*/
LIST_HEAD(dpm_active);
-static LIST_HEAD(dpm_locked);
static LIST_HEAD(dpm_off);
static LIST_HEAD(dpm_off_irq);
-static LIST_HEAD(dpm_destroy);
static DEFINE_MUTEX(dpm_list_mtx);
-static DECLARE_RWSEM(pm_sleep_rwsem);
-
-int (*platform_enable_wakeup)(struct device *dev, int is_on);
+/* 'true' if all devices have been suspended, protected by dpm_list_mtx */
+static bool all_sleeping;
/**
* 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)
+int device_pm_add(struct device *dev)
{
+ int error;
+
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);
- list_add_tail(&dev->power.entry, &dpm_active);
+ if ((dev->parent && dev->parent->power.sleeping) || all_sleeping) {
+ if (dev->parent->power.sleeping)
+ dev_warn(dev, "parent %s is sleeping\n",
+ dev->parent->bus_id);
+ else
+ dev_warn(dev, "all devices are sleeping\n");
+ WARN_ON(true);
+ }
+ error = dpm_sysfs_add(dev);
+ if (!error)
+ list_add_tail(&dev->power.entry, &dpm_active);
mutex_unlock(&dpm_list_mtx);
+ return error;
}
/**
*/
void device_pm_remove(struct device *dev)
{
- /*
- * If this function is called during a suspend, it will be blocked,
- * because we're holding the device's semaphore at that time, which may
- * lead to a deadlock. In that case we want to print a warning.
- * However, it may also be called by unregister_dropped_devices() with
- * the device's semaphore released, in which case the warning should
- * not be printed.
- */
- if (down_trylock(&dev->sem)) {
- if (down_read_trylock(&pm_sleep_rwsem)) {
- /* No suspend in progress, wait on dev->sem */
- down(&dev->sem);
- up_read(&pm_sleep_rwsem);
- } else {
- /* Suspend in progress, we may deadlock */
- dev_warn(dev, "Suspicious %s during suspend\n",
- __FUNCTION__);
- dump_stack();
- /* The user has been warned ... */
- down(&dev->sem);
- }
- }
pr_debug("PM: Removing info for %s:%s\n",
dev->bus ? dev->bus->name : "No Bus",
kobject_name(&dev->kobj));
dpm_sysfs_remove(dev);
list_del_init(&dev->power.entry);
mutex_unlock(&dpm_list_mtx);
- up(&dev->sem);
-}
-
-/**
- * device_pm_schedule_removal - schedule the removal of a suspended device
- * @dev: Device to destroy
- *
- * Moves the device to the dpm_destroy list for further processing by
- * unregister_dropped_devices().
- */
-void device_pm_schedule_removal(struct device *dev)
-{
- pr_debug("PM: Preparing for removal: %s:%s\n",
- dev->bus ? dev->bus->name : "No Bus",
- kobject_name(&dev->kobj));
- mutex_lock(&dpm_list_mtx);
- list_move_tail(&dev->power.entry, &dpm_destroy);
- mutex_unlock(&dpm_list_mtx);
-}
-EXPORT_SYMBOL_GPL(device_pm_schedule_removal);
-
-/**
- * pm_sleep_lock - mutual exclusion for registration and suspend
- *
- * Returns 0 if no suspend is underway and device registration
- * may proceed, otherwise -EBUSY.
- */
-int pm_sleep_lock(void)
-{
- if (down_read_trylock(&pm_sleep_rwsem))
- return 0;
-
- return -EBUSY;
}
-/**
- * pm_sleep_unlock - mutual exclusion for registration and suspend
- *
- * This routine undoes the effect of device_pm_add_lock
- * when a device's registration is complete.
- */
-void pm_sleep_unlock(void)
-{
- up_read(&pm_sleep_rwsem);
-}
-
-
/*------------------------- Resume routines -------------------------*/
/**
TRACE_DEVICE(dev);
TRACE_RESUME(0);
+ down(&dev->sem);
+
if (dev->bus && dev->bus->resume) {
dev_dbg(dev,"resuming\n");
error = dev->bus->resume(dev);
error = dev->class->resume(dev);
}
+ up(&dev->sem);
+
TRACE_RESUME(error);
return error;
}
static void dpm_resume(void)
{
mutex_lock(&dpm_list_mtx);
+ all_sleeping = false;
while(!list_empty(&dpm_off)) {
struct list_head *entry = dpm_off.next;
struct device *dev = to_device(entry);
- list_move_tail(entry, &dpm_locked);
+ list_move_tail(entry, &dpm_active);
+ dev->power.sleeping = false;
mutex_unlock(&dpm_list_mtx);
resume_device(dev);
mutex_lock(&dpm_list_mtx);
mutex_unlock(&dpm_list_mtx);
}
-/**
- * unlock_all_devices - Release each device's semaphore
- *
- * Go through the dpm_off list. Put each device on the dpm_active
- * list and unlock it.
- */
-static void unlock_all_devices(void)
-{
- mutex_lock(&dpm_list_mtx);
- while (!list_empty(&dpm_locked)) {
- struct list_head *entry = dpm_locked.prev;
- struct device *dev = to_device(entry);
-
- list_move(entry, &dpm_active);
- up(&dev->sem);
- }
- mutex_unlock(&dpm_list_mtx);
-}
-
-/**
- * unregister_dropped_devices - Unregister devices scheduled for removal
- *
- * Unregister all devices on the dpm_destroy list.
- */
-static void unregister_dropped_devices(void)
-{
- mutex_lock(&dpm_list_mtx);
- while (!list_empty(&dpm_destroy)) {
- struct list_head *entry = dpm_destroy.next;
- struct device *dev = to_device(entry);
-
- up(&dev->sem);
- mutex_unlock(&dpm_list_mtx);
- /* This also removes the device from the list */
- device_unregister(dev);
- mutex_lock(&dpm_list_mtx);
- }
- mutex_unlock(&dpm_list_mtx);
-}
-
/**
* device_resume - Restore state of each device in system.
*
{
might_sleep();
dpm_resume();
- unlock_all_devices();
- unregister_dropped_devices();
- up_write(&pm_sleep_rwsem);
}
EXPORT_SYMBOL_GPL(device_resume);
struct list_head *entry = dpm_off.prev;
struct device *dev = to_device(entry);
- list_del_init(&dev->power.entry);
error = suspend_device_late(dev, state);
if (error) {
printk(KERN_ERR "Could not power down device %s: "
"error %d\n",
kobject_name(&dev->kobj), error);
- if (list_empty(&dev->power.entry))
- list_add(&dev->power.entry, &dpm_off);
break;
}
- if (list_empty(&dev->power.entry))
- list_add(&dev->power.entry, &dpm_off_irq);
+ if (!list_empty(&dev->power.entry))
+ list_move(&dev->power.entry, &dpm_off_irq);
}
if (!error)
{
int error = 0;
- if (dev->power.power_state.event) {
- dev_dbg(dev, "PM: suspend %d-->%d\n",
- dev->power.power_state.event, state.event);
- }
+ down(&dev->sem);
if (dev->class && dev->class->suspend) {
suspend_device_dbg(dev, state, "class ");
error = dev->bus->suspend(dev, state);
suspend_report_result(dev->bus->suspend, error);
}
+
+ up(&dev->sem);
+
return error;
}
int error = 0;
mutex_lock(&dpm_list_mtx);
- while (!list_empty(&dpm_locked)) {
- struct list_head *entry = dpm_locked.prev;
+ while (!list_empty(&dpm_active)) {
+ struct list_head *entry = dpm_active.prev;
struct device *dev = to_device(entry);
- list_del_init(&dev->power.entry);
+ WARN_ON(dev->parent && dev->parent->power.sleeping);
+
+ dev->power.sleeping = true;
mutex_unlock(&dpm_list_mtx);
error = suspend_device(dev, state);
+ mutex_lock(&dpm_list_mtx);
if (error) {
printk(KERN_ERR "Could not suspend device %s: "
"error %d%s\n",
(error == -EAGAIN ?
" (please convert to suspend_late)" :
""));
- mutex_lock(&dpm_list_mtx);
- if (list_empty(&dev->power.entry))
- list_add(&dev->power.entry, &dpm_locked);
+ dev->power.sleeping = false;
break;
}
- mutex_lock(&dpm_list_mtx);
- if (list_empty(&dev->power.entry))
- list_add(&dev->power.entry, &dpm_off);
+ if (!list_empty(&dev->power.entry))
+ list_move(&dev->power.entry, &dpm_off);
}
+ if (!error)
+ all_sleeping = true;
mutex_unlock(&dpm_list_mtx);
return error;
}
-/**
- * lock_all_devices - Acquire every device's semaphore
- *
- * Go through the dpm_active list. Carefully lock each device's
- * semaphore and put it in on the dpm_locked list.
- */
-static void lock_all_devices(void)
-{
- mutex_lock(&dpm_list_mtx);
- while (!list_empty(&dpm_active)) {
- struct list_head *entry = dpm_active.next;
- struct device *dev = to_device(entry);
-
- /* Required locking order is dev->sem first,
- * then dpm_list_mutex. Hence this awkward code.
- */
- get_device(dev);
- mutex_unlock(&dpm_list_mtx);
- down(&dev->sem);
- mutex_lock(&dpm_list_mtx);
-
- if (list_empty(entry))
- up(&dev->sem); /* Device was removed */
- else
- list_move_tail(entry, &dpm_locked);
- put_device(dev);
- }
- mutex_unlock(&dpm_list_mtx);
-}
-
/**
* device_suspend - Save state and stop all devices in system.
* @state: new power management state
int error;
might_sleep();
- down_write(&pm_sleep_rwsem);
- lock_all_devices();
error = dpm_suspend(state);
if (error)
device_resume();
git.samba.org / sfrench / cifs-2.6.git / blobdiff