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 #ifndef CONFIG_CPU_FREQ_DEFAULT_GOV_POWERSAVE
39 static
40 #endif
41 struct cpufreq_governor cpufreq_gov_powersave = {
42 	.name		= "powersave",
43 	.governor	= cpufreq_governor_powersave,
44 	.owner		= THIS_MODULE,
45 };
46 
47 static int __init cpufreq_gov_powersave_init(void)
48 {
49 	return cpufreq_register_governor(&cpufreq_gov_powersave);
50 }
51 
52 
53 static void __exit cpufreq_gov_powersave_exit(void)
54 {
55 	cpufreq_unregister_governor(&cpufreq_gov_powersave);
56 }
57 
58 
59 MODULE_AUTHOR("Dominik Brodowski <linux@brodo.de>");
60 MODULE_DESCRIPTION("CPUfreq policy governor 'powersave'");
61 MODULE_LICENSE("GPL");
62 
63 #ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_POWERSAVE
64 fs_initcall(cpufreq_gov_powersave_init);
65 #else
66 module_init(cpufreq_gov_powersave_init);
67 #endif
68 module_exit(cpufreq_gov_powersave_exit);
69