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/list.h>
  17
  18 struct module;
  19 struct device;
  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  * @name: Optional name of the regmap. Useful when a device has multiple
  50  *        register regions.
  51  *
  52  * @reg_bits: Number of bits in a register address, mandatory.
  53  * @pad_bits: Number of bits of padding between register and value.
  54  * @val_bits: Number of bits in a register value, mandatory.
  55  *
  56  * @writeable_reg: Optional callback returning true if the register
  57  *                 can be written to.
  58  * @readable_reg: Optional callback returning true if the register
  59  *                can be read from.
  60  * @volatile_reg: Optional callback returning true if the register
  61  *                value can't be cached.
  62  * @precious_reg: Optional callback returning true if the rgister
  63  *                should not be read outside of a call from the driver
  64  *                (eg, a clear on read interrupt status register).
  65  *
  66  * @max_register: Optional, specifies the maximum valid register index.
  67  * @reg_defaults: Power on reset values for registers (for use with
  68  *                register cache support).
  69  * @num_reg_defaults: Number of elements in reg_defaults.
  70  *
  71  * @read_flag_mask: Mask to be set in the top byte of the register when doing
  72  *                  a read.
  73  * @write_flag_mask: Mask to be set in the top byte of the register when doing
  74  *                   a write. If both read_flag_mask and write_flag_mask are
  75  *                   empty the regmap_bus default masks are used.
  76  *
  77  * @cache_type: The actual cache type.
  78  * @reg_defaults_raw: Power on reset values for registers (for use with
  79  *                    register cache support).
  80  * @num_reg_defaults_raw: Number of elements in reg_defaults_raw.
  81  */
  82 struct regmap_config {
  83         const char *name;
  84
  85         int reg_bits;
  86         int pad_bits;
  87         int val_bits;
  88
  89         bool (*writeable_reg)(struct device *dev, unsigned int reg);
  90         bool (*readable_reg)(struct device *dev, unsigned int reg);
  91         bool (*volatile_reg)(struct device *dev, unsigned int reg);
  92         bool (*precious_reg)(struct device *dev, unsigned int reg);
  93
  94         unsigned int max_register;
  95         const struct reg_default *reg_defaults;
  96         unsigned int num_reg_defaults;
  97         enum regcache_type cache_type;
  98         const void *reg_defaults_raw;
  99         unsigned int num_reg_defaults_raw;
 100
 101         u8 read_flag_mask;
 102         u8 write_flag_mask;
 103 };
 104
 105 typedef int (*regmap_hw_write)(void *context, const void *data,
 106                                size_t count);
 107 typedef int (*regmap_hw_gather_write)(void *context,
 108                                       const void *reg, size_t reg_len,
 109                                       const void *val, size_t val_len);
 110 typedef int (*regmap_hw_read)(void *context,
 111                               const void *reg_buf, size_t reg_size,
 112                               void *val_buf, size_t val_size);
 113 typedef void (*regmap_hw_free_context)(void *context);
 114
 115 /**
 116  * Description of a hardware bus for the register map infrastructure.
 117  *
 118  * @fast_io: Register IO is fast. Use a spinlock instead of a mutex
 119  *           to perform locking.
 120  * @write: Write operation.
 121  * @gather_write: Write operation with split register/value, return -ENOTSUPP
 122  *                if not implemented  on a given device.
 123  * @read: Read operation.  Data is returned in the buffer used to transmit
 124  *         data.
 125  * @read_flag_mask: Mask to be set in the top byte of the register when doing
 126  *                  a read.
 127  */
 128 struct regmap_bus {
 129         bool fast_io;
 130         regmap_hw_write write;
 131         regmap_hw_gather_write gather_write;
 132         regmap_hw_read read;
 133         regmap_hw_free_context free_context;
 134         u8 read_flag_mask;
 135 };
 136
 137 struct regmap *regmap_init(struct device *dev,
 138                            const struct regmap_bus *bus,
 139                            void *bus_context,
 140                            const struct regmap_config *config);
 141 struct regmap *regmap_init_i2c(struct i2c_client *i2c,
 142                                const struct regmap_config *config);
 143 struct regmap *regmap_init_spi(struct spi_device *dev,
 144                                const struct regmap_config *config);
 145 struct regmap *regmap_init_mmio(struct device *dev,
 146                                 void __iomem *regs,
 147                                 const struct regmap_config *config);
 148
 149 struct regmap *devm_regmap_init(struct device *dev,
 150                                 const struct regmap_bus *bus,
 151                                 void *bus_context,
 152                                 const struct regmap_config *config);
 153 struct regmap *devm_regmap_init_i2c(struct i2c_client *i2c,
 154                                     const struct regmap_config *config);
 155 struct regmap *devm_regmap_init_spi(struct spi_device *dev,
 156                                     const struct regmap_config *config);
 157 struct regmap *devm_regmap_init_mmio(struct device *dev,
 158                                      void __iomem *regs,
 159                                      const struct regmap_config *config);
 160
 161 void regmap_exit(struct regmap *map);
 162 int regmap_reinit_cache(struct regmap *map,
 163                         const struct regmap_config *config);
 164 int regmap_write(struct regmap *map, unsigned int reg, unsigned int val);
 165 int regmap_raw_write(struct regmap *map, unsigned int reg,
 166                      const void *val, size_t val_len);
 167 int regmap_bulk_write(struct regmap *map, unsigned int reg, const void *val,
 168                         size_t val_count);
 169 int regmap_read(struct regmap *map, unsigned int reg, unsigned int *val);
 170 int regmap_raw_read(struct regmap *map, unsigned int reg,
 171                     void *val, size_t val_len);
 172 int regmap_bulk_read(struct regmap *map, unsigned int reg, void *val,
 173                      size_t val_count);
 174 int regmap_update_bits(struct regmap *map, unsigned int reg,
 175                        unsigned int mask, unsigned int val);
 176 int regmap_update_bits_check(struct regmap *map, unsigned int reg,
 177                              unsigned int mask, unsigned int val,
 178                              bool *change);
 179 int regmap_get_val_bytes(struct regmap *map);
 180
 181 int regcache_sync(struct regmap *map);
 182 int regcache_sync_region(struct regmap *map, unsigned int min,
 183                          unsigned int max);
 184 void regcache_cache_only(struct regmap *map, bool enable);
 185 void regcache_cache_bypass(struct regmap *map, bool enable);
 186 void regcache_mark_dirty(struct regmap *map);
 187
 188 int regmap_register_patch(struct regmap *map, const struct reg_default *regs,
 189                           int num_regs);
 190
 191 /**
 192  * Description of an IRQ for the generic regmap irq_chip.
 193  *
 194  * @reg_offset: Offset of the status/mask register within the bank
 195  * @mask:       Mask used to flag/control the register.
 196  */
 197 struct regmap_irq {
 198         unsigned int reg_offset;
 199         unsigned int mask;
 200 };
 201
 202 /**
 203  * Description of a generic regmap irq_chip.  This is not intended to
 204  * handle every possible interrupt controller, but it should handle a
 205  * substantial proportion of those that are found in the wild.
 206  *
 207  * @name:        Descriptive name for IRQ controller.
 208  *
 209  * @status_base: Base status register address.
 210  * @mask_base:   Base mask register address.
 211  * @ack_base:    Base ack address.  If zero then the chip is clear on read.
 212  *
 213  * @num_regs:    Number of registers in each control bank.
 214  * @irqs:        Descriptors for individual IRQs.  Interrupt numbers are
 215  *               assigned based on the index in the array of the interrupt.
 216  * @num_irqs:    Number of descriptors.
 217  */
 218 struct regmap_irq_chip {
 219         const char *name;
 220
 221         unsigned int status_base;
 222         unsigned int mask_base;
 223         unsigned int ack_base;
 224
 225         int num_regs;
 226
 227         const struct regmap_irq *irqs;
 228         int num_irqs;
 229 };
 230
 231 struct regmap_irq_chip_data;
 232
 233 int regmap_add_irq_chip(struct regmap *map, int irq, int irq_flags,
 234                         int irq_base, struct regmap_irq_chip *chip,
 235                         struct regmap_irq_chip_data **data);
 236 void regmap_del_irq_chip(int irq, struct regmap_irq_chip_data *data);
 237 int regmap_irq_chip_get_base(struct regmap_irq_chip_data *data);
 238
 239 #else
 240
 241 /*
 242  * These stubs should only ever be called by generic code which has
 243  * regmap based facilities, if they ever get called at runtime
 244  * something is going wrong and something probably needs to select
 245  * REGMAP.
 246  */
 247
 248 static inline int regmap_write(struct regmap *map, unsigned int reg,
 249                                unsigned int val)
 250 {
 251         WARN_ONCE(1, "regmap API is disabled");
 252         return -EINVAL;
 253 }
 254
 255 static inline int regmap_raw_write(struct regmap *map, unsigned int reg,
 256                                    const void *val, size_t val_len)
 257 {
 258         WARN_ONCE(1, "regmap API is disabled");
 259         return -EINVAL;
 260 }
 261
 262 static inline int regmap_bulk_write(struct regmap *map, unsigned int reg,
 263                                     const void *val, size_t val_count)
 264 {
 265         WARN_ONCE(1, "regmap API is disabled");
 266         return -EINVAL;
 267 }
 268
 269 static inline int regmap_read(struct regmap *map, unsigned int reg,
 270                               unsigned int *val)
 271 {
 272         WARN_ONCE(1, "regmap API is disabled");
 273         return -EINVAL;
 274 }
 275
 276 static inline int regmap_raw_read(struct regmap *map, unsigned int reg,
 277                                   void *val, size_t val_len)
 278 {
 279         WARN_ONCE(1, "regmap API is disabled");
 280         return -EINVAL;
 281 }
 282
 283 static inline int regmap_bulk_read(struct regmap *map, unsigned int reg,
 284                                    void *val, size_t val_count)
 285 {
 286         WARN_ONCE(1, "regmap API is disabled");
 287         return -EINVAL;
 288 }
 289
 290 static inline int regmap_update_bits(struct regmap *map, unsigned int reg,
 291                                      unsigned int mask, unsigned int val)
 292 {
 293         WARN_ONCE(1, "regmap API is disabled");
 294         return -EINVAL;
 295 }
 296
 297 static inline int regmap_update_bits_check(struct regmap *map,
 298                                            unsigned int reg,
 299                                            unsigned int mask, unsigned int val,
 300                                            bool *change)
 301 {
 302         WARN_ONCE(1, "regmap API is disabled");
 303         return -EINVAL;
 304 }
 305
 306 static inline int regmap_get_val_bytes(struct regmap *map)
 307 {
 308         WARN_ONCE(1, "regmap API is disabled");
 309         return -EINVAL;
 310 }
 311
 312 static inline int regcache_sync(struct regmap *map)
 313 {
 314         WARN_ONCE(1, "regmap API is disabled");
 315         return -EINVAL;
 316 }
 317
 318 static inline int regcache_sync_region(struct regmap *map, unsigned int min,
 319                                        unsigned int max)
 320 {
 321         WARN_ONCE(1, "regmap API is disabled");
 322         return -EINVAL;
 323 }
 324
 325 static inline void regcache_cache_only(struct regmap *map, bool enable)
 326 {
 327         WARN_ONCE(1, "regmap API is disabled");
 328 }
 329
 330 static inline void regcache_cache_bypass(struct regmap *map, bool enable)
 331 {
 332         WARN_ONCE(1, "regmap API is disabled");
 333 }
 334
 335 static inline void regcache_mark_dirty(struct regmap *map)
 336 {
 337         WARN_ONCE(1, "regmap API is disabled");
 338 }
 339
 340 static inline int regmap_register_patch(struct regmap *map,
 341                                         const struct reg_default *regs,
 342                                         int num_regs)
 343 {
 344         WARN_ONCE(1, "regmap API is disabled");
 345         return -EINVAL;
 346 }
 347
 348 #endif
 349
 350 #endif