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");
41 * acpi_power_state_string - String representation of ACPI device power state.
42 * @state: ACPI device power state to return the string representation of.
44 const char *acpi_power_state_string(int state)
53 case ACPI_STATE_D3_HOT:
55 case ACPI_STATE_D3_COLD:
63 * acpi_device_get_power - Get power state of an ACPI device.
64 * @device: Device to get the power state of.
65 * @state: Place to store the power state of the device.
67 * This function does not update the device's power.state field, but it may
68 * update its parent's power.state field (when the parent's power state is
69 * unknown and the device's power state turns out to be D0).
71 int acpi_device_get_power(struct acpi_device *device, int *state)
73 int result = ACPI_STATE_UNKNOWN;
75 if (!device || !state)
78 if (!device->flags.power_manageable) {
79 /* TBD: Non-recursive algorithm for walking up hierarchy. */
80 *state = device->parent ?
81 device->parent->power.state : ACPI_STATE_D0;
86 * Get the device's power state from power resources settings and _PSC,
89 if (device->power.flags.power_resources) {
90 int error = acpi_power_get_inferred_state(device, &result);
94 if (device->power.flags.explicit_get) {
95 acpi_handle handle = device->handle;
96 unsigned long long psc;
99 status = acpi_evaluate_integer(handle, "_PSC", NULL, &psc);
100 if (ACPI_FAILURE(status))
104 * The power resources settings may indicate a power state
105 * shallower than the actual power state of the device.
107 * Moreover, on systems predating ACPI 4.0, if the device
108 * doesn't depend on any power resources and _PSC returns 3,
109 * that means "power off". We need to maintain compatibility
110 * with those systems.
112 if (psc > result && psc < ACPI_STATE_D3_COLD)
114 else if (result == ACPI_STATE_UNKNOWN)
115 result = psc > ACPI_STATE_D2 ? ACPI_STATE_D3_COLD : psc;
119 * If we were unsure about the device parent's power state up to this
120 * point, the fact that the device is in D0 implies that the parent has
123 if (device->parent && device->parent->power.state == ACPI_STATE_UNKNOWN
124 && result == ACPI_STATE_D0)
125 device->parent->power.state = ACPI_STATE_D0;
130 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] power state is %s\n",
131 device->pnp.bus_id, acpi_power_state_string(*state)));
136 static int acpi_dev_pm_explicit_set(struct acpi_device *adev, int state)
138 if (adev->power.states[state].flags.explicit_set) {
139 char method[5] = { '_', 'P', 'S', '0' + state, '\0' };
142 status = acpi_evaluate_object(adev->handle, method, NULL, NULL);
143 if (ACPI_FAILURE(status))
150 * acpi_device_set_power - Set power state of an ACPI device.
151 * @device: Device to set the power state of.
152 * @state: New power state to set.
154 * Callers must ensure that the device is power manageable before using this
157 int acpi_device_set_power(struct acpi_device *device, int state)
160 bool cut_power = false;
162 if (!device || (state < ACPI_STATE_D0) || (state > ACPI_STATE_D3_COLD))
165 /* Make sure this is a valid target state */
167 if (state == device->power.state) {
168 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device is already at %s\n",
169 acpi_power_state_string(state)));
173 if (!device->power.states[state].flags.valid) {
174 printk(KERN_WARNING PREFIX "Device does not support %s\n",
175 acpi_power_state_string(state));
178 if (device->parent && (state < device->parent->power.state)) {
179 printk(KERN_WARNING PREFIX
180 "Cannot set device to a higher-powered"
181 " state than parent\n");
185 /* For D3cold we should first transition into D3hot. */
186 if (state == ACPI_STATE_D3_COLD
187 && device->power.states[ACPI_STATE_D3_COLD].flags.os_accessible) {
188 state = ACPI_STATE_D3_HOT;
192 if (state < device->power.state && state != ACPI_STATE_D0
193 && device->power.state >= ACPI_STATE_D3_HOT) {
194 printk(KERN_WARNING PREFIX
195 "Cannot transition to non-D0 state from D3\n");
202 * In accordance with the ACPI specification first apply power (via
203 * power resources) and then evalute _PSx.
205 if (device->power.flags.power_resources) {
206 result = acpi_power_transition(device, state);
210 result = acpi_dev_pm_explicit_set(device, state);
215 device->power.state = state;
216 state = ACPI_STATE_D3_COLD;
217 result = acpi_power_transition(device, state);
222 printk(KERN_WARNING PREFIX
223 "Device [%s] failed to transition to %s\n",
225 acpi_power_state_string(state));
227 device->power.state = state;
228 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
229 "Device [%s] transitioned to %s\n",
231 acpi_power_state_string(state)));
236 EXPORT_SYMBOL(acpi_device_set_power);
238 int acpi_bus_set_power(acpi_handle handle, int state)
240 struct acpi_device *device;
243 result = acpi_bus_get_device(handle, &device);
247 if (!device->flags.power_manageable) {
248 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
249 "Device [%s] is not power manageable\n",
250 dev_name(&device->dev)));
254 return acpi_device_set_power(device, state);
256 EXPORT_SYMBOL(acpi_bus_set_power);
258 int acpi_bus_init_power(struct acpi_device *device)
266 device->power.state = ACPI_STATE_UNKNOWN;
268 result = acpi_device_get_power(device, &state);
272 if (state < ACPI_STATE_D3_COLD && device->power.flags.power_resources) {
273 result = acpi_power_on_resources(device, state);
277 result = acpi_dev_pm_explicit_set(device, state);
280 } else if (state == ACPI_STATE_UNKNOWN) {
282 * No power resources and missing _PSC? Cross fingers and make
283 * it D0 in hope that this is what the BIOS put the device into.
284 * [We tried to force D0 here by executing _PS0, but that broke
285 * Toshiba P870-303 in a nasty way.]
287 state = ACPI_STATE_D0;
289 device->power.state = state;
293 int acpi_bus_update_power(acpi_handle handle, int *state_p)
295 struct acpi_device *device;
299 result = acpi_bus_get_device(handle, &device);
303 result = acpi_device_get_power(device, &state);
307 if (state == ACPI_STATE_UNKNOWN)
308 state = ACPI_STATE_D0;
310 result = acpi_device_set_power(device, state);
311 if (!result && state_p)
316 EXPORT_SYMBOL_GPL(acpi_bus_update_power);
318 bool acpi_bus_power_manageable(acpi_handle handle)
320 struct acpi_device *device;
323 result = acpi_bus_get_device(handle, &device);
324 return result ? false : device->flags.power_manageable;
326 EXPORT_SYMBOL(acpi_bus_power_manageable);
329 static DEFINE_MUTEX(acpi_pm_notifier_lock);
332 * acpi_add_pm_notifier - Register PM notifier for given ACPI device.
333 * @adev: ACPI device to add the notifier for.
334 * @context: Context information to pass to the notifier routine.
336 * NOTE: @adev need not be a run-wake or wakeup device to be a valid source of
337 * PM wakeup events. For example, wakeup events may be generated for bridges
338 * if one of the devices below the bridge is signaling wakeup, even if the
339 * bridge itself doesn't have a wakeup GPE associated with it.
341 acpi_status acpi_add_pm_notifier(struct acpi_device *adev,
342 acpi_notify_handler handler, void *context)
344 acpi_status status = AE_ALREADY_EXISTS;
346 mutex_lock(&acpi_pm_notifier_lock);
348 if (adev->wakeup.flags.notifier_present)
351 status = acpi_install_notify_handler(adev->handle,
354 if (ACPI_FAILURE(status))
357 adev->wakeup.flags.notifier_present = true;
360 mutex_unlock(&acpi_pm_notifier_lock);
365 * acpi_remove_pm_notifier - Unregister PM notifier from given ACPI device.
366 * @adev: ACPI device to remove the notifier from.
368 acpi_status acpi_remove_pm_notifier(struct acpi_device *adev,
369 acpi_notify_handler handler)
371 acpi_status status = AE_BAD_PARAMETER;
373 mutex_lock(&acpi_pm_notifier_lock);
375 if (!adev->wakeup.flags.notifier_present)
378 status = acpi_remove_notify_handler(adev->handle,
381 if (ACPI_FAILURE(status))
384 adev->wakeup.flags.notifier_present = false;
387 mutex_unlock(&acpi_pm_notifier_lock);
391 bool acpi_bus_can_wakeup(acpi_handle handle)
393 struct acpi_device *device;
396 result = acpi_bus_get_device(handle, &device);
397 return result ? false : device->wakeup.flags.valid;
399 EXPORT_SYMBOL(acpi_bus_can_wakeup);
402 * acpi_device_power_state - Get preferred power state of ACPI device.
403 * @dev: Device whose preferred target power state to return.
404 * @adev: ACPI device node corresponding to @dev.
405 * @target_state: System state to match the resultant device state.
406 * @d_max_in: Deepest low-power state to take into consideration.
407 * @d_min_p: Location to store the upper limit of the allowed states range.
408 * Return value: Preferred power state of the device on success, -ENODEV
409 * (if there's no 'struct acpi_device' for @dev) or -EINVAL on failure
411 * Find the lowest power (highest number) ACPI device power state that the
412 * device can be in while the system is in the state represented by
413 * @target_state. If @d_min_p is set, the highest power (lowest number) device
414 * power state that @dev can be in for the given system sleep state is stored
415 * at the location pointed to by it.
417 * Callers must ensure that @dev and @adev are valid pointers and that @adev
418 * actually corresponds to @dev before using this function.
420 int acpi_device_power_state(struct device *dev, struct acpi_device *adev,
421 u32 target_state, int d_max_in, int *d_min_p)
423 char acpi_method[] = "_SxD";
424 unsigned long long d_min, d_max;
427 if (d_max_in < ACPI_STATE_D0 || d_max_in > ACPI_STATE_D3)
430 if (d_max_in > ACPI_STATE_D3_HOT) {
431 enum pm_qos_flags_status stat;
433 stat = dev_pm_qos_flags(dev, PM_QOS_FLAG_NO_POWER_OFF);
434 if (stat == PM_QOS_FLAGS_ALL)
435 d_max_in = ACPI_STATE_D3_HOT;
438 acpi_method[2] = '0' + target_state;
440 * If the sleep state is S0, the lowest limit from ACPI is D3,
441 * but if the device has _S0W, we will use the value from _S0W
442 * as the lowest limit from ACPI. Finally, we will constrain
443 * the lowest limit with the specified one.
445 d_min = ACPI_STATE_D0;
446 d_max = ACPI_STATE_D3;
449 * If present, _SxD methods return the minimum D-state (highest power
450 * state) we can use for the corresponding S-states. Otherwise, the
451 * minimum D-state is D0 (ACPI 3.x).
453 * NOTE: We rely on acpi_evaluate_integer() not clobbering the integer
454 * provided -- that's our fault recovery, we ignore retval.
456 if (target_state > ACPI_STATE_S0) {
457 acpi_evaluate_integer(adev->handle, acpi_method, NULL, &d_min);
458 wakeup = device_may_wakeup(dev) && adev->wakeup.flags.valid
459 && adev->wakeup.sleep_state >= target_state;
460 } else if (dev_pm_qos_flags(dev, PM_QOS_FLAG_REMOTE_WAKEUP) !=
462 wakeup = adev->wakeup.flags.valid;
466 * If _PRW says we can wake up the system from the target sleep state,
467 * the D-state returned by _SxD is sufficient for that (we assume a
468 * wakeup-aware driver if wake is set). Still, if _SxW exists
469 * (ACPI 3.x), it should return the maximum (lowest power) D-state that
470 * can wake the system. _S0W may be valid, too.
475 acpi_method[3] = 'W';
476 status = acpi_evaluate_integer(adev->handle, acpi_method, NULL,
478 if (ACPI_FAILURE(status)) {
479 if (target_state != ACPI_STATE_S0 ||
480 status != AE_NOT_FOUND)
482 } else if (d_max < d_min) {
483 /* Warn the user of the broken DSDT */
484 printk(KERN_WARNING "ACPI: Wrong value from %s\n",
491 if (d_max_in < d_min)
495 /* constrain d_max with specified lowest limit (max number) */
496 if (d_max > d_max_in) {
497 for (d_max = d_max_in; d_max > d_min; d_max--) {
498 if (adev->power.states[d_max].flags.valid)
504 EXPORT_SYMBOL_GPL(acpi_device_power_state);
507 * acpi_pm_device_sleep_state - Get preferred power state of ACPI device.
508 * @dev: Device whose preferred target power state to return.
509 * @d_min_p: Location to store the upper limit of the allowed states range.
510 * @d_max_in: Deepest low-power state to take into consideration.
511 * Return value: Preferred power state of the device on success, -ENODEV
512 * (if there's no 'struct acpi_device' for @dev) or -EINVAL on failure
514 * The caller must ensure that @dev is valid before using this function.
516 int acpi_pm_device_sleep_state(struct device *dev, int *d_min_p, int d_max_in)
518 acpi_handle handle = DEVICE_ACPI_HANDLE(dev);
519 struct acpi_device *adev;
521 if (!handle || acpi_bus_get_device(handle, &adev)) {
522 dev_dbg(dev, "ACPI handle without context in %s!\n", __func__);
526 return acpi_device_power_state(dev, adev, acpi_target_system_state(),
529 EXPORT_SYMBOL(acpi_pm_device_sleep_state);
531 #ifdef CONFIG_PM_RUNTIME
533 * acpi_wakeup_device - Wakeup notification handler for ACPI devices.
534 * @handle: ACPI handle of the device the notification is for.
535 * @event: Type of the signaled event.
536 * @context: Device corresponding to @handle.
538 static void acpi_wakeup_device(acpi_handle handle, u32 event, void *context)
540 struct device *dev = context;
542 if (event == ACPI_NOTIFY_DEVICE_WAKE && dev) {
543 pm_wakeup_event(dev, 0);
544 pm_runtime_resume(dev);
549 * __acpi_device_run_wake - Enable/disable runtime remote wakeup for device.
550 * @adev: ACPI device to enable/disable the remote wakeup for.
551 * @enable: Whether to enable or disable the wakeup functionality.
553 * Enable/disable the GPE associated with @adev so that it can generate
554 * wakeup signals for the device in response to external (remote) events and
555 * enable/disable device wakeup power.
557 * Callers must ensure that @adev is a valid ACPI device node before executing
560 int __acpi_device_run_wake(struct acpi_device *adev, bool enable)
562 struct acpi_device_wakeup *wakeup = &adev->wakeup;
568 error = acpi_enable_wakeup_device_power(adev, ACPI_STATE_S0);
572 res = acpi_enable_gpe(wakeup->gpe_device, wakeup->gpe_number);
573 if (ACPI_FAILURE(res)) {
574 acpi_disable_wakeup_device_power(adev);
578 acpi_disable_gpe(wakeup->gpe_device, wakeup->gpe_number);
579 acpi_disable_wakeup_device_power(adev);
585 * acpi_pm_device_run_wake - Enable/disable remote wakeup for given device.
586 * @dev: Device to enable/disable the platform to wake up.
587 * @enable: Whether to enable or disable the wakeup functionality.
589 int acpi_pm_device_run_wake(struct device *phys_dev, bool enable)
591 struct acpi_device *adev;
594 if (!device_run_wake(phys_dev))
597 handle = DEVICE_ACPI_HANDLE(phys_dev);
598 if (!handle || acpi_bus_get_device(handle, &adev)) {
599 dev_dbg(phys_dev, "ACPI handle without context in %s!\n",
604 return __acpi_device_run_wake(adev, enable);
606 EXPORT_SYMBOL(acpi_pm_device_run_wake);
608 static inline void acpi_wakeup_device(acpi_handle handle, u32 event,
610 #endif /* CONFIG_PM_RUNTIME */
612 #ifdef CONFIG_PM_SLEEP
614 * __acpi_device_sleep_wake - Enable or disable device to wake up the system.
615 * @dev: Device to enable/desible to wake up the system.
616 * @target_state: System state the device is supposed to wake up from.
617 * @enable: Whether to enable or disable @dev to wake up the system.
619 int __acpi_device_sleep_wake(struct acpi_device *adev, u32 target_state,
623 acpi_enable_wakeup_device_power(adev, target_state) :
624 acpi_disable_wakeup_device_power(adev);
628 * acpi_pm_device_sleep_wake - Enable or disable device to wake up the system.
629 * @dev: Device to enable/desible to wake up the system from sleep states.
630 * @enable: Whether to enable or disable @dev to wake up the system.
632 int acpi_pm_device_sleep_wake(struct device *dev, bool enable)
635 struct acpi_device *adev;
638 if (!device_can_wakeup(dev))
641 handle = DEVICE_ACPI_HANDLE(dev);
642 if (!handle || acpi_bus_get_device(handle, &adev)) {
643 dev_dbg(dev, "ACPI handle without context in %s!\n", __func__);
647 error = __acpi_device_sleep_wake(adev, acpi_target_system_state(),
650 dev_info(dev, "System wakeup %s by ACPI\n",
651 enable ? "enabled" : "disabled");
655 #endif /* CONFIG_PM_SLEEP */
658 * acpi_dev_pm_get_node - Get ACPI device node for the given physical device.
659 * @dev: Device to get the ACPI node for.
661 struct acpi_device *acpi_dev_pm_get_node(struct device *dev)
663 acpi_handle handle = DEVICE_ACPI_HANDLE(dev);
664 struct acpi_device *adev;
666 return handle && !acpi_bus_get_device(handle, &adev) ? adev : NULL;
670 * acpi_dev_pm_low_power - Put ACPI device into a low-power state.
671 * @dev: Device to put into a low-power state.
672 * @adev: ACPI device node corresponding to @dev.
673 * @system_state: System state to choose the device state for.
675 static int acpi_dev_pm_low_power(struct device *dev, struct acpi_device *adev,
680 if (!acpi_device_power_manageable(adev))
683 power_state = acpi_device_power_state(dev, adev, system_state,
684 ACPI_STATE_D3, NULL);
685 if (power_state < ACPI_STATE_D0 || power_state > ACPI_STATE_D3)
688 return acpi_device_set_power(adev, power_state);
692 * acpi_dev_pm_full_power - Put ACPI device into the full-power state.
693 * @adev: ACPI device node to put into the full-power state.
695 static int acpi_dev_pm_full_power(struct acpi_device *adev)
697 return acpi_device_power_manageable(adev) ?
698 acpi_device_set_power(adev, ACPI_STATE_D0) : 0;
701 #ifdef CONFIG_PM_RUNTIME
703 * acpi_dev_runtime_suspend - Put device into a low-power state using ACPI.
704 * @dev: Device to put into a low-power state.
706 * Put the given device into a runtime low-power state using the standard ACPI
707 * mechanism. Set up remote wakeup if desired, choose the state to put the
708 * device into (this checks if remote wakeup is expected to work too), and set
709 * the power state of the device.
711 int acpi_dev_runtime_suspend(struct device *dev)
713 struct acpi_device *adev = acpi_dev_pm_get_node(dev);
720 remote_wakeup = dev_pm_qos_flags(dev, PM_QOS_FLAG_REMOTE_WAKEUP) >
722 error = __acpi_device_run_wake(adev, remote_wakeup);
723 if (remote_wakeup && error)
726 error = acpi_dev_pm_low_power(dev, adev, ACPI_STATE_S0);
728 __acpi_device_run_wake(adev, false);
732 EXPORT_SYMBOL_GPL(acpi_dev_runtime_suspend);
735 * acpi_dev_runtime_resume - Put device into the full-power state using ACPI.
736 * @dev: Device to put into the full-power state.
738 * Put the given device into the full-power state using the standard ACPI
739 * mechanism at run time. Set the power state of the device to ACPI D0 and
740 * disable remote wakeup.
742 int acpi_dev_runtime_resume(struct device *dev)
744 struct acpi_device *adev = acpi_dev_pm_get_node(dev);
750 error = acpi_dev_pm_full_power(adev);
751 __acpi_device_run_wake(adev, false);
754 EXPORT_SYMBOL_GPL(acpi_dev_runtime_resume);
757 * acpi_subsys_runtime_suspend - Suspend device using ACPI.
758 * @dev: Device to suspend.
760 * Carry out the generic runtime suspend procedure for @dev and use ACPI to put
761 * it into a runtime low-power state.
763 int acpi_subsys_runtime_suspend(struct device *dev)
765 int ret = pm_generic_runtime_suspend(dev);
766 return ret ? ret : acpi_dev_runtime_suspend(dev);
768 EXPORT_SYMBOL_GPL(acpi_subsys_runtime_suspend);
771 * acpi_subsys_runtime_resume - Resume device using ACPI.
772 * @dev: Device to Resume.
774 * Use ACPI to put the given device into the full-power state and carry out the
775 * generic runtime resume procedure for it.
777 int acpi_subsys_runtime_resume(struct device *dev)
779 int ret = acpi_dev_runtime_resume(dev);
780 return ret ? ret : pm_generic_runtime_resume(dev);
782 EXPORT_SYMBOL_GPL(acpi_subsys_runtime_resume);
783 #endif /* CONFIG_PM_RUNTIME */
785 #ifdef CONFIG_PM_SLEEP
787 * acpi_dev_suspend_late - Put device into a low-power state using ACPI.
788 * @dev: Device to put into a low-power state.
790 * Put the given device into a low-power state during system transition to a
791 * sleep state using the standard ACPI mechanism. Set up system wakeup if
792 * desired, choose the state to put the device into (this checks if system
793 * wakeup is expected to work too), and set the power state of the device.
795 int acpi_dev_suspend_late(struct device *dev)
797 struct acpi_device *adev = acpi_dev_pm_get_node(dev);
805 target_state = acpi_target_system_state();
806 wakeup = device_may_wakeup(dev);
807 error = __acpi_device_sleep_wake(adev, target_state, wakeup);
811 error = acpi_dev_pm_low_power(dev, adev, target_state);
813 __acpi_device_sleep_wake(adev, ACPI_STATE_UNKNOWN, false);
817 EXPORT_SYMBOL_GPL(acpi_dev_suspend_late);
820 * acpi_dev_resume_early - Put device into the full-power state using ACPI.
821 * @dev: Device to put into the full-power state.
823 * Put the given device into the full-power state using the standard ACPI
824 * mechanism during system transition to the working state. Set the power
825 * state of the device to ACPI D0 and disable remote wakeup.
827 int acpi_dev_resume_early(struct device *dev)
829 struct acpi_device *adev = acpi_dev_pm_get_node(dev);
835 error = acpi_dev_pm_full_power(adev);
836 __acpi_device_sleep_wake(adev, ACPI_STATE_UNKNOWN, false);
839 EXPORT_SYMBOL_GPL(acpi_dev_resume_early);
842 * acpi_subsys_prepare - Prepare device for system transition to a sleep state.
843 * @dev: Device to prepare.
845 int acpi_subsys_prepare(struct device *dev)
848 * Follow PCI and resume devices suspended at run time before running
849 * their system suspend callbacks.
851 pm_runtime_resume(dev);
852 return pm_generic_prepare(dev);
854 EXPORT_SYMBOL_GPL(acpi_subsys_prepare);
857 * acpi_subsys_suspend_late - Suspend device using ACPI.
858 * @dev: Device to suspend.
860 * Carry out the generic late suspend procedure for @dev and use ACPI to put
861 * it into a low-power state during system transition into a sleep state.
863 int acpi_subsys_suspend_late(struct device *dev)
865 int ret = pm_generic_suspend_late(dev);
866 return ret ? ret : acpi_dev_suspend_late(dev);
868 EXPORT_SYMBOL_GPL(acpi_subsys_suspend_late);
871 * acpi_subsys_resume_early - Resume device using ACPI.
872 * @dev: Device to Resume.
874 * Use ACPI to put the given device into the full-power state and carry out the
875 * generic early resume procedure for it during system transition into the
878 int acpi_subsys_resume_early(struct device *dev)
880 int ret = acpi_dev_resume_early(dev);
881 return ret ? ret : pm_generic_resume_early(dev);
883 EXPORT_SYMBOL_GPL(acpi_subsys_resume_early);
884 #endif /* CONFIG_PM_SLEEP */
886 static struct dev_pm_domain acpi_general_pm_domain = {
888 #ifdef CONFIG_PM_RUNTIME
889 .runtime_suspend = acpi_subsys_runtime_suspend,
890 .runtime_resume = acpi_subsys_runtime_resume,
891 .runtime_idle = pm_generic_runtime_idle,
893 #ifdef CONFIG_PM_SLEEP
894 .prepare = acpi_subsys_prepare,
895 .suspend_late = acpi_subsys_suspend_late,
896 .resume_early = acpi_subsys_resume_early,
897 .poweroff_late = acpi_subsys_suspend_late,
898 .restore_early = acpi_subsys_resume_early,
904 * acpi_dev_pm_attach - Prepare device for ACPI power management.
905 * @dev: Device to prepare.
906 * @power_on: Whether or not to power on the device.
908 * If @dev has a valid ACPI handle that has a valid struct acpi_device object
909 * attached to it, install a wakeup notification handler for the device and
910 * add it to the general ACPI PM domain. If @power_on is set, the device will
911 * be put into the ACPI D0 state before the function returns.
913 * This assumes that the @dev's bus type uses generic power management callbacks
914 * (or doesn't use any power management callbacks at all).
916 * Callers must ensure proper synchronization of this function with power
917 * management callbacks.
919 int acpi_dev_pm_attach(struct device *dev, bool power_on)
921 struct acpi_device *adev = acpi_dev_pm_get_node(dev);
929 acpi_add_pm_notifier(adev, acpi_wakeup_device, dev);
930 dev->pm_domain = &acpi_general_pm_domain;
932 acpi_dev_pm_full_power(adev);
933 __acpi_device_run_wake(adev, false);
937 EXPORT_SYMBOL_GPL(acpi_dev_pm_attach);
940 * acpi_dev_pm_detach - Remove ACPI power management from the device.
941 * @dev: Device to take care of.
942 * @power_off: Whether or not to try to remove power from the device.
944 * Remove the device from the general ACPI PM domain and remove its wakeup
945 * notifier. If @power_off is set, additionally remove power from the device if
948 * Callers must ensure proper synchronization of this function with power
949 * management callbacks.
951 void acpi_dev_pm_detach(struct device *dev, bool power_off)
953 struct acpi_device *adev = acpi_dev_pm_get_node(dev);
955 if (adev && dev->pm_domain == &acpi_general_pm_domain) {
956 dev->pm_domain = NULL;
957 acpi_remove_pm_notifier(adev, acpi_wakeup_device);
960 * If the device's PM QoS resume latency limit or flags
961 * have been exposed to user space, they have to be
962 * hidden at this point, so that they don't affect the
963 * choice of the low-power state to put the device into.
965 dev_pm_qos_hide_latency_limit(dev);
966 dev_pm_qos_hide_flags(dev);
967 __acpi_device_run_wake(adev, false);
968 acpi_dev_pm_low_power(dev, adev, ACPI_STATE_S0);
972 EXPORT_SYMBOL_GPL(acpi_dev_pm_detach);
975 * acpi_dev_pm_add_dependent - Add physical device depending for PM.
976 * @handle: Handle of ACPI device node.
977 * @depdev: Device depending on that node for PM.
979 void acpi_dev_pm_add_dependent(acpi_handle handle, struct device *depdev)
981 struct acpi_device_physical_node *dep;
982 struct acpi_device *adev;
984 if (!depdev || acpi_bus_get_device(handle, &adev))
987 mutex_lock(&adev->physical_node_lock);
989 list_for_each_entry(dep, &adev->power_dependent, node)
990 if (dep->dev == depdev)
993 dep = kzalloc(sizeof(*dep), GFP_KERNEL);
996 list_add_tail(&dep->node, &adev->power_dependent);
1000 mutex_unlock(&adev->physical_node_lock);
1002 EXPORT_SYMBOL_GPL(acpi_dev_pm_add_dependent);
1005 * acpi_dev_pm_remove_dependent - Remove physical device depending for PM.
1006 * @handle: Handle of ACPI device node.
1007 * @depdev: Device depending on that node for PM.
1009 void acpi_dev_pm_remove_dependent(acpi_handle handle, struct device *depdev)
1011 struct acpi_device_physical_node *dep;
1012 struct acpi_device *adev;
1014 if (!depdev || acpi_bus_get_device(handle, &adev))
1017 mutex_lock(&adev->physical_node_lock);
1019 list_for_each_entry(dep, &adev->power_dependent, node)
1020 if (dep->dev == depdev) {
1021 list_del(&dep->node);
1026 mutex_unlock(&adev->physical_node_lock);
1028 EXPORT_SYMBOL_GPL(acpi_dev_pm_remove_dependent);
1029 #endif /* CONFIG_PM */