diff options
Diffstat (limited to 'drivers/base/power/qos.c')
| -rw-r--r-- | drivers/base/power/qos.c | 453 |
1 files changed, 331 insertions, 122 deletions
diff --git a/drivers/base/power/qos.c b/drivers/base/power/qos.c index 5c1361a9e5dd..ff393cba7649 100644 --- a/drivers/base/power/qos.c +++ b/drivers/base/power/qos.c @@ -1,13 +1,9 @@ +// SPDX-License-Identifier: GPL-2.0 /* * 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: @@ -17,15 +13,12 @@ * * 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 + * . The per-device constraints data struct ptr is stored 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. @@ -49,8 +42,6 @@ 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. @@ -64,6 +55,8 @@ enum pm_qos_flags_status __dev_pm_qos_flags(struct device *dev, s32 mask) struct pm_qos_flags *pqf; s32 val; + lockdep_assert_held(&dev->power.lock); + if (IS_ERR_OR_NULL(qos)) return PM_QOS_FLAGS_UNDEFINED; @@ -97,32 +90,54 @@ enum pm_qos_flags_status dev_pm_qos_flags(struct device *dev, s32 mask) EXPORT_SYMBOL_GPL(dev_pm_qos_flags); /** - * __dev_pm_qos_read_value - Get PM QoS constraint for a given device. + * __dev_pm_qos_resume_latency - Get resume latency 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) +s32 __dev_pm_qos_resume_latency(struct device *dev) { - return IS_ERR_OR_NULL(dev->power.qos) ? - 0 : pm_qos_read_value(&dev->power.qos->latency); + lockdep_assert_held(&dev->power.lock); + + return dev_pm_qos_raw_resume_latency(dev); } /** * dev_pm_qos_read_value - Get PM QoS constraint for a given device (locked). * @dev: Device to get the PM QoS constraint value for. + * @type: QoS request type. */ -s32 dev_pm_qos_read_value(struct device *dev) +s32 dev_pm_qos_read_value(struct device *dev, enum dev_pm_qos_req_type type) { + struct dev_pm_qos *qos = dev->power.qos; unsigned long flags; s32 ret; spin_lock_irqsave(&dev->power.lock, flags); - ret = __dev_pm_qos_read_value(dev); + + switch (type) { + case DEV_PM_QOS_RESUME_LATENCY: + ret = IS_ERR_OR_NULL(qos) ? PM_QOS_RESUME_LATENCY_NO_CONSTRAINT + : pm_qos_read_value(&qos->resume_latency); + break; + case DEV_PM_QOS_MIN_FREQUENCY: + ret = IS_ERR_OR_NULL(qos) ? PM_QOS_MIN_FREQUENCY_DEFAULT_VALUE + : freq_qos_read_value(&qos->freq, FREQ_QOS_MIN); + break; + case DEV_PM_QOS_MAX_FREQUENCY: + ret = IS_ERR_OR_NULL(qos) ? PM_QOS_MAX_FREQUENCY_DEFAULT_VALUE + : freq_qos_read_value(&qos->freq, FREQ_QOS_MAX); + break; + default: + WARN_ON(1); + ret = 0; + } + spin_unlock_irqrestore(&dev->power.lock, flags); return ret; } +EXPORT_SYMBOL_GPL(dev_pm_qos_read_value); /** * apply_constraint - Add/modify/remove device PM QoS request. @@ -131,8 +146,7 @@ s32 dev_pm_qos_read_value(struct device *dev) * @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) @@ -141,16 +155,25 @@ static int apply_constraint(struct dev_pm_qos_request *req, int ret; switch(req->type) { - case DEV_PM_QOS_LATENCY: - ret = pm_qos_update_target(&qos->latency, &req->data.pnode, - action, value); + case DEV_PM_QOS_RESUME_LATENCY: + if (WARN_ON(action != PM_QOS_REMOVE_REQ && value < 0)) + value = 0; + + ret = pm_qos_update_target(&qos->resume_latency, + &req->data.pnode, action, value); + break; + case DEV_PM_QOS_LATENCY_TOLERANCE: + ret = pm_qos_update_target(&qos->latency_tolerance, + &req->data.pnode, action, value); if (ret) { - value = pm_qos_read_value(&qos->latency); - blocking_notifier_call_chain(&dev_pm_notifiers, - (unsigned long)value, - req); + value = pm_qos_read_value(&qos->latency_tolerance); + req->dev->power.set_latency_tolerance(req->dev, value); } break; + case DEV_PM_QOS_MIN_FREQUENCY: + case DEV_PM_QOS_MAX_FREQUENCY: + ret = freq_qos_apply(&req->data.freq, action, value); + break; case DEV_PM_QOS_FLAGS: ret = pm_qos_update_flags(&qos->flags, &req->data.flr, action, value); @@ -179,19 +202,29 @@ static int dev_pm_qos_constraints_allocate(struct device *dev) if (!qos) return -ENOMEM; - n = kzalloc(sizeof(*n), GFP_KERNEL); + n = kcalloc(3, sizeof(*n), GFP_KERNEL); if (!n) { kfree(qos); return -ENOMEM; } - BLOCKING_INIT_NOTIFIER_HEAD(n); - c = &qos->latency; + c = &qos->resume_latency; plist_head_init(&c->list); - c->target_value = PM_QOS_DEV_LAT_DEFAULT_VALUE; - c->default_value = PM_QOS_DEV_LAT_DEFAULT_VALUE; + 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_NO_CONSTRAINT; c->type = PM_QOS_MIN; c->notifiers = n; + BLOCKING_INIT_NOTIFIER_HEAD(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; + + freq_constraints_init(&qos->freq); INIT_LIST_HEAD(&qos->flags.list); @@ -224,7 +257,7 @@ void dev_pm_qos_constraints_destroy(struct device *dev) * 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_latency(dev); + pm_qos_sysfs_remove_resume_latency(dev); pm_qos_sysfs_remove_flags(dev); mutex_lock(&dev_pm_qos_mtx); @@ -237,7 +270,7 @@ void dev_pm_qos_constraints_destroy(struct device *dev) goto out; /* Flush the constraints lists for the device. */ - c = &qos->latency; + c = &qos->resume_latency; plist_for_each_entry_safe(req, tmp, &c->list, data.pnode) { /* * Update constraints list and call the notification @@ -246,6 +279,27 @@ void dev_pm_qos_constraints_destroy(struct device *dev) 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.pnode) { + apply_constraint(req, PM_QOS_REMOVE_REQ, PM_QOS_DEFAULT_VALUE); + memset(req, 0, sizeof(*req)); + } + + c = &qos->freq.min_freq; + plist_for_each_entry_safe(req, tmp, &c->list, data.freq.pnode) { + apply_constraint(req, PM_QOS_REMOVE_REQ, + PM_QOS_MIN_FREQUENCY_DEFAULT_VALUE); + memset(req, 0, sizeof(*req)); + } + + c = &qos->freq.max_freq; + plist_for_each_entry_safe(req, tmp, &c->list, data.freq.pnode) { + apply_constraint(req, PM_QOS_REMOVE_REQ, + PM_QOS_MAX_FREQUENCY_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); @@ -256,7 +310,7 @@ void dev_pm_qos_constraints_destroy(struct device *dev) dev->power.qos = ERR_PTR(-ENODEV); spin_unlock_irq(&dev->power.lock); - kfree(c->notifiers); + kfree(qos->resume_latency.notifiers); kfree(qos); out: @@ -265,6 +319,51 @@ void dev_pm_qos_constraints_destroy(struct device *dev) mutex_unlock(&dev_pm_qos_sysfs_mtx); } +static bool dev_pm_qos_invalid_req_type(struct device *dev, + enum dev_pm_qos_req_type type) +{ + return 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 || !req || dev_pm_qos_invalid_req_type(dev, type)) + 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) + return ret; + + req->dev = dev; + req->type = type; + if (req->type == DEV_PM_QOS_MIN_FREQUENCY) + ret = freq_qos_add_request(&dev->power.qos->freq, + &req->data.freq, + FREQ_QOS_MIN, value); + else if (req->type == DEV_PM_QOS_MAX_FREQUENCY) + ret = freq_qos_add_request(&dev->power.qos->freq, + &req->data.freq, + FREQ_QOS_MAX, value); + else + 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 @@ -290,31 +389,11 @@ void dev_pm_qos_constraints_destroy(struct device *dev) 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 || !req) /*guard against callers passing in null */ - return -EINVAL; - - if (WARN(dev_pm_qos_request_active(req), - "%s() called for already added request\n", __func__)) - return -EINVAL; + int ret; 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); - - 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); - } - + 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); @@ -341,9 +420,14 @@ static int __dev_pm_qos_update_request(struct dev_pm_qos_request *req, return -ENODEV; switch(req->type) { - case DEV_PM_QOS_LATENCY: + case DEV_PM_QOS_RESUME_LATENCY: + case DEV_PM_QOS_LATENCY_TOLERANCE: curr_value = req->data.pnode.prio; break; + case DEV_PM_QOS_MIN_FREQUENCY: + case DEV_PM_QOS_MAX_FREQUENCY: + curr_value = req->data.freq.pnode.prio; + break; case DEV_PM_QOS_FLAGS: curr_value = req->data.flr.flags; break; @@ -441,6 +525,7 @@ EXPORT_SYMBOL_GPL(dev_pm_qos_remove_request); * * @dev: target device for the constraint * @notifier: notifier block managed by caller. + * @type: request type. * * Will register the notifier into a notification chain that gets called * upon changes to the target value for the device. @@ -448,7 +533,8 @@ EXPORT_SYMBOL_GPL(dev_pm_qos_remove_request); * 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 dev_pm_qos_add_notifier(struct device *dev, struct notifier_block *notifier, + enum dev_pm_qos_req_type type) { int ret = 0; @@ -459,10 +545,28 @@ int dev_pm_qos_add_notifier(struct device *dev, struct notifier_block *notifier) else if (!dev->power.qos) ret = dev_pm_qos_constraints_allocate(dev); - if (!ret) - ret = blocking_notifier_chain_register( - dev->power.qos->latency.notifiers, notifier); + if (ret) + goto unlock; + + switch (type) { + case DEV_PM_QOS_RESUME_LATENCY: + ret = blocking_notifier_chain_register(dev->power.qos->resume_latency.notifiers, + notifier); + break; + case DEV_PM_QOS_MIN_FREQUENCY: + ret = freq_qos_add_notifier(&dev->power.qos->freq, + FREQ_QOS_MIN, notifier); + break; + case DEV_PM_QOS_MAX_FREQUENCY: + ret = freq_qos_add_notifier(&dev->power.qos->freq, + FREQ_QOS_MAX, notifier); + break; + default: + WARN_ON(1); + ret = -EINVAL; + } +unlock: mutex_unlock(&dev_pm_qos_mtx); return ret; } @@ -474,76 +578,77 @@ EXPORT_SYMBOL_GPL(dev_pm_qos_add_notifier); * * @dev: target device for the constraint * @notifier: notifier block to be removed. + * @type: request type. * * 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) + struct notifier_block *notifier, + enum dev_pm_qos_req_type type) { - int retval = 0; + int ret = 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->latency.notifiers, - notifier); + if (IS_ERR_OR_NULL(dev->power.qos)) + goto unlock; + switch (type) { + case DEV_PM_QOS_RESUME_LATENCY: + ret = blocking_notifier_chain_unregister(dev->power.qos->resume_latency.notifiers, + notifier); + break; + case DEV_PM_QOS_MIN_FREQUENCY: + ret = freq_qos_remove_notifier(&dev->power.qos->freq, + FREQ_QOS_MIN, notifier); + break; + case DEV_PM_QOS_MAX_FREQUENCY: + ret = freq_qos_remove_notifier(&dev->power.qos->freq, + FREQ_QOS_MAX, notifier); + break; + default: + WARN_ON(1); + ret = -EINVAL; + } + +unlock: mutex_unlock(&dev_pm_qos_mtx); - return retval; + return ret; } 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, s32 value) + struct dev_pm_qos_request *req, + enum dev_pm_qos_req_type type, s32 value) { struct device *ancestor = dev->parent; int ret = -ENODEV; - while (ancestor && !ancestor->power.ignore_children) - ancestor = ancestor->parent; + 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, - DEV_PM_QOS_LATENCY, value); + ret = dev_pm_qos_add_request(ancestor, req, type, value); if (ret < 0) req->dev = NULL; @@ -552,21 +657,27 @@ int dev_pm_qos_add_ancestor_request(struct device *dev, } EXPORT_SYMBOL_GPL(dev_pm_qos_add_ancestor_request); -#ifdef CONFIG_PM_RUNTIME 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_LATENCY: - req = dev->power.qos->latency_req; - dev->power.qos->latency_req = NULL; + 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; + default: + WARN_ON(1); + return; } __dev_pm_qos_remove_request(req); kfree(req); @@ -597,7 +708,7 @@ int dev_pm_qos_expose_latency_limit(struct device *dev, s32 value) if (!req) return -ENOMEM; - ret = dev_pm_qos_add_request(dev, req, DEV_PM_QOS_LATENCY, value); + ret = dev_pm_qos_add_request(dev, req, DEV_PM_QOS_RESUME_LATENCY, value); if (ret < 0) { kfree(req); return ret; @@ -609,7 +720,7 @@ int dev_pm_qos_expose_latency_limit(struct device *dev, s32 value) if (IS_ERR_OR_NULL(dev->power.qos)) ret = -ENODEV; - else if (dev->power.qos->latency_req) + else if (dev->power.qos->resume_latency_req) ret = -EEXIST; if (ret < 0) { @@ -618,13 +729,13 @@ int dev_pm_qos_expose_latency_limit(struct device *dev, s32 value) mutex_unlock(&dev_pm_qos_mtx); goto out; } - dev->power.qos->latency_req = req; + dev->power.qos->resume_latency_req = req; mutex_unlock(&dev_pm_qos_mtx); - ret = pm_qos_sysfs_add_latency(dev); + ret = pm_qos_sysfs_add_resume_latency(dev); if (ret) - dev_pm_qos_drop_user_request(dev, DEV_PM_QOS_LATENCY); + dev_pm_qos_drop_user_request(dev, DEV_PM_QOS_RESUME_LATENCY); out: mutex_unlock(&dev_pm_qos_sysfs_mtx); @@ -634,8 +745,8 @@ 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->latency_req) - __dev_pm_qos_drop_user_request(dev, DEV_PM_QOS_LATENCY); + 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); } /** @@ -646,7 +757,7 @@ void dev_pm_qos_hide_latency_limit(struct device *dev) { mutex_lock(&dev_pm_qos_sysfs_mtx); - pm_qos_sysfs_remove_latency(dev); + pm_qos_sysfs_remove_resume_latency(dev); mutex_lock(&dev_pm_qos_mtx); __dev_pm_qos_hide_latency_limit(dev); @@ -768,7 +879,105 @@ int dev_pm_qos_update_flags(struct device *dev, s32 mask, bool set) pm_runtime_put(dev); return ret; } -#else /* !CONFIG_PM_RUNTIME */ -static void __dev_pm_qos_hide_latency_limit(struct device *dev) {} -static void __dev_pm_qos_hide_flags(struct device *dev) {} -#endif /* CONFIG_PM_RUNTIME */ + +/** + * 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.pnode.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) { + if (val == PM_QOS_LATENCY_TOLERANCE_NO_CONSTRAINT) + ret = 0; + else + 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; +} +EXPORT_SYMBOL_GPL(dev_pm_qos_update_user_latency_tolerance); + +/** + * 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); |
