[CPUFREQ] allow use of the powersave governor as the default one
[linux-2.6.git] / drivers / cpufreq / cpufreq_powersave.c
1 /*
2  *  linux/drivers/cpufreq/cpufreq_powersave.c
3  *
4  *  Copyright (C) 2002 - 2003 Dominik Brodowski <linux@brodo.de>
5  *
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  *
11  */
12
13 #include <linux/kernel.h>
14 #include <linux/module.h>
15 #include <linux/cpufreq.h>
16 #include <linux/init.h>
17
18 #define dprintk(msg...) \
19         cpufreq_debug_printk(CPUFREQ_DEBUG_GOVERNOR, "powersave", msg)
20
21 static int cpufreq_governor_powersave(struct cpufreq_policy *policy,
22                                         unsigned int event)
23 {
24         switch (event) {
25         case CPUFREQ_GOV_START:
26         case CPUFREQ_GOV_LIMITS:
27                 dprintk("setting to %u kHz because of event %u\n",
28                                                         policy->min, event);
29                 __cpufreq_driver_target(policy, policy->min,
30                                                 CPUFREQ_RELATION_L);
31                 break;
32         default:
33                 break;
34         }
35         return 0;
36 }
37
38 struct cpufreq_governor cpufreq_gov_powersave = {
39         .name           = "powersave",
40         .governor       = cpufreq_governor_powersave,
41         .owner          = THIS_MODULE,
42 };
43 EXPORT_SYMBOL(cpufreq_gov_powersave);
44
45 static int __init cpufreq_gov_powersave_init(void)
46 {
47         return cpufreq_register_governor(&cpufreq_gov_powersave);
48 }
49
50
51 static void __exit cpufreq_gov_powersave_exit(void)
52 {
53         cpufreq_unregister_governor(&cpufreq_gov_powersave);
54 }
55
56
57 MODULE_AUTHOR("Dominik Brodowski <linux@brodo.de>");
58 MODULE_DESCRIPTION("CPUfreq policy governor 'powersave'");
59 MODULE_LICENSE("GPL");
60
61 #ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_POWERSAVE
62 fs_initcall(cpufreq_gov_powersave_init);
63 #else
64 module_init(cpufreq_gov_powersave_init);
65 #endif
66 module_exit(cpufreq_gov_powersave_exit);