the device's usage count and
 825  * return immediately if it is larger than zero.  Then carry out a suspend,
 826  * either synchronous or asynchronous.
 827  *
 828  * This routine may be called in atomic context if the RPM_ASYNC flag is set,
 829  * or if pm_runtime_irq_safe() has been called.
 830  */
 831 int __pm_runtime_suspend(struct device *dev, int rpmflags)
 832 {
 833         unsigned long flags;
 834         int retval;
 835
 836         might_sleep_if(!(rpmflags & RPM_ASYNC) && !dev->power.irq_safe);
 837
 838         if (rpmflags & RPM_GET_PUT) {
 839                 if (!atomic_dec_and_test(&dev->power.usage_count))
 840                         return 0;
 841         }
 842
 843         spin_lock_irqsave(&dev->power.lock, flags);
 844         retval = rpm_suspend(dev, rpmflags);
 845         spin_unlock_irqrestore(&dev->power.lock, flags);
 846
 847         return retval;
 848 }
 849 EXPORT_SYMBOL_GPL(__pm_runtime_suspend);
 850
 851 /**
 852  * __pm_runtime_resume - Entry point for runtime resume operations.
 853  * @dev: Device to resume.
 854  * @rpmflags: Flag bits.
 855  *
 856  * If the RPM_GET_PUT flag is set, increment the device's usage count.  Then
 857  * carry out a resume, either synchronous or asynchronous.
 858  *
 859  * This routine may be called in atomic context if the RPM_ASYNC flag is set,
 860  * or if pm_runtime_irq_safe() has been called.
 861  */
 862 int __pm_runtime_resume(struct device *dev, int rpmflags)
 863 {
 864         unsigned long flags;
 865         int retval;
 866
 867         might_sleep_if(!(rpmflags & RPM_ASYNC) && !dev->power.irq_safe);
 868
 869         if (rpmflags & RPM_GET_PUT)
 870                 atomic_inc(&dev->power.usage_count);
 871
 872         spin_lock_irqsave(&dev->power.lock, flags);
 873         retval = rpm_resume(dev, rpmflags);
 874         spin_unlock_irqrestore(&dev->power.lock, flags);
 875
 876         return retval;
 877 }
 878 EXPORT_SYMBOL_GPL(__pm_runtime_resume);
 879
 880 /**
 881  * __pm_runtime_set_status - Set runtime PM status of a device.
 882  * @dev: Device to handle.
 883  * @status: New runtime PM status of the device.
 884  *
 885  * If runtime PM of the device is disabled or its power.runtime_error field is
 886  * different from zero, the status may be changed either to RPM_ACTIVE, or to
 887  * RPM_SUSPENDED, as long as that reflects the actual state of the device.
 888  * However, if the device has a parent and the parent is not active, and the
 889  * parent's power.ignore_children flag is unset, the device's status cannot be
 890  * set to RPM_ACTIVE, so -EBUSY is returned in that case.
 891  *
 892  * If successful, __pm_runtime_set_status() clears the power.runtime_error field
 893  * and the device parent's counter of unsuspended children is modified to
 894  * reflect the new status.  If the new status is RPM_SUSPENDED, an idle
 895  * notification request for the parent is submitted.
 896  */
 897 int __pm_runtime_set_status(struct device *dev, unsigned int status)
 898 {
 899         struct device *parent = dev->parent;
 900         unsigned long flags;
 901         bool notify_parent = false;
 902         int error = 0;
 903
 904         if (status != RPM_ACTIVE && status != RPM_SUSPENDED)
 905                 return -EINVAL;
 906
 907         spin_lock_irqsave(&dev->power.lock, flags);
 908
 909         if (!dev->power.runtime_error && !dev->power.disable_depth) {
 910                 error = -EAGAIN;
 911                 goto out;
 912         }
 913
 914         if (dev->power.runtime_status == status)
 915                 goto out_set;
 916
 917         if (status == RPM_SUSPENDED) {
 918                 /* It always is possible to set the status to 'suspended'. */
 919                 if (parent) {
 920                         atomic_add_unless(&parent->power.child_count, -1, 0);
 921                         notify_parent = !parent->power.ignore_children;
 922                 }
 923                 goto out_set;
 924         }
 925
 926         if (parent) {
 927                 spin_lock_nested(&parent->power.lock, SINGLE_DEPTH_NESTING);
 928
 929                 /*
 930                  * It is invalid to put an active child under a parent that is
 931                  * not active, has runtime PM enabled and the
 932                  * 'power.ignore_children' flag unset.
 933                  */
 934                 if (!parent->power.disable_depth
 935                     && !parent->power.ignore_children
 936                     && parent->power.runtime_status != RPM_ACTIVE)
 937                         error = -EBUSY;
 938                 else if (dev->power.runtime_status == RPM_SUSPENDED)
 939                         atomic_inc(&parent->power.child_count);
 940
 941                 spin_unlock(&parent->power.lock);
 942
 943                 if (error)
 944                         goto out;
 945         }
 946
 947  out_set:
 948         __update_runtime_status(dev, status);
 949         dev->power.runtime_error = 0;
 950  out:
 951         spin_unlock_irqrestore(&dev->power.lock, flags);
 952
 953         if (notify_parent)
 954                 pm_request_idle(parent);
 955
 956         return error;
 957 }
 958 EXPORT_SYMBOL_GPL(__pm_runtime_set_status);
 959
 960 /**
 961  * __pm_runtime_barrier - Cancel pending requests and wait for completions.
 962  * @dev: Device to handle.
 963  *
 964  * Flush all pending requests for the device from pm_wq and wait for all
 965  * runtime PM operations involving the device in progress to complete.
 966  *
 967  * Should be called under dev->power.lock with interrupts disabled.
 968  */
 969 static void __pm_runtime_barrier(struct device *dev)
 970 {
 971         pm_runtime_deactivate_timer(dev);
 972
 973         if (dev->power.request_pending) {
 974                 dev->power.request = RPM_REQ_NONE;
 975                 spin_unlock_irq(&dev->power.lock);
 976
 977                 cancel_work_sync(&dev->power.work);
 978
 979                 spin_lock_irq(&dev->power.lock);
 980                 dev->power.request_pending = false;
 981         }
 982
 983         if (dev->power.runtime_status == RPM_SUSPENDING
 984             || dev->power.runtime_status == RPM_RESUMING
 985             || dev->power.idle_notification) {
 986                 DEFINE_WAIT(wait);
 987
 988                 /* Suspend, wake-up or idle notification in progress. */
 989                 for (;;) {
 990                         prepare_to_wait(&dev->power.wait_queue, &wait,
 991                                         TASK_UNINTERRUPTIBLE);
 992                         if (dev->power.runtime_status != RPM_SUSPENDING
 993                             && dev->power.runtime_status != RPM_RESUMING
 994                             && !dev->power.idle_notification)
 995                                 break;
 996                         spin_unlock_irq(&dev->power.lock);
 997
 998                         schedule();
 999
1000                         spin_lock_irq(&dev->power.lock);
1001                 }
1002                 finish_wait(&dev->power.wait_queue, &wait);
1003         }
1004 }
1005
1006 /**
1007  * pm_runtime_barrier - Flush pending requests and wait for completions.
1008  * @dev: Device to handle.
1009  *
1010  * Prevent the device from being suspended by incrementing its usage counter and
1011  * if there's a pending resume request for the device, wake the device up.
1012  * Next, make sure that all pending requests for the device have been flushed
1013  * from pm_wq and wait for all runtime PM operations involving the device in
1014  * progress to complete.
1015  *
1016  * Return value:
1017  * 1, if there was a resume request pending and the device had to be woken up,
1018  * 0, otherwise
1019  */
1020 int pm_runtime_barrier(struct device *dev)
1021 {
1022         int retval = 0;
1023
1024         pm_runtime_get_noresume(dev);
1025         spin_lock_irq(&dev->power.lock);
1026
1027         if (dev->power.request_pending
1028             && dev->power.request == RPM_REQ_RESUME) {
1029                 rpm_resume(dev, 0);
1030                 retval = 1;
1031         }
1032
1033         __pm_runtime_barrier(dev);
1034
1035         spin_unlock_irq(&dev->power.lock);
1036         pm_runtime_put_noidle(dev);
1037
1038         return retval;
1039 }
1040 EXPORT_SYMBOL_GPL(pm_runtime_barrier);
1041
1042 /**
1043  * __pm_runtime_disable - Disable runtime PM of a device.
1044  * @dev: Device to handle.
1045  * @check_resume: If set, check if there's a resume request for the device.
1046  *
1047  * Increment power.disable_depth for the device and if was zero previously,
1048  * cancel all pending runtime PM requests for the device and wait for all
1049  * operations in progress to complete.  The device can be either active or
1050  * suspended after its runtime PM has been disabled.
1051  *
1052  * If @check_resume is set and there's a resume request pending when
1053  * __pm_runtime_disable() is called and power.disable_depth is zero, the
1054  * function will wake up the device before disabling its runtime PM.
1055  */
1056 void __pm_runtime_disable(struct device *dev, bool check_resume)
1057 {
1058         spin_lock_irq(&dev->power.lock);
1059
1060         if (dev->power.disable_depth > 0) {
1061                 dev->power.disable_depth++;
1062                 goto out;
1063         }
1064
1065         /*
1066          * Wake up the device if there's a resume request pending, because that
1067          * means there probably is some I/O to process and disabling runtime PM
1068          * shouldn't prevent the device from processing the I/O.
1069          */
1070         if (check_resume && dev->power.request_pending
1071             && dev->power.request == RPM_REQ_RESUME) {
1072                 /*
1073                  * Prevent suspends and idle notifications from being carried
1074                  * out after we have woken up the device.
1075                  */
1076                 pm_runtime_get_noresume(dev);
1077
1078                 rpm_resume(dev, 0);
1079
1080                 pm_runtime_put_noidle(dev);
1081         }
1082
1083         if (!dev->power.disable_depth++)
1084                 __pm_runtime_barrier(dev);
1085
1086  out:
1087         spin_unlock_irq(&dev->power.lock);
1088 }
1089 EXPORT_SYMBOL_GPL(__pm_runtime_disable);
1090
1091 /**
1092  * pm_runtime_enable - Enable runtime PM of a device.
1093  * @dev: Device to handle.
1094  */
1095 void pm_runtime_enable(struct device *dev)
1096 {
1097         unsigned long flags;
1098
1099         spin_lock_irqsave(&dev->power.lock, flags);
1100
1101         if (dev->power.disable_depth > 0)
1102                 dev->power.disable_depth--;
1103         else
1104                 dev_warn(dev, "Unbalanced %s!\n", __func__);
1105
1106         spin_unlock_irqrestore(&dev->power.lock, flags);
1107 }
1108 EXPORT_SYMBOL_GPL(pm_runtime_enable);
1109
1110 /**
1111  * pm_runtime_forbid - Block runtime PM of a device.
1112  * @dev: Device to handle.
1113  *
1114  * Increase the device's usage count and clear its power.runtime_auto flag,
1115  * so that it cannot be suspended at run time until pm_runtime_allow() is called
1116  * for it.
1117  */
1118 void pm_runtime_forbid(struct device *dev)
1119 {
1120         spin_lock_irq(&dev->power.lock);
1121         if (!dev->power.runtime_auto)
1122                 goto out;
1123
1124         dev->power.runtime_auto = false;
1125         atomic_inc(&dev->power.usage_count);
1126         rpm_resume(dev, 0);
1127
1128  out:
1129         spin_unlock_irq(&dev->power.lock);
1130 }
1131 EXPORT_SYMBOL_GPL(pm_runtime_forbid);
1132
1133 /**
1134  * pm_runtime_allow - Unblock runtime PM of a device.
1135  * @dev: Device to handle.
1136  *
1137  * Decrease the device's usage count and set its power.runtime_auto flag.
1138  */
1139 void pm_runtime_allow(struct device *dev)
1140 {
1141         spin_lock_irq(&dev->power.lock);
1142         if (dev->power.runtime_auto)
1143                 goto out;
1144
1145         dev->power.runtime_auto = true;
1146         if (atomic_dec_and_test(&dev->power.usage_count))
1147                 rpm_idle(dev, RPM_AUTO);
1148
1149  out:
1150         spin_unlock_irq(&dev->power.lock);
1151 }
1152 EXPORT_SYMBOL_GPL(pm_runtime_allow);
1153
1154 /**
1155  * pm_runtime_no_callbacks - Ignore runtime PM callbacks for a device.
1156  * @dev: Device to handle.
1157  *
1158  * Set the power.no_callbacks flag, which tells the PM core that this
1159  * device is power-managed through its parent and has no runtime PM
1160  * callbacks of its own.  The runtime sysfs attributes will be removed.
1161  */
1162 void pm_runtime_no_callbacks(struct device *dev)
1163 {
1164         spin_lock_irq(&dev->power.lock);
1165         dev->power.no_callbacks = 1;
1166         spin_unlock_irq(&dev->power.lock);
1167         if (device_is_registered(dev))
1168                 rpm_sysfs_remove(dev);
1169 }
1170 EXPORT_SYMBOL_GPL(pm_runtime_no_callbacks);
1171
1172 /**
1173  * pm_runtime_irq_safe - Leave interrupts disabled during callbacks.
1174  * @dev: Device to handle
1175  *
1176  * Set the power.irq_safe flag, which tells the PM core that the
1177  * ->runtime_suspend() and ->runtime_resume() callbacks for this device should
1178  * always be invoked with the spinlock held and interrupts disabled.  It also
1179  * causes the parent's usage counter to be permanently incremented, preventing
1180  * the parent from runtime suspending -- otherwise an irq-safe child might have
1181  * to wait for a non-irq-safe parent.
1182  */
1183 void pm_runtime_irq_safe(struct device *dev)
1184 {
1185         if (dev->parent)
1186                 pm_runtime_get_sync(dev->parent);
1187         spin_lock_irq(&dev->power.lock);
1188         dev->power.irq_safe = 1;
1189         spin_unlock_irq(&dev->power.lock);
1190 }
1191 EXPORT_SYMBOL_GPL(pm_runtime_irq_safe);
1192
1193 /**
1194  * update_autosuspend - Handle a change to a device's autosuspend settings.
1195  * @dev: Device to handle.
1196  * @old_delay: The former autosuspend_delay value.
1197  * @old_use: The former use_autosuspend value.
1198  *
1199  * Prevent runtime suspend if the new delay is negative and use_autosuspend is
1200  * set; otherwise allow it.  Send an idle notification if suspends are allowed.
1201  *
1202  * This function must be called under dev->power.lock with interrupts disabled.
1203  */
1204 static void update_autosuspend(struct device *dev, int old_delay, int old_use)
1205 {
1206         int delay = dev->power.autosuspend_delay;
1207
1208         /* Should runtime suspend be prevented now? */
1209         if (dev->power.use_autosuspend && delay < 0) {
1210
1211                 /* If it used to be allowed then prevent it. */
1212                 if (!old_use || old_delay >= 0) {
1213                         atomic_inc(&dev->power.usage_count);
1214                         rpm_resume(dev, 0);
1215                 }
1216         }
1217
1218         /* Runtime suspend should be allowed now. */
1219         else {
1220
1221                 /* If it used to be prevented then allow it. */
1222                 if (old_use && old_delay < 0)
1223                         atomic_dec(&dev->power.usage_count);
1224
1225                 /* Maybe we can autosuspend now. */
1226                 rpm_idle(dev, RPM_AUTO);
1227         }
1228 }
1229
1230 /**
1231  * pm_runtime_set_autosuspend_delay - Set a device's autosuspend_delay value.
1232  * @dev: Device to handle.
1233  * @delay: Value of the new delay in milliseconds.
1234  *
1235  * Set the device's power.autosuspend_delay value.  If it changes to negative
1236  * and the power.use_autosuspend flag is set, prevent runtime suspends.  If it
1237  * changes the other way, allow runtime suspends.
1238  */
1239 void pm_runtime_set_autosuspend_delay(struct device *dev, int delay)
1240 {
1241         int old_delay, old_use;
1242
1243         spin_lock_irq(&dev->power.lock);
1244         old_delay = dev->power.autosuspend_delay;
1245         old_use = dev->power.use_autosuspend;
1246         dev->power.autosuspend_delay = delay;
1247         update_autosuspend(dev, old_delay, old_use);
1248         spin_unlock_irq(&dev->power.lock);
1249 }
1250 EXPORT_SYMBOL_GPL(pm_runtime_set_autosuspend_delay);
1251
1252 /**
1253  * __pm_runtime_use_autosuspend - Set a device's use_autosuspend flag.
1254  * @dev: Device to handle.
1255  * @use: New value for use_autosuspend.
1256  *
1257  * Set the device's power.use_autosuspend flag, and allow or prevent runtime
1258  * suspends as needed.
1259  */
1260 void __pm_runtime_use_autosuspend(struct device *dev, bool use)
1261 {
1262         int old_delay, old_use;
1263
1264         spin_lock_irq(&dev->power.lock);
1265         old_delay = dev->power.autosuspend_delay;
1266         old_use = dev->power.use_autosuspend;
1267         dev->power.use_autosuspend = use;
1268         update_autosuspend(dev, old_delay, old_use);
1269         spin_unlock_irq(&dev->power.lock);
1270 }
1271 EXPORT_SYMBOL_GPL(__pm_runtime_use_autosuspend);
1272
1273 /**
1274  * pm_runtime_init - Initialize runtime PM fields in given device object.
1275  * @dev: Device object to initialize.
1276  */
1277 void pm_runtime_init(struct device *dev)
1278 {
1279         dev->power.runtime_status = RPM_SUSPENDED;
1280         dev->power.idle_notification = false;
1281
1282         dev->power.disable_depth = 1;
1283         atomic_set(&dev->power.usage_count, 0);
1284
1285         dev->power.runtime_error = 0;
1286
1287         atomic_set(&dev->power.child_count, 0);
1288         pm_suspend_ignore_children(dev, false);
1289         dev->power.runtime_auto = true;
1290
1291         dev->power.request_pending = false;
1292         dev->power.request = RPM_REQ_NONE;
1293         dev->power.deferred_resume = false;
1294         dev->power.accounting_timestamp = jiffies;
1295         INIT_WORK(&dev->power.work, pm_runtime_work);
1296
1297         dev->power.timer_expires = 0;
1298         setup_timer(&dev->power.suspend_timer, pm_suspend_timer_fn,
1299                         (unsigned long)dev);
1300
1301         init_waitqueue_head(&dev->power.wait_queue);
1302 }
1303
1304 /**
1305  * pm_runtime_remove - Prepare for removing a device from device hierarchy.
1306  * @dev: Device object being removed from device hierarchy.
1307  */
1308 void pm_runtime_remove(struct device *dev)
1309 {
1310         __pm_runtime_disable(dev, false);
1311
1312         /* Change the status back to 'suspended' to match the initial status. */
1313         if (dev->power.runtime_status == RPM_ACTIVE)
1314                 pm_runtime_set_suspended(dev);
1315         if (dev->power.irq_safe && dev->parent)
1316                 pm_runtime_put_sync(dev->parent);
1317 }