[deliverable/linux.git] / drivers / cpufreq / cpufreq_conservative.c

/*
 *  drivers/cpufreq/cpufreq_conservative.c
 *
 *  Copyright (C)  2001 Russell King
 *            (C)  2003 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>.
 *                      Jun Nakajima <jun.nakajima@intel.com>
 *            (C)  2009 Alexander Clouter <alex@digriz.org.uk>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <linux/cpufreq.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/kernel_stat.h>
#include <linux/kobject.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/notifier.h>
#include <linux/percpu-defs.h>
#include <linux/sysfs.h>
#include <linux/types.h>

#include "cpufreq_governor.h"

/* Conservative governor macors */
#define DEF_FREQUENCY_UP_THRESHOLD		(80)
#define DEF_FREQUENCY_DOWN_THRESHOLD		(20)
#define DEF_SAMPLING_DOWN_FACTOR		(1)
#define MAX_SAMPLING_DOWN_FACTOR		(10)

static struct dbs_data cs_dbs_data;
static DEFINE_PER_CPU(struct cs_cpu_dbs_info_s, cs_cpu_dbs_info);

static struct cs_dbs_tuners cs_tuners = {
	.up_threshold = DEF_FREQUENCY_UP_THRESHOLD,
	.down_threshold = DEF_FREQUENCY_DOWN_THRESHOLD,
	.sampling_down_factor = DEF_SAMPLING_DOWN_FACTOR,
	.ignore_nice = 0,
	.freq_step = 5,
};

/*
 * Every sampling_rate, we check, if current idle time is less than 20%
 * (default), then we try to increase frequency Every sampling_rate *
 * sampling_down_factor, we check, if current idle time is more than 80%, then
 * we try to decrease frequency
 *
 * Any frequency increase takes it to the maximum frequency. Frequency reduction
 * happens at minimum steps of 5% (default) of maximum frequency
 */
static void cs_check_cpu(int cpu, unsigned int load)
{
	struct cs_cpu_dbs_info_s *dbs_info = &per_cpu(cs_cpu_dbs_info, cpu);
	struct cpufreq_policy *policy = dbs_info->cdbs.cur_policy;
	unsigned int freq_target;

	/*
	 * break out if we 'cannot' reduce the speed as the user might
	 * want freq_step to be zero
	 */
	if (cs_tuners.freq_step == 0)
		return;

	/* Check for frequency increase */
	if (load > cs_tuners.up_threshold) {
		dbs_info->down_skip = 0;

		/* if we are already at full speed then break out early */
		if (dbs_info->requested_freq == policy->max)
			return;

		freq_target = (cs_tuners.freq_step * policy->max) / 100;

		/* max freq cannot be less than 100. But who knows.... */
		if (unlikely(freq_target == 0))
			freq_target = 5;

		dbs_info->requested_freq += freq_target;
		if (dbs_info->requested_freq > policy->max)
			dbs_info->requested_freq = policy->max;

		__cpufreq_driver_target(policy, dbs_info->requested_freq,
			CPUFREQ_RELATION_H);
		return;
	}

	/*
	 * The optimal frequency is the frequency that is the lowest that can
	 * support the current CPU usage without triggering the up policy. To be
	 * safe, we focus 10 points under the threshold.
	 */
	if (load < (cs_tuners.down_threshold - 10)) {
		freq_target = (cs_tuners.freq_step * policy->max) / 100;

		dbs_info->requested_freq -= freq_target;
		if (dbs_info->requested_freq < policy->min)
			dbs_info->requested_freq = policy->min;

		/*
		 * if we cannot reduce the frequency anymore, break out early
		 */
		if (policy->cur == policy->min)
			return;

		__cpufreq_driver_target(policy, dbs_info->requested_freq,
				CPUFREQ_RELATION_H);
		return;
	}
}

static void cs_dbs_timer(struct work_struct *work)
{
	struct cs_cpu_dbs_info_s *dbs_info = container_of(work,
			struct cs_cpu_dbs_info_s, cdbs.work.work);
	unsigned int cpu = dbs_info->cdbs.cpu;
	int delay = delay_for_sampling_rate(cs_tuners.sampling_rate);

	mutex_lock(&dbs_info->cdbs.timer_mutex);

	dbs_check_cpu(&cs_dbs_data, cpu);

	schedule_delayed_work_on(cpu, &dbs_info->cdbs.work, delay);
	mutex_unlock(&dbs_info->cdbs.timer_mutex);
}

static int dbs_cpufreq_notifier(struct notifier_block *nb, unsigned long val,
		void *data)
{
	struct cpufreq_freqs *freq = data;
	struct cs_cpu_dbs_info_s *dbs_info =
					&per_cpu(cs_cpu_dbs_info, freq->cpu);
	struct cpufreq_policy *policy;

	if (!dbs_info->enable)
		return 0;

	policy = dbs_info->cdbs.cur_policy;

	/*
	 * we only care if our internally tracked freq moves outside the 'valid'
	 * ranges of freqency available to us otherwise we do not change it
	*/
	if (dbs_info->requested_freq > policy->max
			|| dbs_info->requested_freq < policy->min)
		dbs_info->requested_freq = freq->new;

	return 0;
}

/************************** sysfs interface ************************/
static ssize_t show_sampling_rate_min(struct kobject *kobj,
				      struct attribute *attr, char *buf)
{
	return sprintf(buf, "%u\n", cs_dbs_data.min_sampling_rate);
}

static ssize_t store_sampling_down_factor(struct kobject *a,
					  struct attribute *b,
					  const char *buf, size_t count)
{
	unsigned int input;
	int ret;
	ret = sscanf(buf, "%u", &input);

	if (ret != 1 || input > MAX_SAMPLING_DOWN_FACTOR || input < 1)
		return -EINVAL;

	cs_tuners.sampling_down_factor = input;
	return count;
}

static ssize_t store_sampling_rate(struct kobject *a, struct attribute *b,
				   const char *buf, size_t count)
{
	unsigned int input;
	int ret;
	ret = sscanf(buf, "%u", &input);

	if (ret != 1)
		return -EINVAL;

	cs_tuners.sampling_rate = max(input, cs_dbs_data.min_sampling_rate);
	return count;
}

static ssize_t store_up_threshold(struct kobject *a, struct attribute *b,
				  const char *buf, size_t count)
{
	unsigned int input;
	int ret;
	ret = sscanf(buf, "%u", &input);

	if (ret != 1 || input > 100 || input <= cs_tuners.down_threshold)
		return -EINVAL;

	cs_tuners.up_threshold = input;
	return count;
}

static ssize_t store_down_threshold(struct kobject *a, struct attribute *b,
				    const char *buf, size_t count)
{
	unsigned int input;
	int ret;
	ret = sscanf(buf, "%u", &input);

	/* cannot be lower than 11 otherwise freq will not fall */
	if (ret != 1 || input < 11 || input > 100 ||
			input >= cs_tuners.up_threshold)
		return -EINVAL;

	cs_tuners.down_threshold = input;
	return count;
}

static ssize_t store_ignore_nice_load(struct kobject *a, struct attribute *b,
				      const char *buf, size_t count)
{
	unsigned int input, j;
	int ret;

	ret = sscanf(buf, "%u", &input);
	if (ret != 1)
		return -EINVAL;

	if (input > 1)
		input = 1;

	if (input == cs_tuners.ignore_nice) /* nothing to do */
		return count;

	cs_tuners.ignore_nice = input;

	/* we need to re-evaluate prev_cpu_idle */
	for_each_online_cpu(j) {
		struct cs_cpu_dbs_info_s *dbs_info;
		dbs_info = &per_cpu(cs_cpu_dbs_info, j);
		dbs_info->cdbs.prev_cpu_idle = get_cpu_idle_time(j,
						&dbs_info->cdbs.prev_cpu_wall);
		if (cs_tuners.ignore_nice)
			dbs_info->cdbs.prev_cpu_nice =
				kcpustat_cpu(j).cpustat[CPUTIME_NICE];
	}
	return count;
}

static ssize_t store_freq_step(struct kobject *a, struct attribute *b,
			       const char *buf, size_t count)
{
	unsigned int input;
	int ret;
	ret = sscanf(buf, "%u", &input);

	if (ret != 1)
		return -EINVAL;

	if (input > 100)
		input = 100;

	/*
	 * no need to test here if freq_step is zero as the user might actually
	 * want this, they would be crazy though :)
	 */
	cs_tuners.freq_step = input;
	return count;
}

show_one(cs, sampling_rate, sampling_rate);
show_one(cs, sampling_down_factor, sampling_down_factor);
show_one(cs, up_threshold, up_threshold);
show_one(cs, down_threshold, down_threshold);
show_one(cs, ignore_nice_load, ignore_nice);
show_one(cs, freq_step, freq_step);

define_one_global_rw(sampling_rate);
define_one_global_rw(sampling_down_factor);
define_one_global_rw(up_threshold);
define_one_global_rw(down_threshold);
define_one_global_rw(ignore_nice_load);
define_one_global_rw(freq_step);
define_one_global_ro(sampling_rate_min);

static struct attribute *dbs_attributes[] = {
	&sampling_rate_min.attr,
	&sampling_rate.attr,
	&sampling_down_factor.attr,
	&up_threshold.attr,
	&down_threshold.attr,
	&ignore_nice_load.attr,
	&freq_step.attr,
	NULL
};

static struct attribute_group cs_attr_group = {
	.attrs = dbs_attributes,
	.name = "conservative",
};

/************************** sysfs end ************************/

define_get_cpu_dbs_routines(cs_cpu_dbs_info);

static struct notifier_block cs_cpufreq_notifier_block = {
	.notifier_call = dbs_cpufreq_notifier,
};

static struct cs_ops cs_ops = {
	.notifier_block = &cs_cpufreq_notifier_block,
};

static struct dbs_data cs_dbs_data = {
	.governor = GOV_CONSERVATIVE,
	.attr_group = &cs_attr_group,
	.tuners = &cs_tuners,
	.get_cpu_cdbs = get_cpu_cdbs,
	.get_cpu_dbs_info_s = get_cpu_dbs_info_s,
	.gov_dbs_timer = cs_dbs_timer,
	.gov_check_cpu = cs_check_cpu,
	.gov_ops = &cs_ops,
};

static int cs_cpufreq_governor_dbs(struct cpufreq_policy *policy,
				   unsigned int event)
{
	return cpufreq_governor_dbs(&cs_dbs_data, policy, event);
}

#ifndef CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE
static
#endif
struct cpufreq_governor cpufreq_gov_conservative = {
	.name			= "conservative",
	.governor		= cs_cpufreq_governor_dbs,
	.max_transition_latency	= TRANSITION_LATENCY_LIMIT,
	.owner			= THIS_MODULE,
};

static int __init cpufreq_gov_dbs_init(void)
{
	mutex_init(&cs_dbs_data.mutex);
	return cpufreq_register_governor(&cpufreq_gov_conservative);
}

static void __exit cpufreq_gov_dbs_exit(void)
{
	cpufreq_unregister_governor(&cpufreq_gov_conservative);
}

MODULE_AUTHOR("Alexander Clouter <alex@digriz.org.uk>");
MODULE_DESCRIPTION("'cpufreq_conservative' - A dynamic cpufreq governor for "
		"Low Latency Frequency Transition capable processors "
		"optimised for use in a battery environment");
MODULE_LICENSE("GPL");

#ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE
fs_initcall(cpufreq_gov_dbs_init);
#else
module_init(cpufreq_gov_dbs_init);
#endif
module_exit(cpufreq_gov_dbs_exit);
Commit	Line	Data
b9170836 DJ	1	/*
	2	* drivers/cpufreq/cpufreq_conservative.c
	3	*
	4	* Copyright (C) 2001 Russell King
	5	* (C) 2003 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>.
	6	* Jun Nakajima <jun.nakajima@intel.com>
11a80a9c	7	* (C) 2009 Alexander Clouter <alex@digriz.org.uk>
b9170836 DJ	8	*
	9	* This program is free software; you can redistribute it and/or modify
	10	* it under the terms of the GNU General Public License version 2 as
	11	* published by the Free Software Foundation.
	12	*/
	13
b9170836	14	#include <linux/cpufreq.h>
4471a34f VK	15	#include <linux/init.h>
4471a34f VK	16	#include <linux/kernel.h>
b9170836	17	#include <linux/kernel_stat.h>
4471a34f VK	18	#include <linux/kobject.h>
4471a34f VK	19	#include <linux/module.h>
3fc54d37	20	#include <linux/mutex.h>
4471a34f VK	21	#include <linux/notifier.h>
	22	#include <linux/percpu-defs.h>
	23	#include <linux/sysfs.h>
	24	#include <linux/types.h>
8e677ce8	25
4471a34f	26	#include "cpufreq_governor.h"
b9170836	27
4471a34f	28	/* Conservative governor macors */
b9170836	29	#define DEF_FREQUENCY_UP_THRESHOLD (80)
b9170836	30	#define DEF_FREQUENCY_DOWN_THRESHOLD (20)
2c906b31 AC	31	#define DEF_SAMPLING_DOWN_FACTOR (1)
2c906b31 AC	32	#define MAX_SAMPLING_DOWN_FACTOR (10)
b9170836	33
4471a34f VK	34	static struct dbs_data cs_dbs_data;
4471a34f VK	35	static DEFINE_PER_CPU(struct cs_cpu_dbs_info_s, cs_cpu_dbs_info);
b9170836	36
4471a34f	37	static struct cs_dbs_tuners cs_tuners = {
18a7247d DJ	38	.up_threshold = DEF_FREQUENCY_UP_THRESHOLD,
	39	.down_threshold = DEF_FREQUENCY_DOWN_THRESHOLD,
	40	.sampling_down_factor = DEF_SAMPLING_DOWN_FACTOR,
	41	.ignore_nice = 0,
	42	.freq_step = 5,
b9170836 DJ	43	};
b9170836 DJ	44
4471a34f VK	45	/*
	46	* Every sampling_rate, we check, if current idle time is less than 20%
	47	* (default), then we try to increase frequency Every sampling_rate *
	48	* sampling_down_factor, we check, if current idle time is more than 80%, then
	49	* we try to decrease frequency
	50	*
	51	* Any frequency increase takes it to the maximum frequency. Frequency reduction
	52	* happens at minimum steps of 5% (default) of maximum frequency
	53	*/
	54	static void cs_check_cpu(int cpu, unsigned int load)
a8d7c3bc	55	{
4471a34f VK	56	struct cs_cpu_dbs_info_s *dbs_info = &per_cpu(cs_cpu_dbs_info, cpu);
	57	struct cpufreq_policy *policy = dbs_info->cdbs.cur_policy;
	58	unsigned int freq_target;
	59
	60	/*
	61	* break out if we 'cannot' reduce the speed as the user might
	62	* want freq_step to be zero
	63	*/
	64	if (cs_tuners.freq_step == 0)
	65	return;
	66
	67	/* Check for frequency increase */
	68	if (load > cs_tuners.up_threshold) {
	69	dbs_info->down_skip = 0;
	70
	71	/* if we are already at full speed then break out early */
	72	if (dbs_info->requested_freq == policy->max)
	73	return;
	74
	75	freq_target = (cs_tuners.freq_step * policy->max) / 100;
	76
	77	/* max freq cannot be less than 100. But who knows.... */
	78	if (unlikely(freq_target == 0))
	79	freq_target = 5;
	80
	81	dbs_info->requested_freq += freq_target;
	82	if (dbs_info->requested_freq > policy->max)
	83	dbs_info->requested_freq = policy->max;
a8d7c3bc	84
4471a34f VK	85	__cpufreq_driver_target(policy, dbs_info->requested_freq,
	86	CPUFREQ_RELATION_H);
	87	return;
	88	}
	89
	90	/*
	91	* The optimal frequency is the frequency that is the lowest that can
	92	* support the current CPU usage without triggering the up policy. To be
	93	* safe, we focus 10 points under the threshold.
	94	*/
	95	if (load < (cs_tuners.down_threshold - 10)) {
	96	freq_target = (cs_tuners.freq_step * policy->max) / 100;
	97
	98	dbs_info->requested_freq -= freq_target;
	99	if (dbs_info->requested_freq < policy->min)
	100	dbs_info->requested_freq = policy->min;
	101
	102	/*
	103	* if we cannot reduce the frequency anymore, break out early
	104	*/
	105	if (policy->cur == policy->min)
	106	return;
	107
	108	__cpufreq_driver_target(policy, dbs_info->requested_freq,
	109	CPUFREQ_RELATION_H);
	110	return;
	111	}
	112	}
	113
	114	static void cs_dbs_timer(struct work_struct *work)
	115	{
	116	struct cs_cpu_dbs_info_s *dbs_info = container_of(work,
	117	struct cs_cpu_dbs_info_s, cdbs.work.work);
	118	unsigned int cpu = dbs_info->cdbs.cpu;
	119	int delay = delay_for_sampling_rate(cs_tuners.sampling_rate);
	120
	121	mutex_lock(&dbs_info->cdbs.timer_mutex);
	122
	123	dbs_check_cpu(&cs_dbs_data, cpu);
	124
	125	schedule_delayed_work_on(cpu, &dbs_info->cdbs.work, delay);
	126	mutex_unlock(&dbs_info->cdbs.timer_mutex);
	127	}
	128
	129	static int dbs_cpufreq_notifier(struct notifier_block *nb, unsigned long val,
	130	void *data)
	131	{
	132	struct cpufreq_freqs *freq = data;
	133	struct cs_cpu_dbs_info_s *dbs_info =
	134	&per_cpu(cs_cpu_dbs_info, freq->cpu);
f407a08b AC	135	struct cpufreq_policy *policy;
f407a08b AC	136
4471a34f	137	if (!dbs_info->enable)
a8d7c3bc EO	138	return 0;
a8d7c3bc EO	139
4471a34f	140	policy = dbs_info->cdbs.cur_policy;
f407a08b AC	141
f407a08b AC	142	/*
4471a34f VK	143	* we only care if our internally tracked freq moves outside the 'valid'
4471a34f VK	144	* ranges of freqency available to us otherwise we do not change it
f407a08b	145	*/
4471a34f VK	146	if (dbs_info->requested_freq > policy->max
	147	\|\| dbs_info->requested_freq < policy->min)
	148	dbs_info->requested_freq = freq->new;
a8d7c3bc EO	149
	150	return 0;
	151	}
	152
b9170836	153	/************************ sysfs interface **********************/
49b015ce TR	154	static ssize_t show_sampling_rate_min(struct kobject *kobj,
49b015ce TR	155	struct attribute attr, char buf)
b9170836	156	{
4471a34f	157	return sprintf(buf, "%u\n", cs_dbs_data.min_sampling_rate);
b9170836 DJ	158	}
b9170836 DJ	159
49b015ce TR	160	static ssize_t store_sampling_down_factor(struct kobject *a,
	161	struct attribute *b,
	162	const char *buf, size_t count)
b9170836 DJ	163	{
	164	unsigned int input;
	165	int ret;
9acef487	166	ret = sscanf(buf, "%u", &input);
8e677ce8	167
2c906b31	168	if (ret != 1 \|\| input > MAX_SAMPLING_DOWN_FACTOR \|\| input < 1)
b9170836 DJ	169	return -EINVAL;
b9170836 DJ	170
4471a34f	171	cs_tuners.sampling_down_factor = input;
b9170836 DJ	172	return count;
	173	}
	174
49b015ce TR	175	static ssize_t store_sampling_rate(struct kobject a, struct attribute b,
49b015ce TR	176	const char *buf, size_t count)
b9170836 DJ	177	{
	178	unsigned int input;
	179	int ret;
9acef487	180	ret = sscanf(buf, "%u", &input);
b9170836	181
8e677ce8	182	if (ret != 1)
b9170836	183	return -EINVAL;
8e677ce8	184
4471a34f	185	cs_tuners.sampling_rate = max(input, cs_dbs_data.min_sampling_rate);
b9170836 DJ	186	return count;
	187	}
	188
49b015ce TR	189	static ssize_t store_up_threshold(struct kobject a, struct attribute b,
49b015ce TR	190	const char *buf, size_t count)
b9170836 DJ	191	{
	192	unsigned int input;
	193	int ret;
9acef487	194	ret = sscanf(buf, "%u", &input);
b9170836	195
4471a34f	196	if (ret != 1 \|\| input > 100 \|\| input <= cs_tuners.down_threshold)
b9170836	197	return -EINVAL;
b9170836	198
4471a34f	199	cs_tuners.up_threshold = input;
b9170836 DJ	200	return count;
	201	}
	202
49b015ce TR	203	static ssize_t store_down_threshold(struct kobject a, struct attribute b,
49b015ce TR	204	const char *buf, size_t count)
b9170836 DJ	205	{
	206	unsigned int input;
	207	int ret;
9acef487	208	ret = sscanf(buf, "%u", &input);
b9170836	209
8e677ce8 AC	210	/* cannot be lower than 11 otherwise freq will not fall */
8e677ce8 AC	211	if (ret != 1 \|\| input < 11 \|\| input > 100 \|\|
4471a34f	212	input >= cs_tuners.up_threshold)
b9170836	213	return -EINVAL;
b9170836	214
4471a34f	215	cs_tuners.down_threshold = input;
b9170836 DJ	216	return count;
	217	}
	218
49b015ce TR	219	static ssize_t store_ignore_nice_load(struct kobject a, struct attribute b,
49b015ce TR	220	const char *buf, size_t count)
b9170836	221	{
4471a34f	222	unsigned int input, j;
b9170836 DJ	223	int ret;
b9170836 DJ	224
18a7247d DJ	225	ret = sscanf(buf, "%u", &input);
18a7247d DJ	226	if (ret != 1)
b9170836 DJ	227	return -EINVAL;
b9170836 DJ	228
18a7247d	229	if (input > 1)
b9170836	230	input = 1;
18a7247d	231
4471a34f	232	if (input == cs_tuners.ignore_nice) /* nothing to do */
b9170836	233	return count;
326c86de	234
4471a34f	235	cs_tuners.ignore_nice = input;
b9170836	236
8e677ce8	237	/* we need to re-evaluate prev_cpu_idle */
dac1c1a5	238	for_each_online_cpu(j) {
4471a34f	239	struct cs_cpu_dbs_info_s *dbs_info;
245b2e70	240	dbs_info = &per_cpu(cs_cpu_dbs_info, j);
4471a34f VK	241	dbs_info->cdbs.prev_cpu_idle = get_cpu_idle_time(j,
	242	&dbs_info->cdbs.prev_cpu_wall);
	243	if (cs_tuners.ignore_nice)
	244	dbs_info->cdbs.prev_cpu_nice =
	245	kcpustat_cpu(j).cpustat[CPUTIME_NICE];
b9170836	246	}
b9170836 DJ	247	return count;
	248	}
	249
49b015ce TR	250	static ssize_t store_freq_step(struct kobject a, struct attribute b,
49b015ce TR	251	const char *buf, size_t count)
b9170836 DJ	252	{
	253	unsigned int input;
	254	int ret;
18a7247d	255	ret = sscanf(buf, "%u", &input);
b9170836	256
18a7247d	257	if (ret != 1)
b9170836 DJ	258	return -EINVAL;
b9170836 DJ	259
18a7247d	260	if (input > 100)
b9170836	261	input = 100;
18a7247d	262
4471a34f VK	263	/*
	264	* no need to test here if freq_step is zero as the user might actually
	265	* want this, they would be crazy though :)
	266	*/
	267	cs_tuners.freq_step = input;
b9170836 DJ	268	return count;
	269	}
	270
4471a34f VK	271	show_one(cs, sampling_rate, sampling_rate);
	272	show_one(cs, sampling_down_factor, sampling_down_factor);
	273	show_one(cs, up_threshold, up_threshold);
	274	show_one(cs, down_threshold, down_threshold);
	275	show_one(cs, ignore_nice_load, ignore_nice);
	276	show_one(cs, freq_step, freq_step);
	277
6dad2a29 BP	278	define_one_global_rw(sampling_rate);
	279	define_one_global_rw(sampling_down_factor);
	280	define_one_global_rw(up_threshold);
	281	define_one_global_rw(down_threshold);
	282	define_one_global_rw(ignore_nice_load);
	283	define_one_global_rw(freq_step);
4471a34f	284	define_one_global_ro(sampling_rate_min);
b9170836	285
9acef487	286	static struct attribute *dbs_attributes[] = {
b9170836 DJ	287	&sampling_rate_min.attr,
	288	&sampling_rate.attr,
	289	&sampling_down_factor.attr,
	290	&up_threshold.attr,
	291	&down_threshold.attr,
001893cd	292	&ignore_nice_load.attr,
b9170836 DJ	293	&freq_step.attr,
	294	NULL
	295	};
	296
4471a34f	297	static struct attribute_group cs_attr_group = {
b9170836 DJ	298	.attrs = dbs_attributes,
	299	.name = "conservative",
	300	};
	301
	302	/************************ sysfs end **********************/
	303
4471a34f	304	define_get_cpu_dbs_routines(cs_cpu_dbs_info);
8e677ce8	305
4471a34f VK	306	static struct notifier_block cs_cpufreq_notifier_block = {
	307	.notifier_call = dbs_cpufreq_notifier,
	308	};
8e677ce8	309
4471a34f VK	310	static struct cs_ops cs_ops = {
	311	.notifier_block = &cs_cpufreq_notifier_block,
	312	};
b9170836	313
4471a34f VK	314	static struct dbs_data cs_dbs_data = {
	315	.governor = GOV_CONSERVATIVE,
	316	.attr_group = &cs_attr_group,
	317	.tuners = &cs_tuners,
	318	.get_cpu_cdbs = get_cpu_cdbs,
	319	.get_cpu_dbs_info_s = get_cpu_dbs_info_s,
	320	.gov_dbs_timer = cs_dbs_timer,
	321	.gov_check_cpu = cs_check_cpu,
	322	.gov_ops = &cs_ops,
	323	};
b9170836	324
4471a34f	325	static int cs_cpufreq_governor_dbs(struct cpufreq_policy *policy,
b9170836 DJ	326	unsigned int event)
b9170836 DJ	327	{
4471a34f	328	return cpufreq_governor_dbs(&cs_dbs_data, policy, event);
b9170836 DJ	329	}
b9170836 DJ	330
c4d14bc0 SW	331	#ifndef CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE
	332	static
	333	#endif
1c256245 TR	334	struct cpufreq_governor cpufreq_gov_conservative = {
1c256245 TR	335	.name = "conservative",
4471a34f	336	.governor = cs_cpufreq_governor_dbs,
1c256245 TR	337	.max_transition_latency = TRANSITION_LATENCY_LIMIT,
1c256245 TR	338	.owner = THIS_MODULE,
b9170836 DJ	339	};
	340
	341	static int __init cpufreq_gov_dbs_init(void)
	342	{
4471a34f	343	mutex_init(&cs_dbs_data.mutex);
57df5573	344	return cpufreq_register_governor(&cpufreq_gov_conservative);
b9170836 DJ	345	}
	346
	347	static void __exit cpufreq_gov_dbs_exit(void)
	348	{
1c256245	349	cpufreq_unregister_governor(&cpufreq_gov_conservative);
b9170836 DJ	350	}
b9170836 DJ	351
11a80a9c	352	MODULE_AUTHOR("Alexander Clouter <alex@digriz.org.uk>");
9acef487	353	MODULE_DESCRIPTION("'cpufreq_conservative' - A dynamic cpufreq governor for "
b9170836 DJ	354	"Low Latency Frequency Transition capable processors "
b9170836 DJ	355	"optimised for use in a battery environment");
9acef487	356	MODULE_LICENSE("GPL");
b9170836	357
6915719b JW	358	#ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE
	359	fs_initcall(cpufreq_gov_dbs_init);
	360	#else
b9170836	361	module_init(cpufreq_gov_dbs_init);
6915719b	362	#endif
b9170836	363	module_exit(cpufreq_gov_dbs_exit);