2 * drivers/acpi/device_pm.c - ACPI device power management routines.
4 * Copyright (C) 2012, Intel Corp.
5 * Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
7 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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.
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.
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.
22 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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>
31 #include <acpi/acpi.h>
32 #include <acpi/acpi_bus.h>
33 #include <acpi/acpi_drivers.h>
37 #define _COMPONENT ACPI_POWER_COMPONENT
38 ACPI_MODULE_NAME("device_pm");
40 static DEFINE_MUTEX(acpi_pm_notifier_lock);
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.
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.
52 acpi_status acpi_add_pm_notifier(struct acpi_device *adev,
53 acpi_notify_handler handler, void *context)
55 acpi_status status = AE_ALREADY_EXISTS;
57 mutex_lock(&acpi_pm_notifier_lock);
59 if (adev->wakeup.flags.notifier_present)
62 status = acpi_install_notify_handler(adev->handle,
65 if (ACPI_FAILURE(status))
68 adev->wakeup.flags.notifier_present = true;
71 mutex_unlock(&acpi_pm_notifier_lock);
76 * acpi_remove_pm_notifier - Unregister PM notifier from given ACPI device.
77 * @adev: ACPI device to remove the notifier from.
79 acpi_status acpi_remove_pm_notifier(struct acpi_device *adev,
80 acpi_notify_handler handler)
82 acpi_status status = AE_BAD_PARAMETER;
84 mutex_lock(&acpi_pm_notifier_lock);
86 if (!adev->wakeup.flags.notifier_present)
89 status = acpi_remove_notify_handler(adev->handle,
92 if (ACPI_FAILURE(status))
95 adev->wakeup.flags.notifier_present = false;
98 mutex_unlock(&acpi_pm_notifier_lock);
103 * acpi_power_state_string - String representation of ACPI device power state.
104 * @state: ACPI device power state to return the string representation of.
106 const char *acpi_power_state_string(int state)
115 case ACPI_STATE_D3_HOT:
117 case ACPI_STATE_D3_COLD:
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.
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).
133 int acpi_device_get_power(struct acpi_device *device, int *state)
135 int result = ACPI_STATE_UNKNOWN;
137 if (!device || !state)
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;
148 * Get the device's power state either directly (via _PSC) or
149 * indirectly (via power resources).
151 if (device->power.flags.explicit_get) {
152 unsigned long long psc;
153 acpi_status status = acpi_evaluate_integer(device->handle,
155 if (ACPI_FAILURE(status))
160 /* The test below covers ACPI_STATE_UNKNOWN too. */
161 if (result <= ACPI_STATE_D2) {
163 } else if (device->power.flags.power_resources) {
164 int error = acpi_power_get_inferred_state(device, &result);
167 } else if (result == ACPI_STATE_D3_HOT) {
168 result = ACPI_STATE_D3;
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
176 if (device->parent && device->parent->power.state == ACPI_STATE_UNKNOWN
177 && result == ACPI_STATE_D0)
178 device->parent->power.state = ACPI_STATE_D0;
183 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] power state is %s\n",
184 device->pnp.bus_id, acpi_power_state_string(*state)));
189 static int acpi_dev_pm_explicit_set(struct acpi_device *adev, int state)
191 if (adev->power.states[state].flags.explicit_set) {
192 char method[5] = { '_', 'P', 'S', '0' + state, '\0' };
195 status = acpi_evaluate_object(adev->handle, method, NULL, NULL);
196 if (ACPI_FAILURE(status))
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.
207 * Callers must ensure that the device is power manageable before using this
210 int acpi_device_set_power(struct acpi_device *device, int state)
213 bool cut_power = false;
215 if (!device || (state < ACPI_STATE_D0) || (state > ACPI_STATE_D3_COLD))
218 /* Make sure this is a valid target state */
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)));
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));
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");
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;
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");
255 * In accordance with the ACPI specification first apply power (via
256 * power resources) and then evalute _PSx.
258 if (device->power.flags.power_resources) {
259 result = acpi_power_transition(device, state);
263 result = acpi_dev_pm_explicit_set(device, state);
268 device->power.state = state;
269 state = ACPI_STATE_D3_COLD;
270 result = acpi_power_transition(device, state);
275 printk(KERN_WARNING PREFIX
276 "Device [%s] failed to transition to %s\n",
278 acpi_power_state_string(state));
280 device->power.state = state;
281 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
282 "Device [%s] transitioned to %s\n",
284 acpi_power_state_string(state)));
289 EXPORT_SYMBOL(acpi_device_set_power);
291 int acpi_bus_set_power(acpi_handle handle, int state)
293 struct acpi_device *device;
296 result = acpi_bus_get_device(handle, &device);
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)));
307 return acpi_device_set_power(device, state);
309 EXPORT_SYMBOL(acpi_bus_set_power);
311 int acpi_bus_init_power(struct acpi_device *device)
319 device->power.state = ACPI_STATE_UNKNOWN;
321 result = acpi_device_get_power(device, &state);
325 if (state < ACPI_STATE_D3_COLD && device->power.flags.power_resources) {
326 result = acpi_power_on_resources(device, state);
330 result = acpi_dev_pm_explicit_set(device, state);
334 device->power.state = state;
338 int acpi_bus_update_power(acpi_handle handle, int *state_p)
340 struct acpi_device *device;
344 result = acpi_bus_get_device(handle, &device);
348 result = acpi_device_get_power(device, &state);
352 result = acpi_device_set_power(device, state);
353 if (!result && state_p)
358 EXPORT_SYMBOL_GPL(acpi_bus_update_power);
360 bool acpi_bus_power_manageable(acpi_handle handle)
362 struct acpi_device *device;
365 result = acpi_bus_get_device(handle, &device);
366 return result ? false : device->flags.power_manageable;
368 EXPORT_SYMBOL(acpi_bus_power_manageable);
370 bool acpi_bus_can_wakeup(acpi_handle handle)
372 struct acpi_device *device;
375 result = acpi_bus_get_device(handle, &device);
376 return result ? false : device->wakeup.flags.valid;
378 EXPORT_SYMBOL(acpi_bus_can_wakeup);
381 * acpi_device_power_state - Get preferred power state of ACPI device.
382 * @dev: Device whose preferred target power state to return.
383 * @adev: ACPI device node corresponding to @dev.
384 * @target_state: System state to match the resultant device state.
385 * @d_max_in: Deepest low-power state to take into consideration.
386 * @d_min_p: Location to store the upper limit of the allowed states range.
387 * Return value: Preferred power state of the device on success, -ENODEV
388 * (if there's no 'struct acpi_device' for @dev) or -EINVAL on failure
390 * Find the lowest power (highest number) ACPI device power state that the
391 * device can be in while the system is in the state represented by
392 * @target_state. If @d_min_p is set, the highest power (lowest number) device
393 * power state that @dev can be in for the given system sleep state is stored
394 * at the location pointed to by it.
396 * Callers must ensure that @dev and @adev are valid pointers and that @adev
397 * actually corresponds to @dev before using this function.
399 int acpi_device_power_state(struct device *dev, struct acpi_device *adev,
400 u32 target_state, int d_max_in, int *d_min_p)
402 char acpi_method[] = "_SxD";
403 unsigned long long d_min, d_max;
406 if (d_max_in < ACPI_STATE_D0 || d_max_in > ACPI_STATE_D3)
409 if (d_max_in > ACPI_STATE_D3_HOT) {
410 enum pm_qos_flags_status stat;
412 stat = dev_pm_qos_flags(dev, PM_QOS_FLAG_NO_POWER_OFF);
413 if (stat == PM_QOS_FLAGS_ALL)
414 d_max_in = ACPI_STATE_D3_HOT;
417 acpi_method[2] = '0' + target_state;
419 * If the sleep state is S0, the lowest limit from ACPI is D3,
420 * but if the device has _S0W, we will use the value from _S0W
421 * as the lowest limit from ACPI. Finally, we will constrain
422 * the lowest limit with the specified one.
424 d_min = ACPI_STATE_D0;
425 d_max = ACPI_STATE_D3;
428 * If present, _SxD methods return the minimum D-state (highest power
429 * state) we can use for the corresponding S-states. Otherwise, the
430 * minimum D-state is D0 (ACPI 3.x).
432 * NOTE: We rely on acpi_evaluate_integer() not clobbering the integer
433 * provided -- that's our fault recovery, we ignore retval.
435 if (target_state > ACPI_STATE_S0) {
436 acpi_evaluate_integer(adev->handle, acpi_method, NULL, &d_min);
437 wakeup = device_may_wakeup(dev) && adev->wakeup.flags.valid
438 && adev->wakeup.sleep_state >= target_state;
439 } else if (dev_pm_qos_flags(dev, PM_QOS_FLAG_REMOTE_WAKEUP) !=
441 wakeup = adev->wakeup.flags.valid;
445 * If _PRW says we can wake up the system from the target sleep state,
446 * the D-state returned by _SxD is sufficient for that (we assume a
447 * wakeup-aware driver if wake is set). Still, if _SxW exists
448 * (ACPI 3.x), it should return the maximum (lowest power) D-state that
449 * can wake the system. _S0W may be valid, too.
454 acpi_method[3] = 'W';
455 status = acpi_evaluate_integer(adev->handle, acpi_method, NULL,
457 if (ACPI_FAILURE(status)) {
458 if (target_state != ACPI_STATE_S0 ||
459 status != AE_NOT_FOUND)
461 } else if (d_max < d_min) {
462 /* Warn the user of the broken DSDT */
463 printk(KERN_WARNING "ACPI: Wrong value from %s\n",
470 if (d_max_in < d_min)
474 /* constrain d_max with specified lowest limit (max number) */
475 if (d_max > d_max_in) {
476 for (d_max = d_max_in; d_max > d_min; d_max--) {
477 if (adev->power.states[d_max].flags.valid)
483 EXPORT_SYMBOL_GPL(acpi_device_power_state);
486 * acpi_pm_device_sleep_state - Get preferred power state of ACPI device.
487 * @dev: Device whose preferred target power state to return.
488 * @d_min_p: Location to store the upper limit of the allowed states range.
489 * @d_max_in: Deepest low-power state to take into consideration.
490 * Return value: Preferred power state of the device on success, -ENODEV
491 * (if there's no 'struct acpi_device' for @dev) or -EINVAL on failure
493 * The caller must ensure that @dev is valid before using this function.
495 int acpi_pm_device_sleep_state(struct device *dev, int *d_min_p, int d_max_in)
497 acpi_handle handle = DEVICE_ACPI_HANDLE(dev);
498 struct acpi_device *adev;
500 if (!handle || ACPI_FAILURE(acpi_bus_get_device(handle, &adev))) {
501 dev_dbg(dev, "ACPI handle without context in %s!\n", __func__);
505 return acpi_device_power_state(dev, adev, acpi_target_system_state(),
508 EXPORT_SYMBOL(acpi_pm_device_sleep_state);
510 #ifdef CONFIG_PM_RUNTIME
512 * acpi_wakeup_device - Wakeup notification handler for ACPI devices.
513 * @handle: ACPI handle of the device the notification is for.
514 * @event: Type of the signaled event.
515 * @context: Device corresponding to @handle.
517 static void acpi_wakeup_device(acpi_handle handle, u32 event, void *context)
519 struct device *dev = context;
521 if (event == ACPI_NOTIFY_DEVICE_WAKE && dev) {
522 pm_wakeup_event(dev, 0);
523 pm_runtime_resume(dev);
528 * __acpi_device_run_wake - Enable/disable runtime remote wakeup for device.
529 * @adev: ACPI device to enable/disable the remote wakeup for.
530 * @enable: Whether to enable or disable the wakeup functionality.
532 * Enable/disable the GPE associated with @adev so that it can generate
533 * wakeup signals for the device in response to external (remote) events and
534 * enable/disable device wakeup power.
536 * Callers must ensure that @adev is a valid ACPI device node before executing
539 int __acpi_device_run_wake(struct acpi_device *adev, bool enable)
541 struct acpi_device_wakeup *wakeup = &adev->wakeup;
547 error = acpi_enable_wakeup_device_power(adev, ACPI_STATE_S0);
551 res = acpi_enable_gpe(wakeup->gpe_device, wakeup->gpe_number);
552 if (ACPI_FAILURE(res)) {
553 acpi_disable_wakeup_device_power(adev);
557 acpi_disable_gpe(wakeup->gpe_device, wakeup->gpe_number);
558 acpi_disable_wakeup_device_power(adev);
564 * acpi_pm_device_run_wake - Enable/disable remote wakeup for given device.
565 * @dev: Device to enable/disable the platform to wake up.
566 * @enable: Whether to enable or disable the wakeup functionality.
568 int acpi_pm_device_run_wake(struct device *phys_dev, bool enable)
570 struct acpi_device *adev;
573 if (!device_run_wake(phys_dev))
576 handle = DEVICE_ACPI_HANDLE(phys_dev);
577 if (!handle || ACPI_FAILURE(acpi_bus_get_device(handle, &adev))) {
578 dev_dbg(phys_dev, "ACPI handle without context in %s!\n",
583 return __acpi_device_run_wake(adev, enable);
585 EXPORT_SYMBOL(acpi_pm_device_run_wake);
587 static inline void acpi_wakeup_device(acpi_handle handle, u32 event,
589 #endif /* CONFIG_PM_RUNTIME */
591 #ifdef CONFIG_PM_SLEEP
593 * __acpi_device_sleep_wake - Enable or disable device to wake up the system.
594 * @dev: Device to enable/desible to wake up the system.
595 * @target_state: System state the device is supposed to wake up from.
596 * @enable: Whether to enable or disable @dev to wake up the system.
598 int __acpi_device_sleep_wake(struct acpi_device *adev, u32 target_state,
602 acpi_enable_wakeup_device_power(adev, target_state) :
603 acpi_disable_wakeup_device_power(adev);
607 * acpi_pm_device_sleep_wake - Enable or disable device to wake up the system.
608 * @dev: Device to enable/desible to wake up the system from sleep states.
609 * @enable: Whether to enable or disable @dev to wake up the system.
611 int acpi_pm_device_sleep_wake(struct device *dev, bool enable)
614 struct acpi_device *adev;
617 if (!device_can_wakeup(dev))
620 handle = DEVICE_ACPI_HANDLE(dev);
621 if (!handle || ACPI_FAILURE(acpi_bus_get_device(handle, &adev))) {
622 dev_dbg(dev, "ACPI handle without context in %s!\n", __func__);
626 error = __acpi_device_sleep_wake(adev, acpi_target_system_state(),
629 dev_info(dev, "System wakeup %s by ACPI\n",
630 enable ? "enabled" : "disabled");
634 #endif /* CONFIG_PM_SLEEP */
637 * acpi_dev_pm_get_node - Get ACPI device node for the given physical device.
638 * @dev: Device to get the ACPI node for.
640 struct acpi_device *acpi_dev_pm_get_node(struct device *dev)
642 acpi_handle handle = DEVICE_ACPI_HANDLE(dev);
643 struct acpi_device *adev;
645 return handle && !acpi_bus_get_device(handle, &adev) ? adev : NULL;
649 * acpi_dev_pm_low_power - Put ACPI device into a low-power state.
650 * @dev: Device to put into a low-power state.
651 * @adev: ACPI device node corresponding to @dev.
652 * @system_state: System state to choose the device state for.
654 static int acpi_dev_pm_low_power(struct device *dev, struct acpi_device *adev,
659 if (!acpi_device_power_manageable(adev))
662 power_state = acpi_device_power_state(dev, adev, system_state,
663 ACPI_STATE_D3, NULL);
664 if (power_state < ACPI_STATE_D0 || power_state > ACPI_STATE_D3)
667 return acpi_device_set_power(adev, power_state);
671 * acpi_dev_pm_full_power - Put ACPI device into the full-power state.
672 * @adev: ACPI device node to put into the full-power state.
674 static int acpi_dev_pm_full_power(struct acpi_device *adev)
676 return acpi_device_power_manageable(adev) ?
677 acpi_device_set_power(adev, ACPI_STATE_D0) : 0;
680 #ifdef CONFIG_PM_RUNTIME
682 * acpi_dev_runtime_suspend - Put device into a low-power state using ACPI.
683 * @dev: Device to put into a low-power state.
685 * Put the given device into a runtime low-power state using the standard ACPI
686 * mechanism. Set up remote wakeup if desired, choose the state to put the
687 * device into (this checks if remote wakeup is expected to work too), and set
688 * the power state of the device.
690 int acpi_dev_runtime_suspend(struct device *dev)
692 struct acpi_device *adev = acpi_dev_pm_get_node(dev);
699 remote_wakeup = dev_pm_qos_flags(dev, PM_QOS_FLAG_REMOTE_WAKEUP) >
701 error = __acpi_device_run_wake(adev, remote_wakeup);
702 if (remote_wakeup && error)
705 error = acpi_dev_pm_low_power(dev, adev, ACPI_STATE_S0);
707 __acpi_device_run_wake(adev, false);
711 EXPORT_SYMBOL_GPL(acpi_dev_runtime_suspend);
714 * acpi_dev_runtime_resume - Put device into the full-power state using ACPI.
715 * @dev: Device to put into the full-power state.
717 * Put the given device into the full-power state using the standard ACPI
718 * mechanism at run time. Set the power state of the device to ACPI D0 and
719 * disable remote wakeup.
721 int acpi_dev_runtime_resume(struct device *dev)
723 struct acpi_device *adev = acpi_dev_pm_get_node(dev);
729 error = acpi_dev_pm_full_power(adev);
730 __acpi_device_run_wake(adev, false);
733 EXPORT_SYMBOL_GPL(acpi_dev_runtime_resume);
736 * acpi_subsys_runtime_suspend - Suspend device using ACPI.
737 * @dev: Device to suspend.
739 * Carry out the generic runtime suspend procedure for @dev and use ACPI to put
740 * it into a runtime low-power state.
742 int acpi_subsys_runtime_suspend(struct device *dev)
744 int ret = pm_generic_runtime_suspend(dev);
745 return ret ? ret : acpi_dev_runtime_suspend(dev);
747 EXPORT_SYMBOL_GPL(acpi_subsys_runtime_suspend);
750 * acpi_subsys_runtime_resume - Resume device using ACPI.
751 * @dev: Device to Resume.
753 * Use ACPI to put the given device into the full-power state and carry out the
754 * generic runtime resume procedure for it.
756 int acpi_subsys_runtime_resume(struct device *dev)
758 int ret = acpi_dev_runtime_resume(dev);
759 return ret ? ret : pm_generic_runtime_resume(dev);
761 EXPORT_SYMBOL_GPL(acpi_subsys_runtime_resume);
762 #endif /* CONFIG_PM_RUNTIME */
764 #ifdef CONFIG_PM_SLEEP
766 * acpi_dev_suspend_late - Put device into a low-power state using ACPI.
767 * @dev: Device to put into a low-power state.
769 * Put the given device into a low-power state during system transition to a
770 * sleep state using the standard ACPI mechanism. Set up system wakeup if
771 * desired, choose the state to put the device into (this checks if system
772 * wakeup is expected to work too), and set the power state of the device.
774 int acpi_dev_suspend_late(struct device *dev)
776 struct acpi_device *adev = acpi_dev_pm_get_node(dev);
784 target_state = acpi_target_system_state();
785 wakeup = device_may_wakeup(dev);
786 error = __acpi_device_sleep_wake(adev, target_state, wakeup);
790 error = acpi_dev_pm_low_power(dev, adev, target_state);
792 __acpi_device_sleep_wake(adev, ACPI_STATE_UNKNOWN, false);
796 EXPORT_SYMBOL_GPL(acpi_dev_suspend_late);
799 * acpi_dev_resume_early - Put device into the full-power state using ACPI.
800 * @dev: Device to put into the full-power state.
802 * Put the given device into the full-power state using the standard ACPI
803 * mechanism during system transition to the working state. Set the power
804 * state of the device to ACPI D0 and disable remote wakeup.
806 int acpi_dev_resume_early(struct device *dev)
808 struct acpi_device *adev = acpi_dev_pm_get_node(dev);
814 error = acpi_dev_pm_full_power(adev);
815 __acpi_device_sleep_wake(adev, ACPI_STATE_UNKNOWN, false);
818 EXPORT_SYMBOL_GPL(acpi_dev_resume_early);
821 * acpi_subsys_prepare - Prepare device for system transition to a sleep state.
822 * @dev: Device to prepare.
824 int acpi_subsys_prepare(struct device *dev)
827 * Follow PCI and resume devices suspended at run time before running
828 * their system suspend callbacks.
830 pm_runtime_resume(dev);
831 return pm_generic_prepare(dev);
833 EXPORT_SYMBOL_GPL(acpi_subsys_prepare);
836 * acpi_subsys_suspend_late - Suspend device using ACPI.
837 * @dev: Device to suspend.
839 * Carry out the generic late suspend procedure for @dev and use ACPI to put
840 * it into a low-power state during system transition into a sleep state.
842 int acpi_subsys_suspend_late(struct device *dev)
844 int ret = pm_generic_suspend_late(dev);
845 return ret ? ret : acpi_dev_suspend_late(dev);
847 EXPORT_SYMBOL_GPL(acpi_subsys_suspend_late);
850 * acpi_subsys_resume_early - Resume device using ACPI.
851 * @dev: Device to Resume.
853 * Use ACPI to put the given device into the full-power state and carry out the
854 * generic early resume procedure for it during system transition into the
857 int acpi_subsys_resume_early(struct device *dev)
859 int ret = acpi_dev_resume_early(dev);
860 return ret ? ret : pm_generic_resume_early(dev);
862 EXPORT_SYMBOL_GPL(acpi_subsys_resume_early);
863 #endif /* CONFIG_PM_SLEEP */
865 static struct dev_pm_domain acpi_general_pm_domain = {
867 #ifdef CONFIG_PM_RUNTIME
868 .runtime_suspend = acpi_subsys_runtime_suspend,
869 .runtime_resume = acpi_subsys_runtime_resume,
870 .runtime_idle = pm_generic_runtime_idle,
872 #ifdef CONFIG_PM_SLEEP
873 .prepare = acpi_subsys_prepare,
874 .suspend_late = acpi_subsys_suspend_late,
875 .resume_early = acpi_subsys_resume_early,
876 .poweroff_late = acpi_subsys_suspend_late,
877 .restore_early = acpi_subsys_resume_early,
883 * acpi_dev_pm_attach - Prepare device for ACPI power management.
884 * @dev: Device to prepare.
885 * @power_on: Whether or not to power on the device.
887 * If @dev has a valid ACPI handle that has a valid struct acpi_device object
888 * attached to it, install a wakeup notification handler for the device and
889 * add it to the general ACPI PM domain. If @power_on is set, the device will
890 * be put into the ACPI D0 state before the function returns.
892 * This assumes that the @dev's bus type uses generic power management callbacks
893 * (or doesn't use any power management callbacks at all).
895 * Callers must ensure proper synchronization of this function with power
896 * management callbacks.
898 int acpi_dev_pm_attach(struct device *dev, bool power_on)
900 struct acpi_device *adev = acpi_dev_pm_get_node(dev);
908 acpi_add_pm_notifier(adev, acpi_wakeup_device, dev);
909 dev->pm_domain = &acpi_general_pm_domain;
911 acpi_dev_pm_full_power(adev);
912 __acpi_device_run_wake(adev, false);
916 EXPORT_SYMBOL_GPL(acpi_dev_pm_attach);
919 * acpi_dev_pm_detach - Remove ACPI power management from the device.
920 * @dev: Device to take care of.
921 * @power_off: Whether or not to try to remove power from the device.
923 * Remove the device from the general ACPI PM domain and remove its wakeup
924 * notifier. If @power_off is set, additionally remove power from the device if
927 * Callers must ensure proper synchronization of this function with power
928 * management callbacks.
930 void acpi_dev_pm_detach(struct device *dev, bool power_off)
932 struct acpi_device *adev = acpi_dev_pm_get_node(dev);
934 if (adev && dev->pm_domain == &acpi_general_pm_domain) {
935 dev->pm_domain = NULL;
936 acpi_remove_pm_notifier(adev, acpi_wakeup_device);
939 * If the device's PM QoS resume latency limit or flags
940 * have been exposed to user space, they have to be
941 * hidden at this point, so that they don't affect the
942 * choice of the low-power state to put the device into.
944 dev_pm_qos_hide_latency_limit(dev);
945 dev_pm_qos_hide_flags(dev);
946 __acpi_device_run_wake(adev, false);
947 acpi_dev_pm_low_power(dev, adev, ACPI_STATE_S0);
951 EXPORT_SYMBOL_GPL(acpi_dev_pm_detach);
954 * acpi_dev_pm_add_dependent - Add physical device depending for PM.
955 * @handle: Handle of ACPI device node.
956 * @depdev: Device depending on that node for PM.
958 void acpi_dev_pm_add_dependent(acpi_handle handle, struct device *depdev)
960 struct acpi_device_physical_node *dep;
961 struct acpi_device *adev;
963 if (!depdev || acpi_bus_get_device(handle, &adev))
966 mutex_lock(&adev->physical_node_lock);
968 list_for_each_entry(dep, &adev->power_dependent, node)
969 if (dep->dev == depdev)
972 dep = kzalloc(sizeof(*dep), GFP_KERNEL);
975 list_add_tail(&dep->node, &adev->power_dependent);
979 mutex_unlock(&adev->physical_node_lock);
981 EXPORT_SYMBOL_GPL(acpi_dev_pm_add_dependent);
984 * acpi_dev_pm_remove_dependent - Remove physical device depending for PM.
985 * @handle: Handle of ACPI device node.
986 * @depdev: Device depending on that node for PM.
988 void acpi_dev_pm_remove_dependent(acpi_handle handle, struct device *depdev)
990 struct acpi_device_physical_node *dep;
991 struct acpi_device *adev;
993 if (!depdev || acpi_bus_get_device(handle, &adev))
996 mutex_lock(&adev->physical_node_lock);
998 list_for_each_entry(dep, &adev->power_dependent, node)
999 if (dep->dev == depdev) {
1000 list_del(&dep->node);
1005 mutex_unlock(&adev->physical_node_lock);
1007 EXPORT_SYMBOL_GPL(acpi_dev_pm_remove_dependent);