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