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