drivers/base/power/opp/opp.h

   1 /*
   2  * Generic OPP Interface
   3  *
   4  * Copyright (C) 2009-2010 Texas Instruments Incorporated.
   5  *      Nishanth Menon
   6  *      Romit Dasgupta
   7  *      Kevin Hilman
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License version 2 as
  11  * published by the Free Software Foundation.
  12  */
  13
  14 #ifndef __DRIVER_OPP_H__
  15 #define __DRIVER_OPP_H__
  16
  17 #include <linux/device.h>
  18 #include <linux/kernel.h>
  19 #include <linux/kref.h>
  20 #include <linux/list.h>
  21 #include <linux/limits.h>
  22 #include <linux/pm_opp.h>
  23 #include <linux/notifier.h>
  24
  25 struct clk;
  26 struct regulator;
  27
  28 /* Lock to allow exclusive modification to the device and opp lists */
  29 extern struct mutex opp_table_lock;
  30
  31 extern struct list_head opp_tables;
  32
  33 /*
  34  * Internal data structure organization with the OPP layer library is as
  35  * follows:
  36  * opp_tables (root)
  37  *      |- device 1 (represents voltage domain 1)
  38  *      |       |- opp 1 (availability, freq, voltage)
  39  *      |       |- opp 2 ..
  40  *      ...     ...
  41  *      |       `- opp n ..
  42  *      |- device 2 (represents the next voltage domain)
  43  *      ...
  44  *      `- device m (represents mth voltage domain)
  45  * device 1, 2.. are represented by opp_table structure while each opp
  46  * is represented by the opp structure.
  47  */
  48
  49 /**
  50  * struct dev_pm_opp - Generic OPP description structure
  51  * @node:       opp table node. The nodes are maintained throughout the lifetime
  52  *              of boot. It is expected only an optimal set of OPPs are
  53  *              added to the library by the SoC framework.
  54  *              IMPORTANT: the opp nodes should be maintained in increasing
  55  *              order.
  56  * @kref:       for reference count of the OPP.
  57  * @available:  true/false - marks if this OPP as available or not
  58  * @dynamic:    not-created from static DT entries.
  59  * @turbo:      true if turbo (boost) OPP
  60  * @suspend:    true if suspend OPP
  61  * @rate:       Frequency in hertz
  62  * @supplies:   Power supplies voltage/current values
  63  * @clock_latency_ns: Latency (in nanoseconds) of switching to this OPP's
  64  *              frequency from any other OPP's frequency.
  65  * @opp_table:  points back to the opp_table struct this opp belongs to
  66  * @np:         OPP's device node.
  67  * @dentry:     debugfs dentry pointer (per opp)
  68  *
  69  * This structure stores the OPP information for a given device.
  70  */
  71 struct dev_pm_opp {
  72         struct list_head node;
  73         struct kref kref;
  74
  75         bool available;
  76         bool dynamic;
  77         bool turbo;
  78         bool suspend;
  79         unsigned long rate;
  80
  81         struct dev_pm_opp_supply *supplies;
  82
  83         unsigned long clock_latency_ns;
  84
  85         struct opp_table *opp_table;
  86
  87         struct device_node *np;
  88
  89 #ifdef CONFIG_DEBUG_FS
  90         struct dentry *dentry;
  91 #endif
  92 };
  93
  94 /**
  95  * struct opp_device - devices managed by 'struct opp_table'
  96  * @node:       list node
  97  * @dev:        device to which the struct object belongs
  98  * @dentry:     debugfs dentry pointer (per device)
  99  *
 100  * This is an internal data structure maintaining the devices that are managed
 101  * by 'struct opp_table'.
 102  */
 103 struct opp_device {
 104         struct list_head node;
 105         const struct device *dev;
 106
 107 #ifdef CONFIG_DEBUG_FS
 108         struct dentry *dentry;
 109 #endif
 110 };
 111
 112 enum opp_table_access {
 113         OPP_TABLE_ACCESS_UNKNOWN = 0,
 114         OPP_TABLE_ACCESS_EXCLUSIVE = 1,
 115         OPP_TABLE_ACCESS_SHARED = 2,
 116 };
 117
 118 /**
 119  * struct opp_table - Device opp structure
 120  * @node:       table node - contains the devices with OPPs that
 121  *              have been registered. Nodes once added are not modified in this
 122  *              table.
 123  * @head:       notifier head to notify the OPP availability changes.
 124  * @dev_list:   list of devices that share these OPPs
 125  * @opp_list:   table of opps
 126  * @kref:       for reference count of the table.
 127  * @lock:       mutex protecting the opp_list.
 128  * @np:         struct device_node pointer for opp's DT node.
 129  * @clock_latency_ns_max: Max clock latency in nanoseconds.
 130  * @shared_opp: OPP is shared between multiple devices.
 131  * @suspend_opp: Pointer to OPP to be used during device suspend.
 132  * @supported_hw: Array of version number to support.
 133  * @supported_hw_count: Number of elements in supported_hw array.
 134  * @prop_name: A name to postfix to many DT properties, while parsing them.
 135  * @clk: Device's clock handle
 136  * @regulators: Supply regulators
 137  * @regulator_count: Number of power supply regulators
 138  * @set_opp: Platform specific set_opp callback
 139  * @set_opp_data: Data to be passed to set_opp callback
 140  * @dentry:     debugfs dentry pointer of the real device directory (not links).
 141  * @dentry_name: Name of the real dentry.
 142  *
 143  * @voltage_tolerance_v1: In percentage, for v1 bindings only.
 144  *
 145  * This is an internal data structure maintaining the link to opps attached to
 146  * a device. This structure is not meant to be shared to users as it is
 147  * meant for book keeping and private to OPP library.
 148  */
 149 struct opp_table {
 150         struct list_head node;
 151
 152         struct blocking_notifier_head head;
 153         struct list_head dev_list;
 154         struct list_head opp_list;
 155         struct kref kref;
 156         struct mutex lock;
 157
 158         struct device_node *np;
 159         unsigned long clock_latency_ns_max;
 160
 161         /* For backward compatibility with v1 bindings */
 162         unsigned int voltage_tolerance_v1;
 163
 164         enum opp_table_access shared_opp;
 165         struct dev_pm_opp *suspend_opp;
 166
 167         unsigned int *supported_hw;
 168         unsigned int supported_hw_count;
 169         const char *prop_name;
 170         struct clk *clk;
 171         struct regulator **regulators;
 172         unsigned int regulator_count;
 173
 174         int (*set_opp)(struct dev_pm_set_opp_data *data);
 175         struct dev_pm_set_opp_data *set_opp_data;
 176
 177 #ifdef CONFIG_DEBUG_FS
 178         struct dentry *dentry;
 179         char dentry_name[NAME_MAX];
 180 #endif
 181 };
 182
 183 /* Routines internal to opp core */
 184 void _get_opp_table_kref(struct opp_table *opp_table);
 185 struct opp_table *_find_opp_table(struct device *dev);
 186 struct opp_device *_add_opp_dev(const struct device *dev, struct opp_table *opp_table);
 187 void _dev_pm_opp_remove_table(struct opp_table *opp_table, struct device *dev, bool remove_all);
 188 void _dev_pm_opp_find_and_remove_table(struct device *dev, bool remove_all);
 189 struct dev_pm_opp *_opp_allocate(struct opp_table *opp_table);
 190 void _opp_free(struct dev_pm_opp *opp);
 191 int _opp_add(struct device *dev, struct dev_pm_opp *new_opp, struct opp_table *opp_table);
 192 int _opp_add_v1(struct opp_table *opp_table, struct device *dev, unsigned long freq, long u_volt, bool dynamic);
 193 void _dev_pm_opp_cpumask_remove_table(const struct cpumask *cpumask, bool of);
 194 struct opp_table *_add_opp_table(struct device *dev);
 195
 196 #ifdef CONFIG_OF
 197 void _of_init_opp_table(struct opp_table *opp_table, struct device *dev);
 198 #else
 199 static inline void _of_init_opp_table(struct opp_table *opp_table, struct device *dev) {}
 200 #endif
 201
 202 #ifdef CONFIG_DEBUG_FS
 203 void opp_debug_remove_one(struct dev_pm_opp *opp);
 204 int opp_debug_create_one(struct dev_pm_opp *opp, struct opp_table *opp_table);
 205 int opp_debug_register(struct opp_device *opp_dev, struct opp_table *opp_table);
 206 void opp_debug_unregister(struct opp_device *opp_dev, struct opp_table *opp_table);
 207 #else
 208 static inline void opp_debug_remove_one(struct dev_pm_opp *opp) {}
 209
 210 static inline int opp_debug_create_one(struct dev_pm_opp *opp,
 211                                        struct opp_table *opp_table)
 212 { return 0; }
 213 static inline int opp_debug_register(struct opp_device *opp_dev,
 214                                      struct opp_table *opp_table)
 215 { return 0; }
 216
 217 static inline void opp_debug_unregister(struct opp_device *opp_dev,
 218                                         struct opp_table *opp_table)
 219 { }
 220 #endif          /* DEBUG_FS */
 221
 222 #endif          /* __DRIVER_OPP_H__ */