===================================================================
@@ -35,6 +35,10 @@ int pci_probe_reset_function(struct pci_
*
* @sleep_wake: enables/disables the system wake up capability of given device
*
+ * @run_wake: enables/disables the platform to generate run-time wake-up events
+ * for given device (the device's wake-up capability has to be
+ * enabled by @sleep_wake for this feature to work)
+ *
* If given platform is generally capable of power managing PCI devices, all of
* these callbacks are mandatory.
*/
@@ -44,12 +48,15 @@ struct pci_platform_pm_ops {
pci_power_t (*choose_state)(struct pci_dev *dev);
bool (*can_wakeup)(struct pci_dev *dev);
int (*sleep_wake)(struct pci_dev *dev, bool enable);
+ int (*run_wake)(struct pci_dev *dev, bool enable);
};
extern int pci_set_platform_pm(struct pci_platform_pm_ops *ops);
extern void pci_update_current_state(struct pci_dev *dev, pci_power_t state);
extern void pci_disable_enabled_device(struct pci_dev *dev);
extern bool pci_check_pme_status(struct pci_dev *dev);
+extern int __pci_pme_wakeup(struct pci_dev *dev, void *ign);
+extern void pci_pme_wakeup_bus(struct pci_bus *bus);
extern void pci_pm_init(struct pci_dev *dev);
extern void platform_pci_wakeup_init(struct pci_dev *dev);
extern void pci_allocate_cap_save_buffers(struct pci_dev *dev);
===================================================================
@@ -16,8 +16,276 @@
#include <acpi/acpi_bus.h>
#include <linux/pci-acpi.h>
+#include <linux/pm_runtime.h>
#include "pci.h"
+static DEFINE_MUTEX(pci_acpi_notifier_mtx);
+
+struct pci_acpi_notify_data
+{
+ acpi_notify_handler hp_cb;
+ void *hp_data;
+ struct pci_bus *pci_bus;
+ struct pci_dev *pci_dev;
+};
+
+/**
+ * pci_acpi_event_fn - Universal system notification handler.
+ * @handle: ACPI handle of a device the notification is for.
+ * @event: Type of the signaled event.
+ * @ign: The value of this argument is ignored.
+ *
+ * Use @handle to obtain the address of the ACPI device object the event is
+ * signaled for. If this is a wake-up event, execute the appropriate PME
+ * handler for the bus or device represented by it (or both, if @dev is a
+ * bridge). If this is not a wake-up event, execute the hotplug notify handler
+ * for @handle.
+ */
+static void pci_acpi_event_fn(acpi_handle handle, u32 event, void *ign)
+{
+ struct acpi_device *dev;
+ struct pci_acpi_notify_data *nd;
+
+ if (ACPI_FAILURE(acpi_bus_get_device(handle, &dev))) {
+ pr_warning("ACPI handle has no context in %s!\n", __func__);
+ return;
+ }
+
+ mutex_lock(&pci_acpi_notifier_mtx);
+
+ nd = dev->bus_data;
+ if (!nd)
+ goto out;
+
+ if (event == ACPI_NOTIFY_DEVICE_WAKE) {
+ if (nd->pci_bus) {
+ pci_pme_wakeup_bus(nd->pci_bus);
+ }
+ if (nd->pci_dev) {
+ pci_check_pme_status(nd->pci_dev);
+ pm_request_resume(&nd->pci_dev->dev);
+ }
+ } else if (nd->hp_cb) {
+ nd->hp_cb(handle, event, nd->hp_data);
+ }
+
+ out:
+ mutex_unlock(&pci_acpi_notifier_mtx);
+}
+
+/**
+ * add_notify_data - Create a new notify data object for given ACPI device.
+ * @dev: Device to create the notify data object for.
+ */
+static struct pci_acpi_notify_data *add_notify_data(struct acpi_device *dev)
+{
+ struct pci_acpi_notify_data *nd;
+
+ nd = kzalloc(sizeof(*nd), GFP_KERNEL);
+ if (!nd)
+ return NULL;
+
+ dev->bus_data = nd;
+ return nd;
+}
+
+/**
+ * remove_notify_data - Remove the notify data object from given ACPI device.
+ * @dev: Device to remove the notify data object from.
+ */
+static void remove_notify_data(struct acpi_device *dev)
+{
+ kfree(dev->bus_data);
+ dev->bus_data = NULL;
+}
+
+/**
+ * pci_acpi_add_hp_notifier - Register a hotplug notifier for given device.
+ * @handle: ACPI handle of the device to register the notifier for.
+ * @handler: Callback to execute for hotplug events related to @handle.
+ * @context: Pointer to the context data to pass to @handler.
+ *
+ * Use @handle to get an ACPI device object and check if there is a notify data
+ * object for it. If this is the case, add @handler and @context to the
+ * existing notify data object, unless there already is a hotplug handler in
+ * there. Otherwise, create a new notify data object for the ACPI device
+ * associated with @handle and add @handler and @context to it.
+ */
+acpi_status pci_acpi_add_hp_notifier(acpi_handle handle,
+ acpi_notify_handler handler, void *context)
+{
+ struct pci_acpi_notify_data *nd;
+ struct acpi_device *dev;
+ acpi_status status = AE_OK;
+
+ if (!handle || ACPI_FAILURE(acpi_bus_get_device(handle, &dev)))
+ return AE_NOT_FOUND;
+
+ mutex_lock(&pci_acpi_notifier_mtx);
+
+ nd = dev->bus_data;
+ if (nd) {
+ if (!nd->hp_cb)
+ goto add;
+
+ status = AE_ALREADY_EXISTS;
+ goto out;
+ }
+
+ nd = add_notify_data(dev);
+ if (!nd) {
+ status = AE_NO_MEMORY;
+ goto out;
+ }
+
+ status = acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
+ pci_acpi_event_fn, NULL);
+ if (ACPI_FAILURE(status)) {
+ remove_notify_data(dev);
+ goto out;
+ }
+
+ add:
+ nd->hp_cb = handler;
+ nd->hp_data = context;
+
+ out:
+ mutex_unlock(&pci_acpi_notifier_mtx);
+
+ return status;
+}
+EXPORT_SYMBOL_GPL(pci_acpi_add_hp_notifier);
+
+/**
+ * pci_acpi_remove_hp_notifier - Unregister a hotplug notifier for given device.
+ * @handle: ACPI handle of the device to unregister the notifier for.
+ * @handler: Callback executed for hotplug events related to @handle.
+ *
+ * Remove the hotplug callback and the pointer to the hotplug context data from
+ * the notify data object belonging to the device represented by @handle. If
+ * the notify data object is not necessary any more, remove it altogether.
+ */
+acpi_status pci_acpi_remove_hp_notifier(acpi_handle handle,
+ acpi_notify_handler handler)
+{
+ struct pci_acpi_notify_data *nd;
+ struct acpi_device *dev;
+ acpi_status status = AE_NOT_FOUND;
+
+ if (!handle || ACPI_FAILURE(acpi_bus_get_device(handle, &dev)))
+ return AE_NOT_FOUND;
+
+ mutex_lock(&pci_acpi_notifier_mtx);
+
+ nd = dev->bus_data;
+ if (!nd)
+ goto out;
+
+ nd->hp_data = NULL;
+ nd->hp_cb = NULL;
+
+ if (nd->pci_bus || nd->pci_dev)
+ goto out;
+
+ status = acpi_remove_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
+ pci_acpi_event_fn);
+ remove_notify_data(dev);
+
+ out:
+ mutex_unlock(&pci_acpi_notifier_mtx);
+ return status;
+}
+EXPORT_SYMBOL_GPL(pci_acpi_remove_hp_notifier);
+
+/**
+ * pci_acpi_add_pm_notifier - Register PM notifier for given device.
+ * @dev: ACPI device to add the notifier for.
+ * @pci_dev: PCI device to check for the PME status if an event is signaled.
+ * @pci_bus: PCI bus to walk (checking PME status) if an event is signaled.
+ *
+ * Check if there is a notify data object for @dev and if that is the case, add
+ * @pci_dev to it as the device whose PME status should be checked whenever a PM
+ * event is signaled for @dev. Also, add @pci_bus to it as the bus to walk
+ * checking the PME status of all devices on it whenever a PM event is signaled
+ * for @dev.
+ *
+ * Otherwise, create a new notify data object for @dev and add both @pci_dev and
+ * @pci_bus to it.
+ *
+ * NOTE: @dev need not be a run-wake or wake-up device to be a valid source of
+ * PM wake-up events. For example, wake-up events may be generated for bridges
+ * if one of the devices below the bridge is signaling PME, even if the bridge
+ * itself doesn't have a wake-up GPE associated with it.
+ */
+acpi_status pci_acpi_add_pm_notifier(struct acpi_device *dev,
+ struct pci_dev *pci_dev,
+ struct pci_bus *pci_bus)
+{
+ struct pci_acpi_notify_data *nd;
+ acpi_status status = AE_OK;
+
+ mutex_lock(&pci_acpi_notifier_mtx);
+
+ nd = dev->bus_data;
+ if (nd)
+ goto add;
+
+ nd = add_notify_data(dev);
+ if (!nd) {
+ status = AE_NO_MEMORY;
+ goto out;
+ }
+
+ status = acpi_install_notify_handler(dev->handle, ACPI_SYSTEM_NOTIFY,
+ pci_acpi_event_fn, NULL);
+ if (ACPI_FAILURE(status)) {
+ remove_notify_data(dev);
+ goto out;
+ }
+
+ add:
+ nd->pci_dev = pci_dev;
+ nd->pci_bus = pci_bus;
+
+ out:
+ mutex_unlock(&pci_acpi_notifier_mtx);
+ return status;
+}
+
+/**
+ * pci_acpi_remove_pm_notifier - Unregister PM notifier for given device.
+ * @dev: ACPI device to remove the notifier from.
+ *
+ * Find the notify data object for @dev and clear its @pci_dev and @pci_bus
+ * fields. If the notify data object is not necessary any more after that,
+ * remove it too.
+ */
+acpi_status pci_acpi_remove_pm_notifier(struct acpi_device *dev)
+{
+ struct pci_acpi_notify_data *nd;
+ acpi_status status = AE_NOT_FOUND;
+
+ mutex_lock(&pci_acpi_notifier_mtx);
+
+ nd = dev->bus_data;
+ if (!nd)
+ goto out;
+
+ nd->pci_dev = NULL;
+ nd->pci_bus = NULL;
+
+ if (nd->hp_cb)
+ goto out;
+
+ status = acpi_remove_notify_handler(dev->handle, ACPI_SYSTEM_NOTIFY,
+ pci_acpi_event_fn);
+ remove_notify_data(dev);
+
+ out:
+ mutex_unlock(&pci_acpi_notifier_mtx);
+ return status;
+}
+
/*
* _SxD returns the D-state with the highest power
* (lowest D-state number) supported in the S-state "x".
@@ -131,12 +399,85 @@ static int acpi_pci_sleep_wake(struct pc
return 0;
}
+/**
+ * acpi_dev_run_wake - Enable/disable wake-up for given device.
+ * @phys_dev: Device to enable/disable the platform to wake-up the system for.
+ * @enable: Whether enable or disable the wake-up functionality.
+ *
+ * Find the ACPI device object corresponding to @pci_dev and try to
+ * enable/disable the GPE associated with it.
+ */
+static int acpi_dev_run_wake(struct device *phys_dev, bool enable)
+{
+ struct acpi_device *dev;
+ acpi_handle handle;
+ int error = -ENODEV;
+
+ if (!device_run_wake(phys_dev))
+ return -EINVAL;
+
+ handle = DEVICE_ACPI_HANDLE(phys_dev);
+ if (!handle || ACPI_FAILURE(acpi_bus_get_device(handle, &dev))) {
+ dev_dbg(phys_dev, "ACPI handle has no context in %s!\n",
+ __func__);
+ return -ENODEV;
+ }
+
+ if (enable) {
+ if (!dev->wakeup.run_wake_count++) {
+ acpi_enable_wakeup_device_power(dev, ACPI_STATE_S0);
+ acpi_ref_runtime_gpe(dev->wakeup.gpe_device,
+ dev->wakeup.gpe_number);
+ }
+ } else if (dev->wakeup.run_wake_count > 0) {
+ if (!--dev->wakeup.run_wake_count) {
+ acpi_unref_runtime_gpe(dev->wakeup.gpe_device,
+ dev->wakeup.gpe_number);
+ acpi_disable_wakeup_device_power(dev);
+ }
+ } else {
+ error = -EALREADY;
+ }
+
+ return error;
+}
+
+static void acpi_pci_propagate_run_wake(struct pci_bus *bus, bool enable)
+{
+ while (bus->parent) {
+ struct pci_dev *bridge = bus->self;
+
+ if (bridge->pme_interrupt)
+ return;
+ if (!acpi_dev_run_wake(&bridge->dev, enable))
+ return;
+ bus = bus->parent;
+ }
+
+ /* We have reached the root bus. */
+ if (bus->bridge)
+ acpi_dev_run_wake(bus->bridge, enable);
+}
+
+static int acpi_pci_run_wake(struct pci_dev *dev, bool enable)
+{
+ if (dev->pme_interrupt)
+ return 0;
+
+ if (!acpi_dev_run_wake(&dev->dev, enable))
+ return 0;
+
+ acpi_pci_propagate_run_wake(dev->bus, enable);
+ return 0;
+}
+
static struct pci_platform_pm_ops acpi_pci_platform_pm = {
.is_manageable = acpi_pci_power_manageable,
.set_state = acpi_pci_set_power_state,
.choose_state = acpi_pci_choose_state,
.can_wakeup = acpi_pci_can_wakeup,
.sleep_wake = acpi_pci_sleep_wake,
+ .run_wake = acpi_pci_run_wake,
};
/* ACPI bus type */
===================================================================
@@ -20,6 +20,7 @@
#include <linux/pm_wakeup.h>
#include <linux/interrupt.h>
#include <linux/device.h>
+#include <linux/pm_runtime.h>
#include <asm/setup.h>
#include "pci.h"
@@ -462,6 +463,12 @@ static inline int platform_pci_sleep_wak
pci_platform_pm->sleep_wake(dev, enable) : -ENODEV;
}
+static inline int platform_pci_run_wake(struct pci_dev *dev, bool enable)
+{
+ return pci_platform_pm ?
+ pci_platform_pm->run_wake(dev, enable) : -ENODEV;
+}
+
/**
* pci_raw_set_power_state - Use PCI PM registers to set the power state of
* given PCI device
@@ -1230,6 +1237,31 @@ bool pci_check_pme_status(struct pci_dev
}
/**
+ * pci_pme_wakeup - Wake up a PCI device if its PME Status bit is set.
+ * @dev: Device to handle.
+ * @ign: Ignored.
+ *
+ * Check if @dev has generated PME and queue a resume request for it in that
+ * case.
+ */
+static int pci_pme_wakeup(struct pci_dev *dev, void *ign)
+{
+ if (pci_check_pme_status(dev))
+ pm_request_resume(&dev->dev);
+ return 0;
+}
+
+/**
+ * pci_pme_wakeup_bus - Walk given bus and wake up devices on it, if necessary.
+ * @bus: Top bus of the subtree to walk.
+ */
+void pci_pme_wakeup_bus(struct pci_bus *bus)
+{
+ if (bus)
+ pci_walk_bus(bus, pci_pme_wakeup, NULL);
+}
+
+/**
* pci_pme_capable - check the capability of PCI device to generate PME#
* @dev: PCI device to handle.
* @state: PCI state from which device will issue PME#.
@@ -1434,6 +1466,41 @@ int pci_back_from_sleep(struct pci_dev *
}
/**
+ * pci_dev_run_wake - Check if device can generate run-time wake-up events.
+ * @dev: Device to check.
+ *
+ * Return true if the device itself is cabable of generating wake-up events
+ * (through the platform or using the native PCIe PME) or if the device supports
+ * PME and one of its upstream bridges can generate wake-up events.
+ */
+bool pci_dev_run_wake(struct pci_dev *dev)
+{
+ struct pci_bus *bus = dev->bus;
+
+ if (device_run_wake(&dev->dev))
+ return true;
+
+ if (!dev->pme_support)
+ return false;
+
+ while (bus->parent) {
+ struct pci_dev *bridge = bus->self;
+
+ if (device_run_wake(&bridge->dev))
+ return true;
+
+ bus = bus->parent;
+ }
+
+ /* We have reached the root bus. */
+ if (bus->bridge)
+ return device_run_wake(bus->bridge);
+
+ return false;
+}
+EXPORT_SYMBOL_GPL(pci_dev_run_wake);
+
+/**
* pci_pm_init - Initialize PM functions of given PCI device
* @dev: PCI device to handle.
*/
===================================================================
@@ -11,6 +11,16 @@
#include <linux/acpi.h>
#ifdef CONFIG_ACPI
+extern acpi_status pci_acpi_add_hp_notifier(acpi_handle handle,
+ acpi_notify_handler handler,
+ void *context);
+extern acpi_status pci_acpi_remove_hp_notifier(acpi_handle handle,
+ acpi_notify_handler handler);
+extern acpi_status pci_acpi_add_pm_notifier(struct acpi_device *dev,
+ struct pci_dev *pci_dev,
+ struct pci_bus *pci_bus);
+extern acpi_status pci_acpi_remove_pm_notifier(struct acpi_device *dev);
+
static inline acpi_handle acpi_find_root_bridge_handle(struct pci_dev *pdev)
{
struct pci_bus *pbus = pdev->bus;
===================================================================
@@ -26,7 +26,9 @@
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/pci.h>
+#include <linux/pci-acpi.h>
#include <linux/acpi.h>
+#include <linux/pm_runtime.h>
#include <acpi/acpi_bus.h>
#include <acpi/acpi_drivers.h>
@@ -38,7 +40,13 @@ static int acpi_pci_unbind(struct acpi_d
struct pci_dev *dev;
dev = acpi_get_pci_dev(device->handle);
- if (!dev || !dev->subordinate)
+ if (!dev)
+ goto out;
+
+ device_set_run_wake(&dev->dev, false);
+ pci_acpi_remove_pm_notifier(device);
+
+ if (!dev->subordinate)
goto out;
acpi_pci_irq_del_prt(dev->subordinate);
@@ -62,6 +70,10 @@ static int acpi_pci_bind(struct acpi_dev
if (!dev)
return 0;
+ pci_acpi_add_pm_notifier(device, dev, dev->subordinate);
+ if (device->wakeup.flags.run_wake)
+ device_set_run_wake(&dev->dev, true);
+
/*
* Install the 'bind' function to facilitate callbacks for
* children of the P2P bridge.
===================================================================
@@ -236,8 +236,7 @@ register_slot(acpi_handle handle, u32 lv
/* install notify handler */
if (!(newfunc->flags & FUNC_HAS_DCK)) {
- status = acpi_install_notify_handler(handle,
- ACPI_SYSTEM_NOTIFY,
+ status = pci_acpi_add_hp_notifier(handle,
handle_hotplug_event_func,
newfunc);
@@ -288,14 +287,12 @@ static void init_bridge_misc(struct acpi
/* install notify handler */
if (bridge->type != BRIDGE_TYPE_HOST) {
if ((bridge->flags & BRIDGE_HAS_EJ0) && bridge->func) {
- status = acpi_remove_notify_handler(bridge->func->handle,
- ACPI_SYSTEM_NOTIFY,
+ status = pci_acpi_remove_hp_notifier(bridge->func->handle,
handle_hotplug_event_func);
if (ACPI_FAILURE(status))
err("failed to remove notify handler\n");
}
- status = acpi_install_notify_handler(bridge->handle,
- ACPI_SYSTEM_NOTIFY,
+ status = pci_acpi_add_hp_notifier(bridge->handle,
handle_hotplug_event_bridge,
bridge);
@@ -505,15 +502,14 @@ static void cleanup_bridge(struct acpiph
acpi_status status;
acpi_handle handle = bridge->handle;
- status = acpi_remove_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
+ status = pci_acpi_remove_hp_notifier(handle,
handle_hotplug_event_bridge);
if (ACPI_FAILURE(status))
err("failed to remove notify handler\n");
if ((bridge->type != BRIDGE_TYPE_HOST) &&
((bridge->flags & BRIDGE_HAS_EJ0) && bridge->func)) {
- status = acpi_install_notify_handler(bridge->func->handle,
- ACPI_SYSTEM_NOTIFY,
+ status = pci_acpi_add_hp_notifier(bridge->func->handle,
handle_hotplug_event_func,
bridge->func);
if (ACPI_FAILURE(status))
@@ -529,8 +525,7 @@ static void cleanup_bridge(struct acpiph
unregister_dock_notifier(&func->nb);
}
if (!(func->flags & FUNC_HAS_DCK)) {
- status = acpi_remove_notify_handler(func->handle,
- ACPI_SYSTEM_NOTIFY,
+ status = pci_acpi_remove_hp_notifier(func->handle,
handle_hotplug_event_func);
if (ACPI_FAILURE(status))
err("failed to remove notify handler\n");
@@ -592,7 +587,7 @@ static void remove_bridge(acpi_handle ha
if (bridge)
cleanup_bridge(bridge);
else
- acpi_remove_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
+ pci_acpi_remove_hp_notifier(handle,
handle_hotplug_event_bridge);
}
@@ -1278,8 +1273,8 @@ find_root_bridges(acpi_handle handle, u3
int *count = (int *)context;
if (acpi_is_root_bridge(handle)) {
- acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
- handle_hotplug_event_bridge, NULL);
+ pci_acpi_add_hp_notifier(handle,
+ handle_hotplug_event_bridge, NULL);
(*count)++;
}
return AE_OK ;
===================================================================
@@ -756,6 +756,7 @@ int pci_wake_from_d3(struct pci_dev *dev
pci_power_t pci_target_state(struct pci_dev *dev);
int pci_prepare_to_sleep(struct pci_dev *dev);
int pci_back_from_sleep(struct pci_dev *dev);
+bool pci_dev_run_wake(struct pci_dev *dev);
/* Functions for PCI Hotplug drivers to use */
int pci_bus_find_capability(struct pci_bus *bus, unsigned int devfn, int cap);
===================================================================
@@ -282,6 +282,7 @@ struct acpi_device {
struct device dev;
struct acpi_bus_ops bus_ops; /* workaround for different code path for hotplug */
enum acpi_bus_removal_type removal_type; /* indicate for different removal type */
+ void *bus_data;
};
static inline void *acpi_driver_data(struct acpi_device *d)
@@ -388,6 +389,9 @@ acpi_handle acpi_get_pci_rootbridge_hand
struct acpi_pci_root *acpi_pci_find_root(acpi_handle handle);
#define DEVICE_ACPI_HANDLE(dev) ((acpi_handle)((dev)->archdata.acpi_handle))
+int acpi_enable_wakeup_device_power(struct acpi_device *dev, int state);
+int acpi_disable_wakeup_device_power(struct acpi_device *dev);
+
#ifdef CONFIG_PM_SLEEP
int acpi_pm_device_sleep_state(struct device *, int *);
int acpi_pm_device_sleep_wake(struct device *, bool);
===================================================================
@@ -30,6 +30,7 @@
#include <linux/proc_fs.h>
#include <linux/spinlock.h>
#include <linux/pm.h>
+#include <linux/pm_runtime.h>
#include <linux/pci.h>
#include <linux/pci-acpi.h>
#include <linux/acpi.h>
@@ -528,6 +529,10 @@ static int __devinit acpi_pci_root_add(s
if (flags != base_flags)
acpi_pci_osc_support(root, flags);
+ pci_acpi_add_pm_notifier(device, NULL, root->bus);
+ if (device->wakeup.flags.run_wake)
+ device_set_run_wake(root->bus->bridge, true);
+
return 0;
end:
@@ -549,6 +554,9 @@ static int acpi_pci_root_remove(struct a
{
struct acpi_pci_root *root = acpi_driver_data(device);
+ device_set_run_wake(root->bus->bridge, false);
+ pci_acpi_remove_pm_notifier(device);
+
kfree(root);
return 0;
}
===================================================================
@@ -36,8 +36,6 @@ static inline int acpi_debug_init(void)
int acpi_power_init(void);
int acpi_device_sleep_wake(struct acpi_device *dev,
int enable, int sleep_state, int dev_state);
-int acpi_enable_wakeup_device_power(struct acpi_device *dev, int sleep_state);
-int acpi_disable_wakeup_device_power(struct acpi_device *dev);
int acpi_power_get_inferred_state(struct acpi_device *device);
int acpi_power_transition(struct acpi_device *device, int state);
extern int acpi_power_nocheck;