| /* |
| * Devices PM QoS constraints management |
| * |
| * Copyright (C) 2011 Texas Instruments, Inc. |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2 as |
| * published by the Free Software Foundation. |
| * |
| * |
| * This module exposes the interface to kernel space for specifying |
| * per-device PM QoS dependencies. It provides infrastructure for registration |
| * of: |
| * |
| * Dependents on a QoS value : register requests |
| * Watchers of QoS value : get notified when target QoS value changes |
| * |
| * 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. |
| * |
| * Note about the per-device constraint data struct allocation: |
| * . The per-device constraints data struct ptr is tored into the device |
| * dev_pm_info. |
| * . To minimize the data usage by the per-device constraints, the data struct |
| * is only allocated at the first call to dev_pm_qos_add_request. |
| * . The data is later free'd when the device is removed from the system. |
| * . A global mutex protects the constraints users from the data being |
| * allocated and free'd. |
| */ |
| |
| #include <linux/pm_qos.h> |
| #include <linux/spinlock.h> |
| #include <linux/slab.h> |
| #include <linux/device.h> |
| #include <linux/mutex.h> |
| #include <linux/export.h> |
| #include <linux/pm_runtime.h> |
| #include <linux/err.h> |
| #include <trace/events/power.h> |
| |
| #include "power.h" |
| |
| 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. |
| * @mask: Flags to check against. |
| * |
| * This routine must be called with dev->power.lock held. |
| */ |
| enum pm_qos_flags_status __dev_pm_qos_flags(struct device *dev, s32 mask) |
| { |
| struct dev_pm_qos *qos = dev->power.qos; |
| struct pm_qos_flags *pqf; |
| s32 val; |
| |
| lockdep_assert_held(&dev->power.lock); |
| |
| if (IS_ERR_OR_NULL(qos)) |
| return PM_QOS_FLAGS_UNDEFINED; |
| |
| pqf = &qos->flags; |
| if (list_empty(&pqf->list)) |
| return PM_QOS_FLAGS_UNDEFINED; |
| |
| val = pqf->effective_flags & mask; |
| if (val) |
| return (val == mask) ? PM_QOS_FLAGS_ALL : PM_QOS_FLAGS_SOME; |
| |
| return PM_QOS_FLAGS_NONE; |
| } |
| |
| /** |
| * dev_pm_qos_flags - Check PM QoS flags for a given device (locked). |
| * @dev: Device to check the PM QoS flags for. |
| * @mask: Flags to check against. |
| */ |
| enum pm_qos_flags_status dev_pm_qos_flags(struct device *dev, s32 mask) |
| { |
| unsigned long irqflags; |
| enum pm_qos_flags_status ret; |
| |
| spin_lock_irqsave(&dev->power.lock, irqflags); |
| ret = __dev_pm_qos_flags(dev, mask); |
| spin_unlock_irqrestore(&dev->power.lock, irqflags); |
| |
| return ret; |
| } |
| EXPORT_SYMBOL_GPL(dev_pm_qos_flags); |
| |
| /** |
| * __dev_pm_qos_read_value - Get PM QoS constraint for a given device. |
| * @dev: Device to get the PM QoS constraint value for. |
| * |
| * This routine must be called with dev->power.lock held. |
| */ |
| s32 __dev_pm_qos_read_value(struct device *dev) |
| { |
| lockdep_assert_held(&dev->power.lock); |
| |
| return IS_ERR_OR_NULL(dev->power.qos) ? |
| 0 : pm_qos_read_value(&dev->power.qos->resume_latency); |
| } |
| |
| /** |
| * dev_pm_qos_read_value - Get PM QoS constraint for a given device (locked). |
| * @dev: Device to get the PM QoS constraint value for. |
| */ |
| s32 dev_pm_qos_read_value(struct device *dev) |
| { |
| unsigned long flags; |
| s32 ret; |
| |
| spin_lock_irqsave(&dev->power.lock, flags); |
| ret = __dev_pm_qos_read_value(dev); |
| spin_unlock_irqrestore(&dev->power.lock, flags); |
| |
| return ret; |
| } |
| |
| /** |
| * apply_constraint - Add/modify/remove device PM QoS request. |
| * @req: Constraint request to apply |
| * @action: Action to perform (add/update/remove). |
| * @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 |
| */ |
| static int apply_constraint(struct dev_pm_qos_request *req, |
| enum pm_qos_req_action action, s32 value) |
| { |
| struct dev_pm_qos *qos = req->dev->power.qos; |
| int ret; |
| |
| switch(req->type) { |
| case DEV_PM_QOS_RESUME_LATENCY: |
| ret = pm_qos_update_target(&qos->resume_latency, |
| &req->data.lat, 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, |
| &req->data.lat, action, value); |
| if (ret) { |
| value = pm_qos_read_value(&qos->latency_tolerance); |
| req->dev->power.set_latency_tolerance(req->dev, value); |
| } |
| break; |
| case DEV_PM_QOS_FLAGS: |
| ret = pm_qos_update_flags(&qos->flags, &req->data.flr, |
| action, value); |
| break; |
| default: |
| ret = -EINVAL; |
| } |
| |
| return ret; |
| } |
| |
| /* |
| * dev_pm_qos_constraints_allocate |
| * @dev: device to allocate data for |
| * |
| * Called at the first call to add_request, for constraint data allocation |
| * Must be called with the dev_pm_qos_mtx mutex held |
| */ |
| static int dev_pm_qos_constraints_allocate(struct device *dev) |
| { |
| struct dev_pm_qos *qos; |
| struct pm_qos_constraints *c; |
| struct blocking_notifier_head *n; |
| |
| qos = kzalloc(sizeof(*qos), GFP_KERNEL); |
| if (!qos) |
| return -ENOMEM; |
| |
| n = kzalloc(sizeof(*n), GFP_KERNEL); |
| if (!n) { |
| kfree(qos); |
| return -ENOMEM; |
| } |
| BLOCKING_INIT_NOTIFIER_HEAD(n); |
| |
| c = &qos->resume_latency; |
| plist_head_init(&c->list); |
| c->target_value = PM_QOS_RESUME_LATENCY_DEFAULT_VALUE; |
| c->default_value = PM_QOS_RESUME_LATENCY_DEFAULT_VALUE; |
| c->no_constraint_value = PM_QOS_RESUME_LATENCY_DEFAULT_VALUE; |
| c->type = PM_QOS_MIN; |
| c->notifiers = n; |
| |
| c = &qos->latency_tolerance; |
| plist_head_init(&c->list); |
| c->target_value = PM_QOS_LATENCY_TOLERANCE_DEFAULT_VALUE; |
| c->default_value = PM_QOS_LATENCY_TOLERANCE_DEFAULT_VALUE; |
| c->no_constraint_value = PM_QOS_LATENCY_TOLERANCE_NO_CONSTRAINT; |
| c->type = PM_QOS_MIN; |
| |
| INIT_LIST_HEAD(&qos->flags.list); |
| |
| spin_lock_irq(&dev->power.lock); |
| dev->power.qos = qos; |
| spin_unlock_irq(&dev->power.lock); |
| |
| return 0; |
| } |
| |
| static void __dev_pm_qos_hide_latency_limit(struct device *dev); |
| static void __dev_pm_qos_hide_flags(struct device *dev); |
| |
| /** |
| * dev_pm_qos_constraints_destroy |
| * @dev: target device |
| * |
| * Called from the device PM subsystem on device removal under device_pm_lock(). |
| */ |
| void dev_pm_qos_constraints_destroy(struct device *dev) |
| { |
| struct dev_pm_qos *qos; |
| struct dev_pm_qos_request *req, *tmp; |
| struct pm_qos_constraints *c; |
| struct pm_qos_flags *f; |
| |
| mutex_lock(&dev_pm_qos_sysfs_mtx); |
| |
| /* |
| * If the device's PM QoS resume latency limit or PM QoS flags have been |
| * exposed to user space, they have to be hidden at this point. |
| */ |
| pm_qos_sysfs_remove_resume_latency(dev); |
| pm_qos_sysfs_remove_flags(dev); |
| |
| mutex_lock(&dev_pm_qos_mtx); |
| |
| __dev_pm_qos_hide_latency_limit(dev); |
| __dev_pm_qos_hide_flags(dev); |
| |
| qos = dev->power.qos; |
| if (!qos) |
| goto out; |
| |
| /* Flush the constraints lists for the device. */ |
| c = &qos->resume_latency; |
| plist_for_each_entry_safe(req, tmp, &c->list, data.lat.node) { |
| /* |
| * Update constraints list and call the notification |
| * callbacks if needed |
| */ |
| apply_constraint(req, PM_QOS_REMOVE_REQ, PM_QOS_DEFAULT_VALUE); |
| memset(req, 0, sizeof(*req)); |
| } |
| c = &qos->latency_tolerance; |
| plist_for_each_entry_safe(req, tmp, &c->list, data.lat.node) { |
| apply_constraint(req, PM_QOS_REMOVE_REQ, PM_QOS_DEFAULT_VALUE); |
| memset(req, 0, sizeof(*req)); |
| } |
| f = &qos->flags; |
| list_for_each_entry_safe(req, tmp, &f->list, data.flr.node) { |
| apply_constraint(req, PM_QOS_REMOVE_REQ, PM_QOS_DEFAULT_VALUE); |
| memset(req, 0, sizeof(*req)); |
| } |
| |
| spin_lock_irq(&dev->power.lock); |
| dev->power.qos = ERR_PTR(-ENODEV); |
| spin_unlock_irq(&dev->power.lock); |
| |
| kfree(c->notifiers); |
| kfree(qos); |
| |
| out: |
| mutex_unlock(&dev_pm_qos_mtx); |
| |
| mutex_unlock(&dev_pm_qos_sysfs_mtx); |
| } |
| |
| static bool dev_pm_qos_invalid_request(struct device *dev, |
| struct dev_pm_qos_request *req) |
| { |
| return !req || (req->type == DEV_PM_QOS_LATENCY_TOLERANCE |
| && !dev->power.set_latency_tolerance); |
| } |
| |
| static int __dev_pm_qos_add_request(struct device *dev, |
| struct dev_pm_qos_request *req, |
| enum dev_pm_qos_req_type type, s32 value) |
| { |
| int ret = 0; |
| |
| if (!dev || dev_pm_qos_invalid_request(dev, req)) |
| return -EINVAL; |
| |
| if (WARN(dev_pm_qos_request_active(req), |
| "%s() called for already added request\n", __func__)) |
| return -EINVAL; |
| |
| if (IS_ERR(dev->power.qos)) |
| ret = -ENODEV; |
| else if (!dev->power.qos) |
| ret = dev_pm_qos_constraints_allocate(dev); |
| |
| trace_dev_pm_qos_add_request(dev_name(dev), type, value); |
| if (!ret) { |
| req->dev = dev; |
| req->type = type; |
| ret = apply_constraint(req, PM_QOS_ADD_REQ, value); |
| } |
| return ret; |
| } |
| |
| /** |
| * dev_pm_qos_add_request - inserts new qos request into the list |
| * @dev: target device for the constraint |
| * @req: pointer to a preallocated handle |
| * @type: type of the request |
| * @value: defines the qos request |
| * |
| * This function inserts a new entry in the device constraints list of |
| * requested qos performance characteristics. It recomputes the aggregate |
| * QoS expectations of parameters and initializes the dev_pm_qos_request |
| * handle. Caller needs to save this handle for later use in updates and |
| * removal. |
| * |
| * Returns 1 if the aggregated constraint value has changed, |
| * 0 if the aggregated constraint value has not changed, |
| * -EINVAL in case of wrong parameters, -ENOMEM if there's not enough memory |
| * to allocate for data structures, -ENODEV if the device has just been removed |
| * from the system. |
| * |
| * Callers should ensure that the target device is not RPM_SUSPENDED before |
| * using this function for requests of type DEV_PM_QOS_FLAGS. |
| */ |
| int dev_pm_qos_add_request(struct device *dev, struct dev_pm_qos_request *req, |
| enum dev_pm_qos_req_type type, s32 value) |
| { |
| int ret; |
| |
| mutex_lock(&dev_pm_qos_mtx); |
| ret = __dev_pm_qos_add_request(dev, req, type, value); |
| mutex_unlock(&dev_pm_qos_mtx); |
| return ret; |
| } |
| EXPORT_SYMBOL_GPL(dev_pm_qos_add_request); |
| |
| /** |
| * __dev_pm_qos_update_request - Modify an existing device PM QoS request. |
| * @req : PM QoS request to modify. |
| * @new_value: New value to request. |
| */ |
| static int __dev_pm_qos_update_request(struct dev_pm_qos_request *req, |
| s32 new_value) |
| { |
| s32 curr_value; |
| int ret = 0; |
| |
| if (!req) /*guard against callers passing in null */ |
| return -EINVAL; |
| |
| if (WARN(!dev_pm_qos_request_active(req), |
| "%s() called for unknown object\n", __func__)) |
| return -EINVAL; |
| |
| if (IS_ERR_OR_NULL(req->dev->power.qos)) |
| return -ENODEV; |
| |
| switch(req->type) { |
| case DEV_PM_QOS_RESUME_LATENCY: |
| case DEV_PM_QOS_LATENCY_TOLERANCE: |
| curr_value = req->data.lat.node.prio; |
| break; |
| case DEV_PM_QOS_FLAGS: |
| curr_value = req->data.flr.flags; |
| break; |
| default: |
| return -EINVAL; |
| } |
| |
| trace_dev_pm_qos_update_request(dev_name(req->dev), req->type, |
| new_value); |
| if (curr_value != new_value) |
| ret = apply_constraint(req, PM_QOS_UPDATE_REQ, new_value); |
| |
| return ret; |
| } |
| |
| /** |
| * dev_pm_qos_update_request - modifies an existing qos request |
| * @req : handle to list element holding a dev_pm_qos request to use |
| * @new_value: defines the qos request |
| * |
| * Updates an existing dev PM qos request along with updating the |
| * target value. |
| * |
| * Attempts are made to make this code callable on hot code paths. |
| * |
| * Returns 1 if the aggregated constraint value has changed, |
| * 0 if the aggregated constraint value has not changed, |
| * -EINVAL in case of wrong parameters, -ENODEV if the device has been |
| * removed from the system |
| * |
| * Callers should ensure that the target device is not RPM_SUSPENDED before |
| * using this function for requests of type DEV_PM_QOS_FLAGS. |
| */ |
| int dev_pm_qos_update_request(struct dev_pm_qos_request *req, s32 new_value) |
| { |
| int ret; |
| |
| mutex_lock(&dev_pm_qos_mtx); |
| ret = __dev_pm_qos_update_request(req, new_value); |
| mutex_unlock(&dev_pm_qos_mtx); |
| return ret; |
| } |
| EXPORT_SYMBOL_GPL(dev_pm_qos_update_request); |
| |
| static int __dev_pm_qos_remove_request(struct dev_pm_qos_request *req) |
| { |
| int ret; |
| |
| if (!req) /*guard against callers passing in null */ |
| return -EINVAL; |
| |
| if (WARN(!dev_pm_qos_request_active(req), |
| "%s() called for unknown object\n", __func__)) |
| return -EINVAL; |
| |
| if (IS_ERR_OR_NULL(req->dev->power.qos)) |
| return -ENODEV; |
| |
| trace_dev_pm_qos_remove_request(dev_name(req->dev), req->type, |
| PM_QOS_DEFAULT_VALUE); |
| ret = apply_constraint(req, PM_QOS_REMOVE_REQ, PM_QOS_DEFAULT_VALUE); |
| memset(req, 0, sizeof(*req)); |
| return ret; |
| } |
| |
| /** |
| * dev_pm_qos_remove_request - modifies an existing qos request |
| * @req: handle to request list element |
| * |
| * Will remove pm qos request from the list of constraints and |
| * recompute the current target value. Call this on slow code paths. |
| * |
| * Returns 1 if the aggregated constraint value has changed, |
| * 0 if the aggregated constraint value has not changed, |
| * -EINVAL in case of wrong parameters, -ENODEV if the device has been |
| * removed from the system |
| * |
| * Callers should ensure that the target device is not RPM_SUSPENDED before |
| * using this function for requests of type DEV_PM_QOS_FLAGS. |
| */ |
| int dev_pm_qos_remove_request(struct dev_pm_qos_request *req) |
| { |
| int ret; |
| |
| mutex_lock(&dev_pm_qos_mtx); |
| ret = __dev_pm_qos_remove_request(req); |
| mutex_unlock(&dev_pm_qos_mtx); |
| return ret; |
| } |
| EXPORT_SYMBOL_GPL(dev_pm_qos_remove_request); |
| |
| /** |
| * dev_pm_qos_add_notifier - sets notification entry for changes to target value |
| * of per-device PM QoS constraints |
| * |
| * @dev: target device for the constraint |
| * @notifier: notifier block managed by caller. |
| * |
| * Will register the notifier into a notification chain that gets called |
| * upon changes to the target value for the device. |
| * |
| * If the device's constraints object doesn't exist when this routine is called, |
| * it will be created (or error code will be returned if that fails). |
| */ |
| int dev_pm_qos_add_notifier(struct device *dev, struct notifier_block *notifier) |
| { |
| int ret = 0; |
| |
| mutex_lock(&dev_pm_qos_mtx); |
| |
| if (IS_ERR(dev->power.qos)) |
| ret = -ENODEV; |
| else if (!dev->power.qos) |
| ret = dev_pm_qos_constraints_allocate(dev); |
| |
| if (!ret) |
| ret = blocking_notifier_chain_register(dev->power.qos->resume_latency.notifiers, |
| notifier); |
| |
| mutex_unlock(&dev_pm_qos_mtx); |
| return ret; |
| } |
| EXPORT_SYMBOL_GPL(dev_pm_qos_add_notifier); |
| |
| /** |
| * dev_pm_qos_remove_notifier - deletes notification for changes to target value |
| * of per-device PM QoS constraints |
| * |
| * @dev: target device for the constraint |
| * @notifier: notifier block to be removed. |
| * |
| * Will remove the notifier from the notification chain that gets called |
| * upon changes to the target value. |
| */ |
| int dev_pm_qos_remove_notifier(struct device *dev, |
| struct notifier_block *notifier) |
| { |
| int retval = 0; |
| |
| mutex_lock(&dev_pm_qos_mtx); |
| |
| /* Silently return if the constraints object is not present. */ |
| if (!IS_ERR_OR_NULL(dev->power.qos)) |
| retval = blocking_notifier_chain_unregister(dev->power.qos->resume_latency.notifiers, |
| notifier); |
| |
| mutex_unlock(&dev_pm_qos_mtx); |
| return retval; |
| } |
| 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. |
| * @type: Type of the request. |
| * @value: Constraint latency value. |
| */ |
| int dev_pm_qos_add_ancestor_request(struct device *dev, |
| struct dev_pm_qos_request *req, |
| enum dev_pm_qos_req_type type, s32 value) |
| { |
| struct device *ancestor = dev->parent; |
| int ret = -ENODEV; |
| |
| switch (type) { |
| case DEV_PM_QOS_RESUME_LATENCY: |
| while (ancestor && !ancestor->power.ignore_children) |
| ancestor = ancestor->parent; |
| |
| break; |
| case DEV_PM_QOS_LATENCY_TOLERANCE: |
| while (ancestor && !ancestor->power.set_latency_tolerance) |
| ancestor = ancestor->parent; |
| |
| break; |
| default: |
| ancestor = NULL; |
| } |
| if (ancestor) |
| ret = dev_pm_qos_add_request(ancestor, req, type, value); |
| |
| if (ret < 0) |
| req->dev = NULL; |
| |
| return ret; |
| } |
| EXPORT_SYMBOL_GPL(dev_pm_qos_add_ancestor_request); |
| |
| static void __dev_pm_qos_drop_user_request(struct device *dev, |
| enum dev_pm_qos_req_type type) |
| { |
| struct dev_pm_qos_request *req = NULL; |
| |
| switch(type) { |
| case DEV_PM_QOS_RESUME_LATENCY: |
| req = dev->power.qos->resume_latency_req; |
| dev->power.qos->resume_latency_req = NULL; |
| break; |
| case DEV_PM_QOS_LATENCY_TOLERANCE: |
| req = dev->power.qos->latency_tolerance_req; |
| dev->power.qos->latency_tolerance_req = NULL; |
| break; |
| case DEV_PM_QOS_FLAGS: |
| req = dev->power.qos->flags_req; |
| dev->power.qos->flags_req = NULL; |
| break; |
| } |
| __dev_pm_qos_remove_request(req); |
| kfree(req); |
| } |
| |
| static void dev_pm_qos_drop_user_request(struct device *dev, |
| enum dev_pm_qos_req_type type) |
| { |
| mutex_lock(&dev_pm_qos_mtx); |
| __dev_pm_qos_drop_user_request(dev, type); |
| mutex_unlock(&dev_pm_qos_mtx); |
| } |
| |
| /** |
| * dev_pm_qos_expose_latency_limit - Expose PM QoS latency limit to user space. |
| * @dev: Device whose PM QoS latency limit is to be exposed to user space. |
| * @value: Initial value of the latency limit. |
| */ |
| int dev_pm_qos_expose_latency_limit(struct device *dev, s32 value) |
| { |
| struct dev_pm_qos_request *req; |
| int ret; |
| |
| if (!device_is_registered(dev) || value < 0) |
| return -EINVAL; |
| |
| req = kzalloc(sizeof(*req), GFP_KERNEL); |
| if (!req) |
| return -ENOMEM; |
| |
| ret = dev_pm_qos_add_request(dev, req, DEV_PM_QOS_RESUME_LATENCY, value); |
| if (ret < 0) { |
| kfree(req); |
| return ret; |
| } |
| |
| mutex_lock(&dev_pm_qos_sysfs_mtx); |
| |
| mutex_lock(&dev_pm_qos_mtx); |
| |
| if (IS_ERR_OR_NULL(dev->power.qos)) |
| ret = -ENODEV; |
| else if (dev->power.qos->resume_latency_req) |
| ret = -EEXIST; |
| |
| if (ret < 0) { |
| __dev_pm_qos_remove_request(req); |
| kfree(req); |
| mutex_unlock(&dev_pm_qos_mtx); |
| goto out; |
| } |
| dev->power.qos->resume_latency_req = req; |
| |
| mutex_unlock(&dev_pm_qos_mtx); |
| |
| ret = pm_qos_sysfs_add_resume_latency(dev); |
| if (ret) |
| dev_pm_qos_drop_user_request(dev, DEV_PM_QOS_RESUME_LATENCY); |
| |
| out: |
| mutex_unlock(&dev_pm_qos_sysfs_mtx); |
| return ret; |
| } |
| EXPORT_SYMBOL_GPL(dev_pm_qos_expose_latency_limit); |
| |
| static void __dev_pm_qos_hide_latency_limit(struct device *dev) |
| { |
| if (!IS_ERR_OR_NULL(dev->power.qos) && dev->power.qos->resume_latency_req) |
| __dev_pm_qos_drop_user_request(dev, DEV_PM_QOS_RESUME_LATENCY); |
| } |
| |
| /** |
| * dev_pm_qos_hide_latency_limit - Hide PM QoS latency limit from user space. |
| * @dev: Device whose PM QoS latency limit is to be hidden from user space. |
| */ |
| void dev_pm_qos_hide_latency_limit(struct device *dev) |
| { |
| mutex_lock(&dev_pm_qos_sysfs_mtx); |
| |
| pm_qos_sysfs_remove_resume_latency(dev); |
| |
| mutex_lock(&dev_pm_qos_mtx); |
| __dev_pm_qos_hide_latency_limit(dev); |
| mutex_unlock(&dev_pm_qos_mtx); |
| |
| mutex_unlock(&dev_pm_qos_sysfs_mtx); |
| } |
| EXPORT_SYMBOL_GPL(dev_pm_qos_hide_latency_limit); |
| |
| /** |
| * dev_pm_qos_expose_flags - Expose PM QoS flags of a device to user space. |
| * @dev: Device whose PM QoS flags are to be exposed to user space. |
| * @val: Initial values of the flags. |
| */ |
| int dev_pm_qos_expose_flags(struct device *dev, s32 val) |
| { |
| struct dev_pm_qos_request *req; |
| int ret; |
| |
| if (!device_is_registered(dev)) |
| return -EINVAL; |
| |
| req = kzalloc(sizeof(*req), GFP_KERNEL); |
| if (!req) |
| return -ENOMEM; |
| |
| ret = dev_pm_qos_add_request(dev, req, DEV_PM_QOS_FLAGS, val); |
| if (ret < 0) { |
| kfree(req); |
| return ret; |
| } |
| |
| pm_runtime_get_sync(dev); |
| mutex_lock(&dev_pm_qos_sysfs_mtx); |
| |
| mutex_lock(&dev_pm_qos_mtx); |
| |
| if (IS_ERR_OR_NULL(dev->power.qos)) |
| ret = -ENODEV; |
| else if (dev->power.qos->flags_req) |
| ret = -EEXIST; |
| |
| if (ret < 0) { |
| __dev_pm_qos_remove_request(req); |
| kfree(req); |
| mutex_unlock(&dev_pm_qos_mtx); |
| goto out; |
| } |
| dev->power.qos->flags_req = req; |
| |
| mutex_unlock(&dev_pm_qos_mtx); |
| |
| ret = pm_qos_sysfs_add_flags(dev); |
| if (ret) |
| dev_pm_qos_drop_user_request(dev, DEV_PM_QOS_FLAGS); |
| |
| out: |
| mutex_unlock(&dev_pm_qos_sysfs_mtx); |
| pm_runtime_put(dev); |
| return ret; |
| } |
| EXPORT_SYMBOL_GPL(dev_pm_qos_expose_flags); |
| |
| static void __dev_pm_qos_hide_flags(struct device *dev) |
| { |
| if (!IS_ERR_OR_NULL(dev->power.qos) && dev->power.qos->flags_req) |
| __dev_pm_qos_drop_user_request(dev, DEV_PM_QOS_FLAGS); |
| } |
| |
| /** |
| * dev_pm_qos_hide_flags - Hide PM QoS flags of a device from user space. |
| * @dev: Device whose PM QoS flags are to be hidden from user space. |
| */ |
| void dev_pm_qos_hide_flags(struct device *dev) |
| { |
| pm_runtime_get_sync(dev); |
| mutex_lock(&dev_pm_qos_sysfs_mtx); |
| |
| pm_qos_sysfs_remove_flags(dev); |
| |
| mutex_lock(&dev_pm_qos_mtx); |
| __dev_pm_qos_hide_flags(dev); |
| mutex_unlock(&dev_pm_qos_mtx); |
| |
| mutex_unlock(&dev_pm_qos_sysfs_mtx); |
| pm_runtime_put(dev); |
| } |
| EXPORT_SYMBOL_GPL(dev_pm_qos_hide_flags); |
| |
| /** |
| * dev_pm_qos_update_flags - Update PM QoS flags request owned by user space. |
| * @dev: Device to update the PM QoS flags request for. |
| * @mask: Flags to set/clear. |
| * @set: Whether to set or clear the flags (true means set). |
| */ |
| int dev_pm_qos_update_flags(struct device *dev, s32 mask, bool set) |
| { |
| s32 value; |
| int ret; |
| |
| pm_runtime_get_sync(dev); |
| mutex_lock(&dev_pm_qos_mtx); |
| |
| if (IS_ERR_OR_NULL(dev->power.qos) || !dev->power.qos->flags_req) { |
| ret = -EINVAL; |
| goto out; |
| } |
| |
| value = dev_pm_qos_requested_flags(dev); |
| if (set) |
| value |= mask; |
| else |
| value &= ~mask; |
| |
| ret = __dev_pm_qos_update_request(dev->power.qos->flags_req, value); |
| |
| out: |
| mutex_unlock(&dev_pm_qos_mtx); |
| pm_runtime_put(dev); |
| return ret; |
| } |
| |
| /** |
| * dev_pm_qos_get_user_latency_tolerance - Get user space latency tolerance. |
| * @dev: Device to obtain the user space latency tolerance for. |
| */ |
| s32 dev_pm_qos_get_user_latency_tolerance(struct device *dev) |
| { |
| s32 ret; |
| |
| mutex_lock(&dev_pm_qos_mtx); |
| ret = IS_ERR_OR_NULL(dev->power.qos) |
| || !dev->power.qos->latency_tolerance_req ? |
| PM_QOS_LATENCY_TOLERANCE_NO_CONSTRAINT : |
| dev->power.qos->latency_tolerance_req->data.lat.node.prio; |
| mutex_unlock(&dev_pm_qos_mtx); |
| return ret; |
| } |
| |
| /** |
| * dev_pm_qos_update_user_latency_tolerance - Update user space latency tolerance. |
| * @dev: Device to update the user space latency tolerance for. |
| * @val: New user space latency tolerance for @dev (negative values disable). |
| */ |
| int dev_pm_qos_update_user_latency_tolerance(struct device *dev, s32 val) |
| { |
| int ret; |
| |
| mutex_lock(&dev_pm_qos_mtx); |
| |
| if (IS_ERR_OR_NULL(dev->power.qos) |
| || !dev->power.qos->latency_tolerance_req) { |
| struct dev_pm_qos_request *req; |
| |
| if (val < 0) { |
| ret = -EINVAL; |
| goto out; |
| } |
| req = kzalloc(sizeof(*req), GFP_KERNEL); |
| if (!req) { |
| ret = -ENOMEM; |
| goto out; |
| } |
| ret = __dev_pm_qos_add_request(dev, req, DEV_PM_QOS_LATENCY_TOLERANCE, val); |
| if (ret < 0) { |
| kfree(req); |
| goto out; |
| } |
| dev->power.qos->latency_tolerance_req = req; |
| } else { |
| if (val < 0) { |
| __dev_pm_qos_drop_user_request(dev, DEV_PM_QOS_LATENCY_TOLERANCE); |
| ret = 0; |
| } else { |
| ret = __dev_pm_qos_update_request(dev->power.qos->latency_tolerance_req, val); |
| } |
| } |
| |
| out: |
| mutex_unlock(&dev_pm_qos_mtx); |
| return ret; |
| } |
| |
| /** |
| * dev_pm_qos_expose_latency_tolerance - Expose latency tolerance to userspace |
| * @dev: Device whose latency tolerance to expose |
| */ |
| int dev_pm_qos_expose_latency_tolerance(struct device *dev) |
| { |
| int ret; |
| |
| if (!dev->power.set_latency_tolerance) |
| return -EINVAL; |
| |
| mutex_lock(&dev_pm_qos_sysfs_mtx); |
| ret = pm_qos_sysfs_add_latency_tolerance(dev); |
| mutex_unlock(&dev_pm_qos_sysfs_mtx); |
| |
| return ret; |
| } |
| EXPORT_SYMBOL_GPL(dev_pm_qos_expose_latency_tolerance); |
| |
| /** |
| * dev_pm_qos_hide_latency_tolerance - Hide latency tolerance from userspace |
| * @dev: Device whose latency tolerance to hide |
| */ |
| void dev_pm_qos_hide_latency_tolerance(struct device *dev) |
| { |
| mutex_lock(&dev_pm_qos_sysfs_mtx); |
| pm_qos_sysfs_remove_latency_tolerance(dev); |
| mutex_unlock(&dev_pm_qos_sysfs_mtx); |
| |
| /* Remove the request from user space now */ |
| pm_runtime_get_sync(dev); |
| dev_pm_qos_update_user_latency_tolerance(dev, |
| PM_QOS_LATENCY_TOLERANCE_NO_CONSTRAINT); |
| pm_runtime_put(dev); |
| } |
| EXPORT_SYMBOL_GPL(dev_pm_qos_hide_latency_tolerance); |