include/linux/scmi_protocol.h - linux - Git at Google

 /* SPDX-License-Identifier: GPL-2.0-only */
 /*
  * SCMI Message Protocol driver header
  *
  * Copyright (C) 2018 ARM Ltd.
  */

 #ifndef _LINUX_SCMI_PROTOCOL_H
 #define _LINUX_SCMI_PROTOCOL_H

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

 #define SCMI_MAX_STR_SIZE	16
 #define SCMI_MAX_NUM_RATES	16

 /**
  * struct scmi_revision_info - version information structure
  *
  * @major_ver: Major ABI version. Change here implies risk of backward
  *	compatibility break.
  * @minor_ver: Minor ABI version. Change here implies new feature addition,
  *	or compatible change in ABI.
  * @num_protocols: Number of protocols that are implemented, excluding the
  *	base protocol.
  * @num_agents: Number of agents in the system.
  * @impl_ver: A vendor-specific implementation version.
  * @vendor_id: A vendor identifier(Null terminated ASCII string)
  * @sub_vendor_id: A sub-vendor identifier(Null terminated ASCII string)
  */
 struct scmi_revision_info {
 	u16 major_ver;
 	u16 minor_ver;
 	u8 num_protocols;
 	u8 num_agents;
 	u32 impl_ver;
 	char vendor_id[SCMI_MAX_STR_SIZE];
 	char sub_vendor_id[SCMI_MAX_STR_SIZE];
 };

 struct scmi_clock_info {
 	char name[SCMI_MAX_STR_SIZE];
 	bool rate_discrete;
 	union {
 		struct {
 			int num_rates;
 			u64 rates[SCMI_MAX_NUM_RATES];
 		} list;
 		struct {
 			u64 min_rate;
 			u64 max_rate;
 			u64 step_size;
 		} range;
 	};
 };

 struct scmi_handle;

 /**
  * struct scmi_clk_ops - represents the various operations provided
  *	by SCMI Clock Protocol
  *
  * @count_get: get the count of clocks provided by SCMI
  * @info_get: get the information of the specified clock
  * @rate_get: request the current clock rate of a clock
  * @rate_set: set the clock rate of a clock
  * @enable: enables the specified clock
  * @disable: disables the specified clock
  */
 struct scmi_clk_ops {
 	int (*count_get)(const struct scmi_handle *handle);

 	const struct scmi_clock_info *(*info_get)
 		(const struct scmi_handle *handle, u32 clk_id);
 	int (*rate_get)(const struct scmi_handle *handle, u32 clk_id,
 			u64 *rate);
 	int (*rate_set)(const struct scmi_handle *handle, u32 clk_id,
 			u64 rate);
 	int (*enable)(const struct scmi_handle *handle, u32 clk_id);
 	int (*disable)(const struct scmi_handle *handle, u32 clk_id);
 };

 /**
  * struct scmi_perf_ops - represents the various operations provided
  *	by SCMI Performance Protocol
  *
  * @limits_set: sets limits on the performance level of a domain
  * @limits_get: gets limits on the performance level of a domain
  * @level_set: sets the performance level of a domain
  * @level_get: gets the performance level of a domain
  * @device_domain_id: gets the scmi domain id for a given device
  * @transition_latency_get: gets the DVFS transition latency for a given device
  * @device_opps_add: adds all the OPPs for a given device
  * @freq_set: sets the frequency for a given device using sustained frequency
  *	to sustained performance level mapping
  * @freq_get: gets the frequency for a given device using sustained frequency
  *	to sustained performance level mapping
  * @est_power_get: gets the estimated power cost for a given performance domain
  *	at a given frequency
  */
 struct scmi_perf_ops {
 	int (*limits_set)(const struct scmi_handle *handle, u32 domain,
 			  u32 max_perf, u32 min_perf);
 	int (*limits_get)(const struct scmi_handle *handle, u32 domain,
 			  u32 *max_perf, u32 *min_perf);
 	int (*level_set)(const struct scmi_handle *handle, u32 domain,
 			 u32 level, bool poll);
 	int (*level_get)(const struct scmi_handle *handle, u32 domain,
 			 u32 *level, bool poll);
 	int (*device_domain_id)(struct device *dev);
 	int (*transition_latency_get)(const struct scmi_handle *handle,
 				      struct device *dev);
 	int (*device_opps_add)(const struct scmi_handle *handle,
 			       struct device *dev);
 	int (*freq_set)(const struct scmi_handle *handle, u32 domain,
 			unsigned long rate, bool poll);
 	int (*freq_get)(const struct scmi_handle *handle, u32 domain,
 			unsigned long *rate, bool poll);
 	int (*est_power_get)(const struct scmi_handle *handle, u32 domain,
 			     unsigned long *rate, unsigned long *power);
 	bool (*fast_switch_possible)(const struct scmi_handle *handle,
 				     struct device *dev);
 };

 /**
  * struct scmi_power_ops - represents the various operations provided
  *	by SCMI Power Protocol
  *
  * @num_domains_get: get the count of power domains provided by SCMI
  * @name_get: gets the name of a power domain
  * @state_set: sets the power state of a power domain
  * @state_get: gets the power state of a power domain
  */
 struct scmi_power_ops {
 	int (*num_domains_get)(const struct scmi_handle *handle);
 	char *(*name_get)(const struct scmi_handle *handle, u32 domain);
 #define SCMI_POWER_STATE_TYPE_SHIFT	30
 #define SCMI_POWER_STATE_ID_MASK	(BIT(28) - 1)
 #define SCMI_POWER_STATE_PARAM(type, id) \
 	((((type) & BIT(0)) << SCMI_POWER_STATE_TYPE_SHIFT) | \
 		((id) & SCMI_POWER_STATE_ID_MASK))
 #define SCMI_POWER_STATE_GENERIC_ON	SCMI_POWER_STATE_PARAM(0, 0)
 #define SCMI_POWER_STATE_GENERIC_OFF	SCMI_POWER_STATE_PARAM(1, 0)
 	int (*state_set)(const struct scmi_handle *handle, u32 domain,
 			 u32 state);
 	int (*state_get)(const struct scmi_handle *handle, u32 domain,
 			 u32 *state);
 };

 struct scmi_sensor_info {
 	u32 id;
 	u8 type;
 	s8 scale;
 	u8 num_trip_points;
 	bool async;
 	char name[SCMI_MAX_STR_SIZE];
 };

 /*
  * Partial list from Distributed Management Task Force (DMTF) specification:
  * DSP0249 (Platform Level Data Model specification)
  */
 enum scmi_sensor_class {
 	NONE = 0x0,
 	TEMPERATURE_C = 0x2,
 	VOLTAGE = 0x5,
 	CURRENT = 0x6,
 	POWER = 0x7,
 	ENERGY = 0x8,
 };

 /**
  * struct scmi_sensor_ops - represents the various operations provided
  *	by SCMI Sensor Protocol
  *
  * @count_get: get the count of sensors provided by SCMI
  * @info_get: get the information of the specified sensor
  * @trip_point_config: selects and configures a trip-point of interest
  * @reading_get: gets the current value of the sensor
  */
 struct scmi_sensor_ops {
 	int (*count_get)(const struct scmi_handle *handle);
 	const struct scmi_sensor_info *(*info_get)
 		(const struct scmi_handle *handle, u32 sensor_id);
 	int (*trip_point_config)(const struct scmi_handle *handle,
 				 u32 sensor_id, u8 trip_id, u64 trip_value);
 	int (*reading_get)(const struct scmi_handle *handle, u32 sensor_id,
 			   u64 *value);
 };

 /**
  * struct scmi_reset_ops - represents the various operations provided
  *	by SCMI Reset Protocol
  *
  * @num_domains_get: get the count of reset domains provided by SCMI
  * @name_get: gets the name of a reset domain
  * @latency_get: gets the reset latency for the specified reset domain
  * @reset: resets the specified reset domain
  * @assert: explicitly assert reset signal of the specified reset domain
  * @deassert: explicitly deassert reset signal of the specified reset domain
  */
 struct scmi_reset_ops {
 	int (*num_domains_get)(const struct scmi_handle *handle);
 	char *(*name_get)(const struct scmi_handle *handle, u32 domain);
 	int (*latency_get)(const struct scmi_handle *handle, u32 domain);
 	int (*reset)(const struct scmi_handle *handle, u32 domain);
 	int (*assert)(const struct scmi_handle *handle, u32 domain);
 	int (*deassert)(const struct scmi_handle *handle, u32 domain);
 };

 /**
  * struct scmi_notify_ops  - represents notifications' operations provided by
  * SCMI core
  * @register_event_notifier: Register a notifier_block for the requested event
  * @unregister_event_notifier: Unregister a notifier_block for the requested
  *			       event
  *
  * A user can register/unregister its own notifier_block against the wanted
  * platform instance regarding the desired event identified by the
  * tuple: (proto_id, evt_id, src_id) using the provided register/unregister
  * interface where:
  *
  * @handle: The handle identifying the platform instance to use
  * @proto_id: The protocol ID as in SCMI Specification
  * @evt_id: The message ID of the desired event as in SCMI Specification
  * @src_id: A pointer to the desired source ID if different sources are
  *	    possible for the protocol (like domain_id, sensor_id...etc)
  *
  * @src_id can be provided as NULL if it simply does NOT make sense for
  * the protocol at hand, OR if the user is explicitly interested in
  * receiving notifications from ANY existent source associated to the
  * specified proto_id / evt_id.
  *
  * Received notifications are finally delivered to the registered users,
  * invoking the callback provided with the notifier_block *nb as follows:
  *
  *	int user_cb(nb, evt_id, report)
  *
  * with:
  *
  * @nb: The notifier block provided by the user
  * @evt_id: The message ID of the delivered event
  * @report: A custom struct describing the specific event delivered
  */
 struct scmi_notify_ops {
 	int (*register_event_notifier)(const struct scmi_handle *handle,
 				       u8 proto_id, u8 evt_id, u32 *src_id,
 				       struct notifier_block *nb);
 	int (*unregister_event_notifier)(const struct scmi_handle *handle,
 					 u8 proto_id, u8 evt_id, u32 *src_id,
 					 struct notifier_block *nb);
 };

 /**
  * struct scmi_handle - Handle returned to ARM SCMI clients for usage.
  *
  * @dev: pointer to the SCMI device
  * @version: pointer to the structure containing SCMI version information
  * @power_ops: pointer to set of power protocol operations
  * @perf_ops: pointer to set of performance protocol operations
  * @clk_ops: pointer to set of clock protocol operations
  * @sensor_ops: pointer to set of sensor protocol operations
  * @reset_ops: pointer to set of reset protocol operations
  * @notify_ops: pointer to set of notifications related operations
  * @perf_priv: pointer to private data structure specific to performance
  *	protocol(for internal use only)
  * @clk_priv: pointer to private data structure specific to clock
  *	protocol(for internal use only)
  * @power_priv: pointer to private data structure specific to power
  *	protocol(for internal use only)
  * @sensor_priv: pointer to private data structure specific to sensors
  *	protocol(for internal use only)
  * @reset_priv: pointer to private data structure specific to reset
  *	protocol(for internal use only)
  * @notify_priv: pointer to private data structure specific to notifications
  *	(for internal use only)
  */
 struct scmi_handle {
 	struct device *dev;
 	struct scmi_revision_info *version;
 	struct scmi_perf_ops *perf_ops;
 	struct scmi_clk_ops *clk_ops;
 	struct scmi_power_ops *power_ops;
 	struct scmi_sensor_ops *sensor_ops;
 	struct scmi_reset_ops *reset_ops;
 	struct scmi_notify_ops *notify_ops;
 	/* for protocol internal use */
 	void *perf_priv;
 	void *clk_priv;
 	void *power_priv;
 	void *sensor_priv;
 	void *reset_priv;
 	void *notify_priv;
 };

 enum scmi_std_protocol {
 	SCMI_PROTOCOL_BASE = 0x10,
 	SCMI_PROTOCOL_POWER = 0x11,
 	SCMI_PROTOCOL_SYSTEM = 0x12,
 	SCMI_PROTOCOL_PERF = 0x13,
 	SCMI_PROTOCOL_CLOCK = 0x14,
 	SCMI_PROTOCOL_SENSOR = 0x15,
 	SCMI_PROTOCOL_RESET = 0x16,
 };

 struct scmi_device {
 	u32 id;
 	u8 protocol_id;
 	const char *name;
 	struct device dev;
 	struct scmi_handle *handle;
 };

 #define to_scmi_dev(d) container_of(d, struct scmi_device, dev)

 struct scmi_device *
 scmi_device_create(struct device_node *np, struct device *parent, int protocol,
 		   const char *name);
 void scmi_device_destroy(struct scmi_device *scmi_dev);

 struct scmi_device_id {
 	u8 protocol_id;
 	const char *name;
 };

 struct scmi_driver {
 	const char *name;
 	int (*probe)(struct scmi_device *sdev);
 	void (*remove)(struct scmi_device *sdev);
 	const struct scmi_device_id *id_table;

 	struct device_driver driver;
 };

 #define to_scmi_driver(d) container_of(d, struct scmi_driver, driver)

 #ifdef CONFIG_ARM_SCMI_PROTOCOL
 int scmi_driver_register(struct scmi_driver *driver,
 			 struct module *owner, const char *mod_name);
 void scmi_driver_unregister(struct scmi_driver *driver);
 #else
 static inline int
 scmi_driver_register(struct scmi_driver *driver, struct module *owner,
 		     const char *mod_name)
 {
 	return -EINVAL;
 }

 static inline void scmi_driver_unregister(struct scmi_driver *driver) {}
 #endif /* CONFIG_ARM_SCMI_PROTOCOL */

 #define scmi_register(driver) \
 	scmi_driver_register(driver, THIS_MODULE, KBUILD_MODNAME)
 #define scmi_unregister(driver) \
 	scmi_driver_unregister(driver)

 /**
  * module_scmi_driver() - Helper macro for registering a scmi driver
  * @__scmi_driver: scmi_driver structure
  *
  * Helper macro for scmi drivers to set up proper module init / exit
  * functions.  Replaces module_init() and module_exit() and keeps people from
  * printing pointless things to the kernel log when their driver is loaded.
  */
 #define module_scmi_driver(__scmi_driver)	\
 	module_driver(__scmi_driver, scmi_register, scmi_unregister)

 typedef int (*scmi_prot_init_fn_t)(struct scmi_handle *);
 int scmi_protocol_register(int protocol_id, scmi_prot_init_fn_t fn);
 void scmi_protocol_unregister(int protocol_id);

 /* SCMI Notification API - Custom Event Reports */
 enum scmi_notification_events {
 	SCMI_EVENT_POWER_STATE_CHANGED = 0x0,
 	SCMI_EVENT_PERFORMANCE_LIMITS_CHANGED = 0x0,
 	SCMI_EVENT_PERFORMANCE_LEVEL_CHANGED = 0x1,
 	SCMI_EVENT_SENSOR_TRIP_POINT_EVENT = 0x0,
 	SCMI_EVENT_RESET_ISSUED = 0x0,
 	SCMI_EVENT_BASE_ERROR_EVENT = 0x0,
 };

 struct scmi_power_state_changed_report {
 	ktime_t		timestamp;
 	unsigned int	agent_id;
 	unsigned int	domain_id;
 	unsigned int	power_state;
 };

 struct scmi_perf_limits_report {
 	ktime_t		timestamp;
 	unsigned int	agent_id;
 	unsigned int	domain_id;
 	unsigned int	range_max;
 	unsigned int	range_min;
 };

 struct scmi_perf_level_report {
 	ktime_t		timestamp;
 	unsigned int	agent_id;
 	unsigned int	domain_id;
 	unsigned int	performance_level;
 };

 struct scmi_sensor_trip_point_report {
 	ktime_t		timestamp;
 	unsigned int	agent_id;
 	unsigned int	sensor_id;
 	unsigned int	trip_point_desc;
 };

 struct scmi_reset_issued_report {
 	ktime_t		timestamp;
 	unsigned int	agent_id;
 	unsigned int	domain_id;
 	unsigned int	reset_state;
 };

 struct scmi_base_error_report {
 	ktime_t			timestamp;
 	unsigned int		agent_id;
 	bool			fatal;
 	unsigned int		cmd_count;
 	unsigned long long	reports[];
 };

 #endif /* _LINUX_SCMI_PROTOCOL_H */
	/* SPDX-License-Identifier: GPL-2.0-only */
	/*
	* SCMI Message Protocol driver header
	*
	* Copyright (C) 2018 ARM Ltd.
	*/

	#ifndef _LINUX_SCMI_PROTOCOL_H
	#define _LINUX_SCMI_PROTOCOL_H

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

	#define SCMI_MAX_STR_SIZE 16
	#define SCMI_MAX_NUM_RATES 16

	/**
	* struct scmi_revision_info - version information structure
	*
	* @major_ver: Major ABI version. Change here implies risk of backward
	* compatibility break.
	* @minor_ver: Minor ABI version. Change here implies new feature addition,
	* or compatible change in ABI.
	* @num_protocols: Number of protocols that are implemented, excluding the
	* base protocol.
	* @num_agents: Number of agents in the system.
	* @impl_ver: A vendor-specific implementation version.
	* @vendor_id: A vendor identifier(Null terminated ASCII string)
	* @sub_vendor_id: A sub-vendor identifier(Null terminated ASCII string)
	*/
	struct scmi_revision_info {
	u16 major_ver;
	u16 minor_ver;
	u8 num_protocols;
	u8 num_agents;
	u32 impl_ver;
	char vendor_id[SCMI_MAX_STR_SIZE];
	char sub_vendor_id[SCMI_MAX_STR_SIZE];
	};

	struct scmi_clock_info {
	char name[SCMI_MAX_STR_SIZE];
	bool rate_discrete;
	union {
	struct {
	int num_rates;
	u64 rates[SCMI_MAX_NUM_RATES];
	} list;
	struct {
	u64 min_rate;
	u64 max_rate;
	u64 step_size;
	} range;
	};
	};

	struct scmi_handle;

	/**
	* struct scmi_clk_ops - represents the various operations provided
	* by SCMI Clock Protocol
	*
	* @count_get: get the count of clocks provided by SCMI
	* @info_get: get the information of the specified clock
	* @rate_get: request the current clock rate of a clock
	* @rate_set: set the clock rate of a clock
	* @enable: enables the specified clock
	* @disable: disables the specified clock
	*/
	struct scmi_clk_ops {
	int (count_get)(const struct scmi_handle handle);

	const struct scmi_clock_info (info_get)
	(const struct scmi_handle *handle, u32 clk_id);
	int (rate_get)(const struct scmi_handle handle, u32 clk_id,
	u64 *rate);
	int (rate_set)(const struct scmi_handle handle, u32 clk_id,
	u64 rate);
	int (enable)(const struct scmi_handle handle, u32 clk_id);
	int (disable)(const struct scmi_handle handle, u32 clk_id);
	};

	/**
	* struct scmi_perf_ops - represents the various operations provided
	* by SCMI Performance Protocol
	*
	* @limits_set: sets limits on the performance level of a domain
	* @limits_get: gets limits on the performance level of a domain
	* @level_set: sets the performance level of a domain
	* @level_get: gets the performance level of a domain
	* @device_domain_id: gets the scmi domain id for a given device
	* @transition_latency_get: gets the DVFS transition latency for a given device
	* @device_opps_add: adds all the OPPs for a given device
	* @freq_set: sets the frequency for a given device using sustained frequency
	* to sustained performance level mapping
	* @freq_get: gets the frequency for a given device using sustained frequency
	* to sustained performance level mapping
	* @est_power_get: gets the estimated power cost for a given performance domain
	* at a given frequency
	*/
	struct scmi_perf_ops {
	int (limits_set)(const struct scmi_handle handle, u32 domain,
	u32 max_perf, u32 min_perf);
	int (limits_get)(const struct scmi_handle handle, u32 domain,
	u32 max_perf, u32 min_perf);
	int (level_set)(const struct scmi_handle handle, u32 domain,
	u32 level, bool poll);
	int (level_get)(const struct scmi_handle handle, u32 domain,
	u32 *level, bool poll);
	int (device_domain_id)(struct device dev);
	int (transition_latency_get)(const struct scmi_handle handle,
	struct device *dev);
	int (device_opps_add)(const struct scmi_handle handle,
	struct device *dev);
	int (freq_set)(const struct scmi_handle handle, u32 domain,
	unsigned long rate, bool poll);
	int (freq_get)(const struct scmi_handle handle, u32 domain,
	unsigned long *rate, bool poll);
	int (est_power_get)(const struct scmi_handle handle, u32 domain,
	unsigned long rate, unsigned long power);
	bool (fast_switch_possible)(const struct scmi_handle handle,
	struct device *dev);
	};

	/**
	* struct scmi_power_ops - represents the various operations provided
	* by SCMI Power Protocol
	*
	* @num_domains_get: get the count of power domains provided by SCMI
	* @name_get: gets the name of a power domain
	* @state_set: sets the power state of a power domain
	* @state_get: gets the power state of a power domain
	*/
	struct scmi_power_ops {
	int (num_domains_get)(const struct scmi_handle handle);
	char (name_get)(const struct scmi_handle *handle, u32 domain);
	#define SCMI_POWER_STATE_TYPE_SHIFT 30
	#define SCMI_POWER_STATE_ID_MASK (BIT(28) - 1)
	#define SCMI_POWER_STATE_PARAM(type, id) \
	((((type) & BIT(0)) << SCMI_POWER_STATE_TYPE_SHIFT) \| \
	((id) & SCMI_POWER_STATE_ID_MASK))
	#define SCMI_POWER_STATE_GENERIC_ON SCMI_POWER_STATE_PARAM(0, 0)
	#define SCMI_POWER_STATE_GENERIC_OFF SCMI_POWER_STATE_PARAM(1, 0)
	int (state_set)(const struct scmi_handle handle, u32 domain,
	u32 state);
	int (state_get)(const struct scmi_handle handle, u32 domain,
	u32 *state);
	};

	struct scmi_sensor_info {
	u32 id;
	u8 type;
	s8 scale;
	u8 num_trip_points;
	bool async;
	char name[SCMI_MAX_STR_SIZE];
	};

	/*
	* Partial list from Distributed Management Task Force (DMTF) specification:
	* DSP0249 (Platform Level Data Model specification)
	*/
	enum scmi_sensor_class {
	NONE = 0x0,
	TEMPERATURE_C = 0x2,
	VOLTAGE = 0x5,
	CURRENT = 0x6,
	POWER = 0x7,
	ENERGY = 0x8,
	};

	/**
	* struct scmi_sensor_ops - represents the various operations provided
	* by SCMI Sensor Protocol
	*
	* @count_get: get the count of sensors provided by SCMI
	* @info_get: get the information of the specified sensor
	* @trip_point_config: selects and configures a trip-point of interest
	* @reading_get: gets the current value of the sensor
	*/
	struct scmi_sensor_ops {
	int (count_get)(const struct scmi_handle handle);
	const struct scmi_sensor_info (info_get)
	(const struct scmi_handle *handle, u32 sensor_id);
	int (trip_point_config)(const struct scmi_handle handle,
	u32 sensor_id, u8 trip_id, u64 trip_value);
	int (reading_get)(const struct scmi_handle handle, u32 sensor_id,
	u64 *value);
	};

	/**
	* struct scmi_reset_ops - represents the various operations provided
	* by SCMI Reset Protocol
	*
	* @num_domains_get: get the count of reset domains provided by SCMI
	* @name_get: gets the name of a reset domain
	* @latency_get: gets the reset latency for the specified reset domain
	* @reset: resets the specified reset domain
	* @assert: explicitly assert reset signal of the specified reset domain
	* @deassert: explicitly deassert reset signal of the specified reset domain
	*/
	struct scmi_reset_ops {
	int (num_domains_get)(const struct scmi_handle handle);
	char (name_get)(const struct scmi_handle *handle, u32 domain);
	int (latency_get)(const struct scmi_handle handle, u32 domain);
	int (reset)(const struct scmi_handle handle, u32 domain);
	int (assert)(const struct scmi_handle handle, u32 domain);
	int (deassert)(const struct scmi_handle handle, u32 domain);
	};

	/**
	* struct scmi_notify_ops - represents notifications' operations provided by
	* SCMI core
	* @register_event_notifier: Register a notifier_block for the requested event
	* @unregister_event_notifier: Unregister a notifier_block for the requested
	* event
	*
	* A user can register/unregister its own notifier_block against the wanted
	* platform instance regarding the desired event identified by the
	* tuple: (proto_id, evt_id, src_id) using the provided register/unregister
	* interface where:
	*
	* @handle: The handle identifying the platform instance to use
	* @proto_id: The protocol ID as in SCMI Specification
	* @evt_id: The message ID of the desired event as in SCMI Specification
	* @src_id: A pointer to the desired source ID if different sources are
	* possible for the protocol (like domain_id, sensor_id...etc)
	*
	* @src_id can be provided as NULL if it simply does NOT make sense for
	* the protocol at hand, OR if the user is explicitly interested in
	* receiving notifications from ANY existent source associated to the
	* specified proto_id / evt_id.
	*
	* Received notifications are finally delivered to the registered users,
	* invoking the callback provided with the notifier_block *nb as follows:
	*
	* int user_cb(nb, evt_id, report)
	*
	* with:
	*
	* @nb: The notifier block provided by the user
	* @evt_id: The message ID of the delivered event
	* @report: A custom struct describing the specific event delivered
	*/
	struct scmi_notify_ops {
	int (register_event_notifier)(const struct scmi_handle handle,
	u8 proto_id, u8 evt_id, u32 *src_id,
	struct notifier_block *nb);
	int (unregister_event_notifier)(const struct scmi_handle handle,
	u8 proto_id, u8 evt_id, u32 *src_id,
	struct notifier_block *nb);
	};

	/**
	* struct scmi_handle - Handle returned to ARM SCMI clients for usage.
	*
	* @dev: pointer to the SCMI device
	* @version: pointer to the structure containing SCMI version information
	* @power_ops: pointer to set of power protocol operations
	* @perf_ops: pointer to set of performance protocol operations
	* @clk_ops: pointer to set of clock protocol operations
	* @sensor_ops: pointer to set of sensor protocol operations
	* @reset_ops: pointer to set of reset protocol operations
	* @notify_ops: pointer to set of notifications related operations
	* @perf_priv: pointer to private data structure specific to performance
	* protocol(for internal use only)
	* @clk_priv: pointer to private data structure specific to clock
	* protocol(for internal use only)
	* @power_priv: pointer to private data structure specific to power
	* protocol(for internal use only)
	* @sensor_priv: pointer to private data structure specific to sensors
	* protocol(for internal use only)
	* @reset_priv: pointer to private data structure specific to reset
	* protocol(for internal use only)
	* @notify_priv: pointer to private data structure specific to notifications
	* (for internal use only)
	*/
	struct scmi_handle {
	struct device *dev;
	struct scmi_revision_info *version;
	struct scmi_perf_ops *perf_ops;
	struct scmi_clk_ops *clk_ops;
	struct scmi_power_ops *power_ops;
	struct scmi_sensor_ops *sensor_ops;
	struct scmi_reset_ops *reset_ops;
	struct scmi_notify_ops *notify_ops;
	/* for protocol internal use */
	void *perf_priv;
	void *clk_priv;
	void *power_priv;
	void *sensor_priv;
	void *reset_priv;
	void *notify_priv;
	};

	enum scmi_std_protocol {
	SCMI_PROTOCOL_BASE = 0x10,
	SCMI_PROTOCOL_POWER = 0x11,
	SCMI_PROTOCOL_SYSTEM = 0x12,
	SCMI_PROTOCOL_PERF = 0x13,
	SCMI_PROTOCOL_CLOCK = 0x14,
	SCMI_PROTOCOL_SENSOR = 0x15,
	SCMI_PROTOCOL_RESET = 0x16,
	};

	struct scmi_device {
	u32 id;
	u8 protocol_id;
	const char *name;
	struct device dev;
	struct scmi_handle *handle;
	};

	#define to_scmi_dev(d) container_of(d, struct scmi_device, dev)

	struct scmi_device *
	scmi_device_create(struct device_node np, struct device parent, int protocol,
	const char *name);
	void scmi_device_destroy(struct scmi_device *scmi_dev);

	struct scmi_device_id {
	u8 protocol_id;
	const char *name;
	};

	struct scmi_driver {
	const char *name;
	int (probe)(struct scmi_device sdev);
	void (remove)(struct scmi_device sdev);
	const struct scmi_device_id *id_table;

	struct device_driver driver;
	};

	#define to_scmi_driver(d) container_of(d, struct scmi_driver, driver)

	#ifdef CONFIG_ARM_SCMI_PROTOCOL
	int scmi_driver_register(struct scmi_driver *driver,
	struct module owner, const char mod_name);
	void scmi_driver_unregister(struct scmi_driver *driver);
	#else
	static inline int
	scmi_driver_register(struct scmi_driver driver, struct module owner,
	const char *mod_name)
	{
	return -EINVAL;
	}

	static inline void scmi_driver_unregister(struct scmi_driver *driver) {}
	#endif /* CONFIG_ARM_SCMI_PROTOCOL */

	#define scmi_register(driver) \
	scmi_driver_register(driver, THIS_MODULE, KBUILD_MODNAME)
	#define scmi_unregister(driver) \
	scmi_driver_unregister(driver)

	/**
	* module_scmi_driver() - Helper macro for registering a scmi driver
	* @__scmi_driver: scmi_driver structure
	*
	* Helper macro for scmi drivers to set up proper module init / exit
	* functions. Replaces module_init() and module_exit() and keeps people from
	* printing pointless things to the kernel log when their driver is loaded.
	*/
	#define module_scmi_driver(__scmi_driver) \
	module_driver(__scmi_driver, scmi_register, scmi_unregister)

	typedef int (scmi_prot_init_fn_t)(struct scmi_handle );
	int scmi_protocol_register(int protocol_id, scmi_prot_init_fn_t fn);
	void scmi_protocol_unregister(int protocol_id);

	/* SCMI Notification API - Custom Event Reports */
	enum scmi_notification_events {
	SCMI_EVENT_POWER_STATE_CHANGED = 0x0,
	SCMI_EVENT_PERFORMANCE_LIMITS_CHANGED = 0x0,
	SCMI_EVENT_PERFORMANCE_LEVEL_CHANGED = 0x1,
	SCMI_EVENT_SENSOR_TRIP_POINT_EVENT = 0x0,
	SCMI_EVENT_RESET_ISSUED = 0x0,
	SCMI_EVENT_BASE_ERROR_EVENT = 0x0,
	};

	struct scmi_power_state_changed_report {
	ktime_t timestamp;
	unsigned int agent_id;
	unsigned int domain_id;
	unsigned int power_state;
	};

	struct scmi_perf_limits_report {
	ktime_t timestamp;
	unsigned int agent_id;
	unsigned int domain_id;
	unsigned int range_max;
	unsigned int range_min;
	};

	struct scmi_perf_level_report {
	ktime_t timestamp;
	unsigned int agent_id;
	unsigned int domain_id;
	unsigned int performance_level;
	};

	struct scmi_sensor_trip_point_report {
	ktime_t timestamp;
	unsigned int agent_id;
	unsigned int sensor_id;
	unsigned int trip_point_desc;
	};

	struct scmi_reset_issued_report {
	ktime_t timestamp;
	unsigned int agent_id;
	unsigned int domain_id;
	unsigned int reset_state;
	};

	struct scmi_base_error_report {
	ktime_t timestamp;
	unsigned int agent_id;
	bool fatal;
	unsigned int cmd_count;
	unsigned long long reports[];
	};

	#endif /* _LINUX_SCMI_PROTOCOL_H */