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-rw-r--r--drivers/acpi/device_pm.c1530
1 files changed, 1530 insertions, 0 deletions
diff --git a/drivers/acpi/device_pm.c b/drivers/acpi/device_pm.c
new file mode 100644
index 0000000000..3b4d048c49
--- /dev/null
+++ b/drivers/acpi/device_pm.c
@@ -0,0 +1,1530 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * drivers/acpi/device_pm.c - ACPI device power management routines.
+ *
+ * Copyright (C) 2012, Intel Corp.
+ * Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ */
+
+#define pr_fmt(fmt) "PM: " fmt
+
+#include <linux/acpi.h>
+#include <linux/export.h>
+#include <linux/mutex.h>
+#include <linux/pm_qos.h>
+#include <linux/pm_domain.h>
+#include <linux/pm_runtime.h>
+#include <linux/suspend.h>
+
+#include "fan.h"
+#include "internal.h"
+
+/**
+ * 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)";
+ }
+}
+
+static int acpi_dev_pm_explicit_get(struct acpi_device *device, int *state)
+{
+ unsigned long long psc;
+ acpi_status status;
+
+ status = acpi_evaluate_integer(device->handle, "_PSC", NULL, &psc);
+ if (ACPI_FAILURE(status))
+ return -ENODEV;
+
+ *state = psc;
+ return 0;
+}
+
+/**
+ * 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).
+ *
+ * Also, it does not update power resource reference counters to ensure that
+ * the power state returned by it will be persistent and it may return a power
+ * state shallower than previously set by acpi_device_set_power() for @device
+ * (if that power state depends on any power resources).
+ */
+int acpi_device_get_power(struct acpi_device *device, int *state)
+{
+ int result = ACPI_STATE_UNKNOWN;
+ struct acpi_device *parent;
+ int error;
+
+ if (!device || !state)
+ return -EINVAL;
+
+ parent = acpi_dev_parent(device);
+
+ if (!device->flags.power_manageable) {
+ /* TBD: Non-recursive algorithm for walking up hierarchy. */
+ *state = parent ? 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) {
+ error = acpi_power_get_inferred_state(device, &result);
+ if (error)
+ return error;
+ }
+ if (device->power.flags.explicit_get) {
+ int psc;
+
+ error = acpi_dev_pm_explicit_get(device, &psc);
+ if (error)
+ return error;
+
+ /*
+ * 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 && parent &&
+ parent->power.state == ACPI_STATE_UNKNOWN &&
+ result == ACPI_STATE_D0)
+ parent->power.state = ACPI_STATE_D0;
+
+ *state = result;
+
+ out:
+ acpi_handle_debug(device->handle, "Power state: %s\n",
+ 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;
+
+ acpi_handle_debug(device->handle, "Power state change: %s -> %s\n",
+ acpi_power_state_string(device->power.state),
+ acpi_power_state_string(state));
+
+ /* Make sure this is a valid target state */
+
+ /* There is a special case for D0 addressed below. */
+ if (state > ACPI_STATE_D0 && state == device->power.state)
+ goto no_change;
+
+ 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 D3cold is not supported, 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) {
+ acpi_handle_debug(device->handle, "Power state %s not supported\n",
+ acpi_power_state_string(state));
+ return -ENODEV;
+ }
+
+ if (!device->power.flags.ignore_parent) {
+ struct acpi_device *parent;
+
+ parent = acpi_dev_parent(device);
+ if (parent && state < parent->power.state) {
+ acpi_handle_debug(device->handle,
+ "Cannot transition to %s for parent in %s\n",
+ acpi_power_state_string(state),
+ acpi_power_state_string(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) {
+ acpi_handle_debug(device->handle,
+ "Cannot transition from %s to %s\n",
+ acpi_power_state_string(device->power.state),
+ acpi_power_state_string(state));
+ return -ENODEV;
+ }
+
+ /*
+ * If the device goes from D3hot to D3cold, _PS3 has been
+ * evaluated for it already, so skip it in that case.
+ */
+ if (device->power.state < ACPI_STATE_D3_HOT) {
+ 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 {
+ int cur_state = device->power.state;
+
+ if (device->power.flags.power_resources) {
+ result = acpi_power_transition(device, ACPI_STATE_D0);
+ if (result)
+ goto end;
+ }
+
+ if (cur_state == ACPI_STATE_D0) {
+ int psc;
+
+ /* Nothing to do here if _PSC is not present. */
+ if (!device->power.flags.explicit_get)
+ goto no_change;
+
+ /*
+ * The power state of the device was set to D0 last
+ * time, but that might have happened before a
+ * system-wide transition involving the platform
+ * firmware, so it may be necessary to evaluate _PS0
+ * for the device here. However, use extra care here
+ * and evaluate _PSC to check the device's current power
+ * state, and only invoke _PS0 if the evaluation of _PSC
+ * is successful and it returns a power state different
+ * from D0.
+ */
+ result = acpi_dev_pm_explicit_get(device, &psc);
+ if (result || psc == ACPI_STATE_D0)
+ goto no_change;
+ }
+
+ result = acpi_dev_pm_explicit_set(device, ACPI_STATE_D0);
+ }
+
+end:
+ if (result) {
+ acpi_handle_debug(device->handle,
+ "Failed to change power state to %s\n",
+ acpi_power_state_string(target_state));
+ } else {
+ device->power.state = target_state;
+ acpi_handle_debug(device->handle, "Power state changed to %s\n",
+ acpi_power_state_string(target_state));
+ }
+
+ return result;
+
+no_change:
+ acpi_handle_debug(device->handle, "Already in %s\n",
+ acpi_power_state_string(state));
+ return 0;
+}
+EXPORT_SYMBOL(acpi_device_set_power);
+
+int acpi_bus_set_power(acpi_handle handle, int state)
+{
+ struct acpi_device *device = acpi_fetch_acpi_dev(handle);
+
+ if (device)
+ return acpi_device_set_power(device, state);
+
+ return -ENODEV;
+}
+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)) {
+ device->flags.initialized = false;
+ 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;
+}
+EXPORT_SYMBOL_GPL(acpi_device_fix_up_power);
+
+static int fix_up_power_if_applicable(struct acpi_device *adev, void *not_used)
+{
+ if (adev->status.present && adev->status.enabled)
+ acpi_device_fix_up_power(adev);
+
+ return 0;
+}
+
+/**
+ * acpi_device_fix_up_power_extended - Force device and its children into D0.
+ * @adev: Parent device object whose power state is to be fixed up.
+ *
+ * Call acpi_device_fix_up_power() for @adev and its children so long as they
+ * are reported as present and enabled.
+ */
+void acpi_device_fix_up_power_extended(struct acpi_device *adev)
+{
+ acpi_device_fix_up_power(adev);
+ acpi_dev_for_each_child(adev, fix_up_power_if_applicable, NULL);
+}
+EXPORT_SYMBOL_GPL(acpi_device_fix_up_power_extended);
+
+/**
+ * acpi_device_fix_up_power_children - Force a device's children into D0.
+ * @adev: Parent device object whose children's power state is to be fixed up.
+ *
+ * Call acpi_device_fix_up_power() for @adev's children so long as they
+ * are reported as present and enabled.
+ */
+void acpi_device_fix_up_power_children(struct acpi_device *adev)
+{
+ acpi_dev_for_each_child(adev, fix_up_power_if_applicable, NULL);
+}
+EXPORT_SYMBOL_GPL(acpi_device_fix_up_power_children);
+
+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 = acpi_fetch_acpi_dev(handle);
+
+ if (device)
+ return acpi_device_update_power(device, state_p);
+
+ return -ENODEV;
+}
+EXPORT_SYMBOL_GPL(acpi_bus_update_power);
+
+bool acpi_bus_power_manageable(acpi_handle handle)
+{
+ struct acpi_device *device = acpi_fetch_acpi_dev(handle);
+
+ return device && device->flags.power_manageable;
+}
+EXPORT_SYMBOL(acpi_bus_power_manageable);
+
+static int acpi_power_up_if_adr_present(struct acpi_device *adev, void *not_used)
+{
+ if (!(adev->flags.power_manageable && adev->pnp.type.bus_address))
+ return 0;
+
+ acpi_handle_debug(adev->handle, "Power state: %s\n",
+ acpi_power_state_string(adev->power.state));
+
+ if (adev->power.state == ACPI_STATE_D3_COLD)
+ return acpi_device_set_power(adev, ACPI_STATE_D0);
+
+ return 0;
+}
+
+/**
+ * acpi_dev_power_up_children_with_adr - Power up childres with valid _ADR
+ * @adev: Parent ACPI device object.
+ *
+ * Change the power states of the direct children of @adev that are in D3cold
+ * and hold valid _ADR objects to D0 in order to allow bus (e.g. PCI)
+ * enumeration code to access them.
+ */
+void acpi_dev_power_up_children_with_adr(struct acpi_device *adev)
+{
+ acpi_dev_for_each_child(adev, acpi_power_up_if_adr_present, NULL);
+}
+
+/**
+ * acpi_dev_power_state_for_wake - Deepest power state for wakeup signaling
+ * @adev: ACPI companion of the target device.
+ *
+ * Evaluate _S0W for @adev and return the value produced by it or return
+ * ACPI_STATE_UNKNOWN on errors (including _S0W not present).
+ */
+u8 acpi_dev_power_state_for_wake(struct acpi_device *adev)
+{
+ unsigned long long state;
+ acpi_status status;
+
+ status = acpi_evaluate_integer(adev->handle, "_S0W", NULL, &state);
+ if (ACPI_FAILURE(status))
+ return ACPI_STATE_UNKNOWN;
+
+ return state;
+}
+
+#ifdef CONFIG_PM
+static DEFINE_MUTEX(acpi_pm_notifier_lock);
+static DEFINE_MUTEX(acpi_pm_notifier_install_lock);
+
+void acpi_pm_wakeup_event(struct device *dev)
+{
+ pm_wakeup_dev_event(dev, 0, acpi_s2idle_wakeup());
+}
+EXPORT_SYMBOL_GPL(acpi_pm_wakeup_event);
+
+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;
+
+ acpi_handle_debug(handle, "Wake notify\n");
+
+ adev = acpi_get_acpi_dev(handle);
+ if (!adev)
+ return;
+
+ mutex_lock(&acpi_pm_notifier_lock);
+
+ if (adev->wakeup.flags.notifier_present) {
+ pm_wakeup_ws_event(adev->wakeup.ws, 0, acpi_s2idle_wakeup());
+ if (adev->wakeup.context.func) {
+ acpi_handle_debug(handle, "Running %pS for %s\n",
+ adev->wakeup.context.func,
+ dev_name(adev->wakeup.context.dev));
+ adev->wakeup.context.func(&adev->wakeup.context);
+ }
+ }
+
+ mutex_unlock(&acpi_pm_notifier_lock);
+
+ acpi_put_acpi_dev(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.
+ * @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 (*func)(struct acpi_device_wakeup_context *context))
+{
+ acpi_status status = AE_ALREADY_EXISTS;
+
+ if (!dev && !func)
+ return AE_BAD_PARAMETER;
+
+ mutex_lock(&acpi_pm_notifier_install_lock);
+
+ if (adev->wakeup.flags.notifier_present)
+ goto out;
+
+ status = acpi_install_notify_handler(adev->handle, ACPI_SYSTEM_NOTIFY,
+ acpi_pm_notify_handler, NULL);
+ if (ACPI_FAILURE(status))
+ goto out;
+
+ mutex_lock(&acpi_pm_notifier_lock);
+ adev->wakeup.ws = wakeup_source_register(&adev->dev,
+ dev_name(&adev->dev));
+ adev->wakeup.context.dev = dev;
+ adev->wakeup.context.func = func;
+ adev->wakeup.flags.notifier_present = true;
+ mutex_unlock(&acpi_pm_notifier_lock);
+
+ out:
+ mutex_unlock(&acpi_pm_notifier_install_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_install_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;
+
+ mutex_lock(&acpi_pm_notifier_lock);
+ adev->wakeup.context.func = NULL;
+ adev->wakeup.context.dev = NULL;
+ wakeup_source_unregister(adev->wakeup.ws);
+ adev->wakeup.flags.notifier_present = false;
+ mutex_unlock(&acpi_pm_notifier_lock);
+
+ out:
+ mutex_unlock(&acpi_pm_notifier_install_lock);
+ return status;
+}
+
+bool acpi_bus_can_wakeup(acpi_handle handle)
+{
+ struct acpi_device *device = acpi_fetch_acpi_dev(handle);
+
+ return device && device->wakeup.flags.valid;
+}
+EXPORT_SYMBOL(acpi_bus_can_wakeup);
+
+bool acpi_pm_device_can_wakeup(struct device *dev)
+{
+ struct acpi_device *adev = ACPI_COMPANION(dev);
+
+ return adev ? acpi_device_can_wakeup(adev) : false;
+}
+
+/**
+ * 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;
+ bool has_sxd = 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;
+ }
+
+ if (status == AE_OK)
+ has_sxd = true;
+
+ d_min = ret;
+ wakeup = device_may_wakeup(dev) && adev->wakeup.flags.valid
+ && adev->wakeup.sleep_state >= target_state;
+ } else if (device_may_wakeup(dev) && dev->power.wakeirq) {
+ /*
+ * The ACPI subsystem doesn't manage the wake bit for IRQs
+ * defined with ExclusiveAndWake and SharedAndWake. Instead we
+ * expect them to be managed via the PM subsystem. Drivers
+ * should call dev_pm_set_wake_irq to register an IRQ as a wake
+ * source.
+ *
+ * If a device has a wake IRQ attached we need to check the
+ * _S0W method to get the correct wake D-state. Otherwise we
+ * end up putting the device into D3Cold which will more than
+ * likely disable wake functionality.
+ */
+ wakeup = true;
+ } else {
+ /* ACPI GPE is specified in _PRW. */
+ 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) {
+ /* No _SxW. In this case, the ACPI spec says that we
+ * must not go into any power state deeper than the
+ * value returned from _SxD.
+ */
+ if (has_sxd && 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.
+ * @context: Device wakeup context.
+ */
+static void acpi_pm_notify_work_func(struct acpi_device_wakeup_context *context)
+{
+ struct device *dev = context->dev;
+
+ if (dev) {
+ pm_wakeup_event(dev, 0);
+ pm_request_resume(dev);
+ }
+}
+
+static DEFINE_MUTEX(acpi_wakeup_lock);
+
+static int __acpi_device_wakeup_enable(struct acpi_device *adev,
+ u32 target_state)
+{
+ struct acpi_device_wakeup *wakeup = &adev->wakeup;
+ acpi_status status;
+ int error = 0;
+
+ mutex_lock(&acpi_wakeup_lock);
+
+ /*
+ * If the device wakeup power is already enabled, disable it and enable
+ * it again in case it depends on the configuration of subordinate
+ * devices and the conditions have changed since it was enabled last
+ * time.
+ */
+ if (wakeup->enable_count > 0)
+ acpi_disable_wakeup_device_power(adev);
+
+ error = acpi_enable_wakeup_device_power(adev, target_state);
+ if (error) {
+ if (wakeup->enable_count > 0) {
+ acpi_disable_gpe(wakeup->gpe_device, wakeup->gpe_number);
+ wakeup->enable_count = 0;
+ }
+ goto out;
+ }
+
+ if (wakeup->enable_count > 0)
+ goto inc;
+
+ status = acpi_enable_gpe(wakeup->gpe_device, wakeup->gpe_number);
+ if (ACPI_FAILURE(status)) {
+ acpi_disable_wakeup_device_power(adev);
+ error = -EIO;
+ goto out;
+ }
+
+ acpi_handle_debug(adev->handle, "GPE%2X enabled for wakeup\n",
+ (unsigned int)wakeup->gpe_number);
+
+inc:
+ if (wakeup->enable_count < INT_MAX)
+ wakeup->enable_count++;
+ else
+ acpi_handle_info(adev->handle, "Wakeup enable count out of bounds!\n");
+
+out:
+ mutex_unlock(&acpi_wakeup_lock);
+ return error;
+}
+
+/**
+ * acpi_device_wakeup_enable - Enable wakeup functionality for device.
+ * @adev: ACPI device to enable wakeup functionality for.
+ * @target_state: State the system is transitioning into.
+ *
+ * Enable the GPE associated with @adev so that it can generate wakeup signals
+ * for the device in response to external (remote) events and enable wakeup
+ * power for it.
+ *
+ * Callers must ensure that @adev is a valid ACPI device node before executing
+ * this function.
+ */
+static int acpi_device_wakeup_enable(struct acpi_device *adev, u32 target_state)
+{
+ return __acpi_device_wakeup_enable(adev, target_state);
+}
+
+/**
+ * acpi_device_wakeup_disable - Disable wakeup functionality for device.
+ * @adev: ACPI device to disable wakeup functionality for.
+ *
+ * Disable the GPE associated with @adev and disable wakeup power for it.
+ *
+ * Callers must ensure that @adev is a valid ACPI device node before executing
+ * this function.
+ */
+static void acpi_device_wakeup_disable(struct acpi_device *adev)
+{
+ struct acpi_device_wakeup *wakeup = &adev->wakeup;
+
+ mutex_lock(&acpi_wakeup_lock);
+
+ if (!wakeup->enable_count)
+ goto out;
+
+ acpi_disable_gpe(wakeup->gpe_device, wakeup->gpe_number);
+ acpi_disable_wakeup_device_power(adev);
+
+ wakeup->enable_count--;
+
+out:
+ mutex_unlock(&acpi_wakeup_lock);
+}
+
+/**
+ * acpi_pm_set_device_wakeup - Enable/disable remote wakeup for given device.
+ * @dev: Device to enable/disable to generate wakeup events.
+ * @enable: Whether to enable or disable the wakeup functionality.
+ */
+int acpi_pm_set_device_wakeup(struct device *dev, bool enable)
+{
+ struct acpi_device *adev;
+ int error;
+
+ adev = ACPI_COMPANION(dev);
+ if (!adev) {
+ dev_dbg(dev, "ACPI companion missing in %s!\n", __func__);
+ return -ENODEV;
+ }
+
+ if (!acpi_device_can_wakeup(adev))
+ return -EINVAL;
+
+ if (!enable) {
+ acpi_device_wakeup_disable(adev);
+ dev_dbg(dev, "Wakeup disabled by ACPI\n");
+ return 0;
+ }
+
+ error = __acpi_device_wakeup_enable(adev, acpi_target_system_state());
+ if (!error)
+ dev_dbg(dev, "Wakeup enabled by ACPI\n");
+
+ return error;
+}
+EXPORT_SYMBOL_GPL(acpi_pm_set_device_wakeup);
+
+/**
+ * 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_suspend - Put device into a low-power state using ACPI.
+ * @dev: Device to put into a low-power state.
+ * @wakeup: Whether or not to enable wakeup for the device.
+ *
+ * Put the given device into a 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_suspend(struct device *dev, bool wakeup)
+{
+ struct acpi_device *adev = ACPI_COMPANION(dev);
+ u32 target_state = acpi_target_system_state();
+ int error;
+
+ if (!adev)
+ return 0;
+
+ if (wakeup && acpi_device_can_wakeup(adev)) {
+ error = acpi_device_wakeup_enable(adev, target_state);
+ if (error)
+ return -EAGAIN;
+ } else {
+ wakeup = false;
+ }
+
+ error = acpi_dev_pm_low_power(dev, adev, target_state);
+ if (error && wakeup)
+ acpi_device_wakeup_disable(adev);
+
+ return error;
+}
+EXPORT_SYMBOL_GPL(acpi_dev_suspend);
+
+/**
+ * acpi_dev_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. Set the power state of the device to ACPI D0 and disable wakeup.
+ */
+int acpi_dev_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_disable(adev);
+ return error;
+}
+EXPORT_SYMBOL_GPL(acpi_dev_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_suspend(dev, true);
+}
+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_resume(dev);
+
+ return ret ? ret : pm_generic_runtime_resume(dev);
+}
+EXPORT_SYMBOL_GPL(acpi_subsys_runtime_resume);
+
+#ifdef CONFIG_PM_SLEEP
+static bool acpi_dev_needs_resume(struct device *dev, struct acpi_device *adev)
+{
+ u32 sys_target = acpi_target_system_state();
+ int ret, state;
+
+ if (!pm_runtime_suspended(dev) || !adev || (adev->wakeup.flags.valid &&
+ device_may_wakeup(dev) != !!adev->wakeup.prepare_count))
+ return true;
+
+ if (sys_target == ACPI_STATE_S0)
+ return false;
+
+ if (adev->power.flags.dsw_present)
+ return true;
+
+ ret = acpi_dev_pm_get_state(dev, adev, sys_target, NULL, &state);
+ if (ret)
+ return true;
+
+ return state != adev->power.state;
+}
+
+/**
+ * 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);
+
+ if (dev->driver && dev->driver->pm && dev->driver->pm->prepare) {
+ int ret = dev->driver->pm->prepare(dev);
+
+ if (ret < 0)
+ return ret;
+
+ if (!ret && dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_PREPARE))
+ return 0;
+ }
+
+ return !acpi_dev_needs_resume(dev, adev);
+}
+EXPORT_SYMBOL_GPL(acpi_subsys_prepare);
+
+/**
+ * acpi_subsys_complete - Finalize device's resume during system resume.
+ * @dev: Device to handle.
+ */
+void acpi_subsys_complete(struct device *dev)
+{
+ pm_generic_complete(dev);
+ /*
+ * If the device had been runtime-suspended before the system went into
+ * the sleep state it is going out of and it has never been resumed till
+ * now, resume it in case the firmware powered it up.
+ */
+ if (pm_runtime_suspended(dev) && pm_resume_via_firmware())
+ pm_request_resume(dev);
+}
+EXPORT_SYMBOL_GPL(acpi_subsys_complete);
+
+/**
+ * acpi_subsys_suspend - Run the device driver's suspend callback.
+ * @dev: Device to handle.
+ *
+ * Follow PCI and resume devices from runtime suspend before running their
+ * system suspend callbacks, unless the driver can cope with runtime-suspended
+ * devices during system suspend and there are no ACPI-specific reasons for
+ * resuming them.
+ */
+int acpi_subsys_suspend(struct device *dev)
+{
+ if (!dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND) ||
+ acpi_dev_needs_resume(dev, ACPI_COMPANION(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;
+
+ if (dev_pm_skip_suspend(dev))
+ return 0;
+
+ ret = pm_generic_suspend_late(dev);
+ return ret ? ret : acpi_dev_suspend(dev, device_may_wakeup(dev));
+}
+EXPORT_SYMBOL_GPL(acpi_subsys_suspend_late);
+
+/**
+ * acpi_subsys_suspend_noirq - Run the device driver's "noirq" suspend callback.
+ * @dev: Device to suspend.
+ */
+int acpi_subsys_suspend_noirq(struct device *dev)
+{
+ int ret;
+
+ if (dev_pm_skip_suspend(dev))
+ return 0;
+
+ ret = pm_generic_suspend_noirq(dev);
+ if (ret)
+ return ret;
+
+ /*
+ * If the target system sleep state is suspend-to-idle, it is sufficient
+ * to check whether or not the device's wakeup settings are good for
+ * runtime PM. Otherwise, the pm_resume_via_firmware() check will cause
+ * acpi_subsys_complete() to take care of fixing up the device's state
+ * anyway, if need be.
+ */
+ if (device_can_wakeup(dev) && !device_may_wakeup(dev))
+ dev->power.may_skip_resume = false;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(acpi_subsys_suspend_noirq);
+
+/**
+ * acpi_subsys_resume_noirq - Run the device driver's "noirq" resume callback.
+ * @dev: Device to handle.
+ */
+static int acpi_subsys_resume_noirq(struct device *dev)
+{
+ if (dev_pm_skip_resume(dev))
+ return 0;
+
+ return pm_generic_resume_noirq(dev);
+}
+
+/**
+ * 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, but only do that if device either defines early resume
+ * handler, or does not define power operations at all. Otherwise powering up
+ * of the device is postponed to the normal resume phase.
+ */
+static int acpi_subsys_resume_early(struct device *dev)
+{
+ const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
+ int ret;
+
+ if (dev_pm_skip_resume(dev))
+ return 0;
+
+ if (pm && !pm->resume_early) {
+ dev_dbg(dev, "postponing D0 transition to normal resume stage\n");
+ return 0;
+ }
+
+ ret = acpi_dev_resume(dev);
+ return ret ? ret : pm_generic_resume_early(dev);
+}
+
+/**
+ * acpi_subsys_resume - Resume device using ACPI.
+ * @dev: Device to Resume.
+ *
+ * Use ACPI to put the given device into the full-power state if it has not been
+ * powered up during early resume phase, and carry out the generic resume
+ * procedure for it during system transition into the working state.
+ */
+static int acpi_subsys_resume(struct device *dev)
+{
+ const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
+ int ret = 0;
+
+ if (!dev_pm_skip_resume(dev) && pm && !pm->resume_early) {
+ dev_dbg(dev, "executing postponed D0 transition\n");
+ ret = acpi_dev_resume(dev);
+ }
+
+ return ret ? ret : pm_generic_resume(dev);
+}
+
+/**
+ * acpi_subsys_freeze - Run the device driver's freeze callback.
+ * @dev: Device to handle.
+ */
+int acpi_subsys_freeze(struct device *dev)
+{
+ /*
+ * Resume all runtime-suspended devices before creating a snapshot
+ * image of system memory, because the restore kernel generally cannot
+ * be expected to always handle them consistently and they need to be
+ * put into the runtime-active metastate during system resume anyway,
+ * so it is better to ensure that the state saved in the image will be
+ * always consistent with that.
+ */
+ pm_runtime_resume(dev);
+
+ return pm_generic_freeze(dev);
+}
+EXPORT_SYMBOL_GPL(acpi_subsys_freeze);
+
+/**
+ * acpi_subsys_restore_early - Restore device using ACPI.
+ * @dev: Device to restore.
+ */
+int acpi_subsys_restore_early(struct device *dev)
+{
+ int ret = acpi_dev_resume(dev);
+
+ return ret ? ret : pm_generic_restore_early(dev);
+}
+EXPORT_SYMBOL_GPL(acpi_subsys_restore_early);
+
+/**
+ * acpi_subsys_poweroff - Run the device driver's poweroff callback.
+ * @dev: Device to handle.
+ *
+ * Follow PCI and resume devices from runtime suspend before running their
+ * system poweroff callbacks, unless the driver can cope with runtime-suspended
+ * devices during system suspend and there are no ACPI-specific reasons for
+ * resuming them.
+ */
+int acpi_subsys_poweroff(struct device *dev)
+{
+ if (!dev_pm_test_driver_flags(dev, DPM_FLAG_SMART_SUSPEND) ||
+ acpi_dev_needs_resume(dev, ACPI_COMPANION(dev)))
+ pm_runtime_resume(dev);
+
+ return pm_generic_poweroff(dev);
+}
+EXPORT_SYMBOL_GPL(acpi_subsys_poweroff);
+
+/**
+ * acpi_subsys_poweroff_late - Run the device driver's poweroff callback.
+ * @dev: Device to handle.
+ *
+ * Carry out the generic late poweroff procedure for @dev and use ACPI to put
+ * it into a low-power state during system transition into a sleep state.
+ */
+static int acpi_subsys_poweroff_late(struct device *dev)
+{
+ int ret;
+
+ if (dev_pm_skip_suspend(dev))
+ return 0;
+
+ ret = pm_generic_poweroff_late(dev);
+ if (ret)
+ return ret;
+
+ return acpi_dev_suspend(dev, device_may_wakeup(dev));
+}
+
+/**
+ * acpi_subsys_poweroff_noirq - Run the driver's "noirq" poweroff callback.
+ * @dev: Device to suspend.
+ */
+static int acpi_subsys_poweroff_noirq(struct device *dev)
+{
+ if (dev_pm_skip_suspend(dev))
+ return 0;
+
+ return pm_generic_poweroff_noirq(dev);
+}
+#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 = acpi_subsys_complete,
+ .suspend = acpi_subsys_suspend,
+ .resume = acpi_subsys_resume,
+ .suspend_late = acpi_subsys_suspend_late,
+ .suspend_noirq = acpi_subsys_suspend_noirq,
+ .resume_noirq = acpi_subsys_resume_noirq,
+ .resume_early = acpi_subsys_resume_early,
+ .freeze = acpi_subsys_freeze,
+ .poweroff = acpi_subsys_poweroff,
+ .poweroff_late = acpi_subsys_poweroff_late,
+ .poweroff_noirq = acpi_subsys_poweroff_noirq,
+ .restore_early = acpi_subsys_restore_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_set(dev, 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_disable(adev);
+ 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)
+{
+ /*
+ * Skip devices whose ACPI companions match the device IDs below,
+ * because they require special power management handling incompatible
+ * with the generic ACPI PM domain.
+ */
+ static const struct acpi_device_id special_pm_ids[] = {
+ ACPI_FAN_DEVICE_IDS,
+ {}
+ };
+ struct acpi_device *adev = ACPI_COMPANION(dev);
+
+ if (!adev || !acpi_match_device_ids(adev, special_pm_ids))
+ return 0;
+
+ /*
+ * 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 0;
+
+ acpi_add_pm_notifier(adev, dev, acpi_pm_notify_work_func);
+ dev_pm_domain_set(dev, &acpi_general_pm_domain);
+ if (power_on) {
+ acpi_dev_pm_full_power(adev);
+ acpi_device_wakeup_disable(adev);
+ }
+
+ dev->pm_domain->detach = acpi_dev_pm_detach;
+ return 1;
+}
+EXPORT_SYMBOL_GPL(acpi_dev_pm_attach);
+
+/**
+ * acpi_storage_d3 - Check if D3 should be used in the suspend path
+ * @dev: Device to check
+ *
+ * Return %true if the platform firmware wants @dev to be programmed
+ * into D3hot or D3cold (if supported) in the suspend path, or %false
+ * when there is no specific preference. On some platforms, if this
+ * hint is ignored, @dev may remain unresponsive after suspending the
+ * platform as a whole.
+ *
+ * Although the property has storage in the name it actually is
+ * applied to the PCIe slot and plugging in a non-storage device the
+ * same platform restrictions will likely apply.
+ */
+bool acpi_storage_d3(struct device *dev)
+{
+ struct acpi_device *adev = ACPI_COMPANION(dev);
+ u8 val;
+
+ if (force_storage_d3())
+ return true;
+
+ if (!adev)
+ return false;
+ if (fwnode_property_read_u8(acpi_fwnode_handle(adev), "StorageD3Enable",
+ &val))
+ return false;
+ return val == 1;
+}
+EXPORT_SYMBOL_GPL(acpi_storage_d3);
+
+/**
+ * acpi_dev_state_d0 - Tell if the device is in D0 power state
+ * @dev: Physical device the ACPI power state of which to check
+ *
+ * On a system without ACPI, return true. On a system with ACPI, return true if
+ * the current ACPI power state of the device is D0, or false otherwise.
+ *
+ * Note that the power state of a device is not well-defined after it has been
+ * passed to acpi_device_set_power() and before that function returns, so it is
+ * not valid to ask for the ACPI power state of the device in that time frame.
+ *
+ * This function is intended to be used in a driver's probe or remove
+ * function. See Documentation/firmware-guide/acpi/non-d0-probe.rst for
+ * more information.
+ */
+bool acpi_dev_state_d0(struct device *dev)
+{
+ struct acpi_device *adev = ACPI_COMPANION(dev);
+
+ if (!adev)
+ return true;
+
+ return adev->power.state == ACPI_STATE_D0;
+}
+EXPORT_SYMBOL_GPL(acpi_dev_state_d0);
+
+#endif /* CONFIG_PM */