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 #include <linux/rbtree.h>
  18
  19 struct module;
  20 struct device;
  21 struct i2c_client;
  22 struct spi_device;
  23 struct regmap;
  24 struct regmap_range_cfg;
  25
  26 /* An enum of all the supported cache types */
  27 enum regcache_type {
  28         REGCACHE_NONE,
  29         REGCACHE_RBTREE,
  30         REGCACHE_COMPRESSED
  31 };
  32
  33 /**
  34  * Default value for a register.  We use an array of structs rather
  35  * than a simple array as many modern devices have very sparse
  36  * register maps.
  37  *
  38  * @reg: Register address.
  39  * @def: Register default value.
  40  */
  41 struct reg_default {
  42         unsigned int reg;
  43         unsigned int def;
  44 };
  45
  46 #ifdef CONFIG_REGMAP
  47
  48 enum regmap_endian {
  49         /* Unspecified -> 0 -> Backwards compatible default */
  50         REGMAP_ENDIAN_DEFAULT = 0,
  51         REGMAP_ENDIAN_BIG,
  52         REGMAP_ENDIAN_LITTLE,
  53         REGMAP_ENDIAN_NATIVE,
  54 };
  55
  56 /**
  57  * Configuration for the register map of a device.
  58  *
  59  * @name: Optional name of the regmap. Useful when a device has multiple
  60  *        register regions.
  61  *
  62  * @reg_bits: Number of bits in a register address, mandatory.
  63  * @reg_stride: The register address stride. Valid register addresses are a
  64  *              multiple of this value. If set to 0, a value of 1 will be
  65  *              used.
  66  * @pad_bits: Number of bits of padding between register and value.
  67  * @val_bits: Number of bits in a register value, mandatory.
  68  *
  69  * @writeable_reg: Optional callback returning true if the register
  70  *                 can be written to.
  71  * @readable_reg: Optional callback returning true if the register
  72  *                can be read from.
  73  * @volatile_reg: Optional callback returning true if the register
  74  *                value can't be cached.
  75  * @precious_reg: Optional callback returning true if the rgister
  76  *                should not be read outside of a call from the driver
  77  *                (eg, a clear on read interrupt status register).
  78  *
  79  * @max_register: Optional, specifies the maximum valid register index.
  80  * @reg_defaults: Power on reset values for registers (for use with
  81  *                register cache support).
  82  * @num_reg_defaults: Number of elements in reg_defaults.
  83  *
  84  * @read_flag_mask: Mask to be set in the top byte of the register when doing
  85  *                  a read.
  86  * @write_flag_mask: Mask to be set in the top byte of the register when doing
  87  *                   a write. If both read_flag_mask and write_flag_mask are
  88  *                   empty the regmap_bus default masks are used.
  89  * @use_single_rw: If set, converts the bulk read and write operations into
  90  *                  a series of single read and write operations. This is useful
  91  *                  for device that does not support bulk read and write.
  92  *
  93  * @cache_type: The actual cache type.
  94  * @reg_defaults_raw: Power on reset values for registers (for use with
  95  *                    register cache support).
  96  * @num_reg_defaults_raw: Number of elements in reg_defaults_raw.
  97  * @reg_format_endian: Endianness for formatted register addresses. If this is
  98  *                     DEFAULT, the @reg_format_endian_default value from the
  99  *                     regmap bus is used.
 100  * @val_format_endian: Endianness for formatted register values. If this is
 101  *                     DEFAULT, the @reg_format_endian_default value from the
 102  *                     regmap bus is used.
 103  *
 104  * @ranges: Array of configuration entries for virtual address ranges.
 105  * @num_ranges: Number of range configuration entries.
 106  */
 107 struct regmap_config {
 108         const char *name;
 109
 110         int reg_bits;
 111         int reg_stride;
 112         int pad_bits;
 113         int val_bits;
 114
 115         bool (*writeable_reg)(struct device *dev, unsigned int reg);
 116         bool (*readable_reg)(struct device *dev, unsigned int reg);
 117         bool (*volatile_reg)(struct device *dev, unsigned int reg);
 118         bool (*precious_reg)(struct device *dev, unsigned int reg);
 119
 120         unsigned int max_register;
 121         const struct reg_default *reg_defaults;
 122         unsigned int num_reg_defaults;
 123         enum regcache_type cache_type;
 124         const void *reg_defaults_raw;
 125         unsigned int num_reg_defaults_raw;
 126
 127         u8 read_flag_mask;
 128         u8 write_flag_mask;
 129
 130         bool use_single_rw;
 131
 132         enum regmap_endian reg_format_endian;
 133         enum regmap_endian val_format_endian;
 134
 135         const struct regmap_range_cfg *ranges;
 136         unsigned int n_ranges;
 137 };
 138
 139 /**
 140  * Configuration for indirectly accessed or paged registers.
 141  * Registers, mapped to this virtual range, are accessed in two steps:
 142  *     1. page selector register update;
 143  *     2. access through data window registers.
 144  *
 145  * @range_min: Address of the lowest register address in virtual range.
 146  * @range_max: Address of the highest register in virtual range.
 147  *
 148  * @page_sel_reg: Register with selector field.
 149  * @page_sel_mask: Bit shift for selector value.
 150  * @page_sel_shift: Bit mask for selector value.
 151  *
 152  * @window_start: Address of first (lowest) register in data window.
 153  * @window_len: Number of registers in data window.
 154  */
 155 struct regmap_range_cfg {
 156         /* Registers of virtual address range */
 157         unsigned int range_min;
 158         unsigned int range_max;
 159
 160         /* Page selector for indirect addressing */
 161         unsigned int selector_reg;
 162         unsigned int selector_mask;
 163         int selector_shift;
 164
 165         /* Data window (per each page) */
 166         unsigned int window_start;
 167         unsigned int window_len;
 168 };
 169
 170 typedef int (*regmap_hw_write)(void *context, const void *data,
 171                                size_t count);
 172 typedef int (*regmap_hw_gather_write)(void *context,
 173                                       const void *reg, size_t reg_len,
 174                                       const void *val, size_t val_len);
 175 typedef int (*regmap_hw_read)(void *context,
 176                               const void *reg_buf, size_t reg_size,
 177                               void *val_buf, size_t val_size);
 178 typedef void (*regmap_hw_free_context)(void *context);
 179
 180 /**
 181  * Description of a hardware bus for the register map infrastructure.
 182  *
 183  * @fast_io: Register IO is fast. Use a spinlock instead of a mutex
 184  *           to perform locking.
 185  * @write: Write operation.
 186  * @gather_write: Write operation with split register/value, return -ENOTSUPP
 187  *                if not implemented  on a given device.
 188  * @read: Read operation.  Data is returned in the buffer used to transmit
 189  *         data.
 190  * @read_flag_mask: Mask to be set in the top byte of the register when doing
 191  *                  a read.
 192  * @reg_format_endian_default: Default endianness for formatted register
 193  *     addresses. Used when the regmap_config specifies DEFAULT. If this is
 194  *     DEFAULT, BIG is assumed.
 195  * @val_format_endian_default: Default endianness for formatted register
 196  *     values. Used when the regmap_config specifies DEFAULT. If this is
 197  *     DEFAULT, BIG is assumed.
 198  */
 199 struct regmap_bus {
 200         bool fast_io;
 201         regmap_hw_write write;
 202         regmap_hw_gather_write gather_write;
 203         regmap_hw_read read;
 204         regmap_hw_free_context free_context;
 205         u8 read_flag_mask;
 206         enum regmap_endian reg_format_endian_default;
 207         enum regmap_endian val_format_endian_default;
 208 };
 209
 210 struct regmap *regmap_init(struct device *dev,
 211                            const struct regmap_bus *bus,
 212                            void *bus_context,
 213                            const struct regmap_config *config);
 214 struct regmap *regmap_init_i2c(struct i2c_client *i2c,
 215                                const struct regmap_config *config);
 216 struct regmap *regmap_init_spi(struct spi_device *dev,
 217                                const struct regmap_config *config);
 218 struct regmap *regmap_init_mmio(struct device *dev,
 219                                 void __iomem *regs,
 220                                 const struct regmap_config *config);
 221
 222 struct regmap *devm_regmap_init(struct device *dev,
 223                                 const struct regmap_bus *bus,
 224                                 void *bus_context,
 225                                 const struct regmap_config *config);
 226 struct regmap *devm_regmap_init_i2c(struct i2c_client *i2c,
 227                                     const struct regmap_config *config);
 228 struct regmap *devm_regmap_init_spi(struct spi_device *dev,
 229                                     const struct regmap_config *config);
 230 struct regmap *devm_regmap_init_mmio(struct device *dev,
 231                                      void __iomem *regs,
 232                                      const struct regmap_config *config);
 233
 234 void regmap_exit(struct regmap *map);
 235 int regmap_reinit_cache(struct regmap *map,
 236                         const struct regmap_config *config);
 237 struct regmap *dev_get_regmap(struct device *dev, const char *name);
 238 int regmap_write(struct regmap *map, unsigned int reg, unsigned int val);
 239 int regmap_raw_write(struct regmap *map, unsigned int reg,
 240                      const void *val, size_t val_len);
 241 int regmap_bulk_write(struct regmap *map, unsigned int reg, const void *val,
 242                         size_t val_count);
 243 int regmap_read(struct regmap *map, unsigned int reg, unsigned int *val);
 244 int regmap_raw_read(struct regmap *map, unsigned int reg,
 245                     void *val, size_t val_len);
 246 int regmap_bulk_read(struct regmap *map, unsigned int reg, void *val,
 247                      size_t val_count);
 248 int regmap_update_bits(struct regmap *map, unsigned int reg,
 249                        unsigned int mask, unsigned int val);
 250 int regmap_update_bits_check(struct regmap *map, unsigned int reg,
 251                              unsigned int mask, unsigned int val,
 252                              bool *change);
 253 int regmap_get_val_bytes(struct regmap *map);
 254
 255 int regcache_sync(struct regmap *map);
 256 int regcache_sync_region(struct regmap *map, unsigned int min,
 257                          unsigned int max);
 258 void regcache_cache_only(struct regmap *map, bool enable);
 259 void regcache_cache_bypass(struct regmap *map, bool enable);
 260 void regcache_mark_dirty(struct regmap *map);
 261
 262 int regmap_register_patch(struct regmap *map, const struct reg_default *regs,
 263                           int num_regs);
 264
 265 /**
 266  * Description of an IRQ for the generic regmap irq_chip.
 267  *
 268  * @reg_offset: Offset of the status/mask register within the bank
 269  * @mask:       Mask used to flag/control the register.
 270  */
 271 struct regmap_irq {
 272         unsigned int reg_offset;
 273         unsigned int mask;
 274 };
 275
 276 /**
 277  * Description of a generic regmap irq_chip.  This is not intended to
 278  * handle every possible interrupt controller, but it should handle a
 279  * substantial proportion of those that are found in the wild.
 280  *
 281  * @name:        Descriptive name for IRQ controller.
 282  *
 283  * @status_base: Base status register address.
 284  * @mask_base:   Base mask register address.
 285  * @ack_base:    Base ack address.  If zero then the chip is clear on read.
 286  * @wake_base:   Base address for wake enables.  If zero unsupported.
 287  * @irq_reg_stride:  Stride to use for chips where registers are not contiguous.
 288  *
 289  * @num_regs:    Number of registers in each control bank.
 290  * @irqs:        Descriptors for individual IRQs.  Interrupt numbers are
 291  *               assigned based on the index in the array of the interrupt.
 292  * @num_irqs:    Number of descriptors.
 293  */
 294 struct regmap_irq_chip {
 295         const char *name;
 296
 297         unsigned int status_base;
 298         unsigned int mask_base;
 299         unsigned int ack_base;
 300         unsigned int wake_base;
 301         unsigned int irq_reg_stride;
 302
 303         int num_regs;
 304
 305         const struct regmap_irq *irqs;
 306         int num_irqs;
 307 };
 308
 309 struct regmap_irq_chip_data;
 310
 311 int regmap_add_irq_chip(struct regmap *map, int irq, int irq_flags,
 312                         int irq_base, const struct regmap_irq_chip *chip,
 313                         struct regmap_irq_chip_data **data);
 314 void regmap_del_irq_chip(int irq, struct regmap_irq_chip_data *data);
 315 int regmap_irq_chip_get_base(struct regmap_irq_chip_data *data);
 316 int regmap_irq_get_virq(struct regmap_irq_chip_data *data, int irq);
 317
 318 #else
 319
 320 /*
 321  * These stubs should only ever be called by generic code which has
 322  * regmap based facilities, if they ever get called at runtime
 323  * something is going wrong and something probably needs to select
 324  * REGMAP.
 325  */
 326
 327 static inline int regmap_write(struct regmap *map, unsigned int reg,
 328                                unsigned int val)
 329 {
 330         WARN_ONCE(1, "regmap API is disabled");
 331         return -EINVAL;
 332 }
 333
 334 static inline int regmap_raw_write(struct regmap *map, unsigned int reg,
 335                                    const void *val, size_t val_len)
 336 {
 337         WARN_ONCE(1, "regmap API is disabled");
 338         return -EINVAL;
 339 }
 340
 341 static inline int regmap_bulk_write(struct regmap *map, unsigned int reg,
 342                                     const void *val, size_t val_count)
 343 {
 344         WARN_ONCE(1, "regmap API is disabled");
 345         return -EINVAL;
 346 }
 347
 348 static inline int regmap_read(struct regmap *map, unsigned int reg,
 349                               unsigned int *val)
 350 {
 351         WARN_ONCE(1, "regmap API is disabled");
 352         return -EINVAL;
 353 }
 354
 355 static inline int regmap_raw_read(struct regmap *map, unsigned int reg,
 356                                   void *val, size_t val_len)
 357 {
 358         WARN_ONCE(1, "regmap API is disabled");
 359         return -EINVAL;
 360 }
 361
 362 static inline int regmap_bulk_read(struct regmap *map, unsigned int reg,
 363                                    void *val, size_t val_count)
 364 {
 365         WARN_ONCE(1, "regmap API is disabled");
 366         return -EINVAL;
 367 }
 368
 369 static inline int regmap_update_bits(struct regmap *map, unsigned int reg,
 370                                      unsigned int mask, unsigned int val)
 371 {
 372         WARN_ONCE(1, "regmap API is disabled");
 373         return -EINVAL;
 374 }
 375
 376 static inline int regmap_update_bits_check(struct regmap *map,
 377                                            unsigned int reg,
 378                                            unsigned int mask, unsigned int val,
 379                                            bool *change)
 380 {
 381         WARN_ONCE(1, "regmap API is disabled");
 382         return -EINVAL;
 383 }
 384
 385 static inline int regmap_get_val_bytes(struct regmap *map)
 386 {
 387         WARN_ONCE(1, "regmap API is disabled");
 388         return -EINVAL;
 389 }
 390
 391 static inline int regcache_sync(struct regmap *map)
 392 {
 393         WARN_ONCE(1, "regmap API is disabled");
 394         return -EINVAL;
 395 }
 396
 397 static inline int regcache_sync_region(struct regmap *map, unsigned int min,
 398                                        unsigned int max)
 399 {
 400         WARN_ONCE(1, "regmap API is disabled");
 401         return -EINVAL;
 402 }
 403
 404 static inline void regcache_cache_only(struct regmap *map, bool enable)
 405 {
 406         WARN_ONCE(1, "regmap API is disabled");
 407 }
 408
 409 static inline void regcache_cache_bypass(struct regmap *map, bool enable)
 410 {
 411         WARN_ONCE(1, "regmap API is disabled");
 412 }
 413
 414 static inline void regcache_mark_dirty(struct regmap *map)
 415 {
 416         WARN_ONCE(1, "regmap API is disabled");
 417 }
 418
 419 static inline int regmap_register_patch(struct regmap *map,
 420                                         const struct reg_default *regs,
 421                                         int num_regs)
 422 {
 423         WARN_ONCE(1, "regmap API is disabled");
 424         return -EINVAL;
 425 }
 426
 427 static inline struct regmap *dev_get_regmap(struct device *dev,
 428                                             const char *name)
 429 {
 430         return NULL;
 431 }
 432
 433 #endif
 434
 435 #endif