/*
   * powercap.h: Data types and headers for sysfs power capping interface
   * Copyright (c) 2013, Intel Corporation.
   *
   * This program is free software; you can redistribute it and/or modify it
   * under the terms and conditions of the GNU General Public License,
   * version 2, as published by the Free Software Foundation.
   *
   * This program is distributed in the hope it will be useful, but WITHOUT
   * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
   * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
   * more details.
   *
   * You should have received a copy of the GNU General Public License along with
   * this program; if not, write to the Free Software Foundation, Inc.
   *
   */
  
  #ifndef __POWERCAP_H__
  #define __POWERCAP_H__
  
  #include <linux/device.h>
  #include <linux/idr.h>
  
  /*
   * A power cap class device can contain multiple powercap control_types.
   * Each control_type can have multiple power zones, which can be independently
   * controlled. Each power zone can have one or more constraints.
   */
  
  struct powercap_control_type;
  struct powercap_zone;
  struct powercap_zone_constraint;
  
  /**
   * struct powercap_control_type_ops - Define control type callbacks
   * @set_enable:		Enable/Disable whole control type.
   *			Default is enabled. But this callback allows all zones
   *			to be in disable state and remove any applied power
   *			limits. If disabled power zone can only be monitored
   *			not controlled.
   * @get_enable:		get Enable/Disable status.
   * @release:		Callback to inform that last reference to this
   *			control type is closed. So it is safe to free data
   *			structure associated with this control type.
   *			This callback is mandatory if the client own memory
   *			for the control type.
   *
   * This structure defines control type callbacks to be implemented by client
   * drivers
   */
  struct powercap_control_type_ops {
  	int (*set_enable) (struct powercap_control_type *, bool mode);
  	int (*get_enable) (struct powercap_control_type *, bool *mode);
  	int (*release) (struct powercap_control_type *);
  };
  
  /**
   * struct powercap_control_type- Defines a powercap control_type
   * @name:		name of control_type
   * @dev:		device for this control_type
   * @idr:		idr to have unique id for its child
   * @root_node:		Root holding power zones for this control_type
   * @ops:		Pointer to callback struct
   * @node_lock:		mutex for control type
   * @allocated:		This is possible that client owns the memory
   *			used by this structure. In this case
   *			this flag is set to false by framework to
   *			prevent deallocation during release process.
   *			Otherwise this flag is set to true.
   * @ctrl_inst:		link to the control_type list
   *
   * Defines powercap control_type. This acts as a container for power
   * zones, which use same method to control power. E.g. RAPL, RAPL-PCI etc.
   * All fields are private and should not be used by client drivers.
   */
  struct powercap_control_type {
  	struct device dev;
  	struct idr idr;
  	int nr_zones;
  	const struct powercap_control_type_ops *ops;
  	struct mutex lock;
  	bool allocated;
  	struct list_head node;
  };
  
  /**
   * struct powercap_zone_ops - Define power zone callbacks
   * @get_max_energy_range_uj:	Get maximum range of energy counter in
   *				micro-joules.
   * @get_energy_uj:		Get current energy counter in micro-joules.
   * @reset_energy_uj:		Reset micro-joules energy counter.
   * @get_max_power_range_uw:	Get maximum range of power counter in
   *				micro-watts.
   * @get_power_uw:		Get current power counter in micro-watts.
   * @set_enable:			Enable/Disable power zone controls.
   *				Default is enabled.
   * @get_enable:			get Enable/Disable status.
   * @release:			Callback to inform that last reference to this
   *				control type is closed. So it is safe to free
   *				data structure associated with this
   *				control type. Mandatory, if client driver owns
   *				the power_zone memory.
   *
   * This structure defines zone callbacks to be implemented by client drivers.
   * Client drives can define both energy and power related callbacks. But at
   * the least one type (either power or energy) is mandatory. Client drivers
   * should handle mutual exclusion, if required in callbacks.
   */
  struct powercap_zone_ops {
  	int (*get_max_energy_range_uj) (struct powercap_zone *, u64 *);
  	int (*get_energy_uj) (struct powercap_zone *, u64 *);
  	int (*reset_energy_uj) (struct powercap_zone *);
  	int (*get_max_power_range_uw) (struct powercap_zone *, u64 *);
  	int (*get_power_uw) (struct powercap_zone *, u64 *);
  	int (*set_enable) (struct powercap_zone *, bool mode);
  	int (*get_enable) (struct powercap_zone *, bool *mode);
  	int (*release) (struct powercap_zone *);
  };
  
  #define	POWERCAP_ZONE_MAX_ATTRS		6
  #define	POWERCAP_CONSTRAINTS_ATTRS	8
  #define MAX_CONSTRAINTS_PER_ZONE	10
  /**
   * struct powercap_zone- Defines instance of a power cap zone
   * @id:			Unique id
   * @name:		Power zone name.
   * @control_type_inst:	Control type instance for this zone.
   * @ops:		Pointer to the zone operation structure.
   * @dev:		Instance of a device.
   * @const_id_cnt:	Number of constraint defined.
   * @idr:		Instance to an idr entry for children zones.
   * @parent_idr:		To remove reference from the parent idr.
   * @private_data:	Private data pointer if any for this zone.
   * @zone_dev_attrs:	Attributes associated with this device.
   * @zone_attr_count:	Attribute count.
   * @dev_zone_attr_group: Attribute group for attributes.
   * @dev_attr_groups:	Attribute group store to register with device.
   * @allocated:		This is possible that client owns the memory
   *			used by this structure. In this case
   *			this flag is set to false by framework to
   *			prevent deallocation during release process.
   *			Otherwise this flag is set to true.
   * @constraint_ptr:	List of constraints for this zone.
   *
   * This defines a power zone instance. The fields of this structure are
   * private, and should not be used by client drivers.
   */
  struct powercap_zone {
  	int id;
  	char *name;
  	void *control_type_inst;
  	const struct powercap_zone_ops *ops;
  	struct device dev;
  	int const_id_cnt;
  	struct idr idr;
  	struct idr *parent_idr;
  	void *private_data;
  	struct attribute **zone_dev_attrs;
  	int zone_attr_count;
  	struct attribute_group dev_zone_attr_group;
  	const struct attribute_group *dev_attr_groups[2]; /* 1 group + NULL */
  	bool allocated;
  	struct powercap_zone_constraint *constraints;
  };
  
  /**
   * struct powercap_zone_constraint_ops - Define constraint callbacks
   * @set_power_limit_uw:		Set power limit in micro-watts.
   * @get_power_limit_uw:		Get power limit in micro-watts.
   * @set_time_window_us:		Set time window in micro-seconds.
   * @get_time_window_us:		Get time window in micro-seconds.
   * @get_max_power_uw:		Get max power allowed in micro-watts.
   * @get_min_power_uw:		Get min power allowed in micro-watts.
   * @get_max_time_window_us:	Get max time window allowed in micro-seconds.
   * @get_min_time_window_us:	Get min time window allowed in micro-seconds.
   * @get_name:			Get the name of constraint
   *
   * This structure is used to define the constraint callbacks for the client
   * drivers. The following callbacks are mandatory and can't be NULL:
   *  set_power_limit_uw
   *  get_power_limit_uw
   *  set_time_window_us
   *  get_time_window_us
   *  get_name
   *  Client drivers should handle mutual exclusion, if required in callbacks.
   */
  struct powercap_zone_constraint_ops {
  	int (*set_power_limit_uw) (struct powercap_zone *, int, u64);
  	int (*get_power_limit_uw) (struct powercap_zone *, int, u64 *);
  	int (*set_time_window_us) (struct powercap_zone *, int, u64);
  	int (*get_time_window_us) (struct powercap_zone *, int, u64 *);
  	int (*get_max_power_uw) (struct powercap_zone *, int, u64 *);
  	int (*get_min_power_uw) (struct powercap_zone *, int, u64 *);
  	int (*get_max_time_window_us) (struct powercap_zone *, int, u64 *);
  	int (*get_min_time_window_us) (struct powercap_zone *, int, u64 *);
  	const char *(*get_name) (struct powercap_zone *, int);
  };
  
  /**
   * struct powercap_zone_constraint- Defines instance of a constraint
   * @id:			Instance Id of this constraint.
   * @power_zone:		Pointer to the power zone for this constraint.
   * @ops:		Pointer to the constraint callbacks.
   *
   * This defines a constraint instance.
   */
  struct powercap_zone_constraint {
  	int id;
  	struct powercap_zone *power_zone;
  	struct powercap_zone_constraint_ops *ops;
  };
  
  
  /* For clients to get their device pointer, may be used for dev_dbgs */
  #define POWERCAP_GET_DEV(power_zone)	(&power_zone->dev)
  
  /**
  * powercap_set_zone_data() - Set private data for a zone
  * @power_zone:	A pointer to the valid zone instance.
  * @pdata:	A pointer to the user private data.
  *
  * Allows client drivers to associate some private data to zone instance.
  */
  static inline void powercap_set_zone_data(struct powercap_zone *power_zone,
  						void *pdata)
  {
  	if (power_zone)
  		power_zone->private_data = pdata;
  }
  
  /**
  * powercap_get_zone_data() - Get private data for a zone
  * @power_zone:	A pointer to the valid zone instance.
  *
  * Allows client drivers to get private data associate with a zone,
  * using call to powercap_set_zone_data.
  */
  static inline void *powercap_get_zone_data(struct powercap_zone *power_zone)
  {
  	if (power_zone)
  		return power_zone->private_data;
  	return NULL;
  }
  
  /**
  * powercap_register_control_type() - Register a control_type with framework
  * @control_type:	Pointer to client allocated memory for the control type
  *			structure storage. If this is NULL, powercap framework
  *			will allocate memory and own it.
  *			Advantage of this parameter is that client can embed
  *			this data in its data structures and allocate in a
  *			single call, preventing multiple allocations.
  * @control_type_name:	The Name of this control_type, which will be shown
  *			in the sysfs Interface.
  * @ops:			Callbacks for control type. This parameter is optional.
  *
  * Used to create a control_type with the power capping class. Here control_type
  * can represent a type of technology, which can control a range of power zones.
  * For example a control_type can be RAPL (Running Average Power Limit)
  * Intel® 64 and IA-32 Processor Architectures. The name can be any string
  * which must be unique, otherwise this function returns NULL.
  * A pointer to the control_type instance is returned on success.
  */
  struct powercap_control_type *powercap_register_control_type(
  				struct powercap_control_type *control_type,
  				const char *name,
  				const struct powercap_control_type_ops *ops);
  
  /**
  * powercap_unregister_control_type() - Unregister a control_type from framework
  * @instance:	A pointer to the valid control_type instance.
  *
  * Used to unregister a control_type with the power capping class.
  * All power zones registered under this control type have to be unregistered
  * before calling this function, or it will fail with an error code.
  */
  int powercap_unregister_control_type(struct powercap_control_type *instance);
  
  /* Zone register/unregister API */
  
  /**
  * powercap_register_zone() - Register a power zone
  * @power_zone:	Pointer to client allocated memory for the power zone structure
  *		storage. If this is NULL, powercap framework will allocate
  *		memory and own it. Advantage of this parameter is that client
  *		can embed this data in its data structures and allocate in a
  *		single call, preventing multiple allocations.
  * @control_type: A control_type instance under which this zone operates.
  * @name:	A name for this zone.
  * @parent:	A pointer to the parent power zone instance if any or NULL
  * @ops:		Pointer to zone operation callback structure.
  * @no_constraints: Number of constraints for this zone
  * @const_ops:	Pointer to constraint callback structure
  *
  * Register a power zone under a given control type. A power zone must register
  * a pointer to a structure representing zone callbacks.
  * A power zone can be located under a parent power zone, in which case @parent
  * should point to it.  Otherwise, if @parent is NULL, the new power zone will
  * be located directly under the given control type
  * For each power zone there may be a number of constraints that appear in the
  * sysfs under that zone as attributes with unique numeric IDs.
  * Returns pointer to the power_zone on success.
  */
  struct powercap_zone *powercap_register_zone(
  			struct powercap_zone *power_zone,
  			struct powercap_control_type *control_type,
  			const char *name,
  			struct powercap_zone *parent,
  			const struct powercap_zone_ops *ops,
  			int nr_constraints,
  			struct powercap_zone_constraint_ops *const_ops);
  
  /**
  * powercap_unregister_zone() - Unregister a zone device
  * @control_type:	A pointer to the valid instance of a control_type.
  * @power_zone:	A pointer to the valid zone instance for a control_type
  *
  * Used to unregister a zone device for a control_type.  Caller should
  * make sure that children for this zone are unregistered first.
  */
  int powercap_unregister_zone(struct powercap_control_type *control_type,
  				struct powercap_zone *power_zone);
  
  #endif