Commit | Line | Data |
---|---|---|
c0672860 | 1 | |
1da177e4 LT |
2 | /* |
3 | * linux/drivers/cpufreq/cpufreq_userspace.c | |
4 | * | |
5 | * Copyright (C) 2001 Russell King | |
6 | * (C) 2002 - 2004 Dominik Brodowski <linux@brodo.de> | |
7 | * | |
8 | * This program is free software; you can redistribute it and/or modify | |
9 | * it under the terms of the GNU General Public License version 2 as | |
10 | * published by the Free Software Foundation. | |
11 | * | |
12 | */ | |
13 | ||
db701151 VK |
14 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
15 | ||
1da177e4 | 16 | #include <linux/cpufreq.h> |
d1922f02 VK |
17 | #include <linux/init.h> |
18 | #include <linux/module.h> | |
3fc54d37 | 19 | #include <linux/mutex.h> |
1da177e4 | 20 | |
b38868aa | 21 | static DEFINE_PER_CPU(unsigned int, cpu_is_managed); |
1bceb8d1 | 22 | static DEFINE_MUTEX(userspace_mutex); |
1da177e4 | 23 | |
32ee8c3e | 24 | /** |
1da177e4 | 25 | * cpufreq_set - set the CPU frequency |
9e76988e | 26 | * @policy: pointer to policy struct where freq is being set |
1da177e4 | 27 | * @freq: target frequency in kHz |
1da177e4 LT |
28 | * |
29 | * Sets the CPU frequency to freq. | |
30 | */ | |
9e76988e | 31 | static int cpufreq_set(struct cpufreq_policy *policy, unsigned int freq) |
1da177e4 LT |
32 | { |
33 | int ret = -EINVAL; | |
34 | ||
2d06d8c4 | 35 | pr_debug("cpufreq_set for cpu %u, freq %u kHz\n", policy->cpu, freq); |
1da177e4 | 36 | |
3fc54d37 | 37 | mutex_lock(&userspace_mutex); |
b38868aa | 38 | if (!per_cpu(cpu_is_managed, policy->cpu)) |
1da177e4 LT |
39 | goto err; |
40 | ||
c0672860 | 41 | ret = __cpufreq_driver_target(policy, freq, CPUFREQ_RELATION_L); |
1da177e4 | 42 | err: |
3fc54d37 | 43 | mutex_unlock(&userspace_mutex); |
1da177e4 LT |
44 | return ret; |
45 | } | |
46 | ||
9e76988e | 47 | static ssize_t show_speed(struct cpufreq_policy *policy, char *buf) |
1da177e4 | 48 | { |
d1922f02 | 49 | return sprintf(buf, "%u\n", policy->cur); |
1da177e4 LT |
50 | } |
51 | ||
1da177e4 LT |
52 | static int cpufreq_governor_userspace(struct cpufreq_policy *policy, |
53 | unsigned int event) | |
54 | { | |
55 | unsigned int cpu = policy->cpu; | |
914f7c31 JG |
56 | int rc = 0; |
57 | ||
1da177e4 LT |
58 | switch (event) { |
59 | case CPUFREQ_GOV_START: | |
1da177e4 | 60 | BUG_ON(!policy->cur); |
d1922f02 | 61 | pr_debug("started managing cpu %u\n", cpu); |
c7f652e0 | 62 | |
d1922f02 | 63 | mutex_lock(&userspace_mutex); |
b38868aa | 64 | per_cpu(cpu_is_managed, cpu) = 1; |
3fc54d37 | 65 | mutex_unlock(&userspace_mutex); |
1da177e4 LT |
66 | break; |
67 | case CPUFREQ_GOV_STOP: | |
d1922f02 | 68 | pr_debug("managing cpu %u stopped\n", cpu); |
c7f652e0 | 69 | |
d1922f02 | 70 | mutex_lock(&userspace_mutex); |
b38868aa | 71 | per_cpu(cpu_is_managed, cpu) = 0; |
3fc54d37 | 72 | mutex_unlock(&userspace_mutex); |
1da177e4 LT |
73 | break; |
74 | case CPUFREQ_GOV_LIMITS: | |
3fc54d37 | 75 | mutex_lock(&userspace_mutex); |
d1922f02 | 76 | pr_debug("limit event for cpu %u: %u - %u kHz, currently %u kHz\n", |
c0672860 | 77 | cpu, policy->min, policy->max, |
d1922f02 VK |
78 | policy->cur); |
79 | ||
80 | if (policy->max < policy->cur) | |
c0672860 TR |
81 | __cpufreq_driver_target(policy, policy->max, |
82 | CPUFREQ_RELATION_H); | |
d1922f02 | 83 | else if (policy->min > policy->cur) |
c0672860 TR |
84 | __cpufreq_driver_target(policy, policy->min, |
85 | CPUFREQ_RELATION_L); | |
3fc54d37 | 86 | mutex_unlock(&userspace_mutex); |
1da177e4 LT |
87 | break; |
88 | } | |
914f7c31 | 89 | return rc; |
1da177e4 LT |
90 | } |
91 | ||
c4d14bc0 SW |
92 | #ifndef CONFIG_CPU_FREQ_DEFAULT_GOV_USERSPACE |
93 | static | |
94 | #endif | |
1da177e4 LT |
95 | struct cpufreq_governor cpufreq_gov_userspace = { |
96 | .name = "userspace", | |
97 | .governor = cpufreq_governor_userspace, | |
9e76988e VP |
98 | .store_setspeed = cpufreq_set, |
99 | .show_setspeed = show_speed, | |
1da177e4 LT |
100 | .owner = THIS_MODULE, |
101 | }; | |
1da177e4 LT |
102 | |
103 | static int __init cpufreq_gov_userspace_init(void) | |
104 | { | |
1da177e4 LT |
105 | return cpufreq_register_governor(&cpufreq_gov_userspace); |
106 | } | |
107 | ||
1da177e4 LT |
108 | static void __exit cpufreq_gov_userspace_exit(void) |
109 | { | |
110 | cpufreq_unregister_governor(&cpufreq_gov_userspace); | |
1da177e4 LT |
111 | } |
112 | ||
1bceb8d1 DJ |
113 | MODULE_AUTHOR("Dominik Brodowski <linux@brodo.de>, " |
114 | "Russell King <rmk@arm.linux.org.uk>"); | |
115 | MODULE_DESCRIPTION("CPUfreq policy governor 'userspace'"); | |
116 | MODULE_LICENSE("GPL"); | |
1da177e4 | 117 | |
6915719b | 118 | #ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_USERSPACE |
1da177e4 | 119 | fs_initcall(cpufreq_gov_userspace_init); |
6915719b JW |
120 | #else |
121 | module_init(cpufreq_gov_userspace_init); | |
122 | #endif | |
1da177e4 | 123 | module_exit(cpufreq_gov_userspace_exit); |