devfreq-event.h
/*
* devfreq-event: a framework to provide raw data and events of devfreq devices
*
* Copyright (C) 2014 Samsung Electronics
* Author: Chanwoo Choi <cw00.choi@samsung.com>
*
* 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.
*/
#ifndef __LINUX_DEVFREQ_EVENT_H__
#define __LINUX_DEVFREQ_EVENT_H__
#include <linux/device.h>
/**
* struct devfreq_event_dev - the devfreq-event device
*
* @node : Contain the devfreq-event device that have been registered.
* @dev : the device registered by devfreq-event class. dev.parent is
* the device using devfreq-event.
* @lock : a mutex to protect accessing devfreq-event.
* @enable_count: the number of enable function have been called.
* @desc : the description for devfreq-event device.
*
* This structure contains devfreq-event device information.
*/
struct devfreq_event_dev {
struct list_head node;
struct device dev;
struct mutex lock;
u32 enable_count;
const struct devfreq_event_desc *desc;
};
/**
* struct devfreq_event_data - the devfreq-event data
*
* @load_count : load count of devfreq-event device for the given period.
* @total_count : total count of devfreq-event device for the given period.
* each count may represent a clock cycle, a time unit
* (ns/us/...), or anything the device driver wants.
* Generally, utilization is load_count / total_count.
*
* This structure contains the data of devfreq-event device for polling period.
*/
struct devfreq_event_data {
unsigned long load_count;
unsigned long total_count;
};
/**
* struct devfreq_event_ops - the operations of devfreq-event device
*
* @enable : Enable the devfreq-event device.
* @disable : Disable the devfreq-event device.
* @reset : Reset all setting of the devfreq-event device.
* @set_event : Set the specific event type for the devfreq-event device.
* @get_event : Get the result of the devfreq-event devie with specific
* event type.
*
* This structure contains devfreq-event device operations which can be
* implemented by devfreq-event device drivers.
*/
struct devfreq_event_ops {
/* Optional functions */
int (*enable)(struct devfreq_event_dev *edev);
int (*disable)(struct devfreq_event_dev *edev);
int (*reset)(struct devfreq_event_dev *edev);
/* Mandatory functions */
int (*set_event)(struct devfreq_event_dev *edev);
int (*get_event)(struct devfreq_event_dev *edev,
struct devfreq_event_data *edata);
};
/**
* struct devfreq_event_desc - the descriptor of devfreq-event device
*
* @name : the name of devfreq-event device.
* @driver_data : the private data for devfreq-event driver.
* @ops : the operation to control devfreq-event device.
*
* Each devfreq-event device is described with a this structure.
* This structure contains the various data for devfreq-event device.
*/
struct devfreq_event_desc {
const char *name;
void *driver_data;
const struct devfreq_event_ops *ops;
};
#if defined(CONFIG_PM_DEVFREQ_EVENT)
extern int devfreq_event_enable_edev(struct devfreq_event_dev *edev);
extern int devfreq_event_disable_edev(struct devfreq_event_dev *edev);
extern bool devfreq_event_is_enabled(struct devfreq_event_dev *edev);
extern int devfreq_event_set_event(struct devfreq_event_dev *edev);
extern int devfreq_event_get_event(struct devfreq_event_dev *edev,
struct devfreq_event_data *edata);
extern int devfreq_event_reset_event(struct devfreq_event_dev *edev);
extern struct devfreq_event_dev *devfreq_event_get_edev_by_phandle(
struct device *dev, int index);
extern int devfreq_event_get_edev_count(struct device *dev);
extern struct devfreq_event_dev *devfreq_event_add_edev(struct device *dev,
struct devfreq_event_desc *desc);
extern int devfreq_event_remove_edev(struct devfreq_event_dev *edev);
extern struct devfreq_event_dev *devm_devfreq_event_add_edev(struct device *dev,
struct devfreq_event_desc *desc);
extern void devm_devfreq_event_remove_edev(struct device *dev,
struct devfreq_event_dev *edev);
static inline void *devfreq_event_get_drvdata(struct devfreq_event_dev *edev)
{
return edev->desc->driver_data;
}
#else
static inline int devfreq_event_enable_edev(struct devfreq_event_dev *edev)
{
return -EINVAL;
}
static inline int devfreq_event_disable_edev(struct devfreq_event_dev *edev)
{
return -EINVAL;
}
static inline bool devfreq_event_is_enabled(struct devfreq_event_dev *edev)
{
return false;
}
static inline int devfreq_event_set_event(struct devfreq_event_dev *edev)
{
return -EINVAL;
}
static inline int devfreq_event_get_event(struct devfreq_event_dev *edev,
struct devfreq_event_data *edata)
{
return -EINVAL;
}
static inline int devfreq_event_reset_event(struct devfreq_event_dev *edev)
{
return -EINVAL;
}
static inline void *devfreq_event_get_drvdata(struct devfreq_event_dev *edev)
{
return ERR_PTR(-EINVAL);
}
static inline struct devfreq_event_dev *devfreq_event_get_edev_by_phandle(
struct device *dev, int index)
{
return ERR_PTR(-EINVAL);
}
static inline int devfreq_event_get_edev_count(struct device *dev)
{
return -EINVAL;
}
static inline struct devfreq_event_dev *devfreq_event_add_edev(struct device *dev,
struct devfreq_event_desc *desc)
{
return ERR_PTR(-EINVAL);
}
static inline int devfreq_event_remove_edev(struct devfreq_event_dev *edev)
{
return -EINVAL;
}
static inline struct devfreq_event_dev *devm_devfreq_event_add_edev(
struct device *dev,
struct devfreq_event_desc *desc)
{
return ERR_PTR(-EINVAL);
}
static inline void devm_devfreq_event_remove_edev(struct device *dev,
struct devfreq_event_dev *edev)
{
}
static inline void *devfreq_event_get_drvdata(struct devfreq_event_dev *edev)
{
return NULL;
}
#endif /* CONFIG_PM_DEVFREQ_EVENT */
#endif /* __LINUX_DEVFREQ_EVENT_H__ */