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Commit | Line | Data |
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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 | ||
5b3cc15a | 10 | #include <linux/sched/mm.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> |
21d5c57b RW |
15 | |
16 | #include "../base.h" | |
7490e442 | 17 | #include "power.h" |
5e928f77 | 18 | |
dbcd2d72 | 19 | typedef int (*pm_callback_t)(struct device *); |
5f59df79 | 20 | |
dbcd2d72 | 21 | static pm_callback_t __rpm_get_callback(struct device *dev, size_t cb_offset) |
5f59df79 | 22 | { |
dbcd2d72 AH |
23 | pm_callback_t cb; |
24 | const struct dev_pm_ops *ops; | |
25 | ||
26 | if (dev->pm_domain) | |
27 | ops = &dev->pm_domain->ops; | |
28 | else if (dev->type && dev->type->pm) | |
29 | ops = dev->type->pm; | |
30 | else if (dev->class && dev->class->pm) | |
31 | ops = dev->class->pm; | |
32 | else if (dev->bus && dev->bus->pm) | |
33 | ops = dev->bus->pm; | |
34 | else | |
35 | ops = NULL; | |
36 | ||
37 | if (ops) | |
38 | cb = *(pm_callback_t *)((void *)ops + cb_offset); | |
39 | else | |
40 | cb = NULL; | |
41 | ||
42 | if (!cb && dev->driver && dev->driver->pm) | |
43 | cb = *(pm_callback_t *)((void *)dev->driver->pm + cb_offset); | |
44 | ||
45 | return cb; | |
5f59df79 UH |
46 | } |
47 | ||
dbcd2d72 AH |
48 | #define RPM_GET_CALLBACK(dev, callback) \ |
49 | __rpm_get_callback(dev, offsetof(struct dev_pm_ops, callback)) | |
50 | ||
140a6c94 | 51 | static int rpm_resume(struct device *dev, int rpmflags); |
7490e442 | 52 | static int rpm_suspend(struct device *dev, int rpmflags); |
5e928f77 | 53 | |
4769373c AS |
54 | /** |
55 | * update_pm_runtime_accounting - Update the time accounting of power states | |
56 | * @dev: Device to update the accounting for | |
57 | * | |
58 | * In order to be able to have time accounting of the various power states | |
59 | * (as used by programs such as PowerTOP to show the effectiveness of runtime | |
60 | * PM), we need to track the time spent in each state. | |
61 | * update_pm_runtime_accounting must be called each time before the | |
62 | * runtime_status field is updated, to account the time in the old state | |
63 | * correctly. | |
64 | */ | |
65 | void update_pm_runtime_accounting(struct device *dev) | |
66 | { | |
67 | unsigned long now = jiffies; | |
def0c0a3 | 68 | unsigned long delta; |
4769373c AS |
69 | |
70 | delta = now - dev->power.accounting_timestamp; | |
71 | ||
4769373c AS |
72 | dev->power.accounting_timestamp = now; |
73 | ||
74 | if (dev->power.disable_depth > 0) | |
75 | return; | |
76 | ||
77 | if (dev->power.runtime_status == RPM_SUSPENDED) | |
78 | dev->power.suspended_jiffies += delta; | |
79 | else | |
80 | dev->power.active_jiffies += delta; | |
81 | } | |
82 | ||
83 | static void __update_runtime_status(struct device *dev, enum rpm_status status) | |
84 | { | |
85 | update_pm_runtime_accounting(dev); | |
86 | dev->power.runtime_status = status; | |
87 | } | |
88 | ||
5e928f77 RW |
89 | /** |
90 | * pm_runtime_deactivate_timer - Deactivate given device's suspend timer. | |
91 | * @dev: Device to handle. | |
92 | */ | |
93 | static void pm_runtime_deactivate_timer(struct device *dev) | |
94 | { | |
95 | if (dev->power.timer_expires > 0) { | |
96 | del_timer(&dev->power.suspend_timer); | |
97 | dev->power.timer_expires = 0; | |
98 | } | |
99 | } | |
100 | ||
101 | /** | |
102 | * pm_runtime_cancel_pending - Deactivate suspend timer and cancel requests. | |
103 | * @dev: Device to handle. | |
104 | */ | |
105 | static void pm_runtime_cancel_pending(struct device *dev) | |
106 | { | |
107 | pm_runtime_deactivate_timer(dev); | |
108 | /* | |
109 | * In case there's a request pending, make sure its work function will | |
110 | * return without doing anything. | |
111 | */ | |
112 | dev->power.request = RPM_REQ_NONE; | |
113 | } | |
114 | ||
15bcb91d AS |
115 | /* |
116 | * pm_runtime_autosuspend_expiration - Get a device's autosuspend-delay expiration time. | |
117 | * @dev: Device to handle. | |
118 | * | |
119 | * Compute the autosuspend-delay expiration time based on the device's | |
120 | * power.last_busy time. If the delay has already expired or is disabled | |
121 | * (negative) or the power.use_autosuspend flag isn't set, return 0. | |
122 | * Otherwise return the expiration time in jiffies (adjusted to be nonzero). | |
123 | * | |
124 | * This function may be called either with or without dev->power.lock held. | |
125 | * Either way it can be racy, since power.last_busy may be updated at any time. | |
126 | */ | |
127 | unsigned long pm_runtime_autosuspend_expiration(struct device *dev) | |
128 | { | |
129 | int autosuspend_delay; | |
130 | long elapsed; | |
131 | unsigned long last_busy; | |
132 | unsigned long expires = 0; | |
133 | ||
134 | if (!dev->power.use_autosuspend) | |
135 | goto out; | |
136 | ||
6aa7de05 | 137 | autosuspend_delay = READ_ONCE(dev->power.autosuspend_delay); |
15bcb91d AS |
138 | if (autosuspend_delay < 0) |
139 | goto out; | |
140 | ||
6aa7de05 | 141 | last_busy = READ_ONCE(dev->power.last_busy); |
15bcb91d AS |
142 | elapsed = jiffies - last_busy; |
143 | if (elapsed < 0) | |
144 | goto out; /* jiffies has wrapped around. */ | |
145 | ||
146 | /* | |
147 | * If the autosuspend_delay is >= 1 second, align the timer by rounding | |
148 | * up to the nearest second. | |
149 | */ | |
150 | expires = last_busy + msecs_to_jiffies(autosuspend_delay); | |
151 | if (autosuspend_delay >= 1000) | |
152 | expires = round_jiffies(expires); | |
153 | expires += !expires; | |
154 | if (elapsed >= expires - last_busy) | |
155 | expires = 0; /* Already expired. */ | |
156 | ||
157 | out: | |
158 | return expires; | |
159 | } | |
160 | EXPORT_SYMBOL_GPL(pm_runtime_autosuspend_expiration); | |
161 | ||
e823407f ML |
162 | static int dev_memalloc_noio(struct device *dev, void *data) |
163 | { | |
164 | return dev->power.memalloc_noio; | |
165 | } | |
166 | ||
167 | /* | |
168 | * pm_runtime_set_memalloc_noio - Set a device's memalloc_noio flag. | |
169 | * @dev: Device to handle. | |
170 | * @enable: True for setting the flag and False for clearing the flag. | |
171 | * | |
172 | * Set the flag for all devices in the path from the device to the | |
173 | * root device in the device tree if @enable is true, otherwise clear | |
174 | * the flag for devices in the path whose siblings don't set the flag. | |
175 | * | |
176 | * The function should only be called by block device, or network | |
177 | * device driver for solving the deadlock problem during runtime | |
178 | * resume/suspend: | |
179 | * | |
180 | * If memory allocation with GFP_KERNEL is called inside runtime | |
181 | * resume/suspend callback of any one of its ancestors(or the | |
182 | * block device itself), the deadlock may be triggered inside the | |
183 | * memory allocation since it might not complete until the block | |
184 | * device becomes active and the involed page I/O finishes. The | |
185 | * situation is pointed out first by Alan Stern. Network device | |
186 | * are involved in iSCSI kind of situation. | |
187 | * | |
188 | * The lock of dev_hotplug_mutex is held in the function for handling | |
189 | * hotplug race because pm_runtime_set_memalloc_noio() may be called | |
190 | * in async probe(). | |
191 | * | |
192 | * The function should be called between device_add() and device_del() | |
193 | * on the affected device(block/network device). | |
194 | */ | |
195 | void pm_runtime_set_memalloc_noio(struct device *dev, bool enable) | |
196 | { | |
197 | static DEFINE_MUTEX(dev_hotplug_mutex); | |
198 | ||
199 | mutex_lock(&dev_hotplug_mutex); | |
200 | for (;;) { | |
201 | bool enabled; | |
202 | ||
203 | /* hold power lock since bitfield is not SMP-safe. */ | |
204 | spin_lock_irq(&dev->power.lock); | |
205 | enabled = dev->power.memalloc_noio; | |
206 | dev->power.memalloc_noio = enable; | |
207 | spin_unlock_irq(&dev->power.lock); | |
208 | ||
209 | /* | |
210 | * not need to enable ancestors any more if the device | |
211 | * has been enabled. | |
212 | */ | |
213 | if (enabled && enable) | |
214 | break; | |
215 | ||
216 | dev = dev->parent; | |
217 | ||
218 | /* | |
219 | * clear flag of the parent device only if all the | |
220 | * children don't set the flag because ancestor's | |
221 | * flag was set by any one of the descendants. | |
222 | */ | |
223 | if (!dev || (!enable && | |
224 | device_for_each_child(dev, NULL, | |
225 | dev_memalloc_noio))) | |
226 | break; | |
227 | } | |
228 | mutex_unlock(&dev_hotplug_mutex); | |
229 | } | |
230 | EXPORT_SYMBOL_GPL(pm_runtime_set_memalloc_noio); | |
231 | ||
5e928f77 | 232 | /** |
1bfee5bc AS |
233 | * rpm_check_suspend_allowed - Test whether a device may be suspended. |
234 | * @dev: Device to test. | |
5e928f77 | 235 | */ |
1bfee5bc | 236 | static int rpm_check_suspend_allowed(struct device *dev) |
5e928f77 RW |
237 | { |
238 | int retval = 0; | |
239 | ||
5e928f77 RW |
240 | if (dev->power.runtime_error) |
241 | retval = -EINVAL; | |
632e270e RW |
242 | else if (dev->power.disable_depth > 0) |
243 | retval = -EACCES; | |
244 | else if (atomic_read(&dev->power.usage_count) > 0) | |
5e928f77 | 245 | retval = -EAGAIN; |
62006c17 UH |
246 | else if (!dev->power.ignore_children && |
247 | atomic_read(&dev->power.child_count)) | |
5e928f77 | 248 | retval = -EBUSY; |
1bfee5bc AS |
249 | |
250 | /* Pending resume requests take precedence over suspends. */ | |
251 | else if ((dev->power.deferred_resume | |
78ca7c37 | 252 | && dev->power.runtime_status == RPM_SUSPENDING) |
1bfee5bc AS |
253 | || (dev->power.request_pending |
254 | && dev->power.request == RPM_REQ_RESUME)) | |
255 | retval = -EAGAIN; | |
0759e80b | 256 | else if (__dev_pm_qos_read_value(dev) == 0) |
55d7ec45 | 257 | retval = -EPERM; |
1bfee5bc AS |
258 | else if (dev->power.runtime_status == RPM_SUSPENDED) |
259 | retval = 1; | |
260 | ||
261 | return retval; | |
262 | } | |
263 | ||
21d5c57b RW |
264 | static int rpm_get_suppliers(struct device *dev) |
265 | { | |
266 | struct device_link *link; | |
267 | ||
268 | list_for_each_entry_rcu(link, &dev->links.suppliers, c_node) { | |
269 | int retval; | |
270 | ||
271 | if (!(link->flags & DL_FLAG_PM_RUNTIME)) | |
272 | continue; | |
273 | ||
274 | if (READ_ONCE(link->status) == DL_STATE_SUPPLIER_UNBIND || | |
275 | link->rpm_active) | |
276 | continue; | |
277 | ||
278 | retval = pm_runtime_get_sync(link->supplier); | |
31eb7431 RW |
279 | /* Ignore suppliers with disabled runtime PM. */ |
280 | if (retval < 0 && retval != -EACCES) { | |
21d5c57b RW |
281 | pm_runtime_put_noidle(link->supplier); |
282 | return retval; | |
283 | } | |
284 | link->rpm_active = true; | |
285 | } | |
286 | return 0; | |
287 | } | |
288 | ||
289 | static void rpm_put_suppliers(struct device *dev) | |
290 | { | |
291 | struct device_link *link; | |
292 | ||
293 | list_for_each_entry_rcu(link, &dev->links.suppliers, c_node) | |
294 | if (link->rpm_active && | |
295 | READ_ONCE(link->status) != DL_STATE_SUPPLIER_UNBIND) { | |
296 | pm_runtime_put(link->supplier); | |
297 | link->rpm_active = false; | |
298 | } | |
299 | } | |
300 | ||
ad3c36a5 RW |
301 | /** |
302 | * __rpm_callback - Run a given runtime PM callback for a given device. | |
303 | * @cb: Runtime PM callback to run. | |
304 | * @dev: Device to run the callback for. | |
305 | */ | |
306 | static int __rpm_callback(int (*cb)(struct device *), struct device *dev) | |
307 | __releases(&dev->power.lock) __acquires(&dev->power.lock) | |
308 | { | |
21d5c57b | 309 | int retval, idx; |
baa8809f | 310 | bool use_links = dev->power.links_count > 0; |
ad3c36a5 | 311 | |
21d5c57b | 312 | if (dev->power.irq_safe) { |
ad3c36a5 | 313 | spin_unlock(&dev->power.lock); |
21d5c57b | 314 | } else { |
ad3c36a5 RW |
315 | spin_unlock_irq(&dev->power.lock); |
316 | ||
21d5c57b RW |
317 | /* |
318 | * Resume suppliers if necessary. | |
319 | * | |
320 | * The device's runtime PM status cannot change until this | |
321 | * routine returns, so it is safe to read the status outside of | |
322 | * the lock. | |
323 | */ | |
baa8809f | 324 | if (use_links && dev->power.runtime_status == RPM_RESUMING) { |
21d5c57b RW |
325 | idx = device_links_read_lock(); |
326 | ||
327 | retval = rpm_get_suppliers(dev); | |
328 | if (retval) | |
329 | goto fail; | |
330 | ||
331 | device_links_read_unlock(idx); | |
332 | } | |
333 | } | |
334 | ||
ad3c36a5 RW |
335 | retval = cb(dev); |
336 | ||
21d5c57b | 337 | if (dev->power.irq_safe) { |
ad3c36a5 | 338 | spin_lock(&dev->power.lock); |
21d5c57b RW |
339 | } else { |
340 | /* | |
341 | * If the device is suspending and the callback has returned | |
342 | * success, drop the usage counters of the suppliers that have | |
343 | * been reference counted on its resume. | |
344 | * | |
345 | * Do that if resume fails too. | |
346 | */ | |
baa8809f RW |
347 | if (use_links |
348 | && ((dev->power.runtime_status == RPM_SUSPENDING && !retval) | |
349 | || (dev->power.runtime_status == RPM_RESUMING && retval))) { | |
21d5c57b RW |
350 | idx = device_links_read_lock(); |
351 | ||
352 | fail: | |
353 | rpm_put_suppliers(dev); | |
354 | ||
355 | device_links_read_unlock(idx); | |
356 | } | |
357 | ||
ad3c36a5 | 358 | spin_lock_irq(&dev->power.lock); |
21d5c57b | 359 | } |
ad3c36a5 RW |
360 | |
361 | return retval; | |
362 | } | |
363 | ||
1bfee5bc | 364 | /** |
140a6c94 | 365 | * rpm_idle - Notify device bus type if the device can be suspended. |
1bfee5bc AS |
366 | * @dev: Device to notify the bus type about. |
367 | * @rpmflags: Flag bits. | |
368 | * | |
62052ab1 | 369 | * Check if the device's runtime PM status allows it to be suspended. If |
1bfee5bc AS |
370 | * another idle notification has been started earlier, return immediately. If |
371 | * the RPM_ASYNC flag is set then queue an idle-notification request; otherwise | |
d66e6db2 UH |
372 | * run the ->runtime_idle() callback directly. If the ->runtime_idle callback |
373 | * doesn't exist or if it returns 0, call rpm_suspend with the RPM_AUTO flag. | |
1bfee5bc AS |
374 | * |
375 | * This function must be called under dev->power.lock with interrupts disabled. | |
376 | */ | |
140a6c94 | 377 | static int rpm_idle(struct device *dev, int rpmflags) |
1bfee5bc | 378 | { |
71c63122 | 379 | int (*callback)(struct device *); |
1bfee5bc AS |
380 | int retval; |
381 | ||
d7737ce9 | 382 | trace_rpm_idle_rcuidle(dev, rpmflags); |
1bfee5bc AS |
383 | retval = rpm_check_suspend_allowed(dev); |
384 | if (retval < 0) | |
385 | ; /* Conditions are wrong. */ | |
386 | ||
387 | /* Idle notifications are allowed only in the RPM_ACTIVE state. */ | |
388 | else if (dev->power.runtime_status != RPM_ACTIVE) | |
389 | retval = -EAGAIN; | |
390 | ||
391 | /* | |
392 | * Any pending request other than an idle notification takes | |
393 | * precedence over us, except that the timer may be running. | |
394 | */ | |
395 | else if (dev->power.request_pending && | |
396 | dev->power.request > RPM_REQ_IDLE) | |
397 | retval = -EAGAIN; | |
398 | ||
399 | /* Act as though RPM_NOWAIT is always set. */ | |
400 | else if (dev->power.idle_notification) | |
401 | retval = -EINPROGRESS; | |
5e928f77 RW |
402 | if (retval) |
403 | goto out; | |
404 | ||
1bfee5bc AS |
405 | /* Pending requests need to be canceled. */ |
406 | dev->power.request = RPM_REQ_NONE; | |
407 | ||
45f0a85c | 408 | if (dev->power.no_callbacks) |
7490e442 | 409 | goto out; |
7490e442 | 410 | |
1bfee5bc AS |
411 | /* Carry out an asynchronous or a synchronous idle notification. */ |
412 | if (rpmflags & RPM_ASYNC) { | |
413 | dev->power.request = RPM_REQ_IDLE; | |
414 | if (!dev->power.request_pending) { | |
415 | dev->power.request_pending = true; | |
416 | queue_work(pm_wq, &dev->power.work); | |
5e928f77 | 417 | } |
d7737ce9 | 418 | trace_rpm_return_int_rcuidle(dev, _THIS_IP_, 0); |
45f0a85c | 419 | return 0; |
5e928f77 RW |
420 | } |
421 | ||
422 | dev->power.idle_notification = true; | |
423 | ||
dbcd2d72 | 424 | callback = RPM_GET_CALLBACK(dev, runtime_idle); |
35cd133c | 425 | |
ad3c36a5 | 426 | if (callback) |
45f0a85c | 427 | retval = __rpm_callback(callback, dev); |
5e928f77 RW |
428 | |
429 | dev->power.idle_notification = false; | |
430 | wake_up_all(&dev->power.wait_queue); | |
431 | ||
432 | out: | |
d7737ce9 | 433 | trace_rpm_return_int_rcuidle(dev, _THIS_IP_, retval); |
d66e6db2 | 434 | return retval ? retval : rpm_suspend(dev, rpmflags | RPM_AUTO); |
5e928f77 RW |
435 | } |
436 | ||
71c63122 RW |
437 | /** |
438 | * rpm_callback - Run a given runtime PM callback for a given device. | |
439 | * @cb: Runtime PM callback to run. | |
440 | * @dev: Device to run the callback for. | |
441 | */ | |
442 | static int rpm_callback(int (*cb)(struct device *), struct device *dev) | |
71c63122 RW |
443 | { |
444 | int retval; | |
445 | ||
446 | if (!cb) | |
447 | return -ENOSYS; | |
448 | ||
db88175f ML |
449 | if (dev->power.memalloc_noio) { |
450 | unsigned int noio_flag; | |
451 | ||
452 | /* | |
453 | * Deadlock might be caused if memory allocation with | |
454 | * GFP_KERNEL happens inside runtime_suspend and | |
455 | * runtime_resume callbacks of one block device's | |
456 | * ancestor or the block device itself. Network | |
457 | * device might be thought as part of iSCSI block | |
458 | * device, so network device and its ancestor should | |
459 | * be marked as memalloc_noio too. | |
460 | */ | |
461 | noio_flag = memalloc_noio_save(); | |
462 | retval = __rpm_callback(cb, dev); | |
463 | memalloc_noio_restore(noio_flag); | |
464 | } else { | |
465 | retval = __rpm_callback(cb, dev); | |
466 | } | |
71c63122 | 467 | |
71c63122 | 468 | dev->power.runtime_error = retval; |
632e270e | 469 | return retval != -EACCES ? retval : -EIO; |
71c63122 RW |
470 | } |
471 | ||
5e928f77 | 472 | /** |
62052ab1 | 473 | * rpm_suspend - Carry out runtime suspend of given device. |
5e928f77 | 474 | * @dev: Device to suspend. |
3f9af051 | 475 | * @rpmflags: Flag bits. |
5e928f77 | 476 | * |
47d8f0ba ML |
477 | * Check if the device's runtime PM status allows it to be suspended. |
478 | * Cancel a pending idle notification, autosuspend or suspend. If | |
479 | * another suspend has been started earlier, either return immediately | |
480 | * or wait for it to finish, depending on the RPM_NOWAIT and RPM_ASYNC | |
481 | * flags. If the RPM_ASYNC flag is set then queue a suspend request; | |
857b36c7 ML |
482 | * otherwise run the ->runtime_suspend() callback directly. When |
483 | * ->runtime_suspend succeeded, if a deferred resume was requested while | |
484 | * the callback was running then carry it out, otherwise send an idle | |
485 | * notification for its parent (if the suspend succeeded and both | |
486 | * ignore_children of parent->power and irq_safe of dev->power are not set). | |
886486b7 AS |
487 | * If ->runtime_suspend failed with -EAGAIN or -EBUSY, and if the RPM_AUTO |
488 | * flag is set and the next autosuspend-delay expiration time is in the | |
489 | * future, schedule another autosuspend attempt. | |
5e928f77 RW |
490 | * |
491 | * This function must be called under dev->power.lock with interrupts disabled. | |
492 | */ | |
140a6c94 | 493 | static int rpm_suspend(struct device *dev, int rpmflags) |
5e928f77 RW |
494 | __releases(&dev->power.lock) __acquires(&dev->power.lock) |
495 | { | |
71c63122 | 496 | int (*callback)(struct device *); |
5e928f77 | 497 | struct device *parent = NULL; |
1bfee5bc | 498 | int retval; |
5e928f77 | 499 | |
77893577 | 500 | trace_rpm_suspend_rcuidle(dev, rpmflags); |
5e928f77 RW |
501 | |
502 | repeat: | |
1bfee5bc | 503 | retval = rpm_check_suspend_allowed(dev); |
5e928f77 | 504 | |
1bfee5bc AS |
505 | if (retval < 0) |
506 | ; /* Conditions are wrong. */ | |
507 | ||
508 | /* Synchronous suspends are not allowed in the RPM_RESUMING state. */ | |
509 | else if (dev->power.runtime_status == RPM_RESUMING && | |
510 | !(rpmflags & RPM_ASYNC)) | |
5e928f77 | 511 | retval = -EAGAIN; |
1bfee5bc | 512 | if (retval) |
5e928f77 | 513 | goto out; |
5e928f77 | 514 | |
15bcb91d AS |
515 | /* If the autosuspend_delay time hasn't expired yet, reschedule. */ |
516 | if ((rpmflags & RPM_AUTO) | |
517 | && dev->power.runtime_status != RPM_SUSPENDING) { | |
518 | unsigned long expires = pm_runtime_autosuspend_expiration(dev); | |
519 | ||
520 | if (expires != 0) { | |
521 | /* Pending requests need to be canceled. */ | |
522 | dev->power.request = RPM_REQ_NONE; | |
523 | ||
524 | /* | |
525 | * Optimization: If the timer is already running and is | |
526 | * set to expire at or before the autosuspend delay, | |
527 | * avoid the overhead of resetting it. Just let it | |
528 | * expire; pm_suspend_timer_fn() will take care of the | |
529 | * rest. | |
530 | */ | |
531 | if (!(dev->power.timer_expires && time_before_eq( | |
532 | dev->power.timer_expires, expires))) { | |
533 | dev->power.timer_expires = expires; | |
534 | mod_timer(&dev->power.suspend_timer, expires); | |
535 | } | |
536 | dev->power.timer_autosuspends = 1; | |
537 | goto out; | |
538 | } | |
539 | } | |
540 | ||
5e928f77 RW |
541 | /* Other scheduled or pending requests need to be canceled. */ |
542 | pm_runtime_cancel_pending(dev); | |
543 | ||
5e928f77 RW |
544 | if (dev->power.runtime_status == RPM_SUSPENDING) { |
545 | DEFINE_WAIT(wait); | |
546 | ||
1bfee5bc | 547 | if (rpmflags & (RPM_ASYNC | RPM_NOWAIT)) { |
5e928f77 RW |
548 | retval = -EINPROGRESS; |
549 | goto out; | |
550 | } | |
551 | ||
ad3c36a5 RW |
552 | if (dev->power.irq_safe) { |
553 | spin_unlock(&dev->power.lock); | |
554 | ||
555 | cpu_relax(); | |
556 | ||
557 | spin_lock(&dev->power.lock); | |
558 | goto repeat; | |
559 | } | |
560 | ||
5e928f77 RW |
561 | /* Wait for the other suspend running in parallel with us. */ |
562 | for (;;) { | |
563 | prepare_to_wait(&dev->power.wait_queue, &wait, | |
564 | TASK_UNINTERRUPTIBLE); | |
565 | if (dev->power.runtime_status != RPM_SUSPENDING) | |
566 | break; | |
567 | ||
568 | spin_unlock_irq(&dev->power.lock); | |
569 | ||
570 | schedule(); | |
571 | ||
572 | spin_lock_irq(&dev->power.lock); | |
573 | } | |
574 | finish_wait(&dev->power.wait_queue, &wait); | |
575 | goto repeat; | |
576 | } | |
577 | ||
7490e442 AS |
578 | if (dev->power.no_callbacks) |
579 | goto no_callback; /* Assume success. */ | |
580 | ||
1bfee5bc AS |
581 | /* Carry out an asynchronous or a synchronous suspend. */ |
582 | if (rpmflags & RPM_ASYNC) { | |
15bcb91d AS |
583 | dev->power.request = (rpmflags & RPM_AUTO) ? |
584 | RPM_REQ_AUTOSUSPEND : RPM_REQ_SUSPEND; | |
1bfee5bc AS |
585 | if (!dev->power.request_pending) { |
586 | dev->power.request_pending = true; | |
587 | queue_work(pm_wq, &dev->power.work); | |
588 | } | |
589 | goto out; | |
590 | } | |
591 | ||
8d4b9d1b | 592 | __update_runtime_status(dev, RPM_SUSPENDING); |
5e928f77 | 593 | |
dbcd2d72 | 594 | callback = RPM_GET_CALLBACK(dev, runtime_suspend); |
35cd133c | 595 | |
bed57030 | 596 | dev_pm_enable_wake_irq_check(dev, true); |
71c63122 | 597 | retval = rpm_callback(callback, dev); |
00dc9ad1 RW |
598 | if (retval) |
599 | goto fail; | |
886486b7 | 600 | |
7490e442 | 601 | no_callback: |
857b36c7 ML |
602 | __update_runtime_status(dev, RPM_SUSPENDED); |
603 | pm_runtime_deactivate_timer(dev); | |
5e928f77 | 604 | |
857b36c7 ML |
605 | if (dev->parent) { |
606 | parent = dev->parent; | |
607 | atomic_add_unless(&parent->power.child_count, -1, 0); | |
5e928f77 RW |
608 | } |
609 | wake_up_all(&dev->power.wait_queue); | |
610 | ||
611 | if (dev->power.deferred_resume) { | |
58a34de7 | 612 | dev->power.deferred_resume = false; |
140a6c94 | 613 | rpm_resume(dev, 0); |
5e928f77 RW |
614 | retval = -EAGAIN; |
615 | goto out; | |
616 | } | |
617 | ||
c3810c88 | 618 | /* Maybe the parent is now able to suspend. */ |
c7b61de5 | 619 | if (parent && !parent->power.ignore_children && !dev->power.irq_safe) { |
c3810c88 | 620 | spin_unlock(&dev->power.lock); |
5e928f77 | 621 | |
c3810c88 AS |
622 | spin_lock(&parent->power.lock); |
623 | rpm_idle(parent, RPM_ASYNC); | |
624 | spin_unlock(&parent->power.lock); | |
5e928f77 | 625 | |
c3810c88 | 626 | spin_lock(&dev->power.lock); |
5e928f77 RW |
627 | } |
628 | ||
629 | out: | |
77893577 | 630 | trace_rpm_return_int_rcuidle(dev, _THIS_IP_, retval); |
5e928f77 RW |
631 | |
632 | return retval; | |
00dc9ad1 RW |
633 | |
634 | fail: | |
bed57030 | 635 | dev_pm_disable_wake_irq_check(dev); |
00dc9ad1 | 636 | __update_runtime_status(dev, RPM_ACTIVE); |
00dc9ad1 | 637 | dev->power.deferred_resume = false; |
f2791d73 AS |
638 | wake_up_all(&dev->power.wait_queue); |
639 | ||
00dc9ad1 RW |
640 | if (retval == -EAGAIN || retval == -EBUSY) { |
641 | dev->power.runtime_error = 0; | |
642 | ||
643 | /* | |
644 | * If the callback routine failed an autosuspend, and | |
645 | * if the last_busy time has been updated so that there | |
646 | * is a new autosuspend expiration time, automatically | |
647 | * reschedule another autosuspend. | |
648 | */ | |
649 | if ((rpmflags & RPM_AUTO) && | |
650 | pm_runtime_autosuspend_expiration(dev) != 0) | |
651 | goto repeat; | |
652 | } else { | |
653 | pm_runtime_cancel_pending(dev); | |
654 | } | |
00dc9ad1 | 655 | goto out; |
5e928f77 RW |
656 | } |
657 | ||
658 | /** | |
62052ab1 | 659 | * rpm_resume - Carry out runtime resume of given device. |
5e928f77 | 660 | * @dev: Device to resume. |
3f9af051 | 661 | * @rpmflags: Flag bits. |
5e928f77 | 662 | * |
62052ab1 | 663 | * Check if the device's runtime PM status allows it to be resumed. Cancel |
1bfee5bc | 664 | * any scheduled or pending requests. If another resume has been started |
25985edc | 665 | * earlier, either return immediately or wait for it to finish, depending on the |
1bfee5bc AS |
666 | * RPM_NOWAIT and RPM_ASYNC flags. Similarly, if there's a suspend running in |
667 | * parallel with this function, either tell the other process to resume after | |
668 | * suspending (deferred_resume) or wait for it to finish. If the RPM_ASYNC | |
669 | * flag is set then queue a resume request; otherwise run the | |
670 | * ->runtime_resume() callback directly. Queue an idle notification for the | |
671 | * device if the resume succeeded. | |
5e928f77 RW |
672 | * |
673 | * This function must be called under dev->power.lock with interrupts disabled. | |
674 | */ | |
140a6c94 | 675 | static int rpm_resume(struct device *dev, int rpmflags) |
5e928f77 RW |
676 | __releases(&dev->power.lock) __acquires(&dev->power.lock) |
677 | { | |
71c63122 | 678 | int (*callback)(struct device *); |
5e928f77 RW |
679 | struct device *parent = NULL; |
680 | int retval = 0; | |
681 | ||
d44c950e | 682 | trace_rpm_resume_rcuidle(dev, rpmflags); |
5e928f77 RW |
683 | |
684 | repeat: | |
1bfee5bc | 685 | if (dev->power.runtime_error) |
5e928f77 | 686 | retval = -EINVAL; |
6f3c77b0 KH |
687 | else if (dev->power.disable_depth == 1 && dev->power.is_suspended |
688 | && dev->power.runtime_status == RPM_ACTIVE) | |
689 | retval = 1; | |
1bfee5bc | 690 | else if (dev->power.disable_depth > 0) |
632e270e | 691 | retval = -EACCES; |
1bfee5bc | 692 | if (retval) |
5e928f77 | 693 | goto out; |
5e928f77 | 694 | |
15bcb91d AS |
695 | /* |
696 | * Other scheduled or pending requests need to be canceled. Small | |
697 | * optimization: If an autosuspend timer is running, leave it running | |
698 | * rather than cancelling it now only to restart it again in the near | |
699 | * future. | |
700 | */ | |
701 | dev->power.request = RPM_REQ_NONE; | |
702 | if (!dev->power.timer_autosuspends) | |
703 | pm_runtime_deactivate_timer(dev); | |
5e928f77 | 704 | |
1bfee5bc | 705 | if (dev->power.runtime_status == RPM_ACTIVE) { |
5e928f77 | 706 | retval = 1; |
5e928f77 | 707 | goto out; |
1bfee5bc | 708 | } |
5e928f77 RW |
709 | |
710 | if (dev->power.runtime_status == RPM_RESUMING | |
711 | || dev->power.runtime_status == RPM_SUSPENDING) { | |
712 | DEFINE_WAIT(wait); | |
713 | ||
1bfee5bc | 714 | if (rpmflags & (RPM_ASYNC | RPM_NOWAIT)) { |
5e928f77 RW |
715 | if (dev->power.runtime_status == RPM_SUSPENDING) |
716 | dev->power.deferred_resume = true; | |
1bfee5bc AS |
717 | else |
718 | retval = -EINPROGRESS; | |
5e928f77 RW |
719 | goto out; |
720 | } | |
721 | ||
ad3c36a5 RW |
722 | if (dev->power.irq_safe) { |
723 | spin_unlock(&dev->power.lock); | |
724 | ||
725 | cpu_relax(); | |
726 | ||
727 | spin_lock(&dev->power.lock); | |
728 | goto repeat; | |
729 | } | |
730 | ||
5e928f77 RW |
731 | /* Wait for the operation carried out in parallel with us. */ |
732 | for (;;) { | |
733 | prepare_to_wait(&dev->power.wait_queue, &wait, | |
734 | TASK_UNINTERRUPTIBLE); | |
735 | if (dev->power.runtime_status != RPM_RESUMING | |
736 | && dev->power.runtime_status != RPM_SUSPENDING) | |
737 | break; | |
738 | ||
739 | spin_unlock_irq(&dev->power.lock); | |
740 | ||
741 | schedule(); | |
742 | ||
743 | spin_lock_irq(&dev->power.lock); | |
744 | } | |
745 | finish_wait(&dev->power.wait_queue, &wait); | |
746 | goto repeat; | |
747 | } | |
748 | ||
7490e442 AS |
749 | /* |
750 | * See if we can skip waking up the parent. This is safe only if | |
751 | * power.no_callbacks is set, because otherwise we don't know whether | |
752 | * the resume will actually succeed. | |
753 | */ | |
754 | if (dev->power.no_callbacks && !parent && dev->parent) { | |
d63be5f9 | 755 | spin_lock_nested(&dev->parent->power.lock, SINGLE_DEPTH_NESTING); |
7490e442 AS |
756 | if (dev->parent->power.disable_depth > 0 |
757 | || dev->parent->power.ignore_children | |
758 | || dev->parent->power.runtime_status == RPM_ACTIVE) { | |
759 | atomic_inc(&dev->parent->power.child_count); | |
760 | spin_unlock(&dev->parent->power.lock); | |
7f321c26 | 761 | retval = 1; |
7490e442 AS |
762 | goto no_callback; /* Assume success. */ |
763 | } | |
764 | spin_unlock(&dev->parent->power.lock); | |
765 | } | |
766 | ||
1bfee5bc AS |
767 | /* Carry out an asynchronous or a synchronous resume. */ |
768 | if (rpmflags & RPM_ASYNC) { | |
769 | dev->power.request = RPM_REQ_RESUME; | |
770 | if (!dev->power.request_pending) { | |
771 | dev->power.request_pending = true; | |
772 | queue_work(pm_wq, &dev->power.work); | |
773 | } | |
774 | retval = 0; | |
775 | goto out; | |
776 | } | |
777 | ||
5e928f77 RW |
778 | if (!parent && dev->parent) { |
779 | /* | |
c7b61de5 AS |
780 | * Increment the parent's usage counter and resume it if |
781 | * necessary. Not needed if dev is irq-safe; then the | |
782 | * parent is permanently resumed. | |
5e928f77 RW |
783 | */ |
784 | parent = dev->parent; | |
c7b61de5 AS |
785 | if (dev->power.irq_safe) |
786 | goto skip_parent; | |
862f89b3 | 787 | spin_unlock(&dev->power.lock); |
5e928f77 RW |
788 | |
789 | pm_runtime_get_noresume(parent); | |
790 | ||
862f89b3 | 791 | spin_lock(&parent->power.lock); |
5e928f77 | 792 | /* |
216ef0b6 UH |
793 | * Resume the parent if it has runtime PM enabled and not been |
794 | * set to ignore its children. | |
5e928f77 RW |
795 | */ |
796 | if (!parent->power.disable_depth | |
797 | && !parent->power.ignore_children) { | |
140a6c94 | 798 | rpm_resume(parent, 0); |
5e928f77 RW |
799 | if (parent->power.runtime_status != RPM_ACTIVE) |
800 | retval = -EBUSY; | |
801 | } | |
862f89b3 | 802 | spin_unlock(&parent->power.lock); |
5e928f77 | 803 | |
862f89b3 | 804 | spin_lock(&dev->power.lock); |
5e928f77 RW |
805 | if (retval) |
806 | goto out; | |
807 | goto repeat; | |
808 | } | |
c7b61de5 | 809 | skip_parent: |
5e928f77 | 810 | |
7490e442 AS |
811 | if (dev->power.no_callbacks) |
812 | goto no_callback; /* Assume success. */ | |
813 | ||
8d4b9d1b | 814 | __update_runtime_status(dev, RPM_RESUMING); |
5e928f77 | 815 | |
dbcd2d72 | 816 | callback = RPM_GET_CALLBACK(dev, runtime_resume); |
35cd133c | 817 | |
bed57030 | 818 | dev_pm_disable_wake_irq_check(dev); |
71c63122 | 819 | retval = rpm_callback(callback, dev); |
5e928f77 | 820 | if (retval) { |
8d4b9d1b | 821 | __update_runtime_status(dev, RPM_SUSPENDED); |
5e928f77 | 822 | pm_runtime_cancel_pending(dev); |
bed57030 | 823 | dev_pm_enable_wake_irq_check(dev, false); |
5e928f77 | 824 | } else { |
7490e442 | 825 | no_callback: |
8d4b9d1b | 826 | __update_runtime_status(dev, RPM_ACTIVE); |
56f487c7 | 827 | pm_runtime_mark_last_busy(dev); |
5e928f77 RW |
828 | if (parent) |
829 | atomic_inc(&parent->power.child_count); | |
830 | } | |
831 | wake_up_all(&dev->power.wait_queue); | |
832 | ||
7f321c26 | 833 | if (retval >= 0) |
140a6c94 | 834 | rpm_idle(dev, RPM_ASYNC); |
5e928f77 RW |
835 | |
836 | out: | |
c7b61de5 | 837 | if (parent && !dev->power.irq_safe) { |
5e928f77 RW |
838 | spin_unlock_irq(&dev->power.lock); |
839 | ||
840 | pm_runtime_put(parent); | |
841 | ||
842 | spin_lock_irq(&dev->power.lock); | |
843 | } | |
844 | ||
d44c950e | 845 | trace_rpm_return_int_rcuidle(dev, _THIS_IP_, retval); |
5e928f77 RW |
846 | |
847 | return retval; | |
848 | } | |
849 | ||
5e928f77 | 850 | /** |
62052ab1 | 851 | * pm_runtime_work - Universal runtime PM work function. |
5e928f77 RW |
852 | * @work: Work structure used for scheduling the execution of this function. |
853 | * | |
854 | * Use @work to get the device object the work is to be done for, determine what | |
62052ab1 | 855 | * is to be done and execute the appropriate runtime PM function. |
5e928f77 RW |
856 | */ |
857 | static void pm_runtime_work(struct work_struct *work) | |
858 | { | |
859 | struct device *dev = container_of(work, struct device, power.work); | |
860 | enum rpm_request req; | |
861 | ||
862 | spin_lock_irq(&dev->power.lock); | |
863 | ||
864 | if (!dev->power.request_pending) | |
865 | goto out; | |
866 | ||
867 | req = dev->power.request; | |
868 | dev->power.request = RPM_REQ_NONE; | |
869 | dev->power.request_pending = false; | |
870 | ||
871 | switch (req) { | |
872 | case RPM_REQ_NONE: | |
873 | break; | |
874 | case RPM_REQ_IDLE: | |
140a6c94 | 875 | rpm_idle(dev, RPM_NOWAIT); |
5e928f77 RW |
876 | break; |
877 | case RPM_REQ_SUSPEND: | |
140a6c94 | 878 | rpm_suspend(dev, RPM_NOWAIT); |
5e928f77 | 879 | break; |
15bcb91d AS |
880 | case RPM_REQ_AUTOSUSPEND: |
881 | rpm_suspend(dev, RPM_NOWAIT | RPM_AUTO); | |
882 | break; | |
5e928f77 | 883 | case RPM_REQ_RESUME: |
140a6c94 | 884 | rpm_resume(dev, RPM_NOWAIT); |
5e928f77 RW |
885 | break; |
886 | } | |
887 | ||
888 | out: | |
889 | spin_unlock_irq(&dev->power.lock); | |
890 | } | |
891 | ||
5e928f77 RW |
892 | /** |
893 | * pm_suspend_timer_fn - Timer function for pm_schedule_suspend(). | |
894 | * @data: Device pointer passed by pm_schedule_suspend(). | |
895 | * | |
1bfee5bc | 896 | * Check if the time is right and queue a suspend request. |
5e928f77 | 897 | */ |
96428e98 | 898 | static void pm_suspend_timer_fn(struct timer_list *t) |
5e928f77 | 899 | { |
96428e98 | 900 | struct device *dev = from_timer(dev, t, power.suspend_timer); |
5e928f77 RW |
901 | unsigned long flags; |
902 | unsigned long expires; | |
903 | ||
904 | spin_lock_irqsave(&dev->power.lock, flags); | |
905 | ||
906 | expires = dev->power.timer_expires; | |
907 | /* If 'expire' is after 'jiffies' we've been called too early. */ | |
908 | if (expires > 0 && !time_after(expires, jiffies)) { | |
909 | dev->power.timer_expires = 0; | |
15bcb91d AS |
910 | rpm_suspend(dev, dev->power.timer_autosuspends ? |
911 | (RPM_ASYNC | RPM_AUTO) : RPM_ASYNC); | |
5e928f77 RW |
912 | } |
913 | ||
914 | spin_unlock_irqrestore(&dev->power.lock, flags); | |
915 | } | |
916 | ||
917 | /** | |
918 | * pm_schedule_suspend - Set up a timer to submit a suspend request in future. | |
919 | * @dev: Device to suspend. | |
920 | * @delay: Time to wait before submitting a suspend request, in milliseconds. | |
921 | */ | |
922 | int pm_schedule_suspend(struct device *dev, unsigned int delay) | |
923 | { | |
924 | unsigned long flags; | |
1bfee5bc | 925 | int retval; |
5e928f77 RW |
926 | |
927 | spin_lock_irqsave(&dev->power.lock, flags); | |
928 | ||
5e928f77 | 929 | if (!delay) { |
140a6c94 | 930 | retval = rpm_suspend(dev, RPM_ASYNC); |
5e928f77 RW |
931 | goto out; |
932 | } | |
933 | ||
1bfee5bc | 934 | retval = rpm_check_suspend_allowed(dev); |
5e928f77 RW |
935 | if (retval) |
936 | goto out; | |
937 | ||
1bfee5bc AS |
938 | /* Other scheduled or pending requests need to be canceled. */ |
939 | pm_runtime_cancel_pending(dev); | |
940 | ||
5e928f77 | 941 | dev->power.timer_expires = jiffies + msecs_to_jiffies(delay); |
1bfee5bc | 942 | dev->power.timer_expires += !dev->power.timer_expires; |
15bcb91d | 943 | dev->power.timer_autosuspends = 0; |
5e928f77 RW |
944 | mod_timer(&dev->power.suspend_timer, dev->power.timer_expires); |
945 | ||
946 | out: | |
947 | spin_unlock_irqrestore(&dev->power.lock, flags); | |
948 | ||
949 | return retval; | |
950 | } | |
951 | EXPORT_SYMBOL_GPL(pm_schedule_suspend); | |
952 | ||
5e928f77 | 953 | /** |
62052ab1 | 954 | * __pm_runtime_idle - Entry point for runtime idle operations. |
140a6c94 AS |
955 | * @dev: Device to send idle notification for. |
956 | * @rpmflags: Flag bits. | |
957 | * | |
958 | * If the RPM_GET_PUT flag is set, decrement the device's usage count and | |
959 | * return immediately if it is larger than zero. Then carry out an idle | |
960 | * notification, either synchronous or asynchronous. | |
961 | * | |
311aab73 CC |
962 | * This routine may be called in atomic context if the RPM_ASYNC flag is set, |
963 | * or if pm_runtime_irq_safe() has been called. | |
5e928f77 | 964 | */ |
140a6c94 | 965 | int __pm_runtime_idle(struct device *dev, int rpmflags) |
5e928f77 RW |
966 | { |
967 | unsigned long flags; | |
968 | int retval; | |
969 | ||
140a6c94 AS |
970 | if (rpmflags & RPM_GET_PUT) { |
971 | if (!atomic_dec_and_test(&dev->power.usage_count)) | |
972 | return 0; | |
973 | } | |
974 | ||
a9306a63 RW |
975 | might_sleep_if(!(rpmflags & RPM_ASYNC) && !dev->power.irq_safe); |
976 | ||
5e928f77 | 977 | spin_lock_irqsave(&dev->power.lock, flags); |
140a6c94 | 978 | retval = rpm_idle(dev, rpmflags); |
5e928f77 RW |
979 | spin_unlock_irqrestore(&dev->power.lock, flags); |
980 | ||
981 | return retval; | |
982 | } | |
140a6c94 | 983 | EXPORT_SYMBOL_GPL(__pm_runtime_idle); |
5e928f77 RW |
984 | |
985 | /** | |
62052ab1 | 986 | * __pm_runtime_suspend - Entry point for runtime put/suspend operations. |
140a6c94 | 987 | * @dev: Device to suspend. |
3f9af051 | 988 | * @rpmflags: Flag bits. |
5e928f77 | 989 | * |
15bcb91d AS |
990 | * If the RPM_GET_PUT flag is set, decrement the device's usage count and |
991 | * return immediately if it is larger than zero. Then carry out a suspend, | |
992 | * either synchronous or asynchronous. | |
140a6c94 | 993 | * |
311aab73 CC |
994 | * This routine may be called in atomic context if the RPM_ASYNC flag is set, |
995 | * or if pm_runtime_irq_safe() has been called. | |
5e928f77 | 996 | */ |
140a6c94 | 997 | int __pm_runtime_suspend(struct device *dev, int rpmflags) |
5e928f77 | 998 | { |
140a6c94 | 999 | unsigned long flags; |
1d531c14 | 1000 | int retval; |
5e928f77 | 1001 | |
15bcb91d AS |
1002 | if (rpmflags & RPM_GET_PUT) { |
1003 | if (!atomic_dec_and_test(&dev->power.usage_count)) | |
1004 | return 0; | |
1005 | } | |
1006 | ||
a9306a63 RW |
1007 | might_sleep_if(!(rpmflags & RPM_ASYNC) && !dev->power.irq_safe); |
1008 | ||
140a6c94 AS |
1009 | spin_lock_irqsave(&dev->power.lock, flags); |
1010 | retval = rpm_suspend(dev, rpmflags); | |
1011 | spin_unlock_irqrestore(&dev->power.lock, flags); | |
5e928f77 RW |
1012 | |
1013 | return retval; | |
1014 | } | |
140a6c94 | 1015 | EXPORT_SYMBOL_GPL(__pm_runtime_suspend); |
5e928f77 RW |
1016 | |
1017 | /** | |
62052ab1 | 1018 | * __pm_runtime_resume - Entry point for runtime resume operations. |
140a6c94 | 1019 | * @dev: Device to resume. |
3f9af051 | 1020 | * @rpmflags: Flag bits. |
5e928f77 | 1021 | * |
140a6c94 AS |
1022 | * If the RPM_GET_PUT flag is set, increment the device's usage count. Then |
1023 | * carry out a resume, either synchronous or asynchronous. | |
1024 | * | |
311aab73 CC |
1025 | * This routine may be called in atomic context if the RPM_ASYNC flag is set, |
1026 | * or if pm_runtime_irq_safe() has been called. | |
5e928f77 | 1027 | */ |
140a6c94 | 1028 | int __pm_runtime_resume(struct device *dev, int rpmflags) |
5e928f77 | 1029 | { |
140a6c94 AS |
1030 | unsigned long flags; |
1031 | int retval; | |
5e928f77 | 1032 | |
a9306a63 RW |
1033 | might_sleep_if(!(rpmflags & RPM_ASYNC) && !dev->power.irq_safe && |
1034 | dev->power.runtime_status != RPM_ACTIVE); | |
311aab73 | 1035 | |
140a6c94 AS |
1036 | if (rpmflags & RPM_GET_PUT) |
1037 | atomic_inc(&dev->power.usage_count); | |
1038 | ||
1039 | spin_lock_irqsave(&dev->power.lock, flags); | |
1040 | retval = rpm_resume(dev, rpmflags); | |
1041 | spin_unlock_irqrestore(&dev->power.lock, flags); | |
5e928f77 RW |
1042 | |
1043 | return retval; | |
1044 | } | |
140a6c94 | 1045 | EXPORT_SYMBOL_GPL(__pm_runtime_resume); |
5e928f77 | 1046 | |
a436b6a1 RW |
1047 | /** |
1048 | * pm_runtime_get_if_in_use - Conditionally bump up the device's usage counter. | |
1049 | * @dev: Device to handle. | |
1050 | * | |
1051 | * Return -EINVAL if runtime PM is disabled for the device. | |
1052 | * | |
1053 | * If that's not the case and if the device's runtime PM status is RPM_ACTIVE | |
1054 | * and the runtime PM usage counter is nonzero, increment the counter and | |
1055 | * return 1. Otherwise return 0 without changing the counter. | |
1056 | */ | |
1057 | int pm_runtime_get_if_in_use(struct device *dev) | |
1058 | { | |
1059 | unsigned long flags; | |
1060 | int retval; | |
1061 | ||
1062 | spin_lock_irqsave(&dev->power.lock, flags); | |
1063 | retval = dev->power.disable_depth > 0 ? -EINVAL : | |
1064 | dev->power.runtime_status == RPM_ACTIVE | |
1065 | && atomic_inc_not_zero(&dev->power.usage_count); | |
1066 | spin_unlock_irqrestore(&dev->power.lock, flags); | |
1067 | return retval; | |
1068 | } | |
1069 | EXPORT_SYMBOL_GPL(pm_runtime_get_if_in_use); | |
1070 | ||
5e928f77 | 1071 | /** |
62052ab1 | 1072 | * __pm_runtime_set_status - Set runtime PM status of a device. |
5e928f77 | 1073 | * @dev: Device to handle. |
62052ab1 | 1074 | * @status: New runtime PM status of the device. |
5e928f77 | 1075 | * |
62052ab1 | 1076 | * If runtime PM of the device is disabled or its power.runtime_error field is |
5e928f77 RW |
1077 | * different from zero, the status may be changed either to RPM_ACTIVE, or to |
1078 | * RPM_SUSPENDED, as long as that reflects the actual state of the device. | |
1079 | * However, if the device has a parent and the parent is not active, and the | |
1080 | * parent's power.ignore_children flag is unset, the device's status cannot be | |
1081 | * set to RPM_ACTIVE, so -EBUSY is returned in that case. | |
1082 | * | |
1083 | * If successful, __pm_runtime_set_status() clears the power.runtime_error field | |
1084 | * and the device parent's counter of unsuspended children is modified to | |
1085 | * reflect the new status. If the new status is RPM_SUSPENDED, an idle | |
1086 | * notification request for the parent is submitted. | |
1087 | */ | |
1088 | int __pm_runtime_set_status(struct device *dev, unsigned int status) | |
1089 | { | |
1090 | struct device *parent = dev->parent; | |
1091 | unsigned long flags; | |
1092 | bool notify_parent = false; | |
1093 | int error = 0; | |
1094 | ||
1095 | if (status != RPM_ACTIVE && status != RPM_SUSPENDED) | |
1096 | return -EINVAL; | |
1097 | ||
1098 | spin_lock_irqsave(&dev->power.lock, flags); | |
1099 | ||
1100 | if (!dev->power.runtime_error && !dev->power.disable_depth) { | |
1101 | error = -EAGAIN; | |
1102 | goto out; | |
1103 | } | |
1104 | ||
f8817f61 | 1105 | if (dev->power.runtime_status == status || !parent) |
5e928f77 RW |
1106 | goto out_set; |
1107 | ||
1108 | if (status == RPM_SUSPENDED) { | |
f8817f61 RW |
1109 | atomic_add_unless(&parent->power.child_count, -1, 0); |
1110 | notify_parent = !parent->power.ignore_children; | |
1111 | } else { | |
bab636b9 | 1112 | spin_lock_nested(&parent->power.lock, SINGLE_DEPTH_NESTING); |
5e928f77 RW |
1113 | |
1114 | /* | |
1115 | * It is invalid to put an active child under a parent that is | |
62052ab1 | 1116 | * not active, has runtime PM enabled and the |
5e928f77 RW |
1117 | * 'power.ignore_children' flag unset. |
1118 | */ | |
1119 | if (!parent->power.disable_depth | |
1120 | && !parent->power.ignore_children | |
71723f95 LW |
1121 | && parent->power.runtime_status != RPM_ACTIVE) { |
1122 | dev_err(dev, "runtime PM trying to activate child device %s but parent (%s) is not active\n", | |
1123 | dev_name(dev), | |
1124 | dev_name(parent)); | |
5e928f77 | 1125 | error = -EBUSY; |
71723f95 | 1126 | } else if (dev->power.runtime_status == RPM_SUSPENDED) { |
965c4ac0 | 1127 | atomic_inc(&parent->power.child_count); |
71723f95 | 1128 | } |
5e928f77 | 1129 | |
862f89b3 | 1130 | spin_unlock(&parent->power.lock); |
5e928f77 RW |
1131 | |
1132 | if (error) | |
1133 | goto out; | |
1134 | } | |
1135 | ||
1136 | out_set: | |
8d4b9d1b | 1137 | __update_runtime_status(dev, status); |
5e928f77 RW |
1138 | dev->power.runtime_error = 0; |
1139 | out: | |
1140 | spin_unlock_irqrestore(&dev->power.lock, flags); | |
1141 | ||
1142 | if (notify_parent) | |
1143 | pm_request_idle(parent); | |
1144 | ||
1145 | return error; | |
1146 | } | |
1147 | EXPORT_SYMBOL_GPL(__pm_runtime_set_status); | |
1148 | ||
1149 | /** | |
1150 | * __pm_runtime_barrier - Cancel pending requests and wait for completions. | |
1151 | * @dev: Device to handle. | |
1152 | * | |
1153 | * Flush all pending requests for the device from pm_wq and wait for all | |
62052ab1 | 1154 | * runtime PM operations involving the device in progress to complete. |
5e928f77 RW |
1155 | * |
1156 | * Should be called under dev->power.lock with interrupts disabled. | |
1157 | */ | |
1158 | static void __pm_runtime_barrier(struct device *dev) | |
1159 | { | |
1160 | pm_runtime_deactivate_timer(dev); | |
1161 | ||
1162 | if (dev->power.request_pending) { | |
1163 | dev->power.request = RPM_REQ_NONE; | |
1164 | spin_unlock_irq(&dev->power.lock); | |
1165 | ||
1166 | cancel_work_sync(&dev->power.work); | |
1167 | ||
1168 | spin_lock_irq(&dev->power.lock); | |
1169 | dev->power.request_pending = false; | |
1170 | } | |
1171 | ||
1172 | if (dev->power.runtime_status == RPM_SUSPENDING | |
1173 | || dev->power.runtime_status == RPM_RESUMING | |
1174 | || dev->power.idle_notification) { | |
1175 | DEFINE_WAIT(wait); | |
1176 | ||
1177 | /* Suspend, wake-up or idle notification in progress. */ | |
1178 | for (;;) { | |
1179 | prepare_to_wait(&dev->power.wait_queue, &wait, | |
1180 | TASK_UNINTERRUPTIBLE); | |
1181 | if (dev->power.runtime_status != RPM_SUSPENDING | |
1182 | && dev->power.runtime_status != RPM_RESUMING | |
1183 | && !dev->power.idle_notification) | |
1184 | break; | |
1185 | spin_unlock_irq(&dev->power.lock); | |
1186 | ||
1187 | schedule(); | |
1188 | ||
1189 | spin_lock_irq(&dev->power.lock); | |
1190 | } | |
1191 | finish_wait(&dev->power.wait_queue, &wait); | |
1192 | } | |
1193 | } | |
1194 | ||
1195 | /** | |
1196 | * pm_runtime_barrier - Flush pending requests and wait for completions. | |
1197 | * @dev: Device to handle. | |
1198 | * | |
1199 | * Prevent the device from being suspended by incrementing its usage counter and | |
1200 | * if there's a pending resume request for the device, wake the device up. | |
1201 | * Next, make sure that all pending requests for the device have been flushed | |
62052ab1 | 1202 | * from pm_wq and wait for all runtime PM operations involving the device in |
5e928f77 RW |
1203 | * progress to complete. |
1204 | * | |
1205 | * Return value: | |
1206 | * 1, if there was a resume request pending and the device had to be woken up, | |
1207 | * 0, otherwise | |
1208 | */ | |
1209 | int pm_runtime_barrier(struct device *dev) | |
1210 | { | |
1211 | int retval = 0; | |
1212 | ||
1213 | pm_runtime_get_noresume(dev); | |
1214 | spin_lock_irq(&dev->power.lock); | |
1215 | ||
1216 | if (dev->power.request_pending | |
1217 | && dev->power.request == RPM_REQ_RESUME) { | |
140a6c94 | 1218 | rpm_resume(dev, 0); |
5e928f77 RW |
1219 | retval = 1; |
1220 | } | |
1221 | ||
1222 | __pm_runtime_barrier(dev); | |
1223 | ||
1224 | spin_unlock_irq(&dev->power.lock); | |
1225 | pm_runtime_put_noidle(dev); | |
1226 | ||
1227 | return retval; | |
1228 | } | |
1229 | EXPORT_SYMBOL_GPL(pm_runtime_barrier); | |
1230 | ||
1231 | /** | |
62052ab1 | 1232 | * __pm_runtime_disable - Disable runtime PM of a device. |
5e928f77 RW |
1233 | * @dev: Device to handle. |
1234 | * @check_resume: If set, check if there's a resume request for the device. | |
1235 | * | |
7b60894f | 1236 | * Increment power.disable_depth for the device and if it was zero previously, |
62052ab1 | 1237 | * cancel all pending runtime PM requests for the device and wait for all |
5e928f77 | 1238 | * operations in progress to complete. The device can be either active or |
62052ab1 | 1239 | * suspended after its runtime PM has been disabled. |
5e928f77 RW |
1240 | * |
1241 | * If @check_resume is set and there's a resume request pending when | |
1242 | * __pm_runtime_disable() is called and power.disable_depth is zero, the | |
62052ab1 | 1243 | * function will wake up the device before disabling its runtime PM. |
5e928f77 RW |
1244 | */ |
1245 | void __pm_runtime_disable(struct device *dev, bool check_resume) | |
1246 | { | |
1247 | spin_lock_irq(&dev->power.lock); | |
1248 | ||
1249 | if (dev->power.disable_depth > 0) { | |
1250 | dev->power.disable_depth++; | |
1251 | goto out; | |
1252 | } | |
1253 | ||
1254 | /* | |
1255 | * Wake up the device if there's a resume request pending, because that | |
62052ab1 | 1256 | * means there probably is some I/O to process and disabling runtime PM |
5e928f77 RW |
1257 | * shouldn't prevent the device from processing the I/O. |
1258 | */ | |
1259 | if (check_resume && dev->power.request_pending | |
1260 | && dev->power.request == RPM_REQ_RESUME) { | |
1261 | /* | |
1262 | * Prevent suspends and idle notifications from being carried | |
1263 | * out after we have woken up the device. | |
1264 | */ | |
1265 | pm_runtime_get_noresume(dev); | |
1266 | ||
140a6c94 | 1267 | rpm_resume(dev, 0); |
5e928f77 RW |
1268 | |
1269 | pm_runtime_put_noidle(dev); | |
1270 | } | |
1271 | ||
1272 | if (!dev->power.disable_depth++) | |
1273 | __pm_runtime_barrier(dev); | |
1274 | ||
1275 | out: | |
1276 | spin_unlock_irq(&dev->power.lock); | |
1277 | } | |
1278 | EXPORT_SYMBOL_GPL(__pm_runtime_disable); | |
1279 | ||
1280 | /** | |
62052ab1 | 1281 | * pm_runtime_enable - Enable runtime PM of a device. |
5e928f77 RW |
1282 | * @dev: Device to handle. |
1283 | */ | |
1284 | void pm_runtime_enable(struct device *dev) | |
1285 | { | |
1286 | unsigned long flags; | |
1287 | ||
1288 | spin_lock_irqsave(&dev->power.lock, flags); | |
1289 | ||
1290 | if (dev->power.disable_depth > 0) | |
1291 | dev->power.disable_depth--; | |
1292 | else | |
1293 | dev_warn(dev, "Unbalanced %s!\n", __func__); | |
1294 | ||
f8817f61 RW |
1295 | WARN(!dev->power.disable_depth && |
1296 | dev->power.runtime_status == RPM_SUSPENDED && | |
1297 | !dev->power.ignore_children && | |
1298 | atomic_read(&dev->power.child_count) > 0, | |
1299 | "Enabling runtime PM for inactive device (%s) with active children\n", | |
1300 | dev_name(dev)); | |
1301 | ||
5e928f77 RW |
1302 | spin_unlock_irqrestore(&dev->power.lock, flags); |
1303 | } | |
1304 | EXPORT_SYMBOL_GPL(pm_runtime_enable); | |
1305 | ||
53823639 | 1306 | /** |
62052ab1 | 1307 | * pm_runtime_forbid - Block runtime PM of a device. |
53823639 RW |
1308 | * @dev: Device to handle. |
1309 | * | |
1310 | * Increase the device's usage count and clear its power.runtime_auto flag, | |
1311 | * so that it cannot be suspended at run time until pm_runtime_allow() is called | |
1312 | * for it. | |
1313 | */ | |
1314 | void pm_runtime_forbid(struct device *dev) | |
1315 | { | |
1316 | spin_lock_irq(&dev->power.lock); | |
1317 | if (!dev->power.runtime_auto) | |
1318 | goto out; | |
1319 | ||
1320 | dev->power.runtime_auto = false; | |
1321 | atomic_inc(&dev->power.usage_count); | |
140a6c94 | 1322 | rpm_resume(dev, 0); |
53823639 RW |
1323 | |
1324 | out: | |
1325 | spin_unlock_irq(&dev->power.lock); | |
1326 | } | |
1327 | EXPORT_SYMBOL_GPL(pm_runtime_forbid); | |
1328 | ||
1329 | /** | |
62052ab1 | 1330 | * pm_runtime_allow - Unblock runtime PM of a device. |
53823639 RW |
1331 | * @dev: Device to handle. |
1332 | * | |
1333 | * Decrease the device's usage count and set its power.runtime_auto flag. | |
1334 | */ | |
1335 | void pm_runtime_allow(struct device *dev) | |
1336 | { | |
1337 | spin_lock_irq(&dev->power.lock); | |
1338 | if (dev->power.runtime_auto) | |
1339 | goto out; | |
1340 | ||
1341 | dev->power.runtime_auto = true; | |
1342 | if (atomic_dec_and_test(&dev->power.usage_count)) | |
fe7450b0 | 1343 | rpm_idle(dev, RPM_AUTO | RPM_ASYNC); |
53823639 RW |
1344 | |
1345 | out: | |
1346 | spin_unlock_irq(&dev->power.lock); | |
1347 | } | |
1348 | EXPORT_SYMBOL_GPL(pm_runtime_allow); | |
1349 | ||
7490e442 | 1350 | /** |
62052ab1 | 1351 | * pm_runtime_no_callbacks - Ignore runtime PM callbacks for a device. |
7490e442 AS |
1352 | * @dev: Device to handle. |
1353 | * | |
1354 | * Set the power.no_callbacks flag, which tells the PM core that this | |
62052ab1 RW |
1355 | * device is power-managed through its parent and has no runtime PM |
1356 | * callbacks of its own. The runtime sysfs attributes will be removed. | |
7490e442 AS |
1357 | */ |
1358 | void pm_runtime_no_callbacks(struct device *dev) | |
1359 | { | |
1360 | spin_lock_irq(&dev->power.lock); | |
1361 | dev->power.no_callbacks = 1; | |
1362 | spin_unlock_irq(&dev->power.lock); | |
1363 | if (device_is_registered(dev)) | |
1364 | rpm_sysfs_remove(dev); | |
1365 | } | |
1366 | EXPORT_SYMBOL_GPL(pm_runtime_no_callbacks); | |
1367 | ||
c7b61de5 AS |
1368 | /** |
1369 | * pm_runtime_irq_safe - Leave interrupts disabled during callbacks. | |
1370 | * @dev: Device to handle | |
1371 | * | |
1372 | * Set the power.irq_safe flag, which tells the PM core that the | |
1373 | * ->runtime_suspend() and ->runtime_resume() callbacks for this device should | |
1374 | * always be invoked with the spinlock held and interrupts disabled. It also | |
1375 | * causes the parent's usage counter to be permanently incremented, preventing | |
1376 | * the parent from runtime suspending -- otherwise an irq-safe child might have | |
1377 | * to wait for a non-irq-safe parent. | |
1378 | */ | |
1379 | void pm_runtime_irq_safe(struct device *dev) | |
1380 | { | |
1381 | if (dev->parent) | |
1382 | pm_runtime_get_sync(dev->parent); | |
1383 | spin_lock_irq(&dev->power.lock); | |
1384 | dev->power.irq_safe = 1; | |
1385 | spin_unlock_irq(&dev->power.lock); | |
1386 | } | |
1387 | EXPORT_SYMBOL_GPL(pm_runtime_irq_safe); | |
1388 | ||
15bcb91d AS |
1389 | /** |
1390 | * update_autosuspend - Handle a change to a device's autosuspend settings. | |
1391 | * @dev: Device to handle. | |
1392 | * @old_delay: The former autosuspend_delay value. | |
1393 | * @old_use: The former use_autosuspend value. | |
1394 | * | |
1395 | * Prevent runtime suspend if the new delay is negative and use_autosuspend is | |
1396 | * set; otherwise allow it. Send an idle notification if suspends are allowed. | |
1397 | * | |
1398 | * This function must be called under dev->power.lock with interrupts disabled. | |
1399 | */ | |
1400 | static void update_autosuspend(struct device *dev, int old_delay, int old_use) | |
1401 | { | |
1402 | int delay = dev->power.autosuspend_delay; | |
1403 | ||
1404 | /* Should runtime suspend be prevented now? */ | |
1405 | if (dev->power.use_autosuspend && delay < 0) { | |
1406 | ||
1407 | /* If it used to be allowed then prevent it. */ | |
1408 | if (!old_use || old_delay >= 0) { | |
1409 | atomic_inc(&dev->power.usage_count); | |
1410 | rpm_resume(dev, 0); | |
1411 | } | |
1412 | } | |
1413 | ||
1414 | /* Runtime suspend should be allowed now. */ | |
1415 | else { | |
1416 | ||
1417 | /* If it used to be prevented then allow it. */ | |
1418 | if (old_use && old_delay < 0) | |
1419 | atomic_dec(&dev->power.usage_count); | |
1420 | ||
1421 | /* Maybe we can autosuspend now. */ | |
1422 | rpm_idle(dev, RPM_AUTO); | |
1423 | } | |
1424 | } | |
1425 | ||
1426 | /** | |
1427 | * pm_runtime_set_autosuspend_delay - Set a device's autosuspend_delay value. | |
1428 | * @dev: Device to handle. | |
1429 | * @delay: Value of the new delay in milliseconds. | |
1430 | * | |
1431 | * Set the device's power.autosuspend_delay value. If it changes to negative | |
62052ab1 RW |
1432 | * and the power.use_autosuspend flag is set, prevent runtime suspends. If it |
1433 | * changes the other way, allow runtime suspends. | |
15bcb91d AS |
1434 | */ |
1435 | void pm_runtime_set_autosuspend_delay(struct device *dev, int delay) | |
1436 | { | |
1437 | int old_delay, old_use; | |
1438 | ||
1439 | spin_lock_irq(&dev->power.lock); | |
1440 | old_delay = dev->power.autosuspend_delay; | |
1441 | old_use = dev->power.use_autosuspend; | |
1442 | dev->power.autosuspend_delay = delay; | |
1443 | update_autosuspend(dev, old_delay, old_use); | |
1444 | spin_unlock_irq(&dev->power.lock); | |
1445 | } | |
1446 | EXPORT_SYMBOL_GPL(pm_runtime_set_autosuspend_delay); | |
1447 | ||
1448 | /** | |
1449 | * __pm_runtime_use_autosuspend - Set a device's use_autosuspend flag. | |
1450 | * @dev: Device to handle. | |
1451 | * @use: New value for use_autosuspend. | |
1452 | * | |
62052ab1 | 1453 | * Set the device's power.use_autosuspend flag, and allow or prevent runtime |
15bcb91d AS |
1454 | * suspends as needed. |
1455 | */ | |
1456 | void __pm_runtime_use_autosuspend(struct device *dev, bool use) | |
1457 | { | |
1458 | int old_delay, old_use; | |
1459 | ||
1460 | spin_lock_irq(&dev->power.lock); | |
1461 | old_delay = dev->power.autosuspend_delay; | |
1462 | old_use = dev->power.use_autosuspend; | |
1463 | dev->power.use_autosuspend = use; | |
1464 | update_autosuspend(dev, old_delay, old_use); | |
1465 | spin_unlock_irq(&dev->power.lock); | |
1466 | } | |
1467 | EXPORT_SYMBOL_GPL(__pm_runtime_use_autosuspend); | |
1468 | ||
5e928f77 | 1469 | /** |
62052ab1 | 1470 | * pm_runtime_init - Initialize runtime PM fields in given device object. |
5e928f77 RW |
1471 | * @dev: Device object to initialize. |
1472 | */ | |
1473 | void pm_runtime_init(struct device *dev) | |
1474 | { | |
5e928f77 RW |
1475 | dev->power.runtime_status = RPM_SUSPENDED; |
1476 | dev->power.idle_notification = false; | |
1477 | ||
1478 | dev->power.disable_depth = 1; | |
1479 | atomic_set(&dev->power.usage_count, 0); | |
1480 | ||
1481 | dev->power.runtime_error = 0; | |
1482 | ||
1483 | atomic_set(&dev->power.child_count, 0); | |
1484 | pm_suspend_ignore_children(dev, false); | |
53823639 | 1485 | dev->power.runtime_auto = true; |
5e928f77 RW |
1486 | |
1487 | dev->power.request_pending = false; | |
1488 | dev->power.request = RPM_REQ_NONE; | |
1489 | dev->power.deferred_resume = false; | |
8d4b9d1b | 1490 | dev->power.accounting_timestamp = jiffies; |
5e928f77 RW |
1491 | INIT_WORK(&dev->power.work, pm_runtime_work); |
1492 | ||
1493 | dev->power.timer_expires = 0; | |
96428e98 | 1494 | timer_setup(&dev->power.suspend_timer, pm_suspend_timer_fn, 0); |
5e928f77 RW |
1495 | |
1496 | init_waitqueue_head(&dev->power.wait_queue); | |
1497 | } | |
1498 | ||
5de85b9d UH |
1499 | /** |
1500 | * pm_runtime_reinit - Re-initialize runtime PM fields in given device object. | |
1501 | * @dev: Device object to re-initialize. | |
1502 | */ | |
1503 | void pm_runtime_reinit(struct device *dev) | |
1504 | { | |
1505 | if (!pm_runtime_enabled(dev)) { | |
1506 | if (dev->power.runtime_status == RPM_ACTIVE) | |
1507 | pm_runtime_set_suspended(dev); | |
1508 | if (dev->power.irq_safe) { | |
1509 | spin_lock_irq(&dev->power.lock); | |
1510 | dev->power.irq_safe = 0; | |
1511 | spin_unlock_irq(&dev->power.lock); | |
1512 | if (dev->parent) | |
1513 | pm_runtime_put(dev->parent); | |
1514 | } | |
1515 | } | |
1516 | } | |
1517 | ||
5e928f77 RW |
1518 | /** |
1519 | * pm_runtime_remove - Prepare for removing a device from device hierarchy. | |
1520 | * @dev: Device object being removed from device hierarchy. | |
1521 | */ | |
1522 | void pm_runtime_remove(struct device *dev) | |
1523 | { | |
1524 | __pm_runtime_disable(dev, false); | |
5de85b9d | 1525 | pm_runtime_reinit(dev); |
5e928f77 | 1526 | } |
37f20416 | 1527 | |
21d5c57b RW |
1528 | /** |
1529 | * pm_runtime_clean_up_links - Prepare links to consumers for driver removal. | |
1530 | * @dev: Device whose driver is going to be removed. | |
1531 | * | |
1532 | * Check links from this device to any consumers and if any of them have active | |
1533 | * runtime PM references to the device, drop the usage counter of the device | |
1534 | * (once per link). | |
1535 | * | |
1536 | * Links with the DL_FLAG_STATELESS flag set are ignored. | |
1537 | * | |
1538 | * Since the device is guaranteed to be runtime-active at the point this is | |
1539 | * called, nothing else needs to be done here. | |
1540 | * | |
1541 | * Moreover, this is called after device_links_busy() has returned 'false', so | |
1542 | * the status of each link is guaranteed to be DL_STATE_SUPPLIER_UNBIND and | |
1543 | * therefore rpm_active can't be manipulated concurrently. | |
1544 | */ | |
1545 | void pm_runtime_clean_up_links(struct device *dev) | |
1546 | { | |
1547 | struct device_link *link; | |
1548 | int idx; | |
1549 | ||
1550 | idx = device_links_read_lock(); | |
1551 | ||
1552 | list_for_each_entry_rcu(link, &dev->links.consumers, s_node) { | |
1553 | if (link->flags & DL_FLAG_STATELESS) | |
1554 | continue; | |
1555 | ||
1556 | if (link->rpm_active) { | |
1557 | pm_runtime_put_noidle(dev); | |
1558 | link->rpm_active = false; | |
1559 | } | |
1560 | } | |
1561 | ||
1562 | device_links_read_unlock(idx); | |
1563 | } | |
1564 | ||
1565 | /** | |
1566 | * pm_runtime_get_suppliers - Resume and reference-count supplier devices. | |
1567 | * @dev: Consumer device. | |
1568 | */ | |
1569 | void pm_runtime_get_suppliers(struct device *dev) | |
1570 | { | |
1571 | struct device_link *link; | |
1572 | int idx; | |
1573 | ||
1574 | idx = device_links_read_lock(); | |
1575 | ||
1576 | list_for_each_entry_rcu(link, &dev->links.suppliers, c_node) | |
1577 | if (link->flags & DL_FLAG_PM_RUNTIME) | |
1578 | pm_runtime_get_sync(link->supplier); | |
1579 | ||
1580 | device_links_read_unlock(idx); | |
1581 | } | |
1582 | ||
1583 | /** | |
1584 | * pm_runtime_put_suppliers - Drop references to supplier devices. | |
1585 | * @dev: Consumer device. | |
1586 | */ | |
1587 | void pm_runtime_put_suppliers(struct device *dev) | |
1588 | { | |
1589 | struct device_link *link; | |
1590 | int idx; | |
1591 | ||
1592 | idx = device_links_read_lock(); | |
1593 | ||
1594 | list_for_each_entry_rcu(link, &dev->links.suppliers, c_node) | |
1595 | if (link->flags & DL_FLAG_PM_RUNTIME) | |
1596 | pm_runtime_put(link->supplier); | |
1597 | ||
1598 | device_links_read_unlock(idx); | |
1599 | } | |
1600 | ||
baa8809f RW |
1601 | void pm_runtime_new_link(struct device *dev) |
1602 | { | |
1603 | spin_lock_irq(&dev->power.lock); | |
1604 | dev->power.links_count++; | |
1605 | spin_unlock_irq(&dev->power.lock); | |
1606 | } | |
1607 | ||
1608 | void pm_runtime_drop_link(struct device *dev) | |
1609 | { | |
1610 | spin_lock_irq(&dev->power.lock); | |
1611 | WARN_ON(dev->power.links_count == 0); | |
1612 | dev->power.links_count--; | |
1613 | spin_unlock_irq(&dev->power.lock); | |
1614 | } | |
1615 | ||
4918e1f8 RW |
1616 | static bool pm_runtime_need_not_resume(struct device *dev) |
1617 | { | |
1618 | return atomic_read(&dev->power.usage_count) <= 1 && | |
1f5c6855 RW |
1619 | (atomic_read(&dev->power.child_count) == 0 || |
1620 | dev->power.ignore_children); | |
4918e1f8 RW |
1621 | } |
1622 | ||
37f20416 UH |
1623 | /** |
1624 | * pm_runtime_force_suspend - Force a device into suspend state if needed. | |
1625 | * @dev: Device to suspend. | |
1626 | * | |
1627 | * Disable runtime PM so we safely can check the device's runtime PM status and | |
4918e1f8 RW |
1628 | * if it is active, invoke its ->runtime_suspend callback to suspend it and |
1629 | * change its runtime PM status field to RPM_SUSPENDED. Also, if the device's | |
1630 | * usage and children counters don't indicate that the device was in use before | |
1631 | * the system-wide transition under way, decrement its parent's children counter | |
1632 | * (if there is a parent). Keep runtime PM disabled to preserve the state | |
1633 | * unless we encounter errors. | |
37f20416 UH |
1634 | * |
1635 | * Typically this function may be invoked from a system suspend callback to make | |
4918e1f8 RW |
1636 | * sure the device is put into low power state and it should only be used during |
1637 | * system-wide PM transitions to sleep states. It assumes that the analogous | |
1638 | * pm_runtime_force_resume() will be used to resume the device. | |
37f20416 UH |
1639 | */ |
1640 | int pm_runtime_force_suspend(struct device *dev) | |
1641 | { | |
1642 | int (*callback)(struct device *); | |
617fcb67 | 1643 | int ret; |
37f20416 UH |
1644 | |
1645 | pm_runtime_disable(dev); | |
37f20416 UH |
1646 | if (pm_runtime_status_suspended(dev)) |
1647 | return 0; | |
1648 | ||
dbcd2d72 | 1649 | callback = RPM_GET_CALLBACK(dev, runtime_suspend); |
37f20416 | 1650 | |
617fcb67 | 1651 | ret = callback ? callback(dev) : 0; |
37f20416 UH |
1652 | if (ret) |
1653 | goto err; | |
1654 | ||
1d9174fb | 1655 | /* |
4918e1f8 RW |
1656 | * If the device can stay in suspend after the system-wide transition |
1657 | * to the working state that will follow, drop the children counter of | |
1658 | * its parent, but set its status to RPM_SUSPENDED anyway in case this | |
1659 | * function will be called again for it in the meantime. | |
1d9174fb | 1660 | */ |
4918e1f8 RW |
1661 | if (pm_runtime_need_not_resume(dev)) |
1662 | pm_runtime_set_suspended(dev); | |
1663 | else | |
1664 | __update_runtime_status(dev, RPM_SUSPENDED); | |
1d9174fb | 1665 | |
37f20416 | 1666 | return 0; |
4918e1f8 | 1667 | |
37f20416 UH |
1668 | err: |
1669 | pm_runtime_enable(dev); | |
1670 | return ret; | |
1671 | } | |
1672 | EXPORT_SYMBOL_GPL(pm_runtime_force_suspend); | |
1673 | ||
1674 | /** | |
1d9174fb | 1675 | * pm_runtime_force_resume - Force a device into resume state if needed. |
37f20416 UH |
1676 | * @dev: Device to resume. |
1677 | * | |
1678 | * Prior invoking this function we expect the user to have brought the device | |
1679 | * into low power state by a call to pm_runtime_force_suspend(). Here we reverse | |
4918e1f8 RW |
1680 | * those actions and bring the device into full power, if it is expected to be |
1681 | * used on system resume. In the other case, we defer the resume to be managed | |
1682 | * via runtime PM. | |
37f20416 | 1683 | * |
1d9174fb | 1684 | * Typically this function may be invoked from a system resume callback. |
37f20416 UH |
1685 | */ |
1686 | int pm_runtime_force_resume(struct device *dev) | |
1687 | { | |
1688 | int (*callback)(struct device *); | |
1689 | int ret = 0; | |
1690 | ||
4918e1f8 | 1691 | if (!pm_runtime_status_suspended(dev) || pm_runtime_need_not_resume(dev)) |
9f5b5274 UH |
1692 | goto out; |
1693 | ||
1d9174fb | 1694 | /* |
4918e1f8 RW |
1695 | * The value of the parent's children counter is correct already, so |
1696 | * just update the status of the device. | |
1697 | */ | |
1698 | __update_runtime_status(dev, RPM_ACTIVE); | |
1d9174fb | 1699 | |
4918e1f8 | 1700 | callback = RPM_GET_CALLBACK(dev, runtime_resume); |
37f20416 | 1701 | |
617fcb67 | 1702 | ret = callback ? callback(dev) : 0; |
0ae3aeef UH |
1703 | if (ret) { |
1704 | pm_runtime_set_suspended(dev); | |
1705 | goto out; | |
1706 | } | |
1707 | ||
37f20416 UH |
1708 | pm_runtime_mark_last_busy(dev); |
1709 | out: | |
1710 | pm_runtime_enable(dev); | |
1711 | return ret; | |
1712 | } | |
1713 | EXPORT_SYMBOL_GPL(pm_runtime_force_resume); |