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);