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  * @reg_stride: The register address stride. Valid register addresses are a
  54  *              multiple of this value. If set to 0, a value of 1 will be
  55  *              used.
  56  * @pad_bits: Number of bits of padding between register and value.
  57  * @val_bits: Number of bits in a register value, mandatory.
  58  *
  59  * @writeable_reg: Optional callback returning true if the register
  60  *                 can be written to.
  61  * @readable_reg: Optional callback returning true if the register
  62  *                can be read from.
  63  * @volatile_reg: Optional callback returning true if the register
  64  *                value can't be cached.
  65  * @precious_reg: Optional callback returning true if the rgister
  66  *                should not be read outside of a call from the driver
  67  *                (eg, a clear on read interrupt status register).
  68  *
  69  * @max_register: Optional, specifies the maximum valid register index.
  70  * @reg_defaults: Power on reset values for registers (for use with
  71  *                register cache support).
  72  * @num_reg_defaults: Number of elements in reg_defaults.
  73  *
  74  * @read_flag_mask: Mask to be set in the top byte of the register when doing
  75  *                  a read.
  76  * @write_flag_mask: Mask to be set in the top byte of the register when doing
  77  *                   a write. If both read_flag_mask and write_flag_mask are
  78  *                   empty the regmap_bus default masks are used.
  79  * @use_single_rw: If set, converts the bulk read and write operations into
  80  *                  a series of single read and write operations. This is useful
  81  *                  for device that does not support bulk read and write.
  82  *
  83  * @cache_type: The actual cache type.
  84  * @reg_defaults_raw: Power on reset values for registers (for use with
  85  *                    register cache support).
  86  * @num_reg_defaults_raw: Number of elements in reg_defaults_raw.
  87  */
  88 struct regmap_config {
  89         const char *name;
  90
  91         int reg_bits;
  92         int reg_stride;
  93         int pad_bits;
  94         int val_bits;
  95
  96         bool (*writeable_reg)(struct device *dev, unsigned int reg);
  97         bool (*readable_reg)(struct device *dev, unsigned int reg);
  98         bool (*volatile_reg)(struct device *dev, unsigned int reg);
  99         bool (*precious_reg)(struct device *dev, unsigned int reg);
 100
 101         unsigned int max_register;
 102         const struct reg_default *reg_defaults;
 103         unsigned int num_reg_defaults;
 104         enum regcache_type cache_type;
 105         const void *reg_defaults_raw;
 106         unsigned int num_reg_defaults_raw;
 107
 108         u8 read_flag_mask;
 109         u8 write_flag_mask;
 110
 111         bool use_single_rw;
 112 };
 113
 114 typedef int (*regmap_hw_write)(void *context, const void *data,
 115                                size_t count);
 116 typedef int (*regmap_hw_gather_write)(void *context,
 117                                       const void *reg, size_t reg_len,
 118                                       const void *val, size_t val_len);
 119 typedef int (*regmap_hw_read)(void *context,
 120                               const void *reg_buf, size_t reg_size,
 121                               void *val_buf, size_t val_size);
 122 typedef void (*regmap_hw_free_context)(void *context);
 123
 124 /**
 125  * Description of a hardware bus for the register map infrastructure.
 126  *
 127  * @fast_io: Register IO is fast. Use a spinlock instead of a mutex
 128  *           to perform locking.
 129  * @write: Write operation.
 130  * @gather_write: Write operation with split register/value, return -ENOTSUPP
 131  *                if not implemented  on a given device.
 132  * @read: Read operation.  Data is returned in the buffer used to transmit
 133  *         data.
 134  * @read_flag_mask: Mask to be set in the top byte of the register when doing
 135  *                  a read.
 136  */
 137 struct regmap_bus {
 138         bool fast_io;
 139         regmap_hw_write write;
 140         regmap_hw_gather_write gather_write;
 141         regmap_hw_read read;
 142         regmap_hw_free_context free_context;
 143         u8 read_flag_mask;
 144 };
 145
 146 struct regmap *regmap_init(struct device *dev,
 147                            const struct regmap_bus *bus,
 148                            void *bus_context,
 149                            const struct regmap_config *config);
 150 struct regmap *regmap_init_i2c(struct i2c_client *i2c,
 151                                const struct regmap_config *config);
 152 struct regmap *regmap_init_spi(struct spi_device *dev,
 153                                const struct regmap_config *config);
 154 struct regmap *regmap_init_mmio(struct device *dev,
 155                                 void __iomem *regs,
 156                                 const struct regmap_config *config);
 157
 158 struct regmap *devm_regmap_init(struct device *dev,
 159                                 const struct regmap_bus *bus,
 160                                 void *bus_context,
 161                                 const struct regmap_config *config);
 162 struct regmap *devm_regmap_init_i2c(struct i2c_client *i2c,
 163                                     const struct regmap_config *config);
 164 struct regmap *devm_regmap_init_spi(struct spi_device *dev,
 165                                     const struct regmap_config *config);
 166 struct regmap *devm_regmap_init_mmio(struct device *dev,
 167                                      void __iomem *regs,
 168                                      const struct regmap_config *config);
 169
 170 void regmap_exit(struct regmap *map);
 171 int regmap_reinit_cache(struct regmap *map,
 172                         const struct regmap_config *config);
 173 struct regmap *dev_get_regmap(struct device *dev, const char *name);
 174 int regmap_write(struct regmap *map, unsigned int reg, unsigned int val);
 175 int regmap_raw_write(struct regmap *map, unsigned int reg,
 176                      const void *val, size_t val_len);
 177 int regmap_bulk_write(struct regmap *map, unsigned int reg, const void *val,
 178                         size_t val_count);
 179 int regmap_read(struct regmap *map, unsigned int reg, unsigned int *val);
 180 int regmap_raw_read(struct regmap *map, unsigned int reg,
 181                     void *val, size_t val_len);
 182 int regmap_bulk_read(struct regmap *map, unsigned int reg, void *val,
 183                      size_t val_count);
 184 int regmap_update_bits(struct regmap *map, unsigned int reg,
 185                        unsigned int mask, unsigned int val);
 186 int regmap_update_bits_check(struct regmap *map, unsigned int reg,
 187                              unsigned int mask, unsigned int val,
 188                              bool *change);
 189 int regmap_get_val_bytes(struct regmap *map);
 190
 191 int regcache_sync(struct regmap *map);
 192 int regcache_sync_region(struct regmap *map, unsigned int min,
 193                          unsigned int max);
 194 void regcache_cache_only(struct regmap *map, bool enable);
 195 void regcache_cache_bypass(struct regmap *map, bool enable);
 196 void regcache_mark_dirty(struct regmap *map);
 197
 198 int regmap_register_patch(struct regmap *map, const struct reg_default *regs,
 199                           int num_regs);
 200
 201 /**
 202  * Description of an IRQ for the generic regmap irq_chip.
 203  *
 204  * @reg_offset: Offset of the status/mask register within the bank
 205  * @mask:       Mask used to flag/control the register.
 206  */
 207 struct regmap_irq {
 208         unsigned int reg_offset;
 209         unsigned int mask;
 210 };
 211
 212 /**
 213  * Description of a generic regmap irq_chip.  This is not intended to
 214  * handle every possible interrupt controller, but it should handle a
 215  * substantial proportion of those that are found in the wild.
 216  *
 217  * @name:        Descriptive name for IRQ controller.
 218  *
 219  * @status_base: Base status register address.
 220  * @mask_base:   Base mask register address.
 221  * @ack_base:    Base ack address.  If zero then the chip is clear on read.
 222  * @irq_reg_stride:  Stride to use for chips where registers are not contiguous.
 223  *
 224  * @num_regs:    Number of registers in each control bank.
 225  * @irqs:        Descriptors for individual IRQs.  Interrupt numbers are
 226  *               assigned based on the index in the array of the interrupt.
 227  * @num_irqs:    Number of descriptors.
 228  */
 229 struct regmap_irq_chip {
 230         const char *name;
 231
 232         unsigned int status_base;
 233         unsigned int mask_base;
 234         unsigned int ack_base;
 235         unsigned int irq_reg_stride;
 236
 237         int num_regs;
 238
 239         const struct regmap_irq *irqs;
 240         int num_irqs;
 241 };
 242
 243 struct regmap_irq_chip_data;
 244
 245 int regmap_add_irq_chip(struct regmap *map, int irq, int irq_flags,
 246                         int irq_base, struct regmap_irq_chip *chip,
 247                         struct regmap_irq_chip_data **data);
 248 void regmap_del_irq_chip(int irq, struct regmap_irq_chip_data *data);
 249 int regmap_irq_chip_get_base(struct regmap_irq_chip_data *data);
 250 int regmap_irq_get_virq(struct regmap_irq_chip_data *data, int irq);
 251
 252 #else
 253
 254 /*
 255  * These stubs should only ever be called by generic code which has
 256  * regmap based facilities, if they ever get called at runtime
 257  * something is going wrong and something probably needs to select
 258  * REGMAP.
 259  */
 260
 261 static inline int regmap_write(struct regmap *map, unsigned int reg,
 262                                unsigned int val)
 263 {
 264         WARN_ONCE(1, "regmap API is disabled");
 265         return -EINVAL;
 266 }
 267
 268 static inline int regmap_raw_write(struct regmap *map, unsigned int reg,
 269                                    const void *val, size_t val_len)
 270 {
 271         WARN_ONCE(1, "regmap API is disabled");
 272         return -EINVAL;
 273 }
 274
 275 static inline int regmap_bulk_write(struct regmap *map, unsigned int reg,
 276                                     const void *val, size_t val_count)
 277 {
 278         WARN_ONCE(1, "regmap API is disabled");
 279         return -EINVAL;
 280 }
 281
 282 static inline int regmap_read(struct regmap *map, unsigned int reg,
 283                               unsigned int *val)
 284 {
 285         WARN_ONCE(1, "regmap API is disabled");
 286         return -EINVAL;
 287 }
 288
 289 static inline int regmap_raw_read(struct regmap *map, unsigned int reg,
 290                                   void *val, size_t val_len)
 291 {
 292         WARN_ONCE(1, "regmap API is disabled");
 293         return -EINVAL;
 294 }
 295
 296 static inline int regmap_bulk_read(struct regmap *map, unsigned int reg,
 297                                    void *val, size_t val_count)
 298 {
 299         WARN_ONCE(1, "regmap API is disabled");
 300         return -EINVAL;
 301 }
 302
 303 static inline int regmap_update_bits(struct regmap *map, unsigned int reg,
 304                                      unsigned int mask, unsigned int val)
 305 {
 306         WARN_ONCE(1, "regmap API is disabled");
 307         return -EINVAL;
 308 }
 309
 310 static inline int regmap_update_bits_check(struct regmap *map,
 311                                            unsigned int reg,
 312                                            unsigned int mask, unsigned int val,
 313                                            bool *change)
 314 {
 315         WARN_ONCE(1, "regmap API is disabled");
 316         return -EINVAL;
 317 }
 318
 319 static inline int regmap_get_val_bytes(struct regmap *map)
 320 {
 321         WARN_ONCE(1, "regmap API is disabled");
 322         return -EINVAL;
 323 }
 324
 325 static inline int regcache_sync(struct regmap *map)
 326 {
 327         WARN_ONCE(1, "regmap API is disabled");
 328         return -EINVAL;
 329 }
 330
 331 static inline int regcache_sync_region(struct regmap *map, unsigned int min,
 332                                        unsigned int max)
 333 {
 334         WARN_ONCE(1, "regmap API is disabled");
 335         return -EINVAL;
 336 }
 337
 338 static inline void regcache_cache_only(struct regmap *map, bool enable)
 339 {
 340         WARN_ONCE(1, "regmap API is disabled");
 341 }
 342
 343 static inline void regcache_cache_bypass(struct regmap *map, bool enable)
 344 {
 345         WARN_ONCE(1, "regmap API is disabled");
 346 }
 347
 348 static inline void regcache_mark_dirty(struct regmap *map)
 349 {
 350         WARN_ONCE(1, "regmap API is disabled");
 351 }
 352
 353 static inline int regmap_register_patch(struct regmap *map,
 354                                         const struct reg_default *regs,
 355                                         int num_regs)
 356 {
 357         WARN_ONCE(1, "regmap API is disabled");
 358         return -EINVAL;
 359 }
 360
 361 static inline struct regmap *dev_get_regmap(struct device *dev,
 362                                             const char *name)
 363 {
 364         WARN_ONCE(1, "regmap API is disabled");
 365         return NULL;
 366 }
 367
 368 #endif
 369
 370 #endif