[deliverable/linux.git] / include / linux / devfreq.h

/*
 * devfreq: Generic Dynamic Voltage and Frequency Scaling (DVFS) Framework
 *	    for Non-CPU Devices.
 *
 * Copyright (C) 2011 Samsung Electronics
 *	MyungJoo Ham <myungjoo.ham@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_H__
#define __LINUX_DEVFREQ_H__

#include <linux/device.h>
#include <linux/notifier.h>
#include <linux/pm_opp.h>

#define DEVFREQ_NAME_LEN 16

/* DEVFREQ notifier interface */
#define DEVFREQ_TRANSITION_NOTIFIER	(0)

/* Transition notifiers of DEVFREQ_TRANSITION_NOTIFIER */
#define	DEVFREQ_PRECHANGE		(0)
#define DEVFREQ_POSTCHANGE		(1)

struct devfreq;

/**
 * struct devfreq_dev_status - Data given from devfreq user device to
 *			     governors. Represents the performance
 *			     statistics.
 * @total_time:		The total time represented by this instance of
 *			devfreq_dev_status
 * @busy_time:		The time that the device was working among the
 *			total_time.
 * @current_frequency:	The operating frequency.
 * @private_data:	An entry not specified by the devfreq framework.
 *			A device and a specific governor may have their
 *			own protocol with private_data. However, because
 *			this is governor-specific, a governor using this
 *			will be only compatible with devices aware of it.
 */
struct devfreq_dev_status {
	/* both since the last measure */
	unsigned long total_time;
	unsigned long busy_time;
	unsigned long current_frequency;
	void *private_data;
};

/*
 * The resulting frequency should be at most this. (this bound is the
 * least upper bound; thus, the resulting freq should be lower or same)
 * If the flag is not set, the resulting frequency should be at most the
 * bound (greatest lower bound)
 */
#define DEVFREQ_FLAG_LEAST_UPPER_BOUND		0x1

/**
 * struct devfreq_dev_profile - Devfreq's user device profile
 * @initial_freq:	The operating frequency when devfreq_add_device() is
 *			called.
 * @polling_ms:		The polling interval in ms. 0 disables polling.
 * @target:		The device should set its operating frequency at
 *			freq or lowest-upper-than-freq value. If freq is
 *			higher than any operable frequency, set maximum.
 *			Before returning, target function should set
 *			freq at the current frequency.
 *			The "flags" parameter's possible values are
 *			explained above with "DEVFREQ_FLAG_*" macros.
 * @get_dev_status:	The device should provide the current performance
 *			status to devfreq. Governors are recommended not to
 *			use this directly. Instead, governors are recommended
 *			to use devfreq_update_stats() along with
 *			devfreq.last_status.
 * @get_cur_freq:	The device should provide the current frequency
 *			at which it is operating.
 * @exit:		An optional callback that is called when devfreq
 *			is removing the devfreq object due to error or
 *			from devfreq_remove_device() call. If the user
 *			has registered devfreq->nb at a notifier-head,
 *			this is the time to unregister it.
 * @freq_table:	Optional list of frequencies to support statistics.
 * @max_state:	The size of freq_table.
 */
struct devfreq_dev_profile {
	unsigned long initial_freq;
	unsigned int polling_ms;

	int (*target)(struct device *dev, unsigned long *freq, u32 flags);
	int (*get_dev_status)(struct device *dev,
			      struct devfreq_dev_status *stat);
	int (*get_cur_freq)(struct device *dev, unsigned long *freq);
	void (*exit)(struct device *dev);

	unsigned long *freq_table;
	unsigned int max_state;
};

/**
 * struct devfreq_governor - Devfreq policy governor
 * @node:		list node - contains registered devfreq governors
 * @name:		Governor's name
 * @get_target_freq:	Returns desired operating frequency for the device.
 *			Basically, get_target_freq will run
 *			devfreq_dev_profile.get_dev_status() to get the
 *			status of the device (load = busy_time / total_time).
 *			If no_central_polling is set, this callback is called
 *			only with update_devfreq() notified by OPP.
 * @event_handler:      Callback for devfreq core framework to notify events
 *                      to governors. Events include per device governor
 *                      init and exit, opp changes out of devfreq, suspend
 *                      and resume of per device devfreq during device idle.
 *
 * Note that the callbacks are called with devfreq->lock locked by devfreq.
 */
struct devfreq_governor {
	struct list_head node;

	const char name[DEVFREQ_NAME_LEN];
	int (*get_target_freq)(struct devfreq *this, unsigned long *freq);
	int (*event_handler)(struct devfreq *devfreq,
				unsigned int event, void *data);
};

/**
 * struct devfreq - Device devfreq structure
 * @node:	list node - contains the devices with devfreq that have been
 *		registered.
 * @lock:	a mutex to protect accessing devfreq.
 * @dev:	device registered by devfreq class. dev.parent is the device
 *		using devfreq.
 * @profile:	device-specific devfreq profile
 * @governor:	method how to choose frequency based on the usage.
 * @governor_name:	devfreq governor name for use with this devfreq
 * @nb:		notifier block used to notify devfreq object that it should
 *		reevaluate operable frequencies. Devfreq users may use
 *		devfreq.nb to the corresponding register notifier call chain.
 * @work:	delayed work for load monitoring.
 * @previous_freq:	previously configured frequency value.
 * @data:	Private data of the governor. The devfreq framework does not
 *		touch this.
 * @min_freq:	Limit minimum frequency requested by user (0: none)
 * @max_freq:	Limit maximum frequency requested by user (0: none)
 * @stop_polling:	 devfreq polling status of a device.
 * @total_trans:	Number of devfreq transitions
 * @trans_table:	Statistics of devfreq transitions
 * @time_in_state:	Statistics of devfreq states
 * @last_stat_updated:	The last time stat updated
 * @transition_notifier_list: list head of DEVFREQ_TRANSITION_NOTIFIER notifier
 *
 * This structure stores the devfreq information for a give device.
 *
 * Note that when a governor accesses entries in struct devfreq in its
 * functions except for the context of callbacks defined in struct
 * devfreq_governor, the governor should protect its access with the
 * struct mutex lock in struct devfreq. A governor may use this mutex
 * to protect its own private data in void *data as well.
 */
struct devfreq {
	struct list_head node;

	struct mutex lock;
	struct device dev;
	struct devfreq_dev_profile *profile;
	const struct devfreq_governor *governor;
	char governor_name[DEVFREQ_NAME_LEN];
	struct notifier_block nb;
	struct delayed_work work;

	unsigned long previous_freq;
	struct devfreq_dev_status last_status;

	void *data; /* private data for governors */

	unsigned long min_freq;
	unsigned long max_freq;
	bool stop_polling;

	/* information for device frequency transition */
	unsigned int total_trans;
	unsigned int *trans_table;
	unsigned long *time_in_state;
	unsigned long last_stat_updated;

	struct srcu_notifier_head transition_notifier_list;
};

struct devfreq_freqs {
	unsigned long old;
	unsigned long new;
};

#if defined(CONFIG_PM_DEVFREQ)
extern struct devfreq *devfreq_add_device(struct device *dev,
				  struct devfreq_dev_profile *profile,
				  const char *governor_name,
				  void *data);
extern int devfreq_remove_device(struct devfreq *devfreq);
extern struct devfreq *devm_devfreq_add_device(struct device *dev,
				  struct devfreq_dev_profile *profile,
				  const char *governor_name,
				  void *data);
extern void devm_devfreq_remove_device(struct device *dev,
				  struct devfreq *devfreq);

/* Supposed to be called by PM callbacks */
extern int devfreq_suspend_device(struct devfreq *devfreq);
extern int devfreq_resume_device(struct devfreq *devfreq);

/* Helper functions for devfreq user device driver with OPP. */
extern struct dev_pm_opp *devfreq_recommended_opp(struct device *dev,
					   unsigned long *freq, u32 flags);
extern int devfreq_register_opp_notifier(struct device *dev,
					 struct devfreq *devfreq);
extern int devfreq_unregister_opp_notifier(struct device *dev,
					   struct devfreq *devfreq);
extern int devm_devfreq_register_opp_notifier(struct device *dev,
					      struct devfreq *devfreq);
extern void devm_devfreq_unregister_opp_notifier(struct device *dev,
						struct devfreq *devfreq);
extern int devfreq_register_notifier(struct devfreq *devfreq,
					struct notifier_block *nb,
					unsigned int list);
extern int devfreq_unregister_notifier(struct devfreq *devfreq,
					struct notifier_block *nb,
					unsigned int list);
extern int devm_devfreq_register_notifier(struct device *dev,
				struct devfreq *devfreq,
				struct notifier_block *nb,
				unsigned int list);
extern void devm_devfreq_unregister_notifier(struct device *dev,
				struct devfreq *devfreq,
				struct notifier_block *nb,
				unsigned int list);
extern struct devfreq *devfreq_get_devfreq_by_phandle(struct device *dev,
						int index);

/**
 * devfreq_update_stats() - update the last_status pointer in struct devfreq
 * @df:		the devfreq instance whose status needs updating
 *
 *  Governors are recommended to use this function along with last_status,
 * which allows other entities to reuse the last_status without affecting
 * the values fetched later by governors.
 */
static inline int devfreq_update_stats(struct devfreq *df)
{
	return df->profile->get_dev_status(df->dev.parent, &df->last_status);
}

#if IS_ENABLED(CONFIG_DEVFREQ_GOV_SIMPLE_ONDEMAND)
/**
 * struct devfreq_simple_ondemand_data - void *data fed to struct devfreq
 *	and devfreq_add_device
 * @upthreshold:	If the load is over this value, the frequency jumps.
 *			Specify 0 to use the default. Valid value = 0 to 100.
 * @downdifferential:	If the load is under upthreshold - downdifferential,
 *			the governor may consider slowing the frequency down.
 *			Specify 0 to use the default. Valid value = 0 to 100.
 *			downdifferential < upthreshold must hold.
 *
 * If the fed devfreq_simple_ondemand_data pointer is NULL to the governor,
 * the governor uses the default values.
 */
struct devfreq_simple_ondemand_data {
	unsigned int upthreshold;
	unsigned int downdifferential;
};
#endif

#else /* !CONFIG_PM_DEVFREQ */
static inline struct devfreq *devfreq_add_device(struct device *dev,
					  struct devfreq_dev_profile *profile,
					  const char *governor_name,
					  void *data)
{
	return ERR_PTR(-ENOSYS);
}

static inline int devfreq_remove_device(struct devfreq *devfreq)
{
	return 0;
}

static inline struct devfreq *devm_devfreq_add_device(struct device *dev,
					struct devfreq_dev_profile *profile,
					const char *governor_name,
					void *data)
{
	return ERR_PTR(-ENOSYS);
}

static inline void devm_devfreq_remove_device(struct device *dev,
					struct devfreq *devfreq)
{
}

static inline int devfreq_suspend_device(struct devfreq *devfreq)
{
	return 0;
}

static inline int devfreq_resume_device(struct devfreq *devfreq)
{
	return 0;
}

static inline struct dev_pm_opp *devfreq_recommended_opp(struct device *dev,
					   unsigned long *freq, u32 flags)
{
	return ERR_PTR(-EINVAL);
}

static inline int devfreq_register_opp_notifier(struct device *dev,
					 struct devfreq *devfreq)
{
	return -EINVAL;
}

static inline int devfreq_unregister_opp_notifier(struct device *dev,
					   struct devfreq *devfreq)
{
	return -EINVAL;
}

static inline int devm_devfreq_register_opp_notifier(struct device *dev,
						     struct devfreq *devfreq)
{
	return -EINVAL;
}

static inline void devm_devfreq_unregister_opp_notifier(struct device *dev,
							struct devfreq *devfreq)
{
}

static inline int devfreq_register_notifier(struct devfreq *devfreq,
					struct notifier_block *nb,
					unsigned int list)
{
	return 0;
}

static inline int devfreq_unregister_notifier(struct devfreq *devfreq,
					struct notifier_block *nb,
					unsigned int list)
{
	return 0;
}

static inline int devm_devfreq_register_notifier(struct device *dev,
				struct devfreq *devfreq,
				struct notifier_block *nb,
				unsigned int list)
{
	return 0;
}

static inline void devm_devfreq_unregister_notifier(struct device *dev,
				struct devfreq *devfreq,
				struct notifier_block *nb,
				unsigned int list)
{
}

static inline struct devfreq *devfreq_get_devfreq_by_phandle(struct device *dev,
							int index)
{
	return ERR_PTR(-ENODEV);
}

static inline int devfreq_update_stats(struct devfreq *df)
{
	return -EINVAL;
}
#endif /* CONFIG_PM_DEVFREQ */

#endif /* __LINUX_DEVFREQ_H__ */
Commit	Line	Data
a3c98b8b MH	1	/*
	2	* devfreq: Generic Dynamic Voltage and Frequency Scaling (DVFS) Framework
	3	* for Non-CPU Devices.
	4	*
	5	* Copyright (C) 2011 Samsung Electronics
	6	* MyungJoo Ham <myungjoo.ham@samsung.com>
	7	*
	8	* This program is free software; you can redistribute it and/or modify
	9	* it under the terms of the GNU General Public License version 2 as
	10	* published by the Free Software Foundation.
	11	*/
	12
	13	#ifndef __LINUX_DEVFREQ_H__
	14	#define __LINUX_DEVFREQ_H__
	15
	16	#include <linux/device.h>
	17	#include <linux/notifier.h>
e4db1c74	18	#include <linux/pm_opp.h>
a3c98b8b MH	19
	20	#define DEVFREQ_NAME_LEN 16
	21
0fe3a664 CC	22	/* DEVFREQ notifier interface */
	23	#define DEVFREQ_TRANSITION_NOTIFIER (0)
	24
	25	/* Transition notifiers of DEVFREQ_TRANSITION_NOTIFIER */
	26	#define DEVFREQ_PRECHANGE (0)
	27	#define DEVFREQ_POSTCHANGE (1)
	28
a3c98b8b MH	29	struct devfreq;
	30
	31	/**
	32	* struct devfreq_dev_status - Data given from devfreq user device to
	33	* governors. Represents the performance
	34	* statistics.
e09651fc	35	* @total_time: The total time represented by this instance of
a3c98b8b	36	* devfreq_dev_status
e09651fc	37	* @busy_time: The time that the device was working among the
a3c98b8b	38	* total_time.
e09651fc NM	39	* @current_frequency: The operating frequency.
e09651fc NM	40	* @private_data: An entry not specified by the devfreq framework.
a3c98b8b MH	41	* A device and a specific governor may have their
	42	* own protocol with private_data. However, because
	43	* this is governor-specific, a governor using this
	44	* will be only compatible with devices aware of it.
	45	*/
	46	struct devfreq_dev_status {
	47	/* both since the last measure */
	48	unsigned long total_time;
	49	unsigned long busy_time;
	50	unsigned long current_frequency;
1a51cfdc	51	void *private_data;
a3c98b8b MH	52	};
a3c98b8b MH	53
ab5f299f MH	54	/*
	55	* The resulting frequency should be at most this. (this bound is the
	56	* least upper bound; thus, the resulting freq should be lower or same)
	57	* If the flag is not set, the resulting frequency should be at most the
	58	* bound (greatest lower bound)
	59	*/
	60	#define DEVFREQ_FLAG_LEAST_UPPER_BOUND 0x1
	61
a3c98b8b MH	62	/**
a3c98b8b MH	63	* struct devfreq_dev_profile - Devfreq's user device profile
e09651fc	64	* @initial_freq: The operating frequency when devfreq_add_device() is
a3c98b8b	65	* called.
e09651fc NM	66	* @polling_ms: The polling interval in ms. 0 disables polling.
e09651fc NM	67	* @target: The device should set its operating frequency at
a3c98b8b MH	68	* freq or lowest-upper-than-freq value. If freq is
	69	* higher than any operable frequency, set maximum.
	70	* Before returning, target function should set
	71	* freq at the current frequency.
ab5f299f MH	72	* The "flags" parameter's possible values are
ab5f299f MH	73	* explained above with "DEVFREQ_FLAG_*" macros.
e09651fc	74	* @get_dev_status: The device should provide the current performance
d54cdf3f MH	75	* status to devfreq. Governors are recommended not to
	76	* use this directly. Instead, governors are recommended
	77	* to use devfreq_update_stats() along with
	78	* devfreq.last_status.
e09651fc	79	* @get_cur_freq: The device should provide the current frequency
7f98a905	80	* at which it is operating.
e09651fc	81	* @exit: An optional callback that is called when devfreq
a3c98b8b MH	82	* is removing the devfreq object due to error or
	83	* from devfreq_remove_device() call. If the user
	84	* has registered devfreq->nb at a notifier-head,
	85	* this is the time to unregister it.
e552bbaf JL	86	* @freq_table: Optional list of frequencies to support statistics.
e552bbaf JL	87	* @max_state: The size of freq_table.
a3c98b8b MH	88	*/
	89	struct devfreq_dev_profile {
	90	unsigned long initial_freq;
	91	unsigned int polling_ms;
	92
ab5f299f	93	int (target)(struct device dev, unsigned long *freq, u32 flags);
a3c98b8b MH	94	int (get_dev_status)(struct device dev,
a3c98b8b MH	95	struct devfreq_dev_status *stat);
7f98a905	96	int (get_cur_freq)(struct device dev, unsigned long *freq);
a3c98b8b	97	void (exit)(struct device dev);
e552bbaf	98
0ec09ac2	99	unsigned long *freq_table;
e552bbaf	100	unsigned int max_state;
a3c98b8b MH	101	};
	102
	103	/**
	104	* struct devfreq_governor - Devfreq policy governor
3aa173b8	105	* @node: list node - contains registered devfreq governors
e09651fc NM	106	* @name: Governor's name
e09651fc NM	107	* @get_target_freq: Returns desired operating frequency for the device.
a3c98b8b MH	108	* Basically, get_target_freq will run
	109	* devfreq_dev_profile.get_dev_status() to get the
	110	* status of the device (load = busy_time / total_time).
	111	* If no_central_polling is set, this callback is called
	112	* only with update_devfreq() notified by OPP.
e09651fc	113	* @event_handler: Callback for devfreq core framework to notify events
7e6fdd4b RV	114	* to governors. Events include per device governor
	115	* init and exit, opp changes out of devfreq, suspend
	116	* and resume of per device devfreq during device idle.
a3c98b8b MH	117	*
	118	* Note that the callbacks are called with devfreq->lock locked by devfreq.
	119	*/
	120	struct devfreq_governor {
3aa173b8 NM	121	struct list_head node;
3aa173b8 NM	122
a3c98b8b MH	123	const char name[DEVFREQ_NAME_LEN];
a3c98b8b MH	124	int (get_target_freq)(struct devfreq this, unsigned long *freq);
7e6fdd4b RV	125	int (event_handler)(struct devfreq devfreq,
7e6fdd4b RV	126	unsigned int event, void *data);
a3c98b8b MH	127	};
	128
	129	/**
	130	* struct devfreq - Device devfreq structure
e09651fc	131	* @node: list node - contains the devices with devfreq that have been
a3c98b8b	132	* registered.
e09651fc NM	133	* @lock: a mutex to protect accessing devfreq.
e09651fc NM	134	* @dev: device registered by devfreq class. dev.parent is the device
a3c98b8b	135	* using devfreq.
e09651fc NM	136	* @profile: device-specific devfreq profile
e09651fc NM	137	* @governor: method how to choose frequency based on the usage.
1b5c1be2	138	* @governor_name: devfreq governor name for use with this devfreq
e09651fc	139	* @nb: notifier block used to notify devfreq object that it should
a3c98b8b MH	140	* reevaluate operable frequencies. Devfreq users may use
a3c98b8b MH	141	* devfreq.nb to the corresponding register notifier call chain.
e09651fc NM	142	* @work: delayed work for load monitoring.
	143	* @previous_freq: previously configured frequency value.
	144	* @data: Private data of the governor. The devfreq framework does not
a3c98b8b	145	* touch this.
e09651fc NM	146	* @min_freq: Limit minimum frequency requested by user (0: none)
	147	* @max_freq: Limit maximum frequency requested by user (0: none)
	148	* @stop_polling: devfreq polling status of a device.
e552bbaf JL	149	* @total_trans: Number of devfreq transitions
	150	* @trans_table: Statistics of devfreq transitions
	151	* @time_in_state: Statistics of devfreq states
	152	* @last_stat_updated: The last time stat updated
0fe3a664	153	* @transition_notifier_list: list head of DEVFREQ_TRANSITION_NOTIFIER notifier
a3c98b8b MH	154	*
	155	* This structure stores the devfreq information for a give device.
	156	*
	157	* Note that when a governor accesses entries in struct devfreq in its
	158	* functions except for the context of callbacks defined in struct
	159	* devfreq_governor, the governor should protect its access with the
	160	* struct mutex lock in struct devfreq. A governor may use this mutex
	161	* to protect its own private data in void *data as well.
	162	*/
	163	struct devfreq {
	164	struct list_head node;
	165
	166	struct mutex lock;
	167	struct device dev;
	168	struct devfreq_dev_profile *profile;
	169	const struct devfreq_governor *governor;
1b5c1be2	170	char governor_name[DEVFREQ_NAME_LEN];
a3c98b8b	171	struct notifier_block nb;
7e6fdd4b	172	struct delayed_work work;
a3c98b8b	173
a3c98b8b	174	unsigned long previous_freq;
08e75e75	175	struct devfreq_dev_status last_status;
a3c98b8b MH	176
	177	void data; / private data for governors */
	178
6530b9de MH	179	unsigned long min_freq;
6530b9de MH	180	unsigned long max_freq;
7e6fdd4b	181	bool stop_polling;
e552bbaf	182
0585123e	183	/* information for device frequency transition */
e552bbaf JL	184	unsigned int total_trans;
	185	unsigned int *trans_table;
	186	unsigned long *time_in_state;
	187	unsigned long last_stat_updated;
0fe3a664 CC	188
	189	struct srcu_notifier_head transition_notifier_list;
	190	};
	191
	192	struct devfreq_freqs {
	193	unsigned long old;
	194	unsigned long new;
a3c98b8b MH	195	};
	196
	197	#if defined(CONFIG_PM_DEVFREQ)
	198	extern struct devfreq devfreq_add_device(struct device dev,
	199	struct devfreq_dev_profile *profile,
1b5c1be2	200	const char *governor_name,
a3c98b8b MH	201	void *data);
a3c98b8b MH	202	extern int devfreq_remove_device(struct devfreq *devfreq);
8cd84092 CC	203	extern struct devfreq devm_devfreq_add_device(struct device dev,
	204	struct devfreq_dev_profile *profile,
	205	const char *governor_name,
	206	void *data);
	207	extern void devm_devfreq_remove_device(struct device *dev,
	208	struct devfreq *devfreq);
de9c7394	209
464ed18e	210	/* Supposed to be called by PM callbacks */
206c30cf RV	211	extern int devfreq_suspend_device(struct devfreq *devfreq);
206c30cf RV	212	extern int devfreq_resume_device(struct devfreq *devfreq);
a3c98b8b MH	213
a3c98b8b MH	214	/* Helper functions for devfreq user device driver with OPP. */
47d43ba7	215	extern struct dev_pm_opp devfreq_recommended_opp(struct device dev,
ab5f299f	216	unsigned long *freq, u32 flags);
a3c98b8b MH	217	extern int devfreq_register_opp_notifier(struct device *dev,
	218	struct devfreq *devfreq);
	219	extern int devfreq_unregister_opp_notifier(struct device *dev,
	220	struct devfreq *devfreq);
d5b040d0 CC	221	extern int devm_devfreq_register_opp_notifier(struct device *dev,
	222	struct devfreq *devfreq);
	223	extern void devm_devfreq_unregister_opp_notifier(struct device *dev,
	224	struct devfreq *devfreq);
0fe3a664 CC	225	extern int devfreq_register_notifier(struct devfreq *devfreq,
	226	struct notifier_block *nb,
	227	unsigned int list);
	228	extern int devfreq_unregister_notifier(struct devfreq *devfreq,
	229	struct notifier_block *nb,
	230	unsigned int list);
	231	extern int devm_devfreq_register_notifier(struct device *dev,
	232	struct devfreq *devfreq,
	233	struct notifier_block *nb,
	234	unsigned int list);
	235	extern void devm_devfreq_unregister_notifier(struct device *dev,
	236	struct devfreq *devfreq,
	237	struct notifier_block *nb,
	238	unsigned int list);
8f510aeb CC	239	extern struct devfreq devfreq_get_devfreq_by_phandle(struct device dev,
	240	int index);
	241
08e75e75 JM	242	/**
	243	* devfreq_update_stats() - update the last_status pointer in struct devfreq
	244	* @df: the devfreq instance whose status needs updating
d54cdf3f MH	245	*
	246	* Governors are recommended to use this function along with last_status,
	247	* which allows other entities to reuse the last_status without affecting
	248	* the values fetched later by governors.
08e75e75 JM	249	*/
	250	static inline int devfreq_update_stats(struct devfreq *df)
	251	{
	252	return df->profile->get_dev_status(df->dev.parent, &df->last_status);
	253	}
	254
883d588e	255	#if IS_ENABLED(CONFIG_DEVFREQ_GOV_SIMPLE_ONDEMAND)
ce26c5bb MH	256	/**
	257	* struct devfreq_simple_ondemand_data - void *data fed to struct devfreq
	258	* and devfreq_add_device
e09651fc	259	* @upthreshold: If the load is over this value, the frequency jumps.
ce26c5bb	260	* Specify 0 to use the default. Valid value = 0 to 100.
e09651fc	261	* @downdifferential: If the load is under upthreshold - downdifferential,
ce26c5bb MH	262	* the governor may consider slowing the frequency down.
	263	* Specify 0 to use the default. Valid value = 0 to 100.
	264	* downdifferential < upthreshold must hold.
	265	*
	266	* If the fed devfreq_simple_ondemand_data pointer is NULL to the governor,
	267	* the governor uses the default values.
	268	*/
	269	struct devfreq_simple_ondemand_data {
	270	unsigned int upthreshold;
	271	unsigned int downdifferential;
	272	};
	273	#endif
	274
a3c98b8b	275	#else /* !CONFIG_PM_DEVFREQ */
5faaa035	276	static inline struct devfreq devfreq_add_device(struct device dev,
a3c98b8b	277	struct devfreq_dev_profile *profile,
1b5c1be2	278	const char *governor_name,
a95e1f5d	279	void *data)
a3c98b8b	280	{
8cd84092	281	return ERR_PTR(-ENOSYS);
a3c98b8b MH	282	}
a3c98b8b MH	283
5faaa035	284	static inline int devfreq_remove_device(struct devfreq *devfreq)
a3c98b8b MH	285	{
	286	return 0;
	287	}
	288
8cd84092 CC	289	static inline struct devfreq devm_devfreq_add_device(struct device dev,
	290	struct devfreq_dev_profile *profile,
	291	const char *governor_name,
	292	void *data)
	293	{
	294	return ERR_PTR(-ENOSYS);
	295	}
	296
	297	static inline void devm_devfreq_remove_device(struct device *dev,
	298	struct devfreq *devfreq)
	299	{
	300	}
	301
5faaa035	302	static inline int devfreq_suspend_device(struct devfreq *devfreq)
206c30cf RV	303	{
	304	return 0;
	305	}
	306
5faaa035	307	static inline int devfreq_resume_device(struct devfreq *devfreq)
206c30cf RV	308	{
	309	return 0;
	310	}
	311
47d43ba7	312	static inline struct dev_pm_opp devfreq_recommended_opp(struct device dev,
ab5f299f	313	unsigned long *freq, u32 flags)
a3c98b8b	314	{
5faaa035	315	return ERR_PTR(-EINVAL);
a3c98b8b MH	316	}
a3c98b8b MH	317
5faaa035	318	static inline int devfreq_register_opp_notifier(struct device *dev,
a3c98b8b MH	319	struct devfreq *devfreq)
	320	{
	321	return -EINVAL;
	322	}
	323
5faaa035	324	static inline int devfreq_unregister_opp_notifier(struct device *dev,
a3c98b8b MH	325	struct devfreq *devfreq)
	326	{
	327	return -EINVAL;
	328	}
	329
d5b040d0 CC	330	static inline int devm_devfreq_register_opp_notifier(struct device *dev,
	331	struct devfreq *devfreq)
	332	{
	333	return -EINVAL;
	334	}
	335
	336	static inline void devm_devfreq_unregister_opp_notifier(struct device *dev,
	337	struct devfreq *devfreq)
	338	{
	339	}
08e75e75	340
0fe3a664 CC	341	static inline int devfreq_register_notifier(struct devfreq *devfreq,
	342	struct notifier_block *nb,
	343	unsigned int list)
	344	{
	345	return 0;
	346	}
	347
	348	static inline int devfreq_unregister_notifier(struct devfreq *devfreq,
	349	struct notifier_block *nb,
	350	unsigned int list)
	351	{
	352	return 0;
	353	}
	354
	355	static inline int devm_devfreq_register_notifier(struct device *dev,
	356	struct devfreq *devfreq,
	357	struct notifier_block *nb,
	358	unsigned int list)
	359	{
	360	return 0;
	361	}
	362
	363	static inline void devm_devfreq_unregister_notifier(struct device *dev,
	364	struct devfreq *devfreq,
	365	struct notifier_block *nb,
	366	unsigned int list)
	367	{
	368	}
	369
8f510aeb CC	370	static inline struct devfreq devfreq_get_devfreq_by_phandle(struct device dev,
	371	int index)
	372	{
	373	return ERR_PTR(-ENODEV);
	374	}
	375
08e75e75 JM	376	static inline int devfreq_update_stats(struct devfreq *df)
	377	{
	378	return -EINVAL;
	379	}
a3c98b8b MH	380	#endif /* CONFIG_PM_DEVFREQ */
	381
	382	#endif /* __LINUX_DEVFREQ_H__ */