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/device.h>
  17 #include <linux/list.h>
  18
  19 struct module;
  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  * @reg_bits: Number of bits in a register address, mandatory.
  50  * @pad_bits: Number of bits of padding between register and value.
  51  * @val_bits: Number of bits in a register value, mandatory.
  52  *
  53  * @writeable_reg: Optional callback returning true if the register
  54  *                 can be written to.
  55  * @readable_reg: Optional callback returning true if the register
  56  *                can be read from.
  57  * @volatile_reg: Optional callback returning true if the register
  58  *                value can't be cached.
  59  * @precious_reg: Optional callback returning true if the rgister
  60  *                should not be read outside of a call from the driver
  61  *                (eg, a clear on read interrupt status register).
  62  *
  63  * @max_register: Optional, specifies the maximum valid register index.
  64  * @reg_defaults: Power on reset values for registers (for use with
  65  *                register cache support).
  66  * @num_reg_defaults: Number of elements in reg_defaults.
  67  *
  68  * @read_flag_mask: Mask to be set in the top byte of the register when doing
  69  *                  a read.
  70  * @write_flag_mask: Mask to be set in the top byte of the register when doing
  71  *                   a write. If both read_flag_mask and write_flag_mask are
  72  *                   empty the regmap_bus default masks are used.
  73  *
  74  * @cache_type: The actual cache type.
  75  * @reg_defaults_raw: Power on reset values for registers (for use with
  76  *                    register cache support).
  77  * @num_reg_defaults_raw: Number of elements in reg_defaults_raw.
  78  */
  79 struct regmap_config {
  80         int reg_bits;
  81         int pad_bits;
  82         int val_bits;
  83
  84         bool (*writeable_reg)(struct device *dev, unsigned int reg);
  85         bool (*readable_reg)(struct device *dev, unsigned int reg);
  86         bool (*volatile_reg)(struct device *dev, unsigned int reg);
  87         bool (*precious_reg)(struct device *dev, unsigned int reg);
  88
  89         unsigned int max_register;
  90         const struct reg_default *reg_defaults;
  91         unsigned int num_reg_defaults;
  92         enum regcache_type cache_type;
  93         const void *reg_defaults_raw;
  94         unsigned int num_reg_defaults_raw;
  95
  96         u8 read_flag_mask;
  97         u8 write_flag_mask;
  98 };
  99
 100 typedef int (*regmap_hw_write)(struct device *dev, const void *data,
 101                                size_t count);
 102 typedef int (*regmap_hw_gather_write)(struct device *dev,
 103                                       const void *reg, size_t reg_len,
 104                                       const void *val, size_t val_len);
 105 typedef int (*regmap_hw_read)(struct device *dev,
 106                               const void *reg_buf, size_t reg_size,
 107                               void *val_buf, size_t val_size);
 108
 109 /**
 110  * Description of a hardware bus for the register map infrastructure.
 111  *
 112  * @write: Write operation.
 113  * @gather_write: Write operation with split register/value, return -ENOTSUPP
 114  *                if not implemented  on a given device.
 115  * @read: Read operation.  Data is returned in the buffer used to transmit
 116  *         data.
 117  * @read_flag_mask: Mask to be set in the top byte of the register when doing
 118  *                  a read.
 119  */
 120 struct regmap_bus {
 121         regmap_hw_write write;
 122         regmap_hw_gather_write gather_write;
 123         regmap_hw_read read;
 124         u8 read_flag_mask;
 125 };
 126
 127 struct regmap *regmap_init(struct device *dev,
 128                            const struct regmap_bus *bus,
 129                            const struct regmap_config *config);
 130 struct regmap *regmap_init_i2c(struct i2c_client *i2c,
 131                                const struct regmap_config *config);
 132 struct regmap *regmap_init_spi(struct spi_device *dev,
 133                                const struct regmap_config *config);
 134
 135 void regmap_exit(struct regmap *map);
 136 int regmap_reinit_cache(struct regmap *map,
 137                         const struct regmap_config *config);
 138 int regmap_write(struct regmap *map, unsigned int reg, unsigned int val);
 139 int regmap_raw_write(struct regmap *map, unsigned int reg,
 140                      const void *val, size_t val_len);
 141 int regmap_read(struct regmap *map, unsigned int reg, unsigned int *val);
 142 int regmap_raw_read(struct regmap *map, unsigned int reg,
 143                     void *val, size_t val_len);
 144 int regmap_bulk_read(struct regmap *map, unsigned int reg, void *val,
 145                      size_t val_count);
 146 int regmap_update_bits(struct regmap *map, unsigned int reg,
 147                        unsigned int mask, unsigned int val);
 148 int regmap_update_bits_check(struct regmap *map, unsigned int reg,
 149                              unsigned int mask, unsigned int val,
 150                              bool *change);
 151
 152 int regcache_sync(struct regmap *map);
 153 void regcache_cache_only(struct regmap *map, bool enable);
 154 void regcache_cache_bypass(struct regmap *map, bool enable);
 155 void regcache_mark_dirty(struct regmap *map);
 156
 157 /**
 158  * Description of an IRQ for the generic regmap irq_chip.
 159  *
 160  * @reg_offset: Offset of the status/mask register within the bank
 161  * @mask:       Mask used to flag/control the register.
 162  */
 163 struct regmap_irq {
 164         unsigned int reg_offset;
 165         unsigned int mask;
 166 };
 167
 168 /**
 169  * Description of a generic regmap irq_chip.  This is not intended to
 170  * handle every possible interrupt controller, but it should handle a
 171  * substantial proportion of those that are found in the wild.
 172  *
 173  * @name:        Descriptive name for IRQ controller.
 174  *
 175  * @status_base: Base status register address.
 176  * @mask_base:   Base mask register address.
 177  * @ack_base:    Base ack address.  If zero then the chip is clear on read.
 178  *
 179  * @num_regs:    Number of registers in each control bank.
 180  * @irqs:        Descriptors for individual IRQs.  Interrupt numbers are
 181  *               assigned based on the index in the array of the interrupt.
 182  * @num_irqs:    Number of descriptors.
 183  */
 184 struct regmap_irq_chip {
 185         const char *name;
 186
 187         unsigned int status_base;
 188         unsigned int mask_base;
 189         unsigned int ack_base;
 190
 191         int num_regs;
 192
 193         const struct regmap_irq *irqs;
 194         int num_irqs;
 195 };
 196
 197 struct regmap_irq_chip_data;
 198
 199 int regmap_add_irq_chip(struct regmap *map, int irq, int irq_flags,
 200                         int irq_base, struct regmap_irq_chip *chip,
 201                         struct regmap_irq_chip_data **data);
 202 void regmap_del_irq_chip(int irq, struct regmap_irq_chip_data *data);
 203 int regmap_irq_chip_get_base(struct regmap_irq_chip_data *data);
 204
 205 #else
 206
 207 /*
 208  * These stubs should only ever be called by generic code which has
 209  * regmap based facilities, if they ever get called at runtime
 210  * something is going wrong and something probably needs to select
 211  * REGMAP.
 212  */
 213
 214 static inline int regmap_write(struct regmap *map, unsigned int reg,
 215                                unsigned int val)
 216 {
 217         WARN_ONCE(1, "regmap API is disabled");
 218         return -EINVAL;
 219 }
 220
 221 static inline int regmap_raw_write(struct regmap *map, unsigned int reg,
 222                                    const void *val, size_t val_len)
 223 {
 224         WARN_ONCE(1, "regmap API is disabled");
 225         return -EINVAL;
 226 }
 227
 228 static inline int regmap_bulk_write(struct regmap *map, unsigned int reg,
 229                                     const void *val, size_t val_count)
 230 {
 231         WARN_ONCE(1, "regmap API is disabled");
 232         return -EINVAL;
 233 }
 234
 235 static inline int regmap_read(struct regmap *map, unsigned int reg,
 236                               unsigned int *val)
 237 {
 238         WARN_ONCE(1, "regmap API is disabled");
 239         return -EINVAL;
 240 }
 241
 242 static inline int regmap_raw_read(struct regmap *map, unsigned int reg,
 243                                   void *val, size_t val_len)
 244 {
 245         WARN_ONCE(1, "regmap API is disabled");
 246         return -EINVAL;
 247 }
 248
 249 static inline int regmap_bulk_read(struct regmap *map, unsigned int reg,
 250                                    void *val, size_t val_count)
 251 {
 252         WARN_ONCE(1, "regmap API is disabled");
 253         return -EINVAL;
 254 }
 255
 256 static inline int regmap_update_bits(struct regmap *map, unsigned int reg,
 257                                      unsigned int mask, unsigned int val)
 258 {
 259         WARN_ONCE(1, "regmap API is disabled");
 260         return -EINVAL;
 261 }
 262
 263 static inline int regmap_update_bits_check(struct regmap *map,
 264                                            unsigned int reg,
 265                                            unsigned int mask, unsigned int val,
 266                                            bool *change)
 267 {
 268         WARN_ONCE(1, "regmap API is disabled");
 269         return -EINVAL;
 270 }
 271
 272 static inline int regmap_get_val_bytes(struct regmap *map)
 273 {
 274         WARN_ONCE(1, "regmap API is disabled");
 275         return -EINVAL;
 276 }
 277
 278 static inline int regcache_sync(struct regmap *map)
 279 {
 280         WARN_ONCE(1, "regmap API is disabled");
 281         return -EINVAL;
 282 }
 283
 284 static inline int regcache_sync_region(struct regmap *map, unsigned int min,
 285                                        unsigned int max)
 286 {
 287         WARN_ONCE(1, "regmap API is disabled");
 288         return -EINVAL;
 289 }
 290
 291 static inline void regcache_cache_only(struct regmap *map, bool enable)
 292 {
 293         WARN_ONCE(1, "regmap API is disabled");
 294 }
 295
 296 static inline void regcache_cache_bypass(struct regmap *map, bool enable)
 297 {
 298         WARN_ONCE(1, "regmap API is disabled");
 299 }
 300
 301 static inline void regcache_mark_dirty(struct regmap *map)
 302 {
 303         WARN_ONCE(1, "regmap API is disabled");
 304 }
 305
 306 static inline int regmap_register_patch(struct regmap *map,
 307                                         const struct reg_default *regs,
 308                                         int num_regs)
 309 {
 310         WARN_ONCE(1, "regmap API is disabled");
 311         return -EINVAL;
 312 }
 313
 314 #endif
 315
 316 #endif