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-rw-r--r--drivers/base/power/main.c784
1 files changed, 784 insertions, 0 deletions
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);
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