1 // SPDX-License-Identifier: GPL-2.0-only
3  * drivers/acpi/device_pm.c - ACPI device power management routines.
27  * acpi_power_state_string - String representation of ACPI device power state.
28  * @state: ACPI device power state to return the string representation of.
53 	status = acpi_evaluate_integer(device->handle, "_PSC", NULL, &psc);  in acpi_dev_pm_explicit_get()
55 		return -ENODEV;  in acpi_dev_pm_explicit_get()
62  * acpi_device_get_power - Get power state of an ACPI device.
63  * @device: Device to get the power state of.
64  * @state: Place to store the power state of the device.
66  * This function does not update the device's power.state field, but it may
67  * update its parent's power.state field (when the parent's power state is
68  * unknown and the device's power state turns out to be D0).
70  * Also, it does not update power resource reference counters to ensure that
71  * the power state returned by it will be persistent and it may return a power
73  * (if that power state depends on any power resources).
81 		return -EINVAL;  in acpi_device_get_power()
83 	if (!device->flags.power_manageable) {  in acpi_device_get_power()
84 		/* TBD: Non-recursive algorithm for walking up hierarchy. */  in acpi_device_get_power()
85 		*state = device->parent ?  in acpi_device_get_power()
86 			device->parent->power.state : ACPI_STATE_D0;  in acpi_device_get_power()
91 	 * Get the device's power state from power resources settings and _PSC,  in acpi_device_get_power()
94 	if (device->power.flags.power_resources) {  in acpi_device_get_power()
99 	if (device->power.flags.explicit_get) {  in acpi_device_get_power()
107 		 * The power resources settings may indicate a power state  in acpi_device_get_power()
108 		 * shallower than the actual power state of the device, because  in acpi_device_get_power()
109 		 * the same power resources may be referenced by other devices.  in acpi_device_get_power()
121 	 * If we were unsure about the device parent's power state up to this  in acpi_device_get_power()
125 	if (!device->power.flags.ignore_parent && device->parent  in acpi_device_get_power()
126 	    && device->parent->power.state == ACPI_STATE_UNKNOWN  in acpi_device_get_power()
128 		device->parent->power.state = ACPI_STATE_D0;  in acpi_device_get_power()
133 	dev_dbg(&device->dev, "Device power state is %s\n",  in acpi_device_get_power()
141 	if (adev->power.states[state].flags.explicit_set) {  in acpi_dev_pm_explicit_set()
145 		status = acpi_evaluate_object(adev->handle, method, NULL, NULL);  in acpi_dev_pm_explicit_set()
147 			return -ENODEV;  in acpi_dev_pm_explicit_set()
153  * acpi_device_set_power - Set power state of an ACPI device.
154  * @device: Device to set the power state of.
155  * @state: New power state to set.
157  * Callers must ensure that the device is power manageable before using this
165 	if (!device || !device->flags.power_manageable  in acpi_device_set_power()
167 		return -EINVAL;  in acpi_device_set_power()
169 	acpi_handle_debug(device->handle, "Power state change: %s -> %s\n",  in acpi_device_set_power()
170 			  acpi_power_state_string(device->power.state),  in acpi_device_set_power()
176 	if (state > ACPI_STATE_D0 && state == device->power.state) {  in acpi_device_set_power()
177 		dev_dbg(&device->dev, "Device already in %s\n",  in acpi_device_set_power()
185 		 * possibly drop references to the power resources in use.  in acpi_device_set_power()
189 		if (!device->power.states[ACPI_STATE_D3_COLD].flags.valid)  in acpi_device_set_power()
191 	} else if (!device->power.states[state].flags.valid) {  in acpi_device_set_power()
192 		dev_warn(&device->dev, "Power state %s not supported\n",  in acpi_device_set_power()
194 		return -ENODEV;  in acpi_device_set_power()
197 	if (!device->power.flags.ignore_parent &&  in acpi_device_set_power()
198 	    device->parent && (state < device->parent->power.state)) {  in acpi_device_set_power()
199 		dev_warn(&device->dev,  in acpi_device_set_power()
200 			 "Cannot transition to power state %s for parent in %s\n",  in acpi_device_set_power()
202 			 acpi_power_state_string(device->parent->power.state));  in acpi_device_set_power()
203 		return -ENODEV;  in acpi_device_set_power()
207 	 * Transition Power  in acpi_device_set_power()
208 	 * ----------------  in acpi_device_set_power()
209 	 * In accordance with ACPI 6, _PSx is executed before manipulating power  in acpi_device_set_power()
211 	 * supposed to be executed after turning the power resources on.  in acpi_device_set_power()
215 		 * According to ACPI 6, devices cannot go from lower-power  in acpi_device_set_power()
216 		 * (deeper) states to higher-power (shallower) states.  in acpi_device_set_power()
218 		if (state < device->power.state) {  in acpi_device_set_power()
219 			dev_warn(&device->dev, "Cannot transition from %s to %s\n",  in acpi_device_set_power()
220 				 acpi_power_state_string(device->power.state),  in acpi_device_set_power()
222 			return -ENODEV;  in acpi_device_set_power()
229 		if (device->power.state < ACPI_STATE_D3_HOT) {  in acpi_device_set_power()
235 		if (device->power.flags.power_resources)  in acpi_device_set_power()
238 		int cur_state = device->power.state;  in acpi_device_set_power()
240 		if (device->power.flags.power_resources) {  in acpi_device_set_power()
250 			if (!device->power.flags.explicit_get)  in acpi_device_set_power()
254 			 * The power state of the device was set to D0 last  in acpi_device_set_power()
256 			 * system-wide transition involving the platform  in acpi_device_set_power()
259 			 * and evaluate _PSC to check the device's current power  in acpi_device_set_power()
261 			 * is successful and it returns a power state different  in acpi_device_set_power()
274 		dev_warn(&device->dev, "Failed to change power state to %s\n",  in acpi_device_set_power()
277 		device->power.state = target_state;  in acpi_device_set_power()
278 		dev_dbg(&device->dev, "Power state changed to %s\n",  in acpi_device_set_power()
305 		return -EINVAL;  in acpi_bus_init_power()
307 	device->power.state = ACPI_STATE_UNKNOWN;  in acpi_bus_init_power()
309 		device->flags.initialized = false;  in acpi_bus_init_power()
310 		return -ENXIO;  in acpi_bus_init_power()
317 	if (state < ACPI_STATE_D3_COLD && device->power.flags.power_resources) {  in acpi_bus_init_power()
318 		/* Reference count the power resources. */  in acpi_bus_init_power()
326 			 * power resources appears to be D0, it still may be  in acpi_bus_init_power()
328 			 * another device using the same power resources may  in acpi_bus_init_power()
338 		 * No power resources and missing _PSC?  Cross fingers and make  in acpi_bus_init_power()
341 		 * Toshiba P870-303 in a nasty way.]  in acpi_bus_init_power()
345 	device->power.state = state;  in acpi_bus_init_power()
350  * acpi_device_fix_up_power - Force device with missing _PSC into D0.
351  * @device: Device object whose power state is to be fixed up.
353  * Devices without power resources and _PSC, but having _PS0 and _PS3 defined,
361 	if (!device->power.flags.power_resources  in acpi_device_fix_up_power()
362 	    && !device->power.flags.explicit_get  in acpi_device_fix_up_power()
363 	    && device->power.state == ACPI_STATE_D0)  in acpi_device_fix_up_power()
375 	if (device->power.state == ACPI_STATE_UNKNOWN) {  in acpi_device_update_power()
378 			*state_p = device->power.state;  in acpi_device_update_power()
393 		if (device->power.flags.power_resources) {  in acpi_device_update_power()
396 			 * to update the power resources' reference counters.  in acpi_device_update_power()
402 		device->power.state = state;  in acpi_device_update_power()
427 	return result ? false : device->flags.power_manageable;  in acpi_bus_power_manageable()
456 	if (adev->wakeup.flags.notifier_present) {  in acpi_pm_notify_handler()
457 		pm_wakeup_ws_event(adev->wakeup.ws, 0, acpi_s2idle_wakeup());  in acpi_pm_notify_handler()
458 		if (adev->wakeup.context.func) {  in acpi_pm_notify_handler()
460 					  adev->wakeup.context.func,  in acpi_pm_notify_handler()
461 					  dev_name(adev->wakeup.context.dev));  in acpi_pm_notify_handler()
462 			adev->wakeup.context.func(&adev->wakeup.context);  in acpi_pm_notify_handler()
472  * acpi_add_pm_notifier - Register PM notify handler for given ACPI device.
477  * NOTE: @adev need not be a run-wake or wakeup device to be a valid source of
492 	if (adev->wakeup.flags.notifier_present)  in acpi_add_pm_notifier()
495 	status = acpi_install_notify_handler(adev->handle, ACPI_SYSTEM_NOTIFY,  in acpi_add_pm_notifier()
501 	adev->wakeup.ws = wakeup_source_register(&adev->dev,  in acpi_add_pm_notifier()
502 						 dev_name(&adev->dev));  in acpi_add_pm_notifier()
503 	adev->wakeup.context.dev = dev;  in acpi_add_pm_notifier()
504 	adev->wakeup.context.func = func;  in acpi_add_pm_notifier()
505 	adev->wakeup.flags.notifier_present = true;  in acpi_add_pm_notifier()
514  * acpi_remove_pm_notifier - Unregister PM notifier from given ACPI device.
523 	if (!adev->wakeup.flags.notifier_present)  in acpi_remove_pm_notifier()
526 	status = acpi_remove_notify_handler(adev->handle,  in acpi_remove_pm_notifier()
533 	adev->wakeup.context.func = NULL;  in acpi_remove_pm_notifier()
534 	adev->wakeup.context.dev = NULL;  in acpi_remove_pm_notifier()
535 	wakeup_source_unregister(adev->wakeup.ws);  in acpi_remove_pm_notifier()
536 	adev->wakeup.flags.notifier_present = false;  in acpi_remove_pm_notifier()
550 	return result ? false : device->wakeup.flags.valid;  in acpi_bus_can_wakeup()
562  * acpi_dev_pm_get_state - Get preferred power state of ACPI device.
563  * @dev: Device whose preferred target power state to return.
566  * @d_min_p: Location to store the highest power state available to the device.
567  * @d_max_p: Location to store the lowest power state available to the device.
569  * Find the lowest power (highest number) and highest power (lowest number) ACPI
570  * device power states that the device can be in while the system is in the
578  * Returns 0 on success or -ENODATA when one of the ACPI methods fails or
586 	acpi_handle handle = adev->handle;  in acpi_dev_pm_get_state()
594 	 * If the system state is S0, the lowest power state the device can be  in acpi_dev_pm_get_state()
597 	 * lowest power state available to the device.  in acpi_dev_pm_get_state()
603 	 * If present, _SxD methods return the minimum D-state (highest power  in acpi_dev_pm_get_state()
604 	 * state) we can use for the corresponding S-states.  Otherwise, the  in acpi_dev_pm_get_state()
605 	 * minimum D-state is D0 (ACPI 3.x).  in acpi_dev_pm_get_state()
616 			return -ENODATA;  in acpi_dev_pm_get_state()
623 		if (!adev->power.states[ret].flags.valid) {  in acpi_dev_pm_get_state()
627 				return -ENODATA;  in acpi_dev_pm_get_state()
634 		wakeup = device_may_wakeup(dev) && adev->wakeup.flags.valid  in acpi_dev_pm_get_state()
635 			&& adev->wakeup.sleep_state >= target_state;  in acpi_dev_pm_get_state()
637 		wakeup = adev->wakeup.flags.valid;  in acpi_dev_pm_get_state()
642 	 * the D-state returned by _SxD is sufficient for that (we assume a  in acpi_dev_pm_get_state()
643 	 * wakeup-aware driver if wake is set).  Still, if _SxW exists  in acpi_dev_pm_get_state()
644 	 * (ACPI 3.x), it should return the maximum (lowest power) D-state that  in acpi_dev_pm_get_state()
652 			 * must not go into any power state deeper than the  in acpi_dev_pm_get_state()
659 			if (!adev->power.states[ret].flags.valid)  in acpi_dev_pm_get_state()
664 			return -ENODATA;  in acpi_dev_pm_get_state()
678  * acpi_pm_device_sleep_state - Get preferred power state of ACPI device.
679  * @dev: Device whose preferred target power state to return.
681  * @d_max_in: Deepest low-power state to take into consideration.
682  * Return value: Preferred power state of the device on success, -ENODEV
683  * if there's no 'struct acpi_device' for @dev, -EINVAL if @d_max_in is
684  * incorrect, or -ENODATA on ACPI method failure.
694 		return -EINVAL;  in acpi_pm_device_sleep_state()
707 		return -ENODEV;  in acpi_pm_device_sleep_state()
716 		return -EINVAL;  in acpi_pm_device_sleep_state()
719 		for (d_max = d_max_in; d_max > d_min; d_max--) {  in acpi_pm_device_sleep_state()
720 			if (adev->power.states[d_max].flags.valid)  in acpi_pm_device_sleep_state()
733  * acpi_pm_notify_work_func - ACPI devices wakeup notification work function.
738 	struct device *dev = context->dev;  in acpi_pm_notify_work_func()
751 	struct acpi_device_wakeup *wakeup = &adev->wakeup;  in __acpi_device_wakeup_enable()
758 	 * If the device wakeup power is already enabled, disable it and enable  in __acpi_device_wakeup_enable()
763 	if (wakeup->enable_count > 0)  in __acpi_device_wakeup_enable()
768 		if (wakeup->enable_count > 0) {  in __acpi_device_wakeup_enable()
769 			acpi_disable_gpe(wakeup->gpe_device, wakeup->gpe_number);  in __acpi_device_wakeup_enable()
770 			wakeup->enable_count = 0;  in __acpi_device_wakeup_enable()
775 	if (wakeup->enable_count > 0)  in __acpi_device_wakeup_enable()
778 	status = acpi_enable_gpe(wakeup->gpe_device, wakeup->gpe_number);  in __acpi_device_wakeup_enable()
781 		error = -EIO;  in __acpi_device_wakeup_enable()
785 	acpi_handle_debug(adev->handle, "GPE%2X enabled for wakeup\n",  in __acpi_device_wakeup_enable()
786 			  (unsigned int)wakeup->gpe_number);  in __acpi_device_wakeup_enable()
789 	if (wakeup->enable_count < INT_MAX)  in __acpi_device_wakeup_enable()
790 		wakeup->enable_count++;  in __acpi_device_wakeup_enable()
792 		acpi_handle_info(adev->handle, "Wakeup enable count out of bounds!\n");  in __acpi_device_wakeup_enable()
800  * acpi_device_wakeup_enable - Enable wakeup functionality for device.
806  * power for it.
817  * acpi_device_wakeup_disable - Disable wakeup functionality for device.
818  * @adev: ACPI device to disable wakeup functionality for.
820  * Disable the GPE associated with @adev and disable wakeup power for it.
827 	struct acpi_device_wakeup *wakeup = &adev->wakeup;  in acpi_device_wakeup_disable()
831 	if (!wakeup->enable_count)  in acpi_device_wakeup_disable()
834 	acpi_disable_gpe(wakeup->gpe_device, wakeup->gpe_number);  in acpi_device_wakeup_disable()
837 	wakeup->enable_count--;  in acpi_device_wakeup_disable()
844  * acpi_pm_set_device_wakeup - Enable/disable remote wakeup for given device.
845  * @dev: Device to enable/disable to generate wakeup events.
846  * @enable: Whether to enable or disable the wakeup functionality.
856 		return -ENODEV;  in acpi_pm_set_device_wakeup()
860 		return -EINVAL;  in acpi_pm_set_device_wakeup()
877  * acpi_dev_pm_low_power - Put ACPI device into a low-power state.
878  * @dev: Device to put into a low-power state.
895  * acpi_dev_pm_full_power - Put ACPI device into the full-power state.
896  * @adev: ACPI device node to put into the full-power state.
905  * acpi_dev_suspend - Put device into a low-power state using ACPI.
906  * @dev: Device to put into a low-power state.
909  * Put the given device into a low-power state using the standard ACPI
912  * the power state of the device.
926 			return -EAGAIN;  in acpi_dev_suspend()
940  * acpi_dev_resume - Put device into the full-power state using ACPI.
941  * @dev: Device to put into the full-power state.
943  * Put the given device into the full-power state using the standard ACPI
944  * mechanism.  Set the power state of the device to ACPI D0 and disable wakeup.
961  * acpi_subsys_runtime_suspend - Suspend device using ACPI.
965  * it into a runtime low-power state.
976  * acpi_subsys_runtime_resume - Resume device using ACPI.
979  * Use ACPI to put the given device into the full-power state and carry out the
996 	if (!pm_runtime_suspended(dev) || !adev || (adev->wakeup.flags.valid &&  in acpi_dev_needs_resume()
997 	    device_may_wakeup(dev) != !!adev->wakeup.prepare_count))  in acpi_dev_needs_resume()
1003 	if (adev->power.flags.dsw_present)  in acpi_dev_needs_resume()
1010 	return state != adev->power.state;  in acpi_dev_needs_resume()
1014  * acpi_subsys_prepare - Prepare device for system transition to a sleep state.
1021 	if (dev->driver && dev->driver->pm && dev->driver->pm->prepare) {  in acpi_subsys_prepare()
1022 		int ret = dev->driver->pm->prepare(dev);  in acpi_subsys_prepare()
1036  * acpi_subsys_complete - Finalize device's resume during system resume.
1043 	 * If the device had been runtime-suspended before the system went into  in acpi_subsys_complete()
1053  * acpi_subsys_suspend - Run the device driver's suspend callback.
1057  * system suspend callbacks, unless the driver can cope with runtime-suspended
1058  * devices during system suspend and there are no ACPI-specific reasons for
1072  * acpi_subsys_suspend_late - Suspend device using ACPI.
1076  * it into a low-power state during system transition into a sleep state.
1091  * acpi_subsys_suspend_noirq - Run the device driver's "noirq" suspend callback.
1106 	 * If the target system sleep state is suspend-to-idle, it is sufficient  in acpi_subsys_suspend_noirq()
1113 		dev->power.may_skip_resume = false;  in acpi_subsys_suspend_noirq()
1120  * acpi_subsys_resume_noirq - Run the device driver's "noirq" resume callback.
1132  * acpi_subsys_resume_early - Resume device using ACPI.
1135  * Use ACPI to put the given device into the full-power state and carry out the
1138  * handler, or does not define power operations at all. Otherwise powering up
1143 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;  in acpi_subsys_resume_early()
1149 	if (pm && !pm->resume_early) {  in acpi_subsys_resume_early()
1159  * acpi_subsys_resume - Resume device using ACPI.
1162  * Use ACPI to put the given device into the full-power state if it has not been
1168 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;  in acpi_subsys_resume()
1171 	if (!dev_pm_skip_resume(dev) && pm && !pm->resume_early) {  in acpi_subsys_resume()
1180  * acpi_subsys_freeze - Run the device driver's freeze callback.
1186 	 * Resume all runtime-suspended devices before creating a snapshot  in acpi_subsys_freeze()
1189 	 * put into the runtime-active metastate during system resume anyway,  in acpi_subsys_freeze()
1200  * acpi_subsys_restore_early - Restore device using ACPI.
1212  * acpi_subsys_poweroff - Run the device driver's poweroff callback.
1216  * system poweroff callbacks, unless the driver can cope with runtime-suspended
1217  * devices during system suspend and there are no ACPI-specific reasons for
1231  * acpi_subsys_poweroff_late - Run the device driver's poweroff callback.
1235  * it into a low-power state during system transition into a sleep state.
1252  * acpi_subsys_poweroff_noirq - Run the driver's "noirq" poweroff callback.
1287  * acpi_dev_pm_detach - Remove ACPI power management from the device.
1289  * @power_off: Whether or not to try to remove power from the device.
1292  * notifier.  If @power_off is set, additionally remove power from the device if
1295  * Callers must ensure proper synchronization of this function with power
1302 	if (adev && dev->pm_domain == &acpi_general_pm_domain) {  in acpi_dev_pm_detach()
1310 			 * choice of the low-power state to put the device into.  in acpi_dev_pm_detach()
1321  * acpi_dev_pm_attach - Prepare device for ACPI power management.
1323  * @power_on: Whether or not to power on the device.
1330  * This assumes that the @dev's bus type uses generic power management callbacks
1331  * (or doesn't use any power management callbacks at all).
1333  * Callers must ensure proper synchronization of this function with power
1340 	 * because they require special power management handling incompatible  in acpi_dev_pm_attach()
1353 	 * Only attach the power domain to the first device if the  in acpi_dev_pm_attach()
1354 	 * companion is shared by multiple. This is to prevent doing power  in acpi_dev_pm_attach()
1367 	dev->pm_domain->detach = acpi_dev_pm_detach;  in acpi_dev_pm_attach()
1373  * acpi_storage_d3 - Check if D3 should be used in the suspend path
1383  * applied to the PCIe slot and plugging in a non-storage device the