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-rw-r--r--drivers/base/power/Makefile6
-rw-r--r--drivers/base/power/main.c784
-rw-r--r--drivers/base/power/power.h49
-rw-r--r--drivers/base/power/sysfs.c98
-rw-r--r--drivers/base/power/trace.c231
5 files changed, 1168 insertions, 0 deletions
diff --git a/drivers/base/power/Makefile b/drivers/base/power/Makefile
new file mode 100644
index 0000000..911208b
--- /dev/null
+++ b/drivers/base/power/Makefile
@@ -0,0 +1,6 @@
+obj-$(CONFIG_PM) += sysfs.o
+obj-$(CONFIG_PM_SLEEP) += main.o
+obj-$(CONFIG_PM_TRACE_RTC) += trace.o
+
+ccflags-$(CONFIG_DEBUG_DRIVER) := -DDEBUG
+ccflags-$(CONFIG_PM_VERBOSE) += -DDEBUG
diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c
new file mode 100644
index 0000000..692c20b
--- /dev/null
+++ b/drivers/base/power/main.c
@@ -0,0 +1,784 @@
+/*
+ * drivers/base/power/main.c - Where the driver meets power management.
+ *
+ * Copyright (c) 2003 Patrick Mochel
+ * Copyright (c) 2003 Open Source Development Lab
+ *
+ * This file is released under the GPLv2
+ *
+ *
+ * The driver model core calls device_pm_add() when a device is registered.
+ * This will intialize the embedded device_pm_info object in the device
+ * and add it to the list of power-controlled devices. sysfs entries for
+ * controlling device power management will also be added.
+ *
+ * A separate list is used for keeping track of power info, because the power
+ * domain dependencies may differ from the ancestral dependencies that the
+ * subsystem list maintains.
+ */
+
+#include <linux/device.h>
+#include <linux/kallsyms.h>
+#include <linux/mutex.h>
+#include <linux/pm.h>
+#include <linux/resume-trace.h>
+#include <linux/rwsem.h>
+
+#include "../base.h"
+#include "power.h"
+
+/*
+ * The entries in the dpm_list list are in a depth first order, simply
+ * because children are guaranteed to be discovered after parents, and
+ * are inserted at the back of the list on discovery.
+ *
+ * Since device_pm_add() may be called with a device semaphore held,
+ * we must never try to acquire a device semaphore while holding
+ * dpm_list_mutex.
+ */
+
+LIST_HEAD(dpm_list);
+
+static DEFINE_MUTEX(dpm_list_mtx);
+
+/*
+ * Set once the preparation of devices for a PM transition has started, reset
+ * before starting to resume devices. Protected by dpm_list_mtx.
+ */
+static bool transition_started;
+
+/**
+ * device_pm_lock - lock the list of active devices used by the PM core
+ */
+void device_pm_lock(void)
+{
+ mutex_lock(&dpm_list_mtx);
+}
+
+/**
+ * device_pm_unlock - unlock the list of active devices used by the PM core
+ */
+void device_pm_unlock(void)
+{
+ mutex_unlock(&dpm_list_mtx);
+}
+
+/**
+ * device_pm_add - add a device to the list of active devices
+ * @dev: Device to be added to the list
+ */
+void device_pm_add(struct device *dev)
+{
+ pr_debug("PM: Adding info for %s:%s\n",
+ dev->bus ? dev->bus->name : "No Bus",
+ kobject_name(&dev->kobj));
+ mutex_lock(&dpm_list_mtx);
+ if (dev->parent) {
+ if (dev->parent->power.status >= DPM_SUSPENDING)
+ dev_warn(dev, "parent %s should not be sleeping\n",
+ dev->parent->bus_id);
+ } else if (transition_started) {
+ /*
+ * We refuse to register parentless devices while a PM
+ * transition is in progress in order to avoid leaving them
+ * unhandled down the road
+ */
+ dev_WARN(dev, "Parentless device registered during a PM transaction\n");
+ }
+
+ list_add_tail(&dev->power.entry, &dpm_list);
+ mutex_unlock(&dpm_list_mtx);
+}
+
+/**
+ * device_pm_remove - remove a device from the list of active devices
+ * @dev: Device to be removed from the list
+ *
+ * This function also removes the device's PM-related sysfs attributes.
+ */
+void device_pm_remove(struct device *dev)
+{
+ pr_debug("PM: Removing info for %s:%s\n",
+ dev->bus ? dev->bus->name : "No Bus",
+ kobject_name(&dev->kobj));
+ mutex_lock(&dpm_list_mtx);
+ list_del_init(&dev->power.entry);
+ mutex_unlock(&dpm_list_mtx);
+}
+
+/**
+ * pm_op - execute the PM operation appropiate for given PM event
+ * @dev: Device.
+ * @ops: PM operations to choose from.
+ * @state: PM transition of the system being carried out.
+ */
+static int pm_op(struct device *dev, struct pm_ops *ops, pm_message_t state)
+{
+ int error = 0;
+
+ switch (state.event) {
+#ifdef CONFIG_SUSPEND
+ case PM_EVENT_SUSPEND:
+ if (ops->suspend) {
+ error = ops->suspend(dev);
+ suspend_report_result(ops->suspend, error);
+ }
+ break;
+ case PM_EVENT_RESUME:
+ if (ops->resume) {
+ error = ops->resume(dev);
+ suspend_report_result(ops->resume, error);
+ }
+ break;
+#endif /* CONFIG_SUSPEND */
+#ifdef CONFIG_HIBERNATION
+ case PM_EVENT_FREEZE:
+ case PM_EVENT_QUIESCE:
+ if (ops->freeze) {
+ error = ops->freeze(dev);
+ suspend_report_result(ops->freeze, error);
+ }
+ break;
+ case PM_EVENT_HIBERNATE:
+ if (ops->poweroff) {
+ error = ops->poweroff(dev);
+ suspend_report_result(ops->poweroff, error);
+ }
+ break;
+ case PM_EVENT_THAW:
+ case PM_EVENT_RECOVER:
+ if (ops->thaw) {
+ error = ops->thaw(dev);
+ suspend_report_result(ops->thaw, error);
+ }
+ break;
+ case PM_EVENT_RESTORE:
+ if (ops->restore) {
+ error = ops->restore(dev);
+ suspend_report_result(ops->restore, error);
+ }
+ break;
+#endif /* CONFIG_HIBERNATION */
+ default:
+ error = -EINVAL;
+ }
+ return error;
+}
+
+/**
+ * pm_noirq_op - execute the PM operation appropiate for given PM event
+ * @dev: Device.
+ * @ops: PM operations to choose from.
+ * @state: PM transition of the system being carried out.
+ *
+ * The operation is executed with interrupts disabled by the only remaining
+ * functional CPU in the system.
+ */
+static int pm_noirq_op(struct device *dev, struct pm_ext_ops *ops,
+ pm_message_t state)
+{
+ int error = 0;
+
+ switch (state.event) {
+#ifdef CONFIG_SUSPEND
+ case PM_EVENT_SUSPEND:
+ if (ops->suspend_noirq) {
+ error = ops->suspend_noirq(dev);
+ suspend_report_result(ops->suspend_noirq, error);
+ }
+ break;
+ case PM_EVENT_RESUME:
+ if (ops->resume_noirq) {
+ error = ops->resume_noirq(dev);
+ suspend_report_result(ops->resume_noirq, error);
+ }
+ break;
+#endif /* CONFIG_SUSPEND */
+#ifdef CONFIG_HIBERNATION
+ case PM_EVENT_FREEZE:
+ case PM_EVENT_QUIESCE:
+ if (ops->freeze_noirq) {
+ error = ops->freeze_noirq(dev);
+ suspend_report_result(ops->freeze_noirq, error);
+ }
+ break;
+ case PM_EVENT_HIBERNATE:
+ if (ops->poweroff_noirq) {
+ error = ops->poweroff_noirq(dev);
+ suspend_report_result(ops->poweroff_noirq, error);
+ }
+ break;
+ case PM_EVENT_THAW:
+ case PM_EVENT_RECOVER:
+ if (ops->thaw_noirq) {
+ error = ops->thaw_noirq(dev);
+ suspend_report_result(ops->thaw_noirq, error);
+ }
+ break;
+ case PM_EVENT_RESTORE:
+ if (ops->restore_noirq) {
+ error = ops->restore_noirq(dev);
+ suspend_report_result(ops->restore_noirq, error);
+ }
+ break;
+#endif /* CONFIG_HIBERNATION */
+ default:
+ error = -EINVAL;
+ }
+ return error;
+}
+
+static char *pm_verb(int event)
+{
+ switch (event) {
+ case PM_EVENT_SUSPEND:
+ return "suspend";
+ case PM_EVENT_RESUME:
+ return "resume";
+ case PM_EVENT_FREEZE:
+ return "freeze";
+ case PM_EVENT_QUIESCE:
+ return "quiesce";
+ case PM_EVENT_HIBERNATE:
+ return "hibernate";
+ case PM_EVENT_THAW:
+ return "thaw";
+ case PM_EVENT_RESTORE:
+ return "restore";
+ case PM_EVENT_RECOVER:
+ return "recover";
+ default:
+ return "(unknown PM event)";
+ }
+}
+
+static void pm_dev_dbg(struct device *dev, pm_message_t state, char *info)
+{
+ dev_dbg(dev, "%s%s%s\n", info, pm_verb(state.event),
+ ((state.event & PM_EVENT_SLEEP) && device_may_wakeup(dev)) ?
+ ", may wakeup" : "");
+}
+
+static void pm_dev_err(struct device *dev, pm_message_t state, char *info,
+ int error)
+{
+ printk(KERN_ERR "PM: Device %s failed to %s%s: error %d\n",
+ kobject_name(&dev->kobj), pm_verb(state.event), info, error);
+}
+
+/*------------------------- Resume routines -------------------------*/
+
+/**
+ * resume_device_noirq - Power on one device (early resume).
+ * @dev: Device.
+ * @state: PM transition of the system being carried out.
+ *
+ * Must be called with interrupts disabled.
+ */
+static int resume_device_noirq(struct device *dev, pm_message_t state)
+{
+ int error = 0;
+
+ TRACE_DEVICE(dev);
+ TRACE_RESUME(0);
+
+ if (!dev->bus)
+ goto End;
+
+ if (dev->bus->pm) {
+ pm_dev_dbg(dev, state, "EARLY ");
+ error = pm_noirq_op(dev, dev->bus->pm, state);
+ } else if (dev->bus->resume_early) {
+ pm_dev_dbg(dev, state, "legacy EARLY ");
+ error = dev->bus->resume_early(dev);
+ }
+ End:
+ TRACE_RESUME(error);
+ return error;
+}
+
+/**
+ * dpm_power_up - Power on all regular (non-sysdev) devices.
+ * @state: PM transition of the system being carried out.
+ *
+ * Execute the appropriate "noirq resume" callback for all devices marked
+ * as DPM_OFF_IRQ.
+ *
+ * Must be called with interrupts disabled and only one CPU running.
+ */
+static void dpm_power_up(pm_message_t state)
+{
+ struct device *dev;
+
+ list_for_each_entry(dev, &dpm_list, power.entry)
+ if (dev->power.status > DPM_OFF) {
+ int error;
+
+ dev->power.status = DPM_OFF;
+ error = resume_device_noirq(dev, state);
+ if (error)
+ pm_dev_err(dev, state, " early", error);
+ }
+}
+
+/**
+ * device_power_up - Turn on all devices that need special attention.
+ * @state: PM transition of the system being carried out.
+ *
+ * Power on system devices, then devices that required we shut them down
+ * with interrupts disabled.
+ *
+ * Must be called with interrupts disabled.
+ */
+void device_power_up(pm_message_t state)
+{
+ sysdev_resume();
+ dpm_power_up(state);
+}
+EXPORT_SYMBOL_GPL(device_power_up);
+
+/**
+ * resume_device - Restore state for one device.
+ * @dev: Device.
+ * @state: PM transition of the system being carried out.
+ */
+static int resume_device(struct device *dev, pm_message_t state)
+{
+ int error = 0;
+
+ TRACE_DEVICE(dev);
+ TRACE_RESUME(0);
+
+ down(&dev->sem);
+
+ if (dev->bus) {
+ if (dev->bus->pm) {
+ pm_dev_dbg(dev, state, "");
+ error = pm_op(dev, &dev->bus->pm->base, state);
+ } else if (dev->bus->resume) {
+ pm_dev_dbg(dev, state, "legacy ");
+ error = dev->bus->resume(dev);
+ }
+ if (error)
+ goto End;
+ }
+
+ if (dev->type) {
+ if (dev->type->pm) {
+ pm_dev_dbg(dev, state, "type ");
+ error = pm_op(dev, dev->type->pm, state);
+ } else if (dev->type->resume) {
+ pm_dev_dbg(dev, state, "legacy type ");
+ error = dev->type->resume(dev);
+ }
+ if (error)
+ goto End;
+ }
+
+ if (dev->class) {
+ if (dev->class->pm) {
+ pm_dev_dbg(dev, state, "class ");
+ error = pm_op(dev, dev->class->pm, state);
+ } else if (dev->class->resume) {
+ pm_dev_dbg(dev, state, "legacy class ");
+ error = dev->class->resume(dev);
+ }
+ }
+ End:
+ up(&dev->sem);
+
+ TRACE_RESUME(error);
+ return error;
+}
+
+/**
+ * dpm_resume - Resume every device.
+ * @state: PM transition of the system being carried out.
+ *
+ * Execute the appropriate "resume" callback for all devices the status of
+ * which indicates that they are inactive.
+ */
+static void dpm_resume(pm_message_t state)
+{
+ struct list_head list;
+
+ INIT_LIST_HEAD(&list);
+ mutex_lock(&dpm_list_mtx);
+ transition_started = false;
+ while (!list_empty(&dpm_list)) {
+ struct device *dev = to_device(dpm_list.next);
+
+ get_device(dev);
+ if (dev->power.status >= DPM_OFF) {
+ int error;
+
+ dev->power.status = DPM_RESUMING;
+ mutex_unlock(&dpm_list_mtx);
+
+ error = resume_device(dev, state);
+
+ mutex_lock(&dpm_list_mtx);
+ if (error)
+ pm_dev_err(dev, state, "", error);
+ } else if (dev->power.status == DPM_SUSPENDING) {
+ /* Allow new children of the device to be registered */
+ dev->power.status = DPM_RESUMING;
+ }
+ if (!list_empty(&dev->power.entry))
+ list_move_tail(&dev->power.entry, &list);
+ put_device(dev);
+ }
+ list_splice(&list, &dpm_list);
+ mutex_unlock(&dpm_list_mtx);
+}
+
+/**
+ * complete_device - Complete a PM transition for given device
+ * @dev: Device.
+ * @state: PM transition of the system being carried out.
+ */
+static void complete_device(struct device *dev, pm_message_t state)
+{
+ down(&dev->sem);
+
+ if (dev->class && dev->class->pm && dev->class->pm->complete) {
+ pm_dev_dbg(dev, state, "completing class ");
+ dev->class->pm->complete(dev);
+ }
+
+ if (dev->type && dev->type->pm && dev->type->pm->complete) {
+ pm_dev_dbg(dev, state, "completing type ");
+ dev->type->pm->complete(dev);
+ }
+
+ if (dev->bus && dev->bus->pm && dev->bus->pm->base.complete) {
+ pm_dev_dbg(dev, state, "completing ");
+ dev->bus->pm->base.complete(dev);
+ }
+
+ up(&dev->sem);
+}
+
+/**
+ * dpm_complete - Complete a PM transition for all devices.
+ * @state: PM transition of the system being carried out.
+ *
+ * Execute the ->complete() callbacks for all devices that are not marked
+ * as DPM_ON.
+ */
+static void dpm_complete(pm_message_t state)
+{
+ struct list_head list;
+
+ INIT_LIST_HEAD(&list);
+ mutex_lock(&dpm_list_mtx);
+ while (!list_empty(&dpm_list)) {
+ struct device *dev = to_device(dpm_list.prev);
+
+ get_device(dev);
+ if (dev->power.status > DPM_ON) {
+ dev->power.status = DPM_ON;
+ mutex_unlock(&dpm_list_mtx);
+
+ complete_device(dev, state);
+
+ mutex_lock(&dpm_list_mtx);
+ }
+ if (!list_empty(&dev->power.entry))
+ list_move(&dev->power.entry, &list);
+ put_device(dev);
+ }
+ list_splice(&list, &dpm_list);
+ mutex_unlock(&dpm_list_mtx);
+}
+
+/**
+ * device_resume - Restore state of each device in system.
+ * @state: PM transition of the system being carried out.
+ *
+ * Resume all the devices, unlock them all, and allow new
+ * devices to be registered once again.
+ */
+void device_resume(pm_message_t state)
+{
+ might_sleep();
+ dpm_resume(state);
+ dpm_complete(state);
+}
+EXPORT_SYMBOL_GPL(device_resume);
+
+
+/*------------------------- Suspend routines -------------------------*/
+
+/**
+ * resume_event - return a PM message representing the resume event
+ * corresponding to given sleep state.
+ * @sleep_state: PM message representing a sleep state.
+ */
+static pm_message_t resume_event(pm_message_t sleep_state)
+{
+ switch (sleep_state.event) {
+ case PM_EVENT_SUSPEND:
+ return PMSG_RESUME;
+ case PM_EVENT_FREEZE:
+ case PM_EVENT_QUIESCE:
+ return PMSG_RECOVER;
+ case PM_EVENT_HIBERNATE:
+ return PMSG_RESTORE;
+ }
+ return PMSG_ON;
+}
+
+/**
+ * suspend_device_noirq - Shut down one device (late suspend).
+ * @dev: Device.
+ * @state: PM transition of the system being carried out.
+ *
+ * This is called with interrupts off and only a single CPU running.
+ */
+static int suspend_device_noirq(struct device *dev, pm_message_t state)
+{
+ int error = 0;
+
+ if (!dev->bus)
+ return 0;
+
+ if (dev->bus->pm) {
+ pm_dev_dbg(dev, state, "LATE ");
+ error = pm_noirq_op(dev, dev->bus->pm, state);
+ } else if (dev->bus->suspend_late) {
+ pm_dev_dbg(dev, state, "legacy LATE ");
+ error = dev->bus->suspend_late(dev, state);
+ suspend_report_result(dev->bus->suspend_late, error);
+ }
+ return error;
+}
+
+/**
+ * device_power_down - Shut down special devices.
+ * @state: PM transition of the system being carried out.
+ *
+ * Power down devices that require interrupts to be disabled.
+ * Then power down system devices.
+ *
+ * Must be called with interrupts disabled and only one CPU running.
+ */
+int device_power_down(pm_message_t state)
+{
+ struct device *dev;
+ int error = 0;
+
+ list_for_each_entry_reverse(dev, &dpm_list, power.entry) {
+ error = suspend_device_noirq(dev, state);
+ if (error) {
+ pm_dev_err(dev, state, " late", error);
+ break;
+ }
+ dev->power.status = DPM_OFF_IRQ;
+ }
+ if (!error)
+ error = sysdev_suspend(state);
+ if (error)
+ dpm_power_up(resume_event(state));
+ return error;
+}
+EXPORT_SYMBOL_GPL(device_power_down);
+
+/**
+ * suspend_device - Save state of one device.
+ * @dev: Device.
+ * @state: PM transition of the system being carried out.
+ */
+static int suspend_device(struct device *dev, pm_message_t state)
+{
+ int error = 0;
+
+ down(&dev->sem);
+
+ if (dev->class) {
+ if (dev->class->pm) {
+ pm_dev_dbg(dev, state, "class ");
+ error = pm_op(dev, dev->class->pm, state);
+ } else if (dev->class->suspend) {
+ pm_dev_dbg(dev, state, "legacy class ");
+ error = dev->class->suspend(dev, state);
+ suspend_report_result(dev->class->suspend, error);
+ }
+ if (error)
+ goto End;
+ }
+
+ if (dev->type) {
+ if (dev->type->pm) {
+ pm_dev_dbg(dev, state, "type ");
+ error = pm_op(dev, dev->type->pm, state);
+ } else if (dev->type->suspend) {
+ pm_dev_dbg(dev, state, "legacy type ");
+ error = dev->type->suspend(dev, state);
+ suspend_report_result(dev->type->suspend, error);
+ }
+ if (error)
+ goto End;
+ }
+
+ if (dev->bus) {
+ if (dev->bus->pm) {
+ pm_dev_dbg(dev, state, "");
+ error = pm_op(dev, &dev->bus->pm->base, state);
+ } else if (dev->bus->suspend) {
+ pm_dev_dbg(dev, state, "legacy ");
+ error = dev->bus->suspend(dev, state);
+ suspend_report_result(dev->bus->suspend, error);
+ }
+ }
+ End:
+ up(&dev->sem);
+
+ return error;
+}
+
+/**
+ * dpm_suspend - Suspend every device.
+ * @state: PM transition of the system being carried out.
+ *
+ * Execute the appropriate "suspend" callbacks for all devices.
+ */
+static int dpm_suspend(pm_message_t state)
+{
+ struct list_head list;
+ int error = 0;
+
+ INIT_LIST_HEAD(&list);
+ mutex_lock(&dpm_list_mtx);
+ while (!list_empty(&dpm_list)) {
+ struct device *dev = to_device(dpm_list.prev);
+
+ get_device(dev);
+ mutex_unlock(&dpm_list_mtx);
+
+ error = suspend_device(dev, state);
+
+ mutex_lock(&dpm_list_mtx);
+ if (error) {
+ pm_dev_err(dev, state, "", error);
+ put_device(dev);
+ break;
+ }
+ dev->power.status = DPM_OFF;
+ if (!list_empty(&dev->power.entry))
+ list_move(&dev->power.entry, &list);
+ put_device(dev);
+ }
+ list_splice(&list, dpm_list.prev);
+ mutex_unlock(&dpm_list_mtx);
+ return error;
+}
+
+/**
+ * prepare_device - Execute the ->prepare() callback(s) for given device.
+ * @dev: Device.
+ * @state: PM transition of the system being carried out.
+ */
+static int prepare_device(struct device *dev, pm_message_t state)
+{
+ int error = 0;
+
+ down(&dev->sem);
+
+ if (dev->bus && dev->bus->pm && dev->bus->pm->base.prepare) {
+ pm_dev_dbg(dev, state, "preparing ");
+ error = dev->bus->pm->base.prepare(dev);
+ suspend_report_result(dev->bus->pm->base.prepare, error);
+ if (error)
+ goto End;
+ }
+
+ if (dev->type && dev->type->pm && dev->type->pm->prepare) {
+ pm_dev_dbg(dev, state, "preparing type ");
+ error = dev->type->pm->prepare(dev);
+ suspend_report_result(dev->type->pm->prepare, error);
+ if (error)
+ goto End;
+ }
+
+ if (dev->class && dev->class->pm && dev->class->pm->prepare) {
+ pm_dev_dbg(dev, state, "preparing class ");
+ error = dev->class->pm->prepare(dev);
+ suspend_report_result(dev->class->pm->prepare, error);
+ }
+ End:
+ up(&dev->sem);
+
+ return error;
+}
+
+/**
+ * dpm_prepare - Prepare all devices for a PM transition.
+ * @state: PM transition of the system being carried out.
+ *
+ * Execute the ->prepare() callback for all devices.
+ */
+static int dpm_prepare(pm_message_t state)
+{
+ struct list_head list;
+ int error = 0;
+
+ INIT_LIST_HEAD(&list);
+ mutex_lock(&dpm_list_mtx);
+ transition_started = true;
+ while (!list_empty(&dpm_list)) {
+ struct device *dev = to_device(dpm_list.next);
+
+ get_device(dev);
+ dev->power.status = DPM_PREPARING;
+ mutex_unlock(&dpm_list_mtx);
+
+ error = prepare_device(dev, state);
+
+ mutex_lock(&dpm_list_mtx);
+ if (error) {
+ dev->power.status = DPM_ON;
+ if (error == -EAGAIN) {
+ put_device(dev);
+ continue;
+ }
+ printk(KERN_ERR "PM: Failed to prepare device %s "
+ "for power transition: error %d\n",
+ kobject_name(&dev->kobj), error);
+ put_device(dev);
+ break;
+ }
+ dev->power.status = DPM_SUSPENDING;
+ if (!list_empty(&dev->power.entry))
+ list_move_tail(&dev->power.entry, &list);
+ put_device(dev);
+ }
+ list_splice(&list, &dpm_list);
+ mutex_unlock(&dpm_list_mtx);
+ return error;
+}
+
+/**
+ * device_suspend - Save state and stop all devices in system.
+ * @state: PM transition of the system being carried out.
+ *
+ * Prepare and suspend all devices.
+ */
+int device_suspend(pm_message_t state)
+{
+ int error;
+
+ might_sleep();
+ error = dpm_prepare(state);
+ if (!error)
+ error = dpm_suspend(state);
+ return error;
+}
+EXPORT_SYMBOL_GPL(device_suspend);
+
+void __suspend_report_result(const char *function, void *fn, int ret)
+{
+ if (ret)
+ printk(KERN_ERR "%s(): %pF returns %d\n", function, fn, ret);
+}
+EXPORT_SYMBOL_GPL(__suspend_report_result);
diff --git a/drivers/base/power/power.h b/drivers/base/power/power.h
new file mode 100644
index 0000000..41f51fa
--- /dev/null
+++ b/drivers/base/power/power.h
@@ -0,0 +1,49 @@
+static inline void device_pm_init(struct device *dev)
+{
+ dev->power.status = DPM_ON;
+}
+
+#ifdef CONFIG_PM_SLEEP
+
+/*
+ * main.c
+ */
+
+extern struct list_head dpm_list; /* The active device list */
+
+static inline struct device *to_device(struct list_head *entry)
+{
+ return container_of(entry, struct device, power.entry);
+}
+
+extern void device_pm_add(struct device *);
+extern void device_pm_remove(struct device *);
+
+#else /* CONFIG_PM_SLEEP */
+
+static inline void device_pm_add(struct device *dev) {}
+static inline void device_pm_remove(struct device *dev) {}
+
+#endif
+
+#ifdef CONFIG_PM
+
+/*
+ * sysfs.c
+ */
+
+extern int dpm_sysfs_add(struct device *);
+extern void dpm_sysfs_remove(struct device *);
+
+#else /* CONFIG_PM */
+
+static inline int dpm_sysfs_add(struct device *dev)
+{
+ return 0;
+}
+
+static inline void dpm_sysfs_remove(struct device *dev)
+{
+}
+
+#endif
diff --git a/drivers/base/power/sysfs.c b/drivers/base/power/sysfs.c
new file mode 100644
index 0000000..596aeec
--- /dev/null
+++ b/drivers/base/power/sysfs.c
@@ -0,0 +1,98 @@
+/*
+ * drivers/base/power/sysfs.c - sysfs entries for device PM
+ */
+
+#include <linux/device.h>
+#include <linux/string.h>
+#include "power.h"
+
+/*
+ * wakeup - Report/change current wakeup option for device
+ *
+ * Some devices support "wakeup" events, which are hardware signals
+ * used to activate devices from suspended or low power states. Such
+ * devices have one of three values for the sysfs power/wakeup file:
+ *
+ * + "enabled\n" to issue the events;
+ * + "disabled\n" not to do so; or
+ * + "\n" for temporary or permanent inability to issue wakeup.
+ *
+ * (For example, unconfigured USB devices can't issue wakeups.)
+ *
+ * Familiar examples of devices that can issue wakeup events include
+ * keyboards and mice (both PS2 and USB styles), power buttons, modems,
+ * "Wake-On-LAN" Ethernet links, GPIO lines, and more. Some events
+ * will wake the entire system from a suspend state; others may just
+ * wake up the device (if the system as a whole is already active).
+ * Some wakeup events use normal IRQ lines; other use special out
+ * of band signaling.
+ *
+ * It is the responsibility of device drivers to enable (or disable)
+ * wakeup signaling as part of changing device power states, respecting
+ * the policy choices provided through the driver model.
+ *
+ * Devices may not be able to generate wakeup events from all power
+ * states. Also, the events may be ignored in some configurations;
+ * for example, they might need help from other devices that aren't
+ * active, or which may have wakeup disabled. Some drivers rely on
+ * wakeup events internally (unless they are disabled), keeping
+ * their hardware in low power modes whenever they're unused. This
+ * saves runtime power, without requiring system-wide sleep states.
+ */
+
+static const char enabled[] = "enabled";
+static const char disabled[] = "disabled";
+
+static ssize_t
+wake_show(struct device * dev, struct device_attribute *attr, char * buf)
+{
+ return sprintf(buf, "%s\n", device_can_wakeup(dev)
+ ? (device_may_wakeup(dev) ? enabled : disabled)
+ : "");
+}
+
+static ssize_t
+wake_store(struct device * dev, struct device_attribute *attr,
+ const char * buf, size_t n)
+{
+ char *cp;
+ int len = n;
+
+ if (!device_can_wakeup(dev))
+ return -EINVAL;
+
+ cp = memchr(buf, '\n', n);
+ if (cp)
+ len = cp - buf;
+ if (len == sizeof enabled - 1
+ && strncmp(buf, enabled, sizeof enabled - 1) == 0)
+ device_set_wakeup_enable(dev, 1);
+ else if (len == sizeof disabled - 1
+ && strncmp(buf, disabled, sizeof disabled - 1) == 0)
+ device_set_wakeup_enable(dev, 0);
+ else
+ return -EINVAL;
+ return n;
+}
+
+static DEVICE_ATTR(wakeup, 0644, wake_show, wake_store);
+
+
+static struct attribute * power_attrs[] = {
+ &dev_attr_wakeup.attr,
+ NULL,
+};
+static struct attribute_group pm_attr_group = {
+ .name = "power",
+ .attrs = power_attrs,
+};
+
+int dpm_sysfs_add(struct device * dev)
+{
+ return sysfs_create_group(&dev->kobj, &pm_attr_group);
+}
+
+void dpm_sysfs_remove(struct device * dev)
+{
+ sysfs_remove_group(&dev->kobj, &pm_attr_group);
+}
diff --git a/drivers/base/power/trace.c b/drivers/base/power/trace.c
new file mode 100644
index 0000000..2aa6e8f
--- /dev/null
+++ b/drivers/base/power/trace.c
@@ -0,0 +1,231 @@
+/*
+ * drivers/base/power/trace.c
+ *
+ * Copyright (C) 2006 Linus Torvalds
+ *
+ * Trace facility for suspend/resume problems, when none of the
+ * devices may be working.
+ */
+
+#include <linux/resume-trace.h>
+#include <linux/rtc.h>
+
+#include <asm/rtc.h>
+
+#include "power.h"
+
+/*
+ * Horrid, horrid, horrid.
+ *
+ * It turns out that the _only_ piece of hardware that actually
+ * keeps its value across a hard boot (and, more importantly, the
+ * POST init sequence) is literally the realtime clock.
+ *
+ * Never mind that an RTC chip has 114 bytes (and often a whole
+ * other bank of an additional 128 bytes) of nice SRAM that is
+ * _designed_ to keep data - the POST will clear it. So we literally
+ * can just use the few bytes of actual time data, which means that
+ * we're really limited.
+ *
+ * It means, for example, that we can't use the seconds at all
+ * (since the time between the hang and the boot might be more
+ * than a minute), and we'd better not depend on the low bits of
+ * the minutes either.
+ *
+ * There are the wday fields etc, but I wouldn't guarantee those
+ * are dependable either. And if the date isn't valid, either the
+ * hw or POST will do strange things.
+ *
+ * So we're left with:
+ * - year: 0-99
+ * - month: 0-11
+ * - day-of-month: 1-28
+ * - hour: 0-23
+ * - min: (0-30)*2
+ *
+ * Giving us a total range of 0-16128000 (0xf61800), ie less
+ * than 24 bits of actual data we can save across reboots.
+ *
+ * And if your box can't boot in less than three minutes,
+ * you're screwed.
+ *
+ * Now, almost 24 bits of data is pitifully small, so we need
+ * to be pretty dense if we want to use it for anything nice.
+ * What we do is that instead of saving off nice readable info,
+ * we save off _hashes_ of information that we can hopefully
+ * regenerate after the reboot.
+ *
+ * In particular, this means that we might be unlucky, and hit
+ * a case where we have a hash collision, and we end up not
+ * being able to tell for certain exactly which case happened.
+ * But that's hopefully unlikely.
+ *
+ * What we do is to take the bits we can fit, and split them
+ * into three parts (16*997*1009 = 16095568), and use the values
+ * for:
+ * - 0-15: user-settable
+ * - 0-996: file + line number
+ * - 0-1008: device
+ */
+#define USERHASH (16)
+#define FILEHASH (997)
+#define DEVHASH (1009)
+
+#define DEVSEED (7919)
+
+static unsigned int dev_hash_value;
+
+static int set_magic_time(unsigned int user, unsigned int file, unsigned int device)
+{
+ unsigned int n = user + USERHASH*(file + FILEHASH*device);
+
+ // June 7th, 2006
+ static struct rtc_time time = {
+ .tm_sec = 0,
+ .tm_min = 0,
+ .tm_hour = 0,
+ .tm_mday = 7,
+ .tm_mon = 5, // June - counting from zero
+ .tm_year = 106,
+ .tm_wday = 3,
+ .tm_yday = 160,
+ .tm_isdst = 1
+ };
+
+ time.tm_year = (n % 100);
+ n /= 100;
+ time.tm_mon = (n % 12);
+ n /= 12;
+ time.tm_mday = (n % 28) + 1;
+ n /= 28;
+ time.tm_hour = (n % 24);
+ n /= 24;
+ time.tm_min = (n % 20) * 3;
+ n /= 20;
+ set_rtc_time(&time);
+ return n ? -1 : 0;
+}
+
+static unsigned int read_magic_time(void)
+{
+ struct rtc_time time;
+ unsigned int val;
+
+ get_rtc_time(&time);
+ printk("Time: %2d:%02d:%02d Date: %02d/%02d/%02d\n",
+ time.tm_hour, time.tm_min, time.tm_sec,
+ time.tm_mon + 1, time.tm_mday, time.tm_year % 100);
+ val = time.tm_year; /* 100 years */
+ if (val > 100)
+ val -= 100;
+ val += time.tm_mon * 100; /* 12 months */
+ val += (time.tm_mday-1) * 100 * 12; /* 28 month-days */
+ val += time.tm_hour * 100 * 12 * 28; /* 24 hours */
+ val += (time.tm_min / 3) * 100 * 12 * 28 * 24; /* 20 3-minute intervals */
+ return val;
+}
+
+/*
+ * This is just the sdbm hash function with a user-supplied
+ * seed and final size parameter.
+ */
+static unsigned int hash_string(unsigned int seed, const char *data, unsigned int mod)
+{
+ unsigned char c;
+ while ((c = *data++) != 0) {
+ seed = (seed << 16) + (seed << 6) - seed + c;
+ }
+ return seed % mod;
+}
+
+void set_trace_device(struct device *dev)
+{
+ dev_hash_value = hash_string(DEVSEED, dev->bus_id, DEVHASH);
+}
+EXPORT_SYMBOL(set_trace_device);
+
+/*
+ * We could just take the "tracedata" index into the .tracedata
+ * section instead. Generating a hash of the data gives us a
+ * chance to work across kernel versions, and perhaps more
+ * importantly it also gives us valid/invalid check (ie we will
+ * likely not give totally bogus reports - if the hash matches,
+ * it's not any guarantee, but it's a high _likelihood_ that
+ * the match is valid).
+ */
+void generate_resume_trace(const void *tracedata, unsigned int user)
+{
+ unsigned short lineno = *(unsigned short *)tracedata;
+ const char *file = *(const char **)(tracedata + 2);
+ unsigned int user_hash_value, file_hash_value;
+
+ user_hash_value = user % USERHASH;
+ file_hash_value = hash_string(lineno, file, FILEHASH);
+ set_magic_time(user_hash_value, file_hash_value, dev_hash_value);
+}
+EXPORT_SYMBOL(generate_resume_trace);
+
+extern char __tracedata_start, __tracedata_end;
+static int show_file_hash(unsigned int value)
+{
+ int match;
+ char *tracedata;
+
+ match = 0;
+ for (tracedata = &__tracedata_start ; tracedata < &__tracedata_end ;
+ tracedata += 2 + sizeof(unsigned long)) {
+ unsigned short lineno = *(unsigned short *)tracedata;
+ const char *file = *(const char **)(tracedata + 2);
+ unsigned int hash = hash_string(lineno, file, FILEHASH);
+ if (hash != value)
+ continue;
+ printk(" hash matches %s:%u\n", file, lineno);
+ match++;
+ }
+ return match;
+}
+
+static int show_dev_hash(unsigned int value)
+{
+ int match = 0;
+ struct list_head *entry = dpm_list.prev;
+
+ while (entry != &dpm_list) {
+ struct device * dev = to_device(entry);
+ unsigned int hash = hash_string(DEVSEED, dev->bus_id, DEVHASH);
+ if (hash == value) {
+ dev_info(dev, "hash matches\n");
+ match++;
+ }
+ entry = entry->prev;
+ }
+ return match;
+}
+
+static unsigned int hash_value_early_read;
+
+static int early_resume_init(void)
+{
+ hash_value_early_read = read_magic_time();
+ return 0;
+}
+
+static int late_resume_init(void)
+{
+ unsigned int val = hash_value_early_read;
+ unsigned int user, file, dev;
+
+ user = val % USERHASH;
+ val = val / USERHASH;
+ file = val % FILEHASH;
+ val = val / FILEHASH;
+ dev = val /* % DEVHASH */;
+
+ printk(" Magic number: %d:%d:%d\n", user, file, dev);
+ show_file_hash(file);
+ show_dev_hash(dev);
+ return 0;
+}
+
+core_initcall(early_resume_init);
+late_initcall(late_resume_init);
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