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