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 struct regmap;
  23
  24 /* An enum of all the supported cache types */
  25 enum regcache_type {
  26         REGCACHE_NONE,
  27         REGCACHE_RBTREE,
  28         REGCACHE_COMPRESSED
  29 };
  30
  31 /**
  32  * Default value for a register.  We use an array of structs rather
  33  * than a simple array as many modern devices have very sparse
  34  * register maps.
  35  *
  36  * @reg: Register address.
  37  * @def: Register default value.
  38  */
  39 struct reg_default {
  40         unsigned int reg;
  41         unsigned int def;
  42 };
  43
  44 #ifdef CONFIG_REGMAP
  45
  46 /**
  47  * Configuration for the register map of a device.
  48  *
  49  * @reg_bits: Number of bits in a register address, mandatory.
  50  * @pad_bits: Number of bits of padding between register and value.
  51  * @val_bits: Number of bits in a register value, mandatory.
  52  *
  53  * @writeable_reg: Optional callback returning true if the register
  54  *                 can be written to.
  55  * @readable_reg: Optional callback returning true if the register
  56  *                can be read from.
  57  * @volatile_reg: Optional callback returning true if the register
  58  *                value can't be cached.
  59  * @precious_reg: Optional callback returning true if the rgister
  60  *                should not be read outside of a call from the driver
  61  *                (eg, a clear on read interrupt status register).
  62  *
  63  * @max_register: Optional, specifies the maximum valid register index.
  64  * @reg_defaults: Power on reset values for registers (for use with
  65  *                register cache support).
  66  * @num_reg_defaults: Number of elements in reg_defaults.
  67  *
  68  * @read_flag_mask: Mask to be set in the top byte of the register when doing
  69  *                  a read.
  70  * @write_flag_mask: Mask to be set in the top byte of the register when doing
  71  *                   a write. If both read_flag_mask and write_flag_mask are
  72  *                   empty the regmap_bus default masks are used.
  73  *
  74  * @cache_type: The actual cache type.
  75  * @reg_defaults_raw: Power on reset values for registers (for use with
  76  *                    register cache support).
  77  * @num_reg_defaults_raw: Number of elements in reg_defaults_raw.
  78  */
  79 struct regmap_config {
  80         int reg_bits;
  81         int pad_bits;
  82         int val_bits;
  83
  84         bool (*writeable_reg)(struct device *dev, unsigned int reg);
  85         bool (*readable_reg)(struct device *dev, unsigned int reg);
  86         bool (*volatile_reg)(struct device *dev, unsigned int reg);
  87         bool (*precious_reg)(struct device *dev, unsigned int reg);
  88
  89         unsigned int max_register;
  90         const struct reg_default *reg_defaults;
  91         unsigned int num_reg_defaults;
  92         enum regcache_type cache_type;
  93         const void *reg_defaults_raw;
  94         unsigned int num_reg_defaults_raw;
  95
  96         u8 read_flag_mask;
  97         u8 write_flag_mask;
  98 };
  99
 100 typedef int (*regmap_hw_write)(struct device *dev, const void *data,
 101                                size_t count);
 102 typedef int (*regmap_hw_gather_write)(struct device *dev,
 103                                       const void *reg, size_t reg_len,
 104                                       const void *val, size_t val_len);
 105 typedef int (*regmap_hw_read)(struct device *dev,
 106                               const void *reg_buf, size_t reg_size,
 107                               void *val_buf, size_t val_size);
 108
 109 /**
 110  * Description of a hardware bus for the register map infrastructure.
 111  *
 112  * @write: Write operation.
 113  * @gather_write: Write operation with split register/value, return -ENOTSUPP
 114  *                if not implemented  on a given device.
 115  * @read: Read operation.  Data is returned in the buffer used to transmit
 116  *         data.
 117  * @read_flag_mask: Mask to be set in the top byte of the register when doing
 118  *                  a read.
 119  */
 120 struct regmap_bus {
 121         regmap_hw_write write;
 122         regmap_hw_gather_write gather_write;
 123         regmap_hw_read read;
 124         u8 read_flag_mask;
 125 };
 126
 127 struct regmap *regmap_init(struct device *dev,
 128                            const struct regmap_bus *bus,
 129                            const struct regmap_config *config);
 130 struct regmap *regmap_init_i2c(struct i2c_client *i2c,
 131                                const struct regmap_config *config);
 132 struct regmap *regmap_init_spi(struct spi_device *dev,
 133                                const struct regmap_config *config);
 134
 135 struct regmap *devm_regmap_init(struct device *dev,
 136                                 const struct regmap_bus *bus,
 137                                 const struct regmap_config *config);
 138 struct regmap *devm_regmap_init_i2c(struct i2c_client *i2c,
 139                                     const struct regmap_config *config);
 140 struct regmap *devm_regmap_init_spi(struct spi_device *dev,
 141                                     const struct regmap_config *config);
 142
 143 void regmap_exit(struct regmap *map);
 144 int regmap_reinit_cache(struct regmap *map,
 145                         const struct regmap_config *config);
 146 int regmap_write(struct regmap *map, unsigned int reg, unsigned int val);
 147 int regmap_raw_write(struct regmap *map, unsigned int reg,
 148                      const void *val, size_t val_len);
 149 int regmap_read(struct regmap *map, unsigned int reg, unsigned int *val);
 150 int regmap_raw_read(struct regmap *map, unsigned int reg,
 151                     void *val, size_t val_len);
 152 int regmap_bulk_read(struct regmap *map, unsigned int reg, void *val,
 153                      size_t val_count);
 154 int regmap_update_bits(struct regmap *map, unsigned int reg,
 155                        unsigned int mask, unsigned int val);
 156 int regmap_update_bits_check(struct regmap *map, unsigned int reg,
 157                              unsigned int mask, unsigned int val,
 158                              bool *change);
 159
 160 int regcache_sync(struct regmap *map);
 161 void regcache_cache_only(struct regmap *map, bool enable);
 162 void regcache_cache_bypass(struct regmap *map, bool enable);
 163 void regcache_mark_dirty(struct regmap *map);
 164
 165 /**
 166  * Description of an IRQ for the generic regmap irq_chip.
 167  *
 168  * @reg_offset: Offset of the status/mask register within the bank
 169  * @mask:       Mask used to flag/control the register.
 170  */
 171 struct regmap_irq {
 172         unsigned int reg_offset;
 173         unsigned int mask;
 174 };
 175
 176 /**
 177  * Description of a generic regmap irq_chip.  This is not intended to
 178  * handle every possible interrupt controller, but it should handle a
 179  * substantial proportion of those that are found in the wild.
 180  *
 181  * @name:        Descriptive name for IRQ controller.
 182  *
 183  * @status_base: Base status register address.
 184  * @mask_base:   Base mask register address.
 185  * @ack_base:    Base ack address.  If zero then the chip is clear on read.
 186  *
 187  * @num_regs:    Number of registers in each control bank.
 188  * @irqs:        Descriptors for individual IRQs.  Interrupt numbers are
 189  *               assigned based on the index in the array of the interrupt.
 190  * @num_irqs:    Number of descriptors.
 191  */
 192 struct regmap_irq_chip {
 193         const char *name;
 194
 195         unsigned int status_base;
 196         unsigned int mask_base;
 197         unsigned int ack_base;
 198
 199         int num_regs;
 200
 201         const struct regmap_irq *irqs;
 202         int num_irqs;
 203 };
 204
 205 struct regmap_irq_chip_data;
 206
 207 int regmap_add_irq_chip(struct regmap *map, int irq, int irq_flags,
 208                         int irq_base, struct regmap_irq_chip *chip,
 209                         struct regmap_irq_chip_data **data);
 210 void regmap_del_irq_chip(int irq, struct regmap_irq_chip_data *data);
 211 int regmap_irq_chip_get_base(struct regmap_irq_chip_data *data);
 212
 213 #else
 214
 215 /*
 216  * These stubs should only ever be called by generic code which has
 217  * regmap based facilities, if they ever get called at runtime
 218  * something is going wrong and something probably needs to select
 219  * REGMAP.
 220  */
 221
 222 static inline int regmap_write(struct regmap *map, unsigned int reg,
 223                                unsigned int val)
 224 {
 225         WARN_ONCE(1, "regmap API is disabled");
 226         return -EINVAL;
 227 }
 228
 229 static inline int regmap_raw_write(struct regmap *map, unsigned int reg,
 230                                    const void *val, size_t val_len)
 231 {
 232         WARN_ONCE(1, "regmap API is disabled");
 233         return -EINVAL;
 234 }
 235
 236 static inline int regmap_bulk_write(struct regmap *map, unsigned int reg,
 237                                     const void *val, size_t val_count)
 238 {
 239         WARN_ONCE(1, "regmap API is disabled");
 240         return -EINVAL;
 241 }
 242
 243 static inline int regmap_read(struct regmap *map, unsigned int reg,
 244                               unsigned int *val)
 245 {
 246         WARN_ONCE(1, "regmap API is disabled");
 247         return -EINVAL;
 248 }
 249
 250 static inline int regmap_raw_read(struct regmap *map, unsigned int reg,
 251                                   void *val, size_t val_len)
 252 {
 253         WARN_ONCE(1, "regmap API is disabled");
 254         return -EINVAL;
 255 }
 256
 257 static inline int regmap_bulk_read(struct regmap *map, unsigned int reg,
 258                                    void *val, size_t val_count)
 259 {
 260         WARN_ONCE(1, "regmap API is disabled");
 261         return -EINVAL;
 262 }
 263
 264 static inline int regmap_update_bits(struct regmap *map, unsigned int reg,
 265                                      unsigned int mask, unsigned int val)
 266 {
 267         WARN_ONCE(1, "regmap API is disabled");
 268         return -EINVAL;
 269 }
 270
 271 static inline int regmap_update_bits_check(struct regmap *map,
 272                                            unsigned int reg,
 273                                            unsigned int mask, unsigned int val,
 274                                            bool *change)
 275 {
 276         WARN_ONCE(1, "regmap API is disabled");
 277         return -EINVAL;
 278 }
 279
 280 static inline int regmap_get_val_bytes(struct regmap *map)
 281 {
 282         WARN_ONCE(1, "regmap API is disabled");
 283         return -EINVAL;
 284 }
 285
 286 static inline int regcache_sync(struct regmap *map)
 287 {
 288         WARN_ONCE(1, "regmap API is disabled");
 289         return -EINVAL;
 290 }
 291
 292 static inline int regcache_sync_region(struct regmap *map, unsigned int min,
 293                                        unsigned int max)
 294 {
 295         WARN_ONCE(1, "regmap API is disabled");
 296         return -EINVAL;
 297 }
 298
 299 static inline void regcache_cache_only(struct regmap *map, bool enable)
 300 {
 301         WARN_ONCE(1, "regmap API is disabled");
 302 }
 303
 304 static inline void regcache_cache_bypass(struct regmap *map, bool enable)
 305 {
 306         WARN_ONCE(1, "regmap API is disabled");
 307 }
 308
 309 static inline void regcache_mark_dirty(struct regmap *map)
 310 {
 311         WARN_ONCE(1, "regmap API is disabled");
 312 }
 313
 314 static inline int regmap_register_patch(struct regmap *map,
 315                                         const struct reg_default *regs,
 316                                         int num_regs)
 317 {
 318         WARN_ONCE(1, "regmap API is disabled");
 319         return -EINVAL;
 320 }
 321
 322 #endif
 323
 324 #endif