include/linux/regmap.h

   1 #ifndef __LINUX_REGMAP_H
   2 #define __LINUX_REGMAP_H
   3
   4 /*
   5  * Register map access API
   6  *
   7  * Copyright 2011 Wolfson Microelectronics plc
   8  *
   9  * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
  10  *
  11  * This program is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License version 2 as
  13  * published by the Free Software Foundation.
  14  */
  15
  16 #include <linux/device.h>
  17 #include <linux/list.h>
  18
  19 struct module;
  20 struct i2c_client;
  21 struct spi_device;
  22
  23 /* An enum of all the supported cache types */
  24 enum regcache_type {
  25         REGCACHE_NONE,
  26         REGCACHE_RBTREE,
  27         REGCACHE_COMPRESSED
  28 };
  29
  30 /**
  31  * Default value for a register.  We use an array of structs rather
  32  * than a simple array as many modern devices have very sparse
  33  * register maps.
  34  *
  35  * @reg: Register address.
  36  * @def: Register default value.
  37  */
  38 struct reg_default {
  39         unsigned int reg;
  40         unsigned int def;
  41 };
  42
  43 /**
  44  * Configuration for the register map of a device.
  45  *
  46  * @reg_bits: Number of bits in a register address, mandatory.
  47  * @val_bits: Number of bits in a register value, mandatory.
  48  *
  49  * @writeable_reg: Optional callback returning true if the register
  50  *                 can be written to.
  51  * @readable_reg: Optional callback returning true if the register
  52  *                can be read from.
  53  * @volatile_reg: Optional callback returning true if the register
  54  *                value can't be cached.
  55  * @precious_reg: Optional callback returning true if the rgister
  56  *                should not be read outside of a call from the driver
  57  *                (eg, a clear on read interrupt status register).
  58  *
  59  * @max_register: Optional, specifies the maximum valid register index.
  60  * @reg_defaults: Power on reset values for registers (for use with
  61  *                register cache support).
  62  * @num_reg_defaults: Number of elements in reg_defaults.
  63  *
  64  * @read_flag_mask: Mask to be set in the top byte of the register when doing
  65  *                  a read.
  66  * @write_flag_mask: Mask to be set in the top byte of the register when doing
  67  *                   a write. If both read_flag_mask and write_flag_mask are
  68  *                   empty the regmap_bus default masks are used.
  69  *
  70  * @cache_type: The actual cache type.
  71  * @reg_defaults_raw: Power on reset values for registers (for use with
  72  *                    register cache support).
  73  * @num_reg_defaults_raw: Number of elements in reg_defaults_raw.
  74  */
  75 struct regmap_config {
  76         int reg_bits;
  77         int val_bits;
  78
  79         bool (*writeable_reg)(struct device *dev, unsigned int reg);
  80         bool (*readable_reg)(struct device *dev, unsigned int reg);
  81         bool (*volatile_reg)(struct device *dev, unsigned int reg);
  82         bool (*precious_reg)(struct device *dev, unsigned int reg);
  83
  84         unsigned int max_register;
  85         const struct reg_default *reg_defaults;
  86         unsigned int num_reg_defaults;
  87         enum regcache_type cache_type;
  88         const void *reg_defaults_raw;
  89         unsigned int num_reg_defaults_raw;
  90
  91         u8 read_flag_mask;
  92         u8 write_flag_mask;
  93 };
  94
  95 typedef int (*regmap_hw_write)(struct device *dev, const void *data,
  96                                size_t count);
  97 typedef int (*regmap_hw_gather_write)(struct device *dev,
  98                                       const void *reg, size_t reg_len,
  99                                       const void *val, size_t val_len);
 100 typedef int (*regmap_hw_read)(struct device *dev,
 101                               const void *reg_buf, size_t reg_size,
 102                               void *val_buf, size_t val_size);
 103
 104 /**
 105  * Description of a hardware bus for the register map infrastructure.
 106  *
 107  * @write: Write operation.
 108  * @gather_write: Write operation with split register/value, return -ENOTSUPP
 109  *                if not implemented  on a given device.
 110  * @read: Read operation.  Data is returned in the buffer used to transmit
 111  *         data.
 112  * @read_flag_mask: Mask to be set in the top byte of the register when doing
 113  *                  a read.
 114  */
 115 struct regmap_bus {
 116         regmap_hw_write write;
 117         regmap_hw_gather_write gather_write;
 118         regmap_hw_read read;
 119         u8 read_flag_mask;
 120 };
 121
 122 struct regmap *regmap_init(struct device *dev,
 123                            const struct regmap_bus *bus,
 124                            const struct regmap_config *config);
 125 struct regmap *regmap_init_i2c(struct i2c_client *i2c,
 126                                const struct regmap_config *config);
 127 struct regmap *regmap_init_spi(struct spi_device *dev,
 128                                const struct regmap_config *config);
 129
 130 void regmap_exit(struct regmap *map);
 131 int regmap_reinit_cache(struct regmap *map,
 132                         const struct regmap_config *config);
 133 int regmap_write(struct regmap *map, unsigned int reg, unsigned int val);
 134 int regmap_raw_write(struct regmap *map, unsigned int reg,
 135                      const void *val, size_t val_len);
 136 int regmap_read(struct regmap *map, unsigned int reg, unsigned int *val);
 137 int regmap_raw_read(struct regmap *map, unsigned int reg,
 138                     void *val, size_t val_len);
 139 int regmap_bulk_read(struct regmap *map, unsigned int reg, void *val,
 140                      size_t val_count);
 141 int regmap_update_bits(struct regmap *map, unsigned int reg,
 142                        unsigned int mask, unsigned int val);
 143 int regmap_update_bits_check(struct regmap *map, unsigned int reg,
 144                              unsigned int mask, unsigned int val,
 145                              bool *change);
 146
 147 int regcache_sync(struct regmap *map);
 148 void regcache_cache_only(struct regmap *map, bool enable);
 149 void regcache_cache_bypass(struct regmap *map, bool enable);
 150 void regcache_mark_dirty(struct regmap *map);
 151
 152 /**
 153  * Description of an IRQ for the generic regmap irq_chip.
 154  *
 155  * @reg_offset: Offset of the status/mask register within the bank
 156  * @mask:       Mask used to flag/control the register.
 157  */
 158 struct regmap_irq {
 159         unsigned int reg_offset;
 160         unsigned int mask;
 161 };
 162
 163 /**
 164  * Description of a generic regmap irq_chip.  This is not intended to
 165  * handle every possible interrupt controller, but it should handle a
 166  * substantial proportion of those that are found in the wild.
 167  *
 168  * @name:        Descriptive name for IRQ controller.
 169  *
 170  * @status_base: Base status register address.
 171  * @mask_base:   Base mask register address.
 172  * @ack_base:    Base ack address.  If zero then the chip is clear on read.
 173  *
 174  * @num_regs:    Number of registers in each control bank.
 175  * @irqs:        Descriptors for individual IRQs.  Interrupt numbers are
 176  *               assigned based on the index in the array of the interrupt.
 177  * @num_irqs:    Number of descriptors.
 178  */
 179 struct regmap_irq_chip {
 180         const char *name;
 181
 182         unsigned int status_base;
 183         unsigned int mask_base;
 184         unsigned int ack_base;
 185
 186         int num_regs;
 187
 188         const struct regmap_irq *irqs;
 189         int num_irqs;
 190 };
 191
 192 struct regmap_irq_chip_data;
 193
 194 int regmap_add_irq_chip(struct regmap *map, int irq, int irq_flags,
 195                         int irq_base, struct regmap_irq_chip *chip,
 196                         struct regmap_irq_chip_data **data);
 197 void regmap_del_irq_chip(int irq, struct regmap_irq_chip_data *data);
 198 int regmap_irq_chip_get_base(struct regmap_irq_chip_data *data);
 199
 200 #endif