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 | { | |
69 | unsigned long now = jiffies; | |
def0c0a3 | 70 | unsigned long delta; |
4769373c AS |
71 | |
72 | delta = now - dev->power.accounting_timestamp; | |
73 | ||
4769373c AS |
74 | dev->power.accounting_timestamp = now; |
75 | ||
76 | if (dev->power.disable_depth > 0) | |
77 | return; | |
78 | ||
79 | if (dev->power.runtime_status == RPM_SUSPENDED) | |
80 | dev->power.suspended_jiffies += delta; | |
81 | else | |
82 | dev->power.active_jiffies += delta; | |
83 | } | |
84 | ||
85 | static void __update_runtime_status(struct device *dev, enum rpm_status status) | |
86 | { | |
87 | update_pm_runtime_accounting(dev); | |
88 | dev->power.runtime_status = status; | |
89 | } | |
90 | ||
5e928f77 RW |
91 | /** |
92 | * pm_runtime_deactivate_timer - Deactivate given device's suspend timer. | |
93 | * @dev: Device to handle. | |
94 | */ | |
95 | static void pm_runtime_deactivate_timer(struct device *dev) | |
96 | { | |
97 | if (dev->power.timer_expires > 0) { | |
74fb4486 | 98 | hrtimer_try_to_cancel(&dev->power.suspend_timer); |
5e928f77 RW |
99 | dev->power.timer_expires = 0; |
100 | } | |
101 | } | |
102 | ||
103 | /** | |
104 | * pm_runtime_cancel_pending - Deactivate suspend timer and cancel requests. | |
105 | * @dev: Device to handle. | |
106 | */ | |
107 | static void pm_runtime_cancel_pending(struct device *dev) | |
108 | { | |
109 | pm_runtime_deactivate_timer(dev); | |
110 | /* | |
111 | * In case there's a request pending, make sure its work function will | |
112 | * return without doing anything. | |
113 | */ | |
114 | dev->power.request = RPM_REQ_NONE; | |
115 | } | |
116 | ||
15bcb91d AS |
117 | /* |
118 | * pm_runtime_autosuspend_expiration - Get a device's autosuspend-delay expiration time. | |
119 | * @dev: Device to handle. | |
120 | * | |
121 | * Compute the autosuspend-delay expiration time based on the device's | |
122 | * power.last_busy time. If the delay has already expired or is disabled | |
123 | * (negative) or the power.use_autosuspend flag isn't set, return 0. | |
1f7b7081 | 124 | * Otherwise return the expiration time in nanoseconds (adjusted to be nonzero). |
15bcb91d AS |
125 | * |
126 | * This function may be called either with or without dev->power.lock held. | |
127 | * Either way it can be racy, since power.last_busy may be updated at any time. | |
128 | */ | |
8234f673 | 129 | u64 pm_runtime_autosuspend_expiration(struct device *dev) |
15bcb91d AS |
130 | { |
131 | int autosuspend_delay; | |
8234f673 | 132 | u64 last_busy, expires = 0; |
15efb47d | 133 | u64 now = ktime_get_mono_fast_ns(); |
15bcb91d AS |
134 | |
135 | if (!dev->power.use_autosuspend) | |
136 | goto out; | |
137 | ||
6aa7de05 | 138 | autosuspend_delay = READ_ONCE(dev->power.autosuspend_delay); |
15bcb91d AS |
139 | if (autosuspend_delay < 0) |
140 | goto out; | |
141 | ||
6aa7de05 | 142 | last_busy = READ_ONCE(dev->power.last_busy); |
15bcb91d | 143 | |
ca27e4cd | 144 | expires = last_busy + (u64)autosuspend_delay * NSEC_PER_MSEC; |
8234f673 | 145 | if (expires <= now) |
15bcb91d AS |
146 | expires = 0; /* Already expired. */ |
147 | ||
148 | out: | |
149 | return expires; | |
150 | } | |
151 | EXPORT_SYMBOL_GPL(pm_runtime_autosuspend_expiration); | |
152 | ||
e823407f ML |
153 | static int dev_memalloc_noio(struct device *dev, void *data) |
154 | { | |
155 | return dev->power.memalloc_noio; | |
156 | } | |
157 | ||
158 | /* | |
159 | * pm_runtime_set_memalloc_noio - Set a device's memalloc_noio flag. | |
160 | * @dev: Device to handle. | |
161 | * @enable: True for setting the flag and False for clearing the flag. | |
162 | * | |
163 | * Set the flag for all devices in the path from the device to the | |
164 | * root device in the device tree if @enable is true, otherwise clear | |
165 | * the flag for devices in the path whose siblings don't set the flag. | |
166 | * | |
167 | * The function should only be called by block device, or network | |
168 | * device driver for solving the deadlock problem during runtime | |
169 | * resume/suspend: | |
170 | * | |
171 | * If memory allocation with GFP_KERNEL is called inside runtime | |
172 | * resume/suspend callback of any one of its ancestors(or the | |
173 | * block device itself), the deadlock may be triggered inside the | |
174 | * memory allocation since it might not complete until the block | |
175 | * device becomes active and the involed page I/O finishes. The | |
176 | * situation is pointed out first by Alan Stern. Network device | |
177 | * are involved in iSCSI kind of situation. | |
178 | * | |
179 | * The lock of dev_hotplug_mutex is held in the function for handling | |
180 | * hotplug race because pm_runtime_set_memalloc_noio() may be called | |
181 | * in async probe(). | |
182 | * | |
183 | * The function should be called between device_add() and device_del() | |
184 | * on the affected device(block/network device). | |
185 | */ | |
186 | void pm_runtime_set_memalloc_noio(struct device *dev, bool enable) | |
187 | { | |
188 | static DEFINE_MUTEX(dev_hotplug_mutex); | |
189 | ||
190 | mutex_lock(&dev_hotplug_mutex); | |
191 | for (;;) { | |
192 | bool enabled; | |
193 | ||
194 | /* hold power lock since bitfield is not SMP-safe. */ | |
195 | spin_lock_irq(&dev->power.lock); | |
196 | enabled = dev->power.memalloc_noio; | |
197 | dev->power.memalloc_noio = enable; | |
198 | spin_unlock_irq(&dev->power.lock); | |
199 | ||
200 | /* | |
201 | * not need to enable ancestors any more if the device | |
202 | * has been enabled. | |
203 | */ | |
204 | if (enabled && enable) | |
205 | break; | |
206 | ||
207 | dev = dev->parent; | |
208 | ||
209 | /* | |
210 | * clear flag of the parent device only if all the | |
211 | * children don't set the flag because ancestor's | |
212 | * flag was set by any one of the descendants. | |
213 | */ | |
214 | if (!dev || (!enable && | |
215 | device_for_each_child(dev, NULL, | |
216 | dev_memalloc_noio))) | |
217 | break; | |
218 | } | |
219 | mutex_unlock(&dev_hotplug_mutex); | |
220 | } | |
221 | EXPORT_SYMBOL_GPL(pm_runtime_set_memalloc_noio); | |
222 | ||
5e928f77 | 223 | /** |
1bfee5bc AS |
224 | * rpm_check_suspend_allowed - Test whether a device may be suspended. |
225 | * @dev: Device to test. | |
5e928f77 | 226 | */ |
1bfee5bc | 227 | static int rpm_check_suspend_allowed(struct device *dev) |
5e928f77 RW |
228 | { |
229 | int retval = 0; | |
230 | ||
5e928f77 RW |
231 | if (dev->power.runtime_error) |
232 | retval = -EINVAL; | |
632e270e RW |
233 | else if (dev->power.disable_depth > 0) |
234 | retval = -EACCES; | |
235 | else if (atomic_read(&dev->power.usage_count) > 0) | |
5e928f77 | 236 | retval = -EAGAIN; |
62006c17 UH |
237 | else if (!dev->power.ignore_children && |
238 | atomic_read(&dev->power.child_count)) | |
5e928f77 | 239 | retval = -EBUSY; |
1bfee5bc AS |
240 | |
241 | /* Pending resume requests take precedence over suspends. */ | |
242 | else if ((dev->power.deferred_resume | |
78ca7c37 | 243 | && dev->power.runtime_status == RPM_SUSPENDING) |
1bfee5bc AS |
244 | || (dev->power.request_pending |
245 | && dev->power.request == RPM_REQ_RESUME)) | |
246 | retval = -EAGAIN; | |
0759e80b | 247 | else if (__dev_pm_qos_read_value(dev) == 0) |
55d7ec45 | 248 | retval = -EPERM; |
1bfee5bc AS |
249 | else if (dev->power.runtime_status == RPM_SUSPENDED) |
250 | retval = 1; | |
251 | ||
252 | return retval; | |
253 | } | |
254 | ||
21d5c57b RW |
255 | static int rpm_get_suppliers(struct device *dev) |
256 | { | |
257 | struct device_link *link; | |
258 | ||
259 | list_for_each_entry_rcu(link, &dev->links.suppliers, c_node) { | |
260 | int retval; | |
261 | ||
262 | if (!(link->flags & DL_FLAG_PM_RUNTIME)) | |
263 | continue; | |
264 | ||
265 | if (READ_ONCE(link->status) == DL_STATE_SUPPLIER_UNBIND || | |
266 | link->rpm_active) | |
267 | continue; | |
268 | ||
269 | retval = pm_runtime_get_sync(link->supplier); | |
31eb7431 RW |
270 | /* Ignore suppliers with disabled runtime PM. */ |
271 | if (retval < 0 && retval != -EACCES) { | |
21d5c57b RW |
272 | pm_runtime_put_noidle(link->supplier); |
273 | return retval; | |
274 | } | |
275 | link->rpm_active = true; | |
276 | } | |
277 | return 0; | |
278 | } | |
279 | ||
280 | static void rpm_put_suppliers(struct device *dev) | |
281 | { | |
282 | struct device_link *link; | |
283 | ||
284 | list_for_each_entry_rcu(link, &dev->links.suppliers, c_node) | |
285 | if (link->rpm_active && | |
286 | READ_ONCE(link->status) != DL_STATE_SUPPLIER_UNBIND) { | |
287 | pm_runtime_put(link->supplier); | |
288 | link->rpm_active = false; | |
289 | } | |
290 | } | |
291 | ||
ad3c36a5 RW |
292 | /** |
293 | * __rpm_callback - Run a given runtime PM callback for a given device. | |
294 | * @cb: Runtime PM callback to run. | |
295 | * @dev: Device to run the callback for. | |
296 | */ | |
297 | static int __rpm_callback(int (*cb)(struct device *), struct device *dev) | |
298 | __releases(&dev->power.lock) __acquires(&dev->power.lock) | |
299 | { | |
21d5c57b | 300 | int retval, idx; |
baa8809f | 301 | bool use_links = dev->power.links_count > 0; |
ad3c36a5 | 302 | |
21d5c57b | 303 | if (dev->power.irq_safe) { |
ad3c36a5 | 304 | spin_unlock(&dev->power.lock); |
21d5c57b | 305 | } else { |
ad3c36a5 RW |
306 | spin_unlock_irq(&dev->power.lock); |
307 | ||
21d5c57b RW |
308 | /* |
309 | * Resume suppliers if necessary. | |
310 | * | |
311 | * The device's runtime PM status cannot change until this | |
312 | * routine returns, so it is safe to read the status outside of | |
313 | * the lock. | |
314 | */ | |
baa8809f | 315 | if (use_links && dev->power.runtime_status == RPM_RESUMING) { |
21d5c57b RW |
316 | idx = device_links_read_lock(); |
317 | ||
318 | retval = rpm_get_suppliers(dev); | |
319 | if (retval) | |
320 | goto fail; | |
321 | ||
322 | device_links_read_unlock(idx); | |
323 | } | |
324 | } | |
325 | ||
ad3c36a5 RW |
326 | retval = cb(dev); |
327 | ||
21d5c57b | 328 | if (dev->power.irq_safe) { |
ad3c36a5 | 329 | spin_lock(&dev->power.lock); |
21d5c57b RW |
330 | } else { |
331 | /* | |
332 | * If the device is suspending and the callback has returned | |
333 | * success, drop the usage counters of the suppliers that have | |
334 | * been reference counted on its resume. | |
335 | * | |
336 | * Do that if resume fails too. | |
337 | */ | |
baa8809f RW |
338 | if (use_links |
339 | && ((dev->power.runtime_status == RPM_SUSPENDING && !retval) | |
340 | || (dev->power.runtime_status == RPM_RESUMING && retval))) { | |
21d5c57b RW |
341 | idx = device_links_read_lock(); |
342 | ||
343 | fail: | |
344 | rpm_put_suppliers(dev); | |
345 | ||
346 | device_links_read_unlock(idx); | |
347 | } | |
348 | ||
ad3c36a5 | 349 | spin_lock_irq(&dev->power.lock); |
21d5c57b | 350 | } |
ad3c36a5 RW |
351 | |
352 | return retval; | |
353 | } | |
354 | ||
1bfee5bc | 355 | /** |
140a6c94 | 356 | * rpm_idle - Notify device bus type if the device can be suspended. |
1bfee5bc AS |
357 | * @dev: Device to notify the bus type about. |
358 | * @rpmflags: Flag bits. | |
359 | * | |
62052ab1 | 360 | * Check if the device's runtime PM status allows it to be suspended. If |
1bfee5bc AS |
361 | * another idle notification has been started earlier, return immediately. If |
362 | * the RPM_ASYNC flag is set then queue an idle-notification request; otherwise | |
d66e6db2 UH |
363 | * run the ->runtime_idle() callback directly. If the ->runtime_idle callback |
364 | * doesn't exist or if it returns 0, call rpm_suspend with the RPM_AUTO flag. | |
1bfee5bc AS |
365 | * |
366 | * This function must be called under dev->power.lock with interrupts disabled. | |
367 | */ | |
140a6c94 | 368 | static int rpm_idle(struct device *dev, int rpmflags) |
1bfee5bc | 369 | { |
71c63122 | 370 | int (*callback)(struct device *); |
1bfee5bc AS |
371 | int retval; |
372 | ||
d7737ce9 | 373 | trace_rpm_idle_rcuidle(dev, rpmflags); |
1bfee5bc AS |
374 | retval = rpm_check_suspend_allowed(dev); |
375 | if (retval < 0) | |
376 | ; /* Conditions are wrong. */ | |
377 | ||
378 | /* Idle notifications are allowed only in the RPM_ACTIVE state. */ | |
379 | else if (dev->power.runtime_status != RPM_ACTIVE) | |
380 | retval = -EAGAIN; | |
381 | ||
382 | /* | |
383 | * Any pending request other than an idle notification takes | |
384 | * precedence over us, except that the timer may be running. | |
385 | */ | |
386 | else if (dev->power.request_pending && | |
387 | dev->power.request > RPM_REQ_IDLE) | |
388 | retval = -EAGAIN; | |
389 | ||
390 | /* Act as though RPM_NOWAIT is always set. */ | |
391 | else if (dev->power.idle_notification) | |
392 | retval = -EINPROGRESS; | |
5e928f77 RW |
393 | if (retval) |
394 | goto out; | |
395 | ||
1bfee5bc AS |
396 | /* Pending requests need to be canceled. */ |
397 | dev->power.request = RPM_REQ_NONE; | |
398 | ||
45f0a85c | 399 | if (dev->power.no_callbacks) |
7490e442 | 400 | goto out; |
7490e442 | 401 | |
1bfee5bc AS |
402 | /* Carry out an asynchronous or a synchronous idle notification. */ |
403 | if (rpmflags & RPM_ASYNC) { | |
404 | dev->power.request = RPM_REQ_IDLE; | |
405 | if (!dev->power.request_pending) { | |
406 | dev->power.request_pending = true; | |
407 | queue_work(pm_wq, &dev->power.work); | |
5e928f77 | 408 | } |
d7737ce9 | 409 | trace_rpm_return_int_rcuidle(dev, _THIS_IP_, 0); |
45f0a85c | 410 | return 0; |
5e928f77 RW |
411 | } |
412 | ||
413 | dev->power.idle_notification = true; | |
414 | ||
dbcd2d72 | 415 | callback = RPM_GET_CALLBACK(dev, runtime_idle); |
35cd133c | 416 | |
ad3c36a5 | 417 | if (callback) |
45f0a85c | 418 | retval = __rpm_callback(callback, dev); |
5e928f77 RW |
419 | |
420 | dev->power.idle_notification = false; | |
421 | wake_up_all(&dev->power.wait_queue); | |
422 | ||
423 | out: | |
d7737ce9 | 424 | trace_rpm_return_int_rcuidle(dev, _THIS_IP_, retval); |
d66e6db2 | 425 | return retval ? retval : rpm_suspend(dev, rpmflags | RPM_AUTO); |
5e928f77 RW |
426 | } |
427 | ||
71c63122 RW |
428 | /** |
429 | * rpm_callback - Run a given runtime PM callback for a given device. | |
430 | * @cb: Runtime PM callback to run. | |
431 | * @dev: Device to run the callback for. | |
432 | */ | |
433 | static int rpm_callback(int (*cb)(struct device *), struct device *dev) | |
71c63122 RW |
434 | { |
435 | int retval; | |
436 | ||
437 | if (!cb) | |
438 | return -ENOSYS; | |
439 | ||
db88175f ML |
440 | if (dev->power.memalloc_noio) { |
441 | unsigned int noio_flag; | |
442 | ||
443 | /* | |
444 | * Deadlock might be caused if memory allocation with | |
445 | * GFP_KERNEL happens inside runtime_suspend and | |
446 | * runtime_resume callbacks of one block device's | |
447 | * ancestor or the block device itself. Network | |
448 | * device might be thought as part of iSCSI block | |
449 | * device, so network device and its ancestor should | |
450 | * be marked as memalloc_noio too. | |
451 | */ | |
452 | noio_flag = memalloc_noio_save(); | |
453 | retval = __rpm_callback(cb, dev); | |
454 | memalloc_noio_restore(noio_flag); | |
455 | } else { | |
456 | retval = __rpm_callback(cb, dev); | |
457 | } | |
71c63122 | 458 | |
71c63122 | 459 | dev->power.runtime_error = retval; |
632e270e | 460 | return retval != -EACCES ? retval : -EIO; |
71c63122 RW |
461 | } |
462 | ||
5e928f77 | 463 | /** |
62052ab1 | 464 | * rpm_suspend - Carry out runtime suspend of given device. |
5e928f77 | 465 | * @dev: Device to suspend. |
3f9af051 | 466 | * @rpmflags: Flag bits. |
5e928f77 | 467 | * |
47d8f0ba ML |
468 | * Check if the device's runtime PM status allows it to be suspended. |
469 | * Cancel a pending idle notification, autosuspend or suspend. If | |
470 | * another suspend has been started earlier, either return immediately | |
471 | * or wait for it to finish, depending on the RPM_NOWAIT and RPM_ASYNC | |
472 | * flags. If the RPM_ASYNC flag is set then queue a suspend request; | |
857b36c7 ML |
473 | * otherwise run the ->runtime_suspend() callback directly. When |
474 | * ->runtime_suspend succeeded, if a deferred resume was requested while | |
475 | * the callback was running then carry it out, otherwise send an idle | |
476 | * notification for its parent (if the suspend succeeded and both | |
477 | * ignore_children of parent->power and irq_safe of dev->power are not set). | |
886486b7 AS |
478 | * If ->runtime_suspend failed with -EAGAIN or -EBUSY, and if the RPM_AUTO |
479 | * flag is set and the next autosuspend-delay expiration time is in the | |
480 | * future, schedule another autosuspend attempt. | |
5e928f77 RW |
481 | * |
482 | * This function must be called under dev->power.lock with interrupts disabled. | |
483 | */ | |
140a6c94 | 484 | static int rpm_suspend(struct device *dev, int rpmflags) |
5e928f77 RW |
485 | __releases(&dev->power.lock) __acquires(&dev->power.lock) |
486 | { | |
71c63122 | 487 | int (*callback)(struct device *); |
5e928f77 | 488 | struct device *parent = NULL; |
1bfee5bc | 489 | int retval; |
5e928f77 | 490 | |
77893577 | 491 | trace_rpm_suspend_rcuidle(dev, rpmflags); |
5e928f77 RW |
492 | |
493 | repeat: | |
1bfee5bc | 494 | retval = rpm_check_suspend_allowed(dev); |
5e928f77 | 495 | |
1bfee5bc AS |
496 | if (retval < 0) |
497 | ; /* Conditions are wrong. */ | |
498 | ||
499 | /* Synchronous suspends are not allowed in the RPM_RESUMING state. */ | |
500 | else if (dev->power.runtime_status == RPM_RESUMING && | |
501 | !(rpmflags & RPM_ASYNC)) | |
5e928f77 | 502 | retval = -EAGAIN; |
1bfee5bc | 503 | if (retval) |
5e928f77 | 504 | goto out; |
5e928f77 | 505 | |
15bcb91d AS |
506 | /* If the autosuspend_delay time hasn't expired yet, reschedule. */ |
507 | if ((rpmflags & RPM_AUTO) | |
508 | && dev->power.runtime_status != RPM_SUSPENDING) { | |
8234f673 | 509 | u64 expires = pm_runtime_autosuspend_expiration(dev); |
15bcb91d AS |
510 | |
511 | if (expires != 0) { | |
512 | /* Pending requests need to be canceled. */ | |
513 | dev->power.request = RPM_REQ_NONE; | |
514 | ||
515 | /* | |
516 | * Optimization: If the timer is already running and is | |
517 | * set to expire at or before the autosuspend delay, | |
518 | * avoid the overhead of resetting it. Just let it | |
519 | * expire; pm_suspend_timer_fn() will take care of the | |
520 | * rest. | |
521 | */ | |
8234f673 VG |
522 | if (!(dev->power.timer_expires && |
523 | dev->power.timer_expires <= expires)) { | |
524 | /* | |
525 | * We add a slack of 25% to gather wakeups | |
526 | * without sacrificing the granularity. | |
527 | */ | |
ca27e4cd | 528 | u64 slack = (u64)READ_ONCE(dev->power.autosuspend_delay) * |
8234f673 VG |
529 | (NSEC_PER_MSEC >> 2); |
530 | ||
15bcb91d | 531 | dev->power.timer_expires = expires; |
8234f673 VG |
532 | hrtimer_start_range_ns(&dev->power.suspend_timer, |
533 | ns_to_ktime(expires), | |
534 | slack, | |
535 | HRTIMER_MODE_ABS); | |
15bcb91d AS |
536 | } |
537 | dev->power.timer_autosuspends = 1; | |
538 | goto out; | |
539 | } | |
540 | } | |
541 | ||
5e928f77 RW |
542 | /* Other scheduled or pending requests need to be canceled. */ |
543 | pm_runtime_cancel_pending(dev); | |
544 | ||
5e928f77 RW |
545 | if (dev->power.runtime_status == RPM_SUSPENDING) { |
546 | DEFINE_WAIT(wait); | |
547 | ||
1bfee5bc | 548 | if (rpmflags & (RPM_ASYNC | RPM_NOWAIT)) { |
5e928f77 RW |
549 | retval = -EINPROGRESS; |
550 | goto out; | |
551 | } | |
552 | ||
ad3c36a5 RW |
553 | if (dev->power.irq_safe) { |
554 | spin_unlock(&dev->power.lock); | |
555 | ||
556 | cpu_relax(); | |
557 | ||
558 | spin_lock(&dev->power.lock); | |
559 | goto repeat; | |
560 | } | |
561 | ||
5e928f77 RW |
562 | /* Wait for the other suspend running in parallel with us. */ |
563 | for (;;) { | |
564 | prepare_to_wait(&dev->power.wait_queue, &wait, | |
565 | TASK_UNINTERRUPTIBLE); | |
566 | if (dev->power.runtime_status != RPM_SUSPENDING) | |
567 | break; | |
568 | ||
569 | spin_unlock_irq(&dev->power.lock); | |
570 | ||
571 | schedule(); | |
572 | ||
573 | spin_lock_irq(&dev->power.lock); | |
574 | } | |
575 | finish_wait(&dev->power.wait_queue, &wait); | |
576 | goto repeat; | |
577 | } | |
578 | ||
7490e442 AS |
579 | if (dev->power.no_callbacks) |
580 | goto no_callback; /* Assume success. */ | |
581 | ||
1bfee5bc AS |
582 | /* Carry out an asynchronous or a synchronous suspend. */ |
583 | if (rpmflags & RPM_ASYNC) { | |
15bcb91d AS |
584 | dev->power.request = (rpmflags & RPM_AUTO) ? |
585 | RPM_REQ_AUTOSUSPEND : RPM_REQ_SUSPEND; | |
1bfee5bc AS |
586 | if (!dev->power.request_pending) { |
587 | dev->power.request_pending = true; | |
588 | queue_work(pm_wq, &dev->power.work); | |
589 | } | |
590 | goto out; | |
591 | } | |
592 | ||
8d4b9d1b | 593 | __update_runtime_status(dev, RPM_SUSPENDING); |
5e928f77 | 594 | |
dbcd2d72 | 595 | callback = RPM_GET_CALLBACK(dev, runtime_suspend); |
35cd133c | 596 | |
bed57030 | 597 | dev_pm_enable_wake_irq_check(dev, true); |
71c63122 | 598 | retval = rpm_callback(callback, dev); |
00dc9ad1 RW |
599 | if (retval) |
600 | goto fail; | |
886486b7 | 601 | |
7490e442 | 602 | no_callback: |
857b36c7 ML |
603 | __update_runtime_status(dev, RPM_SUSPENDED); |
604 | pm_runtime_deactivate_timer(dev); | |
5e928f77 | 605 | |
857b36c7 ML |
606 | if (dev->parent) { |
607 | parent = dev->parent; | |
608 | atomic_add_unless(&parent->power.child_count, -1, 0); | |
5e928f77 RW |
609 | } |
610 | wake_up_all(&dev->power.wait_queue); | |
611 | ||
612 | if (dev->power.deferred_resume) { | |
58a34de7 | 613 | dev->power.deferred_resume = false; |
140a6c94 | 614 | rpm_resume(dev, 0); |
5e928f77 RW |
615 | retval = -EAGAIN; |
616 | goto out; | |
617 | } | |
618 | ||
c3810c88 | 619 | /* Maybe the parent is now able to suspend. */ |
c7b61de5 | 620 | if (parent && !parent->power.ignore_children && !dev->power.irq_safe) { |
c3810c88 | 621 | spin_unlock(&dev->power.lock); |
5e928f77 | 622 | |
c3810c88 AS |
623 | spin_lock(&parent->power.lock); |
624 | rpm_idle(parent, RPM_ASYNC); | |
625 | spin_unlock(&parent->power.lock); | |
5e928f77 | 626 | |
c3810c88 | 627 | spin_lock(&dev->power.lock); |
5e928f77 RW |
628 | } |
629 | ||
630 | out: | |
77893577 | 631 | trace_rpm_return_int_rcuidle(dev, _THIS_IP_, retval); |
5e928f77 RW |
632 | |
633 | return retval; | |
00dc9ad1 RW |
634 | |
635 | fail: | |
bed57030 | 636 | dev_pm_disable_wake_irq_check(dev); |
00dc9ad1 | 637 | __update_runtime_status(dev, RPM_ACTIVE); |
00dc9ad1 | 638 | dev->power.deferred_resume = false; |
f2791d73 AS |
639 | wake_up_all(&dev->power.wait_queue); |
640 | ||
00dc9ad1 RW |
641 | if (retval == -EAGAIN || retval == -EBUSY) { |
642 | dev->power.runtime_error = 0; | |
643 | ||
644 | /* | |
645 | * If the callback routine failed an autosuspend, and | |
646 | * if the last_busy time has been updated so that there | |
647 | * is a new autosuspend expiration time, automatically | |
648 | * reschedule another autosuspend. | |
649 | */ | |
650 | if ((rpmflags & RPM_AUTO) && | |
651 | pm_runtime_autosuspend_expiration(dev) != 0) | |
652 | goto repeat; | |
653 | } else { | |
654 | pm_runtime_cancel_pending(dev); | |
655 | } | |
00dc9ad1 | 656 | goto out; |
5e928f77 RW |
657 | } |
658 | ||
659 | /** | |
62052ab1 | 660 | * rpm_resume - Carry out runtime resume of given device. |
5e928f77 | 661 | * @dev: Device to resume. |
3f9af051 | 662 | * @rpmflags: Flag bits. |
5e928f77 | 663 | * |
62052ab1 | 664 | * Check if the device's runtime PM status allows it to be resumed. Cancel |
1bfee5bc | 665 | * any scheduled or pending requests. If another resume has been started |
25985edc | 666 | * earlier, either return immediately or wait for it to finish, depending on the |
1bfee5bc AS |
667 | * RPM_NOWAIT and RPM_ASYNC flags. Similarly, if there's a suspend running in |
668 | * parallel with this function, either tell the other process to resume after | |
669 | * suspending (deferred_resume) or wait for it to finish. If the RPM_ASYNC | |
670 | * flag is set then queue a resume request; otherwise run the | |
671 | * ->runtime_resume() callback directly. Queue an idle notification for the | |
672 | * device if the resume succeeded. | |
5e928f77 RW |
673 | * |
674 | * This function must be called under dev->power.lock with interrupts disabled. | |
675 | */ | |
140a6c94 | 676 | static int rpm_resume(struct device *dev, int rpmflags) |
5e928f77 RW |
677 | __releases(&dev->power.lock) __acquires(&dev->power.lock) |
678 | { | |
71c63122 | 679 | int (*callback)(struct device *); |
5e928f77 RW |
680 | struct device *parent = NULL; |
681 | int retval = 0; | |
682 | ||
d44c950e | 683 | trace_rpm_resume_rcuidle(dev, rpmflags); |
5e928f77 RW |
684 | |
685 | repeat: | |
1bfee5bc | 686 | if (dev->power.runtime_error) |
5e928f77 | 687 | retval = -EINVAL; |
6f3c77b0 KH |
688 | else if (dev->power.disable_depth == 1 && dev->power.is_suspended |
689 | && dev->power.runtime_status == RPM_ACTIVE) | |
690 | retval = 1; | |
1bfee5bc | 691 | else if (dev->power.disable_depth > 0) |
632e270e | 692 | retval = -EACCES; |
1bfee5bc | 693 | if (retval) |
5e928f77 | 694 | goto out; |
5e928f77 | 695 | |
15bcb91d AS |
696 | /* |
697 | * Other scheduled or pending requests need to be canceled. Small | |
698 | * optimization: If an autosuspend timer is running, leave it running | |
699 | * rather than cancelling it now only to restart it again in the near | |
700 | * future. | |
701 | */ | |
702 | dev->power.request = RPM_REQ_NONE; | |
703 | if (!dev->power.timer_autosuspends) | |
704 | pm_runtime_deactivate_timer(dev); | |
5e928f77 | 705 | |
1bfee5bc | 706 | if (dev->power.runtime_status == RPM_ACTIVE) { |
5e928f77 | 707 | retval = 1; |
5e928f77 | 708 | goto out; |
1bfee5bc | 709 | } |
5e928f77 RW |
710 | |
711 | if (dev->power.runtime_status == RPM_RESUMING | |
712 | || dev->power.runtime_status == RPM_SUSPENDING) { | |
713 | DEFINE_WAIT(wait); | |
714 | ||
1bfee5bc | 715 | if (rpmflags & (RPM_ASYNC | RPM_NOWAIT)) { |
5e928f77 RW |
716 | if (dev->power.runtime_status == RPM_SUSPENDING) |
717 | dev->power.deferred_resume = true; | |
1bfee5bc AS |
718 | else |
719 | retval = -EINPROGRESS; | |
5e928f77 RW |
720 | goto out; |
721 | } | |
722 | ||
ad3c36a5 RW |
723 | if (dev->power.irq_safe) { |
724 | spin_unlock(&dev->power.lock); | |
725 | ||
726 | cpu_relax(); | |
727 | ||
728 | spin_lock(&dev->power.lock); | |
729 | goto repeat; | |
730 | } | |
731 | ||
5e928f77 RW |
732 | /* Wait for the operation carried out in parallel with us. */ |
733 | for (;;) { | |
734 | prepare_to_wait(&dev->power.wait_queue, &wait, | |
735 | TASK_UNINTERRUPTIBLE); | |
736 | if (dev->power.runtime_status != RPM_RESUMING | |
737 | && dev->power.runtime_status != RPM_SUSPENDING) | |
738 | break; | |
739 | ||
740 | spin_unlock_irq(&dev->power.lock); | |
741 | ||
742 | schedule(); | |
743 | ||
744 | spin_lock_irq(&dev->power.lock); | |
745 | } | |
746 | finish_wait(&dev->power.wait_queue, &wait); | |
747 | goto repeat; | |
748 | } | |
749 | ||
7490e442 AS |
750 | /* |
751 | * See if we can skip waking up the parent. This is safe only if | |
752 | * power.no_callbacks is set, because otherwise we don't know whether | |
753 | * the resume will actually succeed. | |
754 | */ | |
755 | if (dev->power.no_callbacks && !parent && dev->parent) { | |
d63be5f9 | 756 | spin_lock_nested(&dev->parent->power.lock, SINGLE_DEPTH_NESTING); |
7490e442 AS |
757 | if (dev->parent->power.disable_depth > 0 |
758 | || dev->parent->power.ignore_children | |
759 | || dev->parent->power.runtime_status == RPM_ACTIVE) { | |
760 | atomic_inc(&dev->parent->power.child_count); | |
761 | spin_unlock(&dev->parent->power.lock); | |
7f321c26 | 762 | retval = 1; |
7490e442 AS |
763 | goto no_callback; /* Assume success. */ |
764 | } | |
765 | spin_unlock(&dev->parent->power.lock); | |
766 | } | |
767 | ||
1bfee5bc AS |
768 | /* Carry out an asynchronous or a synchronous resume. */ |
769 | if (rpmflags & RPM_ASYNC) { | |
770 | dev->power.request = RPM_REQ_RESUME; | |
771 | if (!dev->power.request_pending) { | |
772 | dev->power.request_pending = true; | |
773 | queue_work(pm_wq, &dev->power.work); | |
774 | } | |
775 | retval = 0; | |
776 | goto out; | |
777 | } | |
778 | ||
5e928f77 RW |
779 | if (!parent && dev->parent) { |
780 | /* | |
c7b61de5 AS |
781 | * Increment the parent's usage counter and resume it if |
782 | * necessary. Not needed if dev is irq-safe; then the | |
783 | * parent is permanently resumed. | |
5e928f77 RW |
784 | */ |
785 | parent = dev->parent; | |
c7b61de5 AS |
786 | if (dev->power.irq_safe) |
787 | goto skip_parent; | |
862f89b3 | 788 | spin_unlock(&dev->power.lock); |
5e928f77 RW |
789 | |
790 | pm_runtime_get_noresume(parent); | |
791 | ||
862f89b3 | 792 | spin_lock(&parent->power.lock); |
5e928f77 | 793 | /* |
216ef0b6 UH |
794 | * Resume the parent if it has runtime PM enabled and not been |
795 | * set to ignore its children. | |
5e928f77 RW |
796 | */ |
797 | if (!parent->power.disable_depth | |
798 | && !parent->power.ignore_children) { | |
140a6c94 | 799 | rpm_resume(parent, 0); |
5e928f77 RW |
800 | if (parent->power.runtime_status != RPM_ACTIVE) |
801 | retval = -EBUSY; | |
802 | } | |
862f89b3 | 803 | spin_unlock(&parent->power.lock); |
5e928f77 | 804 | |
862f89b3 | 805 | spin_lock(&dev->power.lock); |
5e928f77 RW |
806 | if (retval) |
807 | goto out; | |
808 | goto repeat; | |
809 | } | |
c7b61de5 | 810 | skip_parent: |
5e928f77 | 811 | |
7490e442 AS |
812 | if (dev->power.no_callbacks) |
813 | goto no_callback; /* Assume success. */ | |
814 | ||
8d4b9d1b | 815 | __update_runtime_status(dev, RPM_RESUMING); |
5e928f77 | 816 | |
dbcd2d72 | 817 | callback = RPM_GET_CALLBACK(dev, runtime_resume); |
35cd133c | 818 | |
bed57030 | 819 | dev_pm_disable_wake_irq_check(dev); |
71c63122 | 820 | retval = rpm_callback(callback, dev); |
5e928f77 | 821 | if (retval) { |
8d4b9d1b | 822 | __update_runtime_status(dev, RPM_SUSPENDED); |
5e928f77 | 823 | pm_runtime_cancel_pending(dev); |
bed57030 | 824 | dev_pm_enable_wake_irq_check(dev, false); |
5e928f77 | 825 | } else { |
7490e442 | 826 | no_callback: |
8d4b9d1b | 827 | __update_runtime_status(dev, RPM_ACTIVE); |
56f487c7 | 828 | pm_runtime_mark_last_busy(dev); |
5e928f77 RW |
829 | if (parent) |
830 | atomic_inc(&parent->power.child_count); | |
831 | } | |
832 | wake_up_all(&dev->power.wait_queue); | |
833 | ||
7f321c26 | 834 | if (retval >= 0) |
140a6c94 | 835 | rpm_idle(dev, RPM_ASYNC); |
5e928f77 RW |
836 | |
837 | out: | |
c7b61de5 | 838 | if (parent && !dev->power.irq_safe) { |
5e928f77 RW |
839 | spin_unlock_irq(&dev->power.lock); |
840 | ||
841 | pm_runtime_put(parent); | |
842 | ||
843 | spin_lock_irq(&dev->power.lock); | |
844 | } | |
845 | ||
d44c950e | 846 | trace_rpm_return_int_rcuidle(dev, _THIS_IP_, retval); |
5e928f77 RW |
847 | |
848 | return retval; | |
849 | } | |
850 | ||
5e928f77 | 851 | /** |
62052ab1 | 852 | * pm_runtime_work - Universal runtime PM work function. |
5e928f77 RW |
853 | * @work: Work structure used for scheduling the execution of this function. |
854 | * | |
855 | * Use @work to get the device object the work is to be done for, determine what | |
62052ab1 | 856 | * is to be done and execute the appropriate runtime PM function. |
5e928f77 RW |
857 | */ |
858 | static void pm_runtime_work(struct work_struct *work) | |
859 | { | |
860 | struct device *dev = container_of(work, struct device, power.work); | |
861 | enum rpm_request req; | |
862 | ||
863 | spin_lock_irq(&dev->power.lock); | |
864 | ||
865 | if (!dev->power.request_pending) | |
866 | goto out; | |
867 | ||
868 | req = dev->power.request; | |
869 | dev->power.request = RPM_REQ_NONE; | |
870 | dev->power.request_pending = false; | |
871 | ||
872 | switch (req) { | |
873 | case RPM_REQ_NONE: | |
874 | break; | |
875 | case RPM_REQ_IDLE: | |
140a6c94 | 876 | rpm_idle(dev, RPM_NOWAIT); |
5e928f77 RW |
877 | break; |
878 | case RPM_REQ_SUSPEND: | |
140a6c94 | 879 | rpm_suspend(dev, RPM_NOWAIT); |
5e928f77 | 880 | break; |
15bcb91d AS |
881 | case RPM_REQ_AUTOSUSPEND: |
882 | rpm_suspend(dev, RPM_NOWAIT | RPM_AUTO); | |
883 | break; | |
5e928f77 | 884 | case RPM_REQ_RESUME: |
140a6c94 | 885 | rpm_resume(dev, RPM_NOWAIT); |
5e928f77 RW |
886 | break; |
887 | } | |
888 | ||
889 | out: | |
890 | spin_unlock_irq(&dev->power.lock); | |
891 | } | |
892 | ||
5e928f77 RW |
893 | /** |
894 | * pm_suspend_timer_fn - Timer function for pm_schedule_suspend(). | |
895 | * @data: Device pointer passed by pm_schedule_suspend(). | |
896 | * | |
1bfee5bc | 897 | * Check if the time is right and queue a suspend request. |
5e928f77 | 898 | */ |
8234f673 | 899 | static enum hrtimer_restart pm_suspend_timer_fn(struct hrtimer *timer) |
5e928f77 | 900 | { |
8234f673 | 901 | struct device *dev = container_of(timer, struct device, power.suspend_timer); |
5e928f77 | 902 | unsigned long flags; |
8234f673 | 903 | u64 expires; |
5e928f77 RW |
904 | |
905 | spin_lock_irqsave(&dev->power.lock, flags); | |
906 | ||
907 | expires = dev->power.timer_expires; | |
1f7b7081 LM |
908 | /* |
909 | * If 'expires' is after the current time, we've been called | |
910 | * too early. | |
911 | */ | |
15efb47d | 912 | if (expires > 0 && expires < ktime_get_mono_fast_ns()) { |
5e928f77 | 913 | dev->power.timer_expires = 0; |
15bcb91d AS |
914 | rpm_suspend(dev, dev->power.timer_autosuspends ? |
915 | (RPM_ASYNC | RPM_AUTO) : RPM_ASYNC); | |
5e928f77 RW |
916 | } |
917 | ||
918 | spin_unlock_irqrestore(&dev->power.lock, flags); | |
8234f673 VG |
919 | |
920 | return HRTIMER_NORESTART; | |
5e928f77 RW |
921 | } |
922 | ||
923 | /** | |
924 | * pm_schedule_suspend - Set up a timer to submit a suspend request in future. | |
925 | * @dev: Device to suspend. | |
926 | * @delay: Time to wait before submitting a suspend request, in milliseconds. | |
927 | */ | |
928 | int pm_schedule_suspend(struct device *dev, unsigned int delay) | |
929 | { | |
930 | unsigned long flags; | |
15efb47d | 931 | u64 expires; |
1bfee5bc | 932 | int retval; |
5e928f77 RW |
933 | |
934 | spin_lock_irqsave(&dev->power.lock, flags); | |
935 | ||
5e928f77 | 936 | if (!delay) { |
140a6c94 | 937 | retval = rpm_suspend(dev, RPM_ASYNC); |
5e928f77 RW |
938 | goto out; |
939 | } | |
940 | ||
1bfee5bc | 941 | retval = rpm_check_suspend_allowed(dev); |
5e928f77 RW |
942 | if (retval) |
943 | goto out; | |
944 | ||
1bfee5bc AS |
945 | /* Other scheduled or pending requests need to be canceled. */ |
946 | pm_runtime_cancel_pending(dev); | |
947 | ||
15efb47d VG |
948 | expires = ktime_get_mono_fast_ns() + (u64)delay * NSEC_PER_MSEC; |
949 | dev->power.timer_expires = expires; | |
15bcb91d | 950 | dev->power.timer_autosuspends = 0; |
8234f673 | 951 | hrtimer_start(&dev->power.suspend_timer, expires, HRTIMER_MODE_ABS); |
5e928f77 RW |
952 | |
953 | out: | |
954 | spin_unlock_irqrestore(&dev->power.lock, flags); | |
955 | ||
956 | return retval; | |
957 | } | |
958 | EXPORT_SYMBOL_GPL(pm_schedule_suspend); | |
959 | ||
5e928f77 | 960 | /** |
62052ab1 | 961 | * __pm_runtime_idle - Entry point for runtime idle operations. |
140a6c94 AS |
962 | * @dev: Device to send idle notification for. |
963 | * @rpmflags: Flag bits. | |
964 | * | |
965 | * If the RPM_GET_PUT flag is set, decrement the device's usage count and | |
966 | * return immediately if it is larger than zero. Then carry out an idle | |
967 | * notification, either synchronous or asynchronous. | |
968 | * | |
311aab73 CC |
969 | * This routine may be called in atomic context if the RPM_ASYNC flag is set, |
970 | * or if pm_runtime_irq_safe() has been called. | |
5e928f77 | 971 | */ |
140a6c94 | 972 | int __pm_runtime_idle(struct device *dev, int rpmflags) |
5e928f77 RW |
973 | { |
974 | unsigned long flags; | |
975 | int retval; | |
976 | ||
140a6c94 AS |
977 | if (rpmflags & RPM_GET_PUT) { |
978 | if (!atomic_dec_and_test(&dev->power.usage_count)) | |
979 | return 0; | |
980 | } | |
981 | ||
a9306a63 RW |
982 | might_sleep_if(!(rpmflags & RPM_ASYNC) && !dev->power.irq_safe); |
983 | ||
5e928f77 | 984 | spin_lock_irqsave(&dev->power.lock, flags); |
140a6c94 | 985 | retval = rpm_idle(dev, rpmflags); |
5e928f77 RW |
986 | spin_unlock_irqrestore(&dev->power.lock, flags); |
987 | ||
988 | return retval; | |
989 | } | |
140a6c94 | 990 | EXPORT_SYMBOL_GPL(__pm_runtime_idle); |
5e928f77 RW |
991 | |
992 | /** | |
62052ab1 | 993 | * __pm_runtime_suspend - Entry point for runtime put/suspend operations. |
140a6c94 | 994 | * @dev: Device to suspend. |
3f9af051 | 995 | * @rpmflags: Flag bits. |
5e928f77 | 996 | * |
15bcb91d AS |
997 | * If the RPM_GET_PUT flag is set, decrement the device's usage count and |
998 | * return immediately if it is larger than zero. Then carry out a suspend, | |
999 | * either synchronous or asynchronous. | |
140a6c94 | 1000 | * |
311aab73 CC |
1001 | * This routine may be called in atomic context if the RPM_ASYNC flag is set, |
1002 | * or if pm_runtime_irq_safe() has been called. | |
5e928f77 | 1003 | */ |
140a6c94 | 1004 | int __pm_runtime_suspend(struct device *dev, int rpmflags) |
5e928f77 | 1005 | { |
140a6c94 | 1006 | unsigned long flags; |
1d531c14 | 1007 | int retval; |
5e928f77 | 1008 | |
15bcb91d AS |
1009 | if (rpmflags & RPM_GET_PUT) { |
1010 | if (!atomic_dec_and_test(&dev->power.usage_count)) | |
1011 | return 0; | |
1012 | } | |
1013 | ||
a9306a63 RW |
1014 | might_sleep_if(!(rpmflags & RPM_ASYNC) && !dev->power.irq_safe); |
1015 | ||
140a6c94 AS |
1016 | spin_lock_irqsave(&dev->power.lock, flags); |
1017 | retval = rpm_suspend(dev, rpmflags); | |
1018 | spin_unlock_irqrestore(&dev->power.lock, flags); | |
5e928f77 RW |
1019 | |
1020 | return retval; | |
1021 | } | |
140a6c94 | 1022 | EXPORT_SYMBOL_GPL(__pm_runtime_suspend); |
5e928f77 RW |
1023 | |
1024 | /** | |
62052ab1 | 1025 | * __pm_runtime_resume - Entry point for runtime resume operations. |
140a6c94 | 1026 | * @dev: Device to resume. |
3f9af051 | 1027 | * @rpmflags: Flag bits. |
5e928f77 | 1028 | * |
140a6c94 AS |
1029 | * If the RPM_GET_PUT flag is set, increment the device's usage count. Then |
1030 | * carry out a resume, either synchronous or asynchronous. | |
1031 | * | |
311aab73 CC |
1032 | * This routine may be called in atomic context if the RPM_ASYNC flag is set, |
1033 | * or if pm_runtime_irq_safe() has been called. | |
5e928f77 | 1034 | */ |
140a6c94 | 1035 | int __pm_runtime_resume(struct device *dev, int rpmflags) |
5e928f77 | 1036 | { |
140a6c94 AS |
1037 | unsigned long flags; |
1038 | int retval; | |
5e928f77 | 1039 | |
a9306a63 RW |
1040 | might_sleep_if(!(rpmflags & RPM_ASYNC) && !dev->power.irq_safe && |
1041 | dev->power.runtime_status != RPM_ACTIVE); | |
311aab73 | 1042 | |
140a6c94 AS |
1043 | if (rpmflags & RPM_GET_PUT) |
1044 | atomic_inc(&dev->power.usage_count); | |
1045 | ||
1046 | spin_lock_irqsave(&dev->power.lock, flags); | |
1047 | retval = rpm_resume(dev, rpmflags); | |
1048 | spin_unlock_irqrestore(&dev->power.lock, flags); | |
5e928f77 RW |
1049 | |
1050 | return retval; | |
1051 | } | |
140a6c94 | 1052 | EXPORT_SYMBOL_GPL(__pm_runtime_resume); |
5e928f77 | 1053 | |
a436b6a1 RW |
1054 | /** |
1055 | * pm_runtime_get_if_in_use - Conditionally bump up the device's usage counter. | |
1056 | * @dev: Device to handle. | |
1057 | * | |
1058 | * Return -EINVAL if runtime PM is disabled for the device. | |
1059 | * | |
1060 | * If that's not the case and if the device's runtime PM status is RPM_ACTIVE | |
1061 | * and the runtime PM usage counter is nonzero, increment the counter and | |
1062 | * return 1. Otherwise return 0 without changing the counter. | |
1063 | */ | |
1064 | int pm_runtime_get_if_in_use(struct device *dev) | |
1065 | { | |
1066 | unsigned long flags; | |
1067 | int retval; | |
1068 | ||
1069 | spin_lock_irqsave(&dev->power.lock, flags); | |
1070 | retval = dev->power.disable_depth > 0 ? -EINVAL : | |
1071 | dev->power.runtime_status == RPM_ACTIVE | |
1072 | && atomic_inc_not_zero(&dev->power.usage_count); | |
1073 | spin_unlock_irqrestore(&dev->power.lock, flags); | |
1074 | return retval; | |
1075 | } | |
1076 | EXPORT_SYMBOL_GPL(pm_runtime_get_if_in_use); | |
1077 | ||
5e928f77 | 1078 | /** |
62052ab1 | 1079 | * __pm_runtime_set_status - Set runtime PM status of a device. |
5e928f77 | 1080 | * @dev: Device to handle. |
62052ab1 | 1081 | * @status: New runtime PM status of the device. |
5e928f77 | 1082 | * |
62052ab1 | 1083 | * If runtime PM of the device is disabled or its power.runtime_error field is |
5e928f77 RW |
1084 | * different from zero, the status may be changed either to RPM_ACTIVE, or to |
1085 | * RPM_SUSPENDED, as long as that reflects the actual state of the device. | |
1086 | * However, if the device has a parent and the parent is not active, and the | |
1087 | * parent's power.ignore_children flag is unset, the device's status cannot be | |
1088 | * set to RPM_ACTIVE, so -EBUSY is returned in that case. | |
1089 | * | |
1090 | * If successful, __pm_runtime_set_status() clears the power.runtime_error field | |
1091 | * and the device parent's counter of unsuspended children is modified to | |
1092 | * reflect the new status. If the new status is RPM_SUSPENDED, an idle | |
1093 | * notification request for the parent is submitted. | |
1094 | */ | |
1095 | int __pm_runtime_set_status(struct device *dev, unsigned int status) | |
1096 | { | |
1097 | struct device *parent = dev->parent; | |
1098 | unsigned long flags; | |
1099 | bool notify_parent = false; | |
1100 | int error = 0; | |
1101 | ||
1102 | if (status != RPM_ACTIVE && status != RPM_SUSPENDED) | |
1103 | return -EINVAL; | |
1104 | ||
1105 | spin_lock_irqsave(&dev->power.lock, flags); | |
1106 | ||
1107 | if (!dev->power.runtime_error && !dev->power.disable_depth) { | |
1108 | error = -EAGAIN; | |
1109 | goto out; | |
1110 | } | |
1111 | ||
f8817f61 | 1112 | if (dev->power.runtime_status == status || !parent) |
5e928f77 RW |
1113 | goto out_set; |
1114 | ||
1115 | if (status == RPM_SUSPENDED) { | |
f8817f61 RW |
1116 | atomic_add_unless(&parent->power.child_count, -1, 0); |
1117 | notify_parent = !parent->power.ignore_children; | |
1118 | } else { | |
bab636b9 | 1119 | spin_lock_nested(&parent->power.lock, SINGLE_DEPTH_NESTING); |
5e928f77 RW |
1120 | |
1121 | /* | |
1122 | * It is invalid to put an active child under a parent that is | |
62052ab1 | 1123 | * not active, has runtime PM enabled and the |
5e928f77 RW |
1124 | * 'power.ignore_children' flag unset. |
1125 | */ | |
1126 | if (!parent->power.disable_depth | |
1127 | && !parent->power.ignore_children | |
71723f95 LW |
1128 | && parent->power.runtime_status != RPM_ACTIVE) { |
1129 | dev_err(dev, "runtime PM trying to activate child device %s but parent (%s) is not active\n", | |
1130 | dev_name(dev), | |
1131 | dev_name(parent)); | |
5e928f77 | 1132 | error = -EBUSY; |
71723f95 | 1133 | } else if (dev->power.runtime_status == RPM_SUSPENDED) { |
965c4ac0 | 1134 | atomic_inc(&parent->power.child_count); |
71723f95 | 1135 | } |
5e928f77 | 1136 | |
862f89b3 | 1137 | spin_unlock(&parent->power.lock); |
5e928f77 RW |
1138 | |
1139 | if (error) | |
1140 | goto out; | |
1141 | } | |
1142 | ||
1143 | out_set: | |
8d4b9d1b | 1144 | __update_runtime_status(dev, status); |
5e928f77 RW |
1145 | dev->power.runtime_error = 0; |
1146 | out: | |
1147 | spin_unlock_irqrestore(&dev->power.lock, flags); | |
1148 | ||
1149 | if (notify_parent) | |
1150 | pm_request_idle(parent); | |
1151 | ||
1152 | return error; | |
1153 | } | |
1154 | EXPORT_SYMBOL_GPL(__pm_runtime_set_status); | |
1155 | ||
1156 | /** | |
1157 | * __pm_runtime_barrier - Cancel pending requests and wait for completions. | |
1158 | * @dev: Device to handle. | |
1159 | * | |
1160 | * Flush all pending requests for the device from pm_wq and wait for all | |
62052ab1 | 1161 | * runtime PM operations involving the device in progress to complete. |
5e928f77 RW |
1162 | * |
1163 | * Should be called under dev->power.lock with interrupts disabled. | |
1164 | */ | |
1165 | static void __pm_runtime_barrier(struct device *dev) | |
1166 | { | |
1167 | pm_runtime_deactivate_timer(dev); | |
1168 | ||
1169 | if (dev->power.request_pending) { | |
1170 | dev->power.request = RPM_REQ_NONE; | |
1171 | spin_unlock_irq(&dev->power.lock); | |
1172 | ||
1173 | cancel_work_sync(&dev->power.work); | |
1174 | ||
1175 | spin_lock_irq(&dev->power.lock); | |
1176 | dev->power.request_pending = false; | |
1177 | } | |
1178 | ||
1179 | if (dev->power.runtime_status == RPM_SUSPENDING | |
1180 | || dev->power.runtime_status == RPM_RESUMING | |
1181 | || dev->power.idle_notification) { | |
1182 | DEFINE_WAIT(wait); | |
1183 | ||
1184 | /* Suspend, wake-up or idle notification in progress. */ | |
1185 | for (;;) { | |
1186 | prepare_to_wait(&dev->power.wait_queue, &wait, | |
1187 | TASK_UNINTERRUPTIBLE); | |
1188 | if (dev->power.runtime_status != RPM_SUSPENDING | |
1189 | && dev->power.runtime_status != RPM_RESUMING | |
1190 | && !dev->power.idle_notification) | |
1191 | break; | |
1192 | spin_unlock_irq(&dev->power.lock); | |
1193 | ||
1194 | schedule(); | |
1195 | ||
1196 | spin_lock_irq(&dev->power.lock); | |
1197 | } | |
1198 | finish_wait(&dev->power.wait_queue, &wait); | |
1199 | } | |
1200 | } | |
1201 | ||
1202 | /** | |
1203 | * pm_runtime_barrier - Flush pending requests and wait for completions. | |
1204 | * @dev: Device to handle. | |
1205 | * | |
1206 | * Prevent the device from being suspended by incrementing its usage counter and | |
1207 | * if there's a pending resume request for the device, wake the device up. | |
1208 | * Next, make sure that all pending requests for the device have been flushed | |
62052ab1 | 1209 | * from pm_wq and wait for all runtime PM operations involving the device in |
5e928f77 RW |
1210 | * progress to complete. |
1211 | * | |
1212 | * Return value: | |
1213 | * 1, if there was a resume request pending and the device had to be woken up, | |
1214 | * 0, otherwise | |
1215 | */ | |
1216 | int pm_runtime_barrier(struct device *dev) | |
1217 | { | |
1218 | int retval = 0; | |
1219 | ||
1220 | pm_runtime_get_noresume(dev); | |
1221 | spin_lock_irq(&dev->power.lock); | |
1222 | ||
1223 | if (dev->power.request_pending | |
1224 | && dev->power.request == RPM_REQ_RESUME) { | |
140a6c94 | 1225 | rpm_resume(dev, 0); |
5e928f77 RW |
1226 | retval = 1; |
1227 | } | |
1228 | ||
1229 | __pm_runtime_barrier(dev); | |
1230 | ||
1231 | spin_unlock_irq(&dev->power.lock); | |
1232 | pm_runtime_put_noidle(dev); | |
1233 | ||
1234 | return retval; | |
1235 | } | |
1236 | EXPORT_SYMBOL_GPL(pm_runtime_barrier); | |
1237 | ||
1238 | /** | |
62052ab1 | 1239 | * __pm_runtime_disable - Disable runtime PM of a device. |
5e928f77 RW |
1240 | * @dev: Device to handle. |
1241 | * @check_resume: If set, check if there's a resume request for the device. | |
1242 | * | |
7b60894f | 1243 | * Increment power.disable_depth for the device and if it was zero previously, |
62052ab1 | 1244 | * cancel all pending runtime PM requests for the device and wait for all |
5e928f77 | 1245 | * operations in progress to complete. The device can be either active or |
62052ab1 | 1246 | * suspended after its runtime PM has been disabled. |
5e928f77 RW |
1247 | * |
1248 | * If @check_resume is set and there's a resume request pending when | |
1249 | * __pm_runtime_disable() is called and power.disable_depth is zero, the | |
62052ab1 | 1250 | * function will wake up the device before disabling its runtime PM. |
5e928f77 RW |
1251 | */ |
1252 | void __pm_runtime_disable(struct device *dev, bool check_resume) | |
1253 | { | |
1254 | spin_lock_irq(&dev->power.lock); | |
1255 | ||
1256 | if (dev->power.disable_depth > 0) { | |
1257 | dev->power.disable_depth++; | |
1258 | goto out; | |
1259 | } | |
1260 | ||
1261 | /* | |
1262 | * Wake up the device if there's a resume request pending, because that | |
62052ab1 | 1263 | * means there probably is some I/O to process and disabling runtime PM |
5e928f77 RW |
1264 | * shouldn't prevent the device from processing the I/O. |
1265 | */ | |
1266 | if (check_resume && dev->power.request_pending | |
1267 | && dev->power.request == RPM_REQ_RESUME) { | |
1268 | /* | |
1269 | * Prevent suspends and idle notifications from being carried | |
1270 | * out after we have woken up the device. | |
1271 | */ | |
1272 | pm_runtime_get_noresume(dev); | |
1273 | ||
140a6c94 | 1274 | rpm_resume(dev, 0); |
5e928f77 RW |
1275 | |
1276 | pm_runtime_put_noidle(dev); | |
1277 | } | |
1278 | ||
1279 | if (!dev->power.disable_depth++) | |
1280 | __pm_runtime_barrier(dev); | |
1281 | ||
1282 | out: | |
1283 | spin_unlock_irq(&dev->power.lock); | |
1284 | } | |
1285 | EXPORT_SYMBOL_GPL(__pm_runtime_disable); | |
1286 | ||
1287 | /** | |
62052ab1 | 1288 | * pm_runtime_enable - Enable runtime PM of a device. |
5e928f77 RW |
1289 | * @dev: Device to handle. |
1290 | */ | |
1291 | void pm_runtime_enable(struct device *dev) | |
1292 | { | |
1293 | unsigned long flags; | |
1294 | ||
1295 | spin_lock_irqsave(&dev->power.lock, flags); | |
1296 | ||
1297 | if (dev->power.disable_depth > 0) | |
1298 | dev->power.disable_depth--; | |
1299 | else | |
1300 | dev_warn(dev, "Unbalanced %s!\n", __func__); | |
1301 | ||
f8817f61 RW |
1302 | WARN(!dev->power.disable_depth && |
1303 | dev->power.runtime_status == RPM_SUSPENDED && | |
1304 | !dev->power.ignore_children && | |
1305 | atomic_read(&dev->power.child_count) > 0, | |
1306 | "Enabling runtime PM for inactive device (%s) with active children\n", | |
1307 | dev_name(dev)); | |
1308 | ||
5e928f77 RW |
1309 | spin_unlock_irqrestore(&dev->power.lock, flags); |
1310 | } | |
1311 | EXPORT_SYMBOL_GPL(pm_runtime_enable); | |
1312 | ||
53823639 | 1313 | /** |
62052ab1 | 1314 | * pm_runtime_forbid - Block runtime PM of a device. |
53823639 RW |
1315 | * @dev: Device to handle. |
1316 | * | |
1317 | * Increase the device's usage count and clear its power.runtime_auto flag, | |
1318 | * so that it cannot be suspended at run time until pm_runtime_allow() is called | |
1319 | * for it. | |
1320 | */ | |
1321 | void pm_runtime_forbid(struct device *dev) | |
1322 | { | |
1323 | spin_lock_irq(&dev->power.lock); | |
1324 | if (!dev->power.runtime_auto) | |
1325 | goto out; | |
1326 | ||
1327 | dev->power.runtime_auto = false; | |
1328 | atomic_inc(&dev->power.usage_count); | |
140a6c94 | 1329 | rpm_resume(dev, 0); |
53823639 RW |
1330 | |
1331 | out: | |
1332 | spin_unlock_irq(&dev->power.lock); | |
1333 | } | |
1334 | EXPORT_SYMBOL_GPL(pm_runtime_forbid); | |
1335 | ||
1336 | /** | |
62052ab1 | 1337 | * pm_runtime_allow - Unblock runtime PM of a device. |
53823639 RW |
1338 | * @dev: Device to handle. |
1339 | * | |
1340 | * Decrease the device's usage count and set its power.runtime_auto flag. | |
1341 | */ | |
1342 | void pm_runtime_allow(struct device *dev) | |
1343 | { | |
1344 | spin_lock_irq(&dev->power.lock); | |
1345 | if (dev->power.runtime_auto) | |
1346 | goto out; | |
1347 | ||
1348 | dev->power.runtime_auto = true; | |
1349 | if (atomic_dec_and_test(&dev->power.usage_count)) | |
fe7450b0 | 1350 | rpm_idle(dev, RPM_AUTO | RPM_ASYNC); |
53823639 RW |
1351 | |
1352 | out: | |
1353 | spin_unlock_irq(&dev->power.lock); | |
1354 | } | |
1355 | EXPORT_SYMBOL_GPL(pm_runtime_allow); | |
1356 | ||
7490e442 | 1357 | /** |
62052ab1 | 1358 | * pm_runtime_no_callbacks - Ignore runtime PM callbacks for a device. |
7490e442 AS |
1359 | * @dev: Device to handle. |
1360 | * | |
1361 | * Set the power.no_callbacks flag, which tells the PM core that this | |
62052ab1 RW |
1362 | * device is power-managed through its parent and has no runtime PM |
1363 | * callbacks of its own. The runtime sysfs attributes will be removed. | |
7490e442 AS |
1364 | */ |
1365 | void pm_runtime_no_callbacks(struct device *dev) | |
1366 | { | |
1367 | spin_lock_irq(&dev->power.lock); | |
1368 | dev->power.no_callbacks = 1; | |
1369 | spin_unlock_irq(&dev->power.lock); | |
1370 | if (device_is_registered(dev)) | |
1371 | rpm_sysfs_remove(dev); | |
1372 | } | |
1373 | EXPORT_SYMBOL_GPL(pm_runtime_no_callbacks); | |
1374 | ||
c7b61de5 AS |
1375 | /** |
1376 | * pm_runtime_irq_safe - Leave interrupts disabled during callbacks. | |
1377 | * @dev: Device to handle | |
1378 | * | |
1379 | * Set the power.irq_safe flag, which tells the PM core that the | |
1380 | * ->runtime_suspend() and ->runtime_resume() callbacks for this device should | |
1381 | * always be invoked with the spinlock held and interrupts disabled. It also | |
1382 | * causes the parent's usage counter to be permanently incremented, preventing | |
1383 | * the parent from runtime suspending -- otherwise an irq-safe child might have | |
1384 | * to wait for a non-irq-safe parent. | |
1385 | */ | |
1386 | void pm_runtime_irq_safe(struct device *dev) | |
1387 | { | |
1388 | if (dev->parent) | |
1389 | pm_runtime_get_sync(dev->parent); | |
1390 | spin_lock_irq(&dev->power.lock); | |
1391 | dev->power.irq_safe = 1; | |
1392 | spin_unlock_irq(&dev->power.lock); | |
1393 | } | |
1394 | EXPORT_SYMBOL_GPL(pm_runtime_irq_safe); | |
1395 | ||
15bcb91d AS |
1396 | /** |
1397 | * update_autosuspend - Handle a change to a device's autosuspend settings. | |
1398 | * @dev: Device to handle. | |
1399 | * @old_delay: The former autosuspend_delay value. | |
1400 | * @old_use: The former use_autosuspend value. | |
1401 | * | |
1402 | * Prevent runtime suspend if the new delay is negative and use_autosuspend is | |
1403 | * set; otherwise allow it. Send an idle notification if suspends are allowed. | |
1404 | * | |
1405 | * This function must be called under dev->power.lock with interrupts disabled. | |
1406 | */ | |
1407 | static void update_autosuspend(struct device *dev, int old_delay, int old_use) | |
1408 | { | |
1409 | int delay = dev->power.autosuspend_delay; | |
1410 | ||
1411 | /* Should runtime suspend be prevented now? */ | |
1412 | if (dev->power.use_autosuspend && delay < 0) { | |
1413 | ||
1414 | /* If it used to be allowed then prevent it. */ | |
1415 | if (!old_use || old_delay >= 0) { | |
1416 | atomic_inc(&dev->power.usage_count); | |
1417 | rpm_resume(dev, 0); | |
1418 | } | |
1419 | } | |
1420 | ||
1421 | /* Runtime suspend should be allowed now. */ | |
1422 | else { | |
1423 | ||
1424 | /* If it used to be prevented then allow it. */ | |
1425 | if (old_use && old_delay < 0) | |
1426 | atomic_dec(&dev->power.usage_count); | |
1427 | ||
1428 | /* Maybe we can autosuspend now. */ | |
1429 | rpm_idle(dev, RPM_AUTO); | |
1430 | } | |
1431 | } | |
1432 | ||
1433 | /** | |
1434 | * pm_runtime_set_autosuspend_delay - Set a device's autosuspend_delay value. | |
1435 | * @dev: Device to handle. | |
1436 | * @delay: Value of the new delay in milliseconds. | |
1437 | * | |
1438 | * Set the device's power.autosuspend_delay value. If it changes to negative | |
62052ab1 RW |
1439 | * and the power.use_autosuspend flag is set, prevent runtime suspends. If it |
1440 | * changes the other way, allow runtime suspends. | |
15bcb91d AS |
1441 | */ |
1442 | void pm_runtime_set_autosuspend_delay(struct device *dev, int delay) | |
1443 | { | |
1444 | int old_delay, old_use; | |
1445 | ||
1446 | spin_lock_irq(&dev->power.lock); | |
1447 | old_delay = dev->power.autosuspend_delay; | |
1448 | old_use = dev->power.use_autosuspend; | |
1449 | dev->power.autosuspend_delay = delay; | |
1450 | update_autosuspend(dev, old_delay, old_use); | |
1451 | spin_unlock_irq(&dev->power.lock); | |
1452 | } | |
1453 | EXPORT_SYMBOL_GPL(pm_runtime_set_autosuspend_delay); | |
1454 | ||
1455 | /** | |
1456 | * __pm_runtime_use_autosuspend - Set a device's use_autosuspend flag. | |
1457 | * @dev: Device to handle. | |
1458 | * @use: New value for use_autosuspend. | |
1459 | * | |
62052ab1 | 1460 | * Set the device's power.use_autosuspend flag, and allow or prevent runtime |
15bcb91d AS |
1461 | * suspends as needed. |
1462 | */ | |
1463 | void __pm_runtime_use_autosuspend(struct device *dev, bool use) | |
1464 | { | |
1465 | int old_delay, old_use; | |
1466 | ||
1467 | spin_lock_irq(&dev->power.lock); | |
1468 | old_delay = dev->power.autosuspend_delay; | |
1469 | old_use = dev->power.use_autosuspend; | |
1470 | dev->power.use_autosuspend = use; | |
1471 | update_autosuspend(dev, old_delay, old_use); | |
1472 | spin_unlock_irq(&dev->power.lock); | |
1473 | } | |
1474 | EXPORT_SYMBOL_GPL(__pm_runtime_use_autosuspend); | |
1475 | ||
5e928f77 | 1476 | /** |
62052ab1 | 1477 | * pm_runtime_init - Initialize runtime PM fields in given device object. |
5e928f77 RW |
1478 | * @dev: Device object to initialize. |
1479 | */ | |
1480 | void pm_runtime_init(struct device *dev) | |
1481 | { | |
5e928f77 RW |
1482 | dev->power.runtime_status = RPM_SUSPENDED; |
1483 | dev->power.idle_notification = false; | |
1484 | ||
1485 | dev->power.disable_depth = 1; | |
1486 | atomic_set(&dev->power.usage_count, 0); | |
1487 | ||
1488 | dev->power.runtime_error = 0; | |
1489 | ||
1490 | atomic_set(&dev->power.child_count, 0); | |
1491 | pm_suspend_ignore_children(dev, false); | |
53823639 | 1492 | dev->power.runtime_auto = true; |
5e928f77 RW |
1493 | |
1494 | dev->power.request_pending = false; | |
1495 | dev->power.request = RPM_REQ_NONE; | |
1496 | dev->power.deferred_resume = false; | |
8d4b9d1b | 1497 | dev->power.accounting_timestamp = jiffies; |
5e928f77 RW |
1498 | INIT_WORK(&dev->power.work, pm_runtime_work); |
1499 | ||
1500 | dev->power.timer_expires = 0; | |
8234f673 VG |
1501 | hrtimer_init(&dev->power.suspend_timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS); |
1502 | dev->power.suspend_timer.function = pm_suspend_timer_fn; | |
5e928f77 RW |
1503 | |
1504 | init_waitqueue_head(&dev->power.wait_queue); | |
1505 | } | |
1506 | ||
5de85b9d UH |
1507 | /** |
1508 | * pm_runtime_reinit - Re-initialize runtime PM fields in given device object. | |
1509 | * @dev: Device object to re-initialize. | |
1510 | */ | |
1511 | void pm_runtime_reinit(struct device *dev) | |
1512 | { | |
1513 | if (!pm_runtime_enabled(dev)) { | |
1514 | if (dev->power.runtime_status == RPM_ACTIVE) | |
1515 | pm_runtime_set_suspended(dev); | |
1516 | if (dev->power.irq_safe) { | |
1517 | spin_lock_irq(&dev->power.lock); | |
1518 | dev->power.irq_safe = 0; | |
1519 | spin_unlock_irq(&dev->power.lock); | |
1520 | if (dev->parent) | |
1521 | pm_runtime_put(dev->parent); | |
1522 | } | |
1523 | } | |
1524 | } | |
1525 | ||
5e928f77 RW |
1526 | /** |
1527 | * pm_runtime_remove - Prepare for removing a device from device hierarchy. | |
1528 | * @dev: Device object being removed from device hierarchy. | |
1529 | */ | |
1530 | void pm_runtime_remove(struct device *dev) | |
1531 | { | |
1532 | __pm_runtime_disable(dev, false); | |
5de85b9d | 1533 | pm_runtime_reinit(dev); |
5e928f77 | 1534 | } |
37f20416 | 1535 | |
21d5c57b RW |
1536 | /** |
1537 | * pm_runtime_clean_up_links - Prepare links to consumers for driver removal. | |
1538 | * @dev: Device whose driver is going to be removed. | |
1539 | * | |
1540 | * Check links from this device to any consumers and if any of them have active | |
1541 | * runtime PM references to the device, drop the usage counter of the device | |
1542 | * (once per link). | |
1543 | * | |
1544 | * Links with the DL_FLAG_STATELESS flag set are ignored. | |
1545 | * | |
1546 | * Since the device is guaranteed to be runtime-active at the point this is | |
1547 | * called, nothing else needs to be done here. | |
1548 | * | |
1549 | * Moreover, this is called after device_links_busy() has returned 'false', so | |
1550 | * the status of each link is guaranteed to be DL_STATE_SUPPLIER_UNBIND and | |
1551 | * therefore rpm_active can't be manipulated concurrently. | |
1552 | */ | |
1553 | void pm_runtime_clean_up_links(struct device *dev) | |
1554 | { | |
1555 | struct device_link *link; | |
1556 | int idx; | |
1557 | ||
1558 | idx = device_links_read_lock(); | |
1559 | ||
1560 | list_for_each_entry_rcu(link, &dev->links.consumers, s_node) { | |
1561 | if (link->flags & DL_FLAG_STATELESS) | |
1562 | continue; | |
1563 | ||
1564 | if (link->rpm_active) { | |
1565 | pm_runtime_put_noidle(dev); | |
1566 | link->rpm_active = false; | |
1567 | } | |
1568 | } | |
1569 | ||
1570 | device_links_read_unlock(idx); | |
1571 | } | |
1572 | ||
1573 | /** | |
b06c0b2f | 1574 | * pm_runtime_get_suppliers - Resume and reference-count supplier devices. |
21d5c57b RW |
1575 | * @dev: Consumer device. |
1576 | */ | |
b06c0b2f | 1577 | void pm_runtime_get_suppliers(struct device *dev) |
21d5c57b | 1578 | { |
b06c0b2f | 1579 | struct device_link *link; |
21d5c57b RW |
1580 | int idx; |
1581 | ||
1582 | idx = device_links_read_lock(); | |
1583 | ||
b06c0b2f RW |
1584 | list_for_each_entry_rcu(link, &dev->links.suppliers, c_node) |
1585 | if (link->flags & DL_FLAG_PM_RUNTIME) | |
1586 | pm_runtime_get_sync(link->supplier); | |
1587 | ||
1588 | device_links_read_unlock(idx); | |
1589 | } | |
1590 | ||
1591 | /** | |
1592 | * pm_runtime_put_suppliers - Drop references to supplier devices. | |
1593 | * @dev: Consumer device. | |
1594 | */ | |
1595 | void pm_runtime_put_suppliers(struct device *dev) | |
1596 | { | |
1597 | struct device_link *link; | |
1598 | int idx; | |
1599 | ||
1600 | idx = device_links_read_lock(); | |
1601 | ||
1602 | list_for_each_entry_rcu(link, &dev->links.suppliers, c_node) | |
1603 | if (link->flags & DL_FLAG_PM_RUNTIME) | |
1604 | pm_runtime_put(link->supplier); | |
21d5c57b RW |
1605 | |
1606 | device_links_read_unlock(idx); | |
1607 | } | |
1608 | ||
baa8809f RW |
1609 | void pm_runtime_new_link(struct device *dev) |
1610 | { | |
1611 | spin_lock_irq(&dev->power.lock); | |
1612 | dev->power.links_count++; | |
1613 | spin_unlock_irq(&dev->power.lock); | |
1614 | } | |
1615 | ||
1616 | void pm_runtime_drop_link(struct device *dev) | |
1617 | { | |
a0504aec UH |
1618 | rpm_put_suppliers(dev); |
1619 | ||
baa8809f RW |
1620 | spin_lock_irq(&dev->power.lock); |
1621 | WARN_ON(dev->power.links_count == 0); | |
1622 | dev->power.links_count--; | |
1623 | spin_unlock_irq(&dev->power.lock); | |
1624 | } | |
1625 | ||
4918e1f8 RW |
1626 | static bool pm_runtime_need_not_resume(struct device *dev) |
1627 | { | |
1628 | return atomic_read(&dev->power.usage_count) <= 1 && | |
1f5c6855 RW |
1629 | (atomic_read(&dev->power.child_count) == 0 || |
1630 | dev->power.ignore_children); | |
4918e1f8 RW |
1631 | } |
1632 | ||
37f20416 UH |
1633 | /** |
1634 | * pm_runtime_force_suspend - Force a device into suspend state if needed. | |
1635 | * @dev: Device to suspend. | |
1636 | * | |
1637 | * Disable runtime PM so we safely can check the device's runtime PM status and | |
4918e1f8 RW |
1638 | * if it is active, invoke its ->runtime_suspend callback to suspend it and |
1639 | * change its runtime PM status field to RPM_SUSPENDED. Also, if the device's | |
1640 | * usage and children counters don't indicate that the device was in use before | |
1641 | * the system-wide transition under way, decrement its parent's children counter | |
1642 | * (if there is a parent). Keep runtime PM disabled to preserve the state | |
1643 | * unless we encounter errors. | |
37f20416 UH |
1644 | * |
1645 | * Typically this function may be invoked from a system suspend callback to make | |
4918e1f8 RW |
1646 | * sure the device is put into low power state and it should only be used during |
1647 | * system-wide PM transitions to sleep states. It assumes that the analogous | |
1648 | * pm_runtime_force_resume() will be used to resume the device. | |
37f20416 UH |
1649 | */ |
1650 | int pm_runtime_force_suspend(struct device *dev) | |
1651 | { | |
1652 | int (*callback)(struct device *); | |
617fcb67 | 1653 | int ret; |
37f20416 UH |
1654 | |
1655 | pm_runtime_disable(dev); | |
37f20416 UH |
1656 | if (pm_runtime_status_suspended(dev)) |
1657 | return 0; | |
1658 | ||
dbcd2d72 | 1659 | callback = RPM_GET_CALLBACK(dev, runtime_suspend); |
37f20416 | 1660 | |
617fcb67 | 1661 | ret = callback ? callback(dev) : 0; |
37f20416 UH |
1662 | if (ret) |
1663 | goto err; | |
1664 | ||
1d9174fb | 1665 | /* |
4918e1f8 RW |
1666 | * If the device can stay in suspend after the system-wide transition |
1667 | * to the working state that will follow, drop the children counter of | |
1668 | * its parent, but set its status to RPM_SUSPENDED anyway in case this | |
1669 | * function will be called again for it in the meantime. | |
1d9174fb | 1670 | */ |
4918e1f8 RW |
1671 | if (pm_runtime_need_not_resume(dev)) |
1672 | pm_runtime_set_suspended(dev); | |
1673 | else | |
1674 | __update_runtime_status(dev, RPM_SUSPENDED); | |
1d9174fb | 1675 | |
37f20416 | 1676 | return 0; |
4918e1f8 | 1677 | |
37f20416 UH |
1678 | err: |
1679 | pm_runtime_enable(dev); | |
1680 | return ret; | |
1681 | } | |
1682 | EXPORT_SYMBOL_GPL(pm_runtime_force_suspend); | |
1683 | ||
1684 | /** | |
1d9174fb | 1685 | * pm_runtime_force_resume - Force a device into resume state if needed. |
37f20416 UH |
1686 | * @dev: Device to resume. |
1687 | * | |
1688 | * Prior invoking this function we expect the user to have brought the device | |
1689 | * into low power state by a call to pm_runtime_force_suspend(). Here we reverse | |
4918e1f8 RW |
1690 | * those actions and bring the device into full power, if it is expected to be |
1691 | * used on system resume. In the other case, we defer the resume to be managed | |
1692 | * via runtime PM. | |
37f20416 | 1693 | * |
1d9174fb | 1694 | * Typically this function may be invoked from a system resume callback. |
37f20416 UH |
1695 | */ |
1696 | int pm_runtime_force_resume(struct device *dev) | |
1697 | { | |
1698 | int (*callback)(struct device *); | |
1699 | int ret = 0; | |
1700 | ||
4918e1f8 | 1701 | if (!pm_runtime_status_suspended(dev) || pm_runtime_need_not_resume(dev)) |
9f5b5274 UH |
1702 | goto out; |
1703 | ||
1d9174fb | 1704 | /* |
4918e1f8 RW |
1705 | * The value of the parent's children counter is correct already, so |
1706 | * just update the status of the device. | |
1707 | */ | |
1708 | __update_runtime_status(dev, RPM_ACTIVE); | |
1d9174fb | 1709 | |
4918e1f8 | 1710 | callback = RPM_GET_CALLBACK(dev, runtime_resume); |
37f20416 | 1711 | |
617fcb67 | 1712 | ret = callback ? callback(dev) : 0; |
0ae3aeef UH |
1713 | if (ret) { |
1714 | pm_runtime_set_suspended(dev); | |
1715 | goto out; | |
1716 | } | |
1717 | ||
37f20416 UH |
1718 | pm_runtime_mark_last_busy(dev); |
1719 | out: | |
1720 | pm_runtime_enable(dev); | |
1721 | return ret; | |
1722 | } | |
1723 | EXPORT_SYMBOL_GPL(pm_runtime_force_resume); |