2  * Devices PM QoS constraints management
12  * per-device PM QoS dependencies. It provides infrastructure for registration
15  * Dependents on a QoS value : register requests
16  * Watchers of QoS value : get notified when target QoS value changes
18  * This QoS design is best effort based. Dependents register their QoS needs.
19  * Watchers register to keep track of the current QoS needs of the system.
50  * __dev_pm_qos_flags - Check PM QoS flags for a given device.
51  * @dev: Device to check the PM QoS flags for.
58 	struct dev_pm_qos *qos = dev->power.qos;  in __dev_pm_qos_flags()  local
64 	if (IS_ERR_OR_NULL(qos))  in __dev_pm_qos_flags()
67 	pqf = &qos->flags;  in __dev_pm_qos_flags()
79  * dev_pm_qos_flags - Check PM QoS flags for a given device (locked).
80  * @dev: Device to check the PM QoS flags for.
97  * __dev_pm_qos_read_value - Get PM QoS constraint for a given device.
98  * @dev: Device to get the PM QoS constraint value for.
110  * dev_pm_qos_read_value - Get PM QoS constraint for a given device (locked).
111  * @dev: Device to get the PM QoS constraint value for.
126  * apply_constraint - Add/modify/remove device PM QoS request.
129  * @value: Value to assign to the QoS request.
131  * Internal function to update the constraints list using the PM QoS core
137 	struct dev_pm_qos *qos = req->dev->power.qos;  in apply_constraint()  local
145 		ret = pm_qos_update_target(&qos->resume_latency,  in apply_constraint()
149 		ret = pm_qos_update_target(&qos->latency_tolerance,  in apply_constraint()
152 			value = pm_qos_read_value(&qos->latency_tolerance);  in apply_constraint()
157 		ret = pm_qos_update_flags(&qos->flags, &req->data.flr,  in apply_constraint()
176 	struct dev_pm_qos *qos;  in dev_pm_qos_constraints_allocate()  local
180 	qos = kzalloc(sizeof(*qos), GFP_KERNEL);  in dev_pm_qos_constraints_allocate()
181 	if (!qos)  in dev_pm_qos_constraints_allocate()
186 		kfree(qos);  in dev_pm_qos_constraints_allocate()
191 	c = &qos->resume_latency;  in dev_pm_qos_constraints_allocate()
199 	c = &qos->latency_tolerance;  in dev_pm_qos_constraints_allocate()
206 	INIT_LIST_HEAD(&qos->flags.list);  in dev_pm_qos_constraints_allocate()
209 	dev->power.qos = qos;  in dev_pm_qos_constraints_allocate()
226 	struct dev_pm_qos *qos;  in dev_pm_qos_constraints_destroy()  local
234 	 * If the device's PM QoS resume latency limit or PM QoS flags have been  in dev_pm_qos_constraints_destroy()
245 	qos = dev->power.qos;  in dev_pm_qos_constraints_destroy()
246 	if (!qos)  in dev_pm_qos_constraints_destroy()
250 	c = &qos->resume_latency;  in dev_pm_qos_constraints_destroy()
259 	c = &qos->latency_tolerance;  in dev_pm_qos_constraints_destroy()
264 	f = &qos->flags;  in dev_pm_qos_constraints_destroy()
271 	dev->power.qos = ERR_PTR(-ENODEV);  in dev_pm_qos_constraints_destroy()
274 	kfree(qos->resume_latency.notifiers);  in dev_pm_qos_constraints_destroy()
275 	kfree(qos);  in dev_pm_qos_constraints_destroy()
303 	if (IS_ERR(dev->power.qos))  in __dev_pm_qos_add_request()
305 	else if (!dev->power.qos)  in __dev_pm_qos_add_request()
318  * dev_pm_qos_add_request - inserts new qos request into the list
322  * @value: defines the qos request
325  * requested qos performance characteristics. It recomputes the aggregate
326  * QoS expectations of parameters and initializes the dev_pm_qos_request
352  * __dev_pm_qos_update_request - Modify an existing device PM QoS request.
353  * @req : PM QoS request to modify.
369 	if (IS_ERR_OR_NULL(req->dev->power.qos))  in __dev_pm_qos_update_request()
393  * dev_pm_qos_update_request - modifies an existing qos request
395  * @new_value: defines the qos request
397  * Updates an existing dev PM qos request along with updating the
432 	if (IS_ERR_OR_NULL(req->dev->power.qos))  in __dev_pm_qos_remove_request()
443  * dev_pm_qos_remove_request - modifies an existing qos request
446  * Will remove pm qos request from the list of constraints and
470  * of per-device PM QoS constraints
487 	if (IS_ERR(dev->power.qos))  in dev_pm_qos_add_notifier()
489 	else if (!dev->power.qos)  in dev_pm_qos_add_notifier()
493 		ret = blocking_notifier_chain_register(dev->power.qos->resume_latency.notifiers,  in dev_pm_qos_add_notifier()
503  * of per-device PM QoS constraints
519 	if (!IS_ERR_OR_NULL(dev->power.qos))  in dev_pm_qos_remove_notifier()
520 		retval = blocking_notifier_chain_unregister(dev->power.qos->resume_latency.notifiers,  in dev_pm_qos_remove_notifier()
529  * dev_pm_qos_add_ancestor_request - Add PM QoS request for device's ancestor.
573 		req = dev->power.qos->resume_latency_req;  in __dev_pm_qos_drop_user_request()
574 		dev->power.qos->resume_latency_req = NULL;  in __dev_pm_qos_drop_user_request()
577 		req = dev->power.qos->latency_tolerance_req;  in __dev_pm_qos_drop_user_request()
578 		dev->power.qos->latency_tolerance_req = NULL;  in __dev_pm_qos_drop_user_request()
581 		req = dev->power.qos->flags_req;  in __dev_pm_qos_drop_user_request()
582 		dev->power.qos->flags_req = NULL;  in __dev_pm_qos_drop_user_request()
598  * dev_pm_qos_expose_latency_limit - Expose PM QoS latency limit to user space.
599  * @dev: Device whose PM QoS latency limit is to be exposed to user space.
624 	if (IS_ERR_OR_NULL(dev->power.qos))  in dev_pm_qos_expose_latency_limit()
626 	else if (dev->power.qos->resume_latency_req)  in dev_pm_qos_expose_latency_limit()
635 	dev->power.qos->resume_latency_req = req;  in dev_pm_qos_expose_latency_limit()
651 	if (!IS_ERR_OR_NULL(dev->power.qos) && dev->power.qos->resume_latency_req)  in __dev_pm_qos_hide_latency_limit()
656  * dev_pm_qos_hide_latency_limit - Hide PM QoS latency limit from user space.
657  * @dev: Device whose PM QoS latency limit is to be hidden from user space.
674  * dev_pm_qos_expose_flags - Expose PM QoS flags of a device to user space.
675  * @dev: Device whose PM QoS flags are to be exposed to user space.
701 	if (IS_ERR_OR_NULL(dev->power.qos))  in dev_pm_qos_expose_flags()
703 	else if (dev->power.qos->flags_req)  in dev_pm_qos_expose_flags()
712 	dev->power.qos->flags_req = req;  in dev_pm_qos_expose_flags()
729 	if (!IS_ERR_OR_NULL(dev->power.qos) && dev->power.qos->flags_req)  in __dev_pm_qos_hide_flags()
734  * dev_pm_qos_hide_flags - Hide PM QoS flags of a device from user space.
735  * @dev: Device whose PM QoS flags are to be hidden from user space.
754  * dev_pm_qos_update_flags - Update PM QoS flags request owned by user space.
755  * @dev: Device to update the PM QoS flags request for.
767 	if (IS_ERR_OR_NULL(dev->power.qos) || !dev->power.qos->flags_req) {  in dev_pm_qos_update_flags()
778 	ret = __dev_pm_qos_update_request(dev->power.qos->flags_req, value);  in dev_pm_qos_update_flags()
795 	ret = IS_ERR_OR_NULL(dev->power.qos)  in dev_pm_qos_get_user_latency_tolerance()
796 		|| !dev->power.qos->latency_tolerance_req ?  in dev_pm_qos_get_user_latency_tolerance()
798 			dev->power.qos->latency_tolerance_req->data.pnode.prio;  in dev_pm_qos_get_user_latency_tolerance()
814 	if (IS_ERR_OR_NULL(dev->power.qos)  in dev_pm_qos_update_user_latency_tolerance()
815 	    || !dev->power.qos->latency_tolerance_req) {  in dev_pm_qos_update_user_latency_tolerance()
835 		dev->power.qos->latency_tolerance_req = req;  in dev_pm_qos_update_user_latency_tolerance()
841 			ret = __dev_pm_qos_update_request(dev->power.qos->latency_tolerance_req, val);  in dev_pm_qos_update_user_latency_tolerance()