File-copy from v4.4.100

This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Please refer to that tree for all history prior to this point.

Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/drivers/acpi/device_pm.c b/drivers/acpi/device_pm.c
new file mode 100644
index 0000000..08a02cd
--- /dev/null
+++ b/drivers/acpi/device_pm.c
@@ -0,0 +1,1124 @@
+/*
+ * drivers/acpi/device_pm.c - ACPI device power management routines.
+ *
+ * Copyright (C) 2012, Intel Corp.
+ * Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2 as published
+ *  by the Free Software Foundation.
+ *
+ *  This program is distributed in the hope that it will be useful, but
+ *  WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ *  General Public License for more details.
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ */
+
+#include <linux/acpi.h>
+#include <linux/export.h>
+#include <linux/mutex.h>
+#include <linux/pm_qos.h>
+#include <linux/pm_runtime.h>
+
+#include "internal.h"
+
+#define _COMPONENT	ACPI_POWER_COMPONENT
+ACPI_MODULE_NAME("device_pm");
+
+/**
+ * acpi_power_state_string - String representation of ACPI device power state.
+ * @state: ACPI device power state to return the string representation of.
+ */
+const char *acpi_power_state_string(int state)
+{
+	switch (state) {
+	case ACPI_STATE_D0:
+		return "D0";
+	case ACPI_STATE_D1:
+		return "D1";
+	case ACPI_STATE_D2:
+		return "D2";
+	case ACPI_STATE_D3_HOT:
+		return "D3hot";
+	case ACPI_STATE_D3_COLD:
+		return "D3cold";
+	default:
+		return "(unknown)";
+	}
+}
+
+/**
+ * acpi_device_get_power - Get power state of an ACPI device.
+ * @device: Device to get the power state of.
+ * @state: Place to store the power state of the device.
+ *
+ * This function does not update the device's power.state field, but it may
+ * update its parent's power.state field (when the parent's power state is
+ * unknown and the device's power state turns out to be D0).
+ */
+int acpi_device_get_power(struct acpi_device *device, int *state)
+{
+	int result = ACPI_STATE_UNKNOWN;
+
+	if (!device || !state)
+		return -EINVAL;
+
+	if (!device->flags.power_manageable) {
+		/* TBD: Non-recursive algorithm for walking up hierarchy. */
+		*state = device->parent ?
+			device->parent->power.state : ACPI_STATE_D0;
+		goto out;
+	}
+
+	/*
+	 * Get the device's power state from power resources settings and _PSC,
+	 * if available.
+	 */
+	if (device->power.flags.power_resources) {
+		int error = acpi_power_get_inferred_state(device, &result);
+		if (error)
+			return error;
+	}
+	if (device->power.flags.explicit_get) {
+		acpi_handle handle = device->handle;
+		unsigned long long psc;
+		acpi_status status;
+
+		status = acpi_evaluate_integer(handle, "_PSC", NULL, &psc);
+		if (ACPI_FAILURE(status))
+			return -ENODEV;
+
+		/*
+		 * The power resources settings may indicate a power state
+		 * shallower than the actual power state of the device, because
+		 * the same power resources may be referenced by other devices.
+		 *
+		 * For systems predating ACPI 4.0 we assume that D3hot is the
+		 * deepest state that can be supported.
+		 */
+		if (psc > result && psc < ACPI_STATE_D3_COLD)
+			result = psc;
+		else if (result == ACPI_STATE_UNKNOWN)
+			result = psc > ACPI_STATE_D2 ? ACPI_STATE_D3_HOT : psc;
+	}
+
+	/*
+	 * If we were unsure about the device parent's power state up to this
+	 * point, the fact that the device is in D0 implies that the parent has
+	 * to be in D0 too, except if ignore_parent is set.
+	 */
+	if (!device->power.flags.ignore_parent && device->parent
+	    && device->parent->power.state == ACPI_STATE_UNKNOWN
+	    && result == ACPI_STATE_D0)
+		device->parent->power.state = ACPI_STATE_D0;
+
+	*state = result;
+
+ out:
+	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] power state is %s\n",
+			  device->pnp.bus_id, acpi_power_state_string(*state)));
+
+	return 0;
+}
+
+static int acpi_dev_pm_explicit_set(struct acpi_device *adev, int state)
+{
+	if (adev->power.states[state].flags.explicit_set) {
+		char method[5] = { '_', 'P', 'S', '0' + state, '\0' };
+		acpi_status status;
+
+		status = acpi_evaluate_object(adev->handle, method, NULL, NULL);
+		if (ACPI_FAILURE(status))
+			return -ENODEV;
+	}
+	return 0;
+}
+
+/**
+ * acpi_device_set_power - Set power state of an ACPI device.
+ * @device: Device to set the power state of.
+ * @state: New power state to set.
+ *
+ * Callers must ensure that the device is power manageable before using this
+ * function.
+ */
+int acpi_device_set_power(struct acpi_device *device, int state)
+{
+	int target_state = state;
+	int result = 0;
+
+	if (!device || !device->flags.power_manageable
+	    || (state < ACPI_STATE_D0) || (state > ACPI_STATE_D3_COLD))
+		return -EINVAL;
+
+	/* Make sure this is a valid target state */
+
+	if (state == device->power.state) {
+		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] already in %s\n",
+				  device->pnp.bus_id,
+				  acpi_power_state_string(state)));
+		return 0;
+	}
+
+	if (state == ACPI_STATE_D3_COLD) {
+		/*
+		 * For transitions to D3cold we need to execute _PS3 and then
+		 * possibly drop references to the power resources in use.
+		 */
+		state = ACPI_STATE_D3_HOT;
+		/* If _PR3 is not available, use D3hot as the target state. */
+		if (!device->power.states[ACPI_STATE_D3_COLD].flags.valid)
+			target_state = state;
+	} else if (!device->power.states[state].flags.valid) {
+		dev_warn(&device->dev, "Power state %s not supported\n",
+			 acpi_power_state_string(state));
+		return -ENODEV;
+	}
+
+	if (!device->power.flags.ignore_parent &&
+	    device->parent && (state < device->parent->power.state)) {
+		dev_warn(&device->dev,
+			 "Cannot transition to power state %s for parent in %s\n",
+			 acpi_power_state_string(state),
+			 acpi_power_state_string(device->parent->power.state));
+		return -ENODEV;
+	}
+
+	/*
+	 * Transition Power
+	 * ----------------
+	 * In accordance with ACPI 6, _PSx is executed before manipulating power
+	 * resources, unless the target state is D0, in which case _PS0 is
+	 * supposed to be executed after turning the power resources on.
+	 */
+	if (state > ACPI_STATE_D0) {
+		/*
+		 * According to ACPI 6, devices cannot go from lower-power
+		 * (deeper) states to higher-power (shallower) states.
+		 */
+		if (state < device->power.state) {
+			dev_warn(&device->dev, "Cannot transition from %s to %s\n",
+				 acpi_power_state_string(device->power.state),
+				 acpi_power_state_string(state));
+			return -ENODEV;
+		}
+
+		result = acpi_dev_pm_explicit_set(device, state);
+		if (result)
+			goto end;
+
+		if (device->power.flags.power_resources)
+			result = acpi_power_transition(device, target_state);
+	} else {
+		if (device->power.flags.power_resources) {
+			result = acpi_power_transition(device, ACPI_STATE_D0);
+			if (result)
+				goto end;
+		}
+		result = acpi_dev_pm_explicit_set(device, ACPI_STATE_D0);
+	}
+
+ end:
+	if (result) {
+		dev_warn(&device->dev, "Failed to change power state to %s\n",
+			 acpi_power_state_string(state));
+	} else {
+		device->power.state = target_state;
+		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+				  "Device [%s] transitioned to %s\n",
+				  device->pnp.bus_id,
+				  acpi_power_state_string(state)));
+	}
+
+	return result;
+}
+EXPORT_SYMBOL(acpi_device_set_power);
+
+int acpi_bus_set_power(acpi_handle handle, int state)
+{
+	struct acpi_device *device;
+	int result;
+
+	result = acpi_bus_get_device(handle, &device);
+	if (result)
+		return result;
+
+	return acpi_device_set_power(device, state);
+}
+EXPORT_SYMBOL(acpi_bus_set_power);
+
+int acpi_bus_init_power(struct acpi_device *device)
+{
+	int state;
+	int result;
+
+	if (!device)
+		return -EINVAL;
+
+	device->power.state = ACPI_STATE_UNKNOWN;
+	if (!acpi_device_is_present(device))
+		return -ENXIO;
+
+	result = acpi_device_get_power(device, &state);
+	if (result)
+		return result;
+
+	if (state < ACPI_STATE_D3_COLD && device->power.flags.power_resources) {
+		/* Reference count the power resources. */
+		result = acpi_power_on_resources(device, state);
+		if (result)
+			return result;
+
+		if (state == ACPI_STATE_D0) {
+			/*
+			 * If _PSC is not present and the state inferred from
+			 * power resources appears to be D0, it still may be
+			 * necessary to execute _PS0 at this point, because
+			 * another device using the same power resources may
+			 * have been put into D0 previously and that's why we
+			 * see D0 here.
+			 */
+			result = acpi_dev_pm_explicit_set(device, state);
+			if (result)
+				return result;
+		}
+	} else if (state == ACPI_STATE_UNKNOWN) {
+		/*
+		 * No power resources and missing _PSC?  Cross fingers and make
+		 * it D0 in hope that this is what the BIOS put the device into.
+		 * [We tried to force D0 here by executing _PS0, but that broke
+		 * Toshiba P870-303 in a nasty way.]
+		 */
+		state = ACPI_STATE_D0;
+	}
+	device->power.state = state;
+	return 0;
+}
+
+/**
+ * acpi_device_fix_up_power - Force device with missing _PSC into D0.
+ * @device: Device object whose power state is to be fixed up.
+ *
+ * Devices without power resources and _PSC, but having _PS0 and _PS3 defined,
+ * are assumed to be put into D0 by the BIOS.  However, in some cases that may
+ * not be the case and this function should be used then.
+ */
+int acpi_device_fix_up_power(struct acpi_device *device)
+{
+	int ret = 0;
+
+	if (!device->power.flags.power_resources
+	    && !device->power.flags.explicit_get
+	    && device->power.state == ACPI_STATE_D0)
+		ret = acpi_dev_pm_explicit_set(device, ACPI_STATE_D0);
+
+	return ret;
+}
+
+int acpi_device_update_power(struct acpi_device *device, int *state_p)
+{
+	int state;
+	int result;
+
+	if (device->power.state == ACPI_STATE_UNKNOWN) {
+		result = acpi_bus_init_power(device);
+		if (!result && state_p)
+			*state_p = device->power.state;
+
+		return result;
+	}
+
+	result = acpi_device_get_power(device, &state);
+	if (result)
+		return result;
+
+	if (state == ACPI_STATE_UNKNOWN) {
+		state = ACPI_STATE_D0;
+		result = acpi_device_set_power(device, state);
+		if (result)
+			return result;
+	} else {
+		if (device->power.flags.power_resources) {
+			/*
+			 * We don't need to really switch the state, bu we need
+			 * to update the power resources' reference counters.
+			 */
+			result = acpi_power_transition(device, state);
+			if (result)
+				return result;
+		}
+		device->power.state = state;
+	}
+	if (state_p)
+		*state_p = state;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(acpi_device_update_power);
+
+int acpi_bus_update_power(acpi_handle handle, int *state_p)
+{
+	struct acpi_device *device;
+	int result;
+
+	result = acpi_bus_get_device(handle, &device);
+	return result ? result : acpi_device_update_power(device, state_p);
+}
+EXPORT_SYMBOL_GPL(acpi_bus_update_power);
+
+bool acpi_bus_power_manageable(acpi_handle handle)
+{
+	struct acpi_device *device;
+	int result;
+
+	result = acpi_bus_get_device(handle, &device);
+	return result ? false : device->flags.power_manageable;
+}
+EXPORT_SYMBOL(acpi_bus_power_manageable);
+
+#ifdef CONFIG_PM
+static DEFINE_MUTEX(acpi_pm_notifier_lock);
+
+static void acpi_pm_notify_handler(acpi_handle handle, u32 val, void *not_used)
+{
+	struct acpi_device *adev;
+
+	if (val != ACPI_NOTIFY_DEVICE_WAKE)
+		return;
+
+	adev = acpi_bus_get_acpi_device(handle);
+	if (!adev)
+		return;
+
+	mutex_lock(&acpi_pm_notifier_lock);
+
+	if (adev->wakeup.flags.notifier_present) {
+		__pm_wakeup_event(adev->wakeup.ws, 0);
+		if (adev->wakeup.context.work.func)
+			queue_pm_work(&adev->wakeup.context.work);
+	}
+
+	mutex_unlock(&acpi_pm_notifier_lock);
+
+	acpi_bus_put_acpi_device(adev);
+}
+
+/**
+ * acpi_add_pm_notifier - Register PM notify handler for given ACPI device.
+ * @adev: ACPI device to add the notify handler for.
+ * @dev: Device to generate a wakeup event for while handling the notification.
+ * @work_func: Work function to execute when handling the notification.
+ *
+ * NOTE: @adev need not be a run-wake or wakeup device to be a valid source of
+ * PM wakeup events.  For example, wakeup events may be generated for bridges
+ * if one of the devices below the bridge is signaling wakeup, even if the
+ * bridge itself doesn't have a wakeup GPE associated with it.
+ */
+acpi_status acpi_add_pm_notifier(struct acpi_device *adev, struct device *dev,
+				 void (*work_func)(struct work_struct *work))
+{
+	acpi_status status = AE_ALREADY_EXISTS;
+
+	if (!dev && !work_func)
+		return AE_BAD_PARAMETER;
+
+	mutex_lock(&acpi_pm_notifier_lock);
+
+	if (adev->wakeup.flags.notifier_present)
+		goto out;
+
+	adev->wakeup.ws = wakeup_source_register(dev_name(&adev->dev));
+	adev->wakeup.context.dev = dev;
+	if (work_func)
+		INIT_WORK(&adev->wakeup.context.work, work_func);
+
+	status = acpi_install_notify_handler(adev->handle, ACPI_SYSTEM_NOTIFY,
+					     acpi_pm_notify_handler, NULL);
+	if (ACPI_FAILURE(status))
+		goto out;
+
+	adev->wakeup.flags.notifier_present = true;
+
+ out:
+	mutex_unlock(&acpi_pm_notifier_lock);
+	return status;
+}
+
+/**
+ * acpi_remove_pm_notifier - Unregister PM notifier from given ACPI device.
+ * @adev: ACPI device to remove the notifier from.
+ */
+acpi_status acpi_remove_pm_notifier(struct acpi_device *adev)
+{
+	acpi_status status = AE_BAD_PARAMETER;
+
+	mutex_lock(&acpi_pm_notifier_lock);
+
+	if (!adev->wakeup.flags.notifier_present)
+		goto out;
+
+	status = acpi_remove_notify_handler(adev->handle,
+					    ACPI_SYSTEM_NOTIFY,
+					    acpi_pm_notify_handler);
+	if (ACPI_FAILURE(status))
+		goto out;
+
+	if (adev->wakeup.context.work.func) {
+		cancel_work_sync(&adev->wakeup.context.work);
+		adev->wakeup.context.work.func = NULL;
+	}
+	adev->wakeup.context.dev = NULL;
+	wakeup_source_unregister(adev->wakeup.ws);
+
+	adev->wakeup.flags.notifier_present = false;
+
+ out:
+	mutex_unlock(&acpi_pm_notifier_lock);
+	return status;
+}
+
+bool acpi_bus_can_wakeup(acpi_handle handle)
+{
+	struct acpi_device *device;
+	int result;
+
+	result = acpi_bus_get_device(handle, &device);
+	return result ? false : device->wakeup.flags.valid;
+}
+EXPORT_SYMBOL(acpi_bus_can_wakeup);
+
+/**
+ * acpi_dev_pm_get_state - Get preferred power state of ACPI device.
+ * @dev: Device whose preferred target power state to return.
+ * @adev: ACPI device node corresponding to @dev.
+ * @target_state: System state to match the resultant device state.
+ * @d_min_p: Location to store the highest power state available to the device.
+ * @d_max_p: Location to store the lowest power state available to the device.
+ *
+ * Find the lowest power (highest number) and highest power (lowest number) ACPI
+ * device power states that the device can be in while the system is in the
+ * state represented by @target_state.  Store the integer numbers representing
+ * those stats in the memory locations pointed to by @d_max_p and @d_min_p,
+ * respectively.
+ *
+ * Callers must ensure that @dev and @adev are valid pointers and that @adev
+ * actually corresponds to @dev before using this function.
+ *
+ * Returns 0 on success or -ENODATA when one of the ACPI methods fails or
+ * returns a value that doesn't make sense.  The memory locations pointed to by
+ * @d_max_p and @d_min_p are only modified on success.
+ */
+static int acpi_dev_pm_get_state(struct device *dev, struct acpi_device *adev,
+				 u32 target_state, int *d_min_p, int *d_max_p)
+{
+	char method[] = { '_', 'S', '0' + target_state, 'D', '\0' };
+	acpi_handle handle = adev->handle;
+	unsigned long long ret;
+	int d_min, d_max;
+	bool wakeup = false;
+	acpi_status status;
+
+	/*
+	 * If the system state is S0, the lowest power state the device can be
+	 * in is D3cold, unless the device has _S0W and is supposed to signal
+	 * wakeup, in which case the return value of _S0W has to be used as the
+	 * lowest power state available to the device.
+	 */
+	d_min = ACPI_STATE_D0;
+	d_max = ACPI_STATE_D3_COLD;
+
+	/*
+	 * If present, _SxD methods return the minimum D-state (highest power
+	 * state) we can use for the corresponding S-states.  Otherwise, the
+	 * minimum D-state is D0 (ACPI 3.x).
+	 */
+	if (target_state > ACPI_STATE_S0) {
+		/*
+		 * We rely on acpi_evaluate_integer() not clobbering the integer
+		 * provided if AE_NOT_FOUND is returned.
+		 */
+		ret = d_min;
+		status = acpi_evaluate_integer(handle, method, NULL, &ret);
+		if ((ACPI_FAILURE(status) && status != AE_NOT_FOUND)
+		    || ret > ACPI_STATE_D3_COLD)
+			return -ENODATA;
+
+		/*
+		 * We need to handle legacy systems where D3hot and D3cold are
+		 * the same and 3 is returned in both cases, so fall back to
+		 * D3cold if D3hot is not a valid state.
+		 */
+		if (!adev->power.states[ret].flags.valid) {
+			if (ret == ACPI_STATE_D3_HOT)
+				ret = ACPI_STATE_D3_COLD;
+			else
+				return -ENODATA;
+		}
+		d_min = ret;
+		wakeup = device_may_wakeup(dev) && adev->wakeup.flags.valid
+			&& adev->wakeup.sleep_state >= target_state;
+	} else if (dev_pm_qos_flags(dev, PM_QOS_FLAG_REMOTE_WAKEUP) !=
+			PM_QOS_FLAGS_NONE) {
+		wakeup = adev->wakeup.flags.valid;
+	}
+
+	/*
+	 * If _PRW says we can wake up the system from the target sleep state,
+	 * the D-state returned by _SxD is sufficient for that (we assume a
+	 * wakeup-aware driver if wake is set).  Still, if _SxW exists
+	 * (ACPI 3.x), it should return the maximum (lowest power) D-state that
+	 * can wake the system.  _S0W may be valid, too.
+	 */
+	if (wakeup) {
+		method[3] = 'W';
+		status = acpi_evaluate_integer(handle, method, NULL, &ret);
+		if (status == AE_NOT_FOUND) {
+			if (target_state > ACPI_STATE_S0)
+				d_max = d_min;
+		} else if (ACPI_SUCCESS(status) && ret <= ACPI_STATE_D3_COLD) {
+			/* Fall back to D3cold if ret is not a valid state. */
+			if (!adev->power.states[ret].flags.valid)
+				ret = ACPI_STATE_D3_COLD;
+
+			d_max = ret > d_min ? ret : d_min;
+		} else {
+			return -ENODATA;
+		}
+	}
+
+	if (d_min_p)
+		*d_min_p = d_min;
+
+	if (d_max_p)
+		*d_max_p = d_max;
+
+	return 0;
+}
+
+/**
+ * acpi_pm_device_sleep_state - Get preferred power state of ACPI device.
+ * @dev: Device whose preferred target power state to return.
+ * @d_min_p: Location to store the upper limit of the allowed states range.
+ * @d_max_in: Deepest low-power state to take into consideration.
+ * Return value: Preferred power state of the device on success, -ENODEV
+ * if there's no 'struct acpi_device' for @dev, -EINVAL if @d_max_in is
+ * incorrect, or -ENODATA on ACPI method failure.
+ *
+ * The caller must ensure that @dev is valid before using this function.
+ */
+int acpi_pm_device_sleep_state(struct device *dev, int *d_min_p, int d_max_in)
+{
+	struct acpi_device *adev;
+	int ret, d_min, d_max;
+
+	if (d_max_in < ACPI_STATE_D0 || d_max_in > ACPI_STATE_D3_COLD)
+		return -EINVAL;
+
+	if (d_max_in > ACPI_STATE_D2) {
+		enum pm_qos_flags_status stat;
+
+		stat = dev_pm_qos_flags(dev, PM_QOS_FLAG_NO_POWER_OFF);
+		if (stat == PM_QOS_FLAGS_ALL)
+			d_max_in = ACPI_STATE_D2;
+	}
+
+	adev = ACPI_COMPANION(dev);
+	if (!adev) {
+		dev_dbg(dev, "ACPI companion missing in %s!\n", __func__);
+		return -ENODEV;
+	}
+
+	ret = acpi_dev_pm_get_state(dev, adev, acpi_target_system_state(),
+				    &d_min, &d_max);
+	if (ret)
+		return ret;
+
+	if (d_max_in < d_min)
+		return -EINVAL;
+
+	if (d_max > d_max_in) {
+		for (d_max = d_max_in; d_max > d_min; d_max--) {
+			if (adev->power.states[d_max].flags.valid)
+				break;
+		}
+	}
+
+	if (d_min_p)
+		*d_min_p = d_min;
+
+	return d_max;
+}
+EXPORT_SYMBOL(acpi_pm_device_sleep_state);
+
+/**
+ * acpi_pm_notify_work_func - ACPI devices wakeup notification work function.
+ * @work: Work item to handle.
+ */
+static void acpi_pm_notify_work_func(struct work_struct *work)
+{
+	struct device *dev;
+
+	dev = container_of(work, struct acpi_device_wakeup_context, work)->dev;
+	if (dev) {
+		pm_wakeup_event(dev, 0);
+		pm_runtime_resume(dev);
+	}
+}
+
+/**
+ * acpi_device_wakeup - Enable/disable wakeup functionality for device.
+ * @adev: ACPI device to enable/disable wakeup functionality for.
+ * @target_state: State the system is transitioning into.
+ * @enable: Whether to enable or disable the wakeup functionality.
+ *
+ * Enable/disable the GPE associated with @adev so that it can generate
+ * wakeup signals for the device in response to external (remote) events and
+ * enable/disable device wakeup power.
+ *
+ * Callers must ensure that @adev is a valid ACPI device node before executing
+ * this function.
+ */
+static int acpi_device_wakeup(struct acpi_device *adev, u32 target_state,
+			      bool enable)
+{
+	struct acpi_device_wakeup *wakeup = &adev->wakeup;
+
+	if (enable) {
+		acpi_status res;
+		int error;
+
+		error = acpi_enable_wakeup_device_power(adev, target_state);
+		if (error)
+			return error;
+
+		if (adev->wakeup.flags.enabled)
+			return 0;
+
+		res = acpi_enable_gpe(wakeup->gpe_device, wakeup->gpe_number);
+		if (ACPI_SUCCESS(res)) {
+			adev->wakeup.flags.enabled = 1;
+		} else {
+			acpi_disable_wakeup_device_power(adev);
+			return -EIO;
+		}
+	} else {
+		if (adev->wakeup.flags.enabled) {
+			acpi_disable_gpe(wakeup->gpe_device, wakeup->gpe_number);
+			adev->wakeup.flags.enabled = 0;
+		}
+		acpi_disable_wakeup_device_power(adev);
+	}
+	return 0;
+}
+
+/**
+ * acpi_pm_device_run_wake - Enable/disable remote wakeup for given device.
+ * @dev: Device to enable/disable the platform to wake up.
+ * @enable: Whether to enable or disable the wakeup functionality.
+ */
+int acpi_pm_device_run_wake(struct device *phys_dev, bool enable)
+{
+	struct acpi_device *adev;
+
+	if (!device_run_wake(phys_dev))
+		return -EINVAL;
+
+	adev = ACPI_COMPANION(phys_dev);
+	if (!adev) {
+		dev_dbg(phys_dev, "ACPI companion missing in %s!\n", __func__);
+		return -ENODEV;
+	}
+
+	return acpi_device_wakeup(adev, ACPI_STATE_S0, enable);
+}
+EXPORT_SYMBOL(acpi_pm_device_run_wake);
+
+#ifdef CONFIG_PM_SLEEP
+/**
+ * acpi_pm_device_sleep_wake - Enable or disable device to wake up the system.
+ * @dev: Device to enable/desible to wake up the system from sleep states.
+ * @enable: Whether to enable or disable @dev to wake up the system.
+ */
+int acpi_pm_device_sleep_wake(struct device *dev, bool enable)
+{
+	struct acpi_device *adev;
+	int error;
+
+	if (!device_can_wakeup(dev))
+		return -EINVAL;
+
+	adev = ACPI_COMPANION(dev);
+	if (!adev) {
+		dev_dbg(dev, "ACPI companion missing in %s!\n", __func__);
+		return -ENODEV;
+	}
+
+	error = acpi_device_wakeup(adev, acpi_target_system_state(), enable);
+	if (!error)
+		dev_info(dev, "System wakeup %s by ACPI\n",
+				enable ? "enabled" : "disabled");
+
+	return error;
+}
+#endif /* CONFIG_PM_SLEEP */
+
+/**
+ * acpi_dev_pm_low_power - Put ACPI device into a low-power state.
+ * @dev: Device to put into a low-power state.
+ * @adev: ACPI device node corresponding to @dev.
+ * @system_state: System state to choose the device state for.
+ */
+static int acpi_dev_pm_low_power(struct device *dev, struct acpi_device *adev,
+				 u32 system_state)
+{
+	int ret, state;
+
+	if (!acpi_device_power_manageable(adev))
+		return 0;
+
+	ret = acpi_dev_pm_get_state(dev, adev, system_state, NULL, &state);
+	return ret ? ret : acpi_device_set_power(adev, state);
+}
+
+/**
+ * acpi_dev_pm_full_power - Put ACPI device into the full-power state.
+ * @adev: ACPI device node to put into the full-power state.
+ */
+static int acpi_dev_pm_full_power(struct acpi_device *adev)
+{
+	return acpi_device_power_manageable(adev) ?
+		acpi_device_set_power(adev, ACPI_STATE_D0) : 0;
+}
+
+/**
+ * acpi_dev_runtime_suspend - Put device into a low-power state using ACPI.
+ * @dev: Device to put into a low-power state.
+ *
+ * Put the given device into a runtime low-power state using the standard ACPI
+ * mechanism.  Set up remote wakeup if desired, choose the state to put the
+ * device into (this checks if remote wakeup is expected to work too), and set
+ * the power state of the device.
+ */
+int acpi_dev_runtime_suspend(struct device *dev)
+{
+	struct acpi_device *adev = ACPI_COMPANION(dev);
+	bool remote_wakeup;
+	int error;
+
+	if (!adev)
+		return 0;
+
+	remote_wakeup = dev_pm_qos_flags(dev, PM_QOS_FLAG_REMOTE_WAKEUP) >
+				PM_QOS_FLAGS_NONE;
+	error = acpi_device_wakeup(adev, ACPI_STATE_S0, remote_wakeup);
+	if (remote_wakeup && error)
+		return -EAGAIN;
+
+	error = acpi_dev_pm_low_power(dev, adev, ACPI_STATE_S0);
+	if (error)
+		acpi_device_wakeup(adev, ACPI_STATE_S0, false);
+
+	return error;
+}
+EXPORT_SYMBOL_GPL(acpi_dev_runtime_suspend);
+
+/**
+ * acpi_dev_runtime_resume - Put device into the full-power state using ACPI.
+ * @dev: Device to put into the full-power state.
+ *
+ * Put the given device into the full-power state using the standard ACPI
+ * mechanism at run time.  Set the power state of the device to ACPI D0 and
+ * disable remote wakeup.
+ */
+int acpi_dev_runtime_resume(struct device *dev)
+{
+	struct acpi_device *adev = ACPI_COMPANION(dev);
+	int error;
+
+	if (!adev)
+		return 0;
+
+	error = acpi_dev_pm_full_power(adev);
+	acpi_device_wakeup(adev, ACPI_STATE_S0, false);
+	return error;
+}
+EXPORT_SYMBOL_GPL(acpi_dev_runtime_resume);
+
+/**
+ * acpi_subsys_runtime_suspend - Suspend device using ACPI.
+ * @dev: Device to suspend.
+ *
+ * Carry out the generic runtime suspend procedure for @dev and use ACPI to put
+ * it into a runtime low-power state.
+ */
+int acpi_subsys_runtime_suspend(struct device *dev)
+{
+	int ret = pm_generic_runtime_suspend(dev);
+	return ret ? ret : acpi_dev_runtime_suspend(dev);
+}
+EXPORT_SYMBOL_GPL(acpi_subsys_runtime_suspend);
+
+/**
+ * acpi_subsys_runtime_resume - Resume device using ACPI.
+ * @dev: Device to Resume.
+ *
+ * Use ACPI to put the given device into the full-power state and carry out the
+ * generic runtime resume procedure for it.
+ */
+int acpi_subsys_runtime_resume(struct device *dev)
+{
+	int ret = acpi_dev_runtime_resume(dev);
+	return ret ? ret : pm_generic_runtime_resume(dev);
+}
+EXPORT_SYMBOL_GPL(acpi_subsys_runtime_resume);
+
+#ifdef CONFIG_PM_SLEEP
+/**
+ * acpi_dev_suspend_late - Put device into a low-power state using ACPI.
+ * @dev: Device to put into a low-power state.
+ *
+ * Put the given device into a low-power state during system transition to a
+ * sleep state using the standard ACPI mechanism.  Set up system wakeup if
+ * desired, choose the state to put the device into (this checks if system
+ * wakeup is expected to work too), and set the power state of the device.
+ */
+int acpi_dev_suspend_late(struct device *dev)
+{
+	struct acpi_device *adev = ACPI_COMPANION(dev);
+	u32 target_state;
+	bool wakeup;
+	int error;
+
+	if (!adev)
+		return 0;
+
+	target_state = acpi_target_system_state();
+	wakeup = device_may_wakeup(dev) && acpi_device_can_wakeup(adev);
+	error = acpi_device_wakeup(adev, target_state, wakeup);
+	if (wakeup && error)
+		return error;
+
+	error = acpi_dev_pm_low_power(dev, adev, target_state);
+	if (error)
+		acpi_device_wakeup(adev, ACPI_STATE_UNKNOWN, false);
+
+	return error;
+}
+EXPORT_SYMBOL_GPL(acpi_dev_suspend_late);
+
+/**
+ * acpi_dev_resume_early - Put device into the full-power state using ACPI.
+ * @dev: Device to put into the full-power state.
+ *
+ * Put the given device into the full-power state using the standard ACPI
+ * mechanism during system transition to the working state.  Set the power
+ * state of the device to ACPI D0 and disable remote wakeup.
+ */
+int acpi_dev_resume_early(struct device *dev)
+{
+	struct acpi_device *adev = ACPI_COMPANION(dev);
+	int error;
+
+	if (!adev)
+		return 0;
+
+	error = acpi_dev_pm_full_power(adev);
+	acpi_device_wakeup(adev, ACPI_STATE_UNKNOWN, false);
+	return error;
+}
+EXPORT_SYMBOL_GPL(acpi_dev_resume_early);
+
+/**
+ * acpi_subsys_prepare - Prepare device for system transition to a sleep state.
+ * @dev: Device to prepare.
+ */
+int acpi_subsys_prepare(struct device *dev)
+{
+	struct acpi_device *adev = ACPI_COMPANION(dev);
+	u32 sys_target;
+	int ret, state;
+
+	ret = pm_generic_prepare(dev);
+	if (ret < 0)
+		return ret;
+
+	if (!adev || !pm_runtime_suspended(dev)
+	    || device_may_wakeup(dev) != !!adev->wakeup.prepare_count)
+		return 0;
+
+	sys_target = acpi_target_system_state();
+	if (sys_target == ACPI_STATE_S0)
+		return 1;
+
+	if (adev->power.flags.dsw_present)
+		return 0;
+
+	ret = acpi_dev_pm_get_state(dev, adev, sys_target, NULL, &state);
+	return !ret && state == adev->power.state;
+}
+EXPORT_SYMBOL_GPL(acpi_subsys_prepare);
+
+/**
+ * acpi_subsys_suspend - Run the device driver's suspend callback.
+ * @dev: Device to handle.
+ *
+ * Follow PCI and resume devices suspended at run time before running their
+ * system suspend callbacks.
+ */
+int acpi_subsys_suspend(struct device *dev)
+{
+	pm_runtime_resume(dev);
+	return pm_generic_suspend(dev);
+}
+EXPORT_SYMBOL_GPL(acpi_subsys_suspend);
+
+/**
+ * acpi_subsys_suspend_late - Suspend device using ACPI.
+ * @dev: Device to suspend.
+ *
+ * Carry out the generic late suspend procedure for @dev and use ACPI to put
+ * it into a low-power state during system transition into a sleep state.
+ */
+int acpi_subsys_suspend_late(struct device *dev)
+{
+	int ret = pm_generic_suspend_late(dev);
+	return ret ? ret : acpi_dev_suspend_late(dev);
+}
+EXPORT_SYMBOL_GPL(acpi_subsys_suspend_late);
+
+/**
+ * acpi_subsys_resume_early - Resume device using ACPI.
+ * @dev: Device to Resume.
+ *
+ * Use ACPI to put the given device into the full-power state and carry out the
+ * generic early resume procedure for it during system transition into the
+ * working state.
+ */
+int acpi_subsys_resume_early(struct device *dev)
+{
+	int ret = acpi_dev_resume_early(dev);
+	return ret ? ret : pm_generic_resume_early(dev);
+}
+EXPORT_SYMBOL_GPL(acpi_subsys_resume_early);
+
+/**
+ * acpi_subsys_freeze - Run the device driver's freeze callback.
+ * @dev: Device to handle.
+ */
+int acpi_subsys_freeze(struct device *dev)
+{
+	/*
+	 * This used to be done in acpi_subsys_prepare() for all devices and
+	 * some drivers may depend on it, so do it here.  Ideally, however,
+	 * runtime-suspended devices should not be touched during freeze/thaw
+	 * transitions.
+	 */
+	pm_runtime_resume(dev);
+	return pm_generic_freeze(dev);
+}
+EXPORT_SYMBOL_GPL(acpi_subsys_freeze);
+
+#endif /* CONFIG_PM_SLEEP */
+
+static struct dev_pm_domain acpi_general_pm_domain = {
+	.ops = {
+		.runtime_suspend = acpi_subsys_runtime_suspend,
+		.runtime_resume = acpi_subsys_runtime_resume,
+#ifdef CONFIG_PM_SLEEP
+		.prepare = acpi_subsys_prepare,
+		.complete = pm_complete_with_resume_check,
+		.suspend = acpi_subsys_suspend,
+		.suspend_late = acpi_subsys_suspend_late,
+		.resume_early = acpi_subsys_resume_early,
+		.freeze = acpi_subsys_freeze,
+		.poweroff = acpi_subsys_suspend,
+		.poweroff_late = acpi_subsys_suspend_late,
+		.restore_early = acpi_subsys_resume_early,
+#endif
+	},
+};
+
+/**
+ * acpi_dev_pm_detach - Remove ACPI power management from the device.
+ * @dev: Device to take care of.
+ * @power_off: Whether or not to try to remove power from the device.
+ *
+ * Remove the device from the general ACPI PM domain and remove its wakeup
+ * notifier.  If @power_off is set, additionally remove power from the device if
+ * possible.
+ *
+ * Callers must ensure proper synchronization of this function with power
+ * management callbacks.
+ */
+static void acpi_dev_pm_detach(struct device *dev, bool power_off)
+{
+	struct acpi_device *adev = ACPI_COMPANION(dev);
+
+	if (adev && dev->pm_domain == &acpi_general_pm_domain) {
+		dev->pm_domain = NULL;
+		acpi_remove_pm_notifier(adev);
+		if (power_off) {
+			/*
+			 * If the device's PM QoS resume latency limit or flags
+			 * have been exposed to user space, they have to be
+			 * hidden at this point, so that they don't affect the
+			 * choice of the low-power state to put the device into.
+			 */
+			dev_pm_qos_hide_latency_limit(dev);
+			dev_pm_qos_hide_flags(dev);
+			acpi_device_wakeup(adev, ACPI_STATE_S0, false);
+			acpi_dev_pm_low_power(dev, adev, ACPI_STATE_S0);
+		}
+	}
+}
+
+/**
+ * acpi_dev_pm_attach - Prepare device for ACPI power management.
+ * @dev: Device to prepare.
+ * @power_on: Whether or not to power on the device.
+ *
+ * If @dev has a valid ACPI handle that has a valid struct acpi_device object
+ * attached to it, install a wakeup notification handler for the device and
+ * add it to the general ACPI PM domain.  If @power_on is set, the device will
+ * be put into the ACPI D0 state before the function returns.
+ *
+ * This assumes that the @dev's bus type uses generic power management callbacks
+ * (or doesn't use any power management callbacks at all).
+ *
+ * Callers must ensure proper synchronization of this function with power
+ * management callbacks.
+ */
+int acpi_dev_pm_attach(struct device *dev, bool power_on)
+{
+	struct acpi_device *adev = ACPI_COMPANION(dev);
+
+	if (!adev)
+		return -ENODEV;
+
+	if (dev->pm_domain)
+		return -EEXIST;
+
+	/*
+	 * Only attach the power domain to the first device if the
+	 * companion is shared by multiple. This is to prevent doing power
+	 * management twice.
+	 */
+	if (!acpi_device_is_first_physical_node(adev, dev))
+		return -EBUSY;
+
+	acpi_add_pm_notifier(adev, dev, acpi_pm_notify_work_func);
+	dev->pm_domain = &acpi_general_pm_domain;
+	if (power_on) {
+		acpi_dev_pm_full_power(adev);
+		acpi_device_wakeup(adev, ACPI_STATE_S0, false);
+	}
+
+	dev->pm_domain->detach = acpi_dev_pm_detach;
+	return 0;
+}
+EXPORT_SYMBOL_GPL(acpi_dev_pm_attach);
+#endif /* CONFIG_PM */