[thirdparty/kernel/stable.git] / include / linux / devfreq.h

/* SPDX-License-Identifier: GPL-2.0-only */
/*
 * devfreq: Generic Dynamic Voltage and Frequency Scaling (DVFS) Framework
 *	    for Non-CPU Devices.
 *
 * Copyright (C) 2011 Samsung Electronics
 *	MyungJoo Ham <myungjoo.ham@samsung.com>
 */

#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 governor name */
#define DEVFREQ_GOV_SIMPLE_ONDEMAND	"simple_ondemand"
#define DEVFREQ_GOV_PERFORMANCE		"performance"
#define DEVFREQ_GOV_POWERSAVE		"powersave"
#define DEVFREQ_GOV_USERSPACE		"userspace"
#define DEVFREQ_GOV_PASSIVE		"passive"

/* 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_governor;

/**
 * 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
 *			and freq_table must be generated in ascending order.
 * @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 - 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)
 * @scaling_min_freq:	Limit minimum frequency requested by OPP interface
 * @scaling_max_freq:	Limit maximum frequency requested by OPP interface
 * @stop_polling:	 devfreq polling status of a device.
 * @suspend_freq:	 frequency of a device set during suspend phase.
 * @resume_freq:	 frequency of a device set in resume phase.
 * @suspend_count:	 suspend requests counter for 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;
	unsigned long scaling_min_freq;
	unsigned long scaling_max_freq;
	bool stop_polling;

	unsigned long suspend_freq;
	unsigned long resume_freq;
	atomic_t suspend_count;

	/* 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);

extern void devfreq_suspend(void);
extern void devfreq_resume(void);

/**
 * update_devfreq() - Reevaluate the device and configure frequency
 * @devfreq:	the devfreq device
 *
 * Note: devfreq->lock must be held
 */
extern int update_devfreq(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);

#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

#if IS_ENABLED(CONFIG_DEVFREQ_GOV_PASSIVE)
/**
 * struct devfreq_passive_data - void *data fed to struct devfreq
 *	and devfreq_add_device
 * @parent:	the devfreq instance of parent device.
 * @get_target_freq:	Optional callback, Returns desired operating frequency
 *			for the device using passive governor. That is called
 *			when passive governor should decide the next frequency
 *			by using the new frequency of parent devfreq device
 *			using governors except for passive governor.
 *			If the devfreq device has the specific method to decide
 *			the next frequency, should use this callback.
 * @this:	the devfreq instance of own device.
 * @nb:		the notifier block for DEVFREQ_TRANSITION_NOTIFIER list
 *
 * The devfreq_passive_data have to set the devfreq instance of parent
 * device with governors except for the passive governor. But, don't need to
 * initialize the 'this' and 'nb' field because the devfreq core will handle
 * them.
 */
struct devfreq_passive_data {
	/* Should set the devfreq instance of parent device */
	struct devfreq *parent;

	/* Optional callback to decide the next frequency of passvice device */
	int (*get_target_freq)(struct devfreq *this, unsigned long *freq);

	/* For passive governor's internal use. Don't need to set them */
	struct devfreq *this;
	struct notifier_block nb;
};
#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 void devfreq_suspend(void) {}
static inline void devfreq_resume(void) {}

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
d2912cb1	1	/* SPDX-License-Identifier: GPL-2.0-only */
a3c98b8b MH	2	/*
	3	* devfreq: Generic Dynamic Voltage and Frequency Scaling (DVFS) Framework
	4	* for Non-CPU Devices.
	5	*
	6	* Copyright (C) 2011 Samsung Electronics
	7	* MyungJoo Ham <myungjoo.ham@samsung.com>
a3c98b8b MH	8	*/
	9
	10	#ifndef __LINUX_DEVFREQ_H__
	11	#define __LINUX_DEVFREQ_H__
	12
	13	#include <linux/device.h>
	14	#include <linux/notifier.h>
e4db1c74	15	#include <linux/pm_opp.h>
a3c98b8b MH	16
	17	#define DEVFREQ_NAME_LEN 16
	18
aa7c352f CC	19	/* DEVFREQ governor name */
	20	#define DEVFREQ_GOV_SIMPLE_ONDEMAND "simple_ondemand"
	21	#define DEVFREQ_GOV_PERFORMANCE "performance"
	22	#define DEVFREQ_GOV_POWERSAVE "powersave"
	23	#define DEVFREQ_GOV_USERSPACE "userspace"
	24	#define DEVFREQ_GOV_PASSIVE "passive"
	25
0fe3a664 CC	26	/* DEVFREQ notifier interface */
	27	#define DEVFREQ_TRANSITION_NOTIFIER (0)
	28
	29	/* Transition notifiers of DEVFREQ_TRANSITION_NOTIFIER */
	30	#define DEVFREQ_PRECHANGE (0)
	31	#define DEVFREQ_POSTCHANGE (1)
	32
a3c98b8b	33	struct devfreq;
3ea6b700	34	struct devfreq_governor;
a3c98b8b MH	35
	36	/**
	37	* struct devfreq_dev_status - Data given from devfreq user device to
	38	* governors. Represents the performance
	39	* statistics.
e09651fc	40	* @total_time: The total time represented by this instance of
a3c98b8b	41	* devfreq_dev_status
e09651fc	42	* @busy_time: The time that the device was working among the
a3c98b8b	43	* total_time.
e09651fc NM	44	* @current_frequency: The operating frequency.
e09651fc NM	45	* @private_data: An entry not specified by the devfreq framework.
a3c98b8b MH	46	* A device and a specific governor may have their
	47	* own protocol with private_data. However, because
	48	* this is governor-specific, a governor using this
	49	* will be only compatible with devices aware of it.
	50	*/
	51	struct devfreq_dev_status {
	52	/* both since the last measure */
	53	unsigned long total_time;
	54	unsigned long busy_time;
	55	unsigned long current_frequency;
1a51cfdc	56	void *private_data;
a3c98b8b MH	57	};
a3c98b8b MH	58
ab5f299f MH	59	/*
	60	* The resulting frequency should be at most this. (this bound is the
	61	* least upper bound; thus, the resulting freq should be lower or same)
	62	* If the flag is not set, the resulting frequency should be at most the
	63	* bound (greatest lower bound)
	64	*/
	65	#define DEVFREQ_FLAG_LEAST_UPPER_BOUND 0x1
	66
a3c98b8b MH	67	/**
a3c98b8b MH	68	* struct devfreq_dev_profile - Devfreq's user device profile
e09651fc	69	* @initial_freq: The operating frequency when devfreq_add_device() is
a3c98b8b	70	* called.
e09651fc NM	71	* @polling_ms: The polling interval in ms. 0 disables polling.
e09651fc NM	72	* @target: The device should set its operating frequency at
a3c98b8b MH	73	* freq or lowest-upper-than-freq value. If freq is
	74	* higher than any operable frequency, set maximum.
	75	* Before returning, target function should set
	76	* freq at the current frequency.
ab5f299f MH	77	* The "flags" parameter's possible values are
ab5f299f MH	78	* explained above with "DEVFREQ_FLAG_*" macros.
e09651fc	79	* @get_dev_status: The device should provide the current performance
d54cdf3f MH	80	* status to devfreq. Governors are recommended not to
	81	* use this directly. Instead, governors are recommended
	82	* to use devfreq_update_stats() along with
	83	* devfreq.last_status.
e09651fc	84	* @get_cur_freq: The device should provide the current frequency
7f98a905	85	* at which it is operating.
e09651fc	86	* @exit: An optional callback that is called when devfreq
a3c98b8b MH	87	* is removing the devfreq object due to error or
	88	* from devfreq_remove_device() call. If the user
	89	* has registered devfreq->nb at a notifier-head,
	90	* this is the time to unregister it.
416b46a2 CC	91	* @freq_table: Optional list of frequencies to support statistics
	92	* and freq_table must be generated in ascending order.
	93	* @max_state: The size of freq_table.
a3c98b8b MH	94	*/
	95	struct devfreq_dev_profile {
	96	unsigned long initial_freq;
	97	unsigned int polling_ms;
	98
ab5f299f	99	int (target)(struct device dev, unsigned long *freq, u32 flags);
a3c98b8b MH	100	int (get_dev_status)(struct device dev,
a3c98b8b MH	101	struct devfreq_dev_status *stat);
7f98a905	102	int (get_cur_freq)(struct device dev, unsigned long *freq);
a3c98b8b	103	void (exit)(struct device dev);
e552bbaf	104
0ec09ac2	105	unsigned long *freq_table;
e552bbaf	106	unsigned int max_state;
a3c98b8b MH	107	};
a3c98b8b MH	108
a3c98b8b MH	109	/**
a3c98b8b MH	110	* struct devfreq - Device devfreq structure
e09651fc	111	* @node: list node - contains the devices with devfreq that have been
a3c98b8b	112	* registered.
e09651fc NM	113	* @lock: a mutex to protect accessing devfreq.
e09651fc NM	114	* @dev: device registered by devfreq class. dev.parent is the device
a3c98b8b	115	* using devfreq.
e09651fc NM	116	* @profile: device-specific devfreq profile
e09651fc NM	117	* @governor: method how to choose frequency based on the usage.
1b5c1be2	118	* @governor_name: devfreq governor name for use with this devfreq
e09651fc	119	* @nb: notifier block used to notify devfreq object that it should
a3c98b8b MH	120	* reevaluate operable frequencies. Devfreq users may use
a3c98b8b MH	121	* devfreq.nb to the corresponding register notifier call chain.
e09651fc NM	122	* @work: delayed work for load monitoring.
	123	* @previous_freq: previously configured frequency value.
	124	* @data: Private data of the governor. The devfreq framework does not
a3c98b8b	125	* touch this.
e09651fc NM	126	* @min_freq: Limit minimum frequency requested by user (0: none)
e09651fc NM	127	* @max_freq: Limit maximum frequency requested by user (0: none)
f1d981ea CC	128	* @scaling_min_freq: Limit minimum frequency requested by OPP interface
f1d981ea CC	129	* @scaling_max_freq: Limit maximum frequency requested by OPP interface
e09651fc	130	* @stop_polling: devfreq polling status of a device.
83f8ca45 LL	131	* @suspend_freq: frequency of a device set during suspend phase.
	132	* @resume_freq: frequency of a device set in resume phase.
	133	* @suspend_count: suspend requests counter for a device.
e552bbaf JL	134	* @total_trans: Number of devfreq transitions
	135	* @trans_table: Statistics of devfreq transitions
	136	* @time_in_state: Statistics of devfreq states
	137	* @last_stat_updated: The last time stat updated
0fe3a664	138	* @transition_notifier_list: list head of DEVFREQ_TRANSITION_NOTIFIER notifier
a3c98b8b MH	139	*
	140	* This structure stores the devfreq information for a give device.
	141	*
	142	* Note that when a governor accesses entries in struct devfreq in its
	143	* functions except for the context of callbacks defined in struct
	144	* devfreq_governor, the governor should protect its access with the
	145	* struct mutex lock in struct devfreq. A governor may use this mutex
	146	* to protect its own private data in void *data as well.
	147	*/
	148	struct devfreq {
	149	struct list_head node;
	150
	151	struct mutex lock;
	152	struct device dev;
	153	struct devfreq_dev_profile *profile;
	154	const struct devfreq_governor *governor;
1b5c1be2	155	char governor_name[DEVFREQ_NAME_LEN];
a3c98b8b	156	struct notifier_block nb;
7e6fdd4b	157	struct delayed_work work;
a3c98b8b	158
a3c98b8b	159	unsigned long previous_freq;
08e75e75	160	struct devfreq_dev_status last_status;
a3c98b8b MH	161
	162	void data; / private data for governors */
	163
6530b9de MH	164	unsigned long min_freq;
6530b9de MH	165	unsigned long max_freq;
f1d981ea CC	166	unsigned long scaling_min_freq;
f1d981ea CC	167	unsigned long scaling_max_freq;
7e6fdd4b	168	bool stop_polling;
e552bbaf	169
83f8ca45 LL	170	unsigned long suspend_freq;
	171	unsigned long resume_freq;
	172	atomic_t suspend_count;
	173
0585123e	174	/* information for device frequency transition */
e552bbaf JL	175	unsigned int total_trans;
	176	unsigned int *trans_table;
	177	unsigned long *time_in_state;
	178	unsigned long last_stat_updated;
0fe3a664 CC	179
	180	struct srcu_notifier_head transition_notifier_list;
	181	};
	182
	183	struct devfreq_freqs {
	184	unsigned long old;
	185	unsigned long new;
a3c98b8b MH	186	};
	187
	188	#if defined(CONFIG_PM_DEVFREQ)
	189	extern struct devfreq devfreq_add_device(struct device dev,
	190	struct devfreq_dev_profile *profile,
1b5c1be2	191	const char *governor_name,
a3c98b8b MH	192	void *data);
a3c98b8b MH	193	extern int devfreq_remove_device(struct devfreq *devfreq);
8cd84092 CC	194	extern struct devfreq devm_devfreq_add_device(struct device dev,
	195	struct devfreq_dev_profile *profile,
	196	const char *governor_name,
	197	void *data);
	198	extern void devm_devfreq_remove_device(struct device *dev,
	199	struct devfreq *devfreq);
de9c7394	200
464ed18e	201	/* Supposed to be called by PM callbacks */
206c30cf RV	202	extern int devfreq_suspend_device(struct devfreq *devfreq);
206c30cf RV	203	extern int devfreq_resume_device(struct devfreq *devfreq);
a3c98b8b	204
59031956 LL	205	extern void devfreq_suspend(void);
	206	extern void devfreq_resume(void);
	207
b596d895 MK	208	/**
	209	* update_devfreq() - Reevaluate the device and configure frequency
	210	* @devfreq: the devfreq device
	211	*
	212	* Note: devfreq->lock must be held
	213	*/
	214	extern int update_devfreq(struct devfreq *devfreq);
	215
a3c98b8b	216	/* Helper functions for devfreq user device driver with OPP. */
47d43ba7	217	extern struct dev_pm_opp devfreq_recommended_opp(struct device dev,
ab5f299f	218	unsigned long *freq, u32 flags);
a3c98b8b MH	219	extern int devfreq_register_opp_notifier(struct device *dev,
	220	struct devfreq *devfreq);
	221	extern int devfreq_unregister_opp_notifier(struct device *dev,
	222	struct devfreq *devfreq);
d5b040d0 CC	223	extern int devm_devfreq_register_opp_notifier(struct device *dev,
	224	struct devfreq *devfreq);
	225	extern void devm_devfreq_unregister_opp_notifier(struct device *dev,
	226	struct devfreq *devfreq);
0fe3a664 CC	227	extern int devfreq_register_notifier(struct devfreq *devfreq,
	228	struct notifier_block *nb,
	229	unsigned int list);
	230	extern int devfreq_unregister_notifier(struct devfreq *devfreq,
	231	struct notifier_block *nb,
	232	unsigned int list);
	233	extern int devm_devfreq_register_notifier(struct device *dev,
	234	struct devfreq *devfreq,
	235	struct notifier_block *nb,
	236	unsigned int list);
	237	extern void devm_devfreq_unregister_notifier(struct device *dev,
	238	struct devfreq *devfreq,
	239	struct notifier_block *nb,
	240	unsigned int list);
8f510aeb CC	241	extern struct devfreq devfreq_get_devfreq_by_phandle(struct device dev,
	242	int index);
	243
883d588e	244	#if IS_ENABLED(CONFIG_DEVFREQ_GOV_SIMPLE_ONDEMAND)
ce26c5bb MH	245	/**
	246	* struct devfreq_simple_ondemand_data - void *data fed to struct devfreq
	247	* and devfreq_add_device
e09651fc	248	* @upthreshold: If the load is over this value, the frequency jumps.
ce26c5bb	249	* Specify 0 to use the default. Valid value = 0 to 100.
e09651fc	250	* @downdifferential: If the load is under upthreshold - downdifferential,
ce26c5bb MH	251	* the governor may consider slowing the frequency down.
	252	* Specify 0 to use the default. Valid value = 0 to 100.
	253	* downdifferential < upthreshold must hold.
	254	*
	255	* If the fed devfreq_simple_ondemand_data pointer is NULL to the governor,
	256	* the governor uses the default values.
	257	*/
	258	struct devfreq_simple_ondemand_data {
	259	unsigned int upthreshold;
	260	unsigned int downdifferential;
	261	};
	262	#endif
	263
99613311 CC	264	#if IS_ENABLED(CONFIG_DEVFREQ_GOV_PASSIVE)
	265	/**
	266	* struct devfreq_passive_data - void *data fed to struct devfreq
	267	* and devfreq_add_device
	268	* @parent: the devfreq instance of parent device.
	269	* @get_target_freq: Optional callback, Returns desired operating frequency
	270	* for the device using passive governor. That is called
	271	* when passive governor should decide the next frequency
	272	* by using the new frequency of parent devfreq device
	273	* using governors except for passive governor.
	274	* If the devfreq device has the specific method to decide
	275	* the next frequency, should use this callback.
	276	* @this: the devfreq instance of own device.
	277	* @nb: the notifier block for DEVFREQ_TRANSITION_NOTIFIER list
	278	*
	279	* The devfreq_passive_data have to set the devfreq instance of parent
	280	* device with governors except for the passive governor. But, don't need to
	281	* initialize the 'this' and 'nb' field because the devfreq core will handle
	282	* them.
	283	*/
	284	struct devfreq_passive_data {
	285	/* Should set the devfreq instance of parent device */
	286	struct devfreq *parent;
	287
	288	/* Optional callback to decide the next frequency of passvice device */
	289	int (get_target_freq)(struct devfreq this, unsigned long *freq);
	290
	291	/* For passive governor's internal use. Don't need to set them */
	292	struct devfreq *this;
	293	struct notifier_block nb;
	294	};
	295	#endif
	296
a3c98b8b	297	#else /* !CONFIG_PM_DEVFREQ */
5faaa035	298	static inline struct devfreq devfreq_add_device(struct device dev,
a3c98b8b	299	struct devfreq_dev_profile *profile,
1b5c1be2	300	const char *governor_name,
a95e1f5d	301	void *data)
a3c98b8b	302	{
8cd84092	303	return ERR_PTR(-ENOSYS);
a3c98b8b MH	304	}
a3c98b8b MH	305
5faaa035	306	static inline int devfreq_remove_device(struct devfreq *devfreq)
a3c98b8b MH	307	{
	308	return 0;
	309	}
	310
8cd84092 CC	311	static inline struct devfreq devm_devfreq_add_device(struct device dev,
	312	struct devfreq_dev_profile *profile,
	313	const char *governor_name,
	314	void *data)
	315	{
	316	return ERR_PTR(-ENOSYS);
	317	}
	318
	319	static inline void devm_devfreq_remove_device(struct device *dev,
	320	struct devfreq *devfreq)
	321	{
	322	}
	323
5faaa035	324	static inline int devfreq_suspend_device(struct devfreq *devfreq)
206c30cf RV	325	{
	326	return 0;
	327	}
	328
5faaa035	329	static inline int devfreq_resume_device(struct devfreq *devfreq)
206c30cf RV	330	{
	331	return 0;
	332	}
	333
59031956 LL	334	static inline void devfreq_suspend(void) {}
	335	static inline void devfreq_resume(void) {}
	336
47d43ba7	337	static inline struct dev_pm_opp devfreq_recommended_opp(struct device dev,
ab5f299f	338	unsigned long *freq, u32 flags)
a3c98b8b	339	{
5faaa035	340	return ERR_PTR(-EINVAL);
a3c98b8b MH	341	}
a3c98b8b MH	342
5faaa035	343	static inline int devfreq_register_opp_notifier(struct device *dev,
a3c98b8b MH	344	struct devfreq *devfreq)
	345	{
	346	return -EINVAL;
	347	}
	348
5faaa035	349	static inline int devfreq_unregister_opp_notifier(struct device *dev,
a3c98b8b MH	350	struct devfreq *devfreq)
	351	{
	352	return -EINVAL;
	353	}
	354
d5b040d0 CC	355	static inline int devm_devfreq_register_opp_notifier(struct device *dev,
	356	struct devfreq *devfreq)
	357	{
	358	return -EINVAL;
	359	}
	360
	361	static inline void devm_devfreq_unregister_opp_notifier(struct device *dev,
	362	struct devfreq *devfreq)
	363	{
	364	}
08e75e75	365
0fe3a664 CC	366	static inline int devfreq_register_notifier(struct devfreq *devfreq,
	367	struct notifier_block *nb,
	368	unsigned int list)
	369	{
	370	return 0;
	371	}
	372
	373	static inline int devfreq_unregister_notifier(struct devfreq *devfreq,
	374	struct notifier_block *nb,
	375	unsigned int list)
	376	{
	377	return 0;
	378	}
	379
	380	static inline int devm_devfreq_register_notifier(struct device *dev,
	381	struct devfreq *devfreq,
	382	struct notifier_block *nb,
	383	unsigned int list)
	384	{
	385	return 0;
	386	}
	387
	388	static inline void devm_devfreq_unregister_notifier(struct device *dev,
	389	struct devfreq *devfreq,
	390	struct notifier_block *nb,
	391	unsigned int list)
	392	{
	393	}
	394
8f510aeb CC	395	static inline struct devfreq devfreq_get_devfreq_by_phandle(struct device dev,
	396	int index)
	397	{
	398	return ERR_PTR(-ENODEV);
	399	}
	400
08e75e75 JM	401	static inline int devfreq_update_stats(struct devfreq *df)
	402	{
	403	return -EINVAL;
	404	}
a3c98b8b MH	405	#endif /* CONFIG_PM_DEVFREQ */
	406
	407	#endif /* __LINUX_DEVFREQ_H__ */