under the device's power directory.
Notification mechanisms:
-The per-device PM QoS framework has 2 different and distinct notification trees:
-a per-device notification tree and a global notification tree.
+The per-device PM QoS framework has a per-device notification tree.
int dev_pm_qos_add_notifier(device, notifier):
Adds a notification callback function for the device.
int dev_pm_qos_remove_notifier(device, notifier):
Removes the notification callback function for the device.
-int dev_pm_qos_add_global_notifier(notifier):
-Adds a notification callback function in the global notification tree of the
-framework.
-The callback is called when the aggregated value for any device is changed
-(for resume latency device PM QoS only).
-
-int dev_pm_qos_remove_global_notifier(notifier):
-Removes the notification callback function from the global notification tree
-of the framework.
-
Active state latency tolerance
*
* This QoS design is best effort based. Dependents register their QoS needs.
* Watchers register to keep track of the current QoS needs of the system.
- * Watchers can register different types of notification callbacks:
- * . a per-device notification callback using the dev_pm_qos_*_notifier API.
- * The notification chain data is stored in the per-device constraint
- * data struct.
- * . a system-wide notification callback using the dev_pm_qos_*_global_notifier
- * API. The notification chain data is stored in a static variable.
+ * Watchers can register a per-device notification callback using the
+ * dev_pm_qos_*_notifier API. The notification chain data is stored in the
+ * per-device constraint data struct.
*
* Note about the per-device constraint data struct allocation:
* . The per-device constraints data struct ptr is tored into the device
static DEFINE_MUTEX(dev_pm_qos_mtx);
static DEFINE_MUTEX(dev_pm_qos_sysfs_mtx);
-static BLOCKING_NOTIFIER_HEAD(dev_pm_notifiers);
-
/**
* __dev_pm_qos_flags - Check PM QoS flags for a given device.
* @dev: Device to check the PM QoS flags for.
* @value: Value to assign to the QoS request.
*
* Internal function to update the constraints list using the PM QoS core
- * code and if needed call the per-device and the global notification
- * callbacks
+ * code and if needed call the per-device callbacks.
*/
static int apply_constraint(struct dev_pm_qos_request *req,
enum pm_qos_req_action action, s32 value)
case DEV_PM_QOS_RESUME_LATENCY:
ret = pm_qos_update_target(&qos->resume_latency,
&req->data.pnode, action, value);
- if (ret) {
- value = pm_qos_read_value(&qos->resume_latency);
- blocking_notifier_call_chain(&dev_pm_notifiers,
- (unsigned long)value,
- req);
- }
break;
case DEV_PM_QOS_LATENCY_TOLERANCE:
ret = pm_qos_update_target(&qos->latency_tolerance,
EXPORT_SYMBOL_GPL(dev_pm_qos_remove_notifier);
/**
- * dev_pm_qos_add_global_notifier - sets notification entry for changes to
- * target value of the PM QoS constraints for any device
- *
- * @notifier: notifier block managed by caller.
- *
- * Will register the notifier into a notification chain that gets called
- * upon changes to the target value for any device.
- */
-int dev_pm_qos_add_global_notifier(struct notifier_block *notifier)
-{
- return blocking_notifier_chain_register(&dev_pm_notifiers, notifier);
-}
-EXPORT_SYMBOL_GPL(dev_pm_qos_add_global_notifier);
-
-/**
- * dev_pm_qos_remove_global_notifier - deletes notification for changes to
- * target value of PM QoS constraints for any device
- *
- * @notifier: notifier block to be removed.
- *
- * Will remove the notifier from the notification chain that gets called
- * upon changes to the target value for any device.
- */
-int dev_pm_qos_remove_global_notifier(struct notifier_block *notifier)
-{
- return blocking_notifier_chain_unregister(&dev_pm_notifiers, notifier);
-}
-EXPORT_SYMBOL_GPL(dev_pm_qos_remove_global_notifier);
-
-/**
* dev_pm_qos_add_ancestor_request - Add PM QoS request for device's ancestor.
* @dev: Device whose ancestor to add the request for.
* @req: Pointer to the preallocated handle.
struct notifier_block *notifier);
int dev_pm_qos_remove_notifier(struct device *dev,
struct notifier_block *notifier);
-int dev_pm_qos_add_global_notifier(struct notifier_block *notifier);
-int dev_pm_qos_remove_global_notifier(struct notifier_block *notifier);
void dev_pm_qos_constraints_init(struct device *dev);
void dev_pm_qos_constraints_destroy(struct device *dev);
int dev_pm_qos_add_ancestor_request(struct device *dev,
static inline int dev_pm_qos_remove_notifier(struct device *dev,
struct notifier_block *notifier)
{ return 0; }
-static inline int dev_pm_qos_add_global_notifier(
- struct notifier_block *notifier)
- { return 0; }
-static inline int dev_pm_qos_remove_global_notifier(
- struct notifier_block *notifier)
- { return 0; }
static inline void dev_pm_qos_constraints_init(struct device *dev)
{
dev->power.power_state = PMSG_ON;