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 
cpufreq_governor_powersave(struct cpufreq_policy * policy,unsigned int event)18 static int cpufreq_governor_powersave(struct cpufreq_policy *policy,
19 					unsigned int event)
20 {
21 	switch (event) {
22 	case CPUFREQ_GOV_START:
23 	case CPUFREQ_GOV_LIMITS:
24 		pr_debug("setting to %u kHz because of event %u\n",
25 							policy->min, event);
26 		__cpufreq_driver_target(policy, policy->min,
27 						CPUFREQ_RELATION_L);
28 		break;
29 	default:
30 		break;
31 	}
32 	return 0;
33 }
34 
35 #ifndef CONFIG_CPU_FREQ_DEFAULT_GOV_POWERSAVE
36 static
37 #endif
38 struct cpufreq_governor cpufreq_gov_powersave = {
39 	.name		= "powersave",
40 	.governor	= cpufreq_governor_powersave,
41 	.owner		= THIS_MODULE,
42 };
43 
cpufreq_gov_powersave_init(void)44 static int __init cpufreq_gov_powersave_init(void)
45 {
46 	return cpufreq_register_governor(&cpufreq_gov_powersave);
47 }
48 
49 
cpufreq_gov_powersave_exit(void)50 static void __exit cpufreq_gov_powersave_exit(void)
51 {
52 	cpufreq_unregister_governor(&cpufreq_gov_powersave);
53 }
54 
55 
56 MODULE_AUTHOR("Dominik Brodowski <linux@brodo.de>");
57 MODULE_DESCRIPTION("CPUfreq policy governor 'powersave'");
58 MODULE_LICENSE("GPL");
59 
60 #ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_POWERSAVE
61 fs_initcall(cpufreq_gov_powersave_init);
62 #else
63 module_init(cpufreq_gov_powersave_init);
64 #endif
65 module_exit(cpufreq_gov_powersave_exit);
66