devfreq-event.c | Explore in Territory

// SPDX-License-Identifier: GPL-2.0-only
/*
 * devfreq-event: a framework to provide raw data and events of devfreq devices
 *
 * Copyright (C) 2015 Samsung Electronics
 * Author: Chanwoo Choi <[email protected]>
 *
 * This driver is based on drivers/devfreq/devfreq.c.
 */

#include <linux/devfreq-event.h>
#include <linux/kernel.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/export.h>
#include <linux/slab.h>
#include <linux/list.h>
#include <linux/of.h>

static struct class *devfreq_event_class;

/* The list of all devfreq event list */
static LIST_HEAD(devfreq_event_list);
static DEFINE_MUTEX(devfreq_event_list_lock);

#define to_devfreq_event(DEV) …

/**
 * devfreq_event_enable_edev() - Enable the devfreq-event dev and increase
 *				 the enable_count of devfreq-event dev.
 * @edev	: the devfreq-event device
 *
 * Note that this function increase the enable_count and enable the
 * devfreq-event device. The devfreq-event device should be enabled before
 * using it by devfreq device.
 */
int devfreq_event_enable_edev(struct devfreq_event_dev *edev)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * devfreq_event_disable_edev() - Disable the devfreq-event dev and decrease
 *				  the enable_count of the devfreq-event dev.
 * @edev	: the devfreq-event device
 *
 * Note that this function decrease the enable_count and disable the
 * devfreq-event device. After the devfreq-event device is disabled,
 * devfreq device can't use the devfreq-event device for get/set/reset
 * operations.
 */
int devfreq_event_disable_edev(struct devfreq_event_dev *edev)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * devfreq_event_is_enabled() - Check whether devfreq-event dev is enabled or
 *				not.
 * @edev	: the devfreq-event device
 *
 * Note that this function check whether devfreq-event dev is enabled or not.
 * If return true, the devfreq-event dev is enabeld. If return false, the
 * devfreq-event dev is disabled.
 */
bool devfreq_event_is_enabled(struct devfreq_event_dev *edev)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * devfreq_event_set_event() - Set event to devfreq-event dev to start.
 * @edev	: the devfreq-event device
 *
 * Note that this function set the event to the devfreq-event device to start
 * for getting the event data which could be various event type.
 */
int devfreq_event_set_event(struct devfreq_event_dev *edev)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * devfreq_event_get_event() - Get {load|total}_count from devfreq-event dev.
 * @edev	: the devfreq-event device
 * @edata	: the calculated data of devfreq-event device
 *
 * Note that this function get the calculated event data from devfreq-event dev
 * after stoping the progress of whole sequence of devfreq-event dev.
 */
int devfreq_event_get_event(struct devfreq_event_dev *edev,
			    struct devfreq_event_data *edata)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * devfreq_event_reset_event() - Reset all opeations of devfreq-event dev.
 * @edev	: the devfreq-event device
 *
 * Note that this function stop all operations of devfreq-event dev and reset
 * the current event data to make the devfreq-event device into initial state.
 */
int devfreq_event_reset_event(struct devfreq_event_dev *edev)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * devfreq_event_get_edev_by_phandle() - Get the devfreq-event dev from
 *					 devicetree.
 * @dev		: the pointer to the given device
 * @phandle_name: name of property holding a phandle value
 * @index	: the index into list of devfreq-event device
 *
 * Note that this function return the pointer of devfreq-event device.
 */
struct devfreq_event_dev *devfreq_event_get_edev_by_phandle(struct device *dev,
					const char *phandle_name, int index)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * devfreq_event_get_edev_count() - Get the count of devfreq-event dev
 * @dev		: the pointer to the given device
 * @phandle_name: name of property holding a phandle value
 *
 * Note that this function return the count of devfreq-event devices.
 */
int devfreq_event_get_edev_count(struct device *dev, const char *phandle_name)
{ … }
EXPORT_SYMBOL_GPL(…);

static void devfreq_event_release_edev(struct device *dev)
{ … }

/**
 * devfreq_event_add_edev() - Add new devfreq-event device.
 * @dev		: the device owning the devfreq-event device being created
 * @desc	: the devfreq-event device's descriptor which include essential
 *		  data for devfreq-event device.
 *
 * Note that this function add new devfreq-event device to devfreq-event class
 * list and register the device of the devfreq-event device.
 */
struct devfreq_event_dev *devfreq_event_add_edev(struct device *dev,
						struct devfreq_event_desc *desc)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * devfreq_event_remove_edev() - Remove the devfreq-event device registered.
 * @edev	: the devfreq-event device
 *
 * Note that this function removes the registered devfreq-event device.
 */
int devfreq_event_remove_edev(struct devfreq_event_dev *edev)
{ … }
EXPORT_SYMBOL_GPL(…);

static int devm_devfreq_event_match(struct device *dev, void *res, void *data)
{ … }

static void devm_devfreq_event_release(struct device *dev, void *res)
{ … }

/**
 * devm_devfreq_event_add_edev() - Resource-managed devfreq_event_add_edev()
 * @dev		: the device owning the devfreq-event device being created
 * @desc	: the devfreq-event device's descriptor which include essential
 *		  data for devfreq-event device.
 *
 * Note that this function manages automatically the memory of devfreq-event
 * device using device resource management and simplify the free operation
 * for memory of devfreq-event device.
 */
struct devfreq_event_dev *devm_devfreq_event_add_edev(struct device *dev,
						struct devfreq_event_desc *desc)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * devm_devfreq_event_remove_edev()- Resource-managed devfreq_event_remove_edev()
 * @dev		: the device owning the devfreq-event device being created
 * @edev	: the devfreq-event device
 *
 * Note that this function manages automatically the memory of devfreq-event
 * device using device resource management.
 */
void devm_devfreq_event_remove_edev(struct device *dev,
				struct devfreq_event_dev *edev)
{ … }
EXPORT_SYMBOL_GPL(…);

/*
 * Device attributes for devfreq-event class.
 */
static ssize_t name_show(struct device *dev, struct device_attribute *attr,
			 char *buf)
{ … }
static DEVICE_ATTR_RO(name);

static ssize_t enable_count_show(struct device *dev,
				  struct device_attribute *attr, char *buf)
{ … }
static DEVICE_ATTR_RO(enable_count);

static struct attribute *devfreq_event_attrs[] = …;
ATTRIBUTE_GROUPS(…);

static int __init devfreq_event_init(void)
{ … }
subsys_initcall(devfreq_event_init);
linux/drivers/devfreq/devfreq-event.c
