drivers/devfreq/exynos/exynos5_bus.c - linux - Git at Google

 /*
  * Copyright (c) 2012 Samsung Electronics Co., Ltd.
  *		http://www.samsung.com/
  *
  * EXYNOS5 INT clock frequency scaling support using DEVFREQ framework
  * Based on work done by Jonghwan Choi <jhbird.choi@samsung.com>
  * Support for only EXYNOS5250 is present.
  *
  * 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/module.h>
 #include <linux/devfreq.h>
 #include <linux/io.h>
 #include <linux/pm_opp.h>
 #include <linux/slab.h>
 #include <linux/suspend.h>
 #include <linux/clk.h>
 #include <linux/delay.h>
 #include <linux/platform_device.h>
 #include <linux/pm_qos.h>
 #include <linux/regulator/consumer.h>
 #include <linux/of_address.h>
 #include <linux/of_platform.h>

 #include "exynos_ppmu.h"

 #define MAX_SAFEVOLT			1100000 /* 1.10V */
 /* Assume that the bus is saturated if the utilization is 25% */
 #define INT_BUS_SATURATION_RATIO	25

 enum int_level_idx {
 	LV_0,
 	LV_1,
 	LV_2,
 	LV_3,
 	LV_4,
 	_LV_END
 };

 enum exynos_ppmu_list {
 	PPMU_RIGHT,
 	PPMU_END,
 };

 struct busfreq_data_int {
 	struct device *dev;
 	struct devfreq *devfreq;
 	struct regulator *vdd_int;
 	struct busfreq_ppmu_data ppmu_data;
 	unsigned long curr_freq;
 	bool disabled;

 	struct notifier_block pm_notifier;
 	struct mutex lock;
 	struct pm_qos_request int_req;
 	struct clk *int_clk;
 };

 struct int_bus_opp_table {
 	unsigned int idx;
 	unsigned long clk;
 	unsigned long volt;
 };

 static struct int_bus_opp_table exynos5_int_opp_table[] = {
 	{LV_0, 266000, 1025000},
 	{LV_1, 200000, 1025000},
 	{LV_2, 160000, 1025000},
 	{LV_3, 133000, 1025000},
 	{LV_4, 100000, 1025000},
 	{0, 0, 0},
 };

 static int exynos5_int_setvolt(struct busfreq_data_int *data,
 				unsigned long volt)
 {
 	return regulator_set_voltage(data->vdd_int, volt, MAX_SAFEVOLT);
 }

 static int exynos5_busfreq_int_target(struct device *dev, unsigned long *_freq,
 			      u32 flags)
 {
 	int err = 0;
 	struct platform_device *pdev = container_of(dev, struct platform_device,
 						    dev);
 	struct busfreq_data_int *data = platform_get_drvdata(pdev);
 	struct dev_pm_opp *opp;
 	unsigned long old_freq, freq;
 	unsigned long volt;

 	rcu_read_lock();
 	opp = devfreq_recommended_opp(dev, _freq, flags);
 	if (IS_ERR(opp)) {
 		rcu_read_unlock();
 		dev_err(dev, "%s: Invalid OPP.\n", __func__);
 		return PTR_ERR(opp);
 	}

 	freq = dev_pm_opp_get_freq(opp);
 	volt = dev_pm_opp_get_voltage(opp);
 	rcu_read_unlock();

 	old_freq = data->curr_freq;

 	if (old_freq == freq)
 		return 0;

 	dev_dbg(dev, "targeting %lukHz %luuV\n", freq, volt);

 	mutex_lock(&data->lock);

 	if (data->disabled)
 		goto out;

 	if (freq > exynos5_int_opp_table[0].clk)
 		pm_qos_update_request(&data->int_req, freq * 16 / 1000);
 	else
 		pm_qos_update_request(&data->int_req, -1);

 	if (old_freq < freq)
 		err = exynos5_int_setvolt(data, volt);
 	if (err)
 		goto out;

 	err = clk_set_rate(data->int_clk, freq * 1000);

 	if (err)
 		goto out;

 	if (old_freq > freq)
 		err = exynos5_int_setvolt(data, volt);
 	if (err)
 		goto out;

 	data->curr_freq = freq;
 out:
 	mutex_unlock(&data->lock);
 	return err;
 }

 static int exynos5_int_get_dev_status(struct device *dev,
 				      struct devfreq_dev_status *stat)
 {
 	struct platform_device *pdev = container_of(dev, struct platform_device,
 						    dev);
 	struct busfreq_data_int *data = platform_get_drvdata(pdev);
 	struct busfreq_ppmu_data *ppmu_data = &data->ppmu_data;
 	int busier_dmc;

 	exynos_read_ppmu(ppmu_data);
 	busier_dmc = exynos_get_busier_ppmu(ppmu_data);

 	stat->current_frequency = data->curr_freq;

 	/* Number of cycles spent on memory access */
 	stat->busy_time = ppmu_data->ppmu[busier_dmc].count[PPMU_PMNCNT3];
 	stat->busy_time *= 100 / INT_BUS_SATURATION_RATIO;
 	stat->total_time = ppmu_data->ppmu[busier_dmc].ccnt;

 	return 0;
 }

 static struct devfreq_dev_profile exynos5_devfreq_int_profile = {
 	.initial_freq		= 160000,
 	.polling_ms		= 100,
 	.target			= exynos5_busfreq_int_target,
 	.get_dev_status		= exynos5_int_get_dev_status,
 };

 static int exynos5250_init_int_tables(struct busfreq_data_int *data)
 {
 	int i, err = 0;

 	for (i = LV_0; i < _LV_END; i++) {
 		err = dev_pm_opp_add(data->dev, exynos5_int_opp_table[i].clk,
 				exynos5_int_opp_table[i].volt);
 		if (err) {
 			dev_err(data->dev, "Cannot add opp entries.\n");
 			return err;
 		}
 	}

 	return 0;
 }

 static int exynos5_busfreq_int_pm_notifier_event(struct notifier_block *this,
 		unsigned long event, void *ptr)
 {
 	struct busfreq_data_int *data = container_of(this,
 					struct busfreq_data_int, pm_notifier);
 	struct dev_pm_opp *opp;
 	unsigned long maxfreq = ULONG_MAX;
 	unsigned long freq;
 	unsigned long volt;
 	int err = 0;

 	switch (event) {
 	case PM_SUSPEND_PREPARE:
 		/* Set Fastest and Deactivate DVFS */
 		mutex_lock(&data->lock);

 		data->disabled = true;

 		rcu_read_lock();
 		opp = dev_pm_opp_find_freq_floor(data->dev, &maxfreq);
 		if (IS_ERR(opp)) {
 			rcu_read_unlock();
 			err = PTR_ERR(opp);
 			goto unlock;
 		}
 		freq = dev_pm_opp_get_freq(opp);
 		volt = dev_pm_opp_get_voltage(opp);
 		rcu_read_unlock();

 		err = exynos5_int_setvolt(data, volt);
 		if (err)
 			goto unlock;

 		err = clk_set_rate(data->int_clk, freq * 1000);

 		if (err)
 			goto unlock;

 		data->curr_freq = freq;
 unlock:
 		mutex_unlock(&data->lock);
 		if (err)
 			return NOTIFY_BAD;
 		return NOTIFY_OK;
 	case PM_POST_RESTORE:
 	case PM_POST_SUSPEND:
 		/* Reactivate */
 		mutex_lock(&data->lock);
 		data->disabled = false;
 		mutex_unlock(&data->lock);
 		return NOTIFY_OK;
 	}

 	return NOTIFY_DONE;
 }

 static int exynos5_busfreq_int_probe(struct platform_device *pdev)
 {
 	struct busfreq_data_int *data;
 	struct busfreq_ppmu_data *ppmu_data;
 	struct dev_pm_opp *opp;
 	struct device *dev = &pdev->dev;
 	struct device_node *np;
 	unsigned long initial_freq;
 	unsigned long initial_volt;
 	int err = 0;
 	int i;

 	data = devm_kzalloc(&pdev->dev, sizeof(struct busfreq_data_int),
 				GFP_KERNEL);
 	if (data == NULL) {
 		dev_err(dev, "Cannot allocate memory.\n");
 		return -ENOMEM;
 	}

 	ppmu_data = &data->ppmu_data;
 	ppmu_data->ppmu_end = PPMU_END;
 	ppmu_data->ppmu = devm_kzalloc(dev,
 				       sizeof(struct exynos_ppmu) * PPMU_END,
 				       GFP_KERNEL);
 	if (!ppmu_data->ppmu) {
 		dev_err(dev, "Failed to allocate memory for exynos_ppmu\n");
 		return -ENOMEM;
 	}

 	np = of_find_compatible_node(NULL, NULL, "samsung,exynos5250-ppmu");
 	if (np == NULL) {
 		pr_err("Unable to find PPMU node\n");
 		return -ENOENT;
 	}

 	for (i = 0; i < ppmu_data->ppmu_end; i++) {
 		/* map PPMU memory region */
 		ppmu_data->ppmu[i].hw_base = of_iomap(np, i);
 		if (ppmu_data->ppmu[i].hw_base == NULL) {
 			dev_err(&pdev->dev, "failed to map memory region\n");
 			return -ENOMEM;
 		}
 	}
 	data->pm_notifier.notifier_call = exynos5_busfreq_int_pm_notifier_event;
 	data->dev = dev;
 	mutex_init(&data->lock);

 	err = exynos5250_init_int_tables(data);
 	if (err)
 		return err;

 	data->vdd_int = devm_regulator_get(dev, "vdd_int");
 	if (IS_ERR(data->vdd_int)) {
 		dev_err(dev, "Cannot get the regulator \"vdd_int\"\n");
 		return PTR_ERR(data->vdd_int);
 	}

 	data->int_clk = devm_clk_get(dev, "int_clk");
 	if (IS_ERR(data->int_clk)) {
 		dev_err(dev, "Cannot get clock \"int_clk\"\n");
 		return PTR_ERR(data->int_clk);
 	}

 	rcu_read_lock();
 	opp = dev_pm_opp_find_freq_floor(dev,
 			&exynos5_devfreq_int_profile.initial_freq);
 	if (IS_ERR(opp)) {
 		rcu_read_unlock();
 		dev_err(dev, "Invalid initial frequency %lu kHz.\n",
 		       exynos5_devfreq_int_profile.initial_freq);
 		return PTR_ERR(opp);
 	}
 	initial_freq = dev_pm_opp_get_freq(opp);
 	initial_volt = dev_pm_opp_get_voltage(opp);
 	rcu_read_unlock();
 	data->curr_freq = initial_freq;

 	err = clk_set_rate(data->int_clk, initial_freq * 1000);
 	if (err) {
 		dev_err(dev, "Failed to set initial frequency\n");
 		return err;
 	}

 	err = exynos5_int_setvolt(data, initial_volt);
 	if (err)
 		return err;

 	platform_set_drvdata(pdev, data);

 	busfreq_mon_reset(ppmu_data);

 	data->devfreq = devm_devfreq_add_device(dev, &exynos5_devfreq_int_profile,
 					   "simple_ondemand", NULL);
 	if (IS_ERR(data->devfreq))
 		return PTR_ERR(data->devfreq);

 	err = devm_devfreq_register_opp_notifier(dev, data->devfreq);
 	if (err < 0) {
 		dev_err(dev, "Failed to register opp notifier\n");
 		return err;
 	}

 	err = register_pm_notifier(&data->pm_notifier);
 	if (err) {
 		dev_err(dev, "Failed to setup pm notifier\n");
 		return err;
 	}

 	/* TODO: Add a new QOS class for int/mif bus */
 	pm_qos_add_request(&data->int_req, PM_QOS_NETWORK_THROUGHPUT, -1);

 	return 0;
 }

 static int exynos5_busfreq_int_remove(struct platform_device *pdev)
 {
 	struct busfreq_data_int *data = platform_get_drvdata(pdev);

 	pm_qos_remove_request(&data->int_req);
 	unregister_pm_notifier(&data->pm_notifier);

 	return 0;
 }

 #ifdef CONFIG_PM_SLEEP
 static int exynos5_busfreq_int_resume(struct device *dev)
 {
 	struct platform_device *pdev = container_of(dev, struct platform_device,
 						    dev);
 	struct busfreq_data_int *data = platform_get_drvdata(pdev);
 	struct busfreq_ppmu_data *ppmu_data = &data->ppmu_data;

 	busfreq_mon_reset(ppmu_data);
 	return 0;
 }
 static const struct dev_pm_ops exynos5_busfreq_int_pm = {
 	.resume	= exynos5_busfreq_int_resume,
 };
 #endif
 static SIMPLE_DEV_PM_OPS(exynos5_busfreq_int_pm_ops, NULL,
 			 exynos5_busfreq_int_resume);

 /* platform device pointer for exynos5 devfreq device. */
 static struct platform_device *exynos5_devfreq_pdev;

 static struct platform_driver exynos5_busfreq_int_driver = {
 	.probe		= exynos5_busfreq_int_probe,
 	.remove		= exynos5_busfreq_int_remove,
 	.driver		= {
 		.name		= "exynos5-bus-int",
 		.owner		= THIS_MODULE,
 		.pm		= &exynos5_busfreq_int_pm_ops,
 	},
 };

 static int __init exynos5_busfreq_int_init(void)
 {
 	int ret;

 	ret = platform_driver_register(&exynos5_busfreq_int_driver);
 	if (ret < 0)
 		goto out;

 	exynos5_devfreq_pdev =
 		platform_device_register_simple("exynos5-bus-int", -1, NULL, 0);
 	if (IS_ERR(exynos5_devfreq_pdev)) {
 		ret = PTR_ERR(exynos5_devfreq_pdev);
 		goto out1;
 	}

 	return 0;
 out1:
 	platform_driver_unregister(&exynos5_busfreq_int_driver);
 out:
 	return ret;
 }
 late_initcall(exynos5_busfreq_int_init);

 static void __exit exynos5_busfreq_int_exit(void)
 {
 	platform_device_unregister(exynos5_devfreq_pdev);
 	platform_driver_unregister(&exynos5_busfreq_int_driver);
 }
 module_exit(exynos5_busfreq_int_exit);

 MODULE_LICENSE("GPL");
 MODULE_DESCRIPTION("EXYNOS5 busfreq driver with devfreq framework");
	/*
	* Copyright (c) 2012 Samsung Electronics Co., Ltd.
	* http://www.samsung.com/
	*
	* EXYNOS5 INT clock frequency scaling support using DEVFREQ framework
	* Based on work done by Jonghwan Choi <jhbird.choi@samsung.com>
	* Support for only EXYNOS5250 is present.
	*
	* 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/module.h>
	#include <linux/devfreq.h>
	#include <linux/io.h>
	#include <linux/pm_opp.h>
	#include <linux/slab.h>
	#include <linux/suspend.h>
	#include <linux/clk.h>
	#include <linux/delay.h>
	#include <linux/platform_device.h>
	#include <linux/pm_qos.h>
	#include <linux/regulator/consumer.h>
	#include <linux/of_address.h>
	#include <linux/of_platform.h>

	#include "exynos_ppmu.h"

	#define MAX_SAFEVOLT 1100000 /* 1.10V */
	/* Assume that the bus is saturated if the utilization is 25% */
	#define INT_BUS_SATURATION_RATIO 25

	enum int_level_idx {
	LV_0,
	LV_1,
	LV_2,
	LV_3,
	LV_4,
	_LV_END
	};

	enum exynos_ppmu_list {
	PPMU_RIGHT,
	PPMU_END,
	};

	struct busfreq_data_int {
	struct device *dev;
	struct devfreq *devfreq;
	struct regulator *vdd_int;
	struct busfreq_ppmu_data ppmu_data;
	unsigned long curr_freq;
	bool disabled;

	struct notifier_block pm_notifier;
	struct mutex lock;
	struct pm_qos_request int_req;
	struct clk *int_clk;
	};

	struct int_bus_opp_table {
	unsigned int idx;
	unsigned long clk;
	unsigned long volt;
	};

	static struct int_bus_opp_table exynos5_int_opp_table[] = {
	{LV_0, 266000, 1025000},
	{LV_1, 200000, 1025000},
	{LV_2, 160000, 1025000},
	{LV_3, 133000, 1025000},
	{LV_4, 100000, 1025000},
	{0, 0, 0},
	};

	static int exynos5_int_setvolt(struct busfreq_data_int *data,
	unsigned long volt)
	{
	return regulator_set_voltage(data->vdd_int, volt, MAX_SAFEVOLT);
	}

	static int exynos5_busfreq_int_target(struct device dev, unsigned long _freq,
	u32 flags)
	{
	int err = 0;
	struct platform_device *pdev = container_of(dev, struct platform_device,
	dev);
	struct busfreq_data_int *data = platform_get_drvdata(pdev);
	struct dev_pm_opp *opp;
	unsigned long old_freq, freq;
	unsigned long volt;

	rcu_read_lock();
	opp = devfreq_recommended_opp(dev, _freq, flags);
	if (IS_ERR(opp)) {
	rcu_read_unlock();
	dev_err(dev, "%s: Invalid OPP.\n", __func__);
	return PTR_ERR(opp);
	}

	freq = dev_pm_opp_get_freq(opp);
	volt = dev_pm_opp_get_voltage(opp);
	rcu_read_unlock();

	old_freq = data->curr_freq;

	if (old_freq == freq)
	return 0;

	dev_dbg(dev, "targeting %lukHz %luuV\n", freq, volt);

	mutex_lock(&data->lock);

	if (data->disabled)
	goto out;

	if (freq > exynos5_int_opp_table[0].clk)
	pm_qos_update_request(&data->int_req, freq * 16 / 1000);
	else
	pm_qos_update_request(&data->int_req, -1);

	if (old_freq < freq)
	err = exynos5_int_setvolt(data, volt);
	if (err)
	goto out;

	err = clk_set_rate(data->int_clk, freq * 1000);

	if (err)
	goto out;

	if (old_freq > freq)
	err = exynos5_int_setvolt(data, volt);
	if (err)
	goto out;

	data->curr_freq = freq;
	out:
	mutex_unlock(&data->lock);
	return err;
	}

	static int exynos5_int_get_dev_status(struct device *dev,
	struct devfreq_dev_status *stat)
	{
	struct platform_device *pdev = container_of(dev, struct platform_device,
	dev);
	struct busfreq_data_int *data = platform_get_drvdata(pdev);
	struct busfreq_ppmu_data *ppmu_data = &data->ppmu_data;
	int busier_dmc;

	exynos_read_ppmu(ppmu_data);
	busier_dmc = exynos_get_busier_ppmu(ppmu_data);

	stat->current_frequency = data->curr_freq;

	/* Number of cycles spent on memory access */
	stat->busy_time = ppmu_data->ppmu[busier_dmc].count[PPMU_PMNCNT3];
	stat->busy_time *= 100 / INT_BUS_SATURATION_RATIO;
	stat->total_time = ppmu_data->ppmu[busier_dmc].ccnt;

	return 0;
	}

	static struct devfreq_dev_profile exynos5_devfreq_int_profile = {
	.initial_freq = 160000,
	.polling_ms = 100,
	.target = exynos5_busfreq_int_target,
	.get_dev_status = exynos5_int_get_dev_status,
	};

	static int exynos5250_init_int_tables(struct busfreq_data_int *data)
	{
	int i, err = 0;

	for (i = LV_0; i < _LV_END; i++) {
	err = dev_pm_opp_add(data->dev, exynos5_int_opp_table[i].clk,
	exynos5_int_opp_table[i].volt);
	if (err) {
	dev_err(data->dev, "Cannot add opp entries.\n");
	return err;
	}
	}

	return 0;
	}

	static int exynos5_busfreq_int_pm_notifier_event(struct notifier_block *this,
	unsigned long event, void *ptr)
	{
	struct busfreq_data_int *data = container_of(this,
	struct busfreq_data_int, pm_notifier);
	struct dev_pm_opp *opp;
	unsigned long maxfreq = ULONG_MAX;
	unsigned long freq;
	unsigned long volt;
	int err = 0;

	switch (event) {
	case PM_SUSPEND_PREPARE:
	/* Set Fastest and Deactivate DVFS */
	mutex_lock(&data->lock);

	data->disabled = true;

	rcu_read_lock();
	opp = dev_pm_opp_find_freq_floor(data->dev, &maxfreq);
	if (IS_ERR(opp)) {
	rcu_read_unlock();
	err = PTR_ERR(opp);
	goto unlock;
	}
	freq = dev_pm_opp_get_freq(opp);
	volt = dev_pm_opp_get_voltage(opp);
	rcu_read_unlock();

	err = exynos5_int_setvolt(data, volt);
	if (err)
	goto unlock;

	err = clk_set_rate(data->int_clk, freq * 1000);

	if (err)
	goto unlock;

	data->curr_freq = freq;
	unlock:
	mutex_unlock(&data->lock);
	if (err)
	return NOTIFY_BAD;
	return NOTIFY_OK;
	case PM_POST_RESTORE:
	case PM_POST_SUSPEND:
	/* Reactivate */
	mutex_lock(&data->lock);
	data->disabled = false;
	mutex_unlock(&data->lock);
	return NOTIFY_OK;
	}

	return NOTIFY_DONE;
	}

	static int exynos5_busfreq_int_probe(struct platform_device *pdev)
	{
	struct busfreq_data_int *data;
	struct busfreq_ppmu_data *ppmu_data;
	struct dev_pm_opp *opp;
	struct device *dev = &pdev->dev;
	struct device_node *np;
	unsigned long initial_freq;
	unsigned long initial_volt;
	int err = 0;
	int i;

	data = devm_kzalloc(&pdev->dev, sizeof(struct busfreq_data_int),
	GFP_KERNEL);
	if (data == NULL) {
	dev_err(dev, "Cannot allocate memory.\n");
	return -ENOMEM;
	}

	ppmu_data = &data->ppmu_data;
	ppmu_data->ppmu_end = PPMU_END;
	ppmu_data->ppmu = devm_kzalloc(dev,
	sizeof(struct exynos_ppmu) * PPMU_END,
	GFP_KERNEL);
	if (!ppmu_data->ppmu) {
	dev_err(dev, "Failed to allocate memory for exynos_ppmu\n");
	return -ENOMEM;
	}

	np = of_find_compatible_node(NULL, NULL, "samsung,exynos5250-ppmu");
	if (np == NULL) {
	pr_err("Unable to find PPMU node\n");
	return -ENOENT;
	}

	for (i = 0; i < ppmu_data->ppmu_end; i++) {
	/* map PPMU memory region */
	ppmu_data->ppmu[i].hw_base = of_iomap(np, i);
	if (ppmu_data->ppmu[i].hw_base == NULL) {
	dev_err(&pdev->dev, "failed to map memory region\n");
	return -ENOMEM;
	}
	}
	data->pm_notifier.notifier_call = exynos5_busfreq_int_pm_notifier_event;
	data->dev = dev;
	mutex_init(&data->lock);

	err = exynos5250_init_int_tables(data);
	if (err)
	return err;

	data->vdd_int = devm_regulator_get(dev, "vdd_int");
	if (IS_ERR(data->vdd_int)) {
	dev_err(dev, "Cannot get the regulator \"vdd_int\"\n");
	return PTR_ERR(data->vdd_int);
	}

	data->int_clk = devm_clk_get(dev, "int_clk");
	if (IS_ERR(data->int_clk)) {
	dev_err(dev, "Cannot get clock \"int_clk\"\n");
	return PTR_ERR(data->int_clk);
	}

	rcu_read_lock();
	opp = dev_pm_opp_find_freq_floor(dev,
	&exynos5_devfreq_int_profile.initial_freq);
	if (IS_ERR(opp)) {
	rcu_read_unlock();
	dev_err(dev, "Invalid initial frequency %lu kHz.\n",
	exynos5_devfreq_int_profile.initial_freq);
	return PTR_ERR(opp);
	}
	initial_freq = dev_pm_opp_get_freq(opp);
	initial_volt = dev_pm_opp_get_voltage(opp);
	rcu_read_unlock();
	data->curr_freq = initial_freq;

	err = clk_set_rate(data->int_clk, initial_freq * 1000);
	if (err) {
	dev_err(dev, "Failed to set initial frequency\n");
	return err;
	}

	err = exynos5_int_setvolt(data, initial_volt);
	if (err)
	return err;

	platform_set_drvdata(pdev, data);

	busfreq_mon_reset(ppmu_data);

	data->devfreq = devm_devfreq_add_device(dev, &exynos5_devfreq_int_profile,
	"simple_ondemand", NULL);
	if (IS_ERR(data->devfreq))
	return PTR_ERR(data->devfreq);

	err = devm_devfreq_register_opp_notifier(dev, data->devfreq);
	if (err < 0) {
	dev_err(dev, "Failed to register opp notifier\n");
	return err;
	}

	err = register_pm_notifier(&data->pm_notifier);
	if (err) {
	dev_err(dev, "Failed to setup pm notifier\n");
	return err;
	}

	/* TODO: Add a new QOS class for int/mif bus */
	pm_qos_add_request(&data->int_req, PM_QOS_NETWORK_THROUGHPUT, -1);

	return 0;
	}

	static int exynos5_busfreq_int_remove(struct platform_device *pdev)
	{
	struct busfreq_data_int *data = platform_get_drvdata(pdev);

	pm_qos_remove_request(&data->int_req);
	unregister_pm_notifier(&data->pm_notifier);

	return 0;
	}

	#ifdef CONFIG_PM_SLEEP
	static int exynos5_busfreq_int_resume(struct device *dev)
	{
	struct platform_device *pdev = container_of(dev, struct platform_device,
	dev);
	struct busfreq_data_int *data = platform_get_drvdata(pdev);
	struct busfreq_ppmu_data *ppmu_data = &data->ppmu_data;

	busfreq_mon_reset(ppmu_data);
	return 0;
	}
	static const struct dev_pm_ops exynos5_busfreq_int_pm = {
	.resume = exynos5_busfreq_int_resume,
	};
	#endif
	static SIMPLE_DEV_PM_OPS(exynos5_busfreq_int_pm_ops, NULL,
	exynos5_busfreq_int_resume);

	/* platform device pointer for exynos5 devfreq device. */
	static struct platform_device *exynos5_devfreq_pdev;

	static struct platform_driver exynos5_busfreq_int_driver = {
	.probe = exynos5_busfreq_int_probe,
	.remove = exynos5_busfreq_int_remove,
	.driver = {
	.name = "exynos5-bus-int",
	.owner = THIS_MODULE,
	.pm = &exynos5_busfreq_int_pm_ops,
	},
	};

	static int __init exynos5_busfreq_int_init(void)
	{
	int ret;

	ret = platform_driver_register(&exynos5_busfreq_int_driver);
	if (ret < 0)
	goto out;

	exynos5_devfreq_pdev =
	platform_device_register_simple("exynos5-bus-int", -1, NULL, 0);
	if (IS_ERR(exynos5_devfreq_pdev)) {
	ret = PTR_ERR(exynos5_devfreq_pdev);
	goto out1;
	}

	return 0;
	out1:
	platform_driver_unregister(&exynos5_busfreq_int_driver);
	out:
	return ret;
	}
	late_initcall(exynos5_busfreq_int_init);

	static void __exit exynos5_busfreq_int_exit(void)
	{
	platform_device_unregister(exynos5_devfreq_pdev);
	platform_driver_unregister(&exynos5_busfreq_int_driver);
	}
	module_exit(exynos5_busfreq_int_exit);

	MODULE_LICENSE("GPL");
	MODULE_DESCRIPTION("EXYNOS5 busfreq driver with devfreq framework");