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 irq_domain;
  23 struct spi_device;
  24 struct regmap;
  25 struct regmap_range_cfg;
  26
  27 /* An enum of all the supported cache types */
  28 enum regcache_type {
  29         REGCACHE_NONE,
  30         REGCACHE_RBTREE,
  31         REGCACHE_COMPRESSED,
  32         REGCACHE_FLAT,
  33 };
  34
  35 /**
  36  * Default value for a register.  We use an array of structs rather
  37  * than a simple array as many modern devices have very sparse
  38  * register maps.
  39  *
  40  * @reg: Register address.
  41  * @def: Register default value.
  42  */
  43 struct reg_default {
  44         unsigned int reg;
  45         unsigned int def;
  46 };
  47
  48 #ifdef CONFIG_REGMAP
  49
  50 enum regmap_endian {
  51         /* Unspecified -> 0 -> Backwards compatible default */
  52         REGMAP_ENDIAN_DEFAULT = 0,
  53         REGMAP_ENDIAN_BIG,
  54         REGMAP_ENDIAN_LITTLE,
  55         REGMAP_ENDIAN_NATIVE,
  56 };
  57
  58 /**
  59  * A register range, used for access related checks
  60  * (readable/writeable/volatile/precious checks)
  61  *
  62  * @range_min: address of first register
  63  * @range_max: address of last register
  64  */
  65 struct regmap_range {
  66         unsigned int range_min;
  67         unsigned int range_max;
  68 };
  69
  70 /*
  71  * A table of ranges including some yes ranges and some no ranges.
  72  * If a register belongs to a no_range, the corresponding check function
  73  * will return false. If a register belongs to a yes range, the corresponding
  74  * check function will return true. "no_ranges" are searched first.
  75  *
  76  * @yes_ranges : pointer to an array of regmap ranges used as "yes ranges"
  77  * @n_yes_ranges: size of the above array
  78  * @no_ranges: pointer to an array of regmap ranges used as "no ranges"
  79  * @n_no_ranges: size of the above array
  80  */
  81 struct regmap_access_table {
  82         const struct regmap_range *yes_ranges;
  83         unsigned int n_yes_ranges;
  84         const struct regmap_range *no_ranges;
  85         unsigned int n_no_ranges;
  86 };
  87
  88 typedef void (*regmap_lock)(void *);
  89 typedef void (*regmap_unlock)(void *);
  90
  91 /**
  92  * Configuration for the register map of a device.
  93  *
  94  * @name: Optional name of the regmap. Useful when a device has multiple
  95  *        register regions.
  96  *
  97  * @reg_bits: Number of bits in a register address, mandatory.
  98  * @reg_stride: The register address stride. Valid register addresses are a
  99  *              multiple of this value. If set to 0, a value of 1 will be
 100  *              used.
 101  * @pad_bits: Number of bits of padding between register and value.
 102  * @val_bits: Number of bits in a register value, mandatory.
 103  *
 104  * @writeable_reg: Optional callback returning true if the register
 105  *                 can be written to. If this field is NULL but wr_table
 106  *                 (see below) is not, the check is performed on such table
 107  *                 (a register is writeable if it belongs to one of the ranges
 108  *                  specified by wr_table).
 109  * @readable_reg: Optional callback returning true if the register
 110  *                can be read from. If this field is NULL but rd_table
 111  *                 (see below) is not, the check is performed on such table
 112  *                 (a register is readable if it belongs to one of the ranges
 113  *                  specified by rd_table).
 114  * @volatile_reg: Optional callback returning true if the register
 115  *                value can't be cached. If this field is NULL but
 116  *                volatile_table (see below) is not, the check is performed on
 117  *                such table (a register is volatile if it belongs to one of
 118  *                the ranges specified by volatile_table).
 119  * @precious_reg: Optional callback returning true if the rgister
 120  *                should not be read outside of a call from the driver
 121  *                (eg, a clear on read interrupt status register). If this
 122  *                field is NULL but precious_table (see below) is not, the
 123  *                check is performed on such table (a register is precious if
 124  *                it belongs to one of the ranges specified by precious_table).
 125  * @lock:         Optional lock callback (overrides regmap's default lock
 126  *                function, based on spinlock or mutex).
 127  * @unlock:       As above for unlocking.
 128  * @lock_arg:     this field is passed as the only argument of lock/unlock
 129  *                functions (ignored in case regular lock/unlock functions
 130  *                are not overridden).
 131  * @reg_read:     Optional callback that if filled will be used to perform
 132  *                all the reads from the registers. Should only be provided for
 133  *                devices whos read operation cannot be represented as a simple read
 134  *                operation on a bus such as SPI, I2C, etc. Most of the devices do
 135  *                not need this.
 136  * @reg_write:    Same as above for writing.
 137  * @fast_io:      Register IO is fast. Use a spinlock instead of a mutex
 138  *                to perform locking. This field is ignored if custom lock/unlock
 139  *                functions are used (see fields lock/unlock of struct regmap_config).
 140  *                This field is a duplicate of a similar file in
 141  *                'struct regmap_bus' and serves exact same purpose.
 142  *                 Use it only for "no-bus" cases.
 143  * @max_register: Optional, specifies the maximum valid register index.
 144  * @wr_table:     Optional, points to a struct regmap_access_table specifying
 145  *                valid ranges for write access.
 146  * @rd_table:     As above, for read access.
 147  * @volatile_table: As above, for volatile registers.
 148  * @precious_table: As above, for precious registers.
 149  * @reg_defaults: Power on reset values for registers (for use with
 150  *                register cache support).
 151  * @num_reg_defaults: Number of elements in reg_defaults.
 152  *
 153  * @read_flag_mask: Mask to be set in the top byte of the register when doing
 154  *                  a read.
 155  * @write_flag_mask: Mask to be set in the top byte of the register when doing
 156  *                   a write. If both read_flag_mask and write_flag_mask are
 157  *                   empty the regmap_bus default masks are used.
 158  * @use_single_rw: If set, converts the bulk read and write operations into
 159  *                  a series of single read and write operations. This is useful
 160  *                  for device that does not support bulk read and write.
 161  *
 162  * @cache_type: The actual cache type.
 163  * @reg_defaults_raw: Power on reset values for registers (for use with
 164  *                    register cache support).
 165  * @num_reg_defaults_raw: Number of elements in reg_defaults_raw.
 166  * @reg_format_endian: Endianness for formatted register addresses. If this is
 167  *                     DEFAULT, the @reg_format_endian_default value from the
 168  *                     regmap bus is used.
 169  * @val_format_endian: Endianness for formatted register values. If this is
 170  *                     DEFAULT, the @reg_format_endian_default value from the
 171  *                     regmap bus is used.
 172  *
 173  * @ranges: Array of configuration entries for virtual address ranges.
 174  * @num_ranges: Number of range configuration entries.
 175  */
 176 struct regmap_config {
 177         const char *name;
 178
 179         int reg_bits;
 180         int reg_stride;
 181         int pad_bits;
 182         int val_bits;
 183
 184         bool (*writeable_reg)(struct device *dev, unsigned int reg);
 185         bool (*readable_reg)(struct device *dev, unsigned int reg);
 186         bool (*volatile_reg)(struct device *dev, unsigned int reg);
 187         bool (*precious_reg)(struct device *dev, unsigned int reg);
 188         regmap_lock lock;
 189         regmap_unlock unlock;
 190         void *lock_arg;
 191
 192         int (*reg_read)(void *context, unsigned int reg, unsigned int *val);
 193         int (*reg_write)(void *context, unsigned int reg, unsigned int val);
 194
 195         bool fast_io;
 196
 197         unsigned int max_register;
 198         const struct regmap_access_table *wr_table;
 199         const struct regmap_access_table *rd_table;
 200         const struct regmap_access_table *volatile_table;
 201         const struct regmap_access_table *precious_table;
 202         const struct reg_default *reg_defaults;
 203         unsigned int num_reg_defaults;
 204         enum regcache_type cache_type;
 205         const void *reg_defaults_raw;
 206         unsigned int num_reg_defaults_raw;
 207
 208         u8 read_flag_mask;
 209         u8 write_flag_mask;
 210
 211         bool use_single_rw;
 212
 213         enum regmap_endian reg_format_endian;
 214         enum regmap_endian val_format_endian;
 215
 216         const struct regmap_range_cfg *ranges;
 217         unsigned int num_ranges;
 218 };
 219
 220 /**
 221  * Configuration for indirectly accessed or paged registers.
 222  * Registers, mapped to this virtual range, are accessed in two steps:
 223  *     1. page selector register update;
 224  *     2. access through data window registers.
 225  *
 226  * @name: Descriptive name for diagnostics
 227  *
 228  * @range_min: Address of the lowest register address in virtual range.
 229  * @range_max: Address of the highest register in virtual range.
 230  *
 231  * @page_sel_reg: Register with selector field.
 232  * @page_sel_mask: Bit shift for selector value.
 233  * @page_sel_shift: Bit mask for selector value.
 234  *
 235  * @window_start: Address of first (lowest) register in data window.
 236  * @window_len: Number of registers in data window.
 237  */
 238 struct regmap_range_cfg {
 239         const char *name;
 240
 241         /* Registers of virtual address range */
 242         unsigned int range_min;
 243         unsigned int range_max;
 244
 245         /* Page selector for indirect addressing */
 246         unsigned int selector_reg;
 247         unsigned int selector_mask;
 248         int selector_shift;
 249
 250         /* Data window (per each page) */
 251         unsigned int window_start;
 252         unsigned int window_len;
 253 };
 254
 255 struct regmap_async;
 256
 257 typedef int (*regmap_hw_write)(void *context, const void *data,
 258                                size_t count);
 259 typedef int (*regmap_hw_gather_write)(void *context,
 260                                       const void *reg, size_t reg_len,
 261                                       const void *val, size_t val_len);
 262 typedef int (*regmap_hw_async_write)(void *context,
 263                                      const void *reg, size_t reg_len,
 264                                      const void *val, size_t val_len,
 265                                      struct regmap_async *async);
 266 typedef int (*regmap_hw_read)(void *context,
 267                               const void *reg_buf, size_t reg_size,
 268                               void *val_buf, size_t val_size);
 269 typedef struct regmap_async *(*regmap_hw_async_alloc)(void);
 270 typedef void (*regmap_hw_free_context)(void *context);
 271
 272 /**
 273  * Description of a hardware bus for the register map infrastructure.
 274  *
 275  * @fast_io: Register IO is fast. Use a spinlock instead of a mutex
 276  *           to perform locking. This field is ignored if custom lock/unlock
 277  *           functions are used (see fields lock/unlock of
 278  *           struct regmap_config).
 279  * @write: Write operation.
 280  * @gather_write: Write operation with split register/value, return -ENOTSUPP
 281  *                if not implemented  on a given device.
 282  * @async_write: Write operation which completes asynchronously, optional and
 283  *               must serialise with respect to non-async I/O.
 284  * @read: Read operation.  Data is returned in the buffer used to transmit
 285  *         data.
 286  * @async_alloc: Allocate a regmap_async() structure.
 287  * @read_flag_mask: Mask to be set in the top byte of the register when doing
 288  *                  a read.
 289  * @reg_format_endian_default: Default endianness for formatted register
 290  *     addresses. Used when the regmap_config specifies DEFAULT. If this is
 291  *     DEFAULT, BIG is assumed.
 292  * @val_format_endian_default: Default endianness for formatted register
 293  *     values. Used when the regmap_config specifies DEFAULT. If this is
 294  *     DEFAULT, BIG is assumed.
 295  * @async_size: Size of struct used for async work.
 296  */
 297 struct regmap_bus {
 298         bool fast_io;
 299         regmap_hw_write write;
 300         regmap_hw_gather_write gather_write;
 301         regmap_hw_async_write async_write;
 302         regmap_hw_read read;
 303         regmap_hw_free_context free_context;
 304         regmap_hw_async_alloc async_alloc;
 305         u8 read_flag_mask;
 306         enum regmap_endian reg_format_endian_default;
 307         enum regmap_endian val_format_endian_default;
 308 };
 309
 310 struct regmap *regmap_init(struct device *dev,
 311                            const struct regmap_bus *bus,
 312                            void *bus_context,
 313                            const struct regmap_config *config);
 314 struct regmap *regmap_init_i2c(struct i2c_client *i2c,
 315                                const struct regmap_config *config);
 316 struct regmap *regmap_init_spi(struct spi_device *dev,
 317                                const struct regmap_config *config);
 318 struct regmap *regmap_init_mmio_clk(struct device *dev, const char *clk_id,
 319                                     void __iomem *regs,
 320                                     const struct regmap_config *config);
 321
 322 struct regmap *devm_regmap_init(struct device *dev,
 323                                 const struct regmap_bus *bus,
 324                                 void *bus_context,
 325                                 const struct regmap_config *config);
 326 struct regmap *devm_regmap_init_i2c(struct i2c_client *i2c,
 327                                     const struct regmap_config *config);
 328 struct regmap *devm_regmap_init_spi(struct spi_device *dev,
 329                                     const struct regmap_config *config);
 330 struct regmap *devm_regmap_init_mmio_clk(struct device *dev, const char *clk_id,
 331                                          void __iomem *regs,
 332                                          const struct regmap_config *config);
 333
 334 /**
 335  * regmap_init_mmio(): Initialise register map
 336  *
 337  * @dev: Device that will be interacted with
 338  * @regs: Pointer to memory-mapped IO region
 339  * @config: Configuration for register map
 340  *
 341  * The return value will be an ERR_PTR() on error or a valid pointer to
 342  * a struct regmap.
 343  */
 344 static inline struct regmap *regmap_init_mmio(struct device *dev,
 345                                         void __iomem *regs,
 346                                         const struct regmap_config *config)
 347 {
 348         return regmap_init_mmio_clk(dev, NULL, regs, config);
 349 }
 350
 351 /**
 352  * devm_regmap_init_mmio(): Initialise managed register map
 353  *
 354  * @dev: Device that will be interacted with
 355  * @regs: Pointer to memory-mapped IO region
 356  * @config: Configuration for register map
 357  *
 358  * The return value will be an ERR_PTR() on error or a valid pointer
 359  * to a struct regmap.  The regmap will be automatically freed by the
 360  * device management code.
 361  */
 362 static inline struct regmap *devm_regmap_init_mmio(struct device *dev,
 363                                         void __iomem *regs,
 364                                         const struct regmap_config *config)
 365 {
 366         return devm_regmap_init_mmio_clk(dev, NULL, regs, config);
 367 }
 368
 369 void regmap_exit(struct regmap *map);
 370 int regmap_reinit_cache(struct regmap *map,
 371                         const struct regmap_config *config);
 372 struct regmap *dev_get_regmap(struct device *dev, const char *name);
 373 int regmap_write(struct regmap *map, unsigned int reg, unsigned int val);
 374 int regmap_raw_write(struct regmap *map, unsigned int reg,
 375                      const void *val, size_t val_len);
 376 int regmap_bulk_write(struct regmap *map, unsigned int reg, const void *val,
 377                         size_t val_count);
 378 int regmap_raw_write_async(struct regmap *map, unsigned int reg,
 379                            const void *val, size_t val_len);
 380 int regmap_read(struct regmap *map, unsigned int reg, unsigned int *val);
 381 int regmap_raw_read(struct regmap *map, unsigned int reg,
 382                     void *val, size_t val_len);
 383 int regmap_bulk_read(struct regmap *map, unsigned int reg, void *val,
 384                      size_t val_count);
 385 int regmap_update_bits(struct regmap *map, unsigned int reg,
 386                        unsigned int mask, unsigned int val);
 387 int regmap_update_bits_check(struct regmap *map, unsigned int reg,
 388                              unsigned int mask, unsigned int val,
 389                              bool *change);
 390 int regmap_get_val_bytes(struct regmap *map);
 391 int regmap_async_complete(struct regmap *map);
 392 bool regmap_can_raw_write(struct regmap *map);
 393
 394 int regcache_sync(struct regmap *map);
 395 int regcache_sync_region(struct regmap *map, unsigned int min,
 396                          unsigned int max);
 397 void regcache_cache_only(struct regmap *map, bool enable);
 398 void regcache_cache_bypass(struct regmap *map, bool enable);
 399 void regcache_mark_dirty(struct regmap *map);
 400
 401 int regmap_register_patch(struct regmap *map, const struct reg_default *regs,
 402                           int num_regs);
 403
 404 static inline bool regmap_reg_in_range(unsigned int reg,
 405                                        const struct regmap_range *range)
 406 {
 407         return reg >= range->range_min && reg <= range->range_max;
 408 }
 409
 410 bool regmap_reg_in_ranges(unsigned int reg,
 411                           const struct regmap_range *ranges,
 412                           unsigned int nranges);
 413
 414 /**
 415  * Description of an IRQ for the generic regmap irq_chip.
 416  *
 417  * @reg_offset: Offset of the status/mask register within the bank
 418  * @mask:       Mask used to flag/control the register.
 419  */
 420 struct regmap_irq {
 421         unsigned int reg_offset;
 422         unsigned int mask;
 423 };
 424
 425 /**
 426  * Description of a generic regmap irq_chip.  This is not intended to
 427  * handle every possible interrupt controller, but it should handle a
 428  * substantial proportion of those that are found in the wild.
 429  *
 430  * @name:        Descriptive name for IRQ controller.
 431  *
 432  * @status_base: Base status register address.
 433  * @mask_base:   Base mask register address.
 434  * @ack_base:    Base ack address.  If zero then the chip is clear on read.
 435  * @wake_base:   Base address for wake enables.  If zero unsupported.
 436  * @irq_reg_stride:  Stride to use for chips where registers are not contiguous.
 437  * @runtime_pm:  Hold a runtime PM lock on the device when accessing it.
 438  *
 439  * @num_regs:    Number of registers in each control bank.
 440  * @irqs:        Descriptors for individual IRQs.  Interrupt numbers are
 441  *               assigned based on the index in the array of the interrupt.
 442  * @num_irqs:    Number of descriptors.
 443  */
 444 struct regmap_irq_chip {
 445         const char *name;
 446
 447         unsigned int status_base;
 448         unsigned int mask_base;
 449         unsigned int ack_base;
 450         unsigned int wake_base;
 451         unsigned int irq_reg_stride;
 452         unsigned int mask_invert;
 453         unsigned int wake_invert;
 454         bool runtime_pm;
 455
 456         int num_regs;
 457
 458         const struct regmap_irq *irqs;
 459         int num_irqs;
 460 };
 461
 462 struct regmap_irq_chip_data;
 463
 464 int regmap_add_irq_chip(struct regmap *map, int irq, int irq_flags,
 465                         int irq_base, const struct regmap_irq_chip *chip,
 466                         struct regmap_irq_chip_data **data);
 467 void regmap_del_irq_chip(int irq, struct regmap_irq_chip_data *data);
 468 int regmap_irq_chip_get_base(struct regmap_irq_chip_data *data);
 469 int regmap_irq_get_virq(struct regmap_irq_chip_data *data, int irq);
 470 struct irq_domain *regmap_irq_get_domain(struct regmap_irq_chip_data *data);
 471
 472 #else
 473
 474 /*
 475  * These stubs should only ever be called by generic code which has
 476  * regmap based facilities, if they ever get called at runtime
 477  * something is going wrong and something probably needs to select
 478  * REGMAP.
 479  */
 480
 481 static inline int regmap_write(struct regmap *map, unsigned int reg,
 482                                unsigned int val)
 483 {
 484         WARN_ONCE(1, "regmap API is disabled");
 485         return -EINVAL;
 486 }
 487
 488 static inline int regmap_raw_write(struct regmap *map, unsigned int reg,
 489                                    const void *val, size_t val_len)
 490 {
 491         WARN_ONCE(1, "regmap API is disabled");
 492         return -EINVAL;
 493 }
 494
 495 static inline int regmap_raw_write_async(struct regmap *map, unsigned int reg,
 496                                          const void *val, size_t val_len)
 497 {
 498         WARN_ONCE(1, "regmap API is disabled");
 499         return -EINVAL;
 500 }
 501
 502 static inline int regmap_bulk_write(struct regmap *map, unsigned int reg,
 503                                     const void *val, size_t val_count)
 504 {
 505         WARN_ONCE(1, "regmap API is disabled");
 506         return -EINVAL;
 507 }
 508
 509 static inline int regmap_read(struct regmap *map, unsigned int reg,
 510                               unsigned int *val)
 511 {
 512         WARN_ONCE(1, "regmap API is disabled");
 513         return -EINVAL;
 514 }
 515
 516 static inline int regmap_raw_read(struct regmap *map, unsigned int reg,
 517                                   void *val, size_t val_len)
 518 {
 519         WARN_ONCE(1, "regmap API is disabled");
 520         return -EINVAL;
 521 }
 522
 523 static inline int regmap_bulk_read(struct regmap *map, unsigned int reg,
 524                                    void *val, size_t val_count)
 525 {
 526         WARN_ONCE(1, "regmap API is disabled");
 527         return -EINVAL;
 528 }
 529
 530 static inline int regmap_update_bits(struct regmap *map, unsigned int reg,
 531                                      unsigned int mask, unsigned int val)
 532 {
 533         WARN_ONCE(1, "regmap API is disabled");
 534         return -EINVAL;
 535 }
 536
 537 static inline int regmap_update_bits_check(struct regmap *map,
 538                                            unsigned int reg,
 539                                            unsigned int mask, unsigned int val,
 540                                            bool *change)
 541 {
 542         WARN_ONCE(1, "regmap API is disabled");
 543         return -EINVAL;
 544 }
 545
 546 static inline int regmap_get_val_bytes(struct regmap *map)
 547 {
 548         WARN_ONCE(1, "regmap API is disabled");
 549         return -EINVAL;
 550 }
 551
 552 static inline int regcache_sync(struct regmap *map)
 553 {
 554         WARN_ONCE(1, "regmap API is disabled");
 555         return -EINVAL;
 556 }
 557
 558 static inline int regcache_sync_region(struct regmap *map, unsigned int min,
 559                                        unsigned int max)
 560 {
 561         WARN_ONCE(1, "regmap API is disabled");
 562         return -EINVAL;
 563 }
 564
 565 static inline void regcache_cache_only(struct regmap *map, bool enable)
 566 {
 567         WARN_ONCE(1, "regmap API is disabled");
 568 }
 569
 570 static inline void regcache_cache_bypass(struct regmap *map, bool enable)
 571 {
 572         WARN_ONCE(1, "regmap API is disabled");
 573 }
 574
 575 static inline void regcache_mark_dirty(struct regmap *map)
 576 {
 577         WARN_ONCE(1, "regmap API is disabled");
 578 }
 579
 580 static inline void regmap_async_complete(struct regmap *map)
 581 {
 582         WARN_ONCE(1, "regmap API is disabled");
 583 }
 584
 585 static inline int regmap_register_patch(struct regmap *map,
 586                                         const struct reg_default *regs,
 587                                         int num_regs)
 588 {
 589         WARN_ONCE(1, "regmap API is disabled");
 590         return -EINVAL;
 591 }
 592
 593 static inline struct regmap *dev_get_regmap(struct device *dev,
 594                                             const char *name)
 595 {
 596         return NULL;
 597 }
 598
 599 #endif
 600
 601 #endif