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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  14
  15 #include <linux/cpufreq.h>
  16 #include <linux/init.h>
  17 #include <linux/module.h>
  18
  19 static int cpufreq_governor_powersave(struct cpufreq_policy *policy,
  20                                         unsigned int event)
  21 {
  22         switch (event) {
  23         case CPUFREQ_GOV_START:
  24         case CPUFREQ_GOV_LIMITS:
  25                 pr_debug("setting to %u kHz because of event %u\n",
  26                                                         policy->min, event);
  27                 __cpufreq_driver_target(policy, policy->min,
  28                                                 CPUFREQ_RELATION_L);
  29                 break;
  30         default:
  31                 break;
  32         }
  33         return 0;
  34 }
  35
  36 #ifndef CONFIG_CPU_FREQ_DEFAULT_GOV_POWERSAVE
  37 static
  38 #endif
  39 struct cpufreq_governor cpufreq_gov_powersave = {
  40         .name           = "powersave",
  41         .governor       = cpufreq_governor_powersave,
  42         .owner          = THIS_MODULE,
  43 };
  44
  45 static int __init cpufreq_gov_powersave_init(void)
  46 {
  47         return cpufreq_register_governor(&cpufreq_gov_powersave);
  48 }
  49
  50 static void __exit cpufreq_gov_powersave_exit(void)
  51 {
  52         cpufreq_unregister_governor(&cpufreq_gov_powersave);
  53 }
  54
  55 MODULE_AUTHOR("Dominik Brodowski <linux@brodo.de>");
  56 MODULE_DESCRIPTION("CPUfreq policy governor 'powersave'");
  57 MODULE_LICENSE("GPL");
  58
  59 #ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_POWERSAVE
  60 fs_initcall(cpufreq_gov_powersave_init);
  61 #else
  62 module_init(cpufreq_gov_powersave_init);
  63 #endif
  64 module_exit(cpufreq_gov_powersave_exit);