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> |
c3dc2f14 | 13 | #include <trace/events/rpm.h> |
7490e442 | 14 | #include "power.h" |
5e928f77 | 15 | |
140a6c94 | 16 | static int rpm_resume(struct device *dev, int rpmflags); |
7490e442 | 17 | static int rpm_suspend(struct device *dev, int rpmflags); |
5e928f77 | 18 | |
4769373c AS |
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; | |
def0c0a3 | 33 | unsigned long delta; |
4769373c AS |
34 | |
35 | delta = now - dev->power.accounting_timestamp; | |
36 | ||
4769373c AS |
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 | ||
5e928f77 RW |
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 | ||
15bcb91d AS |
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 | ||
e823407f ML |
127 | static int dev_memalloc_noio(struct device *dev, void *data) |
128 | { | |
129 | return dev->power.memalloc_noio; | |
130 | } | |
131 | ||
132 | /* | |
133 | * pm_runtime_set_memalloc_noio - Set a device's memalloc_noio flag. | |
134 | * @dev: Device to handle. | |
135 | * @enable: True for setting the flag and False for clearing the flag. | |
136 | * | |
137 | * Set the flag for all devices in the path from the device to the | |
138 | * root device in the device tree if @enable is true, otherwise clear | |
139 | * the flag for devices in the path whose siblings don't set the flag. | |
140 | * | |
141 | * The function should only be called by block device, or network | |
142 | * device driver for solving the deadlock problem during runtime | |
143 | * resume/suspend: | |
144 | * | |
145 | * If memory allocation with GFP_KERNEL is called inside runtime | |
146 | * resume/suspend callback of any one of its ancestors(or the | |
147 | * block device itself), the deadlock may be triggered inside the | |
148 | * memory allocation since it might not complete until the block | |
149 | * device becomes active and the involed page I/O finishes. The | |
150 | * situation is pointed out first by Alan Stern. Network device | |
151 | * are involved in iSCSI kind of situation. | |
152 | * | |
153 | * The lock of dev_hotplug_mutex is held in the function for handling | |
154 | * hotplug race because pm_runtime_set_memalloc_noio() may be called | |
155 | * in async probe(). | |
156 | * | |
157 | * The function should be called between device_add() and device_del() | |
158 | * on the affected device(block/network device). | |
159 | */ | |
160 | void pm_runtime_set_memalloc_noio(struct device *dev, bool enable) | |
161 | { | |
162 | static DEFINE_MUTEX(dev_hotplug_mutex); | |
163 | ||
164 | mutex_lock(&dev_hotplug_mutex); | |
165 | for (;;) { | |
166 | bool enabled; | |
167 | ||
168 | /* hold power lock since bitfield is not SMP-safe. */ | |
169 | spin_lock_irq(&dev->power.lock); | |
170 | enabled = dev->power.memalloc_noio; | |
171 | dev->power.memalloc_noio = enable; | |
172 | spin_unlock_irq(&dev->power.lock); | |
173 | ||
174 | /* | |
175 | * not need to enable ancestors any more if the device | |
176 | * has been enabled. | |
177 | */ | |
178 | if (enabled && enable) | |
179 | break; | |
180 | ||
181 | dev = dev->parent; | |
182 | ||
183 | /* | |
184 | * clear flag of the parent device only if all the | |
185 | * children don't set the flag because ancestor's | |
186 | * flag was set by any one of the descendants. | |
187 | */ | |
188 | if (!dev || (!enable && | |
189 | device_for_each_child(dev, NULL, | |
190 | dev_memalloc_noio))) | |
191 | break; | |
192 | } | |
193 | mutex_unlock(&dev_hotplug_mutex); | |
194 | } | |
195 | EXPORT_SYMBOL_GPL(pm_runtime_set_memalloc_noio); | |
196 | ||
5e928f77 | 197 | /** |
1bfee5bc AS |
198 | * rpm_check_suspend_allowed - Test whether a device may be suspended. |
199 | * @dev: Device to test. | |
5e928f77 | 200 | */ |
1bfee5bc | 201 | static int rpm_check_suspend_allowed(struct device *dev) |
5e928f77 RW |
202 | { |
203 | int retval = 0; | |
204 | ||
5e928f77 RW |
205 | if (dev->power.runtime_error) |
206 | retval = -EINVAL; | |
632e270e RW |
207 | else if (dev->power.disable_depth > 0) |
208 | retval = -EACCES; | |
209 | else if (atomic_read(&dev->power.usage_count) > 0) | |
5e928f77 RW |
210 | retval = -EAGAIN; |
211 | else if (!pm_children_suspended(dev)) | |
212 | retval = -EBUSY; | |
1bfee5bc AS |
213 | |
214 | /* Pending resume requests take precedence over suspends. */ | |
215 | else if ((dev->power.deferred_resume | |
78ca7c37 | 216 | && dev->power.runtime_status == RPM_SUSPENDING) |
1bfee5bc AS |
217 | || (dev->power.request_pending |
218 | && dev->power.request == RPM_REQ_RESUME)) | |
219 | retval = -EAGAIN; | |
55d7ec45 RW |
220 | else if (__dev_pm_qos_read_value(dev) < 0) |
221 | retval = -EPERM; | |
1bfee5bc AS |
222 | else if (dev->power.runtime_status == RPM_SUSPENDED) |
223 | retval = 1; | |
224 | ||
225 | return retval; | |
226 | } | |
227 | ||
ad3c36a5 RW |
228 | /** |
229 | * __rpm_callback - Run a given runtime PM callback for a given device. | |
230 | * @cb: Runtime PM callback to run. | |
231 | * @dev: Device to run the callback for. | |
232 | */ | |
233 | static int __rpm_callback(int (*cb)(struct device *), struct device *dev) | |
234 | __releases(&dev->power.lock) __acquires(&dev->power.lock) | |
235 | { | |
236 | int retval; | |
237 | ||
238 | if (dev->power.irq_safe) | |
239 | spin_unlock(&dev->power.lock); | |
240 | else | |
241 | spin_unlock_irq(&dev->power.lock); | |
242 | ||
243 | retval = cb(dev); | |
244 | ||
245 | if (dev->power.irq_safe) | |
246 | spin_lock(&dev->power.lock); | |
247 | else | |
248 | spin_lock_irq(&dev->power.lock); | |
249 | ||
250 | return retval; | |
251 | } | |
252 | ||
1bfee5bc | 253 | /** |
140a6c94 | 254 | * rpm_idle - Notify device bus type if the device can be suspended. |
1bfee5bc AS |
255 | * @dev: Device to notify the bus type about. |
256 | * @rpmflags: Flag bits. | |
257 | * | |
62052ab1 | 258 | * Check if the device's runtime PM status allows it to be suspended. If |
1bfee5bc AS |
259 | * another idle notification has been started earlier, return immediately. If |
260 | * the RPM_ASYNC flag is set then queue an idle-notification request; otherwise | |
261 | * run the ->runtime_idle() callback directly. | |
262 | * | |
263 | * This function must be called under dev->power.lock with interrupts disabled. | |
264 | */ | |
140a6c94 | 265 | static int rpm_idle(struct device *dev, int rpmflags) |
1bfee5bc | 266 | { |
71c63122 | 267 | int (*callback)(struct device *); |
1bfee5bc AS |
268 | int retval; |
269 | ||
c3dc2f14 | 270 | trace_rpm_idle(dev, rpmflags); |
1bfee5bc AS |
271 | retval = rpm_check_suspend_allowed(dev); |
272 | if (retval < 0) | |
273 | ; /* Conditions are wrong. */ | |
274 | ||
275 | /* Idle notifications are allowed only in the RPM_ACTIVE state. */ | |
276 | else if (dev->power.runtime_status != RPM_ACTIVE) | |
277 | retval = -EAGAIN; | |
278 | ||
279 | /* | |
280 | * Any pending request other than an idle notification takes | |
281 | * precedence over us, except that the timer may be running. | |
282 | */ | |
283 | else if (dev->power.request_pending && | |
284 | dev->power.request > RPM_REQ_IDLE) | |
285 | retval = -EAGAIN; | |
286 | ||
287 | /* Act as though RPM_NOWAIT is always set. */ | |
288 | else if (dev->power.idle_notification) | |
289 | retval = -EINPROGRESS; | |
5e928f77 RW |
290 | if (retval) |
291 | goto out; | |
292 | ||
1bfee5bc AS |
293 | /* Pending requests need to be canceled. */ |
294 | dev->power.request = RPM_REQ_NONE; | |
295 | ||
45f0a85c | 296 | if (dev->power.no_callbacks) |
7490e442 | 297 | goto out; |
7490e442 | 298 | |
1bfee5bc AS |
299 | /* Carry out an asynchronous or a synchronous idle notification. */ |
300 | if (rpmflags & RPM_ASYNC) { | |
301 | dev->power.request = RPM_REQ_IDLE; | |
302 | if (!dev->power.request_pending) { | |
303 | dev->power.request_pending = true; | |
304 | queue_work(pm_wq, &dev->power.work); | |
5e928f77 | 305 | } |
45f0a85c RW |
306 | trace_rpm_return_int(dev, _THIS_IP_, 0); |
307 | return 0; | |
5e928f77 RW |
308 | } |
309 | ||
310 | dev->power.idle_notification = true; | |
311 | ||
564b905a RW |
312 | if (dev->pm_domain) |
313 | callback = dev->pm_domain->ops.runtime_idle; | |
4d27e9dc | 314 | else if (dev->type && dev->type->pm) |
71c63122 RW |
315 | callback = dev->type->pm->runtime_idle; |
316 | else if (dev->class && dev->class->pm) | |
317 | callback = dev->class->pm->runtime_idle; | |
9659cc06 RW |
318 | else if (dev->bus && dev->bus->pm) |
319 | callback = dev->bus->pm->runtime_idle; | |
71c63122 RW |
320 | else |
321 | callback = NULL; | |
a6ab7aa9 | 322 | |
35cd133c RW |
323 | if (!callback && dev->driver && dev->driver->pm) |
324 | callback = dev->driver->pm->runtime_idle; | |
325 | ||
ad3c36a5 | 326 | if (callback) |
45f0a85c | 327 | retval = __rpm_callback(callback, dev); |
5e928f77 RW |
328 | |
329 | dev->power.idle_notification = false; | |
330 | wake_up_all(&dev->power.wait_queue); | |
331 | ||
332 | out: | |
c3dc2f14 | 333 | trace_rpm_return_int(dev, _THIS_IP_, retval); |
45f0a85c | 334 | return retval ? retval : rpm_suspend(dev, rpmflags); |
5e928f77 RW |
335 | } |
336 | ||
71c63122 RW |
337 | /** |
338 | * rpm_callback - Run a given runtime PM callback for a given device. | |
339 | * @cb: Runtime PM callback to run. | |
340 | * @dev: Device to run the callback for. | |
341 | */ | |
342 | static int rpm_callback(int (*cb)(struct device *), struct device *dev) | |
71c63122 RW |
343 | { |
344 | int retval; | |
345 | ||
346 | if (!cb) | |
347 | return -ENOSYS; | |
348 | ||
db88175f ML |
349 | if (dev->power.memalloc_noio) { |
350 | unsigned int noio_flag; | |
351 | ||
352 | /* | |
353 | * Deadlock might be caused if memory allocation with | |
354 | * GFP_KERNEL happens inside runtime_suspend and | |
355 | * runtime_resume callbacks of one block device's | |
356 | * ancestor or the block device itself. Network | |
357 | * device might be thought as part of iSCSI block | |
358 | * device, so network device and its ancestor should | |
359 | * be marked as memalloc_noio too. | |
360 | */ | |
361 | noio_flag = memalloc_noio_save(); | |
362 | retval = __rpm_callback(cb, dev); | |
363 | memalloc_noio_restore(noio_flag); | |
364 | } else { | |
365 | retval = __rpm_callback(cb, dev); | |
366 | } | |
71c63122 | 367 | |
71c63122 | 368 | dev->power.runtime_error = retval; |
632e270e | 369 | return retval != -EACCES ? retval : -EIO; |
71c63122 RW |
370 | } |
371 | ||
5e928f77 | 372 | /** |
62052ab1 | 373 | * rpm_suspend - Carry out runtime suspend of given device. |
5e928f77 | 374 | * @dev: Device to suspend. |
3f9af051 | 375 | * @rpmflags: Flag bits. |
5e928f77 | 376 | * |
47d8f0ba ML |
377 | * Check if the device's runtime PM status allows it to be suspended. |
378 | * Cancel a pending idle notification, autosuspend or suspend. If | |
379 | * another suspend has been started earlier, either return immediately | |
380 | * or wait for it to finish, depending on the RPM_NOWAIT and RPM_ASYNC | |
381 | * flags. If the RPM_ASYNC flag is set then queue a suspend request; | |
857b36c7 ML |
382 | * otherwise run the ->runtime_suspend() callback directly. When |
383 | * ->runtime_suspend succeeded, if a deferred resume was requested while | |
384 | * the callback was running then carry it out, otherwise send an idle | |
385 | * notification for its parent (if the suspend succeeded and both | |
386 | * ignore_children of parent->power and irq_safe of dev->power are not set). | |
886486b7 AS |
387 | * If ->runtime_suspend failed with -EAGAIN or -EBUSY, and if the RPM_AUTO |
388 | * flag is set and the next autosuspend-delay expiration time is in the | |
389 | * future, schedule another autosuspend attempt. | |
5e928f77 RW |
390 | * |
391 | * This function must be called under dev->power.lock with interrupts disabled. | |
392 | */ | |
140a6c94 | 393 | static int rpm_suspend(struct device *dev, int rpmflags) |
5e928f77 RW |
394 | __releases(&dev->power.lock) __acquires(&dev->power.lock) |
395 | { | |
71c63122 | 396 | int (*callback)(struct device *); |
5e928f77 | 397 | struct device *parent = NULL; |
1bfee5bc | 398 | int retval; |
5e928f77 | 399 | |
c3dc2f14 | 400 | trace_rpm_suspend(dev, rpmflags); |
5e928f77 RW |
401 | |
402 | repeat: | |
1bfee5bc | 403 | retval = rpm_check_suspend_allowed(dev); |
5e928f77 | 404 | |
1bfee5bc AS |
405 | if (retval < 0) |
406 | ; /* Conditions are wrong. */ | |
407 | ||
408 | /* Synchronous suspends are not allowed in the RPM_RESUMING state. */ | |
409 | else if (dev->power.runtime_status == RPM_RESUMING && | |
410 | !(rpmflags & RPM_ASYNC)) | |
5e928f77 | 411 | retval = -EAGAIN; |
1bfee5bc | 412 | if (retval) |
5e928f77 | 413 | goto out; |
5e928f77 | 414 | |
15bcb91d AS |
415 | /* If the autosuspend_delay time hasn't expired yet, reschedule. */ |
416 | if ((rpmflags & RPM_AUTO) | |
417 | && dev->power.runtime_status != RPM_SUSPENDING) { | |
418 | unsigned long expires = pm_runtime_autosuspend_expiration(dev); | |
419 | ||
420 | if (expires != 0) { | |
421 | /* Pending requests need to be canceled. */ | |
422 | dev->power.request = RPM_REQ_NONE; | |
423 | ||
424 | /* | |
425 | * Optimization: If the timer is already running and is | |
426 | * set to expire at or before the autosuspend delay, | |
427 | * avoid the overhead of resetting it. Just let it | |
428 | * expire; pm_suspend_timer_fn() will take care of the | |
429 | * rest. | |
430 | */ | |
431 | if (!(dev->power.timer_expires && time_before_eq( | |
432 | dev->power.timer_expires, expires))) { | |
433 | dev->power.timer_expires = expires; | |
434 | mod_timer(&dev->power.suspend_timer, expires); | |
435 | } | |
436 | dev->power.timer_autosuspends = 1; | |
437 | goto out; | |
438 | } | |
439 | } | |
440 | ||
5e928f77 RW |
441 | /* Other scheduled or pending requests need to be canceled. */ |
442 | pm_runtime_cancel_pending(dev); | |
443 | ||
5e928f77 RW |
444 | if (dev->power.runtime_status == RPM_SUSPENDING) { |
445 | DEFINE_WAIT(wait); | |
446 | ||
1bfee5bc | 447 | if (rpmflags & (RPM_ASYNC | RPM_NOWAIT)) { |
5e928f77 RW |
448 | retval = -EINPROGRESS; |
449 | goto out; | |
450 | } | |
451 | ||
ad3c36a5 RW |
452 | if (dev->power.irq_safe) { |
453 | spin_unlock(&dev->power.lock); | |
454 | ||
455 | cpu_relax(); | |
456 | ||
457 | spin_lock(&dev->power.lock); | |
458 | goto repeat; | |
459 | } | |
460 | ||
5e928f77 RW |
461 | /* Wait for the other suspend running in parallel with us. */ |
462 | for (;;) { | |
463 | prepare_to_wait(&dev->power.wait_queue, &wait, | |
464 | TASK_UNINTERRUPTIBLE); | |
465 | if (dev->power.runtime_status != RPM_SUSPENDING) | |
466 | break; | |
467 | ||
468 | spin_unlock_irq(&dev->power.lock); | |
469 | ||
470 | schedule(); | |
471 | ||
472 | spin_lock_irq(&dev->power.lock); | |
473 | } | |
474 | finish_wait(&dev->power.wait_queue, &wait); | |
475 | goto repeat; | |
476 | } | |
477 | ||
7490e442 AS |
478 | if (dev->power.no_callbacks) |
479 | goto no_callback; /* Assume success. */ | |
480 | ||
1bfee5bc AS |
481 | /* Carry out an asynchronous or a synchronous suspend. */ |
482 | if (rpmflags & RPM_ASYNC) { | |
15bcb91d AS |
483 | dev->power.request = (rpmflags & RPM_AUTO) ? |
484 | RPM_REQ_AUTOSUSPEND : RPM_REQ_SUSPEND; | |
1bfee5bc AS |
485 | if (!dev->power.request_pending) { |
486 | dev->power.request_pending = true; | |
487 | queue_work(pm_wq, &dev->power.work); | |
488 | } | |
489 | goto out; | |
490 | } | |
491 | ||
8d4b9d1b | 492 | __update_runtime_status(dev, RPM_SUSPENDING); |
5e928f77 | 493 | |
564b905a RW |
494 | if (dev->pm_domain) |
495 | callback = dev->pm_domain->ops.runtime_suspend; | |
4d27e9dc | 496 | else if (dev->type && dev->type->pm) |
71c63122 RW |
497 | callback = dev->type->pm->runtime_suspend; |
498 | else if (dev->class && dev->class->pm) | |
499 | callback = dev->class->pm->runtime_suspend; | |
9659cc06 RW |
500 | else if (dev->bus && dev->bus->pm) |
501 | callback = dev->bus->pm->runtime_suspend; | |
71c63122 RW |
502 | else |
503 | callback = NULL; | |
5e928f77 | 504 | |
35cd133c RW |
505 | if (!callback && dev->driver && dev->driver->pm) |
506 | callback = dev->driver->pm->runtime_suspend; | |
507 | ||
71c63122 | 508 | retval = rpm_callback(callback, dev); |
00dc9ad1 RW |
509 | if (retval) |
510 | goto fail; | |
886486b7 | 511 | |
7490e442 | 512 | no_callback: |
857b36c7 ML |
513 | __update_runtime_status(dev, RPM_SUSPENDED); |
514 | pm_runtime_deactivate_timer(dev); | |
5e928f77 | 515 | |
857b36c7 ML |
516 | if (dev->parent) { |
517 | parent = dev->parent; | |
518 | atomic_add_unless(&parent->power.child_count, -1, 0); | |
5e928f77 RW |
519 | } |
520 | wake_up_all(&dev->power.wait_queue); | |
521 | ||
522 | if (dev->power.deferred_resume) { | |
58a34de7 | 523 | dev->power.deferred_resume = false; |
140a6c94 | 524 | rpm_resume(dev, 0); |
5e928f77 RW |
525 | retval = -EAGAIN; |
526 | goto out; | |
527 | } | |
528 | ||
c3810c88 | 529 | /* Maybe the parent is now able to suspend. */ |
c7b61de5 | 530 | if (parent && !parent->power.ignore_children && !dev->power.irq_safe) { |
c3810c88 | 531 | spin_unlock(&dev->power.lock); |
5e928f77 | 532 | |
c3810c88 AS |
533 | spin_lock(&parent->power.lock); |
534 | rpm_idle(parent, RPM_ASYNC); | |
535 | spin_unlock(&parent->power.lock); | |
5e928f77 | 536 | |
c3810c88 | 537 | spin_lock(&dev->power.lock); |
5e928f77 RW |
538 | } |
539 | ||
540 | out: | |
c3dc2f14 | 541 | trace_rpm_return_int(dev, _THIS_IP_, retval); |
5e928f77 RW |
542 | |
543 | return retval; | |
00dc9ad1 RW |
544 | |
545 | fail: | |
546 | __update_runtime_status(dev, RPM_ACTIVE); | |
00dc9ad1 | 547 | dev->power.deferred_resume = false; |
f2791d73 AS |
548 | wake_up_all(&dev->power.wait_queue); |
549 | ||
00dc9ad1 RW |
550 | if (retval == -EAGAIN || retval == -EBUSY) { |
551 | dev->power.runtime_error = 0; | |
552 | ||
553 | /* | |
554 | * If the callback routine failed an autosuspend, and | |
555 | * if the last_busy time has been updated so that there | |
556 | * is a new autosuspend expiration time, automatically | |
557 | * reschedule another autosuspend. | |
558 | */ | |
559 | if ((rpmflags & RPM_AUTO) && | |
560 | pm_runtime_autosuspend_expiration(dev) != 0) | |
561 | goto repeat; | |
562 | } else { | |
563 | pm_runtime_cancel_pending(dev); | |
564 | } | |
00dc9ad1 | 565 | goto out; |
5e928f77 RW |
566 | } |
567 | ||
568 | /** | |
62052ab1 | 569 | * rpm_resume - Carry out runtime resume of given device. |
5e928f77 | 570 | * @dev: Device to resume. |
3f9af051 | 571 | * @rpmflags: Flag bits. |
5e928f77 | 572 | * |
62052ab1 | 573 | * Check if the device's runtime PM status allows it to be resumed. Cancel |
1bfee5bc | 574 | * any scheduled or pending requests. If another resume has been started |
25985edc | 575 | * earlier, either return immediately or wait for it to finish, depending on the |
1bfee5bc AS |
576 | * RPM_NOWAIT and RPM_ASYNC flags. Similarly, if there's a suspend running in |
577 | * parallel with this function, either tell the other process to resume after | |
578 | * suspending (deferred_resume) or wait for it to finish. If the RPM_ASYNC | |
579 | * flag is set then queue a resume request; otherwise run the | |
580 | * ->runtime_resume() callback directly. Queue an idle notification for the | |
581 | * device if the resume succeeded. | |
5e928f77 RW |
582 | * |
583 | * This function must be called under dev->power.lock with interrupts disabled. | |
584 | */ | |
140a6c94 | 585 | static int rpm_resume(struct device *dev, int rpmflags) |
5e928f77 RW |
586 | __releases(&dev->power.lock) __acquires(&dev->power.lock) |
587 | { | |
71c63122 | 588 | int (*callback)(struct device *); |
5e928f77 RW |
589 | struct device *parent = NULL; |
590 | int retval = 0; | |
591 | ||
c3dc2f14 | 592 | trace_rpm_resume(dev, rpmflags); |
5e928f77 RW |
593 | |
594 | repeat: | |
1bfee5bc | 595 | if (dev->power.runtime_error) |
5e928f77 | 596 | retval = -EINVAL; |
6f3c77b0 KH |
597 | else if (dev->power.disable_depth == 1 && dev->power.is_suspended |
598 | && dev->power.runtime_status == RPM_ACTIVE) | |
599 | retval = 1; | |
1bfee5bc | 600 | else if (dev->power.disable_depth > 0) |
632e270e | 601 | retval = -EACCES; |
1bfee5bc | 602 | if (retval) |
5e928f77 | 603 | goto out; |
5e928f77 | 604 | |
15bcb91d AS |
605 | /* |
606 | * Other scheduled or pending requests need to be canceled. Small | |
607 | * optimization: If an autosuspend timer is running, leave it running | |
608 | * rather than cancelling it now only to restart it again in the near | |
609 | * future. | |
610 | */ | |
611 | dev->power.request = RPM_REQ_NONE; | |
612 | if (!dev->power.timer_autosuspends) | |
613 | pm_runtime_deactivate_timer(dev); | |
5e928f77 | 614 | |
1bfee5bc | 615 | if (dev->power.runtime_status == RPM_ACTIVE) { |
5e928f77 | 616 | retval = 1; |
5e928f77 | 617 | goto out; |
1bfee5bc | 618 | } |
5e928f77 RW |
619 | |
620 | if (dev->power.runtime_status == RPM_RESUMING | |
621 | || dev->power.runtime_status == RPM_SUSPENDING) { | |
622 | DEFINE_WAIT(wait); | |
623 | ||
1bfee5bc | 624 | if (rpmflags & (RPM_ASYNC | RPM_NOWAIT)) { |
5e928f77 RW |
625 | if (dev->power.runtime_status == RPM_SUSPENDING) |
626 | dev->power.deferred_resume = true; | |
1bfee5bc AS |
627 | else |
628 | retval = -EINPROGRESS; | |
5e928f77 RW |
629 | goto out; |
630 | } | |
631 | ||
ad3c36a5 RW |
632 | if (dev->power.irq_safe) { |
633 | spin_unlock(&dev->power.lock); | |
634 | ||
635 | cpu_relax(); | |
636 | ||
637 | spin_lock(&dev->power.lock); | |
638 | goto repeat; | |
639 | } | |
640 | ||
5e928f77 RW |
641 | /* Wait for the operation carried out in parallel with us. */ |
642 | for (;;) { | |
643 | prepare_to_wait(&dev->power.wait_queue, &wait, | |
644 | TASK_UNINTERRUPTIBLE); | |
645 | if (dev->power.runtime_status != RPM_RESUMING | |
646 | && dev->power.runtime_status != RPM_SUSPENDING) | |
647 | break; | |
648 | ||
649 | spin_unlock_irq(&dev->power.lock); | |
650 | ||
651 | schedule(); | |
652 | ||
653 | spin_lock_irq(&dev->power.lock); | |
654 | } | |
655 | finish_wait(&dev->power.wait_queue, &wait); | |
656 | goto repeat; | |
657 | } | |
658 | ||
7490e442 AS |
659 | /* |
660 | * See if we can skip waking up the parent. This is safe only if | |
661 | * power.no_callbacks is set, because otherwise we don't know whether | |
662 | * the resume will actually succeed. | |
663 | */ | |
664 | if (dev->power.no_callbacks && !parent && dev->parent) { | |
d63be5f9 | 665 | spin_lock_nested(&dev->parent->power.lock, SINGLE_DEPTH_NESTING); |
7490e442 AS |
666 | if (dev->parent->power.disable_depth > 0 |
667 | || dev->parent->power.ignore_children | |
668 | || dev->parent->power.runtime_status == RPM_ACTIVE) { | |
669 | atomic_inc(&dev->parent->power.child_count); | |
670 | spin_unlock(&dev->parent->power.lock); | |
7f321c26 | 671 | retval = 1; |
7490e442 AS |
672 | goto no_callback; /* Assume success. */ |
673 | } | |
674 | spin_unlock(&dev->parent->power.lock); | |
675 | } | |
676 | ||
1bfee5bc AS |
677 | /* Carry out an asynchronous or a synchronous resume. */ |
678 | if (rpmflags & RPM_ASYNC) { | |
679 | dev->power.request = RPM_REQ_RESUME; | |
680 | if (!dev->power.request_pending) { | |
681 | dev->power.request_pending = true; | |
682 | queue_work(pm_wq, &dev->power.work); | |
683 | } | |
684 | retval = 0; | |
685 | goto out; | |
686 | } | |
687 | ||
5e928f77 RW |
688 | if (!parent && dev->parent) { |
689 | /* | |
c7b61de5 AS |
690 | * Increment the parent's usage counter and resume it if |
691 | * necessary. Not needed if dev is irq-safe; then the | |
692 | * parent is permanently resumed. | |
5e928f77 RW |
693 | */ |
694 | parent = dev->parent; | |
c7b61de5 AS |
695 | if (dev->power.irq_safe) |
696 | goto skip_parent; | |
862f89b3 | 697 | spin_unlock(&dev->power.lock); |
5e928f77 RW |
698 | |
699 | pm_runtime_get_noresume(parent); | |
700 | ||
862f89b3 | 701 | spin_lock(&parent->power.lock); |
5e928f77 | 702 | /* |
62052ab1 | 703 | * We can resume if the parent's runtime PM is disabled or it |
5e928f77 RW |
704 | * is set to ignore children. |
705 | */ | |
706 | if (!parent->power.disable_depth | |
707 | && !parent->power.ignore_children) { | |
140a6c94 | 708 | rpm_resume(parent, 0); |
5e928f77 RW |
709 | if (parent->power.runtime_status != RPM_ACTIVE) |
710 | retval = -EBUSY; | |
711 | } | |
862f89b3 | 712 | spin_unlock(&parent->power.lock); |
5e928f77 | 713 | |
862f89b3 | 714 | spin_lock(&dev->power.lock); |
5e928f77 RW |
715 | if (retval) |
716 | goto out; | |
717 | goto repeat; | |
718 | } | |
c7b61de5 | 719 | skip_parent: |
5e928f77 | 720 | |
7490e442 AS |
721 | if (dev->power.no_callbacks) |
722 | goto no_callback; /* Assume success. */ | |
723 | ||
8d4b9d1b | 724 | __update_runtime_status(dev, RPM_RESUMING); |
5e928f77 | 725 | |
564b905a RW |
726 | if (dev->pm_domain) |
727 | callback = dev->pm_domain->ops.runtime_resume; | |
4d27e9dc | 728 | else if (dev->type && dev->type->pm) |
71c63122 RW |
729 | callback = dev->type->pm->runtime_resume; |
730 | else if (dev->class && dev->class->pm) | |
731 | callback = dev->class->pm->runtime_resume; | |
9659cc06 RW |
732 | else if (dev->bus && dev->bus->pm) |
733 | callback = dev->bus->pm->runtime_resume; | |
71c63122 RW |
734 | else |
735 | callback = NULL; | |
5e928f77 | 736 | |
35cd133c RW |
737 | if (!callback && dev->driver && dev->driver->pm) |
738 | callback = dev->driver->pm->runtime_resume; | |
739 | ||
71c63122 | 740 | retval = rpm_callback(callback, dev); |
5e928f77 | 741 | if (retval) { |
8d4b9d1b | 742 | __update_runtime_status(dev, RPM_SUSPENDED); |
5e928f77 RW |
743 | pm_runtime_cancel_pending(dev); |
744 | } else { | |
7490e442 | 745 | no_callback: |
8d4b9d1b | 746 | __update_runtime_status(dev, RPM_ACTIVE); |
5e928f77 RW |
747 | if (parent) |
748 | atomic_inc(&parent->power.child_count); | |
749 | } | |
750 | wake_up_all(&dev->power.wait_queue); | |
751 | ||
7f321c26 | 752 | if (retval >= 0) |
140a6c94 | 753 | rpm_idle(dev, RPM_ASYNC); |
5e928f77 RW |
754 | |
755 | out: | |
c7b61de5 | 756 | if (parent && !dev->power.irq_safe) { |
5e928f77 RW |
757 | spin_unlock_irq(&dev->power.lock); |
758 | ||
759 | pm_runtime_put(parent); | |
760 | ||
761 | spin_lock_irq(&dev->power.lock); | |
762 | } | |
763 | ||
c3dc2f14 | 764 | trace_rpm_return_int(dev, _THIS_IP_, retval); |
5e928f77 RW |
765 | |
766 | return retval; | |
767 | } | |
768 | ||
5e928f77 | 769 | /** |
62052ab1 | 770 | * pm_runtime_work - Universal runtime PM work function. |
5e928f77 RW |
771 | * @work: Work structure used for scheduling the execution of this function. |
772 | * | |
773 | * Use @work to get the device object the work is to be done for, determine what | |
62052ab1 | 774 | * is to be done and execute the appropriate runtime PM function. |
5e928f77 RW |
775 | */ |
776 | static void pm_runtime_work(struct work_struct *work) | |
777 | { | |
778 | struct device *dev = container_of(work, struct device, power.work); | |
779 | enum rpm_request req; | |
780 | ||
781 | spin_lock_irq(&dev->power.lock); | |
782 | ||
783 | if (!dev->power.request_pending) | |
784 | goto out; | |
785 | ||
786 | req = dev->power.request; | |
787 | dev->power.request = RPM_REQ_NONE; | |
788 | dev->power.request_pending = false; | |
789 | ||
790 | switch (req) { | |
791 | case RPM_REQ_NONE: | |
792 | break; | |
793 | case RPM_REQ_IDLE: | |
140a6c94 | 794 | rpm_idle(dev, RPM_NOWAIT); |
5e928f77 RW |
795 | break; |
796 | case RPM_REQ_SUSPEND: | |
140a6c94 | 797 | rpm_suspend(dev, RPM_NOWAIT); |
5e928f77 | 798 | break; |
15bcb91d AS |
799 | case RPM_REQ_AUTOSUSPEND: |
800 | rpm_suspend(dev, RPM_NOWAIT | RPM_AUTO); | |
801 | break; | |
5e928f77 | 802 | case RPM_REQ_RESUME: |
140a6c94 | 803 | rpm_resume(dev, RPM_NOWAIT); |
5e928f77 RW |
804 | break; |
805 | } | |
806 | ||
807 | out: | |
808 | spin_unlock_irq(&dev->power.lock); | |
809 | } | |
810 | ||
5e928f77 RW |
811 | /** |
812 | * pm_suspend_timer_fn - Timer function for pm_schedule_suspend(). | |
813 | * @data: Device pointer passed by pm_schedule_suspend(). | |
814 | * | |
1bfee5bc | 815 | * Check if the time is right and queue a suspend request. |
5e928f77 RW |
816 | */ |
817 | static void pm_suspend_timer_fn(unsigned long data) | |
818 | { | |
819 | struct device *dev = (struct device *)data; | |
820 | unsigned long flags; | |
821 | unsigned long expires; | |
822 | ||
823 | spin_lock_irqsave(&dev->power.lock, flags); | |
824 | ||
825 | expires = dev->power.timer_expires; | |
826 | /* If 'expire' is after 'jiffies' we've been called too early. */ | |
827 | if (expires > 0 && !time_after(expires, jiffies)) { | |
828 | dev->power.timer_expires = 0; | |
15bcb91d AS |
829 | rpm_suspend(dev, dev->power.timer_autosuspends ? |
830 | (RPM_ASYNC | RPM_AUTO) : RPM_ASYNC); | |
5e928f77 RW |
831 | } |
832 | ||
833 | spin_unlock_irqrestore(&dev->power.lock, flags); | |
834 | } | |
835 | ||
836 | /** | |
837 | * pm_schedule_suspend - Set up a timer to submit a suspend request in future. | |
838 | * @dev: Device to suspend. | |
839 | * @delay: Time to wait before submitting a suspend request, in milliseconds. | |
840 | */ | |
841 | int pm_schedule_suspend(struct device *dev, unsigned int delay) | |
842 | { | |
843 | unsigned long flags; | |
1bfee5bc | 844 | int retval; |
5e928f77 RW |
845 | |
846 | spin_lock_irqsave(&dev->power.lock, flags); | |
847 | ||
5e928f77 | 848 | if (!delay) { |
140a6c94 | 849 | retval = rpm_suspend(dev, RPM_ASYNC); |
5e928f77 RW |
850 | goto out; |
851 | } | |
852 | ||
1bfee5bc | 853 | retval = rpm_check_suspend_allowed(dev); |
5e928f77 RW |
854 | if (retval) |
855 | goto out; | |
856 | ||
1bfee5bc AS |
857 | /* Other scheduled or pending requests need to be canceled. */ |
858 | pm_runtime_cancel_pending(dev); | |
859 | ||
5e928f77 | 860 | dev->power.timer_expires = jiffies + msecs_to_jiffies(delay); |
1bfee5bc | 861 | dev->power.timer_expires += !dev->power.timer_expires; |
15bcb91d | 862 | dev->power.timer_autosuspends = 0; |
5e928f77 RW |
863 | mod_timer(&dev->power.suspend_timer, dev->power.timer_expires); |
864 | ||
865 | out: | |
866 | spin_unlock_irqrestore(&dev->power.lock, flags); | |
867 | ||
868 | return retval; | |
869 | } | |
870 | EXPORT_SYMBOL_GPL(pm_schedule_suspend); | |
871 | ||
5e928f77 | 872 | /** |
62052ab1 | 873 | * __pm_runtime_idle - Entry point for runtime idle operations. |
140a6c94 AS |
874 | * @dev: Device to send idle notification for. |
875 | * @rpmflags: Flag bits. | |
876 | * | |
877 | * If the RPM_GET_PUT flag is set, decrement the device's usage count and | |
878 | * return immediately if it is larger than zero. Then carry out an idle | |
879 | * notification, either synchronous or asynchronous. | |
880 | * | |
311aab73 CC |
881 | * This routine may be called in atomic context if the RPM_ASYNC flag is set, |
882 | * or if pm_runtime_irq_safe() has been called. | |
5e928f77 | 883 | */ |
140a6c94 | 884 | int __pm_runtime_idle(struct device *dev, int rpmflags) |
5e928f77 RW |
885 | { |
886 | unsigned long flags; | |
887 | int retval; | |
888 | ||
311aab73 CC |
889 | might_sleep_if(!(rpmflags & RPM_ASYNC) && !dev->power.irq_safe); |
890 | ||
140a6c94 AS |
891 | if (rpmflags & RPM_GET_PUT) { |
892 | if (!atomic_dec_and_test(&dev->power.usage_count)) | |
893 | return 0; | |
894 | } | |
895 | ||
5e928f77 | 896 | spin_lock_irqsave(&dev->power.lock, flags); |
140a6c94 | 897 | retval = rpm_idle(dev, rpmflags); |
5e928f77 RW |
898 | spin_unlock_irqrestore(&dev->power.lock, flags); |
899 | ||
900 | return retval; | |
901 | } | |
140a6c94 | 902 | EXPORT_SYMBOL_GPL(__pm_runtime_idle); |
5e928f77 RW |
903 | |
904 | /** | |
62052ab1 | 905 | * __pm_runtime_suspend - Entry point for runtime put/suspend operations. |
140a6c94 | 906 | * @dev: Device to suspend. |
3f9af051 | 907 | * @rpmflags: Flag bits. |
5e928f77 | 908 | * |
15bcb91d AS |
909 | * If the RPM_GET_PUT flag is set, decrement the device's usage count and |
910 | * return immediately if it is larger than zero. Then carry out a suspend, | |
911 | * either synchronous or asynchronous. | |
140a6c94 | 912 | * |
311aab73 CC |
913 | * This routine may be called in atomic context if the RPM_ASYNC flag is set, |
914 | * or if pm_runtime_irq_safe() has been called. | |
5e928f77 | 915 | */ |
140a6c94 | 916 | int __pm_runtime_suspend(struct device *dev, int rpmflags) |
5e928f77 | 917 | { |
140a6c94 | 918 | unsigned long flags; |
1d531c14 | 919 | int retval; |
5e928f77 | 920 | |
311aab73 CC |
921 | might_sleep_if(!(rpmflags & RPM_ASYNC) && !dev->power.irq_safe); |
922 | ||
15bcb91d AS |
923 | if (rpmflags & RPM_GET_PUT) { |
924 | if (!atomic_dec_and_test(&dev->power.usage_count)) | |
925 | return 0; | |
926 | } | |
927 | ||
140a6c94 AS |
928 | spin_lock_irqsave(&dev->power.lock, flags); |
929 | retval = rpm_suspend(dev, rpmflags); | |
930 | spin_unlock_irqrestore(&dev->power.lock, flags); | |
5e928f77 RW |
931 | |
932 | return retval; | |
933 | } | |
140a6c94 | 934 | EXPORT_SYMBOL_GPL(__pm_runtime_suspend); |
5e928f77 RW |
935 | |
936 | /** | |
62052ab1 | 937 | * __pm_runtime_resume - Entry point for runtime resume operations. |
140a6c94 | 938 | * @dev: Device to resume. |
3f9af051 | 939 | * @rpmflags: Flag bits. |
5e928f77 | 940 | * |
140a6c94 AS |
941 | * If the RPM_GET_PUT flag is set, increment the device's usage count. Then |
942 | * carry out a resume, either synchronous or asynchronous. | |
943 | * | |
311aab73 CC |
944 | * This routine may be called in atomic context if the RPM_ASYNC flag is set, |
945 | * or if pm_runtime_irq_safe() has been called. | |
5e928f77 | 946 | */ |
140a6c94 | 947 | int __pm_runtime_resume(struct device *dev, int rpmflags) |
5e928f77 | 948 | { |
140a6c94 AS |
949 | unsigned long flags; |
950 | int retval; | |
5e928f77 | 951 | |
311aab73 CC |
952 | might_sleep_if(!(rpmflags & RPM_ASYNC) && !dev->power.irq_safe); |
953 | ||
140a6c94 AS |
954 | if (rpmflags & RPM_GET_PUT) |
955 | atomic_inc(&dev->power.usage_count); | |
956 | ||
957 | spin_lock_irqsave(&dev->power.lock, flags); | |
958 | retval = rpm_resume(dev, rpmflags); | |
959 | spin_unlock_irqrestore(&dev->power.lock, flags); | |
5e928f77 RW |
960 | |
961 | return retval; | |
962 | } | |
140a6c94 | 963 | EXPORT_SYMBOL_GPL(__pm_runtime_resume); |
5e928f77 RW |
964 | |
965 | /** | |
62052ab1 | 966 | * __pm_runtime_set_status - Set runtime PM status of a device. |
5e928f77 | 967 | * @dev: Device to handle. |
62052ab1 | 968 | * @status: New runtime PM status of the device. |
5e928f77 | 969 | * |
62052ab1 | 970 | * If runtime PM of the device is disabled or its power.runtime_error field is |
5e928f77 RW |
971 | * different from zero, the status may be changed either to RPM_ACTIVE, or to |
972 | * RPM_SUSPENDED, as long as that reflects the actual state of the device. | |
973 | * However, if the device has a parent and the parent is not active, and the | |
974 | * parent's power.ignore_children flag is unset, the device's status cannot be | |
975 | * set to RPM_ACTIVE, so -EBUSY is returned in that case. | |
976 | * | |
977 | * If successful, __pm_runtime_set_status() clears the power.runtime_error field | |
978 | * and the device parent's counter of unsuspended children is modified to | |
979 | * reflect the new status. If the new status is RPM_SUSPENDED, an idle | |
980 | * notification request for the parent is submitted. | |
981 | */ | |
982 | int __pm_runtime_set_status(struct device *dev, unsigned int status) | |
983 | { | |
984 | struct device *parent = dev->parent; | |
985 | unsigned long flags; | |
986 | bool notify_parent = false; | |
987 | int error = 0; | |
988 | ||
989 | if (status != RPM_ACTIVE && status != RPM_SUSPENDED) | |
990 | return -EINVAL; | |
991 | ||
992 | spin_lock_irqsave(&dev->power.lock, flags); | |
993 | ||
994 | if (!dev->power.runtime_error && !dev->power.disable_depth) { | |
995 | error = -EAGAIN; | |
996 | goto out; | |
997 | } | |
998 | ||
999 | if (dev->power.runtime_status == status) | |
1000 | goto out_set; | |
1001 | ||
1002 | if (status == RPM_SUSPENDED) { | |
1003 | /* It always is possible to set the status to 'suspended'. */ | |
1004 | if (parent) { | |
1005 | atomic_add_unless(&parent->power.child_count, -1, 0); | |
1006 | notify_parent = !parent->power.ignore_children; | |
1007 | } | |
1008 | goto out_set; | |
1009 | } | |
1010 | ||
1011 | if (parent) { | |
bab636b9 | 1012 | spin_lock_nested(&parent->power.lock, SINGLE_DEPTH_NESTING); |
5e928f77 RW |
1013 | |
1014 | /* | |
1015 | * It is invalid to put an active child under a parent that is | |
62052ab1 | 1016 | * not active, has runtime PM enabled and the |
5e928f77 RW |
1017 | * 'power.ignore_children' flag unset. |
1018 | */ | |
1019 | if (!parent->power.disable_depth | |
1020 | && !parent->power.ignore_children | |
965c4ac0 | 1021 | && parent->power.runtime_status != RPM_ACTIVE) |
5e928f77 | 1022 | error = -EBUSY; |
965c4ac0 RW |
1023 | else if (dev->power.runtime_status == RPM_SUSPENDED) |
1024 | atomic_inc(&parent->power.child_count); | |
5e928f77 | 1025 | |
862f89b3 | 1026 | spin_unlock(&parent->power.lock); |
5e928f77 RW |
1027 | |
1028 | if (error) | |
1029 | goto out; | |
1030 | } | |
1031 | ||
1032 | out_set: | |
8d4b9d1b | 1033 | __update_runtime_status(dev, status); |
5e928f77 RW |
1034 | dev->power.runtime_error = 0; |
1035 | out: | |
1036 | spin_unlock_irqrestore(&dev->power.lock, flags); | |
1037 | ||
1038 | if (notify_parent) | |
1039 | pm_request_idle(parent); | |
1040 | ||
1041 | return error; | |
1042 | } | |
1043 | EXPORT_SYMBOL_GPL(__pm_runtime_set_status); | |
1044 | ||
1045 | /** | |
1046 | * __pm_runtime_barrier - Cancel pending requests and wait for completions. | |
1047 | * @dev: Device to handle. | |
1048 | * | |
1049 | * Flush all pending requests for the device from pm_wq and wait for all | |
62052ab1 | 1050 | * runtime PM operations involving the device in progress to complete. |
5e928f77 RW |
1051 | * |
1052 | * Should be called under dev->power.lock with interrupts disabled. | |
1053 | */ | |
1054 | static void __pm_runtime_barrier(struct device *dev) | |
1055 | { | |
1056 | pm_runtime_deactivate_timer(dev); | |
1057 | ||
1058 | if (dev->power.request_pending) { | |
1059 | dev->power.request = RPM_REQ_NONE; | |
1060 | spin_unlock_irq(&dev->power.lock); | |
1061 | ||
1062 | cancel_work_sync(&dev->power.work); | |
1063 | ||
1064 | spin_lock_irq(&dev->power.lock); | |
1065 | dev->power.request_pending = false; | |
1066 | } | |
1067 | ||
1068 | if (dev->power.runtime_status == RPM_SUSPENDING | |
1069 | || dev->power.runtime_status == RPM_RESUMING | |
1070 | || dev->power.idle_notification) { | |
1071 | DEFINE_WAIT(wait); | |
1072 | ||
1073 | /* Suspend, wake-up or idle notification in progress. */ | |
1074 | for (;;) { | |
1075 | prepare_to_wait(&dev->power.wait_queue, &wait, | |
1076 | TASK_UNINTERRUPTIBLE); | |
1077 | if (dev->power.runtime_status != RPM_SUSPENDING | |
1078 | && dev->power.runtime_status != RPM_RESUMING | |
1079 | && !dev->power.idle_notification) | |
1080 | break; | |
1081 | spin_unlock_irq(&dev->power.lock); | |
1082 | ||
1083 | schedule(); | |
1084 | ||
1085 | spin_lock_irq(&dev->power.lock); | |
1086 | } | |
1087 | finish_wait(&dev->power.wait_queue, &wait); | |
1088 | } | |
1089 | } | |
1090 | ||
1091 | /** | |
1092 | * pm_runtime_barrier - Flush pending requests and wait for completions. | |
1093 | * @dev: Device to handle. | |
1094 | * | |
1095 | * Prevent the device from being suspended by incrementing its usage counter and | |
1096 | * if there's a pending resume request for the device, wake the device up. | |
1097 | * Next, make sure that all pending requests for the device have been flushed | |
62052ab1 | 1098 | * from pm_wq and wait for all runtime PM operations involving the device in |
5e928f77 RW |
1099 | * progress to complete. |
1100 | * | |
1101 | * Return value: | |
1102 | * 1, if there was a resume request pending and the device had to be woken up, | |
1103 | * 0, otherwise | |
1104 | */ | |
1105 | int pm_runtime_barrier(struct device *dev) | |
1106 | { | |
1107 | int retval = 0; | |
1108 | ||
1109 | pm_runtime_get_noresume(dev); | |
1110 | spin_lock_irq(&dev->power.lock); | |
1111 | ||
1112 | if (dev->power.request_pending | |
1113 | && dev->power.request == RPM_REQ_RESUME) { | |
140a6c94 | 1114 | rpm_resume(dev, 0); |
5e928f77 RW |
1115 | retval = 1; |
1116 | } | |
1117 | ||
1118 | __pm_runtime_barrier(dev); | |
1119 | ||
1120 | spin_unlock_irq(&dev->power.lock); | |
1121 | pm_runtime_put_noidle(dev); | |
1122 | ||
1123 | return retval; | |
1124 | } | |
1125 | EXPORT_SYMBOL_GPL(pm_runtime_barrier); | |
1126 | ||
1127 | /** | |
62052ab1 | 1128 | * __pm_runtime_disable - Disable runtime PM of a device. |
5e928f77 RW |
1129 | * @dev: Device to handle. |
1130 | * @check_resume: If set, check if there's a resume request for the device. | |
1131 | * | |
1132 | * Increment power.disable_depth for the device and if was zero previously, | |
62052ab1 | 1133 | * cancel all pending runtime PM requests for the device and wait for all |
5e928f77 | 1134 | * operations in progress to complete. The device can be either active or |
62052ab1 | 1135 | * suspended after its runtime PM has been disabled. |
5e928f77 RW |
1136 | * |
1137 | * If @check_resume is set and there's a resume request pending when | |
1138 | * __pm_runtime_disable() is called and power.disable_depth is zero, the | |
62052ab1 | 1139 | * function will wake up the device before disabling its runtime PM. |
5e928f77 RW |
1140 | */ |
1141 | void __pm_runtime_disable(struct device *dev, bool check_resume) | |
1142 | { | |
1143 | spin_lock_irq(&dev->power.lock); | |
1144 | ||
1145 | if (dev->power.disable_depth > 0) { | |
1146 | dev->power.disable_depth++; | |
1147 | goto out; | |
1148 | } | |
1149 | ||
1150 | /* | |
1151 | * Wake up the device if there's a resume request pending, because that | |
62052ab1 | 1152 | * means there probably is some I/O to process and disabling runtime PM |
5e928f77 RW |
1153 | * shouldn't prevent the device from processing the I/O. |
1154 | */ | |
1155 | if (check_resume && dev->power.request_pending | |
1156 | && dev->power.request == RPM_REQ_RESUME) { | |
1157 | /* | |
1158 | * Prevent suspends and idle notifications from being carried | |
1159 | * out after we have woken up the device. | |
1160 | */ | |
1161 | pm_runtime_get_noresume(dev); | |
1162 | ||
140a6c94 | 1163 | rpm_resume(dev, 0); |
5e928f77 RW |
1164 | |
1165 | pm_runtime_put_noidle(dev); | |
1166 | } | |
1167 | ||
1168 | if (!dev->power.disable_depth++) | |
1169 | __pm_runtime_barrier(dev); | |
1170 | ||
1171 | out: | |
1172 | spin_unlock_irq(&dev->power.lock); | |
1173 | } | |
1174 | EXPORT_SYMBOL_GPL(__pm_runtime_disable); | |
1175 | ||
1176 | /** | |
62052ab1 | 1177 | * pm_runtime_enable - Enable runtime PM of a device. |
5e928f77 RW |
1178 | * @dev: Device to handle. |
1179 | */ | |
1180 | void pm_runtime_enable(struct device *dev) | |
1181 | { | |
1182 | unsigned long flags; | |
1183 | ||
1184 | spin_lock_irqsave(&dev->power.lock, flags); | |
1185 | ||
1186 | if (dev->power.disable_depth > 0) | |
1187 | dev->power.disable_depth--; | |
1188 | else | |
1189 | dev_warn(dev, "Unbalanced %s!\n", __func__); | |
1190 | ||
1191 | spin_unlock_irqrestore(&dev->power.lock, flags); | |
1192 | } | |
1193 | EXPORT_SYMBOL_GPL(pm_runtime_enable); | |
1194 | ||
53823639 | 1195 | /** |
62052ab1 | 1196 | * pm_runtime_forbid - Block runtime PM of a device. |
53823639 RW |
1197 | * @dev: Device to handle. |
1198 | * | |
1199 | * Increase the device's usage count and clear its power.runtime_auto flag, | |
1200 | * so that it cannot be suspended at run time until pm_runtime_allow() is called | |
1201 | * for it. | |
1202 | */ | |
1203 | void pm_runtime_forbid(struct device *dev) | |
1204 | { | |
1205 | spin_lock_irq(&dev->power.lock); | |
1206 | if (!dev->power.runtime_auto) | |
1207 | goto out; | |
1208 | ||
1209 | dev->power.runtime_auto = false; | |
1210 | atomic_inc(&dev->power.usage_count); | |
140a6c94 | 1211 | rpm_resume(dev, 0); |
53823639 RW |
1212 | |
1213 | out: | |
1214 | spin_unlock_irq(&dev->power.lock); | |
1215 | } | |
1216 | EXPORT_SYMBOL_GPL(pm_runtime_forbid); | |
1217 | ||
1218 | /** | |
62052ab1 | 1219 | * pm_runtime_allow - Unblock runtime PM of a device. |
53823639 RW |
1220 | * @dev: Device to handle. |
1221 | * | |
1222 | * Decrease the device's usage count and set its power.runtime_auto flag. | |
1223 | */ | |
1224 | void pm_runtime_allow(struct device *dev) | |
1225 | { | |
1226 | spin_lock_irq(&dev->power.lock); | |
1227 | if (dev->power.runtime_auto) | |
1228 | goto out; | |
1229 | ||
1230 | dev->power.runtime_auto = true; | |
1231 | if (atomic_dec_and_test(&dev->power.usage_count)) | |
15bcb91d | 1232 | rpm_idle(dev, RPM_AUTO); |
53823639 RW |
1233 | |
1234 | out: | |
1235 | spin_unlock_irq(&dev->power.lock); | |
1236 | } | |
1237 | EXPORT_SYMBOL_GPL(pm_runtime_allow); | |
1238 | ||
7490e442 | 1239 | /** |
62052ab1 | 1240 | * pm_runtime_no_callbacks - Ignore runtime PM callbacks for a device. |
7490e442 AS |
1241 | * @dev: Device to handle. |
1242 | * | |
1243 | * Set the power.no_callbacks flag, which tells the PM core that this | |
62052ab1 RW |
1244 | * device is power-managed through its parent and has no runtime PM |
1245 | * callbacks of its own. The runtime sysfs attributes will be removed. | |
7490e442 AS |
1246 | */ |
1247 | void pm_runtime_no_callbacks(struct device *dev) | |
1248 | { | |
1249 | spin_lock_irq(&dev->power.lock); | |
1250 | dev->power.no_callbacks = 1; | |
1251 | spin_unlock_irq(&dev->power.lock); | |
1252 | if (device_is_registered(dev)) | |
1253 | rpm_sysfs_remove(dev); | |
1254 | } | |
1255 | EXPORT_SYMBOL_GPL(pm_runtime_no_callbacks); | |
1256 | ||
c7b61de5 AS |
1257 | /** |
1258 | * pm_runtime_irq_safe - Leave interrupts disabled during callbacks. | |
1259 | * @dev: Device to handle | |
1260 | * | |
1261 | * Set the power.irq_safe flag, which tells the PM core that the | |
1262 | * ->runtime_suspend() and ->runtime_resume() callbacks for this device should | |
1263 | * always be invoked with the spinlock held and interrupts disabled. It also | |
1264 | * causes the parent's usage counter to be permanently incremented, preventing | |
1265 | * the parent from runtime suspending -- otherwise an irq-safe child might have | |
1266 | * to wait for a non-irq-safe parent. | |
1267 | */ | |
1268 | void pm_runtime_irq_safe(struct device *dev) | |
1269 | { | |
1270 | if (dev->parent) | |
1271 | pm_runtime_get_sync(dev->parent); | |
1272 | spin_lock_irq(&dev->power.lock); | |
1273 | dev->power.irq_safe = 1; | |
1274 | spin_unlock_irq(&dev->power.lock); | |
1275 | } | |
1276 | EXPORT_SYMBOL_GPL(pm_runtime_irq_safe); | |
1277 | ||
15bcb91d AS |
1278 | /** |
1279 | * update_autosuspend - Handle a change to a device's autosuspend settings. | |
1280 | * @dev: Device to handle. | |
1281 | * @old_delay: The former autosuspend_delay value. | |
1282 | * @old_use: The former use_autosuspend value. | |
1283 | * | |
1284 | * Prevent runtime suspend if the new delay is negative and use_autosuspend is | |
1285 | * set; otherwise allow it. Send an idle notification if suspends are allowed. | |
1286 | * | |
1287 | * This function must be called under dev->power.lock with interrupts disabled. | |
1288 | */ | |
1289 | static void update_autosuspend(struct device *dev, int old_delay, int old_use) | |
1290 | { | |
1291 | int delay = dev->power.autosuspend_delay; | |
1292 | ||
1293 | /* Should runtime suspend be prevented now? */ | |
1294 | if (dev->power.use_autosuspend && delay < 0) { | |
1295 | ||
1296 | /* If it used to be allowed then prevent it. */ | |
1297 | if (!old_use || old_delay >= 0) { | |
1298 | atomic_inc(&dev->power.usage_count); | |
1299 | rpm_resume(dev, 0); | |
1300 | } | |
1301 | } | |
1302 | ||
1303 | /* Runtime suspend should be allowed now. */ | |
1304 | else { | |
1305 | ||
1306 | /* If it used to be prevented then allow it. */ | |
1307 | if (old_use && old_delay < 0) | |
1308 | atomic_dec(&dev->power.usage_count); | |
1309 | ||
1310 | /* Maybe we can autosuspend now. */ | |
1311 | rpm_idle(dev, RPM_AUTO); | |
1312 | } | |
1313 | } | |
1314 | ||
1315 | /** | |
1316 | * pm_runtime_set_autosuspend_delay - Set a device's autosuspend_delay value. | |
1317 | * @dev: Device to handle. | |
1318 | * @delay: Value of the new delay in milliseconds. | |
1319 | * | |
1320 | * Set the device's power.autosuspend_delay value. If it changes to negative | |
62052ab1 RW |
1321 | * and the power.use_autosuspend flag is set, prevent runtime suspends. If it |
1322 | * changes the other way, allow runtime suspends. | |
15bcb91d AS |
1323 | */ |
1324 | void pm_runtime_set_autosuspend_delay(struct device *dev, int delay) | |
1325 | { | |
1326 | int old_delay, old_use; | |
1327 | ||
1328 | spin_lock_irq(&dev->power.lock); | |
1329 | old_delay = dev->power.autosuspend_delay; | |
1330 | old_use = dev->power.use_autosuspend; | |
1331 | dev->power.autosuspend_delay = delay; | |
1332 | update_autosuspend(dev, old_delay, old_use); | |
1333 | spin_unlock_irq(&dev->power.lock); | |
1334 | } | |
1335 | EXPORT_SYMBOL_GPL(pm_runtime_set_autosuspend_delay); | |
1336 | ||
1337 | /** | |
1338 | * __pm_runtime_use_autosuspend - Set a device's use_autosuspend flag. | |
1339 | * @dev: Device to handle. | |
1340 | * @use: New value for use_autosuspend. | |
1341 | * | |
62052ab1 | 1342 | * Set the device's power.use_autosuspend flag, and allow or prevent runtime |
15bcb91d AS |
1343 | * suspends as needed. |
1344 | */ | |
1345 | void __pm_runtime_use_autosuspend(struct device *dev, bool use) | |
1346 | { | |
1347 | int old_delay, old_use; | |
1348 | ||
1349 | spin_lock_irq(&dev->power.lock); | |
1350 | old_delay = dev->power.autosuspend_delay; | |
1351 | old_use = dev->power.use_autosuspend; | |
1352 | dev->power.use_autosuspend = use; | |
1353 | update_autosuspend(dev, old_delay, old_use); | |
1354 | spin_unlock_irq(&dev->power.lock); | |
1355 | } | |
1356 | EXPORT_SYMBOL_GPL(__pm_runtime_use_autosuspend); | |
1357 | ||
5e928f77 | 1358 | /** |
62052ab1 | 1359 | * pm_runtime_init - Initialize runtime PM fields in given device object. |
5e928f77 RW |
1360 | * @dev: Device object to initialize. |
1361 | */ | |
1362 | void pm_runtime_init(struct device *dev) | |
1363 | { | |
5e928f77 RW |
1364 | dev->power.runtime_status = RPM_SUSPENDED; |
1365 | dev->power.idle_notification = false; | |
1366 | ||
1367 | dev->power.disable_depth = 1; | |
1368 | atomic_set(&dev->power.usage_count, 0); | |
1369 | ||
1370 | dev->power.runtime_error = 0; | |
1371 | ||
1372 | atomic_set(&dev->power.child_count, 0); | |
1373 | pm_suspend_ignore_children(dev, false); | |
53823639 | 1374 | dev->power.runtime_auto = true; |
5e928f77 RW |
1375 | |
1376 | dev->power.request_pending = false; | |
1377 | dev->power.request = RPM_REQ_NONE; | |
1378 | dev->power.deferred_resume = false; | |
8d4b9d1b | 1379 | dev->power.accounting_timestamp = jiffies; |
5e928f77 RW |
1380 | INIT_WORK(&dev->power.work, pm_runtime_work); |
1381 | ||
1382 | dev->power.timer_expires = 0; | |
1383 | setup_timer(&dev->power.suspend_timer, pm_suspend_timer_fn, | |
1384 | (unsigned long)dev); | |
1385 | ||
1386 | init_waitqueue_head(&dev->power.wait_queue); | |
1387 | } | |
1388 | ||
1389 | /** | |
1390 | * pm_runtime_remove - Prepare for removing a device from device hierarchy. | |
1391 | * @dev: Device object being removed from device hierarchy. | |
1392 | */ | |
1393 | void pm_runtime_remove(struct device *dev) | |
1394 | { | |
1395 | __pm_runtime_disable(dev, false); | |
1396 | ||
1397 | /* Change the status back to 'suspended' to match the initial status. */ | |
1398 | if (dev->power.runtime_status == RPM_ACTIVE) | |
1399 | pm_runtime_set_suspended(dev); | |
c7b61de5 | 1400 | if (dev->power.irq_safe && dev->parent) |
db28dfac | 1401 | pm_runtime_put(dev->parent); |
5e928f77 | 1402 | } |