Merge branch 'pm-cpufreq'
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / acpi / device_pm.c
1 /*
2 * drivers/acpi/device_pm.c - ACPI device power management routines.
3 *
4 * Copyright (C) 2012, Intel Corp.
5 * Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
6 *
7 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as published
11 * by the Free Software Foundation.
12 *
13 * This program is distributed in the hope that it will be useful, but
14 * WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License along
19 * with this program; if not, write to the Free Software Foundation, Inc.,
20 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
21 *
22 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
23 */
24
25 #include <linux/device.h>
26 #include <linux/export.h>
27 #include <linux/mutex.h>
28 #include <linux/pm_qos.h>
29 #include <linux/pm_runtime.h>
30
31 #include <acpi/acpi.h>
32 #include <acpi/acpi_bus.h>
33 #include <acpi/acpi_drivers.h>
34
35 #include "internal.h"
36
37 #define _COMPONENT ACPI_POWER_COMPONENT
38 ACPI_MODULE_NAME("device_pm");
39
40 static DEFINE_MUTEX(acpi_pm_notifier_lock);
41
42 /**
43 * acpi_add_pm_notifier - Register PM notifier for given ACPI device.
44 * @adev: ACPI device to add the notifier for.
45 * @context: Context information to pass to the notifier routine.
46 *
47 * NOTE: @adev need not be a run-wake or wakeup device to be a valid source of
48 * PM wakeup events. For example, wakeup events may be generated for bridges
49 * if one of the devices below the bridge is signaling wakeup, even if the
50 * bridge itself doesn't have a wakeup GPE associated with it.
51 */
52 acpi_status acpi_add_pm_notifier(struct acpi_device *adev,
53 acpi_notify_handler handler, void *context)
54 {
55 acpi_status status = AE_ALREADY_EXISTS;
56
57 mutex_lock(&acpi_pm_notifier_lock);
58
59 if (adev->wakeup.flags.notifier_present)
60 goto out;
61
62 status = acpi_install_notify_handler(adev->handle,
63 ACPI_SYSTEM_NOTIFY,
64 handler, context);
65 if (ACPI_FAILURE(status))
66 goto out;
67
68 adev->wakeup.flags.notifier_present = true;
69
70 out:
71 mutex_unlock(&acpi_pm_notifier_lock);
72 return status;
73 }
74
75 /**
76 * acpi_remove_pm_notifier - Unregister PM notifier from given ACPI device.
77 * @adev: ACPI device to remove the notifier from.
78 */
79 acpi_status acpi_remove_pm_notifier(struct acpi_device *adev,
80 acpi_notify_handler handler)
81 {
82 acpi_status status = AE_BAD_PARAMETER;
83
84 mutex_lock(&acpi_pm_notifier_lock);
85
86 if (!adev->wakeup.flags.notifier_present)
87 goto out;
88
89 status = acpi_remove_notify_handler(adev->handle,
90 ACPI_SYSTEM_NOTIFY,
91 handler);
92 if (ACPI_FAILURE(status))
93 goto out;
94
95 adev->wakeup.flags.notifier_present = false;
96
97 out:
98 mutex_unlock(&acpi_pm_notifier_lock);
99 return status;
100 }
101
102 /**
103 * acpi_power_state_string - String representation of ACPI device power state.
104 * @state: ACPI device power state to return the string representation of.
105 */
106 const char *acpi_power_state_string(int state)
107 {
108 switch (state) {
109 case ACPI_STATE_D0:
110 return "D0";
111 case ACPI_STATE_D1:
112 return "D1";
113 case ACPI_STATE_D2:
114 return "D2";
115 case ACPI_STATE_D3_HOT:
116 return "D3hot";
117 case ACPI_STATE_D3_COLD:
118 return "D3cold";
119 default:
120 return "(unknown)";
121 }
122 }
123
124 /**
125 * acpi_device_get_power - Get power state of an ACPI device.
126 * @device: Device to get the power state of.
127 * @state: Place to store the power state of the device.
128 *
129 * This function does not update the device's power.state field, but it may
130 * update its parent's power.state field (when the parent's power state is
131 * unknown and the device's power state turns out to be D0).
132 */
133 int acpi_device_get_power(struct acpi_device *device, int *state)
134 {
135 int result = ACPI_STATE_UNKNOWN;
136
137 if (!device || !state)
138 return -EINVAL;
139
140 if (!device->flags.power_manageable) {
141 /* TBD: Non-recursive algorithm for walking up hierarchy. */
142 *state = device->parent ?
143 device->parent->power.state : ACPI_STATE_D0;
144 goto out;
145 }
146
147 /*
148 * Get the device's power state either directly (via _PSC) or
149 * indirectly (via power resources).
150 */
151 if (device->power.flags.explicit_get) {
152 unsigned long long psc;
153 acpi_status status = acpi_evaluate_integer(device->handle,
154 "_PSC", NULL, &psc);
155 if (ACPI_FAILURE(status))
156 return -ENODEV;
157
158 result = psc;
159 }
160 /* The test below covers ACPI_STATE_UNKNOWN too. */
161 if (result <= ACPI_STATE_D2) {
162 ; /* Do nothing. */
163 } else if (device->power.flags.power_resources) {
164 int error = acpi_power_get_inferred_state(device, &result);
165 if (error)
166 return error;
167 } else if (result == ACPI_STATE_D3_HOT) {
168 result = ACPI_STATE_D3;
169 }
170
171 /*
172 * If we were unsure about the device parent's power state up to this
173 * point, the fact that the device is in D0 implies that the parent has
174 * to be in D0 too.
175 */
176 if (device->parent && device->parent->power.state == ACPI_STATE_UNKNOWN
177 && result == ACPI_STATE_D0)
178 device->parent->power.state = ACPI_STATE_D0;
179
180 *state = result;
181
182 out:
183 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] power state is %s\n",
184 device->pnp.bus_id, acpi_power_state_string(*state)));
185
186 return 0;
187 }
188
189 static int acpi_dev_pm_explicit_set(struct acpi_device *adev, int state)
190 {
191 if (adev->power.states[state].flags.explicit_set) {
192 char method[5] = { '_', 'P', 'S', '0' + state, '\0' };
193 acpi_status status;
194
195 status = acpi_evaluate_object(adev->handle, method, NULL, NULL);
196 if (ACPI_FAILURE(status))
197 return -ENODEV;
198 }
199 return 0;
200 }
201
202 /**
203 * acpi_device_set_power - Set power state of an ACPI device.
204 * @device: Device to set the power state of.
205 * @state: New power state to set.
206 *
207 * Callers must ensure that the device is power manageable before using this
208 * function.
209 */
210 int acpi_device_set_power(struct acpi_device *device, int state)
211 {
212 int result = 0;
213 bool cut_power = false;
214
215 if (!device || (state < ACPI_STATE_D0) || (state > ACPI_STATE_D3_COLD))
216 return -EINVAL;
217
218 /* Make sure this is a valid target state */
219
220 if (state == device->power.state) {
221 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device is already at %s\n",
222 acpi_power_state_string(state)));
223 return 0;
224 }
225
226 if (!device->power.states[state].flags.valid) {
227 printk(KERN_WARNING PREFIX "Device does not support %s\n",
228 acpi_power_state_string(state));
229 return -ENODEV;
230 }
231 if (device->parent && (state < device->parent->power.state)) {
232 printk(KERN_WARNING PREFIX
233 "Cannot set device to a higher-powered"
234 " state than parent\n");
235 return -ENODEV;
236 }
237
238 /* For D3cold we should first transition into D3hot. */
239 if (state == ACPI_STATE_D3_COLD
240 && device->power.states[ACPI_STATE_D3_COLD].flags.os_accessible) {
241 state = ACPI_STATE_D3_HOT;
242 cut_power = true;
243 }
244
245 if (state < device->power.state && state != ACPI_STATE_D0
246 && device->power.state >= ACPI_STATE_D3_HOT) {
247 printk(KERN_WARNING PREFIX
248 "Cannot transition to non-D0 state from D3\n");
249 return -ENODEV;
250 }
251
252 /*
253 * Transition Power
254 * ----------------
255 * In accordance with the ACPI specification first apply power (via
256 * power resources) and then evalute _PSx.
257 */
258 if (device->power.flags.power_resources) {
259 result = acpi_power_transition(device, state);
260 if (result)
261 goto end;
262 }
263 result = acpi_dev_pm_explicit_set(device, state);
264 if (result)
265 goto end;
266
267 if (cut_power) {
268 device->power.state = state;
269 state = ACPI_STATE_D3_COLD;
270 result = acpi_power_transition(device, state);
271 }
272
273 end:
274 if (result) {
275 printk(KERN_WARNING PREFIX
276 "Device [%s] failed to transition to %s\n",
277 device->pnp.bus_id,
278 acpi_power_state_string(state));
279 } else {
280 device->power.state = state;
281 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
282 "Device [%s] transitioned to %s\n",
283 device->pnp.bus_id,
284 acpi_power_state_string(state)));
285 }
286
287 return result;
288 }
289 EXPORT_SYMBOL(acpi_device_set_power);
290
291 int acpi_bus_set_power(acpi_handle handle, int state)
292 {
293 struct acpi_device *device;
294 int result;
295
296 result = acpi_bus_get_device(handle, &device);
297 if (result)
298 return result;
299
300 if (!device->flags.power_manageable) {
301 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
302 "Device [%s] is not power manageable\n",
303 dev_name(&device->dev)));
304 return -ENODEV;
305 }
306
307 return acpi_device_set_power(device, state);
308 }
309 EXPORT_SYMBOL(acpi_bus_set_power);
310
311 int acpi_bus_init_power(struct acpi_device *device)
312 {
313 int state;
314 int result;
315
316 if (!device)
317 return -EINVAL;
318
319 device->power.state = ACPI_STATE_UNKNOWN;
320
321 result = acpi_device_get_power(device, &state);
322 if (result)
323 return result;
324
325 if (state < ACPI_STATE_D3_COLD && device->power.flags.power_resources) {
326 result = acpi_power_on_resources(device, state);
327 if (result)
328 return result;
329
330 result = acpi_dev_pm_explicit_set(device, state);
331 if (result)
332 return result;
333 } else if (state == ACPI_STATE_UNKNOWN) {
334 /* No power resources and missing _PSC? Try to force D0. */
335 state = ACPI_STATE_D0;
336 result = acpi_dev_pm_explicit_set(device, state);
337 if (result)
338 return result;
339 }
340 device->power.state = state;
341 return 0;
342 }
343
344 int acpi_bus_update_power(acpi_handle handle, int *state_p)
345 {
346 struct acpi_device *device;
347 int state;
348 int result;
349
350 result = acpi_bus_get_device(handle, &device);
351 if (result)
352 return result;
353
354 result = acpi_device_get_power(device, &state);
355 if (result)
356 return result;
357
358 if (state == ACPI_STATE_UNKNOWN)
359 state = ACPI_STATE_D0;
360
361 result = acpi_device_set_power(device, state);
362 if (!result && state_p)
363 *state_p = state;
364
365 return result;
366 }
367 EXPORT_SYMBOL_GPL(acpi_bus_update_power);
368
369 bool acpi_bus_power_manageable(acpi_handle handle)
370 {
371 struct acpi_device *device;
372 int result;
373
374 result = acpi_bus_get_device(handle, &device);
375 return result ? false : device->flags.power_manageable;
376 }
377 EXPORT_SYMBOL(acpi_bus_power_manageable);
378
379 bool acpi_bus_can_wakeup(acpi_handle handle)
380 {
381 struct acpi_device *device;
382 int result;
383
384 result = acpi_bus_get_device(handle, &device);
385 return result ? false : device->wakeup.flags.valid;
386 }
387 EXPORT_SYMBOL(acpi_bus_can_wakeup);
388
389 /**
390 * acpi_device_power_state - Get preferred power state of ACPI device.
391 * @dev: Device whose preferred target power state to return.
392 * @adev: ACPI device node corresponding to @dev.
393 * @target_state: System state to match the resultant device state.
394 * @d_max_in: Deepest low-power state to take into consideration.
395 * @d_min_p: Location to store the upper limit of the allowed states range.
396 * Return value: Preferred power state of the device on success, -ENODEV
397 * (if there's no 'struct acpi_device' for @dev) or -EINVAL on failure
398 *
399 * Find the lowest power (highest number) ACPI device power state that the
400 * device can be in while the system is in the state represented by
401 * @target_state. If @d_min_p is set, the highest power (lowest number) device
402 * power state that @dev can be in for the given system sleep state is stored
403 * at the location pointed to by it.
404 *
405 * Callers must ensure that @dev and @adev are valid pointers and that @adev
406 * actually corresponds to @dev before using this function.
407 */
408 int acpi_device_power_state(struct device *dev, struct acpi_device *adev,
409 u32 target_state, int d_max_in, int *d_min_p)
410 {
411 char acpi_method[] = "_SxD";
412 unsigned long long d_min, d_max;
413 bool wakeup = false;
414
415 if (d_max_in < ACPI_STATE_D0 || d_max_in > ACPI_STATE_D3)
416 return -EINVAL;
417
418 if (d_max_in > ACPI_STATE_D3_HOT) {
419 enum pm_qos_flags_status stat;
420
421 stat = dev_pm_qos_flags(dev, PM_QOS_FLAG_NO_POWER_OFF);
422 if (stat == PM_QOS_FLAGS_ALL)
423 d_max_in = ACPI_STATE_D3_HOT;
424 }
425
426 acpi_method[2] = '0' + target_state;
427 /*
428 * If the sleep state is S0, the lowest limit from ACPI is D3,
429 * but if the device has _S0W, we will use the value from _S0W
430 * as the lowest limit from ACPI. Finally, we will constrain
431 * the lowest limit with the specified one.
432 */
433 d_min = ACPI_STATE_D0;
434 d_max = ACPI_STATE_D3;
435
436 /*
437 * If present, _SxD methods return the minimum D-state (highest power
438 * state) we can use for the corresponding S-states. Otherwise, the
439 * minimum D-state is D0 (ACPI 3.x).
440 *
441 * NOTE: We rely on acpi_evaluate_integer() not clobbering the integer
442 * provided -- that's our fault recovery, we ignore retval.
443 */
444 if (target_state > ACPI_STATE_S0) {
445 acpi_evaluate_integer(adev->handle, acpi_method, NULL, &d_min);
446 wakeup = device_may_wakeup(dev) && adev->wakeup.flags.valid
447 && adev->wakeup.sleep_state >= target_state;
448 } else if (dev_pm_qos_flags(dev, PM_QOS_FLAG_REMOTE_WAKEUP) !=
449 PM_QOS_FLAGS_NONE) {
450 wakeup = adev->wakeup.flags.valid;
451 }
452
453 /*
454 * If _PRW says we can wake up the system from the target sleep state,
455 * the D-state returned by _SxD is sufficient for that (we assume a
456 * wakeup-aware driver if wake is set). Still, if _SxW exists
457 * (ACPI 3.x), it should return the maximum (lowest power) D-state that
458 * can wake the system. _S0W may be valid, too.
459 */
460 if (wakeup) {
461 acpi_status status;
462
463 acpi_method[3] = 'W';
464 status = acpi_evaluate_integer(adev->handle, acpi_method, NULL,
465 &d_max);
466 if (ACPI_FAILURE(status)) {
467 if (target_state != ACPI_STATE_S0 ||
468 status != AE_NOT_FOUND)
469 d_max = d_min;
470 } else if (d_max < d_min) {
471 /* Warn the user of the broken DSDT */
472 printk(KERN_WARNING "ACPI: Wrong value from %s\n",
473 acpi_method);
474 /* Sanitize it */
475 d_min = d_max;
476 }
477 }
478
479 if (d_max_in < d_min)
480 return -EINVAL;
481 if (d_min_p)
482 *d_min_p = d_min;
483 /* constrain d_max with specified lowest limit (max number) */
484 if (d_max > d_max_in) {
485 for (d_max = d_max_in; d_max > d_min; d_max--) {
486 if (adev->power.states[d_max].flags.valid)
487 break;
488 }
489 }
490 return d_max;
491 }
492 EXPORT_SYMBOL_GPL(acpi_device_power_state);
493
494 /**
495 * acpi_pm_device_sleep_state - Get preferred power state of ACPI device.
496 * @dev: Device whose preferred target power state to return.
497 * @d_min_p: Location to store the upper limit of the allowed states range.
498 * @d_max_in: Deepest low-power state to take into consideration.
499 * Return value: Preferred power state of the device on success, -ENODEV
500 * (if there's no 'struct acpi_device' for @dev) or -EINVAL on failure
501 *
502 * The caller must ensure that @dev is valid before using this function.
503 */
504 int acpi_pm_device_sleep_state(struct device *dev, int *d_min_p, int d_max_in)
505 {
506 acpi_handle handle = DEVICE_ACPI_HANDLE(dev);
507 struct acpi_device *adev;
508
509 if (!handle || acpi_bus_get_device(handle, &adev)) {
510 dev_dbg(dev, "ACPI handle without context in %s!\n", __func__);
511 return -ENODEV;
512 }
513
514 return acpi_device_power_state(dev, adev, acpi_target_system_state(),
515 d_max_in, d_min_p);
516 }
517 EXPORT_SYMBOL(acpi_pm_device_sleep_state);
518
519 #ifdef CONFIG_PM_RUNTIME
520 /**
521 * acpi_wakeup_device - Wakeup notification handler for ACPI devices.
522 * @handle: ACPI handle of the device the notification is for.
523 * @event: Type of the signaled event.
524 * @context: Device corresponding to @handle.
525 */
526 static void acpi_wakeup_device(acpi_handle handle, u32 event, void *context)
527 {
528 struct device *dev = context;
529
530 if (event == ACPI_NOTIFY_DEVICE_WAKE && dev) {
531 pm_wakeup_event(dev, 0);
532 pm_runtime_resume(dev);
533 }
534 }
535
536 /**
537 * __acpi_device_run_wake - Enable/disable runtime remote wakeup for device.
538 * @adev: ACPI device to enable/disable the remote wakeup for.
539 * @enable: Whether to enable or disable the wakeup functionality.
540 *
541 * Enable/disable the GPE associated with @adev so that it can generate
542 * wakeup signals for the device in response to external (remote) events and
543 * enable/disable device wakeup power.
544 *
545 * Callers must ensure that @adev is a valid ACPI device node before executing
546 * this function.
547 */
548 int __acpi_device_run_wake(struct acpi_device *adev, bool enable)
549 {
550 struct acpi_device_wakeup *wakeup = &adev->wakeup;
551
552 if (enable) {
553 acpi_status res;
554 int error;
555
556 error = acpi_enable_wakeup_device_power(adev, ACPI_STATE_S0);
557 if (error)
558 return error;
559
560 res = acpi_enable_gpe(wakeup->gpe_device, wakeup->gpe_number);
561 if (ACPI_FAILURE(res)) {
562 acpi_disable_wakeup_device_power(adev);
563 return -EIO;
564 }
565 } else {
566 acpi_disable_gpe(wakeup->gpe_device, wakeup->gpe_number);
567 acpi_disable_wakeup_device_power(adev);
568 }
569 return 0;
570 }
571
572 /**
573 * acpi_pm_device_run_wake - Enable/disable remote wakeup for given device.
574 * @dev: Device to enable/disable the platform to wake up.
575 * @enable: Whether to enable or disable the wakeup functionality.
576 */
577 int acpi_pm_device_run_wake(struct device *phys_dev, bool enable)
578 {
579 struct acpi_device *adev;
580 acpi_handle handle;
581
582 if (!device_run_wake(phys_dev))
583 return -EINVAL;
584
585 handle = DEVICE_ACPI_HANDLE(phys_dev);
586 if (!handle || acpi_bus_get_device(handle, &adev)) {
587 dev_dbg(phys_dev, "ACPI handle without context in %s!\n",
588 __func__);
589 return -ENODEV;
590 }
591
592 return __acpi_device_run_wake(adev, enable);
593 }
594 EXPORT_SYMBOL(acpi_pm_device_run_wake);
595 #else
596 static inline void acpi_wakeup_device(acpi_handle handle, u32 event,
597 void *context) {}
598 #endif /* CONFIG_PM_RUNTIME */
599
600 #ifdef CONFIG_PM_SLEEP
601 /**
602 * __acpi_device_sleep_wake - Enable or disable device to wake up the system.
603 * @dev: Device to enable/desible to wake up the system.
604 * @target_state: System state the device is supposed to wake up from.
605 * @enable: Whether to enable or disable @dev to wake up the system.
606 */
607 int __acpi_device_sleep_wake(struct acpi_device *adev, u32 target_state,
608 bool enable)
609 {
610 return enable ?
611 acpi_enable_wakeup_device_power(adev, target_state) :
612 acpi_disable_wakeup_device_power(adev);
613 }
614
615 /**
616 * acpi_pm_device_sleep_wake - Enable or disable device to wake up the system.
617 * @dev: Device to enable/desible to wake up the system from sleep states.
618 * @enable: Whether to enable or disable @dev to wake up the system.
619 */
620 int acpi_pm_device_sleep_wake(struct device *dev, bool enable)
621 {
622 acpi_handle handle;
623 struct acpi_device *adev;
624 int error;
625
626 if (!device_can_wakeup(dev))
627 return -EINVAL;
628
629 handle = DEVICE_ACPI_HANDLE(dev);
630 if (!handle || acpi_bus_get_device(handle, &adev)) {
631 dev_dbg(dev, "ACPI handle without context in %s!\n", __func__);
632 return -ENODEV;
633 }
634
635 error = __acpi_device_sleep_wake(adev, acpi_target_system_state(),
636 enable);
637 if (!error)
638 dev_info(dev, "System wakeup %s by ACPI\n",
639 enable ? "enabled" : "disabled");
640
641 return error;
642 }
643 #endif /* CONFIG_PM_SLEEP */
644
645 /**
646 * acpi_dev_pm_get_node - Get ACPI device node for the given physical device.
647 * @dev: Device to get the ACPI node for.
648 */
649 struct acpi_device *acpi_dev_pm_get_node(struct device *dev)
650 {
651 acpi_handle handle = DEVICE_ACPI_HANDLE(dev);
652 struct acpi_device *adev;
653
654 return handle && !acpi_bus_get_device(handle, &adev) ? adev : NULL;
655 }
656
657 /**
658 * acpi_dev_pm_low_power - Put ACPI device into a low-power state.
659 * @dev: Device to put into a low-power state.
660 * @adev: ACPI device node corresponding to @dev.
661 * @system_state: System state to choose the device state for.
662 */
663 static int acpi_dev_pm_low_power(struct device *dev, struct acpi_device *adev,
664 u32 system_state)
665 {
666 int power_state;
667
668 if (!acpi_device_power_manageable(adev))
669 return 0;
670
671 power_state = acpi_device_power_state(dev, adev, system_state,
672 ACPI_STATE_D3, NULL);
673 if (power_state < ACPI_STATE_D0 || power_state > ACPI_STATE_D3)
674 return -EIO;
675
676 return acpi_device_set_power(adev, power_state);
677 }
678
679 /**
680 * acpi_dev_pm_full_power - Put ACPI device into the full-power state.
681 * @adev: ACPI device node to put into the full-power state.
682 */
683 static int acpi_dev_pm_full_power(struct acpi_device *adev)
684 {
685 return acpi_device_power_manageable(adev) ?
686 acpi_device_set_power(adev, ACPI_STATE_D0) : 0;
687 }
688
689 #ifdef CONFIG_PM_RUNTIME
690 /**
691 * acpi_dev_runtime_suspend - Put device into a low-power state using ACPI.
692 * @dev: Device to put into a low-power state.
693 *
694 * Put the given device into a runtime low-power state using the standard ACPI
695 * mechanism. Set up remote wakeup if desired, choose the state to put the
696 * device into (this checks if remote wakeup is expected to work too), and set
697 * the power state of the device.
698 */
699 int acpi_dev_runtime_suspend(struct device *dev)
700 {
701 struct acpi_device *adev = acpi_dev_pm_get_node(dev);
702 bool remote_wakeup;
703 int error;
704
705 if (!adev)
706 return 0;
707
708 remote_wakeup = dev_pm_qos_flags(dev, PM_QOS_FLAG_REMOTE_WAKEUP) >
709 PM_QOS_FLAGS_NONE;
710 error = __acpi_device_run_wake(adev, remote_wakeup);
711 if (remote_wakeup && error)
712 return -EAGAIN;
713
714 error = acpi_dev_pm_low_power(dev, adev, ACPI_STATE_S0);
715 if (error)
716 __acpi_device_run_wake(adev, false);
717
718 return error;
719 }
720 EXPORT_SYMBOL_GPL(acpi_dev_runtime_suspend);
721
722 /**
723 * acpi_dev_runtime_resume - Put device into the full-power state using ACPI.
724 * @dev: Device to put into the full-power state.
725 *
726 * Put the given device into the full-power state using the standard ACPI
727 * mechanism at run time. Set the power state of the device to ACPI D0 and
728 * disable remote wakeup.
729 */
730 int acpi_dev_runtime_resume(struct device *dev)
731 {
732 struct acpi_device *adev = acpi_dev_pm_get_node(dev);
733 int error;
734
735 if (!adev)
736 return 0;
737
738 error = acpi_dev_pm_full_power(adev);
739 __acpi_device_run_wake(adev, false);
740 return error;
741 }
742 EXPORT_SYMBOL_GPL(acpi_dev_runtime_resume);
743
744 /**
745 * acpi_subsys_runtime_suspend - Suspend device using ACPI.
746 * @dev: Device to suspend.
747 *
748 * Carry out the generic runtime suspend procedure for @dev and use ACPI to put
749 * it into a runtime low-power state.
750 */
751 int acpi_subsys_runtime_suspend(struct device *dev)
752 {
753 int ret = pm_generic_runtime_suspend(dev);
754 return ret ? ret : acpi_dev_runtime_suspend(dev);
755 }
756 EXPORT_SYMBOL_GPL(acpi_subsys_runtime_suspend);
757
758 /**
759 * acpi_subsys_runtime_resume - Resume device using ACPI.
760 * @dev: Device to Resume.
761 *
762 * Use ACPI to put the given device into the full-power state and carry out the
763 * generic runtime resume procedure for it.
764 */
765 int acpi_subsys_runtime_resume(struct device *dev)
766 {
767 int ret = acpi_dev_runtime_resume(dev);
768 return ret ? ret : pm_generic_runtime_resume(dev);
769 }
770 EXPORT_SYMBOL_GPL(acpi_subsys_runtime_resume);
771 #endif /* CONFIG_PM_RUNTIME */
772
773 #ifdef CONFIG_PM_SLEEP
774 /**
775 * acpi_dev_suspend_late - Put device into a low-power state using ACPI.
776 * @dev: Device to put into a low-power state.
777 *
778 * Put the given device into a low-power state during system transition to a
779 * sleep state using the standard ACPI mechanism. Set up system wakeup if
780 * desired, choose the state to put the device into (this checks if system
781 * wakeup is expected to work too), and set the power state of the device.
782 */
783 int acpi_dev_suspend_late(struct device *dev)
784 {
785 struct acpi_device *adev = acpi_dev_pm_get_node(dev);
786 u32 target_state;
787 bool wakeup;
788 int error;
789
790 if (!adev)
791 return 0;
792
793 target_state = acpi_target_system_state();
794 wakeup = device_may_wakeup(dev);
795 error = __acpi_device_sleep_wake(adev, target_state, wakeup);
796 if (wakeup && error)
797 return error;
798
799 error = acpi_dev_pm_low_power(dev, adev, target_state);
800 if (error)
801 __acpi_device_sleep_wake(adev, ACPI_STATE_UNKNOWN, false);
802
803 return error;
804 }
805 EXPORT_SYMBOL_GPL(acpi_dev_suspend_late);
806
807 /**
808 * acpi_dev_resume_early - Put device into the full-power state using ACPI.
809 * @dev: Device to put into the full-power state.
810 *
811 * Put the given device into the full-power state using the standard ACPI
812 * mechanism during system transition to the working state. Set the power
813 * state of the device to ACPI D0 and disable remote wakeup.
814 */
815 int acpi_dev_resume_early(struct device *dev)
816 {
817 struct acpi_device *adev = acpi_dev_pm_get_node(dev);
818 int error;
819
820 if (!adev)
821 return 0;
822
823 error = acpi_dev_pm_full_power(adev);
824 __acpi_device_sleep_wake(adev, ACPI_STATE_UNKNOWN, false);
825 return error;
826 }
827 EXPORT_SYMBOL_GPL(acpi_dev_resume_early);
828
829 /**
830 * acpi_subsys_prepare - Prepare device for system transition to a sleep state.
831 * @dev: Device to prepare.
832 */
833 int acpi_subsys_prepare(struct device *dev)
834 {
835 /*
836 * Follow PCI and resume devices suspended at run time before running
837 * their system suspend callbacks.
838 */
839 pm_runtime_resume(dev);
840 return pm_generic_prepare(dev);
841 }
842 EXPORT_SYMBOL_GPL(acpi_subsys_prepare);
843
844 /**
845 * acpi_subsys_suspend_late - Suspend device using ACPI.
846 * @dev: Device to suspend.
847 *
848 * Carry out the generic late suspend procedure for @dev and use ACPI to put
849 * it into a low-power state during system transition into a sleep state.
850 */
851 int acpi_subsys_suspend_late(struct device *dev)
852 {
853 int ret = pm_generic_suspend_late(dev);
854 return ret ? ret : acpi_dev_suspend_late(dev);
855 }
856 EXPORT_SYMBOL_GPL(acpi_subsys_suspend_late);
857
858 /**
859 * acpi_subsys_resume_early - Resume device using ACPI.
860 * @dev: Device to Resume.
861 *
862 * Use ACPI to put the given device into the full-power state and carry out the
863 * generic early resume procedure for it during system transition into the
864 * working state.
865 */
866 int acpi_subsys_resume_early(struct device *dev)
867 {
868 int ret = acpi_dev_resume_early(dev);
869 return ret ? ret : pm_generic_resume_early(dev);
870 }
871 EXPORT_SYMBOL_GPL(acpi_subsys_resume_early);
872 #endif /* CONFIG_PM_SLEEP */
873
874 static struct dev_pm_domain acpi_general_pm_domain = {
875 .ops = {
876 #ifdef CONFIG_PM_RUNTIME
877 .runtime_suspend = acpi_subsys_runtime_suspend,
878 .runtime_resume = acpi_subsys_runtime_resume,
879 .runtime_idle = pm_generic_runtime_idle,
880 #endif
881 #ifdef CONFIG_PM_SLEEP
882 .prepare = acpi_subsys_prepare,
883 .suspend_late = acpi_subsys_suspend_late,
884 .resume_early = acpi_subsys_resume_early,
885 .poweroff_late = acpi_subsys_suspend_late,
886 .restore_early = acpi_subsys_resume_early,
887 #endif
888 },
889 };
890
891 /**
892 * acpi_dev_pm_attach - Prepare device for ACPI power management.
893 * @dev: Device to prepare.
894 * @power_on: Whether or not to power on the device.
895 *
896 * If @dev has a valid ACPI handle that has a valid struct acpi_device object
897 * attached to it, install a wakeup notification handler for the device and
898 * add it to the general ACPI PM domain. If @power_on is set, the device will
899 * be put into the ACPI D0 state before the function returns.
900 *
901 * This assumes that the @dev's bus type uses generic power management callbacks
902 * (or doesn't use any power management callbacks at all).
903 *
904 * Callers must ensure proper synchronization of this function with power
905 * management callbacks.
906 */
907 int acpi_dev_pm_attach(struct device *dev, bool power_on)
908 {
909 struct acpi_device *adev = acpi_dev_pm_get_node(dev);
910
911 if (!adev)
912 return -ENODEV;
913
914 if (dev->pm_domain)
915 return -EEXIST;
916
917 acpi_add_pm_notifier(adev, acpi_wakeup_device, dev);
918 dev->pm_domain = &acpi_general_pm_domain;
919 if (power_on) {
920 acpi_dev_pm_full_power(adev);
921 __acpi_device_run_wake(adev, false);
922 }
923 return 0;
924 }
925 EXPORT_SYMBOL_GPL(acpi_dev_pm_attach);
926
927 /**
928 * acpi_dev_pm_detach - Remove ACPI power management from the device.
929 * @dev: Device to take care of.
930 * @power_off: Whether or not to try to remove power from the device.
931 *
932 * Remove the device from the general ACPI PM domain and remove its wakeup
933 * notifier. If @power_off is set, additionally remove power from the device if
934 * possible.
935 *
936 * Callers must ensure proper synchronization of this function with power
937 * management callbacks.
938 */
939 void acpi_dev_pm_detach(struct device *dev, bool power_off)
940 {
941 struct acpi_device *adev = acpi_dev_pm_get_node(dev);
942
943 if (adev && dev->pm_domain == &acpi_general_pm_domain) {
944 dev->pm_domain = NULL;
945 acpi_remove_pm_notifier(adev, acpi_wakeup_device);
946 if (power_off) {
947 /*
948 * If the device's PM QoS resume latency limit or flags
949 * have been exposed to user space, they have to be
950 * hidden at this point, so that they don't affect the
951 * choice of the low-power state to put the device into.
952 */
953 dev_pm_qos_hide_latency_limit(dev);
954 dev_pm_qos_hide_flags(dev);
955 __acpi_device_run_wake(adev, false);
956 acpi_dev_pm_low_power(dev, adev, ACPI_STATE_S0);
957 }
958 }
959 }
960 EXPORT_SYMBOL_GPL(acpi_dev_pm_detach);
961
962 /**
963 * acpi_dev_pm_add_dependent - Add physical device depending for PM.
964 * @handle: Handle of ACPI device node.
965 * @depdev: Device depending on that node for PM.
966 */
967 void acpi_dev_pm_add_dependent(acpi_handle handle, struct device *depdev)
968 {
969 struct acpi_device_physical_node *dep;
970 struct acpi_device *adev;
971
972 if (!depdev || acpi_bus_get_device(handle, &adev))
973 return;
974
975 mutex_lock(&adev->physical_node_lock);
976
977 list_for_each_entry(dep, &adev->power_dependent, node)
978 if (dep->dev == depdev)
979 goto out;
980
981 dep = kzalloc(sizeof(*dep), GFP_KERNEL);
982 if (dep) {
983 dep->dev = depdev;
984 list_add_tail(&dep->node, &adev->power_dependent);
985 }
986
987 out:
988 mutex_unlock(&adev->physical_node_lock);
989 }
990 EXPORT_SYMBOL_GPL(acpi_dev_pm_add_dependent);
991
992 /**
993 * acpi_dev_pm_remove_dependent - Remove physical device depending for PM.
994 * @handle: Handle of ACPI device node.
995 * @depdev: Device depending on that node for PM.
996 */
997 void acpi_dev_pm_remove_dependent(acpi_handle handle, struct device *depdev)
998 {
999 struct acpi_device_physical_node *dep;
1000 struct acpi_device *adev;
1001
1002 if (!depdev || acpi_bus_get_device(handle, &adev))
1003 return;
1004
1005 mutex_lock(&adev->physical_node_lock);
1006
1007 list_for_each_entry(dep, &adev->power_dependent, node)
1008 if (dep->dev == depdev) {
1009 list_del(&dep->node);
1010 kfree(dep);
1011 break;
1012 }
1013
1014 mutex_unlock(&adev->physical_node_lock);
1015 }
1016 EXPORT_SYMBOL_GPL(acpi_dev_pm_remove_dependent);