Commit | Line | Data |
---|---|---|
5e928f77 | 1 | /* |
62052ab1 | 2 | * drivers/base/power/runtime.c - Helper functions for device runtime PM |
5e928f77 RW |
3 | * |
4 | * Copyright (c) 2009 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc. | |
1bfee5bc | 5 | * Copyright (C) 2010 Alan Stern <stern@rowland.harvard.edu> |
5e928f77 RW |
6 | * |
7 | * This file is released under the GPLv2. | |
8 | */ | |
9 | ||
10 | #include <linux/sched.h> | |
11 | #include <linux/pm_runtime.h> | |
c3dc2f14 | 12 | #include <trace/events/rpm.h> |
7490e442 | 13 | #include "power.h" |
5e928f77 | 14 | |
140a6c94 | 15 | static int rpm_resume(struct device *dev, int rpmflags); |
7490e442 | 16 | static int rpm_suspend(struct device *dev, int rpmflags); |
5e928f77 | 17 | |
4769373c AS |
18 | /** |
19 | * update_pm_runtime_accounting - Update the time accounting of power states | |
20 | * @dev: Device to update the accounting for | |
21 | * | |
22 | * In order to be able to have time accounting of the various power states | |
23 | * (as used by programs such as PowerTOP to show the effectiveness of runtime | |
24 | * PM), we need to track the time spent in each state. | |
25 | * update_pm_runtime_accounting must be called each time before the | |
26 | * runtime_status field is updated, to account the time in the old state | |
27 | * correctly. | |
28 | */ | |
29 | void update_pm_runtime_accounting(struct device *dev) | |
30 | { | |
31 | unsigned long now = jiffies; | |
32 | int delta; | |
33 | ||
34 | delta = now - dev->power.accounting_timestamp; | |
35 | ||
36 | if (delta < 0) | |
37 | delta = 0; | |
38 | ||
39 | dev->power.accounting_timestamp = now; | |
40 | ||
41 | if (dev->power.disable_depth > 0) | |
42 | return; | |
43 | ||
44 | if (dev->power.runtime_status == RPM_SUSPENDED) | |
45 | dev->power.suspended_jiffies += delta; | |
46 | else | |
47 | dev->power.active_jiffies += delta; | |
48 | } | |
49 | ||
50 | static void __update_runtime_status(struct device *dev, enum rpm_status status) | |
51 | { | |
52 | update_pm_runtime_accounting(dev); | |
53 | dev->power.runtime_status = status; | |
54 | } | |
55 | ||
5e928f77 RW |
56 | /** |
57 | * pm_runtime_deactivate_timer - Deactivate given device's suspend timer. | |
58 | * @dev: Device to handle. | |
59 | */ | |
60 | static void pm_runtime_deactivate_timer(struct device *dev) | |
61 | { | |
62 | if (dev->power.timer_expires > 0) { | |
63 | del_timer(&dev->power.suspend_timer); | |
64 | dev->power.timer_expires = 0; | |
65 | } | |
66 | } | |
67 | ||
68 | /** | |
69 | * pm_runtime_cancel_pending - Deactivate suspend timer and cancel requests. | |
70 | * @dev: Device to handle. | |
71 | */ | |
72 | static void pm_runtime_cancel_pending(struct device *dev) | |
73 | { | |
74 | pm_runtime_deactivate_timer(dev); | |
75 | /* | |
76 | * In case there's a request pending, make sure its work function will | |
77 | * return without doing anything. | |
78 | */ | |
79 | dev->power.request = RPM_REQ_NONE; | |
80 | } | |
81 | ||
15bcb91d AS |
82 | /* |
83 | * pm_runtime_autosuspend_expiration - Get a device's autosuspend-delay expiration time. | |
84 | * @dev: Device to handle. | |
85 | * | |
86 | * Compute the autosuspend-delay expiration time based on the device's | |
87 | * power.last_busy time. If the delay has already expired or is disabled | |
88 | * (negative) or the power.use_autosuspend flag isn't set, return 0. | |
89 | * Otherwise return the expiration time in jiffies (adjusted to be nonzero). | |
90 | * | |
91 | * This function may be called either with or without dev->power.lock held. | |
92 | * Either way it can be racy, since power.last_busy may be updated at any time. | |
93 | */ | |
94 | unsigned long pm_runtime_autosuspend_expiration(struct device *dev) | |
95 | { | |
96 | int autosuspend_delay; | |
97 | long elapsed; | |
98 | unsigned long last_busy; | |
99 | unsigned long expires = 0; | |
100 | ||
101 | if (!dev->power.use_autosuspend) | |
102 | goto out; | |
103 | ||
104 | autosuspend_delay = ACCESS_ONCE(dev->power.autosuspend_delay); | |
105 | if (autosuspend_delay < 0) | |
106 | goto out; | |
107 | ||
108 | last_busy = ACCESS_ONCE(dev->power.last_busy); | |
109 | elapsed = jiffies - last_busy; | |
110 | if (elapsed < 0) | |
111 | goto out; /* jiffies has wrapped around. */ | |
112 | ||
113 | /* | |
114 | * If the autosuspend_delay is >= 1 second, align the timer by rounding | |
115 | * up to the nearest second. | |
116 | */ | |
117 | expires = last_busy + msecs_to_jiffies(autosuspend_delay); | |
118 | if (autosuspend_delay >= 1000) | |
119 | expires = round_jiffies(expires); | |
120 | expires += !expires; | |
121 | if (elapsed >= expires - last_busy) | |
122 | expires = 0; /* Already expired. */ | |
123 | ||
124 | out: | |
125 | return expires; | |
126 | } | |
127 | EXPORT_SYMBOL_GPL(pm_runtime_autosuspend_expiration); | |
128 | ||
5e928f77 | 129 | /** |
1bfee5bc AS |
130 | * rpm_check_suspend_allowed - Test whether a device may be suspended. |
131 | * @dev: Device to test. | |
5e928f77 | 132 | */ |
1bfee5bc | 133 | static int rpm_check_suspend_allowed(struct device *dev) |
5e928f77 RW |
134 | { |
135 | int retval = 0; | |
136 | ||
5e928f77 RW |
137 | if (dev->power.runtime_error) |
138 | retval = -EINVAL; | |
632e270e RW |
139 | else if (dev->power.disable_depth > 0) |
140 | retval = -EACCES; | |
141 | else if (atomic_read(&dev->power.usage_count) > 0) | |
5e928f77 RW |
142 | retval = -EAGAIN; |
143 | else if (!pm_children_suspended(dev)) | |
144 | retval = -EBUSY; | |
1bfee5bc AS |
145 | |
146 | /* Pending resume requests take precedence over suspends. */ | |
147 | else if ((dev->power.deferred_resume | |
78ca7c37 | 148 | && dev->power.runtime_status == RPM_SUSPENDING) |
1bfee5bc AS |
149 | || (dev->power.request_pending |
150 | && dev->power.request == RPM_REQ_RESUME)) | |
151 | retval = -EAGAIN; | |
152 | else if (dev->power.runtime_status == RPM_SUSPENDED) | |
153 | retval = 1; | |
154 | ||
155 | return retval; | |
156 | } | |
157 | ||
ad3c36a5 RW |
158 | /** |
159 | * __rpm_callback - Run a given runtime PM callback for a given device. | |
160 | * @cb: Runtime PM callback to run. | |
161 | * @dev: Device to run the callback for. | |
162 | */ | |
163 | static int __rpm_callback(int (*cb)(struct device *), struct device *dev) | |
164 | __releases(&dev->power.lock) __acquires(&dev->power.lock) | |
165 | { | |
166 | int retval; | |
167 | ||
168 | if (dev->power.irq_safe) | |
169 | spin_unlock(&dev->power.lock); | |
170 | else | |
171 | spin_unlock_irq(&dev->power.lock); | |
172 | ||
173 | retval = cb(dev); | |
174 | ||
175 | if (dev->power.irq_safe) | |
176 | spin_lock(&dev->power.lock); | |
177 | else | |
178 | spin_lock_irq(&dev->power.lock); | |
179 | ||
180 | return retval; | |
181 | } | |
182 | ||
1bfee5bc | 183 | /** |
140a6c94 | 184 | * rpm_idle - Notify device bus type if the device can be suspended. |
1bfee5bc AS |
185 | * @dev: Device to notify the bus type about. |
186 | * @rpmflags: Flag bits. | |
187 | * | |
62052ab1 | 188 | * Check if the device's runtime PM status allows it to be suspended. If |
1bfee5bc AS |
189 | * another idle notification has been started earlier, return immediately. If |
190 | * the RPM_ASYNC flag is set then queue an idle-notification request; otherwise | |
191 | * run the ->runtime_idle() callback directly. | |
192 | * | |
193 | * This function must be called under dev->power.lock with interrupts disabled. | |
194 | */ | |
140a6c94 | 195 | static int rpm_idle(struct device *dev, int rpmflags) |
1bfee5bc | 196 | { |
71c63122 | 197 | int (*callback)(struct device *); |
1bfee5bc AS |
198 | int retval; |
199 | ||
c3dc2f14 | 200 | trace_rpm_idle(dev, rpmflags); |
1bfee5bc AS |
201 | retval = rpm_check_suspend_allowed(dev); |
202 | if (retval < 0) | |
203 | ; /* Conditions are wrong. */ | |
204 | ||
205 | /* Idle notifications are allowed only in the RPM_ACTIVE state. */ | |
206 | else if (dev->power.runtime_status != RPM_ACTIVE) | |
207 | retval = -EAGAIN; | |
208 | ||
209 | /* | |
210 | * Any pending request other than an idle notification takes | |
211 | * precedence over us, except that the timer may be running. | |
212 | */ | |
213 | else if (dev->power.request_pending && | |
214 | dev->power.request > RPM_REQ_IDLE) | |
215 | retval = -EAGAIN; | |
216 | ||
217 | /* Act as though RPM_NOWAIT is always set. */ | |
218 | else if (dev->power.idle_notification) | |
219 | retval = -EINPROGRESS; | |
5e928f77 RW |
220 | if (retval) |
221 | goto out; | |
222 | ||
1bfee5bc AS |
223 | /* Pending requests need to be canceled. */ |
224 | dev->power.request = RPM_REQ_NONE; | |
225 | ||
7490e442 AS |
226 | if (dev->power.no_callbacks) { |
227 | /* Assume ->runtime_idle() callback would have suspended. */ | |
228 | retval = rpm_suspend(dev, rpmflags); | |
229 | goto out; | |
230 | } | |
231 | ||
1bfee5bc AS |
232 | /* Carry out an asynchronous or a synchronous idle notification. */ |
233 | if (rpmflags & RPM_ASYNC) { | |
234 | dev->power.request = RPM_REQ_IDLE; | |
235 | if (!dev->power.request_pending) { | |
236 | dev->power.request_pending = true; | |
237 | queue_work(pm_wq, &dev->power.work); | |
5e928f77 | 238 | } |
1bfee5bc | 239 | goto out; |
5e928f77 RW |
240 | } |
241 | ||
242 | dev->power.idle_notification = true; | |
243 | ||
564b905a RW |
244 | if (dev->pm_domain) |
245 | callback = dev->pm_domain->ops.runtime_idle; | |
4d27e9dc | 246 | else if (dev->type && dev->type->pm) |
71c63122 RW |
247 | callback = dev->type->pm->runtime_idle; |
248 | else if (dev->class && dev->class->pm) | |
249 | callback = dev->class->pm->runtime_idle; | |
9659cc06 RW |
250 | else if (dev->bus && dev->bus->pm) |
251 | callback = dev->bus->pm->runtime_idle; | |
71c63122 RW |
252 | else |
253 | callback = NULL; | |
a6ab7aa9 | 254 | |
ad3c36a5 RW |
255 | if (callback) |
256 | __rpm_callback(callback, dev); | |
5e928f77 RW |
257 | |
258 | dev->power.idle_notification = false; | |
259 | wake_up_all(&dev->power.wait_queue); | |
260 | ||
261 | out: | |
c3dc2f14 | 262 | trace_rpm_return_int(dev, _THIS_IP_, retval); |
5e928f77 RW |
263 | return retval; |
264 | } | |
265 | ||
71c63122 RW |
266 | /** |
267 | * rpm_callback - Run a given runtime PM callback for a given device. | |
268 | * @cb: Runtime PM callback to run. | |
269 | * @dev: Device to run the callback for. | |
270 | */ | |
271 | static int rpm_callback(int (*cb)(struct device *), struct device *dev) | |
71c63122 RW |
272 | { |
273 | int retval; | |
274 | ||
275 | if (!cb) | |
276 | return -ENOSYS; | |
277 | ||
ad3c36a5 | 278 | retval = __rpm_callback(cb, dev); |
71c63122 | 279 | |
71c63122 | 280 | dev->power.runtime_error = retval; |
632e270e | 281 | return retval != -EACCES ? retval : -EIO; |
71c63122 RW |
282 | } |
283 | ||
5e928f77 | 284 | /** |
62052ab1 | 285 | * rpm_suspend - Carry out runtime suspend of given device. |
5e928f77 | 286 | * @dev: Device to suspend. |
3f9af051 | 287 | * @rpmflags: Flag bits. |
5e928f77 | 288 | * |
62052ab1 | 289 | * Check if the device's runtime PM status allows it to be suspended. If |
1bfee5bc AS |
290 | * another suspend has been started earlier, either return immediately or wait |
291 | * for it to finish, depending on the RPM_NOWAIT and RPM_ASYNC flags. Cancel a | |
292 | * pending idle notification. If the RPM_ASYNC flag is set then queue a | |
293 | * suspend request; otherwise run the ->runtime_suspend() callback directly. | |
294 | * If a deferred resume was requested while the callback was running then carry | |
295 | * it out; otherwise send an idle notification for the device (if the suspend | |
296 | * failed) or for its parent (if the suspend succeeded). | |
5e928f77 RW |
297 | * |
298 | * This function must be called under dev->power.lock with interrupts disabled. | |
299 | */ | |
140a6c94 | 300 | static int rpm_suspend(struct device *dev, int rpmflags) |
5e928f77 RW |
301 | __releases(&dev->power.lock) __acquires(&dev->power.lock) |
302 | { | |
71c63122 | 303 | int (*callback)(struct device *); |
5e928f77 | 304 | struct device *parent = NULL; |
1bfee5bc | 305 | int retval; |
5e928f77 | 306 | |
c3dc2f14 | 307 | trace_rpm_suspend(dev, rpmflags); |
5e928f77 RW |
308 | |
309 | repeat: | |
1bfee5bc | 310 | retval = rpm_check_suspend_allowed(dev); |
5e928f77 | 311 | |
1bfee5bc AS |
312 | if (retval < 0) |
313 | ; /* Conditions are wrong. */ | |
314 | ||
315 | /* Synchronous suspends are not allowed in the RPM_RESUMING state. */ | |
316 | else if (dev->power.runtime_status == RPM_RESUMING && | |
317 | !(rpmflags & RPM_ASYNC)) | |
5e928f77 | 318 | retval = -EAGAIN; |
1bfee5bc | 319 | if (retval) |
5e928f77 | 320 | goto out; |
5e928f77 | 321 | |
15bcb91d AS |
322 | /* If the autosuspend_delay time hasn't expired yet, reschedule. */ |
323 | if ((rpmflags & RPM_AUTO) | |
324 | && dev->power.runtime_status != RPM_SUSPENDING) { | |
325 | unsigned long expires = pm_runtime_autosuspend_expiration(dev); | |
326 | ||
327 | if (expires != 0) { | |
328 | /* Pending requests need to be canceled. */ | |
329 | dev->power.request = RPM_REQ_NONE; | |
330 | ||
331 | /* | |
332 | * Optimization: If the timer is already running and is | |
333 | * set to expire at or before the autosuspend delay, | |
334 | * avoid the overhead of resetting it. Just let it | |
335 | * expire; pm_suspend_timer_fn() will take care of the | |
336 | * rest. | |
337 | */ | |
338 | if (!(dev->power.timer_expires && time_before_eq( | |
339 | dev->power.timer_expires, expires))) { | |
340 | dev->power.timer_expires = expires; | |
341 | mod_timer(&dev->power.suspend_timer, expires); | |
342 | } | |
343 | dev->power.timer_autosuspends = 1; | |
344 | goto out; | |
345 | } | |
346 | } | |
347 | ||
5e928f77 RW |
348 | /* Other scheduled or pending requests need to be canceled. */ |
349 | pm_runtime_cancel_pending(dev); | |
350 | ||
5e928f77 RW |
351 | if (dev->power.runtime_status == RPM_SUSPENDING) { |
352 | DEFINE_WAIT(wait); | |
353 | ||
1bfee5bc | 354 | if (rpmflags & (RPM_ASYNC | RPM_NOWAIT)) { |
5e928f77 RW |
355 | retval = -EINPROGRESS; |
356 | goto out; | |
357 | } | |
358 | ||
ad3c36a5 RW |
359 | if (dev->power.irq_safe) { |
360 | spin_unlock(&dev->power.lock); | |
361 | ||
362 | cpu_relax(); | |
363 | ||
364 | spin_lock(&dev->power.lock); | |
365 | goto repeat; | |
366 | } | |
367 | ||
5e928f77 RW |
368 | /* Wait for the other suspend running in parallel with us. */ |
369 | for (;;) { | |
370 | prepare_to_wait(&dev->power.wait_queue, &wait, | |
371 | TASK_UNINTERRUPTIBLE); | |
372 | if (dev->power.runtime_status != RPM_SUSPENDING) | |
373 | break; | |
374 | ||
375 | spin_unlock_irq(&dev->power.lock); | |
376 | ||
377 | schedule(); | |
378 | ||
379 | spin_lock_irq(&dev->power.lock); | |
380 | } | |
381 | finish_wait(&dev->power.wait_queue, &wait); | |
382 | goto repeat; | |
383 | } | |
384 | ||
7490e442 AS |
385 | dev->power.deferred_resume = false; |
386 | if (dev->power.no_callbacks) | |
387 | goto no_callback; /* Assume success. */ | |
388 | ||
1bfee5bc AS |
389 | /* Carry out an asynchronous or a synchronous suspend. */ |
390 | if (rpmflags & RPM_ASYNC) { | |
15bcb91d AS |
391 | dev->power.request = (rpmflags & RPM_AUTO) ? |
392 | RPM_REQ_AUTOSUSPEND : RPM_REQ_SUSPEND; | |
1bfee5bc AS |
393 | if (!dev->power.request_pending) { |
394 | dev->power.request_pending = true; | |
395 | queue_work(pm_wq, &dev->power.work); | |
396 | } | |
397 | goto out; | |
398 | } | |
399 | ||
8d4b9d1b | 400 | __update_runtime_status(dev, RPM_SUSPENDING); |
5e928f77 | 401 | |
564b905a RW |
402 | if (dev->pm_domain) |
403 | callback = dev->pm_domain->ops.runtime_suspend; | |
4d27e9dc | 404 | else if (dev->type && dev->type->pm) |
71c63122 RW |
405 | callback = dev->type->pm->runtime_suspend; |
406 | else if (dev->class && dev->class->pm) | |
407 | callback = dev->class->pm->runtime_suspend; | |
9659cc06 RW |
408 | else if (dev->bus && dev->bus->pm) |
409 | callback = dev->bus->pm->runtime_suspend; | |
71c63122 RW |
410 | else |
411 | callback = NULL; | |
5e928f77 | 412 | |
71c63122 | 413 | retval = rpm_callback(callback, dev); |
5e928f77 | 414 | if (retval) { |
8d4b9d1b | 415 | __update_runtime_status(dev, RPM_ACTIVE); |
2cffff12 | 416 | dev->power.deferred_resume = false; |
f71648d7 | 417 | if (retval == -EAGAIN || retval == -EBUSY) |
5e928f77 | 418 | dev->power.runtime_error = 0; |
f71648d7 | 419 | else |
240c7337 | 420 | pm_runtime_cancel_pending(dev); |
5e928f77 | 421 | } else { |
7490e442 | 422 | no_callback: |
8d4b9d1b | 423 | __update_runtime_status(dev, RPM_SUSPENDED); |
240c7337 | 424 | pm_runtime_deactivate_timer(dev); |
5e928f77 RW |
425 | |
426 | if (dev->parent) { | |
427 | parent = dev->parent; | |
428 | atomic_add_unless(&parent->power.child_count, -1, 0); | |
429 | } | |
430 | } | |
431 | wake_up_all(&dev->power.wait_queue); | |
432 | ||
433 | if (dev->power.deferred_resume) { | |
140a6c94 | 434 | rpm_resume(dev, 0); |
5e928f77 RW |
435 | retval = -EAGAIN; |
436 | goto out; | |
437 | } | |
438 | ||
c3810c88 | 439 | /* Maybe the parent is now able to suspend. */ |
c7b61de5 | 440 | if (parent && !parent->power.ignore_children && !dev->power.irq_safe) { |
c3810c88 | 441 | spin_unlock(&dev->power.lock); |
5e928f77 | 442 | |
c3810c88 AS |
443 | spin_lock(&parent->power.lock); |
444 | rpm_idle(parent, RPM_ASYNC); | |
445 | spin_unlock(&parent->power.lock); | |
5e928f77 | 446 | |
c3810c88 | 447 | spin_lock(&dev->power.lock); |
5e928f77 RW |
448 | } |
449 | ||
450 | out: | |
c3dc2f14 | 451 | trace_rpm_return_int(dev, _THIS_IP_, retval); |
5e928f77 RW |
452 | |
453 | return retval; | |
454 | } | |
455 | ||
456 | /** | |
62052ab1 | 457 | * rpm_resume - Carry out runtime resume of given device. |
5e928f77 | 458 | * @dev: Device to resume. |
3f9af051 | 459 | * @rpmflags: Flag bits. |
5e928f77 | 460 | * |
62052ab1 | 461 | * Check if the device's runtime PM status allows it to be resumed. Cancel |
1bfee5bc | 462 | * any scheduled or pending requests. If another resume has been started |
25985edc | 463 | * earlier, either return immediately or wait for it to finish, depending on the |
1bfee5bc AS |
464 | * RPM_NOWAIT and RPM_ASYNC flags. Similarly, if there's a suspend running in |
465 | * parallel with this function, either tell the other process to resume after | |
466 | * suspending (deferred_resume) or wait for it to finish. If the RPM_ASYNC | |
467 | * flag is set then queue a resume request; otherwise run the | |
468 | * ->runtime_resume() callback directly. Queue an idle notification for the | |
469 | * device if the resume succeeded. | |
5e928f77 RW |
470 | * |
471 | * This function must be called under dev->power.lock with interrupts disabled. | |
472 | */ | |
140a6c94 | 473 | static int rpm_resume(struct device *dev, int rpmflags) |
5e928f77 RW |
474 | __releases(&dev->power.lock) __acquires(&dev->power.lock) |
475 | { | |
71c63122 | 476 | int (*callback)(struct device *); |
5e928f77 RW |
477 | struct device *parent = NULL; |
478 | int retval = 0; | |
479 | ||
c3dc2f14 | 480 | trace_rpm_resume(dev, rpmflags); |
5e928f77 RW |
481 | |
482 | repeat: | |
1bfee5bc | 483 | if (dev->power.runtime_error) |
5e928f77 | 484 | retval = -EINVAL; |
1bfee5bc | 485 | else if (dev->power.disable_depth > 0) |
632e270e | 486 | retval = -EACCES; |
1bfee5bc | 487 | if (retval) |
5e928f77 | 488 | goto out; |
5e928f77 | 489 | |
15bcb91d AS |
490 | /* |
491 | * Other scheduled or pending requests need to be canceled. Small | |
492 | * optimization: If an autosuspend timer is running, leave it running | |
493 | * rather than cancelling it now only to restart it again in the near | |
494 | * future. | |
495 | */ | |
496 | dev->power.request = RPM_REQ_NONE; | |
497 | if (!dev->power.timer_autosuspends) | |
498 | pm_runtime_deactivate_timer(dev); | |
5e928f77 | 499 | |
1bfee5bc | 500 | if (dev->power.runtime_status == RPM_ACTIVE) { |
5e928f77 | 501 | retval = 1; |
5e928f77 | 502 | goto out; |
1bfee5bc | 503 | } |
5e928f77 RW |
504 | |
505 | if (dev->power.runtime_status == RPM_RESUMING | |
506 | || dev->power.runtime_status == RPM_SUSPENDING) { | |
507 | DEFINE_WAIT(wait); | |
508 | ||
1bfee5bc | 509 | if (rpmflags & (RPM_ASYNC | RPM_NOWAIT)) { |
5e928f77 RW |
510 | if (dev->power.runtime_status == RPM_SUSPENDING) |
511 | dev->power.deferred_resume = true; | |
1bfee5bc AS |
512 | else |
513 | retval = -EINPROGRESS; | |
5e928f77 RW |
514 | goto out; |
515 | } | |
516 | ||
ad3c36a5 RW |
517 | if (dev->power.irq_safe) { |
518 | spin_unlock(&dev->power.lock); | |
519 | ||
520 | cpu_relax(); | |
521 | ||
522 | spin_lock(&dev->power.lock); | |
523 | goto repeat; | |
524 | } | |
525 | ||
5e928f77 RW |
526 | /* Wait for the operation carried out in parallel with us. */ |
527 | for (;;) { | |
528 | prepare_to_wait(&dev->power.wait_queue, &wait, | |
529 | TASK_UNINTERRUPTIBLE); | |
530 | if (dev->power.runtime_status != RPM_RESUMING | |
531 | && dev->power.runtime_status != RPM_SUSPENDING) | |
532 | break; | |
533 | ||
534 | spin_unlock_irq(&dev->power.lock); | |
535 | ||
536 | schedule(); | |
537 | ||
538 | spin_lock_irq(&dev->power.lock); | |
539 | } | |
540 | finish_wait(&dev->power.wait_queue, &wait); | |
541 | goto repeat; | |
542 | } | |
543 | ||
7490e442 AS |
544 | /* |
545 | * See if we can skip waking up the parent. This is safe only if | |
546 | * power.no_callbacks is set, because otherwise we don't know whether | |
547 | * the resume will actually succeed. | |
548 | */ | |
549 | if (dev->power.no_callbacks && !parent && dev->parent) { | |
d63be5f9 | 550 | spin_lock_nested(&dev->parent->power.lock, SINGLE_DEPTH_NESTING); |
7490e442 AS |
551 | if (dev->parent->power.disable_depth > 0 |
552 | || dev->parent->power.ignore_children | |
553 | || dev->parent->power.runtime_status == RPM_ACTIVE) { | |
554 | atomic_inc(&dev->parent->power.child_count); | |
555 | spin_unlock(&dev->parent->power.lock); | |
556 | goto no_callback; /* Assume success. */ | |
557 | } | |
558 | spin_unlock(&dev->parent->power.lock); | |
559 | } | |
560 | ||
1bfee5bc AS |
561 | /* Carry out an asynchronous or a synchronous resume. */ |
562 | if (rpmflags & RPM_ASYNC) { | |
563 | dev->power.request = RPM_REQ_RESUME; | |
564 | if (!dev->power.request_pending) { | |
565 | dev->power.request_pending = true; | |
566 | queue_work(pm_wq, &dev->power.work); | |
567 | } | |
568 | retval = 0; | |
569 | goto out; | |
570 | } | |
571 | ||
5e928f77 RW |
572 | if (!parent && dev->parent) { |
573 | /* | |
c7b61de5 AS |
574 | * Increment the parent's usage counter and resume it if |
575 | * necessary. Not needed if dev is irq-safe; then the | |
576 | * parent is permanently resumed. | |
5e928f77 RW |
577 | */ |
578 | parent = dev->parent; | |
c7b61de5 AS |
579 | if (dev->power.irq_safe) |
580 | goto skip_parent; | |
862f89b3 | 581 | spin_unlock(&dev->power.lock); |
5e928f77 RW |
582 | |
583 | pm_runtime_get_noresume(parent); | |
584 | ||
862f89b3 | 585 | spin_lock(&parent->power.lock); |
5e928f77 | 586 | /* |
62052ab1 | 587 | * We can resume if the parent's runtime PM is disabled or it |
5e928f77 RW |
588 | * is set to ignore children. |
589 | */ | |
590 | if (!parent->power.disable_depth | |
591 | && !parent->power.ignore_children) { | |
140a6c94 | 592 | rpm_resume(parent, 0); |
5e928f77 RW |
593 | if (parent->power.runtime_status != RPM_ACTIVE) |
594 | retval = -EBUSY; | |
595 | } | |
862f89b3 | 596 | spin_unlock(&parent->power.lock); |
5e928f77 | 597 | |
862f89b3 | 598 | spin_lock(&dev->power.lock); |
5e928f77 RW |
599 | if (retval) |
600 | goto out; | |
601 | goto repeat; | |
602 | } | |
c7b61de5 | 603 | skip_parent: |
5e928f77 | 604 | |
7490e442 AS |
605 | if (dev->power.no_callbacks) |
606 | goto no_callback; /* Assume success. */ | |
607 | ||
8d4b9d1b | 608 | __update_runtime_status(dev, RPM_RESUMING); |
5e928f77 | 609 | |
564b905a RW |
610 | if (dev->pm_domain) |
611 | callback = dev->pm_domain->ops.runtime_resume; | |
4d27e9dc | 612 | else if (dev->type && dev->type->pm) |
71c63122 RW |
613 | callback = dev->type->pm->runtime_resume; |
614 | else if (dev->class && dev->class->pm) | |
615 | callback = dev->class->pm->runtime_resume; | |
9659cc06 RW |
616 | else if (dev->bus && dev->bus->pm) |
617 | callback = dev->bus->pm->runtime_resume; | |
71c63122 RW |
618 | else |
619 | callback = NULL; | |
5e928f77 | 620 | |
71c63122 | 621 | retval = rpm_callback(callback, dev); |
5e928f77 | 622 | if (retval) { |
8d4b9d1b | 623 | __update_runtime_status(dev, RPM_SUSPENDED); |
5e928f77 RW |
624 | pm_runtime_cancel_pending(dev); |
625 | } else { | |
7490e442 | 626 | no_callback: |
8d4b9d1b | 627 | __update_runtime_status(dev, RPM_ACTIVE); |
5e928f77 RW |
628 | if (parent) |
629 | atomic_inc(&parent->power.child_count); | |
630 | } | |
631 | wake_up_all(&dev->power.wait_queue); | |
632 | ||
633 | if (!retval) | |
140a6c94 | 634 | rpm_idle(dev, RPM_ASYNC); |
5e928f77 RW |
635 | |
636 | out: | |
c7b61de5 | 637 | if (parent && !dev->power.irq_safe) { |
5e928f77 RW |
638 | spin_unlock_irq(&dev->power.lock); |
639 | ||
640 | pm_runtime_put(parent); | |
641 | ||
642 | spin_lock_irq(&dev->power.lock); | |
643 | } | |
644 | ||
c3dc2f14 | 645 | trace_rpm_return_int(dev, _THIS_IP_, retval); |
5e928f77 RW |
646 | |
647 | return retval; | |
648 | } | |
649 | ||
5e928f77 | 650 | /** |
62052ab1 | 651 | * pm_runtime_work - Universal runtime PM work function. |
5e928f77 RW |
652 | * @work: Work structure used for scheduling the execution of this function. |
653 | * | |
654 | * Use @work to get the device object the work is to be done for, determine what | |
62052ab1 | 655 | * is to be done and execute the appropriate runtime PM function. |
5e928f77 RW |
656 | */ |
657 | static void pm_runtime_work(struct work_struct *work) | |
658 | { | |
659 | struct device *dev = container_of(work, struct device, power.work); | |
660 | enum rpm_request req; | |
661 | ||
662 | spin_lock_irq(&dev->power.lock); | |
663 | ||
664 | if (!dev->power.request_pending) | |
665 | goto out; | |
666 | ||
667 | req = dev->power.request; | |
668 | dev->power.request = RPM_REQ_NONE; | |
669 | dev->power.request_pending = false; | |
670 | ||
671 | switch (req) { | |
672 | case RPM_REQ_NONE: | |
673 | break; | |
674 | case RPM_REQ_IDLE: | |
140a6c94 | 675 | rpm_idle(dev, RPM_NOWAIT); |
5e928f77 RW |
676 | break; |
677 | case RPM_REQ_SUSPEND: | |
140a6c94 | 678 | rpm_suspend(dev, RPM_NOWAIT); |
5e928f77 | 679 | break; |
15bcb91d AS |
680 | case RPM_REQ_AUTOSUSPEND: |
681 | rpm_suspend(dev, RPM_NOWAIT | RPM_AUTO); | |
682 | break; | |
5e928f77 | 683 | case RPM_REQ_RESUME: |
140a6c94 | 684 | rpm_resume(dev, RPM_NOWAIT); |
5e928f77 RW |
685 | break; |
686 | } | |
687 | ||
688 | out: | |
689 | spin_unlock_irq(&dev->power.lock); | |
690 | } | |
691 | ||
5e928f77 RW |
692 | /** |
693 | * pm_suspend_timer_fn - Timer function for pm_schedule_suspend(). | |
694 | * @data: Device pointer passed by pm_schedule_suspend(). | |
695 | * | |
1bfee5bc | 696 | * Check if the time is right and queue a suspend request. |
5e928f77 RW |
697 | */ |
698 | static void pm_suspend_timer_fn(unsigned long data) | |
699 | { | |
700 | struct device *dev = (struct device *)data; | |
701 | unsigned long flags; | |
702 | unsigned long expires; | |
703 | ||
704 | spin_lock_irqsave(&dev->power.lock, flags); | |
705 | ||
706 | expires = dev->power.timer_expires; | |
707 | /* If 'expire' is after 'jiffies' we've been called too early. */ | |
708 | if (expires > 0 && !time_after(expires, jiffies)) { | |
709 | dev->power.timer_expires = 0; | |
15bcb91d AS |
710 | rpm_suspend(dev, dev->power.timer_autosuspends ? |
711 | (RPM_ASYNC | RPM_AUTO) : RPM_ASYNC); | |
5e928f77 RW |
712 | } |
713 | ||
714 | spin_unlock_irqrestore(&dev->power.lock, flags); | |
715 | } | |
716 | ||
717 | /** | |
718 | * pm_schedule_suspend - Set up a timer to submit a suspend request in future. | |
719 | * @dev: Device to suspend. | |
720 | * @delay: Time to wait before submitting a suspend request, in milliseconds. | |
721 | */ | |
722 | int pm_schedule_suspend(struct device *dev, unsigned int delay) | |
723 | { | |
724 | unsigned long flags; | |
1bfee5bc | 725 | int retval; |
5e928f77 RW |
726 | |
727 | spin_lock_irqsave(&dev->power.lock, flags); | |
728 | ||
5e928f77 | 729 | if (!delay) { |
140a6c94 | 730 | retval = rpm_suspend(dev, RPM_ASYNC); |
5e928f77 RW |
731 | goto out; |
732 | } | |
733 | ||
1bfee5bc | 734 | retval = rpm_check_suspend_allowed(dev); |
5e928f77 RW |
735 | if (retval) |
736 | goto out; | |
737 | ||
1bfee5bc AS |
738 | /* Other scheduled or pending requests need to be canceled. */ |
739 | pm_runtime_cancel_pending(dev); | |
740 | ||
5e928f77 | 741 | dev->power.timer_expires = jiffies + msecs_to_jiffies(delay); |
1bfee5bc | 742 | dev->power.timer_expires += !dev->power.timer_expires; |
15bcb91d | 743 | dev->power.timer_autosuspends = 0; |
5e928f77 RW |
744 | mod_timer(&dev->power.suspend_timer, dev->power.timer_expires); |
745 | ||
746 | out: | |
747 | spin_unlock_irqrestore(&dev->power.lock, flags); | |
748 | ||
749 | return retval; | |
750 | } | |
751 | EXPORT_SYMBOL_GPL(pm_schedule_suspend); | |
752 | ||
5e928f77 | 753 | /** |
62052ab1 | 754 | * __pm_runtime_idle - Entry point for runtime idle operations. |
140a6c94 AS |
755 | * @dev: Device to send idle notification for. |
756 | * @rpmflags: Flag bits. | |
757 | * | |
758 | * If the RPM_GET_PUT flag is set, decrement the device's usage count and | |
759 | * return immediately if it is larger than zero. Then carry out an idle | |
760 | * notification, either synchronous or asynchronous. | |
761 | * | |
311aab73 CC |
762 | * This routine may be called in atomic context if the RPM_ASYNC flag is set, |
763 | * or if pm_runtime_irq_safe() has been called. | |
5e928f77 | 764 | */ |
140a6c94 | 765 | int __pm_runtime_idle(struct device *dev, int rpmflags) |
5e928f77 RW |
766 | { |
767 | unsigned long flags; | |
768 | int retval; | |
769 | ||
311aab73 CC |
770 | might_sleep_if(!(rpmflags & RPM_ASYNC) && !dev->power.irq_safe); |
771 | ||
140a6c94 AS |
772 | if (rpmflags & RPM_GET_PUT) { |
773 | if (!atomic_dec_and_test(&dev->power.usage_count)) | |
774 | return 0; | |
775 | } | |
776 | ||
5e928f77 | 777 | spin_lock_irqsave(&dev->power.lock, flags); |
140a6c94 | 778 | retval = rpm_idle(dev, rpmflags); |
5e928f77 RW |
779 | spin_unlock_irqrestore(&dev->power.lock, flags); |
780 | ||
781 | return retval; | |
782 | } | |
140a6c94 | 783 | EXPORT_SYMBOL_GPL(__pm_runtime_idle); |
5e928f77 RW |
784 | |
785 | /** | |
62052ab1 | 786 | * __pm_runtime_suspend - Entry point for runtime put/suspend operations. |
140a6c94 | 787 | * @dev: Device to suspend. |
3f9af051 | 788 | * @rpmflags: Flag bits. |
5e928f77 | 789 | * |
15bcb91d AS |
790 | * If the RPM_GET_PUT flag is set, decrement the device's usage count and |
791 | * return immediately if it is larger than zero. Then carry out a suspend, | |
792 | * either synchronous or asynchronous. | |
140a6c94 | 793 | * |
311aab73 CC |
794 | * This routine may be called in atomic context if the RPM_ASYNC flag is set, |
795 | * or if pm_runtime_irq_safe() has been called. | |
5e928f77 | 796 | */ |
140a6c94 | 797 | int __pm_runtime_suspend(struct device *dev, int rpmflags) |
5e928f77 | 798 | { |
140a6c94 | 799 | unsigned long flags; |
1d531c14 | 800 | int retval; |
5e928f77 | 801 | |
311aab73 CC |
802 | might_sleep_if(!(rpmflags & RPM_ASYNC) && !dev->power.irq_safe); |
803 | ||
15bcb91d AS |
804 | if (rpmflags & RPM_GET_PUT) { |
805 | if (!atomic_dec_and_test(&dev->power.usage_count)) | |
806 | return 0; | |
807 | } | |
808 | ||
140a6c94 AS |
809 | spin_lock_irqsave(&dev->power.lock, flags); |
810 | retval = rpm_suspend(dev, rpmflags); | |
811 | spin_unlock_irqrestore(&dev->power.lock, flags); | |
5e928f77 RW |
812 | |
813 | return retval; | |
814 | } | |
140a6c94 | 815 | EXPORT_SYMBOL_GPL(__pm_runtime_suspend); |
5e928f77 RW |
816 | |
817 | /** | |
62052ab1 | 818 | * __pm_runtime_resume - Entry point for runtime resume operations. |
140a6c94 | 819 | * @dev: Device to resume. |
3f9af051 | 820 | * @rpmflags: Flag bits. |
5e928f77 | 821 | * |
140a6c94 AS |
822 | * If the RPM_GET_PUT flag is set, increment the device's usage count. Then |
823 | * carry out a resume, either synchronous or asynchronous. | |
824 | * | |
311aab73 CC |
825 | * This routine may be called in atomic context if the RPM_ASYNC flag is set, |
826 | * or if pm_runtime_irq_safe() has been called. | |
5e928f77 | 827 | */ |
140a6c94 | 828 | int __pm_runtime_resume(struct device *dev, int rpmflags) |
5e928f77 | 829 | { |
140a6c94 AS |
830 | unsigned long flags; |
831 | int retval; | |
5e928f77 | 832 | |
311aab73 CC |
833 | might_sleep_if(!(rpmflags & RPM_ASYNC) && !dev->power.irq_safe); |
834 | ||
140a6c94 AS |
835 | if (rpmflags & RPM_GET_PUT) |
836 | atomic_inc(&dev->power.usage_count); | |
837 | ||
838 | spin_lock_irqsave(&dev->power.lock, flags); | |
839 | retval = rpm_resume(dev, rpmflags); | |
840 | spin_unlock_irqrestore(&dev->power.lock, flags); | |
5e928f77 RW |
841 | |
842 | return retval; | |
843 | } | |
140a6c94 | 844 | EXPORT_SYMBOL_GPL(__pm_runtime_resume); |
5e928f77 RW |
845 | |
846 | /** | |
62052ab1 | 847 | * __pm_runtime_set_status - Set runtime PM status of a device. |
5e928f77 | 848 | * @dev: Device to handle. |
62052ab1 | 849 | * @status: New runtime PM status of the device. |
5e928f77 | 850 | * |
62052ab1 | 851 | * If runtime PM of the device is disabled or its power.runtime_error field is |
5e928f77 RW |
852 | * different from zero, the status may be changed either to RPM_ACTIVE, or to |
853 | * RPM_SUSPENDED, as long as that reflects the actual state of the device. | |
854 | * However, if the device has a parent and the parent is not active, and the | |
855 | * parent's power.ignore_children flag is unset, the device's status cannot be | |
856 | * set to RPM_ACTIVE, so -EBUSY is returned in that case. | |
857 | * | |
858 | * If successful, __pm_runtime_set_status() clears the power.runtime_error field | |
859 | * and the device parent's counter of unsuspended children is modified to | |
860 | * reflect the new status. If the new status is RPM_SUSPENDED, an idle | |
861 | * notification request for the parent is submitted. | |
862 | */ | |
863 | int __pm_runtime_set_status(struct device *dev, unsigned int status) | |
864 | { | |
865 | struct device *parent = dev->parent; | |
866 | unsigned long flags; | |
867 | bool notify_parent = false; | |
868 | int error = 0; | |
869 | ||
870 | if (status != RPM_ACTIVE && status != RPM_SUSPENDED) | |
871 | return -EINVAL; | |
872 | ||
873 | spin_lock_irqsave(&dev->power.lock, flags); | |
874 | ||
875 | if (!dev->power.runtime_error && !dev->power.disable_depth) { | |
876 | error = -EAGAIN; | |
877 | goto out; | |
878 | } | |
879 | ||
880 | if (dev->power.runtime_status == status) | |
881 | goto out_set; | |
882 | ||
883 | if (status == RPM_SUSPENDED) { | |
884 | /* It always is possible to set the status to 'suspended'. */ | |
885 | if (parent) { | |
886 | atomic_add_unless(&parent->power.child_count, -1, 0); | |
887 | notify_parent = !parent->power.ignore_children; | |
888 | } | |
889 | goto out_set; | |
890 | } | |
891 | ||
892 | if (parent) { | |
bab636b9 | 893 | spin_lock_nested(&parent->power.lock, SINGLE_DEPTH_NESTING); |
5e928f77 RW |
894 | |
895 | /* | |
896 | * It is invalid to put an active child under a parent that is | |
62052ab1 | 897 | * not active, has runtime PM enabled and the |
5e928f77 RW |
898 | * 'power.ignore_children' flag unset. |
899 | */ | |
900 | if (!parent->power.disable_depth | |
901 | && !parent->power.ignore_children | |
965c4ac0 | 902 | && parent->power.runtime_status != RPM_ACTIVE) |
5e928f77 | 903 | error = -EBUSY; |
965c4ac0 RW |
904 | else if (dev->power.runtime_status == RPM_SUSPENDED) |
905 | atomic_inc(&parent->power.child_count); | |
5e928f77 | 906 | |
862f89b3 | 907 | spin_unlock(&parent->power.lock); |
5e928f77 RW |
908 | |
909 | if (error) | |
910 | goto out; | |
911 | } | |
912 | ||
913 | out_set: | |
8d4b9d1b | 914 | __update_runtime_status(dev, status); |
5e928f77 RW |
915 | dev->power.runtime_error = 0; |
916 | out: | |
917 | spin_unlock_irqrestore(&dev->power.lock, flags); | |
918 | ||
919 | if (notify_parent) | |
920 | pm_request_idle(parent); | |
921 | ||
922 | return error; | |
923 | } | |
924 | EXPORT_SYMBOL_GPL(__pm_runtime_set_status); | |
925 | ||
926 | /** | |
927 | * __pm_runtime_barrier - Cancel pending requests and wait for completions. | |
928 | * @dev: Device to handle. | |
929 | * | |
930 | * Flush all pending requests for the device from pm_wq and wait for all | |
62052ab1 | 931 | * runtime PM operations involving the device in progress to complete. |
5e928f77 RW |
932 | * |
933 | * Should be called under dev->power.lock with interrupts disabled. | |
934 | */ | |
935 | static void __pm_runtime_barrier(struct device *dev) | |
936 | { | |
937 | pm_runtime_deactivate_timer(dev); | |
938 | ||
939 | if (dev->power.request_pending) { | |
940 | dev->power.request = RPM_REQ_NONE; | |
941 | spin_unlock_irq(&dev->power.lock); | |
942 | ||
943 | cancel_work_sync(&dev->power.work); | |
944 | ||
945 | spin_lock_irq(&dev->power.lock); | |
946 | dev->power.request_pending = false; | |
947 | } | |
948 | ||
949 | if (dev->power.runtime_status == RPM_SUSPENDING | |
950 | || dev->power.runtime_status == RPM_RESUMING | |
951 | || dev->power.idle_notification) { | |
952 | DEFINE_WAIT(wait); | |
953 | ||
954 | /* Suspend, wake-up or idle notification in progress. */ | |
955 | for (;;) { | |
956 | prepare_to_wait(&dev->power.wait_queue, &wait, | |
957 | TASK_UNINTERRUPTIBLE); | |
958 | if (dev->power.runtime_status != RPM_SUSPENDING | |
959 | && dev->power.runtime_status != RPM_RESUMING | |
960 | && !dev->power.idle_notification) | |
961 | break; | |
962 | spin_unlock_irq(&dev->power.lock); | |
963 | ||
964 | schedule(); | |
965 | ||
966 | spin_lock_irq(&dev->power.lock); | |
967 | } | |
968 | finish_wait(&dev->power.wait_queue, &wait); | |
969 | } | |
970 | } | |
971 | ||
972 | /** | |
973 | * pm_runtime_barrier - Flush pending requests and wait for completions. | |
974 | * @dev: Device to handle. | |
975 | * | |
976 | * Prevent the device from being suspended by incrementing its usage counter and | |
977 | * if there's a pending resume request for the device, wake the device up. | |
978 | * Next, make sure that all pending requests for the device have been flushed | |
62052ab1 | 979 | * from pm_wq and wait for all runtime PM operations involving the device in |
5e928f77 RW |
980 | * progress to complete. |
981 | * | |
982 | * Return value: | |
983 | * 1, if there was a resume request pending and the device had to be woken up, | |
984 | * 0, otherwise | |
985 | */ | |
986 | int pm_runtime_barrier(struct device *dev) | |
987 | { | |
988 | int retval = 0; | |
989 | ||
990 | pm_runtime_get_noresume(dev); | |
991 | spin_lock_irq(&dev->power.lock); | |
992 | ||
993 | if (dev->power.request_pending | |
994 | && dev->power.request == RPM_REQ_RESUME) { | |
140a6c94 | 995 | rpm_resume(dev, 0); |
5e928f77 RW |
996 | retval = 1; |
997 | } | |
998 | ||
999 | __pm_runtime_barrier(dev); | |
1000 | ||
1001 | spin_unlock_irq(&dev->power.lock); | |
1002 | pm_runtime_put_noidle(dev); | |
1003 | ||
1004 | return retval; | |
1005 | } | |
1006 | EXPORT_SYMBOL_GPL(pm_runtime_barrier); | |
1007 | ||
1008 | /** | |
62052ab1 | 1009 | * __pm_runtime_disable - Disable runtime PM of a device. |
5e928f77 RW |
1010 | * @dev: Device to handle. |
1011 | * @check_resume: If set, check if there's a resume request for the device. | |
1012 | * | |
1013 | * Increment power.disable_depth for the device and if was zero previously, | |
62052ab1 | 1014 | * cancel all pending runtime PM requests for the device and wait for all |
5e928f77 | 1015 | * operations in progress to complete. The device can be either active or |
62052ab1 | 1016 | * suspended after its runtime PM has been disabled. |
5e928f77 RW |
1017 | * |
1018 | * If @check_resume is set and there's a resume request pending when | |
1019 | * __pm_runtime_disable() is called and power.disable_depth is zero, the | |
62052ab1 | 1020 | * function will wake up the device before disabling its runtime PM. |
5e928f77 RW |
1021 | */ |
1022 | void __pm_runtime_disable(struct device *dev, bool check_resume) | |
1023 | { | |
1024 | spin_lock_irq(&dev->power.lock); | |
1025 | ||
1026 | if (dev->power.disable_depth > 0) { | |
1027 | dev->power.disable_depth++; | |
1028 | goto out; | |
1029 | } | |
1030 | ||
1031 | /* | |
1032 | * Wake up the device if there's a resume request pending, because that | |
62052ab1 | 1033 | * means there probably is some I/O to process and disabling runtime PM |
5e928f77 RW |
1034 | * shouldn't prevent the device from processing the I/O. |
1035 | */ | |
1036 | if (check_resume && dev->power.request_pending | |
1037 | && dev->power.request == RPM_REQ_RESUME) { | |
1038 | /* | |
1039 | * Prevent suspends and idle notifications from being carried | |
1040 | * out after we have woken up the device. | |
1041 | */ | |
1042 | pm_runtime_get_noresume(dev); | |
1043 | ||
140a6c94 | 1044 | rpm_resume(dev, 0); |
5e928f77 RW |
1045 | |
1046 | pm_runtime_put_noidle(dev); | |
1047 | } | |
1048 | ||
1049 | if (!dev->power.disable_depth++) | |
1050 | __pm_runtime_barrier(dev); | |
1051 | ||
1052 | out: | |
1053 | spin_unlock_irq(&dev->power.lock); | |
1054 | } | |
1055 | EXPORT_SYMBOL_GPL(__pm_runtime_disable); | |
1056 | ||
1057 | /** | |
62052ab1 | 1058 | * pm_runtime_enable - Enable runtime PM of a device. |
5e928f77 RW |
1059 | * @dev: Device to handle. |
1060 | */ | |
1061 | void pm_runtime_enable(struct device *dev) | |
1062 | { | |
1063 | unsigned long flags; | |
1064 | ||
1065 | spin_lock_irqsave(&dev->power.lock, flags); | |
1066 | ||
1067 | if (dev->power.disable_depth > 0) | |
1068 | dev->power.disable_depth--; | |
1069 | else | |
1070 | dev_warn(dev, "Unbalanced %s!\n", __func__); | |
1071 | ||
1072 | spin_unlock_irqrestore(&dev->power.lock, flags); | |
1073 | } | |
1074 | EXPORT_SYMBOL_GPL(pm_runtime_enable); | |
1075 | ||
53823639 | 1076 | /** |
62052ab1 | 1077 | * pm_runtime_forbid - Block runtime PM of a device. |
53823639 RW |
1078 | * @dev: Device to handle. |
1079 | * | |
1080 | * Increase the device's usage count and clear its power.runtime_auto flag, | |
1081 | * so that it cannot be suspended at run time until pm_runtime_allow() is called | |
1082 | * for it. | |
1083 | */ | |
1084 | void pm_runtime_forbid(struct device *dev) | |
1085 | { | |
1086 | spin_lock_irq(&dev->power.lock); | |
1087 | if (!dev->power.runtime_auto) | |
1088 | goto out; | |
1089 | ||
1090 | dev->power.runtime_auto = false; | |
1091 | atomic_inc(&dev->power.usage_count); | |
140a6c94 | 1092 | rpm_resume(dev, 0); |
53823639 RW |
1093 | |
1094 | out: | |
1095 | spin_unlock_irq(&dev->power.lock); | |
1096 | } | |
1097 | EXPORT_SYMBOL_GPL(pm_runtime_forbid); | |
1098 | ||
1099 | /** | |
62052ab1 | 1100 | * pm_runtime_allow - Unblock runtime PM of a device. |
53823639 RW |
1101 | * @dev: Device to handle. |
1102 | * | |
1103 | * Decrease the device's usage count and set its power.runtime_auto flag. | |
1104 | */ | |
1105 | void pm_runtime_allow(struct device *dev) | |
1106 | { | |
1107 | spin_lock_irq(&dev->power.lock); | |
1108 | if (dev->power.runtime_auto) | |
1109 | goto out; | |
1110 | ||
1111 | dev->power.runtime_auto = true; | |
1112 | if (atomic_dec_and_test(&dev->power.usage_count)) | |
15bcb91d | 1113 | rpm_idle(dev, RPM_AUTO); |
53823639 RW |
1114 | |
1115 | out: | |
1116 | spin_unlock_irq(&dev->power.lock); | |
1117 | } | |
1118 | EXPORT_SYMBOL_GPL(pm_runtime_allow); | |
1119 | ||
7490e442 | 1120 | /** |
62052ab1 | 1121 | * pm_runtime_no_callbacks - Ignore runtime PM callbacks for a device. |
7490e442 AS |
1122 | * @dev: Device to handle. |
1123 | * | |
1124 | * Set the power.no_callbacks flag, which tells the PM core that this | |
62052ab1 RW |
1125 | * device is power-managed through its parent and has no runtime PM |
1126 | * callbacks of its own. The runtime sysfs attributes will be removed. | |
7490e442 AS |
1127 | */ |
1128 | void pm_runtime_no_callbacks(struct device *dev) | |
1129 | { | |
1130 | spin_lock_irq(&dev->power.lock); | |
1131 | dev->power.no_callbacks = 1; | |
1132 | spin_unlock_irq(&dev->power.lock); | |
1133 | if (device_is_registered(dev)) | |
1134 | rpm_sysfs_remove(dev); | |
1135 | } | |
1136 | EXPORT_SYMBOL_GPL(pm_runtime_no_callbacks); | |
1137 | ||
c7b61de5 AS |
1138 | /** |
1139 | * pm_runtime_irq_safe - Leave interrupts disabled during callbacks. | |
1140 | * @dev: Device to handle | |
1141 | * | |
1142 | * Set the power.irq_safe flag, which tells the PM core that the | |
1143 | * ->runtime_suspend() and ->runtime_resume() callbacks for this device should | |
1144 | * always be invoked with the spinlock held and interrupts disabled. It also | |
1145 | * causes the parent's usage counter to be permanently incremented, preventing | |
1146 | * the parent from runtime suspending -- otherwise an irq-safe child might have | |
1147 | * to wait for a non-irq-safe parent. | |
1148 | */ | |
1149 | void pm_runtime_irq_safe(struct device *dev) | |
1150 | { | |
1151 | if (dev->parent) | |
1152 | pm_runtime_get_sync(dev->parent); | |
1153 | spin_lock_irq(&dev->power.lock); | |
1154 | dev->power.irq_safe = 1; | |
1155 | spin_unlock_irq(&dev->power.lock); | |
1156 | } | |
1157 | EXPORT_SYMBOL_GPL(pm_runtime_irq_safe); | |
1158 | ||
15bcb91d AS |
1159 | /** |
1160 | * update_autosuspend - Handle a change to a device's autosuspend settings. | |
1161 | * @dev: Device to handle. | |
1162 | * @old_delay: The former autosuspend_delay value. | |
1163 | * @old_use: The former use_autosuspend value. | |
1164 | * | |
1165 | * Prevent runtime suspend if the new delay is negative and use_autosuspend is | |
1166 | * set; otherwise allow it. Send an idle notification if suspends are allowed. | |
1167 | * | |
1168 | * This function must be called under dev->power.lock with interrupts disabled. | |
1169 | */ | |
1170 | static void update_autosuspend(struct device *dev, int old_delay, int old_use) | |
1171 | { | |
1172 | int delay = dev->power.autosuspend_delay; | |
1173 | ||
1174 | /* Should runtime suspend be prevented now? */ | |
1175 | if (dev->power.use_autosuspend && delay < 0) { | |
1176 | ||
1177 | /* If it used to be allowed then prevent it. */ | |
1178 | if (!old_use || old_delay >= 0) { | |
1179 | atomic_inc(&dev->power.usage_count); | |
1180 | rpm_resume(dev, 0); | |
1181 | } | |
1182 | } | |
1183 | ||
1184 | /* Runtime suspend should be allowed now. */ | |
1185 | else { | |
1186 | ||
1187 | /* If it used to be prevented then allow it. */ | |
1188 | if (old_use && old_delay < 0) | |
1189 | atomic_dec(&dev->power.usage_count); | |
1190 | ||
1191 | /* Maybe we can autosuspend now. */ | |
1192 | rpm_idle(dev, RPM_AUTO); | |
1193 | } | |
1194 | } | |
1195 | ||
1196 | /** | |
1197 | * pm_runtime_set_autosuspend_delay - Set a device's autosuspend_delay value. | |
1198 | * @dev: Device to handle. | |
1199 | * @delay: Value of the new delay in milliseconds. | |
1200 | * | |
1201 | * Set the device's power.autosuspend_delay value. If it changes to negative | |
62052ab1 RW |
1202 | * and the power.use_autosuspend flag is set, prevent runtime suspends. If it |
1203 | * changes the other way, allow runtime suspends. | |
15bcb91d AS |
1204 | */ |
1205 | void pm_runtime_set_autosuspend_delay(struct device *dev, int delay) | |
1206 | { | |
1207 | int old_delay, old_use; | |
1208 | ||
1209 | spin_lock_irq(&dev->power.lock); | |
1210 | old_delay = dev->power.autosuspend_delay; | |
1211 | old_use = dev->power.use_autosuspend; | |
1212 | dev->power.autosuspend_delay = delay; | |
1213 | update_autosuspend(dev, old_delay, old_use); | |
1214 | spin_unlock_irq(&dev->power.lock); | |
1215 | } | |
1216 | EXPORT_SYMBOL_GPL(pm_runtime_set_autosuspend_delay); | |
1217 | ||
1218 | /** | |
1219 | * __pm_runtime_use_autosuspend - Set a device's use_autosuspend flag. | |
1220 | * @dev: Device to handle. | |
1221 | * @use: New value for use_autosuspend. | |
1222 | * | |
62052ab1 | 1223 | * Set the device's power.use_autosuspend flag, and allow or prevent runtime |
15bcb91d AS |
1224 | * suspends as needed. |
1225 | */ | |
1226 | void __pm_runtime_use_autosuspend(struct device *dev, bool use) | |
1227 | { | |
1228 | int old_delay, old_use; | |
1229 | ||
1230 | spin_lock_irq(&dev->power.lock); | |
1231 | old_delay = dev->power.autosuspend_delay; | |
1232 | old_use = dev->power.use_autosuspend; | |
1233 | dev->power.use_autosuspend = use; | |
1234 | update_autosuspend(dev, old_delay, old_use); | |
1235 | spin_unlock_irq(&dev->power.lock); | |
1236 | } | |
1237 | EXPORT_SYMBOL_GPL(__pm_runtime_use_autosuspend); | |
1238 | ||
5e928f77 | 1239 | /** |
62052ab1 | 1240 | * pm_runtime_init - Initialize runtime PM fields in given device object. |
5e928f77 RW |
1241 | * @dev: Device object to initialize. |
1242 | */ | |
1243 | void pm_runtime_init(struct device *dev) | |
1244 | { | |
5e928f77 RW |
1245 | dev->power.runtime_status = RPM_SUSPENDED; |
1246 | dev->power.idle_notification = false; | |
1247 | ||
1248 | dev->power.disable_depth = 1; | |
1249 | atomic_set(&dev->power.usage_count, 0); | |
1250 | ||
1251 | dev->power.runtime_error = 0; | |
1252 | ||
1253 | atomic_set(&dev->power.child_count, 0); | |
1254 | pm_suspend_ignore_children(dev, false); | |
53823639 | 1255 | dev->power.runtime_auto = true; |
5e928f77 RW |
1256 | |
1257 | dev->power.request_pending = false; | |
1258 | dev->power.request = RPM_REQ_NONE; | |
1259 | dev->power.deferred_resume = false; | |
8d4b9d1b | 1260 | dev->power.accounting_timestamp = jiffies; |
5e928f77 RW |
1261 | INIT_WORK(&dev->power.work, pm_runtime_work); |
1262 | ||
1263 | dev->power.timer_expires = 0; | |
1264 | setup_timer(&dev->power.suspend_timer, pm_suspend_timer_fn, | |
1265 | (unsigned long)dev); | |
1266 | ||
1267 | init_waitqueue_head(&dev->power.wait_queue); | |
1268 | } | |
1269 | ||
1270 | /** | |
1271 | * pm_runtime_remove - Prepare for removing a device from device hierarchy. | |
1272 | * @dev: Device object being removed from device hierarchy. | |
1273 | */ | |
1274 | void pm_runtime_remove(struct device *dev) | |
1275 | { | |
1276 | __pm_runtime_disable(dev, false); | |
1277 | ||
1278 | /* Change the status back to 'suspended' to match the initial status. */ | |
1279 | if (dev->power.runtime_status == RPM_ACTIVE) | |
1280 | pm_runtime_set_suspended(dev); | |
c7b61de5 AS |
1281 | if (dev->power.irq_safe && dev->parent) |
1282 | pm_runtime_put_sync(dev->parent); | |
5e928f77 | 1283 | } |