LXR linux/drivers/devfreq/governor

   1/*
   2 *  linux/drivers/devfreq/governor_performance.c
   3 *
   4 *  Copyright (C) 2011 Samsung Electronics
   5 *      MyungJoo Ham <myungjoo.ham@samsung.com>
   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#include <linux/devfreq.h>
  13#include <linux/module.h>
  14#include "governor.h"
  15
  16static int devfreq_performance_func(struct devfreq *df,
  17                                    unsigned long *freq)
  18{
  19        /*
  20         * target callback should be able to get floor value as
  21         * said in devfreq.h
  22         */
  23        if (!df->max_freq)
  24                *freq = UINT_MAX;
  25        else
  26                *freq = df->max_freq;
  27        return 0;
  28}
  29
  30static int devfreq_performance_handler(struct devfreq *devfreq,
  31                                unsigned int event, void *data)
  32{
  33        int ret = 0;
  34
  35        if (event == DEVFREQ_GOV_START) {
  36                mutex_lock(&devfreq->lock);
  37                ret = update_devfreq(devfreq);
  38                mutex_unlock(&devfreq->lock);
  39        }
  40
  41        return ret;
  42}
  43
  44static struct devfreq_governor devfreq_performance = {
  45        .name = DEVFREQ_GOV_PERFORMANCE,
  46        .get_target_freq = devfreq_performance_func,
  47        .event_handler = devfreq_performance_handler,
  48};
  49
  50static int __init devfreq_performance_init(void)
  51{
  52        return devfreq_add_governor(&devfreq_performance);
  53}
  54subsys_initcall(devfreq_performance_init);
  55
  56static void __exit devfreq_performance_exit(void)
  57{
  58        int ret;
  59
  60        ret = devfreq_remove_governor(&devfreq_performance);
  61        if (ret)
  62                pr_err("%s: failed remove governor %d\n", __func__, ret);
  63
  64        return;
  65}
  66module_exit(devfreq_performance_exit);
  67MODULE_LICENSE("GPL");
  68