Commit | Line | Data |
---|---|---|
5e928f77 | 1 | /* |
62052ab1 | 2 | * drivers/base/power/runtime.c - Helper functions for device runtime PM |
5e928f77 RW |
3 | * |
4 | * Copyright (c) 2009 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc. | |
1bfee5bc | 5 | * Copyright (C) 2010 Alan Stern <stern@rowland.harvard.edu> |
5e928f77 RW |
6 | * |
7 | * This file is released under the GPLv2. | |
8 | */ | |
9 | ||
10 | #include <linux/sched.h> | |
1b6bc32f | 11 | #include <linux/export.h> |
5e928f77 | 12 | #include <linux/pm_runtime.h> |
4990d4fe | 13 | #include <linux/pm_wakeirq.h> |
c3dc2f14 | 14 | #include <trace/events/rpm.h> |
7490e442 | 15 | #include "power.h" |
5e928f77 | 16 | |
dbcd2d72 | 17 | typedef int (*pm_callback_t)(struct device *); |
5f59df79 | 18 | |
dbcd2d72 | 19 | static pm_callback_t __rpm_get_callback(struct device *dev, size_t cb_offset) |
5f59df79 | 20 | { |
dbcd2d72 AH |
21 | pm_callback_t cb; |
22 | const struct dev_pm_ops *ops; | |
23 | ||
24 | if (dev->pm_domain) | |
25 | ops = &dev->pm_domain->ops; | |
26 | else if (dev->type && dev->type->pm) | |
27 | ops = dev->type->pm; | |
28 | else if (dev->class && dev->class->pm) | |
29 | ops = dev->class->pm; | |
30 | else if (dev->bus && dev->bus->pm) | |
31 | ops = dev->bus->pm; | |
32 | else | |
33 | ops = NULL; | |
34 | ||
35 | if (ops) | |
36 | cb = *(pm_callback_t *)((void *)ops + cb_offset); | |
37 | else | |
38 | cb = NULL; | |
39 | ||
40 | if (!cb && dev->driver && dev->driver->pm) | |
41 | cb = *(pm_callback_t *)((void *)dev->driver->pm + cb_offset); | |
42 | ||
43 | return cb; | |
5f59df79 UH |
44 | } |
45 | ||
dbcd2d72 AH |
46 | #define RPM_GET_CALLBACK(dev, callback) \ |
47 | __rpm_get_callback(dev, offsetof(struct dev_pm_ops, callback)) | |
48 | ||
140a6c94 | 49 | static int rpm_resume(struct device *dev, int rpmflags); |
7490e442 | 50 | static int rpm_suspend(struct device *dev, int rpmflags); |
5e928f77 | 51 | |
4769373c AS |
52 | /** |
53 | * update_pm_runtime_accounting - Update the time accounting of power states | |
54 | * @dev: Device to update the accounting for | |
55 | * | |
56 | * In order to be able to have time accounting of the various power states | |
57 | * (as used by programs such as PowerTOP to show the effectiveness of runtime | |
58 | * PM), we need to track the time spent in each state. | |
59 | * update_pm_runtime_accounting must be called each time before the | |
60 | * runtime_status field is updated, to account the time in the old state | |
61 | * correctly. | |
62 | */ | |
63 | void update_pm_runtime_accounting(struct device *dev) | |
64 | { | |
65 | unsigned long now = jiffies; | |
def0c0a3 | 66 | unsigned long delta; |
4769373c AS |
67 | |
68 | delta = now - dev->power.accounting_timestamp; | |
69 | ||
4769373c AS |
70 | dev->power.accounting_timestamp = now; |
71 | ||
72 | if (dev->power.disable_depth > 0) | |
73 | return; | |
74 | ||
75 | if (dev->power.runtime_status == RPM_SUSPENDED) | |
76 | dev->power.suspended_jiffies += delta; | |
77 | else | |
78 | dev->power.active_jiffies += delta; | |
79 | } | |
80 | ||
81 | static void __update_runtime_status(struct device *dev, enum rpm_status status) | |
82 | { | |
83 | update_pm_runtime_accounting(dev); | |
84 | dev->power.runtime_status = status; | |
85 | } | |
86 | ||
5e928f77 RW |
87 | /** |
88 | * pm_runtime_deactivate_timer - Deactivate given device's suspend timer. | |
89 | * @dev: Device to handle. | |
90 | */ | |
91 | static void pm_runtime_deactivate_timer(struct device *dev) | |
92 | { | |
93 | if (dev->power.timer_expires > 0) { | |
94 | del_timer(&dev->power.suspend_timer); | |
95 | dev->power.timer_expires = 0; | |
96 | } | |
97 | } | |
98 | ||
99 | /** | |
100 | * pm_runtime_cancel_pending - Deactivate suspend timer and cancel requests. | |
101 | * @dev: Device to handle. | |
102 | */ | |
103 | static void pm_runtime_cancel_pending(struct device *dev) | |
104 | { | |
105 | pm_runtime_deactivate_timer(dev); | |
106 | /* | |
107 | * In case there's a request pending, make sure its work function will | |
108 | * return without doing anything. | |
109 | */ | |
110 | dev->power.request = RPM_REQ_NONE; | |
111 | } | |
112 | ||
15bcb91d AS |
113 | /* |
114 | * pm_runtime_autosuspend_expiration - Get a device's autosuspend-delay expiration time. | |
115 | * @dev: Device to handle. | |
116 | * | |
117 | * Compute the autosuspend-delay expiration time based on the device's | |
118 | * power.last_busy time. If the delay has already expired or is disabled | |
119 | * (negative) or the power.use_autosuspend flag isn't set, return 0. | |
120 | * Otherwise return the expiration time in jiffies (adjusted to be nonzero). | |
121 | * | |
122 | * This function may be called either with or without dev->power.lock held. | |
123 | * Either way it can be racy, since power.last_busy may be updated at any time. | |
124 | */ | |
125 | unsigned long pm_runtime_autosuspend_expiration(struct device *dev) | |
126 | { | |
127 | int autosuspend_delay; | |
128 | long elapsed; | |
129 | unsigned long last_busy; | |
130 | unsigned long expires = 0; | |
131 | ||
132 | if (!dev->power.use_autosuspend) | |
133 | goto out; | |
134 | ||
135 | autosuspend_delay = ACCESS_ONCE(dev->power.autosuspend_delay); | |
136 | if (autosuspend_delay < 0) | |
137 | goto out; | |
138 | ||
139 | last_busy = ACCESS_ONCE(dev->power.last_busy); | |
140 | elapsed = jiffies - last_busy; | |
141 | if (elapsed < 0) | |
142 | goto out; /* jiffies has wrapped around. */ | |
143 | ||
144 | /* | |
145 | * If the autosuspend_delay is >= 1 second, align the timer by rounding | |
146 | * up to the nearest second. | |
147 | */ | |
148 | expires = last_busy + msecs_to_jiffies(autosuspend_delay); | |
149 | if (autosuspend_delay >= 1000) | |
150 | expires = round_jiffies(expires); | |
151 | expires += !expires; | |
152 | if (elapsed >= expires - last_busy) | |
153 | expires = 0; /* Already expired. */ | |
154 | ||
155 | out: | |
156 | return expires; | |
157 | } | |
158 | EXPORT_SYMBOL_GPL(pm_runtime_autosuspend_expiration); | |
159 | ||
e823407f ML |
160 | static int dev_memalloc_noio(struct device *dev, void *data) |
161 | { | |
162 | return dev->power.memalloc_noio; | |
163 | } | |
164 | ||
165 | /* | |
166 | * pm_runtime_set_memalloc_noio - Set a device's memalloc_noio flag. | |
167 | * @dev: Device to handle. | |
168 | * @enable: True for setting the flag and False for clearing the flag. | |
169 | * | |
170 | * Set the flag for all devices in the path from the device to the | |
171 | * root device in the device tree if @enable is true, otherwise clear | |
172 | * the flag for devices in the path whose siblings don't set the flag. | |
173 | * | |
174 | * The function should only be called by block device, or network | |
175 | * device driver for solving the deadlock problem during runtime | |
176 | * resume/suspend: | |
177 | * | |
178 | * If memory allocation with GFP_KERNEL is called inside runtime | |
179 | * resume/suspend callback of any one of its ancestors(or the | |
180 | * block device itself), the deadlock may be triggered inside the | |
181 | * memory allocation since it might not complete until the block | |
182 | * device becomes active and the involed page I/O finishes. The | |
183 | * situation is pointed out first by Alan Stern. Network device | |
184 | * are involved in iSCSI kind of situation. | |
185 | * | |
186 | * The lock of dev_hotplug_mutex is held in the function for handling | |
187 | * hotplug race because pm_runtime_set_memalloc_noio() may be called | |
188 | * in async probe(). | |
189 | * | |
190 | * The function should be called between device_add() and device_del() | |
191 | * on the affected device(block/network device). | |
192 | */ | |
193 | void pm_runtime_set_memalloc_noio(struct device *dev, bool enable) | |
194 | { | |
195 | static DEFINE_MUTEX(dev_hotplug_mutex); | |
196 | ||
197 | mutex_lock(&dev_hotplug_mutex); | |
198 | for (;;) { | |
199 | bool enabled; | |
200 | ||
201 | /* hold power lock since bitfield is not SMP-safe. */ | |
202 | spin_lock_irq(&dev->power.lock); | |
203 | enabled = dev->power.memalloc_noio; | |
204 | dev->power.memalloc_noio = enable; | |
205 | spin_unlock_irq(&dev->power.lock); | |
206 | ||
207 | /* | |
208 | * not need to enable ancestors any more if the device | |
209 | * has been enabled. | |
210 | */ | |
211 | if (enabled && enable) | |
212 | break; | |
213 | ||
214 | dev = dev->parent; | |
215 | ||
216 | /* | |
217 | * clear flag of the parent device only if all the | |
218 | * children don't set the flag because ancestor's | |
219 | * flag was set by any one of the descendants. | |
220 | */ | |
221 | if (!dev || (!enable && | |
222 | device_for_each_child(dev, NULL, | |
223 | dev_memalloc_noio))) | |
224 | break; | |
225 | } | |
226 | mutex_unlock(&dev_hotplug_mutex); | |
227 | } | |
228 | EXPORT_SYMBOL_GPL(pm_runtime_set_memalloc_noio); | |
229 | ||
5e928f77 | 230 | /** |
1bfee5bc AS |
231 | * rpm_check_suspend_allowed - Test whether a device may be suspended. |
232 | * @dev: Device to test. | |
5e928f77 | 233 | */ |
1bfee5bc | 234 | static int rpm_check_suspend_allowed(struct device *dev) |
5e928f77 RW |
235 | { |
236 | int retval = 0; | |
237 | ||
5e928f77 RW |
238 | if (dev->power.runtime_error) |
239 | retval = -EINVAL; | |
632e270e RW |
240 | else if (dev->power.disable_depth > 0) |
241 | retval = -EACCES; | |
242 | else if (atomic_read(&dev->power.usage_count) > 0) | |
5e928f77 | 243 | retval = -EAGAIN; |
62006c17 UH |
244 | else if (!dev->power.ignore_children && |
245 | atomic_read(&dev->power.child_count)) | |
5e928f77 | 246 | retval = -EBUSY; |
1bfee5bc AS |
247 | |
248 | /* Pending resume requests take precedence over suspends. */ | |
249 | else if ((dev->power.deferred_resume | |
78ca7c37 | 250 | && dev->power.runtime_status == RPM_SUSPENDING) |
1bfee5bc AS |
251 | || (dev->power.request_pending |
252 | && dev->power.request == RPM_REQ_RESUME)) | |
253 | retval = -EAGAIN; | |
55d7ec45 RW |
254 | else if (__dev_pm_qos_read_value(dev) < 0) |
255 | retval = -EPERM; | |
1bfee5bc AS |
256 | else if (dev->power.runtime_status == RPM_SUSPENDED) |
257 | retval = 1; | |
258 | ||
259 | return retval; | |
260 | } | |
261 | ||
ad3c36a5 RW |
262 | /** |
263 | * __rpm_callback - Run a given runtime PM callback for a given device. | |
264 | * @cb: Runtime PM callback to run. | |
265 | * @dev: Device to run the callback for. | |
266 | */ | |
267 | static int __rpm_callback(int (*cb)(struct device *), struct device *dev) | |
268 | __releases(&dev->power.lock) __acquires(&dev->power.lock) | |
269 | { | |
270 | int retval; | |
271 | ||
272 | if (dev->power.irq_safe) | |
273 | spin_unlock(&dev->power.lock); | |
274 | else | |
275 | spin_unlock_irq(&dev->power.lock); | |
276 | ||
277 | retval = cb(dev); | |
278 | ||
279 | if (dev->power.irq_safe) | |
280 | spin_lock(&dev->power.lock); | |
281 | else | |
282 | spin_lock_irq(&dev->power.lock); | |
283 | ||
284 | return retval; | |
285 | } | |
286 | ||
1bfee5bc | 287 | /** |
140a6c94 | 288 | * rpm_idle - Notify device bus type if the device can be suspended. |
1bfee5bc AS |
289 | * @dev: Device to notify the bus type about. |
290 | * @rpmflags: Flag bits. | |
291 | * | |
62052ab1 | 292 | * Check if the device's runtime PM status allows it to be suspended. If |
1bfee5bc AS |
293 | * another idle notification has been started earlier, return immediately. If |
294 | * the RPM_ASYNC flag is set then queue an idle-notification request; otherwise | |
d66e6db2 UH |
295 | * run the ->runtime_idle() callback directly. If the ->runtime_idle callback |
296 | * doesn't exist or if it returns 0, call rpm_suspend with the RPM_AUTO flag. | |
1bfee5bc AS |
297 | * |
298 | * This function must be called under dev->power.lock with interrupts disabled. | |
299 | */ | |
140a6c94 | 300 | static int rpm_idle(struct device *dev, int rpmflags) |
1bfee5bc | 301 | { |
71c63122 | 302 | int (*callback)(struct device *); |
1bfee5bc AS |
303 | int retval; |
304 | ||
d7737ce9 | 305 | trace_rpm_idle_rcuidle(dev, rpmflags); |
1bfee5bc AS |
306 | retval = rpm_check_suspend_allowed(dev); |
307 | if (retval < 0) | |
308 | ; /* Conditions are wrong. */ | |
309 | ||
310 | /* Idle notifications are allowed only in the RPM_ACTIVE state. */ | |
311 | else if (dev->power.runtime_status != RPM_ACTIVE) | |
312 | retval = -EAGAIN; | |
313 | ||
314 | /* | |
315 | * Any pending request other than an idle notification takes | |
316 | * precedence over us, except that the timer may be running. | |
317 | */ | |
318 | else if (dev->power.request_pending && | |
319 | dev->power.request > RPM_REQ_IDLE) | |
320 | retval = -EAGAIN; | |
321 | ||
322 | /* Act as though RPM_NOWAIT is always set. */ | |
323 | else if (dev->power.idle_notification) | |
324 | retval = -EINPROGRESS; | |
5e928f77 RW |
325 | if (retval) |
326 | goto out; | |
327 | ||
1bfee5bc AS |
328 | /* Pending requests need to be canceled. */ |
329 | dev->power.request = RPM_REQ_NONE; | |
330 | ||
45f0a85c | 331 | if (dev->power.no_callbacks) |
7490e442 | 332 | goto out; |
7490e442 | 333 | |
1bfee5bc AS |
334 | /* Carry out an asynchronous or a synchronous idle notification. */ |
335 | if (rpmflags & RPM_ASYNC) { | |
336 | dev->power.request = RPM_REQ_IDLE; | |
337 | if (!dev->power.request_pending) { | |
338 | dev->power.request_pending = true; | |
339 | queue_work(pm_wq, &dev->power.work); | |
5e928f77 | 340 | } |
d7737ce9 | 341 | trace_rpm_return_int_rcuidle(dev, _THIS_IP_, 0); |
45f0a85c | 342 | return 0; |
5e928f77 RW |
343 | } |
344 | ||
345 | dev->power.idle_notification = true; | |
346 | ||
dbcd2d72 | 347 | callback = RPM_GET_CALLBACK(dev, runtime_idle); |
35cd133c | 348 | |
ad3c36a5 | 349 | if (callback) |
45f0a85c | 350 | retval = __rpm_callback(callback, dev); |
5e928f77 RW |
351 | |
352 | dev->power.idle_notification = false; | |
353 | wake_up_all(&dev->power.wait_queue); | |
354 | ||
355 | out: | |
d7737ce9 | 356 | trace_rpm_return_int_rcuidle(dev, _THIS_IP_, retval); |
d66e6db2 | 357 | return retval ? retval : rpm_suspend(dev, rpmflags | RPM_AUTO); |
5e928f77 RW |
358 | } |
359 | ||
71c63122 RW |
360 | /** |
361 | * rpm_callback - Run a given runtime PM callback for a given device. | |
362 | * @cb: Runtime PM callback to run. | |
363 | * @dev: Device to run the callback for. | |
364 | */ | |
365 | static int rpm_callback(int (*cb)(struct device *), struct device *dev) | |
71c63122 RW |
366 | { |
367 | int retval; | |
368 | ||
369 | if (!cb) | |
370 | return -ENOSYS; | |
371 | ||
db88175f ML |
372 | if (dev->power.memalloc_noio) { |
373 | unsigned int noio_flag; | |
374 | ||
375 | /* | |
376 | * Deadlock might be caused if memory allocation with | |
377 | * GFP_KERNEL happens inside runtime_suspend and | |
378 | * runtime_resume callbacks of one block device's | |
379 | * ancestor or the block device itself. Network | |
380 | * device might be thought as part of iSCSI block | |
381 | * device, so network device and its ancestor should | |
382 | * be marked as memalloc_noio too. | |
383 | */ | |
384 | noio_flag = memalloc_noio_save(); | |
385 | retval = __rpm_callback(cb, dev); | |
386 | memalloc_noio_restore(noio_flag); | |
387 | } else { | |
388 | retval = __rpm_callback(cb, dev); | |
389 | } | |
71c63122 | 390 | |
71c63122 | 391 | dev->power.runtime_error = retval; |
632e270e | 392 | return retval != -EACCES ? retval : -EIO; |
71c63122 RW |
393 | } |
394 | ||
5e928f77 | 395 | /** |
62052ab1 | 396 | * rpm_suspend - Carry out runtime suspend of given device. |
5e928f77 | 397 | * @dev: Device to suspend. |
3f9af051 | 398 | * @rpmflags: Flag bits. |
5e928f77 | 399 | * |
47d8f0ba ML |
400 | * Check if the device's runtime PM status allows it to be suspended. |
401 | * Cancel a pending idle notification, autosuspend or suspend. If | |
402 | * another suspend has been started earlier, either return immediately | |
403 | * or wait for it to finish, depending on the RPM_NOWAIT and RPM_ASYNC | |
404 | * flags. If the RPM_ASYNC flag is set then queue a suspend request; | |
857b36c7 ML |
405 | * otherwise run the ->runtime_suspend() callback directly. When |
406 | * ->runtime_suspend succeeded, if a deferred resume was requested while | |
407 | * the callback was running then carry it out, otherwise send an idle | |
408 | * notification for its parent (if the suspend succeeded and both | |
409 | * ignore_children of parent->power and irq_safe of dev->power are not set). | |
886486b7 AS |
410 | * If ->runtime_suspend failed with -EAGAIN or -EBUSY, and if the RPM_AUTO |
411 | * flag is set and the next autosuspend-delay expiration time is in the | |
412 | * future, schedule another autosuspend attempt. | |
5e928f77 RW |
413 | * |
414 | * This function must be called under dev->power.lock with interrupts disabled. | |
415 | */ | |
140a6c94 | 416 | static int rpm_suspend(struct device *dev, int rpmflags) |
5e928f77 RW |
417 | __releases(&dev->power.lock) __acquires(&dev->power.lock) |
418 | { | |
71c63122 | 419 | int (*callback)(struct device *); |
5e928f77 | 420 | struct device *parent = NULL; |
1bfee5bc | 421 | int retval; |
5e928f77 | 422 | |
77893577 | 423 | trace_rpm_suspend_rcuidle(dev, rpmflags); |
5e928f77 RW |
424 | |
425 | repeat: | |
1bfee5bc | 426 | retval = rpm_check_suspend_allowed(dev); |
5e928f77 | 427 | |
1bfee5bc AS |
428 | if (retval < 0) |
429 | ; /* Conditions are wrong. */ | |
430 | ||
431 | /* Synchronous suspends are not allowed in the RPM_RESUMING state. */ | |
432 | else if (dev->power.runtime_status == RPM_RESUMING && | |
433 | !(rpmflags & RPM_ASYNC)) | |
5e928f77 | 434 | retval = -EAGAIN; |
1bfee5bc | 435 | if (retval) |
5e928f77 | 436 | goto out; |
5e928f77 | 437 | |
15bcb91d AS |
438 | /* If the autosuspend_delay time hasn't expired yet, reschedule. */ |
439 | if ((rpmflags & RPM_AUTO) | |
440 | && dev->power.runtime_status != RPM_SUSPENDING) { | |
441 | unsigned long expires = pm_runtime_autosuspend_expiration(dev); | |
442 | ||
443 | if (expires != 0) { | |
444 | /* Pending requests need to be canceled. */ | |
445 | dev->power.request = RPM_REQ_NONE; | |
446 | ||
447 | /* | |
448 | * Optimization: If the timer is already running and is | |
449 | * set to expire at or before the autosuspend delay, | |
450 | * avoid the overhead of resetting it. Just let it | |
451 | * expire; pm_suspend_timer_fn() will take care of the | |
452 | * rest. | |
453 | */ | |
454 | if (!(dev->power.timer_expires && time_before_eq( | |
455 | dev->power.timer_expires, expires))) { | |
456 | dev->power.timer_expires = expires; | |
457 | mod_timer(&dev->power.suspend_timer, expires); | |
458 | } | |
459 | dev->power.timer_autosuspends = 1; | |
460 | goto out; | |
461 | } | |
462 | } | |
463 | ||
5e928f77 RW |
464 | /* Other scheduled or pending requests need to be canceled. */ |
465 | pm_runtime_cancel_pending(dev); | |
466 | ||
5e928f77 RW |
467 | if (dev->power.runtime_status == RPM_SUSPENDING) { |
468 | DEFINE_WAIT(wait); | |
469 | ||
1bfee5bc | 470 | if (rpmflags & (RPM_ASYNC | RPM_NOWAIT)) { |
5e928f77 RW |
471 | retval = -EINPROGRESS; |
472 | goto out; | |
473 | } | |
474 | ||
ad3c36a5 RW |
475 | if (dev->power.irq_safe) { |
476 | spin_unlock(&dev->power.lock); | |
477 | ||
478 | cpu_relax(); | |
479 | ||
480 | spin_lock(&dev->power.lock); | |
481 | goto repeat; | |
482 | } | |
483 | ||
5e928f77 RW |
484 | /* Wait for the other suspend running in parallel with us. */ |
485 | for (;;) { | |
486 | prepare_to_wait(&dev->power.wait_queue, &wait, | |
487 | TASK_UNINTERRUPTIBLE); | |
488 | if (dev->power.runtime_status != RPM_SUSPENDING) | |
489 | break; | |
490 | ||
491 | spin_unlock_irq(&dev->power.lock); | |
492 | ||
493 | schedule(); | |
494 | ||
495 | spin_lock_irq(&dev->power.lock); | |
496 | } | |
497 | finish_wait(&dev->power.wait_queue, &wait); | |
498 | goto repeat; | |
499 | } | |
500 | ||
7490e442 AS |
501 | if (dev->power.no_callbacks) |
502 | goto no_callback; /* Assume success. */ | |
503 | ||
1bfee5bc AS |
504 | /* Carry out an asynchronous or a synchronous suspend. */ |
505 | if (rpmflags & RPM_ASYNC) { | |
15bcb91d AS |
506 | dev->power.request = (rpmflags & RPM_AUTO) ? |
507 | RPM_REQ_AUTOSUSPEND : RPM_REQ_SUSPEND; | |
1bfee5bc AS |
508 | if (!dev->power.request_pending) { |
509 | dev->power.request_pending = true; | |
510 | queue_work(pm_wq, &dev->power.work); | |
511 | } | |
512 | goto out; | |
513 | } | |
514 | ||
8d4b9d1b | 515 | __update_runtime_status(dev, RPM_SUSPENDING); |
5e928f77 | 516 | |
dbcd2d72 | 517 | callback = RPM_GET_CALLBACK(dev, runtime_suspend); |
35cd133c | 518 | |
4990d4fe | 519 | dev_pm_enable_wake_irq(dev); |
71c63122 | 520 | retval = rpm_callback(callback, dev); |
00dc9ad1 RW |
521 | if (retval) |
522 | goto fail; | |
886486b7 | 523 | |
7490e442 | 524 | no_callback: |
857b36c7 ML |
525 | __update_runtime_status(dev, RPM_SUSPENDED); |
526 | pm_runtime_deactivate_timer(dev); | |
5e928f77 | 527 | |
857b36c7 ML |
528 | if (dev->parent) { |
529 | parent = dev->parent; | |
530 | atomic_add_unless(&parent->power.child_count, -1, 0); | |
5e928f77 RW |
531 | } |
532 | wake_up_all(&dev->power.wait_queue); | |
533 | ||
534 | if (dev->power.deferred_resume) { | |
58a34de7 | 535 | dev->power.deferred_resume = false; |
140a6c94 | 536 | rpm_resume(dev, 0); |
5e928f77 RW |
537 | retval = -EAGAIN; |
538 | goto out; | |
539 | } | |
540 | ||
c3810c88 | 541 | /* Maybe the parent is now able to suspend. */ |
c7b61de5 | 542 | if (parent && !parent->power.ignore_children && !dev->power.irq_safe) { |
c3810c88 | 543 | spin_unlock(&dev->power.lock); |
5e928f77 | 544 | |
c3810c88 AS |
545 | spin_lock(&parent->power.lock); |
546 | rpm_idle(parent, RPM_ASYNC); | |
547 | spin_unlock(&parent->power.lock); | |
5e928f77 | 548 | |
c3810c88 | 549 | spin_lock(&dev->power.lock); |
5e928f77 RW |
550 | } |
551 | ||
552 | out: | |
77893577 | 553 | trace_rpm_return_int_rcuidle(dev, _THIS_IP_, retval); |
5e928f77 RW |
554 | |
555 | return retval; | |
00dc9ad1 RW |
556 | |
557 | fail: | |
4990d4fe | 558 | dev_pm_disable_wake_irq(dev); |
00dc9ad1 | 559 | __update_runtime_status(dev, RPM_ACTIVE); |
00dc9ad1 | 560 | dev->power.deferred_resume = false; |
f2791d73 AS |
561 | wake_up_all(&dev->power.wait_queue); |
562 | ||
00dc9ad1 RW |
563 | if (retval == -EAGAIN || retval == -EBUSY) { |
564 | dev->power.runtime_error = 0; | |
565 | ||
566 | /* | |
567 | * If the callback routine failed an autosuspend, and | |
568 | * if the last_busy time has been updated so that there | |
569 | * is a new autosuspend expiration time, automatically | |
570 | * reschedule another autosuspend. | |
571 | */ | |
572 | if ((rpmflags & RPM_AUTO) && | |
573 | pm_runtime_autosuspend_expiration(dev) != 0) | |
574 | goto repeat; | |
575 | } else { | |
576 | pm_runtime_cancel_pending(dev); | |
577 | } | |
00dc9ad1 | 578 | goto out; |
5e928f77 RW |
579 | } |
580 | ||
581 | /** | |
62052ab1 | 582 | * rpm_resume - Carry out runtime resume of given device. |
5e928f77 | 583 | * @dev: Device to resume. |
3f9af051 | 584 | * @rpmflags: Flag bits. |
5e928f77 | 585 | * |
62052ab1 | 586 | * Check if the device's runtime PM status allows it to be resumed. Cancel |
1bfee5bc | 587 | * any scheduled or pending requests. If another resume has been started |
25985edc | 588 | * earlier, either return immediately or wait for it to finish, depending on the |
1bfee5bc AS |
589 | * RPM_NOWAIT and RPM_ASYNC flags. Similarly, if there's a suspend running in |
590 | * parallel with this function, either tell the other process to resume after | |
591 | * suspending (deferred_resume) or wait for it to finish. If the RPM_ASYNC | |
592 | * flag is set then queue a resume request; otherwise run the | |
593 | * ->runtime_resume() callback directly. Queue an idle notification for the | |
594 | * device if the resume succeeded. | |
5e928f77 RW |
595 | * |
596 | * This function must be called under dev->power.lock with interrupts disabled. | |
597 | */ | |
140a6c94 | 598 | static int rpm_resume(struct device *dev, int rpmflags) |
5e928f77 RW |
599 | __releases(&dev->power.lock) __acquires(&dev->power.lock) |
600 | { | |
71c63122 | 601 | int (*callback)(struct device *); |
5e928f77 RW |
602 | struct device *parent = NULL; |
603 | int retval = 0; | |
604 | ||
d44c950e | 605 | trace_rpm_resume_rcuidle(dev, rpmflags); |
5e928f77 RW |
606 | |
607 | repeat: | |
1bfee5bc | 608 | if (dev->power.runtime_error) |
5e928f77 | 609 | retval = -EINVAL; |
6f3c77b0 KH |
610 | else if (dev->power.disable_depth == 1 && dev->power.is_suspended |
611 | && dev->power.runtime_status == RPM_ACTIVE) | |
612 | retval = 1; | |
1bfee5bc | 613 | else if (dev->power.disable_depth > 0) |
632e270e | 614 | retval = -EACCES; |
1bfee5bc | 615 | if (retval) |
5e928f77 | 616 | goto out; |
5e928f77 | 617 | |
15bcb91d AS |
618 | /* |
619 | * Other scheduled or pending requests need to be canceled. Small | |
620 | * optimization: If an autosuspend timer is running, leave it running | |
621 | * rather than cancelling it now only to restart it again in the near | |
622 | * future. | |
623 | */ | |
624 | dev->power.request = RPM_REQ_NONE; | |
625 | if (!dev->power.timer_autosuspends) | |
626 | pm_runtime_deactivate_timer(dev); | |
5e928f77 | 627 | |
1bfee5bc | 628 | if (dev->power.runtime_status == RPM_ACTIVE) { |
5e928f77 | 629 | retval = 1; |
5e928f77 | 630 | goto out; |
1bfee5bc | 631 | } |
5e928f77 RW |
632 | |
633 | if (dev->power.runtime_status == RPM_RESUMING | |
634 | || dev->power.runtime_status == RPM_SUSPENDING) { | |
635 | DEFINE_WAIT(wait); | |
636 | ||
1bfee5bc | 637 | if (rpmflags & (RPM_ASYNC | RPM_NOWAIT)) { |
5e928f77 RW |
638 | if (dev->power.runtime_status == RPM_SUSPENDING) |
639 | dev->power.deferred_resume = true; | |
1bfee5bc AS |
640 | else |
641 | retval = -EINPROGRESS; | |
5e928f77 RW |
642 | goto out; |
643 | } | |
644 | ||
ad3c36a5 RW |
645 | if (dev->power.irq_safe) { |
646 | spin_unlock(&dev->power.lock); | |
647 | ||
648 | cpu_relax(); | |
649 | ||
650 | spin_lock(&dev->power.lock); | |
651 | goto repeat; | |
652 | } | |
653 | ||
5e928f77 RW |
654 | /* Wait for the operation carried out in parallel with us. */ |
655 | for (;;) { | |
656 | prepare_to_wait(&dev->power.wait_queue, &wait, | |
657 | TASK_UNINTERRUPTIBLE); | |
658 | if (dev->power.runtime_status != RPM_RESUMING | |
659 | && dev->power.runtime_status != RPM_SUSPENDING) | |
660 | break; | |
661 | ||
662 | spin_unlock_irq(&dev->power.lock); | |
663 | ||
664 | schedule(); | |
665 | ||
666 | spin_lock_irq(&dev->power.lock); | |
667 | } | |
668 | finish_wait(&dev->power.wait_queue, &wait); | |
669 | goto repeat; | |
670 | } | |
671 | ||
7490e442 AS |
672 | /* |
673 | * See if we can skip waking up the parent. This is safe only if | |
674 | * power.no_callbacks is set, because otherwise we don't know whether | |
675 | * the resume will actually succeed. | |
676 | */ | |
677 | if (dev->power.no_callbacks && !parent && dev->parent) { | |
d63be5f9 | 678 | spin_lock_nested(&dev->parent->power.lock, SINGLE_DEPTH_NESTING); |
7490e442 AS |
679 | if (dev->parent->power.disable_depth > 0 |
680 | || dev->parent->power.ignore_children | |
681 | || dev->parent->power.runtime_status == RPM_ACTIVE) { | |
682 | atomic_inc(&dev->parent->power.child_count); | |
683 | spin_unlock(&dev->parent->power.lock); | |
7f321c26 | 684 | retval = 1; |
7490e442 AS |
685 | goto no_callback; /* Assume success. */ |
686 | } | |
687 | spin_unlock(&dev->parent->power.lock); | |
688 | } | |
689 | ||
1bfee5bc AS |
690 | /* Carry out an asynchronous or a synchronous resume. */ |
691 | if (rpmflags & RPM_ASYNC) { | |
692 | dev->power.request = RPM_REQ_RESUME; | |
693 | if (!dev->power.request_pending) { | |
694 | dev->power.request_pending = true; | |
695 | queue_work(pm_wq, &dev->power.work); | |
696 | } | |
697 | retval = 0; | |
698 | goto out; | |
699 | } | |
700 | ||
5e928f77 RW |
701 | if (!parent && dev->parent) { |
702 | /* | |
c7b61de5 AS |
703 | * Increment the parent's usage counter and resume it if |
704 | * necessary. Not needed if dev is irq-safe; then the | |
705 | * parent is permanently resumed. | |
5e928f77 RW |
706 | */ |
707 | parent = dev->parent; | |
c7b61de5 AS |
708 | if (dev->power.irq_safe) |
709 | goto skip_parent; | |
862f89b3 | 710 | spin_unlock(&dev->power.lock); |
5e928f77 RW |
711 | |
712 | pm_runtime_get_noresume(parent); | |
713 | ||
862f89b3 | 714 | spin_lock(&parent->power.lock); |
5e928f77 | 715 | /* |
216ef0b6 UH |
716 | * Resume the parent if it has runtime PM enabled and not been |
717 | * set to ignore its children. | |
5e928f77 RW |
718 | */ |
719 | if (!parent->power.disable_depth | |
720 | && !parent->power.ignore_children) { | |
140a6c94 | 721 | rpm_resume(parent, 0); |
5e928f77 RW |
722 | if (parent->power.runtime_status != RPM_ACTIVE) |
723 | retval = -EBUSY; | |
724 | } | |
862f89b3 | 725 | spin_unlock(&parent->power.lock); |
5e928f77 | 726 | |
862f89b3 | 727 | spin_lock(&dev->power.lock); |
5e928f77 RW |
728 | if (retval) |
729 | goto out; | |
730 | goto repeat; | |
731 | } | |
c7b61de5 | 732 | skip_parent: |
5e928f77 | 733 | |
7490e442 AS |
734 | if (dev->power.no_callbacks) |
735 | goto no_callback; /* Assume success. */ | |
736 | ||
8d4b9d1b | 737 | __update_runtime_status(dev, RPM_RESUMING); |
5e928f77 | 738 | |
dbcd2d72 | 739 | callback = RPM_GET_CALLBACK(dev, runtime_resume); |
35cd133c | 740 | |
4990d4fe | 741 | dev_pm_disable_wake_irq(dev); |
71c63122 | 742 | retval = rpm_callback(callback, dev); |
5e928f77 | 743 | if (retval) { |
8d4b9d1b | 744 | __update_runtime_status(dev, RPM_SUSPENDED); |
5e928f77 | 745 | pm_runtime_cancel_pending(dev); |
4990d4fe | 746 | dev_pm_enable_wake_irq(dev); |
5e928f77 | 747 | } else { |
7490e442 | 748 | no_callback: |
8d4b9d1b | 749 | __update_runtime_status(dev, RPM_ACTIVE); |
56f487c7 | 750 | pm_runtime_mark_last_busy(dev); |
5e928f77 RW |
751 | if (parent) |
752 | atomic_inc(&parent->power.child_count); | |
753 | } | |
754 | wake_up_all(&dev->power.wait_queue); | |
755 | ||
7f321c26 | 756 | if (retval >= 0) |
140a6c94 | 757 | rpm_idle(dev, RPM_ASYNC); |
5e928f77 RW |
758 | |
759 | out: | |
c7b61de5 | 760 | if (parent && !dev->power.irq_safe) { |
5e928f77 RW |
761 | spin_unlock_irq(&dev->power.lock); |
762 | ||
763 | pm_runtime_put(parent); | |
764 | ||
765 | spin_lock_irq(&dev->power.lock); | |
766 | } | |
767 | ||
d44c950e | 768 | trace_rpm_return_int_rcuidle(dev, _THIS_IP_, retval); |
5e928f77 RW |
769 | |
770 | return retval; | |
771 | } | |
772 | ||
5e928f77 | 773 | /** |
62052ab1 | 774 | * pm_runtime_work - Universal runtime PM work function. |
5e928f77 RW |
775 | * @work: Work structure used for scheduling the execution of this function. |
776 | * | |
777 | * Use @work to get the device object the work is to be done for, determine what | |
62052ab1 | 778 | * is to be done and execute the appropriate runtime PM function. |
5e928f77 RW |
779 | */ |
780 | static void pm_runtime_work(struct work_struct *work) | |
781 | { | |
782 | struct device *dev = container_of(work, struct device, power.work); | |
783 | enum rpm_request req; | |
784 | ||
785 | spin_lock_irq(&dev->power.lock); | |
786 | ||
787 | if (!dev->power.request_pending) | |
788 | goto out; | |
789 | ||
790 | req = dev->power.request; | |
791 | dev->power.request = RPM_REQ_NONE; | |
792 | dev->power.request_pending = false; | |
793 | ||
794 | switch (req) { | |
795 | case RPM_REQ_NONE: | |
796 | break; | |
797 | case RPM_REQ_IDLE: | |
140a6c94 | 798 | rpm_idle(dev, RPM_NOWAIT); |
5e928f77 RW |
799 | break; |
800 | case RPM_REQ_SUSPEND: | |
140a6c94 | 801 | rpm_suspend(dev, RPM_NOWAIT); |
5e928f77 | 802 | break; |
15bcb91d AS |
803 | case RPM_REQ_AUTOSUSPEND: |
804 | rpm_suspend(dev, RPM_NOWAIT | RPM_AUTO); | |
805 | break; | |
5e928f77 | 806 | case RPM_REQ_RESUME: |
140a6c94 | 807 | rpm_resume(dev, RPM_NOWAIT); |
5e928f77 RW |
808 | break; |
809 | } | |
810 | ||
811 | out: | |
812 | spin_unlock_irq(&dev->power.lock); | |
813 | } | |
814 | ||
5e928f77 RW |
815 | /** |
816 | * pm_suspend_timer_fn - Timer function for pm_schedule_suspend(). | |
817 | * @data: Device pointer passed by pm_schedule_suspend(). | |
818 | * | |
1bfee5bc | 819 | * Check if the time is right and queue a suspend request. |
5e928f77 RW |
820 | */ |
821 | static void pm_suspend_timer_fn(unsigned long data) | |
822 | { | |
823 | struct device *dev = (struct device *)data; | |
824 | unsigned long flags; | |
825 | unsigned long expires; | |
826 | ||
827 | spin_lock_irqsave(&dev->power.lock, flags); | |
828 | ||
829 | expires = dev->power.timer_expires; | |
830 | /* If 'expire' is after 'jiffies' we've been called too early. */ | |
831 | if (expires > 0 && !time_after(expires, jiffies)) { | |
832 | dev->power.timer_expires = 0; | |
15bcb91d AS |
833 | rpm_suspend(dev, dev->power.timer_autosuspends ? |
834 | (RPM_ASYNC | RPM_AUTO) : RPM_ASYNC); | |
5e928f77 RW |
835 | } |
836 | ||
837 | spin_unlock_irqrestore(&dev->power.lock, flags); | |
838 | } | |
839 | ||
840 | /** | |
841 | * pm_schedule_suspend - Set up a timer to submit a suspend request in future. | |
842 | * @dev: Device to suspend. | |
843 | * @delay: Time to wait before submitting a suspend request, in milliseconds. | |
844 | */ | |
845 | int pm_schedule_suspend(struct device *dev, unsigned int delay) | |
846 | { | |
847 | unsigned long flags; | |
1bfee5bc | 848 | int retval; |
5e928f77 RW |
849 | |
850 | spin_lock_irqsave(&dev->power.lock, flags); | |
851 | ||
5e928f77 | 852 | if (!delay) { |
140a6c94 | 853 | retval = rpm_suspend(dev, RPM_ASYNC); |
5e928f77 RW |
854 | goto out; |
855 | } | |
856 | ||
1bfee5bc | 857 | retval = rpm_check_suspend_allowed(dev); |
5e928f77 RW |
858 | if (retval) |
859 | goto out; | |
860 | ||
1bfee5bc AS |
861 | /* Other scheduled or pending requests need to be canceled. */ |
862 | pm_runtime_cancel_pending(dev); | |
863 | ||
5e928f77 | 864 | dev->power.timer_expires = jiffies + msecs_to_jiffies(delay); |
1bfee5bc | 865 | dev->power.timer_expires += !dev->power.timer_expires; |
15bcb91d | 866 | dev->power.timer_autosuspends = 0; |
5e928f77 RW |
867 | mod_timer(&dev->power.suspend_timer, dev->power.timer_expires); |
868 | ||
869 | out: | |
870 | spin_unlock_irqrestore(&dev->power.lock, flags); | |
871 | ||
872 | return retval; | |
873 | } | |
874 | EXPORT_SYMBOL_GPL(pm_schedule_suspend); | |
875 | ||
5e928f77 | 876 | /** |
62052ab1 | 877 | * __pm_runtime_idle - Entry point for runtime idle operations. |
140a6c94 AS |
878 | * @dev: Device to send idle notification for. |
879 | * @rpmflags: Flag bits. | |
880 | * | |
881 | * If the RPM_GET_PUT flag is set, decrement the device's usage count and | |
882 | * return immediately if it is larger than zero. Then carry out an idle | |
883 | * notification, either synchronous or asynchronous. | |
884 | * | |
311aab73 CC |
885 | * This routine may be called in atomic context if the RPM_ASYNC flag is set, |
886 | * or if pm_runtime_irq_safe() has been called. | |
5e928f77 | 887 | */ |
140a6c94 | 888 | int __pm_runtime_idle(struct device *dev, int rpmflags) |
5e928f77 RW |
889 | { |
890 | unsigned long flags; | |
891 | int retval; | |
892 | ||
311aab73 CC |
893 | might_sleep_if(!(rpmflags & RPM_ASYNC) && !dev->power.irq_safe); |
894 | ||
140a6c94 AS |
895 | if (rpmflags & RPM_GET_PUT) { |
896 | if (!atomic_dec_and_test(&dev->power.usage_count)) | |
897 | return 0; | |
898 | } | |
899 | ||
5e928f77 | 900 | spin_lock_irqsave(&dev->power.lock, flags); |
140a6c94 | 901 | retval = rpm_idle(dev, rpmflags); |
5e928f77 RW |
902 | spin_unlock_irqrestore(&dev->power.lock, flags); |
903 | ||
904 | return retval; | |
905 | } | |
140a6c94 | 906 | EXPORT_SYMBOL_GPL(__pm_runtime_idle); |
5e928f77 RW |
907 | |
908 | /** | |
62052ab1 | 909 | * __pm_runtime_suspend - Entry point for runtime put/suspend operations. |
140a6c94 | 910 | * @dev: Device to suspend. |
3f9af051 | 911 | * @rpmflags: Flag bits. |
5e928f77 | 912 | * |
15bcb91d AS |
913 | * If the RPM_GET_PUT flag is set, decrement the device's usage count and |
914 | * return immediately if it is larger than zero. Then carry out a suspend, | |
915 | * either synchronous or asynchronous. | |
140a6c94 | 916 | * |
311aab73 CC |
917 | * This routine may be called in atomic context if the RPM_ASYNC flag is set, |
918 | * or if pm_runtime_irq_safe() has been called. | |
5e928f77 | 919 | */ |
140a6c94 | 920 | int __pm_runtime_suspend(struct device *dev, int rpmflags) |
5e928f77 | 921 | { |
140a6c94 | 922 | unsigned long flags; |
1d531c14 | 923 | int retval; |
5e928f77 | 924 | |
311aab73 CC |
925 | might_sleep_if(!(rpmflags & RPM_ASYNC) && !dev->power.irq_safe); |
926 | ||
15bcb91d AS |
927 | if (rpmflags & RPM_GET_PUT) { |
928 | if (!atomic_dec_and_test(&dev->power.usage_count)) | |
929 | return 0; | |
930 | } | |
931 | ||
140a6c94 AS |
932 | spin_lock_irqsave(&dev->power.lock, flags); |
933 | retval = rpm_suspend(dev, rpmflags); | |
934 | spin_unlock_irqrestore(&dev->power.lock, flags); | |
5e928f77 RW |
935 | |
936 | return retval; | |
937 | } | |
140a6c94 | 938 | EXPORT_SYMBOL_GPL(__pm_runtime_suspend); |
5e928f77 RW |
939 | |
940 | /** | |
62052ab1 | 941 | * __pm_runtime_resume - Entry point for runtime resume operations. |
140a6c94 | 942 | * @dev: Device to resume. |
3f9af051 | 943 | * @rpmflags: Flag bits. |
5e928f77 | 944 | * |
140a6c94 AS |
945 | * If the RPM_GET_PUT flag is set, increment the device's usage count. Then |
946 | * carry out a resume, either synchronous or asynchronous. | |
947 | * | |
311aab73 CC |
948 | * This routine may be called in atomic context if the RPM_ASYNC flag is set, |
949 | * or if pm_runtime_irq_safe() has been called. | |
5e928f77 | 950 | */ |
140a6c94 | 951 | int __pm_runtime_resume(struct device *dev, int rpmflags) |
5e928f77 | 952 | { |
140a6c94 AS |
953 | unsigned long flags; |
954 | int retval; | |
5e928f77 | 955 | |
311aab73 CC |
956 | might_sleep_if(!(rpmflags & RPM_ASYNC) && !dev->power.irq_safe); |
957 | ||
140a6c94 AS |
958 | if (rpmflags & RPM_GET_PUT) |
959 | atomic_inc(&dev->power.usage_count); | |
960 | ||
961 | spin_lock_irqsave(&dev->power.lock, flags); | |
962 | retval = rpm_resume(dev, rpmflags); | |
963 | spin_unlock_irqrestore(&dev->power.lock, flags); | |
5e928f77 RW |
964 | |
965 | return retval; | |
966 | } | |
140a6c94 | 967 | EXPORT_SYMBOL_GPL(__pm_runtime_resume); |
5e928f77 | 968 | |
a436b6a1 RW |
969 | /** |
970 | * pm_runtime_get_if_in_use - Conditionally bump up the device's usage counter. | |
971 | * @dev: Device to handle. | |
972 | * | |
973 | * Return -EINVAL if runtime PM is disabled for the device. | |
974 | * | |
975 | * If that's not the case and if the device's runtime PM status is RPM_ACTIVE | |
976 | * and the runtime PM usage counter is nonzero, increment the counter and | |
977 | * return 1. Otherwise return 0 without changing the counter. | |
978 | */ | |
979 | int pm_runtime_get_if_in_use(struct device *dev) | |
980 | { | |
981 | unsigned long flags; | |
982 | int retval; | |
983 | ||
984 | spin_lock_irqsave(&dev->power.lock, flags); | |
985 | retval = dev->power.disable_depth > 0 ? -EINVAL : | |
986 | dev->power.runtime_status == RPM_ACTIVE | |
987 | && atomic_inc_not_zero(&dev->power.usage_count); | |
988 | spin_unlock_irqrestore(&dev->power.lock, flags); | |
989 | return retval; | |
990 | } | |
991 | EXPORT_SYMBOL_GPL(pm_runtime_get_if_in_use); | |
992 | ||
5e928f77 | 993 | /** |
62052ab1 | 994 | * __pm_runtime_set_status - Set runtime PM status of a device. |
5e928f77 | 995 | * @dev: Device to handle. |
62052ab1 | 996 | * @status: New runtime PM status of the device. |
5e928f77 | 997 | * |
62052ab1 | 998 | * If runtime PM of the device is disabled or its power.runtime_error field is |
5e928f77 RW |
999 | * different from zero, the status may be changed either to RPM_ACTIVE, or to |
1000 | * RPM_SUSPENDED, as long as that reflects the actual state of the device. | |
1001 | * However, if the device has a parent and the parent is not active, and the | |
1002 | * parent's power.ignore_children flag is unset, the device's status cannot be | |
1003 | * set to RPM_ACTIVE, so -EBUSY is returned in that case. | |
1004 | * | |
1005 | * If successful, __pm_runtime_set_status() clears the power.runtime_error field | |
1006 | * and the device parent's counter of unsuspended children is modified to | |
1007 | * reflect the new status. If the new status is RPM_SUSPENDED, an idle | |
1008 | * notification request for the parent is submitted. | |
1009 | */ | |
1010 | int __pm_runtime_set_status(struct device *dev, unsigned int status) | |
1011 | { | |
1012 | struct device *parent = dev->parent; | |
1013 | unsigned long flags; | |
1014 | bool notify_parent = false; | |
1015 | int error = 0; | |
1016 | ||
1017 | if (status != RPM_ACTIVE && status != RPM_SUSPENDED) | |
1018 | return -EINVAL; | |
1019 | ||
1020 | spin_lock_irqsave(&dev->power.lock, flags); | |
1021 | ||
1022 | if (!dev->power.runtime_error && !dev->power.disable_depth) { | |
1023 | error = -EAGAIN; | |
1024 | goto out; | |
1025 | } | |
1026 | ||
1027 | if (dev->power.runtime_status == status) | |
1028 | goto out_set; | |
1029 | ||
1030 | if (status == RPM_SUSPENDED) { | |
a8636c89 UH |
1031 | /* |
1032 | * It is invalid to suspend a device with an active child, | |
1033 | * unless it has been set to ignore its children. | |
1034 | */ | |
1035 | if (!dev->power.ignore_children && | |
1036 | atomic_read(&dev->power.child_count)) { | |
1037 | dev_err(dev, "runtime PM trying to suspend device but active child\n"); | |
1038 | error = -EBUSY; | |
1039 | goto out; | |
1040 | } | |
1041 | ||
5e928f77 RW |
1042 | if (parent) { |
1043 | atomic_add_unless(&parent->power.child_count, -1, 0); | |
1044 | notify_parent = !parent->power.ignore_children; | |
1045 | } | |
1046 | goto out_set; | |
1047 | } | |
1048 | ||
1049 | if (parent) { | |
bab636b9 | 1050 | spin_lock_nested(&parent->power.lock, SINGLE_DEPTH_NESTING); |
5e928f77 RW |
1051 | |
1052 | /* | |
1053 | * It is invalid to put an active child under a parent that is | |
62052ab1 | 1054 | * not active, has runtime PM enabled and the |
5e928f77 RW |
1055 | * 'power.ignore_children' flag unset. |
1056 | */ | |
1057 | if (!parent->power.disable_depth | |
1058 | && !parent->power.ignore_children | |
71723f95 LW |
1059 | && parent->power.runtime_status != RPM_ACTIVE) { |
1060 | dev_err(dev, "runtime PM trying to activate child device %s but parent (%s) is not active\n", | |
1061 | dev_name(dev), | |
1062 | dev_name(parent)); | |
5e928f77 | 1063 | error = -EBUSY; |
71723f95 | 1064 | } else if (dev->power.runtime_status == RPM_SUSPENDED) { |
965c4ac0 | 1065 | atomic_inc(&parent->power.child_count); |
71723f95 | 1066 | } |
5e928f77 | 1067 | |
862f89b3 | 1068 | spin_unlock(&parent->power.lock); |
5e928f77 RW |
1069 | |
1070 | if (error) | |
1071 | goto out; | |
1072 | } | |
1073 | ||
1074 | out_set: | |
8d4b9d1b | 1075 | __update_runtime_status(dev, status); |
5e928f77 RW |
1076 | dev->power.runtime_error = 0; |
1077 | out: | |
1078 | spin_unlock_irqrestore(&dev->power.lock, flags); | |
1079 | ||
1080 | if (notify_parent) | |
1081 | pm_request_idle(parent); | |
1082 | ||
1083 | return error; | |
1084 | } | |
1085 | EXPORT_SYMBOL_GPL(__pm_runtime_set_status); | |
1086 | ||
1087 | /** | |
1088 | * __pm_runtime_barrier - Cancel pending requests and wait for completions. | |
1089 | * @dev: Device to handle. | |
1090 | * | |
1091 | * Flush all pending requests for the device from pm_wq and wait for all | |
62052ab1 | 1092 | * runtime PM operations involving the device in progress to complete. |
5e928f77 RW |
1093 | * |
1094 | * Should be called under dev->power.lock with interrupts disabled. | |
1095 | */ | |
1096 | static void __pm_runtime_barrier(struct device *dev) | |
1097 | { | |
1098 | pm_runtime_deactivate_timer(dev); | |
1099 | ||
1100 | if (dev->power.request_pending) { | |
1101 | dev->power.request = RPM_REQ_NONE; | |
1102 | spin_unlock_irq(&dev->power.lock); | |
1103 | ||
1104 | cancel_work_sync(&dev->power.work); | |
1105 | ||
1106 | spin_lock_irq(&dev->power.lock); | |
1107 | dev->power.request_pending = false; | |
1108 | } | |
1109 | ||
1110 | if (dev->power.runtime_status == RPM_SUSPENDING | |
1111 | || dev->power.runtime_status == RPM_RESUMING | |
1112 | || dev->power.idle_notification) { | |
1113 | DEFINE_WAIT(wait); | |
1114 | ||
1115 | /* Suspend, wake-up or idle notification in progress. */ | |
1116 | for (;;) { | |
1117 | prepare_to_wait(&dev->power.wait_queue, &wait, | |
1118 | TASK_UNINTERRUPTIBLE); | |
1119 | if (dev->power.runtime_status != RPM_SUSPENDING | |
1120 | && dev->power.runtime_status != RPM_RESUMING | |
1121 | && !dev->power.idle_notification) | |
1122 | break; | |
1123 | spin_unlock_irq(&dev->power.lock); | |
1124 | ||
1125 | schedule(); | |
1126 | ||
1127 | spin_lock_irq(&dev->power.lock); | |
1128 | } | |
1129 | finish_wait(&dev->power.wait_queue, &wait); | |
1130 | } | |
1131 | } | |
1132 | ||
1133 | /** | |
1134 | * pm_runtime_barrier - Flush pending requests and wait for completions. | |
1135 | * @dev: Device to handle. | |
1136 | * | |
1137 | * Prevent the device from being suspended by incrementing its usage counter and | |
1138 | * if there's a pending resume request for the device, wake the device up. | |
1139 | * Next, make sure that all pending requests for the device have been flushed | |
62052ab1 | 1140 | * from pm_wq and wait for all runtime PM operations involving the device in |
5e928f77 RW |
1141 | * progress to complete. |
1142 | * | |
1143 | * Return value: | |
1144 | * 1, if there was a resume request pending and the device had to be woken up, | |
1145 | * 0, otherwise | |
1146 | */ | |
1147 | int pm_runtime_barrier(struct device *dev) | |
1148 | { | |
1149 | int retval = 0; | |
1150 | ||
1151 | pm_runtime_get_noresume(dev); | |
1152 | spin_lock_irq(&dev->power.lock); | |
1153 | ||
1154 | if (dev->power.request_pending | |
1155 | && dev->power.request == RPM_REQ_RESUME) { | |
140a6c94 | 1156 | rpm_resume(dev, 0); |
5e928f77 RW |
1157 | retval = 1; |
1158 | } | |
1159 | ||
1160 | __pm_runtime_barrier(dev); | |
1161 | ||
1162 | spin_unlock_irq(&dev->power.lock); | |
1163 | pm_runtime_put_noidle(dev); | |
1164 | ||
1165 | return retval; | |
1166 | } | |
1167 | EXPORT_SYMBOL_GPL(pm_runtime_barrier); | |
1168 | ||
1169 | /** | |
62052ab1 | 1170 | * __pm_runtime_disable - Disable runtime PM of a device. |
5e928f77 RW |
1171 | * @dev: Device to handle. |
1172 | * @check_resume: If set, check if there's a resume request for the device. | |
1173 | * | |
7b60894f | 1174 | * Increment power.disable_depth for the device and if it was zero previously, |
62052ab1 | 1175 | * cancel all pending runtime PM requests for the device and wait for all |
5e928f77 | 1176 | * operations in progress to complete. The device can be either active or |
62052ab1 | 1177 | * suspended after its runtime PM has been disabled. |
5e928f77 RW |
1178 | * |
1179 | * If @check_resume is set and there's a resume request pending when | |
1180 | * __pm_runtime_disable() is called and power.disable_depth is zero, the | |
62052ab1 | 1181 | * function will wake up the device before disabling its runtime PM. |
5e928f77 RW |
1182 | */ |
1183 | void __pm_runtime_disable(struct device *dev, bool check_resume) | |
1184 | { | |
1185 | spin_lock_irq(&dev->power.lock); | |
1186 | ||
1187 | if (dev->power.disable_depth > 0) { | |
1188 | dev->power.disable_depth++; | |
1189 | goto out; | |
1190 | } | |
1191 | ||
1192 | /* | |
1193 | * Wake up the device if there's a resume request pending, because that | |
62052ab1 | 1194 | * means there probably is some I/O to process and disabling runtime PM |
5e928f77 RW |
1195 | * shouldn't prevent the device from processing the I/O. |
1196 | */ | |
1197 | if (check_resume && dev->power.request_pending | |
1198 | && dev->power.request == RPM_REQ_RESUME) { | |
1199 | /* | |
1200 | * Prevent suspends and idle notifications from being carried | |
1201 | * out after we have woken up the device. | |
1202 | */ | |
1203 | pm_runtime_get_noresume(dev); | |
1204 | ||
140a6c94 | 1205 | rpm_resume(dev, 0); |
5e928f77 RW |
1206 | |
1207 | pm_runtime_put_noidle(dev); | |
1208 | } | |
1209 | ||
1210 | if (!dev->power.disable_depth++) | |
1211 | __pm_runtime_barrier(dev); | |
1212 | ||
1213 | out: | |
1214 | spin_unlock_irq(&dev->power.lock); | |
1215 | } | |
1216 | EXPORT_SYMBOL_GPL(__pm_runtime_disable); | |
1217 | ||
1218 | /** | |
62052ab1 | 1219 | * pm_runtime_enable - Enable runtime PM of a device. |
5e928f77 RW |
1220 | * @dev: Device to handle. |
1221 | */ | |
1222 | void pm_runtime_enable(struct device *dev) | |
1223 | { | |
1224 | unsigned long flags; | |
1225 | ||
1226 | spin_lock_irqsave(&dev->power.lock, flags); | |
1227 | ||
1228 | if (dev->power.disable_depth > 0) | |
1229 | dev->power.disable_depth--; | |
1230 | else | |
1231 | dev_warn(dev, "Unbalanced %s!\n", __func__); | |
1232 | ||
1233 | spin_unlock_irqrestore(&dev->power.lock, flags); | |
1234 | } | |
1235 | EXPORT_SYMBOL_GPL(pm_runtime_enable); | |
1236 | ||
53823639 | 1237 | /** |
62052ab1 | 1238 | * pm_runtime_forbid - Block runtime PM of a device. |
53823639 RW |
1239 | * @dev: Device to handle. |
1240 | * | |
1241 | * Increase the device's usage count and clear its power.runtime_auto flag, | |
1242 | * so that it cannot be suspended at run time until pm_runtime_allow() is called | |
1243 | * for it. | |
1244 | */ | |
1245 | void pm_runtime_forbid(struct device *dev) | |
1246 | { | |
1247 | spin_lock_irq(&dev->power.lock); | |
1248 | if (!dev->power.runtime_auto) | |
1249 | goto out; | |
1250 | ||
1251 | dev->power.runtime_auto = false; | |
1252 | atomic_inc(&dev->power.usage_count); | |
140a6c94 | 1253 | rpm_resume(dev, 0); |
53823639 RW |
1254 | |
1255 | out: | |
1256 | spin_unlock_irq(&dev->power.lock); | |
1257 | } | |
1258 | EXPORT_SYMBOL_GPL(pm_runtime_forbid); | |
1259 | ||
1260 | /** | |
62052ab1 | 1261 | * pm_runtime_allow - Unblock runtime PM of a device. |
53823639 RW |
1262 | * @dev: Device to handle. |
1263 | * | |
1264 | * Decrease the device's usage count and set its power.runtime_auto flag. | |
1265 | */ | |
1266 | void pm_runtime_allow(struct device *dev) | |
1267 | { | |
1268 | spin_lock_irq(&dev->power.lock); | |
1269 | if (dev->power.runtime_auto) | |
1270 | goto out; | |
1271 | ||
1272 | dev->power.runtime_auto = true; | |
1273 | if (atomic_dec_and_test(&dev->power.usage_count)) | |
fe7450b0 | 1274 | rpm_idle(dev, RPM_AUTO | RPM_ASYNC); |
53823639 RW |
1275 | |
1276 | out: | |
1277 | spin_unlock_irq(&dev->power.lock); | |
1278 | } | |
1279 | EXPORT_SYMBOL_GPL(pm_runtime_allow); | |
1280 | ||
7490e442 | 1281 | /** |
62052ab1 | 1282 | * pm_runtime_no_callbacks - Ignore runtime PM callbacks for a device. |
7490e442 AS |
1283 | * @dev: Device to handle. |
1284 | * | |
1285 | * Set the power.no_callbacks flag, which tells the PM core that this | |
62052ab1 RW |
1286 | * device is power-managed through its parent and has no runtime PM |
1287 | * callbacks of its own. The runtime sysfs attributes will be removed. | |
7490e442 AS |
1288 | */ |
1289 | void pm_runtime_no_callbacks(struct device *dev) | |
1290 | { | |
1291 | spin_lock_irq(&dev->power.lock); | |
1292 | dev->power.no_callbacks = 1; | |
1293 | spin_unlock_irq(&dev->power.lock); | |
1294 | if (device_is_registered(dev)) | |
1295 | rpm_sysfs_remove(dev); | |
1296 | } | |
1297 | EXPORT_SYMBOL_GPL(pm_runtime_no_callbacks); | |
1298 | ||
c7b61de5 AS |
1299 | /** |
1300 | * pm_runtime_irq_safe - Leave interrupts disabled during callbacks. | |
1301 | * @dev: Device to handle | |
1302 | * | |
1303 | * Set the power.irq_safe flag, which tells the PM core that the | |
1304 | * ->runtime_suspend() and ->runtime_resume() callbacks for this device should | |
1305 | * always be invoked with the spinlock held and interrupts disabled. It also | |
1306 | * causes the parent's usage counter to be permanently incremented, preventing | |
1307 | * the parent from runtime suspending -- otherwise an irq-safe child might have | |
1308 | * to wait for a non-irq-safe parent. | |
1309 | */ | |
1310 | void pm_runtime_irq_safe(struct device *dev) | |
1311 | { | |
1312 | if (dev->parent) | |
1313 | pm_runtime_get_sync(dev->parent); | |
1314 | spin_lock_irq(&dev->power.lock); | |
1315 | dev->power.irq_safe = 1; | |
1316 | spin_unlock_irq(&dev->power.lock); | |
1317 | } | |
1318 | EXPORT_SYMBOL_GPL(pm_runtime_irq_safe); | |
1319 | ||
15bcb91d AS |
1320 | /** |
1321 | * update_autosuspend - Handle a change to a device's autosuspend settings. | |
1322 | * @dev: Device to handle. | |
1323 | * @old_delay: The former autosuspend_delay value. | |
1324 | * @old_use: The former use_autosuspend value. | |
1325 | * | |
1326 | * Prevent runtime suspend if the new delay is negative and use_autosuspend is | |
1327 | * set; otherwise allow it. Send an idle notification if suspends are allowed. | |
1328 | * | |
1329 | * This function must be called under dev->power.lock with interrupts disabled. | |
1330 | */ | |
1331 | static void update_autosuspend(struct device *dev, int old_delay, int old_use) | |
1332 | { | |
1333 | int delay = dev->power.autosuspend_delay; | |
1334 | ||
1335 | /* Should runtime suspend be prevented now? */ | |
1336 | if (dev->power.use_autosuspend && delay < 0) { | |
1337 | ||
1338 | /* If it used to be allowed then prevent it. */ | |
1339 | if (!old_use || old_delay >= 0) { | |
1340 | atomic_inc(&dev->power.usage_count); | |
1341 | rpm_resume(dev, 0); | |
1342 | } | |
1343 | } | |
1344 | ||
1345 | /* Runtime suspend should be allowed now. */ | |
1346 | else { | |
1347 | ||
1348 | /* If it used to be prevented then allow it. */ | |
1349 | if (old_use && old_delay < 0) | |
1350 | atomic_dec(&dev->power.usage_count); | |
1351 | ||
1352 | /* Maybe we can autosuspend now. */ | |
1353 | rpm_idle(dev, RPM_AUTO); | |
1354 | } | |
1355 | } | |
1356 | ||
1357 | /** | |
1358 | * pm_runtime_set_autosuspend_delay - Set a device's autosuspend_delay value. | |
1359 | * @dev: Device to handle. | |
1360 | * @delay: Value of the new delay in milliseconds. | |
1361 | * | |
1362 | * Set the device's power.autosuspend_delay value. If it changes to negative | |
62052ab1 RW |
1363 | * and the power.use_autosuspend flag is set, prevent runtime suspends. If it |
1364 | * changes the other way, allow runtime suspends. | |
15bcb91d AS |
1365 | */ |
1366 | void pm_runtime_set_autosuspend_delay(struct device *dev, int delay) | |
1367 | { | |
1368 | int old_delay, old_use; | |
1369 | ||
1370 | spin_lock_irq(&dev->power.lock); | |
1371 | old_delay = dev->power.autosuspend_delay; | |
1372 | old_use = dev->power.use_autosuspend; | |
1373 | dev->power.autosuspend_delay = delay; | |
1374 | update_autosuspend(dev, old_delay, old_use); | |
1375 | spin_unlock_irq(&dev->power.lock); | |
1376 | } | |
1377 | EXPORT_SYMBOL_GPL(pm_runtime_set_autosuspend_delay); | |
1378 | ||
1379 | /** | |
1380 | * __pm_runtime_use_autosuspend - Set a device's use_autosuspend flag. | |
1381 | * @dev: Device to handle. | |
1382 | * @use: New value for use_autosuspend. | |
1383 | * | |
62052ab1 | 1384 | * Set the device's power.use_autosuspend flag, and allow or prevent runtime |
15bcb91d AS |
1385 | * suspends as needed. |
1386 | */ | |
1387 | void __pm_runtime_use_autosuspend(struct device *dev, bool use) | |
1388 | { | |
1389 | int old_delay, old_use; | |
1390 | ||
1391 | spin_lock_irq(&dev->power.lock); | |
1392 | old_delay = dev->power.autosuspend_delay; | |
1393 | old_use = dev->power.use_autosuspend; | |
1394 | dev->power.use_autosuspend = use; | |
1395 | update_autosuspend(dev, old_delay, old_use); | |
1396 | spin_unlock_irq(&dev->power.lock); | |
1397 | } | |
1398 | EXPORT_SYMBOL_GPL(__pm_runtime_use_autosuspend); | |
1399 | ||
5e928f77 | 1400 | /** |
62052ab1 | 1401 | * pm_runtime_init - Initialize runtime PM fields in given device object. |
5e928f77 RW |
1402 | * @dev: Device object to initialize. |
1403 | */ | |
1404 | void pm_runtime_init(struct device *dev) | |
1405 | { | |
5e928f77 RW |
1406 | dev->power.runtime_status = RPM_SUSPENDED; |
1407 | dev->power.idle_notification = false; | |
1408 | ||
1409 | dev->power.disable_depth = 1; | |
1410 | atomic_set(&dev->power.usage_count, 0); | |
1411 | ||
1412 | dev->power.runtime_error = 0; | |
1413 | ||
1414 | atomic_set(&dev->power.child_count, 0); | |
1415 | pm_suspend_ignore_children(dev, false); | |
53823639 | 1416 | dev->power.runtime_auto = true; |
5e928f77 RW |
1417 | |
1418 | dev->power.request_pending = false; | |
1419 | dev->power.request = RPM_REQ_NONE; | |
1420 | dev->power.deferred_resume = false; | |
8d4b9d1b | 1421 | dev->power.accounting_timestamp = jiffies; |
5e928f77 RW |
1422 | INIT_WORK(&dev->power.work, pm_runtime_work); |
1423 | ||
1424 | dev->power.timer_expires = 0; | |
1425 | setup_timer(&dev->power.suspend_timer, pm_suspend_timer_fn, | |
1426 | (unsigned long)dev); | |
1427 | ||
1428 | init_waitqueue_head(&dev->power.wait_queue); | |
1429 | } | |
1430 | ||
5de85b9d UH |
1431 | /** |
1432 | * pm_runtime_reinit - Re-initialize runtime PM fields in given device object. | |
1433 | * @dev: Device object to re-initialize. | |
1434 | */ | |
1435 | void pm_runtime_reinit(struct device *dev) | |
1436 | { | |
1437 | if (!pm_runtime_enabled(dev)) { | |
1438 | if (dev->power.runtime_status == RPM_ACTIVE) | |
1439 | pm_runtime_set_suspended(dev); | |
1440 | if (dev->power.irq_safe) { | |
1441 | spin_lock_irq(&dev->power.lock); | |
1442 | dev->power.irq_safe = 0; | |
1443 | spin_unlock_irq(&dev->power.lock); | |
1444 | if (dev->parent) | |
1445 | pm_runtime_put(dev->parent); | |
1446 | } | |
1447 | } | |
1448 | } | |
1449 | ||
5e928f77 RW |
1450 | /** |
1451 | * pm_runtime_remove - Prepare for removing a device from device hierarchy. | |
1452 | * @dev: Device object being removed from device hierarchy. | |
1453 | */ | |
1454 | void pm_runtime_remove(struct device *dev) | |
1455 | { | |
1456 | __pm_runtime_disable(dev, false); | |
5de85b9d | 1457 | pm_runtime_reinit(dev); |
5e928f77 | 1458 | } |
37f20416 UH |
1459 | |
1460 | /** | |
1461 | * pm_runtime_force_suspend - Force a device into suspend state if needed. | |
1462 | * @dev: Device to suspend. | |
1463 | * | |
1464 | * Disable runtime PM so we safely can check the device's runtime PM status and | |
1465 | * if it is active, invoke it's .runtime_suspend callback to bring it into | |
1466 | * suspend state. Keep runtime PM disabled to preserve the state unless we | |
1467 | * encounter errors. | |
1468 | * | |
1469 | * Typically this function may be invoked from a system suspend callback to make | |
1470 | * sure the device is put into low power state. | |
1471 | */ | |
1472 | int pm_runtime_force_suspend(struct device *dev) | |
1473 | { | |
1474 | int (*callback)(struct device *); | |
1475 | int ret = 0; | |
1476 | ||
1477 | pm_runtime_disable(dev); | |
37f20416 UH |
1478 | if (pm_runtime_status_suspended(dev)) |
1479 | return 0; | |
1480 | ||
dbcd2d72 | 1481 | callback = RPM_GET_CALLBACK(dev, runtime_suspend); |
37f20416 UH |
1482 | |
1483 | if (!callback) { | |
1484 | ret = -ENOSYS; | |
1485 | goto err; | |
1486 | } | |
1487 | ||
1488 | ret = callback(dev); | |
1489 | if (ret) | |
1490 | goto err; | |
1491 | ||
1d9174fb UH |
1492 | /* |
1493 | * Increase the runtime PM usage count for the device's parent, in case | |
1494 | * when we find the device being used when system suspend was invoked. | |
1495 | * This informs pm_runtime_force_resume() to resume the parent | |
1496 | * immediately, which is needed to be able to resume its children, | |
1497 | * when not deferring the resume to be managed via runtime PM. | |
1498 | */ | |
1499 | if (dev->parent && atomic_read(&dev->power.usage_count) > 1) | |
1500 | pm_runtime_get_noresume(dev->parent); | |
1501 | ||
37f20416 UH |
1502 | pm_runtime_set_suspended(dev); |
1503 | return 0; | |
1504 | err: | |
1505 | pm_runtime_enable(dev); | |
1506 | return ret; | |
1507 | } | |
1508 | EXPORT_SYMBOL_GPL(pm_runtime_force_suspend); | |
1509 | ||
1510 | /** | |
1d9174fb | 1511 | * pm_runtime_force_resume - Force a device into resume state if needed. |
37f20416 UH |
1512 | * @dev: Device to resume. |
1513 | * | |
1514 | * Prior invoking this function we expect the user to have brought the device | |
1515 | * into low power state by a call to pm_runtime_force_suspend(). Here we reverse | |
1d9174fb UH |
1516 | * those actions and brings the device into full power, if it is expected to be |
1517 | * used on system resume. To distinguish that, we check whether the runtime PM | |
1518 | * usage count is greater than 1 (the PM core increases the usage count in the | |
1519 | * system PM prepare phase), as that indicates a real user (such as a subsystem, | |
1520 | * driver, userspace, etc.) is using it. If that is the case, the device is | |
1521 | * expected to be used on system resume as well, so then we resume it. In the | |
1522 | * other case, we defer the resume to be managed via runtime PM. | |
37f20416 | 1523 | * |
1d9174fb | 1524 | * Typically this function may be invoked from a system resume callback. |
37f20416 UH |
1525 | */ |
1526 | int pm_runtime_force_resume(struct device *dev) | |
1527 | { | |
1528 | int (*callback)(struct device *); | |
1529 | int ret = 0; | |
1530 | ||
dbcd2d72 | 1531 | callback = RPM_GET_CALLBACK(dev, runtime_resume); |
37f20416 UH |
1532 | |
1533 | if (!callback) { | |
1534 | ret = -ENOSYS; | |
1535 | goto out; | |
1536 | } | |
1537 | ||
9f5b5274 UH |
1538 | if (!pm_runtime_status_suspended(dev)) |
1539 | goto out; | |
1540 | ||
1d9174fb UH |
1541 | /* |
1542 | * Decrease the parent's runtime PM usage count, if we increased it | |
1543 | * during system suspend in pm_runtime_force_suspend(). | |
1544 | */ | |
1545 | if (atomic_read(&dev->power.usage_count) > 1) { | |
1546 | if (dev->parent) | |
1547 | pm_runtime_put_noidle(dev->parent); | |
1548 | } else { | |
1549 | goto out; | |
1550 | } | |
1551 | ||
0ae3aeef | 1552 | ret = pm_runtime_set_active(dev); |
37f20416 UH |
1553 | if (ret) |
1554 | goto out; | |
1555 | ||
0ae3aeef UH |
1556 | ret = callback(dev); |
1557 | if (ret) { | |
1558 | pm_runtime_set_suspended(dev); | |
1559 | goto out; | |
1560 | } | |
1561 | ||
37f20416 UH |
1562 | pm_runtime_mark_last_busy(dev); |
1563 | out: | |
1564 | pm_runtime_enable(dev); | |
1565 | return ret; | |
1566 | } | |
1567 | EXPORT_SYMBOL_GPL(pm_runtime_force_resume); |