1 // SPDX-License-Identifier: GPL-2.0-only
3 * Abstract code for CPUFreq governor tunable sysfs attributes.
5 * Copyright (C) 2016, Intel Corporation
6 * Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
9 #include "cpufreq_governor.h"
11 static inline struct gov_attr_set *to_gov_attr_set(struct kobject *kobj)
13 return container_of(kobj, struct gov_attr_set, kobj);
16 static inline struct governor_attr *to_gov_attr(struct attribute *attr)
18 return container_of(attr, struct governor_attr, attr);
21 static ssize_t governor_show(struct kobject *kobj, struct attribute *attr,
24 struct governor_attr *gattr = to_gov_attr(attr);
26 return gattr->show(to_gov_attr_set(kobj), buf);
29 static ssize_t governor_store(struct kobject *kobj, struct attribute *attr,
30 const char *buf, size_t count)
32 struct gov_attr_set *attr_set = to_gov_attr_set(kobj);
33 struct governor_attr *gattr = to_gov_attr(attr);
36 mutex_lock(&attr_set->update_lock);
37 ret = attr_set->usage_count ? gattr->store(attr_set, buf, count) : -EBUSY;
38 mutex_unlock(&attr_set->update_lock);
42 const struct sysfs_ops governor_sysfs_ops = {
43 .show = governor_show,
44 .store = governor_store,
46 EXPORT_SYMBOL_GPL(governor_sysfs_ops);
48 void gov_attr_set_init(struct gov_attr_set *attr_set, struct list_head *list_node)
50 INIT_LIST_HEAD(&attr_set->policy_list);
51 mutex_init(&attr_set->update_lock);
52 attr_set->usage_count = 1;
53 list_add(list_node, &attr_set->policy_list);
55 EXPORT_SYMBOL_GPL(gov_attr_set_init);
57 void gov_attr_set_get(struct gov_attr_set *attr_set, struct list_head *list_node)
59 mutex_lock(&attr_set->update_lock);
60 attr_set->usage_count++;
61 list_add(list_node, &attr_set->policy_list);
62 mutex_unlock(&attr_set->update_lock);
64 EXPORT_SYMBOL_GPL(gov_attr_set_get);
66 unsigned int gov_attr_set_put(struct gov_attr_set *attr_set, struct list_head *list_node)
70 mutex_lock(&attr_set->update_lock);
72 count = --attr_set->usage_count;
73 mutex_unlock(&attr_set->update_lock);
77 kobject_put(&attr_set->kobj);
78 mutex_destroy(&attr_set->update_lock);
81 EXPORT_SYMBOL_GPL(gov_attr_set_put);