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Merge branch 'pm-runtime' into pm-for-linus 

* pm-runtime:
  PM / Runtime: Handle .runtime_suspend() failure correctly
  PM / Runtime: Fix kerneldoc comment for rpm_suspend()
  PM / Runtime: Update document about callbacks
This commit is contained in:
Rafael J. Wysocki 2011-10-16 23:26:49 +02:00
parent 7811ac276b 857b36c7b0
commit 9bd717c0dc
2 changed files with 30 additions and 22 deletions
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19
Documentation/power/runtime_pm.txt
View File

@ -43,13 +43,18 @@ struct dev_pm_ops {
...
};
The ->runtime_suspend(), ->runtime_resume() and ->runtime_idle() callbacks are
executed by the PM core for either the device type, or the class (if the device
type's struct dev_pm_ops object does not exist), or the bus type (if the
device type's and class' struct dev_pm_ops objects do not exist) of the given
device (this allows device types to override callbacks provided by bus types or
classes if necessary). The bus type, device type and class callbacks are
referred to as subsystem-level callbacks in what follows.
The ->runtime_suspend(), ->runtime_resume() and ->runtime_idle() callbacks
are executed by the PM core for either the power domain, or the device type
(if the device power domain's struct dev_pm_ops does not exist), or the class
(if the device power domain's and type's struct dev_pm_ops object does not
exist), or the bus type (if the device power domain's, type's and class'
struct dev_pm_ops objects do not exist) of the given device, so the priority
order of callbacks from high to low is that power domain callbacks, device
type callbacks, class callbacks and bus type callbacks, and the high priority
one will take precedence over low priority one. The bus type, device type and
class callbacks are referred to as subsystem-level callbacks in what follows,
and generally speaking, the power domain callbacks are used for representing
power domains within a SoC.
By default, the callbacks are always invoked in process context with interrupts
enabled. However, subsystems can use the pm_runtime_irq_safe() helper function

33
drivers/base/power/runtime.c
View File

@ -286,14 +286,16 @@ static int rpm_callback(int (*cb)(struct device *), struct device *dev)
* @dev: Device to suspend.
* @rpmflags: Flag bits.
*
* Check if the device's runtime PM status allows it to be suspended. If
* another suspend has been started earlier, either return immediately or wait
* for it to finish, depending on the RPM_NOWAIT and RPM_ASYNC flags. Cancel a
* pending idle notification. If the RPM_ASYNC flag is set then queue a
* suspend request; otherwise run the ->runtime_suspend() callback directly.
* If a deferred resume was requested while the callback was running then carry
* it out; otherwise send an idle notification for the device (if the suspend
* failed) or for its parent (if the suspend succeeded).
* Check if the device's runtime PM status allows it to be suspended.
* Cancel a pending idle notification, autosuspend or suspend. If
* another suspend has been started earlier, either return immediately
* or wait for it to finish, depending on the RPM_NOWAIT and RPM_ASYNC
* flags. If the RPM_ASYNC flag is set then queue a suspend request;
* otherwise run the ->runtime_suspend() callback directly. When
* ->runtime_suspend succeeded, if a deferred resume was requested while
* the callback was running then carry it out, otherwise send an idle
* notification for its parent (if the suspend succeeded and both
* ignore_children of parent->power and irq_safe of dev->power are not set).
*
* This function must be called under dev->power.lock with interrupts disabled.
*/
@ -418,15 +420,16 @@ static int rpm_suspend(struct device *dev, int rpmflags)
dev->power.runtime_error = 0;
else
pm_runtime_cancel_pending(dev);
} else {
wake_up_all(&dev->power.wait_queue);
goto out;
}
no_callback:
__update_runtime_status(dev, RPM_SUSPENDED);
pm_runtime_deactivate_timer(dev);
__update_runtime_status(dev, RPM_SUSPENDED);
pm_runtime_deactivate_timer(dev);
if (dev->parent) {
parent = dev->parent;
atomic_add_unless(&parent->power.child_count, -1, 0);
}
if (dev->parent) {
parent = dev->parent;
atomic_add_unless(&parent->power.child_count, -1, 0);
}
wake_up_all(&dev->power.wait_queue);