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 | ||
5b3cc15a | 10 | #include <linux/sched/mm.h> |
8234f673 VG |
11 | #include <linux/ktime.h> |
12 | #include <linux/hrtimer.h> | |
1b6bc32f | 13 | #include <linux/export.h> |
5e928f77 | 14 | #include <linux/pm_runtime.h> |
4990d4fe | 15 | #include <linux/pm_wakeirq.h> |
c3dc2f14 | 16 | #include <trace/events/rpm.h> |
21d5c57b RW |
17 | |
18 | #include "../base.h" | |
7490e442 | 19 | #include "power.h" |
5e928f77 | 20 | |
dbcd2d72 | 21 | typedef int (*pm_callback_t)(struct device *); |
5f59df79 | 22 | |
dbcd2d72 | 23 | static pm_callback_t __rpm_get_callback(struct device *dev, size_t cb_offset) |
5f59df79 | 24 | { |
dbcd2d72 AH |
25 | pm_callback_t cb; |
26 | const struct dev_pm_ops *ops; | |
27 | ||
28 | if (dev->pm_domain) | |
29 | ops = &dev->pm_domain->ops; | |
30 | else if (dev->type && dev->type->pm) | |
31 | ops = dev->type->pm; | |
32 | else if (dev->class && dev->class->pm) | |
33 | ops = dev->class->pm; | |
34 | else if (dev->bus && dev->bus->pm) | |
35 | ops = dev->bus->pm; | |
36 | else | |
37 | ops = NULL; | |
38 | ||
39 | if (ops) | |
40 | cb = *(pm_callback_t *)((void *)ops + cb_offset); | |
41 | else | |
42 | cb = NULL; | |
43 | ||
44 | if (!cb && dev->driver && dev->driver->pm) | |
45 | cb = *(pm_callback_t *)((void *)dev->driver->pm + cb_offset); | |
46 | ||
47 | return cb; | |
5f59df79 UH |
48 | } |
49 | ||
dbcd2d72 AH |
50 | #define RPM_GET_CALLBACK(dev, callback) \ |
51 | __rpm_get_callback(dev, offsetof(struct dev_pm_ops, callback)) | |
52 | ||
140a6c94 | 53 | static int rpm_resume(struct device *dev, int rpmflags); |
7490e442 | 54 | static int rpm_suspend(struct device *dev, int rpmflags); |
5e928f77 | 55 | |
4769373c AS |
56 | /** |
57 | * update_pm_runtime_accounting - Update the time accounting of power states | |
58 | * @dev: Device to update the accounting for | |
59 | * | |
60 | * In order to be able to have time accounting of the various power states | |
61 | * (as used by programs such as PowerTOP to show the effectiveness of runtime | |
62 | * PM), we need to track the time spent in each state. | |
63 | * update_pm_runtime_accounting must be called each time before the | |
64 | * runtime_status field is updated, to account the time in the old state | |
65 | * correctly. | |
66 | */ | |
67 | void update_pm_runtime_accounting(struct device *dev) | |
68 | { | |
fed7e88c | 69 | u64 now, last, delta; |
4769373c | 70 | |
fed7e88c VG |
71 | if (dev->power.disable_depth > 0) |
72 | return; | |
73 | ||
74 | last = dev->power.accounting_timestamp; | |
4769373c | 75 | |
fed7e88c | 76 | now = ktime_get_mono_fast_ns(); |
4769373c AS |
77 | dev->power.accounting_timestamp = now; |
78 | ||
c155f649 VG |
79 | /* |
80 | * Because ktime_get_mono_fast_ns() is not monotonic during | |
81 | * timekeeping updates, ensure that 'now' is after the last saved | |
82 | * timesptamp. | |
83 | */ | |
84 | if (now < last) | |
4769373c AS |
85 | return; |
86 | ||
c155f649 VG |
87 | delta = now - last; |
88 | ||
4769373c | 89 | if (dev->power.runtime_status == RPM_SUSPENDED) |
a08c2a5a | 90 | dev->power.suspended_time += delta; |
4769373c | 91 | else |
a08c2a5a | 92 | dev->power.active_time += delta; |
4769373c AS |
93 | } |
94 | ||
95 | static void __update_runtime_status(struct device *dev, enum rpm_status status) | |
96 | { | |
97 | update_pm_runtime_accounting(dev); | |
98 | dev->power.runtime_status = status; | |
99 | } | |
100 | ||
8a62ffe2 VG |
101 | u64 pm_runtime_suspended_time(struct device *dev) |
102 | { | |
a08c2a5a TG |
103 | u64 time; |
104 | unsigned long flags; | |
8a62ffe2 VG |
105 | |
106 | spin_lock_irqsave(&dev->power.lock, flags); | |
107 | ||
108 | update_pm_runtime_accounting(dev); | |
a08c2a5a | 109 | time = dev->power.suspended_time; |
8a62ffe2 VG |
110 | |
111 | spin_unlock_irqrestore(&dev->power.lock, flags); | |
112 | ||
a08c2a5a | 113 | return time; |
8a62ffe2 VG |
114 | } |
115 | EXPORT_SYMBOL_GPL(pm_runtime_suspended_time); | |
116 | ||
5e928f77 RW |
117 | /** |
118 | * pm_runtime_deactivate_timer - Deactivate given device's suspend timer. | |
119 | * @dev: Device to handle. | |
120 | */ | |
121 | static void pm_runtime_deactivate_timer(struct device *dev) | |
122 | { | |
123 | if (dev->power.timer_expires > 0) { | |
74fb4486 | 124 | hrtimer_try_to_cancel(&dev->power.suspend_timer); |
5e928f77 RW |
125 | dev->power.timer_expires = 0; |
126 | } | |
127 | } | |
128 | ||
129 | /** | |
130 | * pm_runtime_cancel_pending - Deactivate suspend timer and cancel requests. | |
131 | * @dev: Device to handle. | |
132 | */ | |
133 | static void pm_runtime_cancel_pending(struct device *dev) | |
134 | { | |
135 | pm_runtime_deactivate_timer(dev); | |
136 | /* | |
137 | * In case there's a request pending, make sure its work function will | |
138 | * return without doing anything. | |
139 | */ | |
140 | dev->power.request = RPM_REQ_NONE; | |
141 | } | |
142 | ||
15bcb91d AS |
143 | /* |
144 | * pm_runtime_autosuspend_expiration - Get a device's autosuspend-delay expiration time. | |
145 | * @dev: Device to handle. | |
146 | * | |
147 | * Compute the autosuspend-delay expiration time based on the device's | |
148 | * power.last_busy time. If the delay has already expired or is disabled | |
149 | * (negative) or the power.use_autosuspend flag isn't set, return 0. | |
1f7b7081 | 150 | * Otherwise return the expiration time in nanoseconds (adjusted to be nonzero). |
15bcb91d AS |
151 | * |
152 | * This function may be called either with or without dev->power.lock held. | |
153 | * Either way it can be racy, since power.last_busy may be updated at any time. | |
154 | */ | |
8234f673 | 155 | u64 pm_runtime_autosuspend_expiration(struct device *dev) |
15bcb91d AS |
156 | { |
157 | int autosuspend_delay; | |
f800ea32 | 158 | u64 expires; |
15bcb91d AS |
159 | |
160 | if (!dev->power.use_autosuspend) | |
f800ea32 | 161 | return 0; |
15bcb91d | 162 | |
6aa7de05 | 163 | autosuspend_delay = READ_ONCE(dev->power.autosuspend_delay); |
15bcb91d | 164 | if (autosuspend_delay < 0) |
f800ea32 | 165 | return 0; |
15bcb91d | 166 | |
f800ea32 LM |
167 | expires = READ_ONCE(dev->power.last_busy); |
168 | expires += (u64)autosuspend_delay * NSEC_PER_MSEC; | |
169 | if (expires > ktime_get_mono_fast_ns()) | |
170 | return expires; /* Expires in the future */ | |
15bcb91d | 171 | |
f800ea32 | 172 | return 0; |
15bcb91d AS |
173 | } |
174 | EXPORT_SYMBOL_GPL(pm_runtime_autosuspend_expiration); | |
175 | ||
e823407f ML |
176 | static int dev_memalloc_noio(struct device *dev, void *data) |
177 | { | |
178 | return dev->power.memalloc_noio; | |
179 | } | |
180 | ||
181 | /* | |
182 | * pm_runtime_set_memalloc_noio - Set a device's memalloc_noio flag. | |
183 | * @dev: Device to handle. | |
184 | * @enable: True for setting the flag and False for clearing the flag. | |
185 | * | |
186 | * Set the flag for all devices in the path from the device to the | |
187 | * root device in the device tree if @enable is true, otherwise clear | |
188 | * the flag for devices in the path whose siblings don't set the flag. | |
189 | * | |
190 | * The function should only be called by block device, or network | |
191 | * device driver for solving the deadlock problem during runtime | |
192 | * resume/suspend: | |
193 | * | |
194 | * If memory allocation with GFP_KERNEL is called inside runtime | |
195 | * resume/suspend callback of any one of its ancestors(or the | |
196 | * block device itself), the deadlock may be triggered inside the | |
197 | * memory allocation since it might not complete until the block | |
198 | * device becomes active and the involed page I/O finishes. The | |
199 | * situation is pointed out first by Alan Stern. Network device | |
200 | * are involved in iSCSI kind of situation. | |
201 | * | |
202 | * The lock of dev_hotplug_mutex is held in the function for handling | |
203 | * hotplug race because pm_runtime_set_memalloc_noio() may be called | |
204 | * in async probe(). | |
205 | * | |
206 | * The function should be called between device_add() and device_del() | |
207 | * on the affected device(block/network device). | |
208 | */ | |
209 | void pm_runtime_set_memalloc_noio(struct device *dev, bool enable) | |
210 | { | |
211 | static DEFINE_MUTEX(dev_hotplug_mutex); | |
212 | ||
213 | mutex_lock(&dev_hotplug_mutex); | |
214 | for (;;) { | |
215 | bool enabled; | |
216 | ||
217 | /* hold power lock since bitfield is not SMP-safe. */ | |
218 | spin_lock_irq(&dev->power.lock); | |
219 | enabled = dev->power.memalloc_noio; | |
220 | dev->power.memalloc_noio = enable; | |
221 | spin_unlock_irq(&dev->power.lock); | |
222 | ||
223 | /* | |
224 | * not need to enable ancestors any more if the device | |
225 | * has been enabled. | |
226 | */ | |
227 | if (enabled && enable) | |
228 | break; | |
229 | ||
230 | dev = dev->parent; | |
231 | ||
232 | /* | |
233 | * clear flag of the parent device only if all the | |
234 | * children don't set the flag because ancestor's | |
235 | * flag was set by any one of the descendants. | |
236 | */ | |
237 | if (!dev || (!enable && | |
238 | device_for_each_child(dev, NULL, | |
239 | dev_memalloc_noio))) | |
240 | break; | |
241 | } | |
242 | mutex_unlock(&dev_hotplug_mutex); | |
243 | } | |
244 | EXPORT_SYMBOL_GPL(pm_runtime_set_memalloc_noio); | |
245 | ||
5e928f77 | 246 | /** |
1bfee5bc AS |
247 | * rpm_check_suspend_allowed - Test whether a device may be suspended. |
248 | * @dev: Device to test. | |
5e928f77 | 249 | */ |
1bfee5bc | 250 | static int rpm_check_suspend_allowed(struct device *dev) |
5e928f77 RW |
251 | { |
252 | int retval = 0; | |
253 | ||
5e928f77 RW |
254 | if (dev->power.runtime_error) |
255 | retval = -EINVAL; | |
632e270e RW |
256 | else if (dev->power.disable_depth > 0) |
257 | retval = -EACCES; | |
258 | else if (atomic_read(&dev->power.usage_count) > 0) | |
5e928f77 | 259 | retval = -EAGAIN; |
62006c17 UH |
260 | else if (!dev->power.ignore_children && |
261 | atomic_read(&dev->power.child_count)) | |
5e928f77 | 262 | retval = -EBUSY; |
1bfee5bc AS |
263 | |
264 | /* Pending resume requests take precedence over suspends. */ | |
265 | else if ((dev->power.deferred_resume | |
78ca7c37 | 266 | && dev->power.runtime_status == RPM_SUSPENDING) |
1bfee5bc AS |
267 | || (dev->power.request_pending |
268 | && dev->power.request == RPM_REQ_RESUME)) | |
269 | retval = -EAGAIN; | |
0759e80b | 270 | else if (__dev_pm_qos_read_value(dev) == 0) |
55d7ec45 | 271 | retval = -EPERM; |
1bfee5bc AS |
272 | else if (dev->power.runtime_status == RPM_SUSPENDED) |
273 | retval = 1; | |
274 | ||
275 | return retval; | |
276 | } | |
277 | ||
21d5c57b RW |
278 | static int rpm_get_suppliers(struct device *dev) |
279 | { | |
280 | struct device_link *link; | |
281 | ||
282 | list_for_each_entry_rcu(link, &dev->links.suppliers, c_node) { | |
283 | int retval; | |
284 | ||
285 | if (!(link->flags & DL_FLAG_PM_RUNTIME)) | |
286 | continue; | |
287 | ||
288 | if (READ_ONCE(link->status) == DL_STATE_SUPPLIER_UNBIND || | |
289 | link->rpm_active) | |
290 | continue; | |
291 | ||
292 | retval = pm_runtime_get_sync(link->supplier); | |
31eb7431 RW |
293 | /* Ignore suppliers with disabled runtime PM. */ |
294 | if (retval < 0 && retval != -EACCES) { | |
21d5c57b RW |
295 | pm_runtime_put_noidle(link->supplier); |
296 | return retval; | |
297 | } | |
298 | link->rpm_active = true; | |
299 | } | |
300 | return 0; | |
301 | } | |
302 | ||
303 | static void rpm_put_suppliers(struct device *dev) | |
304 | { | |
305 | struct device_link *link; | |
306 | ||
307 | list_for_each_entry_rcu(link, &dev->links.suppliers, c_node) | |
308 | if (link->rpm_active && | |
309 | READ_ONCE(link->status) != DL_STATE_SUPPLIER_UNBIND) { | |
310 | pm_runtime_put(link->supplier); | |
311 | link->rpm_active = false; | |
312 | } | |
313 | } | |
314 | ||
ad3c36a5 RW |
315 | /** |
316 | * __rpm_callback - Run a given runtime PM callback for a given device. | |
317 | * @cb: Runtime PM callback to run. | |
318 | * @dev: Device to run the callback for. | |
319 | */ | |
320 | static int __rpm_callback(int (*cb)(struct device *), struct device *dev) | |
321 | __releases(&dev->power.lock) __acquires(&dev->power.lock) | |
322 | { | |
21d5c57b | 323 | int retval, idx; |
baa8809f | 324 | bool use_links = dev->power.links_count > 0; |
ad3c36a5 | 325 | |
21d5c57b | 326 | if (dev->power.irq_safe) { |
ad3c36a5 | 327 | spin_unlock(&dev->power.lock); |
21d5c57b | 328 | } else { |
ad3c36a5 RW |
329 | spin_unlock_irq(&dev->power.lock); |
330 | ||
21d5c57b RW |
331 | /* |
332 | * Resume suppliers if necessary. | |
333 | * | |
334 | * The device's runtime PM status cannot change until this | |
335 | * routine returns, so it is safe to read the status outside of | |
336 | * the lock. | |
337 | */ | |
baa8809f | 338 | if (use_links && dev->power.runtime_status == RPM_RESUMING) { |
21d5c57b RW |
339 | idx = device_links_read_lock(); |
340 | ||
341 | retval = rpm_get_suppliers(dev); | |
342 | if (retval) | |
343 | goto fail; | |
344 | ||
345 | device_links_read_unlock(idx); | |
346 | } | |
347 | } | |
348 | ||
ad3c36a5 RW |
349 | retval = cb(dev); |
350 | ||
21d5c57b | 351 | if (dev->power.irq_safe) { |
ad3c36a5 | 352 | spin_lock(&dev->power.lock); |
21d5c57b RW |
353 | } else { |
354 | /* | |
355 | * If the device is suspending and the callback has returned | |
356 | * success, drop the usage counters of the suppliers that have | |
357 | * been reference counted on its resume. | |
358 | * | |
359 | * Do that if resume fails too. | |
360 | */ | |
baa8809f RW |
361 | if (use_links |
362 | && ((dev->power.runtime_status == RPM_SUSPENDING && !retval) | |
363 | || (dev->power.runtime_status == RPM_RESUMING && retval))) { | |
21d5c57b RW |
364 | idx = device_links_read_lock(); |
365 | ||
366 | fail: | |
367 | rpm_put_suppliers(dev); | |
368 | ||
369 | device_links_read_unlock(idx); | |
370 | } | |
371 | ||
ad3c36a5 | 372 | spin_lock_irq(&dev->power.lock); |
21d5c57b | 373 | } |
ad3c36a5 RW |
374 | |
375 | return retval; | |
376 | } | |
377 | ||
1bfee5bc | 378 | /** |
140a6c94 | 379 | * rpm_idle - Notify device bus type if the device can be suspended. |
1bfee5bc AS |
380 | * @dev: Device to notify the bus type about. |
381 | * @rpmflags: Flag bits. | |
382 | * | |
62052ab1 | 383 | * Check if the device's runtime PM status allows it to be suspended. If |
1bfee5bc AS |
384 | * another idle notification has been started earlier, return immediately. If |
385 | * the RPM_ASYNC flag is set then queue an idle-notification request; otherwise | |
d66e6db2 UH |
386 | * run the ->runtime_idle() callback directly. If the ->runtime_idle callback |
387 | * doesn't exist or if it returns 0, call rpm_suspend with the RPM_AUTO flag. | |
1bfee5bc AS |
388 | * |
389 | * This function must be called under dev->power.lock with interrupts disabled. | |
390 | */ | |
140a6c94 | 391 | static int rpm_idle(struct device *dev, int rpmflags) |
1bfee5bc | 392 | { |
71c63122 | 393 | int (*callback)(struct device *); |
1bfee5bc AS |
394 | int retval; |
395 | ||
d7737ce9 | 396 | trace_rpm_idle_rcuidle(dev, rpmflags); |
1bfee5bc AS |
397 | retval = rpm_check_suspend_allowed(dev); |
398 | if (retval < 0) | |
399 | ; /* Conditions are wrong. */ | |
400 | ||
401 | /* Idle notifications are allowed only in the RPM_ACTIVE state. */ | |
402 | else if (dev->power.runtime_status != RPM_ACTIVE) | |
403 | retval = -EAGAIN; | |
404 | ||
405 | /* | |
406 | * Any pending request other than an idle notification takes | |
407 | * precedence over us, except that the timer may be running. | |
408 | */ | |
409 | else if (dev->power.request_pending && | |
410 | dev->power.request > RPM_REQ_IDLE) | |
411 | retval = -EAGAIN; | |
412 | ||
413 | /* Act as though RPM_NOWAIT is always set. */ | |
414 | else if (dev->power.idle_notification) | |
415 | retval = -EINPROGRESS; | |
5e928f77 RW |
416 | if (retval) |
417 | goto out; | |
418 | ||
1bfee5bc AS |
419 | /* Pending requests need to be canceled. */ |
420 | dev->power.request = RPM_REQ_NONE; | |
421 | ||
45f0a85c | 422 | if (dev->power.no_callbacks) |
7490e442 | 423 | goto out; |
7490e442 | 424 | |
1bfee5bc AS |
425 | /* Carry out an asynchronous or a synchronous idle notification. */ |
426 | if (rpmflags & RPM_ASYNC) { | |
427 | dev->power.request = RPM_REQ_IDLE; | |
428 | if (!dev->power.request_pending) { | |
429 | dev->power.request_pending = true; | |
430 | queue_work(pm_wq, &dev->power.work); | |
5e928f77 | 431 | } |
d7737ce9 | 432 | trace_rpm_return_int_rcuidle(dev, _THIS_IP_, 0); |
45f0a85c | 433 | return 0; |
5e928f77 RW |
434 | } |
435 | ||
436 | dev->power.idle_notification = true; | |
437 | ||
dbcd2d72 | 438 | callback = RPM_GET_CALLBACK(dev, runtime_idle); |
35cd133c | 439 | |
ad3c36a5 | 440 | if (callback) |
45f0a85c | 441 | retval = __rpm_callback(callback, dev); |
5e928f77 RW |
442 | |
443 | dev->power.idle_notification = false; | |
444 | wake_up_all(&dev->power.wait_queue); | |
445 | ||
446 | out: | |
d7737ce9 | 447 | trace_rpm_return_int_rcuidle(dev, _THIS_IP_, retval); |
d66e6db2 | 448 | return retval ? retval : rpm_suspend(dev, rpmflags | RPM_AUTO); |
5e928f77 RW |
449 | } |
450 | ||
71c63122 RW |
451 | /** |
452 | * rpm_callback - Run a given runtime PM callback for a given device. | |
453 | * @cb: Runtime PM callback to run. | |
454 | * @dev: Device to run the callback for. | |
455 | */ | |
456 | static int rpm_callback(int (*cb)(struct device *), struct device *dev) | |
71c63122 RW |
457 | { |
458 | int retval; | |
459 | ||
460 | if (!cb) | |
461 | return -ENOSYS; | |
462 | ||
db88175f ML |
463 | if (dev->power.memalloc_noio) { |
464 | unsigned int noio_flag; | |
465 | ||
466 | /* | |
467 | * Deadlock might be caused if memory allocation with | |
468 | * GFP_KERNEL happens inside runtime_suspend and | |
469 | * runtime_resume callbacks of one block device's | |
470 | * ancestor or the block device itself. Network | |
471 | * device might be thought as part of iSCSI block | |
472 | * device, so network device and its ancestor should | |
473 | * be marked as memalloc_noio too. | |
474 | */ | |
475 | noio_flag = memalloc_noio_save(); | |
476 | retval = __rpm_callback(cb, dev); | |
477 | memalloc_noio_restore(noio_flag); | |
478 | } else { | |
479 | retval = __rpm_callback(cb, dev); | |
480 | } | |
71c63122 | 481 | |
71c63122 | 482 | dev->power.runtime_error = retval; |
632e270e | 483 | return retval != -EACCES ? retval : -EIO; |
71c63122 RW |
484 | } |
485 | ||
5e928f77 | 486 | /** |
62052ab1 | 487 | * rpm_suspend - Carry out runtime suspend of given device. |
5e928f77 | 488 | * @dev: Device to suspend. |
3f9af051 | 489 | * @rpmflags: Flag bits. |
5e928f77 | 490 | * |
47d8f0ba ML |
491 | * Check if the device's runtime PM status allows it to be suspended. |
492 | * Cancel a pending idle notification, autosuspend or suspend. If | |
493 | * another suspend has been started earlier, either return immediately | |
494 | * or wait for it to finish, depending on the RPM_NOWAIT and RPM_ASYNC | |
495 | * flags. If the RPM_ASYNC flag is set then queue a suspend request; | |
857b36c7 ML |
496 | * otherwise run the ->runtime_suspend() callback directly. When |
497 | * ->runtime_suspend succeeded, if a deferred resume was requested while | |
498 | * the callback was running then carry it out, otherwise send an idle | |
499 | * notification for its parent (if the suspend succeeded and both | |
500 | * ignore_children of parent->power and irq_safe of dev->power are not set). | |
886486b7 AS |
501 | * If ->runtime_suspend failed with -EAGAIN or -EBUSY, and if the RPM_AUTO |
502 | * flag is set and the next autosuspend-delay expiration time is in the | |
503 | * future, schedule another autosuspend attempt. | |
5e928f77 RW |
504 | * |
505 | * This function must be called under dev->power.lock with interrupts disabled. | |
506 | */ | |
140a6c94 | 507 | static int rpm_suspend(struct device *dev, int rpmflags) |
5e928f77 RW |
508 | __releases(&dev->power.lock) __acquires(&dev->power.lock) |
509 | { | |
71c63122 | 510 | int (*callback)(struct device *); |
5e928f77 | 511 | struct device *parent = NULL; |
1bfee5bc | 512 | int retval; |
5e928f77 | 513 | |
77893577 | 514 | trace_rpm_suspend_rcuidle(dev, rpmflags); |
5e928f77 RW |
515 | |
516 | repeat: | |
1bfee5bc | 517 | retval = rpm_check_suspend_allowed(dev); |
5e928f77 | 518 | |
1bfee5bc AS |
519 | if (retval < 0) |
520 | ; /* Conditions are wrong. */ | |
521 | ||
522 | /* Synchronous suspends are not allowed in the RPM_RESUMING state. */ | |
523 | else if (dev->power.runtime_status == RPM_RESUMING && | |
524 | !(rpmflags & RPM_ASYNC)) | |
5e928f77 | 525 | retval = -EAGAIN; |
1bfee5bc | 526 | if (retval) |
5e928f77 | 527 | goto out; |
5e928f77 | 528 | |
15bcb91d AS |
529 | /* If the autosuspend_delay time hasn't expired yet, reschedule. */ |
530 | if ((rpmflags & RPM_AUTO) | |
531 | && dev->power.runtime_status != RPM_SUSPENDING) { | |
8234f673 | 532 | u64 expires = pm_runtime_autosuspend_expiration(dev); |
15bcb91d AS |
533 | |
534 | if (expires != 0) { | |
535 | /* Pending requests need to be canceled. */ | |
536 | dev->power.request = RPM_REQ_NONE; | |
537 | ||
538 | /* | |
539 | * Optimization: If the timer is already running and is | |
540 | * set to expire at or before the autosuspend delay, | |
541 | * avoid the overhead of resetting it. Just let it | |
542 | * expire; pm_suspend_timer_fn() will take care of the | |
543 | * rest. | |
544 | */ | |
8234f673 VG |
545 | if (!(dev->power.timer_expires && |
546 | dev->power.timer_expires <= expires)) { | |
547 | /* | |
548 | * We add a slack of 25% to gather wakeups | |
549 | * without sacrificing the granularity. | |
550 | */ | |
ca27e4cd | 551 | u64 slack = (u64)READ_ONCE(dev->power.autosuspend_delay) * |
8234f673 VG |
552 | (NSEC_PER_MSEC >> 2); |
553 | ||
15bcb91d | 554 | dev->power.timer_expires = expires; |
8234f673 VG |
555 | hrtimer_start_range_ns(&dev->power.suspend_timer, |
556 | ns_to_ktime(expires), | |
557 | slack, | |
558 | HRTIMER_MODE_ABS); | |
15bcb91d AS |
559 | } |
560 | dev->power.timer_autosuspends = 1; | |
561 | goto out; | |
562 | } | |
563 | } | |
564 | ||
5e928f77 RW |
565 | /* Other scheduled or pending requests need to be canceled. */ |
566 | pm_runtime_cancel_pending(dev); | |
567 | ||
5e928f77 RW |
568 | if (dev->power.runtime_status == RPM_SUSPENDING) { |
569 | DEFINE_WAIT(wait); | |
570 | ||
1bfee5bc | 571 | if (rpmflags & (RPM_ASYNC | RPM_NOWAIT)) { |
5e928f77 RW |
572 | retval = -EINPROGRESS; |
573 | goto out; | |
574 | } | |
575 | ||
ad3c36a5 RW |
576 | if (dev->power.irq_safe) { |
577 | spin_unlock(&dev->power.lock); | |
578 | ||
579 | cpu_relax(); | |
580 | ||
581 | spin_lock(&dev->power.lock); | |
582 | goto repeat; | |
583 | } | |
584 | ||
5e928f77 RW |
585 | /* Wait for the other suspend running in parallel with us. */ |
586 | for (;;) { | |
587 | prepare_to_wait(&dev->power.wait_queue, &wait, | |
588 | TASK_UNINTERRUPTIBLE); | |
589 | if (dev->power.runtime_status != RPM_SUSPENDING) | |
590 | break; | |
591 | ||
592 | spin_unlock_irq(&dev->power.lock); | |
593 | ||
594 | schedule(); | |
595 | ||
596 | spin_lock_irq(&dev->power.lock); | |
597 | } | |
598 | finish_wait(&dev->power.wait_queue, &wait); | |
599 | goto repeat; | |
600 | } | |
601 | ||
7490e442 AS |
602 | if (dev->power.no_callbacks) |
603 | goto no_callback; /* Assume success. */ | |
604 | ||
1bfee5bc AS |
605 | /* Carry out an asynchronous or a synchronous suspend. */ |
606 | if (rpmflags & RPM_ASYNC) { | |
15bcb91d AS |
607 | dev->power.request = (rpmflags & RPM_AUTO) ? |
608 | RPM_REQ_AUTOSUSPEND : RPM_REQ_SUSPEND; | |
1bfee5bc AS |
609 | if (!dev->power.request_pending) { |
610 | dev->power.request_pending = true; | |
611 | queue_work(pm_wq, &dev->power.work); | |
612 | } | |
613 | goto out; | |
614 | } | |
615 | ||
8d4b9d1b | 616 | __update_runtime_status(dev, RPM_SUSPENDING); |
5e928f77 | 617 | |
dbcd2d72 | 618 | callback = RPM_GET_CALLBACK(dev, runtime_suspend); |
35cd133c | 619 | |
bed57030 | 620 | dev_pm_enable_wake_irq_check(dev, true); |
71c63122 | 621 | retval = rpm_callback(callback, dev); |
00dc9ad1 RW |
622 | if (retval) |
623 | goto fail; | |
886486b7 | 624 | |
7490e442 | 625 | no_callback: |
857b36c7 ML |
626 | __update_runtime_status(dev, RPM_SUSPENDED); |
627 | pm_runtime_deactivate_timer(dev); | |
5e928f77 | 628 | |
857b36c7 ML |
629 | if (dev->parent) { |
630 | parent = dev->parent; | |
631 | atomic_add_unless(&parent->power.child_count, -1, 0); | |
5e928f77 RW |
632 | } |
633 | wake_up_all(&dev->power.wait_queue); | |
634 | ||
635 | if (dev->power.deferred_resume) { | |
58a34de7 | 636 | dev->power.deferred_resume = false; |
140a6c94 | 637 | rpm_resume(dev, 0); |
5e928f77 RW |
638 | retval = -EAGAIN; |
639 | goto out; | |
640 | } | |
641 | ||
c3810c88 | 642 | /* Maybe the parent is now able to suspend. */ |
c7b61de5 | 643 | if (parent && !parent->power.ignore_children && !dev->power.irq_safe) { |
c3810c88 | 644 | spin_unlock(&dev->power.lock); |
5e928f77 | 645 | |
c3810c88 AS |
646 | spin_lock(&parent->power.lock); |
647 | rpm_idle(parent, RPM_ASYNC); | |
648 | spin_unlock(&parent->power.lock); | |
5e928f77 | 649 | |
c3810c88 | 650 | spin_lock(&dev->power.lock); |
5e928f77 RW |
651 | } |
652 | ||
653 | out: | |
77893577 | 654 | trace_rpm_return_int_rcuidle(dev, _THIS_IP_, retval); |
5e928f77 RW |
655 | |
656 | return retval; | |
00dc9ad1 RW |
657 | |
658 | fail: | |
bed57030 | 659 | dev_pm_disable_wake_irq_check(dev); |
00dc9ad1 | 660 | __update_runtime_status(dev, RPM_ACTIVE); |
00dc9ad1 | 661 | dev->power.deferred_resume = false; |
f2791d73 AS |
662 | wake_up_all(&dev->power.wait_queue); |
663 | ||
00dc9ad1 RW |
664 | if (retval == -EAGAIN || retval == -EBUSY) { |
665 | dev->power.runtime_error = 0; | |
666 | ||
667 | /* | |
668 | * If the callback routine failed an autosuspend, and | |
669 | * if the last_busy time has been updated so that there | |
670 | * is a new autosuspend expiration time, automatically | |
671 | * reschedule another autosuspend. | |
672 | */ | |
673 | if ((rpmflags & RPM_AUTO) && | |
674 | pm_runtime_autosuspend_expiration(dev) != 0) | |
675 | goto repeat; | |
676 | } else { | |
677 | pm_runtime_cancel_pending(dev); | |
678 | } | |
00dc9ad1 | 679 | goto out; |
5e928f77 RW |
680 | } |
681 | ||
682 | /** | |
62052ab1 | 683 | * rpm_resume - Carry out runtime resume of given device. |
5e928f77 | 684 | * @dev: Device to resume. |
3f9af051 | 685 | * @rpmflags: Flag bits. |
5e928f77 | 686 | * |
62052ab1 | 687 | * Check if the device's runtime PM status allows it to be resumed. Cancel |
1bfee5bc | 688 | * any scheduled or pending requests. If another resume has been started |
25985edc | 689 | * earlier, either return immediately or wait for it to finish, depending on the |
1bfee5bc AS |
690 | * RPM_NOWAIT and RPM_ASYNC flags. Similarly, if there's a suspend running in |
691 | * parallel with this function, either tell the other process to resume after | |
692 | * suspending (deferred_resume) or wait for it to finish. If the RPM_ASYNC | |
693 | * flag is set then queue a resume request; otherwise run the | |
694 | * ->runtime_resume() callback directly. Queue an idle notification for the | |
695 | * device if the resume succeeded. | |
5e928f77 RW |
696 | * |
697 | * This function must be called under dev->power.lock with interrupts disabled. | |
698 | */ | |
140a6c94 | 699 | static int rpm_resume(struct device *dev, int rpmflags) |
5e928f77 RW |
700 | __releases(&dev->power.lock) __acquires(&dev->power.lock) |
701 | { | |
71c63122 | 702 | int (*callback)(struct device *); |
5e928f77 RW |
703 | struct device *parent = NULL; |
704 | int retval = 0; | |
705 | ||
d44c950e | 706 | trace_rpm_resume_rcuidle(dev, rpmflags); |
5e928f77 RW |
707 | |
708 | repeat: | |
1bfee5bc | 709 | if (dev->power.runtime_error) |
5e928f77 | 710 | retval = -EINVAL; |
6f3c77b0 KH |
711 | else if (dev->power.disable_depth == 1 && dev->power.is_suspended |
712 | && dev->power.runtime_status == RPM_ACTIVE) | |
713 | retval = 1; | |
1bfee5bc | 714 | else if (dev->power.disable_depth > 0) |
632e270e | 715 | retval = -EACCES; |
1bfee5bc | 716 | if (retval) |
5e928f77 | 717 | goto out; |
5e928f77 | 718 | |
15bcb91d AS |
719 | /* |
720 | * Other scheduled or pending requests need to be canceled. Small | |
721 | * optimization: If an autosuspend timer is running, leave it running | |
722 | * rather than cancelling it now only to restart it again in the near | |
723 | * future. | |
724 | */ | |
725 | dev->power.request = RPM_REQ_NONE; | |
726 | if (!dev->power.timer_autosuspends) | |
727 | pm_runtime_deactivate_timer(dev); | |
5e928f77 | 728 | |
1bfee5bc | 729 | if (dev->power.runtime_status == RPM_ACTIVE) { |
5e928f77 | 730 | retval = 1; |
5e928f77 | 731 | goto out; |
1bfee5bc | 732 | } |
5e928f77 RW |
733 | |
734 | if (dev->power.runtime_status == RPM_RESUMING | |
735 | || dev->power.runtime_status == RPM_SUSPENDING) { | |
736 | DEFINE_WAIT(wait); | |
737 | ||
1bfee5bc | 738 | if (rpmflags & (RPM_ASYNC | RPM_NOWAIT)) { |
5e928f77 RW |
739 | if (dev->power.runtime_status == RPM_SUSPENDING) |
740 | dev->power.deferred_resume = true; | |
1bfee5bc AS |
741 | else |
742 | retval = -EINPROGRESS; | |
5e928f77 RW |
743 | goto out; |
744 | } | |
745 | ||
ad3c36a5 RW |
746 | if (dev->power.irq_safe) { |
747 | spin_unlock(&dev->power.lock); | |
748 | ||
749 | cpu_relax(); | |
750 | ||
751 | spin_lock(&dev->power.lock); | |
752 | goto repeat; | |
753 | } | |
754 | ||
5e928f77 RW |
755 | /* Wait for the operation carried out in parallel with us. */ |
756 | for (;;) { | |
757 | prepare_to_wait(&dev->power.wait_queue, &wait, | |
758 | TASK_UNINTERRUPTIBLE); | |
759 | if (dev->power.runtime_status != RPM_RESUMING | |
760 | && dev->power.runtime_status != RPM_SUSPENDING) | |
761 | break; | |
762 | ||
763 | spin_unlock_irq(&dev->power.lock); | |
764 | ||
765 | schedule(); | |
766 | ||
767 | spin_lock_irq(&dev->power.lock); | |
768 | } | |
769 | finish_wait(&dev->power.wait_queue, &wait); | |
770 | goto repeat; | |
771 | } | |
772 | ||
7490e442 AS |
773 | /* |
774 | * See if we can skip waking up the parent. This is safe only if | |
775 | * power.no_callbacks is set, because otherwise we don't know whether | |
776 | * the resume will actually succeed. | |
777 | */ | |
778 | if (dev->power.no_callbacks && !parent && dev->parent) { | |
d63be5f9 | 779 | spin_lock_nested(&dev->parent->power.lock, SINGLE_DEPTH_NESTING); |
7490e442 AS |
780 | if (dev->parent->power.disable_depth > 0 |
781 | || dev->parent->power.ignore_children | |
782 | || dev->parent->power.runtime_status == RPM_ACTIVE) { | |
783 | atomic_inc(&dev->parent->power.child_count); | |
784 | spin_unlock(&dev->parent->power.lock); | |
7f321c26 | 785 | retval = 1; |
7490e442 AS |
786 | goto no_callback; /* Assume success. */ |
787 | } | |
788 | spin_unlock(&dev->parent->power.lock); | |
789 | } | |
790 | ||
1bfee5bc AS |
791 | /* Carry out an asynchronous or a synchronous resume. */ |
792 | if (rpmflags & RPM_ASYNC) { | |
793 | dev->power.request = RPM_REQ_RESUME; | |
794 | if (!dev->power.request_pending) { | |
795 | dev->power.request_pending = true; | |
796 | queue_work(pm_wq, &dev->power.work); | |
797 | } | |
798 | retval = 0; | |
799 | goto out; | |
800 | } | |
801 | ||
5e928f77 RW |
802 | if (!parent && dev->parent) { |
803 | /* | |
c7b61de5 AS |
804 | * Increment the parent's usage counter and resume it if |
805 | * necessary. Not needed if dev is irq-safe; then the | |
806 | * parent is permanently resumed. | |
5e928f77 RW |
807 | */ |
808 | parent = dev->parent; | |
c7b61de5 AS |
809 | if (dev->power.irq_safe) |
810 | goto skip_parent; | |
862f89b3 | 811 | spin_unlock(&dev->power.lock); |
5e928f77 RW |
812 | |
813 | pm_runtime_get_noresume(parent); | |
814 | ||
862f89b3 | 815 | spin_lock(&parent->power.lock); |
5e928f77 | 816 | /* |
216ef0b6 UH |
817 | * Resume the parent if it has runtime PM enabled and not been |
818 | * set to ignore its children. | |
5e928f77 RW |
819 | */ |
820 | if (!parent->power.disable_depth | |
821 | && !parent->power.ignore_children) { | |
140a6c94 | 822 | rpm_resume(parent, 0); |
5e928f77 RW |
823 | if (parent->power.runtime_status != RPM_ACTIVE) |
824 | retval = -EBUSY; | |
825 | } | |
862f89b3 | 826 | spin_unlock(&parent->power.lock); |
5e928f77 | 827 | |
862f89b3 | 828 | spin_lock(&dev->power.lock); |
5e928f77 RW |
829 | if (retval) |
830 | goto out; | |
831 | goto repeat; | |
832 | } | |
c7b61de5 | 833 | skip_parent: |
5e928f77 | 834 | |
7490e442 AS |
835 | if (dev->power.no_callbacks) |
836 | goto no_callback; /* Assume success. */ | |
837 | ||
8d4b9d1b | 838 | __update_runtime_status(dev, RPM_RESUMING); |
5e928f77 | 839 | |
dbcd2d72 | 840 | callback = RPM_GET_CALLBACK(dev, runtime_resume); |
35cd133c | 841 | |
bed57030 | 842 | dev_pm_disable_wake_irq_check(dev); |
71c63122 | 843 | retval = rpm_callback(callback, dev); |
5e928f77 | 844 | if (retval) { |
8d4b9d1b | 845 | __update_runtime_status(dev, RPM_SUSPENDED); |
5e928f77 | 846 | pm_runtime_cancel_pending(dev); |
bed57030 | 847 | dev_pm_enable_wake_irq_check(dev, false); |
5e928f77 | 848 | } else { |
7490e442 | 849 | no_callback: |
8d4b9d1b | 850 | __update_runtime_status(dev, RPM_ACTIVE); |
56f487c7 | 851 | pm_runtime_mark_last_busy(dev); |
5e928f77 RW |
852 | if (parent) |
853 | atomic_inc(&parent->power.child_count); | |
854 | } | |
855 | wake_up_all(&dev->power.wait_queue); | |
856 | ||
7f321c26 | 857 | if (retval >= 0) |
140a6c94 | 858 | rpm_idle(dev, RPM_ASYNC); |
5e928f77 RW |
859 | |
860 | out: | |
c7b61de5 | 861 | if (parent && !dev->power.irq_safe) { |
5e928f77 RW |
862 | spin_unlock_irq(&dev->power.lock); |
863 | ||
864 | pm_runtime_put(parent); | |
865 | ||
866 | spin_lock_irq(&dev->power.lock); | |
867 | } | |
868 | ||
d44c950e | 869 | trace_rpm_return_int_rcuidle(dev, _THIS_IP_, retval); |
5e928f77 RW |
870 | |
871 | return retval; | |
872 | } | |
873 | ||
5e928f77 | 874 | /** |
62052ab1 | 875 | * pm_runtime_work - Universal runtime PM work function. |
5e928f77 RW |
876 | * @work: Work structure used for scheduling the execution of this function. |
877 | * | |
878 | * Use @work to get the device object the work is to be done for, determine what | |
62052ab1 | 879 | * is to be done and execute the appropriate runtime PM function. |
5e928f77 RW |
880 | */ |
881 | static void pm_runtime_work(struct work_struct *work) | |
882 | { | |
883 | struct device *dev = container_of(work, struct device, power.work); | |
884 | enum rpm_request req; | |
885 | ||
886 | spin_lock_irq(&dev->power.lock); | |
887 | ||
888 | if (!dev->power.request_pending) | |
889 | goto out; | |
890 | ||
891 | req = dev->power.request; | |
892 | dev->power.request = RPM_REQ_NONE; | |
893 | dev->power.request_pending = false; | |
894 | ||
895 | switch (req) { | |
896 | case RPM_REQ_NONE: | |
897 | break; | |
898 | case RPM_REQ_IDLE: | |
140a6c94 | 899 | rpm_idle(dev, RPM_NOWAIT); |
5e928f77 RW |
900 | break; |
901 | case RPM_REQ_SUSPEND: | |
140a6c94 | 902 | rpm_suspend(dev, RPM_NOWAIT); |
5e928f77 | 903 | break; |
15bcb91d AS |
904 | case RPM_REQ_AUTOSUSPEND: |
905 | rpm_suspend(dev, RPM_NOWAIT | RPM_AUTO); | |
906 | break; | |
5e928f77 | 907 | case RPM_REQ_RESUME: |
140a6c94 | 908 | rpm_resume(dev, RPM_NOWAIT); |
5e928f77 RW |
909 | break; |
910 | } | |
911 | ||
912 | out: | |
913 | spin_unlock_irq(&dev->power.lock); | |
914 | } | |
915 | ||
5e928f77 RW |
916 | /** |
917 | * pm_suspend_timer_fn - Timer function for pm_schedule_suspend(). | |
918 | * @data: Device pointer passed by pm_schedule_suspend(). | |
919 | * | |
1bfee5bc | 920 | * Check if the time is right and queue a suspend request. |
5e928f77 | 921 | */ |
8234f673 | 922 | static enum hrtimer_restart pm_suspend_timer_fn(struct hrtimer *timer) |
5e928f77 | 923 | { |
8234f673 | 924 | struct device *dev = container_of(timer, struct device, power.suspend_timer); |
5e928f77 | 925 | unsigned long flags; |
8234f673 | 926 | u64 expires; |
5e928f77 RW |
927 | |
928 | spin_lock_irqsave(&dev->power.lock, flags); | |
929 | ||
930 | expires = dev->power.timer_expires; | |
1f7b7081 LM |
931 | /* |
932 | * If 'expires' is after the current time, we've been called | |
933 | * too early. | |
934 | */ | |
15efb47d | 935 | if (expires > 0 && expires < ktime_get_mono_fast_ns()) { |
5e928f77 | 936 | dev->power.timer_expires = 0; |
15bcb91d AS |
937 | rpm_suspend(dev, dev->power.timer_autosuspends ? |
938 | (RPM_ASYNC | RPM_AUTO) : RPM_ASYNC); | |
5e928f77 RW |
939 | } |
940 | ||
941 | spin_unlock_irqrestore(&dev->power.lock, flags); | |
8234f673 VG |
942 | |
943 | return HRTIMER_NORESTART; | |
5e928f77 RW |
944 | } |
945 | ||
946 | /** | |
947 | * pm_schedule_suspend - Set up a timer to submit a suspend request in future. | |
948 | * @dev: Device to suspend. | |
949 | * @delay: Time to wait before submitting a suspend request, in milliseconds. | |
950 | */ | |
951 | int pm_schedule_suspend(struct device *dev, unsigned int delay) | |
952 | { | |
953 | unsigned long flags; | |
15efb47d | 954 | u64 expires; |
1bfee5bc | 955 | int retval; |
5e928f77 RW |
956 | |
957 | spin_lock_irqsave(&dev->power.lock, flags); | |
958 | ||
5e928f77 | 959 | if (!delay) { |
140a6c94 | 960 | retval = rpm_suspend(dev, RPM_ASYNC); |
5e928f77 RW |
961 | goto out; |
962 | } | |
963 | ||
1bfee5bc | 964 | retval = rpm_check_suspend_allowed(dev); |
5e928f77 RW |
965 | if (retval) |
966 | goto out; | |
967 | ||
1bfee5bc AS |
968 | /* Other scheduled or pending requests need to be canceled. */ |
969 | pm_runtime_cancel_pending(dev); | |
970 | ||
15efb47d VG |
971 | expires = ktime_get_mono_fast_ns() + (u64)delay * NSEC_PER_MSEC; |
972 | dev->power.timer_expires = expires; | |
15bcb91d | 973 | dev->power.timer_autosuspends = 0; |
8234f673 | 974 | hrtimer_start(&dev->power.suspend_timer, expires, HRTIMER_MODE_ABS); |
5e928f77 RW |
975 | |
976 | out: | |
977 | spin_unlock_irqrestore(&dev->power.lock, flags); | |
978 | ||
979 | return retval; | |
980 | } | |
981 | EXPORT_SYMBOL_GPL(pm_schedule_suspend); | |
982 | ||
5e928f77 | 983 | /** |
62052ab1 | 984 | * __pm_runtime_idle - Entry point for runtime idle operations. |
140a6c94 AS |
985 | * @dev: Device to send idle notification for. |
986 | * @rpmflags: Flag bits. | |
987 | * | |
988 | * If the RPM_GET_PUT flag is set, decrement the device's usage count and | |
989 | * return immediately if it is larger than zero. Then carry out an idle | |
990 | * notification, either synchronous or asynchronous. | |
991 | * | |
311aab73 CC |
992 | * This routine may be called in atomic context if the RPM_ASYNC flag is set, |
993 | * or if pm_runtime_irq_safe() has been called. | |
5e928f77 | 994 | */ |
140a6c94 | 995 | int __pm_runtime_idle(struct device *dev, int rpmflags) |
5e928f77 RW |
996 | { |
997 | unsigned long flags; | |
998 | int retval; | |
999 | ||
140a6c94 AS |
1000 | if (rpmflags & RPM_GET_PUT) { |
1001 | if (!atomic_dec_and_test(&dev->power.usage_count)) | |
1002 | return 0; | |
1003 | } | |
1004 | ||
a9306a63 RW |
1005 | might_sleep_if(!(rpmflags & RPM_ASYNC) && !dev->power.irq_safe); |
1006 | ||
5e928f77 | 1007 | spin_lock_irqsave(&dev->power.lock, flags); |
140a6c94 | 1008 | retval = rpm_idle(dev, rpmflags); |
5e928f77 RW |
1009 | spin_unlock_irqrestore(&dev->power.lock, flags); |
1010 | ||
1011 | return retval; | |
1012 | } | |
140a6c94 | 1013 | EXPORT_SYMBOL_GPL(__pm_runtime_idle); |
5e928f77 RW |
1014 | |
1015 | /** | |
62052ab1 | 1016 | * __pm_runtime_suspend - Entry point for runtime put/suspend operations. |
140a6c94 | 1017 | * @dev: Device to suspend. |
3f9af051 | 1018 | * @rpmflags: Flag bits. |
5e928f77 | 1019 | * |
15bcb91d AS |
1020 | * If the RPM_GET_PUT flag is set, decrement the device's usage count and |
1021 | * return immediately if it is larger than zero. Then carry out a suspend, | |
1022 | * either synchronous or asynchronous. | |
140a6c94 | 1023 | * |
311aab73 CC |
1024 | * This routine may be called in atomic context if the RPM_ASYNC flag is set, |
1025 | * or if pm_runtime_irq_safe() has been called. | |
5e928f77 | 1026 | */ |
140a6c94 | 1027 | int __pm_runtime_suspend(struct device *dev, int rpmflags) |
5e928f77 | 1028 | { |
140a6c94 | 1029 | unsigned long flags; |
1d531c14 | 1030 | int retval; |
5e928f77 | 1031 | |
15bcb91d AS |
1032 | if (rpmflags & RPM_GET_PUT) { |
1033 | if (!atomic_dec_and_test(&dev->power.usage_count)) | |
1034 | return 0; | |
1035 | } | |
1036 | ||
a9306a63 RW |
1037 | might_sleep_if(!(rpmflags & RPM_ASYNC) && !dev->power.irq_safe); |
1038 | ||
140a6c94 AS |
1039 | spin_lock_irqsave(&dev->power.lock, flags); |
1040 | retval = rpm_suspend(dev, rpmflags); | |
1041 | spin_unlock_irqrestore(&dev->power.lock, flags); | |
5e928f77 RW |
1042 | |
1043 | return retval; | |
1044 | } | |
140a6c94 | 1045 | EXPORT_SYMBOL_GPL(__pm_runtime_suspend); |
5e928f77 RW |
1046 | |
1047 | /** | |
62052ab1 | 1048 | * __pm_runtime_resume - Entry point for runtime resume operations. |
140a6c94 | 1049 | * @dev: Device to resume. |
3f9af051 | 1050 | * @rpmflags: Flag bits. |
5e928f77 | 1051 | * |
140a6c94 AS |
1052 | * If the RPM_GET_PUT flag is set, increment the device's usage count. Then |
1053 | * carry out a resume, either synchronous or asynchronous. | |
1054 | * | |
311aab73 CC |
1055 | * This routine may be called in atomic context if the RPM_ASYNC flag is set, |
1056 | * or if pm_runtime_irq_safe() has been called. | |
5e928f77 | 1057 | */ |
140a6c94 | 1058 | int __pm_runtime_resume(struct device *dev, int rpmflags) |
5e928f77 | 1059 | { |
140a6c94 AS |
1060 | unsigned long flags; |
1061 | int retval; | |
5e928f77 | 1062 | |
a9306a63 RW |
1063 | might_sleep_if(!(rpmflags & RPM_ASYNC) && !dev->power.irq_safe && |
1064 | dev->power.runtime_status != RPM_ACTIVE); | |
311aab73 | 1065 | |
140a6c94 AS |
1066 | if (rpmflags & RPM_GET_PUT) |
1067 | atomic_inc(&dev->power.usage_count); | |
1068 | ||
1069 | spin_lock_irqsave(&dev->power.lock, flags); | |
1070 | retval = rpm_resume(dev, rpmflags); | |
1071 | spin_unlock_irqrestore(&dev->power.lock, flags); | |
5e928f77 RW |
1072 | |
1073 | return retval; | |
1074 | } | |
140a6c94 | 1075 | EXPORT_SYMBOL_GPL(__pm_runtime_resume); |
5e928f77 | 1076 | |
a436b6a1 RW |
1077 | /** |
1078 | * pm_runtime_get_if_in_use - Conditionally bump up the device's usage counter. | |
1079 | * @dev: Device to handle. | |
1080 | * | |
1081 | * Return -EINVAL if runtime PM is disabled for the device. | |
1082 | * | |
1083 | * If that's not the case and if the device's runtime PM status is RPM_ACTIVE | |
1084 | * and the runtime PM usage counter is nonzero, increment the counter and | |
1085 | * return 1. Otherwise return 0 without changing the counter. | |
1086 | */ | |
1087 | int pm_runtime_get_if_in_use(struct device *dev) | |
1088 | { | |
1089 | unsigned long flags; | |
1090 | int retval; | |
1091 | ||
1092 | spin_lock_irqsave(&dev->power.lock, flags); | |
1093 | retval = dev->power.disable_depth > 0 ? -EINVAL : | |
1094 | dev->power.runtime_status == RPM_ACTIVE | |
1095 | && atomic_inc_not_zero(&dev->power.usage_count); | |
1096 | spin_unlock_irqrestore(&dev->power.lock, flags); | |
1097 | return retval; | |
1098 | } | |
1099 | EXPORT_SYMBOL_GPL(pm_runtime_get_if_in_use); | |
1100 | ||
5e928f77 | 1101 | /** |
62052ab1 | 1102 | * __pm_runtime_set_status - Set runtime PM status of a device. |
5e928f77 | 1103 | * @dev: Device to handle. |
62052ab1 | 1104 | * @status: New runtime PM status of the device. |
5e928f77 | 1105 | * |
62052ab1 | 1106 | * If runtime PM of the device is disabled or its power.runtime_error field is |
5e928f77 RW |
1107 | * different from zero, the status may be changed either to RPM_ACTIVE, or to |
1108 | * RPM_SUSPENDED, as long as that reflects the actual state of the device. | |
1109 | * However, if the device has a parent and the parent is not active, and the | |
1110 | * parent's power.ignore_children flag is unset, the device's status cannot be | |
1111 | * set to RPM_ACTIVE, so -EBUSY is returned in that case. | |
1112 | * | |
1113 | * If successful, __pm_runtime_set_status() clears the power.runtime_error field | |
1114 | * and the device parent's counter of unsuspended children is modified to | |
1115 | * reflect the new status. If the new status is RPM_SUSPENDED, an idle | |
1116 | * notification request for the parent is submitted. | |
1117 | */ | |
1118 | int __pm_runtime_set_status(struct device *dev, unsigned int status) | |
1119 | { | |
1120 | struct device *parent = dev->parent; | |
1121 | unsigned long flags; | |
1122 | bool notify_parent = false; | |
1123 | int error = 0; | |
1124 | ||
1125 | if (status != RPM_ACTIVE && status != RPM_SUSPENDED) | |
1126 | return -EINVAL; | |
1127 | ||
1128 | spin_lock_irqsave(&dev->power.lock, flags); | |
1129 | ||
1130 | if (!dev->power.runtime_error && !dev->power.disable_depth) { | |
1131 | error = -EAGAIN; | |
1132 | goto out; | |
1133 | } | |
1134 | ||
f8817f61 | 1135 | if (dev->power.runtime_status == status || !parent) |
5e928f77 RW |
1136 | goto out_set; |
1137 | ||
1138 | if (status == RPM_SUSPENDED) { | |
f8817f61 RW |
1139 | atomic_add_unless(&parent->power.child_count, -1, 0); |
1140 | notify_parent = !parent->power.ignore_children; | |
1141 | } else { | |
bab636b9 | 1142 | spin_lock_nested(&parent->power.lock, SINGLE_DEPTH_NESTING); |
5e928f77 RW |
1143 | |
1144 | /* | |
1145 | * It is invalid to put an active child under a parent that is | |
62052ab1 | 1146 | * not active, has runtime PM enabled and the |
5e928f77 RW |
1147 | * 'power.ignore_children' flag unset. |
1148 | */ | |
1149 | if (!parent->power.disable_depth | |
1150 | && !parent->power.ignore_children | |
71723f95 LW |
1151 | && parent->power.runtime_status != RPM_ACTIVE) { |
1152 | dev_err(dev, "runtime PM trying to activate child device %s but parent (%s) is not active\n", | |
1153 | dev_name(dev), | |
1154 | dev_name(parent)); | |
5e928f77 | 1155 | error = -EBUSY; |
71723f95 | 1156 | } else if (dev->power.runtime_status == RPM_SUSPENDED) { |
965c4ac0 | 1157 | atomic_inc(&parent->power.child_count); |
71723f95 | 1158 | } |
5e928f77 | 1159 | |
862f89b3 | 1160 | spin_unlock(&parent->power.lock); |
5e928f77 RW |
1161 | |
1162 | if (error) | |
1163 | goto out; | |
1164 | } | |
1165 | ||
1166 | out_set: | |
8d4b9d1b | 1167 | __update_runtime_status(dev, status); |
5e928f77 RW |
1168 | dev->power.runtime_error = 0; |
1169 | out: | |
1170 | spin_unlock_irqrestore(&dev->power.lock, flags); | |
1171 | ||
1172 | if (notify_parent) | |
1173 | pm_request_idle(parent); | |
1174 | ||
1175 | return error; | |
1176 | } | |
1177 | EXPORT_SYMBOL_GPL(__pm_runtime_set_status); | |
1178 | ||
1179 | /** | |
1180 | * __pm_runtime_barrier - Cancel pending requests and wait for completions. | |
1181 | * @dev: Device to handle. | |
1182 | * | |
1183 | * Flush all pending requests for the device from pm_wq and wait for all | |
62052ab1 | 1184 | * runtime PM operations involving the device in progress to complete. |
5e928f77 RW |
1185 | * |
1186 | * Should be called under dev->power.lock with interrupts disabled. | |
1187 | */ | |
1188 | static void __pm_runtime_barrier(struct device *dev) | |
1189 | { | |
1190 | pm_runtime_deactivate_timer(dev); | |
1191 | ||
1192 | if (dev->power.request_pending) { | |
1193 | dev->power.request = RPM_REQ_NONE; | |
1194 | spin_unlock_irq(&dev->power.lock); | |
1195 | ||
1196 | cancel_work_sync(&dev->power.work); | |
1197 | ||
1198 | spin_lock_irq(&dev->power.lock); | |
1199 | dev->power.request_pending = false; | |
1200 | } | |
1201 | ||
1202 | if (dev->power.runtime_status == RPM_SUSPENDING | |
1203 | || dev->power.runtime_status == RPM_RESUMING | |
1204 | || dev->power.idle_notification) { | |
1205 | DEFINE_WAIT(wait); | |
1206 | ||
1207 | /* Suspend, wake-up or idle notification in progress. */ | |
1208 | for (;;) { | |
1209 | prepare_to_wait(&dev->power.wait_queue, &wait, | |
1210 | TASK_UNINTERRUPTIBLE); | |
1211 | if (dev->power.runtime_status != RPM_SUSPENDING | |
1212 | && dev->power.runtime_status != RPM_RESUMING | |
1213 | && !dev->power.idle_notification) | |
1214 | break; | |
1215 | spin_unlock_irq(&dev->power.lock); | |
1216 | ||
1217 | schedule(); | |
1218 | ||
1219 | spin_lock_irq(&dev->power.lock); | |
1220 | } | |
1221 | finish_wait(&dev->power.wait_queue, &wait); | |
1222 | } | |
1223 | } | |
1224 | ||
1225 | /** | |
1226 | * pm_runtime_barrier - Flush pending requests and wait for completions. | |
1227 | * @dev: Device to handle. | |
1228 | * | |
1229 | * Prevent the device from being suspended by incrementing its usage counter and | |
1230 | * if there's a pending resume request for the device, wake the device up. | |
1231 | * Next, make sure that all pending requests for the device have been flushed | |
62052ab1 | 1232 | * from pm_wq and wait for all runtime PM operations involving the device in |
5e928f77 RW |
1233 | * progress to complete. |
1234 | * | |
1235 | * Return value: | |
1236 | * 1, if there was a resume request pending and the device had to be woken up, | |
1237 | * 0, otherwise | |
1238 | */ | |
1239 | int pm_runtime_barrier(struct device *dev) | |
1240 | { | |
1241 | int retval = 0; | |
1242 | ||
1243 | pm_runtime_get_noresume(dev); | |
1244 | spin_lock_irq(&dev->power.lock); | |
1245 | ||
1246 | if (dev->power.request_pending | |
1247 | && dev->power.request == RPM_REQ_RESUME) { | |
140a6c94 | 1248 | rpm_resume(dev, 0); |
5e928f77 RW |
1249 | retval = 1; |
1250 | } | |
1251 | ||
1252 | __pm_runtime_barrier(dev); | |
1253 | ||
1254 | spin_unlock_irq(&dev->power.lock); | |
1255 | pm_runtime_put_noidle(dev); | |
1256 | ||
1257 | return retval; | |
1258 | } | |
1259 | EXPORT_SYMBOL_GPL(pm_runtime_barrier); | |
1260 | ||
1261 | /** | |
62052ab1 | 1262 | * __pm_runtime_disable - Disable runtime PM of a device. |
5e928f77 RW |
1263 | * @dev: Device to handle. |
1264 | * @check_resume: If set, check if there's a resume request for the device. | |
1265 | * | |
7b60894f | 1266 | * Increment power.disable_depth for the device and if it was zero previously, |
62052ab1 | 1267 | * cancel all pending runtime PM requests for the device and wait for all |
5e928f77 | 1268 | * operations in progress to complete. The device can be either active or |
62052ab1 | 1269 | * suspended after its runtime PM has been disabled. |
5e928f77 RW |
1270 | * |
1271 | * If @check_resume is set and there's a resume request pending when | |
1272 | * __pm_runtime_disable() is called and power.disable_depth is zero, the | |
62052ab1 | 1273 | * function will wake up the device before disabling its runtime PM. |
5e928f77 RW |
1274 | */ |
1275 | void __pm_runtime_disable(struct device *dev, bool check_resume) | |
1276 | { | |
1277 | spin_lock_irq(&dev->power.lock); | |
1278 | ||
1279 | if (dev->power.disable_depth > 0) { | |
1280 | dev->power.disable_depth++; | |
1281 | goto out; | |
1282 | } | |
1283 | ||
1284 | /* | |
1285 | * Wake up the device if there's a resume request pending, because that | |
62052ab1 | 1286 | * means there probably is some I/O to process and disabling runtime PM |
5e928f77 RW |
1287 | * shouldn't prevent the device from processing the I/O. |
1288 | */ | |
1289 | if (check_resume && dev->power.request_pending | |
1290 | && dev->power.request == RPM_REQ_RESUME) { | |
1291 | /* | |
1292 | * Prevent suspends and idle notifications from being carried | |
1293 | * out after we have woken up the device. | |
1294 | */ | |
1295 | pm_runtime_get_noresume(dev); | |
1296 | ||
140a6c94 | 1297 | rpm_resume(dev, 0); |
5e928f77 RW |
1298 | |
1299 | pm_runtime_put_noidle(dev); | |
1300 | } | |
1301 | ||
fed7e88c VG |
1302 | /* Update time accounting before disabling PM-runtime. */ |
1303 | update_pm_runtime_accounting(dev); | |
1304 | ||
5e928f77 RW |
1305 | if (!dev->power.disable_depth++) |
1306 | __pm_runtime_barrier(dev); | |
1307 | ||
1308 | out: | |
1309 | spin_unlock_irq(&dev->power.lock); | |
1310 | } | |
1311 | EXPORT_SYMBOL_GPL(__pm_runtime_disable); | |
1312 | ||
1313 | /** | |
62052ab1 | 1314 | * pm_runtime_enable - Enable runtime PM of a device. |
5e928f77 RW |
1315 | * @dev: Device to handle. |
1316 | */ | |
1317 | void pm_runtime_enable(struct device *dev) | |
1318 | { | |
1319 | unsigned long flags; | |
1320 | ||
1321 | spin_lock_irqsave(&dev->power.lock, flags); | |
1322 | ||
58456488 | 1323 | if (dev->power.disable_depth > 0) { |
5e928f77 | 1324 | dev->power.disable_depth--; |
58456488 VG |
1325 | |
1326 | /* About to enable runtime pm, set accounting_timestamp to now */ | |
1327 | if (!dev->power.disable_depth) | |
c155f649 | 1328 | dev->power.accounting_timestamp = ktime_get_mono_fast_ns(); |
58456488 | 1329 | } else { |
5e928f77 | 1330 | dev_warn(dev, "Unbalanced %s!\n", __func__); |
58456488 | 1331 | } |
5e928f77 | 1332 | |
f8817f61 RW |
1333 | WARN(!dev->power.disable_depth && |
1334 | dev->power.runtime_status == RPM_SUSPENDED && | |
1335 | !dev->power.ignore_children && | |
1336 | atomic_read(&dev->power.child_count) > 0, | |
1337 | "Enabling runtime PM for inactive device (%s) with active children\n", | |
1338 | dev_name(dev)); | |
1339 | ||
5e928f77 RW |
1340 | spin_unlock_irqrestore(&dev->power.lock, flags); |
1341 | } | |
1342 | EXPORT_SYMBOL_GPL(pm_runtime_enable); | |
1343 | ||
53823639 | 1344 | /** |
62052ab1 | 1345 | * pm_runtime_forbid - Block runtime PM of a device. |
53823639 RW |
1346 | * @dev: Device to handle. |
1347 | * | |
1348 | * Increase the device's usage count and clear its power.runtime_auto flag, | |
1349 | * so that it cannot be suspended at run time until pm_runtime_allow() is called | |
1350 | * for it. | |
1351 | */ | |
1352 | void pm_runtime_forbid(struct device *dev) | |
1353 | { | |
1354 | spin_lock_irq(&dev->power.lock); | |
1355 | if (!dev->power.runtime_auto) | |
1356 | goto out; | |
1357 | ||
1358 | dev->power.runtime_auto = false; | |
1359 | atomic_inc(&dev->power.usage_count); | |
140a6c94 | 1360 | rpm_resume(dev, 0); |
53823639 RW |
1361 | |
1362 | out: | |
1363 | spin_unlock_irq(&dev->power.lock); | |
1364 | } | |
1365 | EXPORT_SYMBOL_GPL(pm_runtime_forbid); | |
1366 | ||
1367 | /** | |
62052ab1 | 1368 | * pm_runtime_allow - Unblock runtime PM of a device. |
53823639 RW |
1369 | * @dev: Device to handle. |
1370 | * | |
1371 | * Decrease the device's usage count and set its power.runtime_auto flag. | |
1372 | */ | |
1373 | void pm_runtime_allow(struct device *dev) | |
1374 | { | |
1375 | spin_lock_irq(&dev->power.lock); | |
1376 | if (dev->power.runtime_auto) | |
1377 | goto out; | |
1378 | ||
1379 | dev->power.runtime_auto = true; | |
1380 | if (atomic_dec_and_test(&dev->power.usage_count)) | |
fe7450b0 | 1381 | rpm_idle(dev, RPM_AUTO | RPM_ASYNC); |
53823639 RW |
1382 | |
1383 | out: | |
1384 | spin_unlock_irq(&dev->power.lock); | |
1385 | } | |
1386 | EXPORT_SYMBOL_GPL(pm_runtime_allow); | |
1387 | ||
7490e442 | 1388 | /** |
62052ab1 | 1389 | * pm_runtime_no_callbacks - Ignore runtime PM callbacks for a device. |
7490e442 AS |
1390 | * @dev: Device to handle. |
1391 | * | |
1392 | * Set the power.no_callbacks flag, which tells the PM core that this | |
62052ab1 RW |
1393 | * device is power-managed through its parent and has no runtime PM |
1394 | * callbacks of its own. The runtime sysfs attributes will be removed. | |
7490e442 AS |
1395 | */ |
1396 | void pm_runtime_no_callbacks(struct device *dev) | |
1397 | { | |
1398 | spin_lock_irq(&dev->power.lock); | |
1399 | dev->power.no_callbacks = 1; | |
1400 | spin_unlock_irq(&dev->power.lock); | |
1401 | if (device_is_registered(dev)) | |
1402 | rpm_sysfs_remove(dev); | |
1403 | } | |
1404 | EXPORT_SYMBOL_GPL(pm_runtime_no_callbacks); | |
1405 | ||
c7b61de5 AS |
1406 | /** |
1407 | * pm_runtime_irq_safe - Leave interrupts disabled during callbacks. | |
1408 | * @dev: Device to handle | |
1409 | * | |
1410 | * Set the power.irq_safe flag, which tells the PM core that the | |
1411 | * ->runtime_suspend() and ->runtime_resume() callbacks for this device should | |
1412 | * always be invoked with the spinlock held and interrupts disabled. It also | |
1413 | * causes the parent's usage counter to be permanently incremented, preventing | |
1414 | * the parent from runtime suspending -- otherwise an irq-safe child might have | |
1415 | * to wait for a non-irq-safe parent. | |
1416 | */ | |
1417 | void pm_runtime_irq_safe(struct device *dev) | |
1418 | { | |
1419 | if (dev->parent) | |
1420 | pm_runtime_get_sync(dev->parent); | |
1421 | spin_lock_irq(&dev->power.lock); | |
1422 | dev->power.irq_safe = 1; | |
1423 | spin_unlock_irq(&dev->power.lock); | |
1424 | } | |
1425 | EXPORT_SYMBOL_GPL(pm_runtime_irq_safe); | |
1426 | ||
15bcb91d AS |
1427 | /** |
1428 | * update_autosuspend - Handle a change to a device's autosuspend settings. | |
1429 | * @dev: Device to handle. | |
1430 | * @old_delay: The former autosuspend_delay value. | |
1431 | * @old_use: The former use_autosuspend value. | |
1432 | * | |
1433 | * Prevent runtime suspend if the new delay is negative and use_autosuspend is | |
1434 | * set; otherwise allow it. Send an idle notification if suspends are allowed. | |
1435 | * | |
1436 | * This function must be called under dev->power.lock with interrupts disabled. | |
1437 | */ | |
1438 | static void update_autosuspend(struct device *dev, int old_delay, int old_use) | |
1439 | { | |
1440 | int delay = dev->power.autosuspend_delay; | |
1441 | ||
1442 | /* Should runtime suspend be prevented now? */ | |
1443 | if (dev->power.use_autosuspend && delay < 0) { | |
1444 | ||
1445 | /* If it used to be allowed then prevent it. */ | |
1446 | if (!old_use || old_delay >= 0) { | |
1447 | atomic_inc(&dev->power.usage_count); | |
1448 | rpm_resume(dev, 0); | |
1449 | } | |
1450 | } | |
1451 | ||
1452 | /* Runtime suspend should be allowed now. */ | |
1453 | else { | |
1454 | ||
1455 | /* If it used to be prevented then allow it. */ | |
1456 | if (old_use && old_delay < 0) | |
1457 | atomic_dec(&dev->power.usage_count); | |
1458 | ||
1459 | /* Maybe we can autosuspend now. */ | |
1460 | rpm_idle(dev, RPM_AUTO); | |
1461 | } | |
1462 | } | |
1463 | ||
1464 | /** | |
1465 | * pm_runtime_set_autosuspend_delay - Set a device's autosuspend_delay value. | |
1466 | * @dev: Device to handle. | |
1467 | * @delay: Value of the new delay in milliseconds. | |
1468 | * | |
1469 | * Set the device's power.autosuspend_delay value. If it changes to negative | |
62052ab1 RW |
1470 | * and the power.use_autosuspend flag is set, prevent runtime suspends. If it |
1471 | * changes the other way, allow runtime suspends. | |
15bcb91d AS |
1472 | */ |
1473 | void pm_runtime_set_autosuspend_delay(struct device *dev, int delay) | |
1474 | { | |
1475 | int old_delay, old_use; | |
1476 | ||
1477 | spin_lock_irq(&dev->power.lock); | |
1478 | old_delay = dev->power.autosuspend_delay; | |
1479 | old_use = dev->power.use_autosuspend; | |
1480 | dev->power.autosuspend_delay = delay; | |
1481 | update_autosuspend(dev, old_delay, old_use); | |
1482 | spin_unlock_irq(&dev->power.lock); | |
1483 | } | |
1484 | EXPORT_SYMBOL_GPL(pm_runtime_set_autosuspend_delay); | |
1485 | ||
1486 | /** | |
1487 | * __pm_runtime_use_autosuspend - Set a device's use_autosuspend flag. | |
1488 | * @dev: Device to handle. | |
1489 | * @use: New value for use_autosuspend. | |
1490 | * | |
62052ab1 | 1491 | * Set the device's power.use_autosuspend flag, and allow or prevent runtime |
15bcb91d AS |
1492 | * suspends as needed. |
1493 | */ | |
1494 | void __pm_runtime_use_autosuspend(struct device *dev, bool use) | |
1495 | { | |
1496 | int old_delay, old_use; | |
1497 | ||
1498 | spin_lock_irq(&dev->power.lock); | |
1499 | old_delay = dev->power.autosuspend_delay; | |
1500 | old_use = dev->power.use_autosuspend; | |
1501 | dev->power.use_autosuspend = use; | |
1502 | update_autosuspend(dev, old_delay, old_use); | |
1503 | spin_unlock_irq(&dev->power.lock); | |
1504 | } | |
1505 | EXPORT_SYMBOL_GPL(__pm_runtime_use_autosuspend); | |
1506 | ||
5e928f77 | 1507 | /** |
62052ab1 | 1508 | * pm_runtime_init - Initialize runtime PM fields in given device object. |
5e928f77 RW |
1509 | * @dev: Device object to initialize. |
1510 | */ | |
1511 | void pm_runtime_init(struct device *dev) | |
1512 | { | |
5e928f77 RW |
1513 | dev->power.runtime_status = RPM_SUSPENDED; |
1514 | dev->power.idle_notification = false; | |
1515 | ||
1516 | dev->power.disable_depth = 1; | |
1517 | atomic_set(&dev->power.usage_count, 0); | |
1518 | ||
1519 | dev->power.runtime_error = 0; | |
1520 | ||
1521 | atomic_set(&dev->power.child_count, 0); | |
1522 | pm_suspend_ignore_children(dev, false); | |
53823639 | 1523 | dev->power.runtime_auto = true; |
5e928f77 RW |
1524 | |
1525 | dev->power.request_pending = false; | |
1526 | dev->power.request = RPM_REQ_NONE; | |
1527 | dev->power.deferred_resume = false; | |
1528 | INIT_WORK(&dev->power.work, pm_runtime_work); | |
1529 | ||
1530 | dev->power.timer_expires = 0; | |
8234f673 VG |
1531 | hrtimer_init(&dev->power.suspend_timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS); |
1532 | dev->power.suspend_timer.function = pm_suspend_timer_fn; | |
5e928f77 RW |
1533 | |
1534 | init_waitqueue_head(&dev->power.wait_queue); | |
1535 | } | |
1536 | ||
5de85b9d UH |
1537 | /** |
1538 | * pm_runtime_reinit - Re-initialize runtime PM fields in given device object. | |
1539 | * @dev: Device object to re-initialize. | |
1540 | */ | |
1541 | void pm_runtime_reinit(struct device *dev) | |
1542 | { | |
1543 | if (!pm_runtime_enabled(dev)) { | |
1544 | if (dev->power.runtime_status == RPM_ACTIVE) | |
1545 | pm_runtime_set_suspended(dev); | |
1546 | if (dev->power.irq_safe) { | |
1547 | spin_lock_irq(&dev->power.lock); | |
1548 | dev->power.irq_safe = 0; | |
1549 | spin_unlock_irq(&dev->power.lock); | |
1550 | if (dev->parent) | |
1551 | pm_runtime_put(dev->parent); | |
1552 | } | |
1553 | } | |
1554 | } | |
1555 | ||
5e928f77 RW |
1556 | /** |
1557 | * pm_runtime_remove - Prepare for removing a device from device hierarchy. | |
1558 | * @dev: Device object being removed from device hierarchy. | |
1559 | */ | |
1560 | void pm_runtime_remove(struct device *dev) | |
1561 | { | |
1562 | __pm_runtime_disable(dev, false); | |
5de85b9d | 1563 | pm_runtime_reinit(dev); |
5e928f77 | 1564 | } |
37f20416 | 1565 | |
21d5c57b RW |
1566 | /** |
1567 | * pm_runtime_clean_up_links - Prepare links to consumers for driver removal. | |
1568 | * @dev: Device whose driver is going to be removed. | |
1569 | * | |
1570 | * Check links from this device to any consumers and if any of them have active | |
1571 | * runtime PM references to the device, drop the usage counter of the device | |
1572 | * (once per link). | |
1573 | * | |
1574 | * Links with the DL_FLAG_STATELESS flag set are ignored. | |
1575 | * | |
1576 | * Since the device is guaranteed to be runtime-active at the point this is | |
1577 | * called, nothing else needs to be done here. | |
1578 | * | |
1579 | * Moreover, this is called after device_links_busy() has returned 'false', so | |
1580 | * the status of each link is guaranteed to be DL_STATE_SUPPLIER_UNBIND and | |
1581 | * therefore rpm_active can't be manipulated concurrently. | |
1582 | */ | |
1583 | void pm_runtime_clean_up_links(struct device *dev) | |
1584 | { | |
1585 | struct device_link *link; | |
1586 | int idx; | |
1587 | ||
1588 | idx = device_links_read_lock(); | |
1589 | ||
1590 | list_for_each_entry_rcu(link, &dev->links.consumers, s_node) { | |
1591 | if (link->flags & DL_FLAG_STATELESS) | |
1592 | continue; | |
1593 | ||
1594 | if (link->rpm_active) { | |
1595 | pm_runtime_put_noidle(dev); | |
1596 | link->rpm_active = false; | |
1597 | } | |
1598 | } | |
1599 | ||
1600 | device_links_read_unlock(idx); | |
1601 | } | |
1602 | ||
1603 | /** | |
b06c0b2f | 1604 | * pm_runtime_get_suppliers - Resume and reference-count supplier devices. |
21d5c57b RW |
1605 | * @dev: Consumer device. |
1606 | */ | |
b06c0b2f | 1607 | void pm_runtime_get_suppliers(struct device *dev) |
21d5c57b | 1608 | { |
b06c0b2f | 1609 | struct device_link *link; |
21d5c57b RW |
1610 | int idx; |
1611 | ||
1612 | idx = device_links_read_lock(); | |
1613 | ||
b06c0b2f RW |
1614 | list_for_each_entry_rcu(link, &dev->links.suppliers, c_node) |
1615 | if (link->flags & DL_FLAG_PM_RUNTIME) | |
1616 | pm_runtime_get_sync(link->supplier); | |
1617 | ||
1618 | device_links_read_unlock(idx); | |
1619 | } | |
1620 | ||
1621 | /** | |
1622 | * pm_runtime_put_suppliers - Drop references to supplier devices. | |
1623 | * @dev: Consumer device. | |
1624 | */ | |
1625 | void pm_runtime_put_suppliers(struct device *dev) | |
1626 | { | |
1627 | struct device_link *link; | |
1628 | int idx; | |
1629 | ||
1630 | idx = device_links_read_lock(); | |
1631 | ||
1632 | list_for_each_entry_rcu(link, &dev->links.suppliers, c_node) | |
1633 | if (link->flags & DL_FLAG_PM_RUNTIME) | |
1634 | pm_runtime_put(link->supplier); | |
21d5c57b RW |
1635 | |
1636 | device_links_read_unlock(idx); | |
1637 | } | |
1638 | ||
baa8809f RW |
1639 | void pm_runtime_new_link(struct device *dev) |
1640 | { | |
1641 | spin_lock_irq(&dev->power.lock); | |
1642 | dev->power.links_count++; | |
1643 | spin_unlock_irq(&dev->power.lock); | |
1644 | } | |
1645 | ||
1646 | void pm_runtime_drop_link(struct device *dev) | |
1647 | { | |
a0504aec UH |
1648 | rpm_put_suppliers(dev); |
1649 | ||
baa8809f RW |
1650 | spin_lock_irq(&dev->power.lock); |
1651 | WARN_ON(dev->power.links_count == 0); | |
1652 | dev->power.links_count--; | |
1653 | spin_unlock_irq(&dev->power.lock); | |
1654 | } | |
1655 | ||
4918e1f8 RW |
1656 | static bool pm_runtime_need_not_resume(struct device *dev) |
1657 | { | |
1658 | return atomic_read(&dev->power.usage_count) <= 1 && | |
1f5c6855 RW |
1659 | (atomic_read(&dev->power.child_count) == 0 || |
1660 | dev->power.ignore_children); | |
4918e1f8 RW |
1661 | } |
1662 | ||
37f20416 UH |
1663 | /** |
1664 | * pm_runtime_force_suspend - Force a device into suspend state if needed. | |
1665 | * @dev: Device to suspend. | |
1666 | * | |
1667 | * Disable runtime PM so we safely can check the device's runtime PM status and | |
4918e1f8 RW |
1668 | * if it is active, invoke its ->runtime_suspend callback to suspend it and |
1669 | * change its runtime PM status field to RPM_SUSPENDED. Also, if the device's | |
1670 | * usage and children counters don't indicate that the device was in use before | |
1671 | * the system-wide transition under way, decrement its parent's children counter | |
1672 | * (if there is a parent). Keep runtime PM disabled to preserve the state | |
1673 | * unless we encounter errors. | |
37f20416 UH |
1674 | * |
1675 | * Typically this function may be invoked from a system suspend callback to make | |
4918e1f8 RW |
1676 | * sure the device is put into low power state and it should only be used during |
1677 | * system-wide PM transitions to sleep states. It assumes that the analogous | |
1678 | * pm_runtime_force_resume() will be used to resume the device. | |
37f20416 UH |
1679 | */ |
1680 | int pm_runtime_force_suspend(struct device *dev) | |
1681 | { | |
1682 | int (*callback)(struct device *); | |
617fcb67 | 1683 | int ret; |
37f20416 UH |
1684 | |
1685 | pm_runtime_disable(dev); | |
37f20416 UH |
1686 | if (pm_runtime_status_suspended(dev)) |
1687 | return 0; | |
1688 | ||
dbcd2d72 | 1689 | callback = RPM_GET_CALLBACK(dev, runtime_suspend); |
37f20416 | 1690 | |
617fcb67 | 1691 | ret = callback ? callback(dev) : 0; |
37f20416 UH |
1692 | if (ret) |
1693 | goto err; | |
1694 | ||
1d9174fb | 1695 | /* |
4918e1f8 RW |
1696 | * If the device can stay in suspend after the system-wide transition |
1697 | * to the working state that will follow, drop the children counter of | |
1698 | * its parent, but set its status to RPM_SUSPENDED anyway in case this | |
1699 | * function will be called again for it in the meantime. | |
1d9174fb | 1700 | */ |
4918e1f8 RW |
1701 | if (pm_runtime_need_not_resume(dev)) |
1702 | pm_runtime_set_suspended(dev); | |
1703 | else | |
1704 | __update_runtime_status(dev, RPM_SUSPENDED); | |
1d9174fb | 1705 | |
37f20416 | 1706 | return 0; |
4918e1f8 | 1707 | |
37f20416 UH |
1708 | err: |
1709 | pm_runtime_enable(dev); | |
1710 | return ret; | |
1711 | } | |
1712 | EXPORT_SYMBOL_GPL(pm_runtime_force_suspend); | |
1713 | ||
1714 | /** | |
1d9174fb | 1715 | * pm_runtime_force_resume - Force a device into resume state if needed. |
37f20416 UH |
1716 | * @dev: Device to resume. |
1717 | * | |
1718 | * Prior invoking this function we expect the user to have brought the device | |
1719 | * into low power state by a call to pm_runtime_force_suspend(). Here we reverse | |
4918e1f8 RW |
1720 | * those actions and bring the device into full power, if it is expected to be |
1721 | * used on system resume. In the other case, we defer the resume to be managed | |
1722 | * via runtime PM. | |
37f20416 | 1723 | * |
1d9174fb | 1724 | * Typically this function may be invoked from a system resume callback. |
37f20416 UH |
1725 | */ |
1726 | int pm_runtime_force_resume(struct device *dev) | |
1727 | { | |
1728 | int (*callback)(struct device *); | |
1729 | int ret = 0; | |
1730 | ||
4918e1f8 | 1731 | if (!pm_runtime_status_suspended(dev) || pm_runtime_need_not_resume(dev)) |
9f5b5274 UH |
1732 | goto out; |
1733 | ||
1d9174fb | 1734 | /* |
4918e1f8 RW |
1735 | * The value of the parent's children counter is correct already, so |
1736 | * just update the status of the device. | |
1737 | */ | |
1738 | __update_runtime_status(dev, RPM_ACTIVE); | |
1d9174fb | 1739 | |
4918e1f8 | 1740 | callback = RPM_GET_CALLBACK(dev, runtime_resume); |
37f20416 | 1741 | |
617fcb67 | 1742 | ret = callback ? callback(dev) : 0; |
0ae3aeef UH |
1743 | if (ret) { |
1744 | pm_runtime_set_suspended(dev); | |
1745 | goto out; | |
1746 | } | |
1747 | ||
37f20416 UH |
1748 | pm_runtime_mark_last_busy(dev); |
1749 | out: | |
1750 | pm_runtime_enable(dev); | |
1751 | return ret; | |
1752 | } | |
1753 | EXPORT_SYMBOL_GPL(pm_runtime_force_resume); |