1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-only
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * Abstract code for CPUFreq governor tunable sysfs attributes.
4*4882a593Smuzhiyun *
5*4882a593Smuzhiyun * Copyright (C) 2016, Intel Corporation
6*4882a593Smuzhiyun * Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
7*4882a593Smuzhiyun */
8*4882a593Smuzhiyun
9*4882a593Smuzhiyun #include "cpufreq_governor.h"
10*4882a593Smuzhiyun
to_gov_attr_set(struct kobject * kobj)11*4882a593Smuzhiyun static inline struct gov_attr_set *to_gov_attr_set(struct kobject *kobj)
12*4882a593Smuzhiyun {
13*4882a593Smuzhiyun return container_of(kobj, struct gov_attr_set, kobj);
14*4882a593Smuzhiyun }
15*4882a593Smuzhiyun
to_gov_attr(struct attribute * attr)16*4882a593Smuzhiyun static inline struct governor_attr *to_gov_attr(struct attribute *attr)
17*4882a593Smuzhiyun {
18*4882a593Smuzhiyun return container_of(attr, struct governor_attr, attr);
19*4882a593Smuzhiyun }
20*4882a593Smuzhiyun
governor_show(struct kobject * kobj,struct attribute * attr,char * buf)21*4882a593Smuzhiyun static ssize_t governor_show(struct kobject *kobj, struct attribute *attr,
22*4882a593Smuzhiyun char *buf)
23*4882a593Smuzhiyun {
24*4882a593Smuzhiyun struct governor_attr *gattr = to_gov_attr(attr);
25*4882a593Smuzhiyun
26*4882a593Smuzhiyun return gattr->show(to_gov_attr_set(kobj), buf);
27*4882a593Smuzhiyun }
28*4882a593Smuzhiyun
governor_store(struct kobject * kobj,struct attribute * attr,const char * buf,size_t count)29*4882a593Smuzhiyun static ssize_t governor_store(struct kobject *kobj, struct attribute *attr,
30*4882a593Smuzhiyun const char *buf, size_t count)
31*4882a593Smuzhiyun {
32*4882a593Smuzhiyun struct gov_attr_set *attr_set = to_gov_attr_set(kobj);
33*4882a593Smuzhiyun struct governor_attr *gattr = to_gov_attr(attr);
34*4882a593Smuzhiyun int ret;
35*4882a593Smuzhiyun
36*4882a593Smuzhiyun mutex_lock(&attr_set->update_lock);
37*4882a593Smuzhiyun ret = attr_set->usage_count ? gattr->store(attr_set, buf, count) : -EBUSY;
38*4882a593Smuzhiyun mutex_unlock(&attr_set->update_lock);
39*4882a593Smuzhiyun return ret;
40*4882a593Smuzhiyun }
41*4882a593Smuzhiyun
42*4882a593Smuzhiyun const struct sysfs_ops governor_sysfs_ops = {
43*4882a593Smuzhiyun .show = governor_show,
44*4882a593Smuzhiyun .store = governor_store,
45*4882a593Smuzhiyun };
46*4882a593Smuzhiyun EXPORT_SYMBOL_GPL(governor_sysfs_ops);
47*4882a593Smuzhiyun
gov_attr_set_init(struct gov_attr_set * attr_set,struct list_head * list_node)48*4882a593Smuzhiyun void gov_attr_set_init(struct gov_attr_set *attr_set, struct list_head *list_node)
49*4882a593Smuzhiyun {
50*4882a593Smuzhiyun INIT_LIST_HEAD(&attr_set->policy_list);
51*4882a593Smuzhiyun mutex_init(&attr_set->update_lock);
52*4882a593Smuzhiyun attr_set->usage_count = 1;
53*4882a593Smuzhiyun list_add(list_node, &attr_set->policy_list);
54*4882a593Smuzhiyun }
55*4882a593Smuzhiyun EXPORT_SYMBOL_GPL(gov_attr_set_init);
56*4882a593Smuzhiyun
gov_attr_set_get(struct gov_attr_set * attr_set,struct list_head * list_node)57*4882a593Smuzhiyun void gov_attr_set_get(struct gov_attr_set *attr_set, struct list_head *list_node)
58*4882a593Smuzhiyun {
59*4882a593Smuzhiyun mutex_lock(&attr_set->update_lock);
60*4882a593Smuzhiyun attr_set->usage_count++;
61*4882a593Smuzhiyun list_add(list_node, &attr_set->policy_list);
62*4882a593Smuzhiyun mutex_unlock(&attr_set->update_lock);
63*4882a593Smuzhiyun }
64*4882a593Smuzhiyun EXPORT_SYMBOL_GPL(gov_attr_set_get);
65*4882a593Smuzhiyun
gov_attr_set_put(struct gov_attr_set * attr_set,struct list_head * list_node)66*4882a593Smuzhiyun unsigned int gov_attr_set_put(struct gov_attr_set *attr_set, struct list_head *list_node)
67*4882a593Smuzhiyun {
68*4882a593Smuzhiyun unsigned int count;
69*4882a593Smuzhiyun
70*4882a593Smuzhiyun mutex_lock(&attr_set->update_lock);
71*4882a593Smuzhiyun list_del(list_node);
72*4882a593Smuzhiyun count = --attr_set->usage_count;
73*4882a593Smuzhiyun mutex_unlock(&attr_set->update_lock);
74*4882a593Smuzhiyun if (count)
75*4882a593Smuzhiyun return count;
76*4882a593Smuzhiyun
77*4882a593Smuzhiyun mutex_destroy(&attr_set->update_lock);
78*4882a593Smuzhiyun kobject_put(&attr_set->kobj);
79*4882a593Smuzhiyun return 0;
80*4882a593Smuzhiyun }
81*4882a593Smuzhiyun EXPORT_SYMBOL_GPL(gov_attr_set_put);
82