drivers/base/regmap/regmap.c

   1 /*
   2  * Register map access API
   3  *
   4  * Copyright 2011 Wolfson Microelectronics plc
   5  *
   6  * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11  */
  12
  13 #include <linux/device.h>
  14 #include <linux/slab.h>
  15 #include <linux/export.h>
  16 #include <linux/mutex.h>
  17 #include <linux/err.h>
  18
  19 #define CREATE_TRACE_POINTS
  20 #include <trace/events/regmap.h>
  21
  22 #include "internal.h"
  23
  24 bool regmap_writeable(struct regmap *map, unsigned int reg)
  25 {
  26         if (map->max_register && reg > map->max_register)
  27                 return false;
  28
  29         if (map->writeable_reg)
  30                 return map->writeable_reg(map->dev, reg);
  31
  32         return true;
  33 }
  34
  35 bool regmap_readable(struct regmap *map, unsigned int reg)
  36 {
  37         if (map->max_register && reg > map->max_register)
  38                 return false;
  39
  40         if (map->format.format_write)
  41                 return false;
  42
  43         if (map->readable_reg)
  44                 return map->readable_reg(map->dev, reg);
  45
  46         return true;
  47 }
  48
  49 bool regmap_volatile(struct regmap *map, unsigned int reg)
  50 {
  51         if (!regmap_readable(map, reg))
  52                 return false;
  53
  54         if (map->volatile_reg)
  55                 return map->volatile_reg(map->dev, reg);
  56
  57         return true;
  58 }
  59
  60 bool regmap_precious(struct regmap *map, unsigned int reg)
  61 {
  62         if (!regmap_readable(map, reg))
  63                 return false;
  64
  65         if (map->precious_reg)
  66                 return map->precious_reg(map->dev, reg);
  67
  68         return false;
  69 }
  70
  71 static bool regmap_volatile_range(struct regmap *map, unsigned int reg,
  72         unsigned int num)
  73 {
  74         unsigned int i;
  75
  76         for (i = 0; i < num; i++)
  77                 if (!regmap_volatile(map, reg + i))
  78                         return false;
  79
  80         return true;
  81 }
  82
  83 static void regmap_format_2_6_write(struct regmap *map,
  84                                      unsigned int reg, unsigned int val)
  85 {
  86         u8 *out = map->work_buf;
  87
  88         *out = (reg << 6) | val;
  89 }
  90
  91 static void regmap_format_4_12_write(struct regmap *map,
  92                                      unsigned int reg, unsigned int val)
  93 {
  94         __be16 *out = map->work_buf;
  95         *out = cpu_to_be16((reg << 12) | val);
  96 }
  97
  98 static void regmap_format_7_9_write(struct regmap *map,
  99                                     unsigned int reg, unsigned int val)
 100 {
 101         __be16 *out = map->work_buf;
 102         *out = cpu_to_be16((reg << 9) | val);
 103 }
 104
 105 static void regmap_format_10_14_write(struct regmap *map,
 106                                     unsigned int reg, unsigned int val)
 107 {
 108         u8 *out = map->work_buf;
 109
 110         out[2] = val;
 111         out[1] = (val >> 8) | (reg << 6);
 112         out[0] = reg >> 2;
 113 }
 114
 115 static void regmap_format_8(void *buf, unsigned int val, unsigned int shift)
 116 {
 117         u8 *b = buf;
 118
 119         b[0] = val << shift;
 120 }
 121
 122 static void regmap_format_16_be(void *buf, unsigned int val, unsigned int shift)
 123 {
 124         __be16 *b = buf;
 125
 126         b[0] = cpu_to_be16(val << shift);
 127 }
 128
 129 static void regmap_format_16_native(void *buf, unsigned int val,
 130                                     unsigned int shift)
 131 {
 132         *(u16 *)buf = val << shift;
 133 }
 134
 135 static void regmap_format_24(void *buf, unsigned int val, unsigned int shift)
 136 {
 137         u8 *b = buf;
 138
 139         val <<= shift;
 140
 141         b[0] = val >> 16;
 142         b[1] = val >> 8;
 143         b[2] = val;
 144 }
 145
 146 static void regmap_format_32_be(void *buf, unsigned int val, unsigned int shift)
 147 {
 148         __be32 *b = buf;
 149
 150         b[0] = cpu_to_be32(val << shift);
 151 }
 152
 153 static void regmap_format_32_native(void *buf, unsigned int val,
 154                                     unsigned int shift)
 155 {
 156         *(u32 *)buf = val << shift;
 157 }
 158
 159 static unsigned int regmap_parse_8(void *buf)
 160 {
 161         u8 *b = buf;
 162
 163         return b[0];
 164 }
 165
 166 static unsigned int regmap_parse_16_be(void *buf)
 167 {
 168         __be16 *b = buf;
 169
 170         b[0] = be16_to_cpu(b[0]);
 171
 172         return b[0];
 173 }
 174
 175 static unsigned int regmap_parse_16_native(void *buf)
 176 {
 177         return *(u16 *)buf;
 178 }
 179
 180 static unsigned int regmap_parse_24(void *buf)
 181 {
 182         u8 *b = buf;
 183         unsigned int ret = b[2];
 184         ret |= ((unsigned int)b[1]) << 8;
 185         ret |= ((unsigned int)b[0]) << 16;
 186
 187         return ret;
 188 }
 189
 190 static unsigned int regmap_parse_32_be(void *buf)
 191 {
 192         __be32 *b = buf;
 193
 194         b[0] = be32_to_cpu(b[0]);
 195
 196         return b[0];
 197 }
 198
 199 static unsigned int regmap_parse_32_native(void *buf)
 200 {
 201         return *(u32 *)buf;
 202 }
 203
 204 static void regmap_lock_mutex(struct regmap *map)
 205 {
 206         mutex_lock(&map->mutex);
 207 }
 208
 209 static void regmap_unlock_mutex(struct regmap *map)
 210 {
 211         mutex_unlock(&map->mutex);
 212 }
 213
 214 static void regmap_lock_spinlock(struct regmap *map)
 215 {
 216         spin_lock(&map->spinlock);
 217 }
 218
 219 static void regmap_unlock_spinlock(struct regmap *map)
 220 {
 221         spin_unlock(&map->spinlock);
 222 }
 223
 224 static void dev_get_regmap_release(struct device *dev, void *res)
 225 {
 226         /*
 227          * We don't actually have anything to do here; the goal here
 228          * is not to manage the regmap but to provide a simple way to
 229          * get the regmap back given a struct device.
 230          */
 231 }
 232
 233 /**
 234  * regmap_init(): Initialise register map
 235  *
 236  * @dev: Device that will be interacted with
 237  * @bus: Bus-specific callbacks to use with device
 238  * @bus_context: Data passed to bus-specific callbacks
 239  * @config: Configuration for register map
 240  *
 241  * The return value will be an ERR_PTR() on error or a valid pointer to
 242  * a struct regmap.  This function should generally not be called
 243  * directly, it should be called by bus-specific init functions.
 244  */
 245 struct regmap *regmap_init(struct device *dev,
 246                            const struct regmap_bus *bus,
 247                            void *bus_context,
 248                            const struct regmap_config *config)
 249 {
 250         struct regmap *map, **m;
 251         int ret = -EINVAL;
 252         enum regmap_endian reg_endian, val_endian;
 253
 254         if (!bus || !config)
 255                 goto err;
 256
 257         map = kzalloc(sizeof(*map), GFP_KERNEL);
 258         if (map == NULL) {
 259                 ret = -ENOMEM;
 260                 goto err;
 261         }
 262
 263         if (bus->fast_io) {
 264                 spin_lock_init(&map->spinlock);
 265                 map->lock = regmap_lock_spinlock;
 266                 map->unlock = regmap_unlock_spinlock;
 267         } else {
 268                 mutex_init(&map->mutex);
 269                 map->lock = regmap_lock_mutex;
 270                 map->unlock = regmap_unlock_mutex;
 271         }
 272         map->format.buf_size = (config->reg_bits + config->val_bits) / 8;
 273         map->format.reg_bytes = DIV_ROUND_UP(config->reg_bits, 8);
 274         map->format.pad_bytes = config->pad_bits / 8;
 275         map->format.val_bytes = DIV_ROUND_UP(config->val_bits, 8);
 276         map->format.buf_size += map->format.pad_bytes;
 277         map->reg_shift = config->pad_bits % 8;
 278         if (config->reg_stride)
 279                 map->reg_stride = config->reg_stride;
 280         else
 281                 map->reg_stride = 1;
 282         map->use_single_rw = config->use_single_rw;
 283         map->dev = dev;
 284         map->bus = bus;
 285         map->bus_context = bus_context;
 286         map->max_register = config->max_register;
 287         map->writeable_reg = config->writeable_reg;
 288         map->readable_reg = config->readable_reg;
 289         map->volatile_reg = config->volatile_reg;
 290         map->precious_reg = config->precious_reg;
 291         map->cache_type = config->cache_type;
 292         map->name = config->name;
 293
 294         if (config->read_flag_mask || config->write_flag_mask) {
 295                 map->read_flag_mask = config->read_flag_mask;
 296                 map->write_flag_mask = config->write_flag_mask;
 297         } else {
 298                 map->read_flag_mask = bus->read_flag_mask;
 299         }
 300
 301         reg_endian = config->reg_format_endian;
 302         if (reg_endian == REGMAP_ENDIAN_DEFAULT)
 303                 reg_endian = bus->reg_format_endian_default;
 304         if (reg_endian == REGMAP_ENDIAN_DEFAULT)
 305                 reg_endian = REGMAP_ENDIAN_BIG;
 306
 307         val_endian = config->val_format_endian;
 308         if (val_endian == REGMAP_ENDIAN_DEFAULT)
 309                 val_endian = bus->val_format_endian_default;
 310         if (val_endian == REGMAP_ENDIAN_DEFAULT)
 311                 val_endian = REGMAP_ENDIAN_BIG;
 312
 313         switch (config->reg_bits + map->reg_shift) {
 314         case 2:
 315                 switch (config->val_bits) {
 316                 case 6:
 317                         map->format.format_write = regmap_format_2_6_write;
 318                         break;
 319                 default:
 320                         goto err_map;
 321                 }
 322                 break;
 323
 324         case 4:
 325                 switch (config->val_bits) {
 326                 case 12:
 327                         map->format.format_write = regmap_format_4_12_write;
 328                         break;
 329                 default:
 330                         goto err_map;
 331                 }
 332                 break;
 333
 334         case 7:
 335                 switch (config->val_bits) {
 336                 case 9:
 337                         map->format.format_write = regmap_format_7_9_write;
 338                         break;
 339                 default:
 340                         goto err_map;
 341                 }
 342                 break;
 343
 344         case 10:
 345                 switch (config->val_bits) {
 346                 case 14:
 347                         map->format.format_write = regmap_format_10_14_write;
 348                         break;
 349                 default:
 350                         goto err_map;
 351                 }
 352                 break;
 353
 354         case 8:
 355                 map->format.format_reg = regmap_format_8;
 356                 break;
 357
 358         case 16:
 359                 switch (reg_endian) {
 360                 case REGMAP_ENDIAN_BIG:
 361                         map->format.format_reg = regmap_format_16_be;
 362                         break;
 363                 case REGMAP_ENDIAN_NATIVE:
 364                         map->format.format_reg = regmap_format_16_native;
 365                         break;
 366                 default:
 367                         goto err_map;
 368                 }
 369                 break;
 370
 371         case 32:
 372                 switch (reg_endian) {
 373                 case REGMAP_ENDIAN_BIG:
 374                         map->format.format_reg = regmap_format_32_be;
 375                         break;
 376                 case REGMAP_ENDIAN_NATIVE:
 377                         map->format.format_reg = regmap_format_32_native;
 378                         break;
 379                 default:
 380                         goto err_map;
 381                 }
 382                 break;
 383
 384         default:
 385                 goto err_map;
 386         }
 387
 388         switch (config->val_bits) {
 389         case 8:
 390                 map->format.format_val = regmap_format_8;
 391                 map->format.parse_val = regmap_parse_8;
 392                 break;
 393         case 16:
 394                 switch (val_endian) {
 395                 case REGMAP_ENDIAN_BIG:
 396                         map->format.format_val = regmap_format_16_be;
 397                         map->format.parse_val = regmap_parse_16_be;
 398                         break;
 399                 case REGMAP_ENDIAN_NATIVE:
 400                         map->format.format_val = regmap_format_16_native;
 401                         map->format.parse_val = regmap_parse_16_native;
 402                         break;
 403                 default:
 404                         goto err_map;
 405                 }
 406                 break;
 407         case 24:
 408                 if (val_endian != REGMAP_ENDIAN_BIG)
 409                         goto err_map;
 410                 map->format.format_val = regmap_format_24;
 411                 map->format.parse_val = regmap_parse_24;
 412                 break;
 413         case 32:
 414                 switch (val_endian) {
 415                 case REGMAP_ENDIAN_BIG:
 416                         map->format.format_val = regmap_format_32_be;
 417                         map->format.parse_val = regmap_parse_32_be;
 418                         break;
 419                 case REGMAP_ENDIAN_NATIVE:
 420                         map->format.format_val = regmap_format_32_native;
 421                         map->format.parse_val = regmap_parse_32_native;
 422                         break;
 423                 default:
 424                         goto err_map;
 425                 }
 426                 break;
 427         }
 428
 429         if (map->format.format_write) {
 430                 if ((reg_endian != REGMAP_ENDIAN_BIG) ||
 431                     (val_endian != REGMAP_ENDIAN_BIG))
 432                         goto err_map;
 433                 map->use_single_rw = true;
 434         }
 435
 436         if (!map->format.format_write &&
 437             !(map->format.format_reg && map->format.format_val))
 438                 goto err_map;
 439
 440         map->work_buf = kzalloc(map->format.buf_size, GFP_KERNEL);
 441         if (map->work_buf == NULL) {
 442                 ret = -ENOMEM;
 443                 goto err_map;
 444         }
 445
 446         regmap_debugfs_init(map, config->name);
 447
 448         ret = regcache_init(map, config);
 449         if (ret < 0)
 450                 goto err_free_workbuf;
 451
 452         /* Add a devres resource for dev_get_regmap() */
 453         m = devres_alloc(dev_get_regmap_release, sizeof(*m), GFP_KERNEL);
 454         if (!m) {
 455                 ret = -ENOMEM;
 456                 goto err_cache;
 457         }
 458         *m = map;
 459         devres_add(dev, m);
 460
 461         return map;
 462
 463 err_cache:
 464         regcache_exit(map);
 465 err_free_workbuf:
 466         kfree(map->work_buf);
 467 err_map:
 468         kfree(map);
 469 err:
 470         return ERR_PTR(ret);
 471 }
 472 EXPORT_SYMBOL_GPL(regmap_init);
 473
 474 static void devm_regmap_release(struct device *dev, void *res)
 475 {
 476         regmap_exit(*(struct regmap **)res);
 477 }
 478
 479 /**
 480  * devm_regmap_init(): Initialise managed register map
 481  *
 482  * @dev: Device that will be interacted with
 483  * @bus: Bus-specific callbacks to use with device
 484  * @bus_context: Data passed to bus-specific callbacks
 485  * @config: Configuration for register map
 486  *
 487  * The return value will be an ERR_PTR() on error or a valid pointer
 488  * to a struct regmap.  This function should generally not be called
 489  * directly, it should be called by bus-specific init functions.  The
 490  * map will be automatically freed by the device management code.
 491  */
 492 struct regmap *devm_regmap_init(struct device *dev,
 493                                 const struct regmap_bus *bus,
 494                                 void *bus_context,
 495                                 const struct regmap_config *config)
 496 {
 497         struct regmap **ptr, *regmap;
 498
 499         ptr = devres_alloc(devm_regmap_release, sizeof(*ptr), GFP_KERNEL);
 500         if (!ptr)
 501                 return ERR_PTR(-ENOMEM);
 502
 503         regmap = regmap_init(dev, bus, bus_context, config);
 504         if (!IS_ERR(regmap)) {
 505                 *ptr = regmap;
 506                 devres_add(dev, ptr);
 507         } else {
 508                 devres_free(ptr);
 509         }
 510
 511         return regmap;
 512 }
 513 EXPORT_SYMBOL_GPL(devm_regmap_init);
 514
 515 /**
 516  * regmap_reinit_cache(): Reinitialise the current register cache
 517  *
 518  * @map: Register map to operate on.
 519  * @config: New configuration.  Only the cache data will be used.
 520  *
 521  * Discard any existing register cache for the map and initialize a
 522  * new cache.  This can be used to restore the cache to defaults or to
 523  * update the cache configuration to reflect runtime discovery of the
 524  * hardware.
 525  */
 526 int regmap_reinit_cache(struct regmap *map, const struct regmap_config *config)
 527 {
 528         int ret;
 529
 530         map->lock(map);
 531
 532         regcache_exit(map);
 533         regmap_debugfs_exit(map);
 534
 535         map->max_register = config->max_register;
 536         map->writeable_reg = config->writeable_reg;
 537         map->readable_reg = config->readable_reg;
 538         map->volatile_reg = config->volatile_reg;
 539         map->precious_reg = config->precious_reg;
 540         map->cache_type = config->cache_type;
 541
 542         regmap_debugfs_init(map, config->name);
 543
 544         map->cache_bypass = false;
 545         map->cache_only = false;
 546
 547         ret = regcache_init(map, config);
 548
 549         map->unlock(map);
 550
 551         return ret;
 552 }
 553
 554 /**
 555  * regmap_exit(): Free a previously allocated register map
 556  */
 557 void regmap_exit(struct regmap *map)
 558 {
 559         regcache_exit(map);
 560         regmap_debugfs_exit(map);
 561         if (map->bus->free_context)
 562                 map->bus->free_context(map->bus_context);
 563         kfree(map->work_buf);
 564         kfree(map);
 565 }
 566 EXPORT_SYMBOL_GPL(regmap_exit);
 567
 568 static int dev_get_regmap_match(struct device *dev, void *res, void *data)
 569 {
 570         struct regmap **r = res;
 571         if (!r || !*r) {
 572                 WARN_ON(!r || !*r);
 573                 return 0;
 574         }
 575
 576         /* If the user didn't specify a name match any */
 577         if (data)
 578                 return (*r)->name == data;
 579         else
 580                 return 1;
 581 }
 582
 583 /**
 584  * dev_get_regmap(): Obtain the regmap (if any) for a device
 585  *
 586  * @dev: Device to retrieve the map for
 587  * @name: Optional name for the register map, usually NULL.
 588  *
 589  * Returns the regmap for the device if one is present, or NULL.  If
 590  * name is specified then it must match the name specified when
 591  * registering the device, if it is NULL then the first regmap found
 592  * will be used.  Devices with multiple register maps are very rare,
 593  * generic code should normally not need to specify a name.
 594  */
 595 struct regmap *dev_get_regmap(struct device *dev, const char *name)
 596 {
 597         struct regmap **r = devres_find(dev, dev_get_regmap_release,
 598                                         dev_get_regmap_match, (void *)name);
 599
 600         if (!r)
 601                 return NULL;
 602         return *r;
 603 }
 604 EXPORT_SYMBOL_GPL(dev_get_regmap);
 605
 606 static int _regmap_raw_write(struct regmap *map, unsigned int reg,
 607                              const void *val, size_t val_len)
 608 {
 609         u8 *u8 = map->work_buf;
 610         void *buf;
 611         int ret = -ENOTSUPP;
 612         size_t len;
 613         int i;
 614
 615         /* Check for unwritable registers before we start */
 616         if (map->writeable_reg)
 617                 for (i = 0; i < val_len / map->format.val_bytes; i++)
 618                         if (!map->writeable_reg(map->dev,
 619                                                 reg + (i * map->reg_stride)))
 620                                 return -EINVAL;
 621
 622         if (!map->cache_bypass && map->format.parse_val) {
 623                 unsigned int ival;
 624                 int val_bytes = map->format.val_bytes;
 625                 for (i = 0; i < val_len / val_bytes; i++) {
 626                         memcpy(map->work_buf, val + (i * val_bytes), val_bytes);
 627                         ival = map->format.parse_val(map->work_buf);
 628                         ret = regcache_write(map, reg + (i * map->reg_stride),
 629                                              ival);
 630                         if (ret) {
 631                                 dev_err(map->dev,
 632                                    "Error in caching of register: %u ret: %d\n",
 633                                         reg + i, ret);
 634                                 return ret;
 635                         }
 636                 }
 637                 if (map->cache_only) {
 638                         map->cache_dirty = true;
 639                         return 0;
 640                 }
 641         }
 642
 643         map->format.format_reg(map->work_buf, reg, map->reg_shift);
 644
 645         u8[0] |= map->write_flag_mask;
 646
 647         trace_regmap_hw_write_start(map->dev, reg,
 648                                     val_len / map->format.val_bytes);
 649
 650         /* If we're doing a single register write we can probably just
 651          * send the work_buf directly, otherwise try to do a gather
 652          * write.
 653          */
 654         if (val == (map->work_buf + map->format.pad_bytes +
 655                     map->format.reg_bytes))
 656                 ret = map->bus->write(map->bus_context, map->work_buf,
 657                                       map->format.reg_bytes +
 658                                       map->format.pad_bytes +
 659                                       val_len);
 660         else if (map->bus->gather_write)
 661                 ret = map->bus->gather_write(map->bus_context, map->work_buf,
 662                                              map->format.reg_bytes +
 663                                              map->format.pad_bytes,
 664                                              val, val_len);
 665
 666         /* If that didn't work fall back on linearising by hand. */
 667         if (ret == -ENOTSUPP) {
 668                 len = map->format.reg_bytes + map->format.pad_bytes + val_len;
 669                 buf = kzalloc(len, GFP_KERNEL);
 670                 if (!buf)
 671                         return -ENOMEM;
 672
 673                 memcpy(buf, map->work_buf, map->format.reg_bytes);
 674                 memcpy(buf + map->format.reg_bytes + map->format.pad_bytes,
 675                        val, val_len);
 676                 ret = map->bus->write(map->bus_context, buf, len);
 677
 678                 kfree(buf);
 679         }
 680
 681         trace_regmap_hw_write_done(map->dev, reg,
 682                                    val_len / map->format.val_bytes);
 683
 684         return ret;
 685 }
 686
 687 int _regmap_write(struct regmap *map, unsigned int reg,
 688                   unsigned int val)
 689 {
 690         int ret;
 691         BUG_ON(!map->format.format_write && !map->format.format_val);
 692
 693         if (!map->cache_bypass && map->format.format_write) {
 694                 ret = regcache_write(map, reg, val);
 695                 if (ret != 0)
 696                         return ret;
 697                 if (map->cache_only) {
 698                         map->cache_dirty = true;
 699                         return 0;
 700                 }
 701         }
 702
 703         trace_regmap_reg_write(map->dev, reg, val);
 704
 705         if (map->format.format_write) {
 706                 map->format.format_write(map, reg, val);
 707
 708                 trace_regmap_hw_write_start(map->dev, reg, 1);
 709
 710                 ret = map->bus->write(map->bus_context, map->work_buf,
 711                                       map->format.buf_size);
 712
 713                 trace_regmap_hw_write_done(map->dev, reg, 1);
 714
 715                 return ret;
 716         } else {
 717                 map->format.format_val(map->work_buf + map->format.reg_bytes
 718                                        + map->format.pad_bytes, val, 0);
 719                 return _regmap_raw_write(map, reg,
 720                                          map->work_buf +
 721                                          map->format.reg_bytes +
 722                                          map->format.pad_bytes,
 723                                          map->format.val_bytes);
 724         }
 725 }
 726
 727 /**
 728  * regmap_write(): Write a value to a single register
 729  *
 730  * @map: Register map to write to
 731  * @reg: Register to write to
 732  * @val: Value to be written
 733  *
 734  * A value of zero will be returned on success, a negative errno will
 735  * be returned in error cases.
 736  */
 737 int regmap_write(struct regmap *map, unsigned int reg, unsigned int val)
 738 {
 739         int ret;
 740
 741         if (reg % map->reg_stride)
 742                 return -EINVAL;
 743
 744         map->lock(map);
 745
 746         ret = _regmap_write(map, reg, val);
 747
 748         map->unlock(map);
 749
 750         return ret;
 751 }
 752 EXPORT_SYMBOL_GPL(regmap_write);
 753
 754 /**
 755  * regmap_raw_write(): Write raw values to one or more registers
 756  *
 757  * @map: Register map to write to
 758  * @reg: Initial register to write to
 759  * @val: Block of data to be written, laid out for direct transmission to the
 760  *       device
 761  * @val_len: Length of data pointed to by val.
 762  *
 763  * This function is intended to be used for things like firmware
 764  * download where a large block of data needs to be transferred to the
 765  * device.  No formatting will be done on the data provided.
 766  *
 767  * A value of zero will be returned on success, a negative errno will
 768  * be returned in error cases.
 769  */
 770 int regmap_raw_write(struct regmap *map, unsigned int reg,
 771                      const void *val, size_t val_len)
 772 {
 773         int ret;
 774
 775         if (val_len % map->format.val_bytes)
 776                 return -EINVAL;
 777         if (reg % map->reg_stride)
 778                 return -EINVAL;
 779
 780         map->lock(map);
 781
 782         ret = _regmap_raw_write(map, reg, val, val_len);
 783
 784         map->unlock(map);
 785
 786         return ret;
 787 }
 788 EXPORT_SYMBOL_GPL(regmap_raw_write);
 789
 790 /*
 791  * regmap_bulk_write(): Write multiple registers to the device
 792  *
 793  * @map: Register map to write to
 794  * @reg: First register to be write from
 795  * @val: Block of data to be written, in native register size for device
 796  * @val_count: Number of registers to write
 797  *
 798  * This function is intended to be used for writing a large block of
 799  * data to be device either in single transfer or multiple transfer.
 800  *
 801  * A value of zero will be returned on success, a negative errno will
 802  * be returned in error cases.
 803  */
 804 int regmap_bulk_write(struct regmap *map, unsigned int reg, const void *val,
 805                      size_t val_count)
 806 {
 807         int ret = 0, i;
 808         size_t val_bytes = map->format.val_bytes;
 809         void *wval;
 810
 811         if (!map->format.parse_val)
 812                 return -EINVAL;
 813         if (reg % map->reg_stride)
 814                 return -EINVAL;
 815
 816         map->lock(map);
 817
 818         /* No formatting is require if val_byte is 1 */
 819         if (val_bytes == 1) {
 820                 wval = (void *)val;
 821         } else {
 822                 wval = kmemdup(val, val_count * val_bytes, GFP_KERNEL);
 823                 if (!wval) {
 824                         ret = -ENOMEM;
 825                         dev_err(map->dev, "Error in memory allocation\n");
 826                         goto out;
 827                 }
 828                 for (i = 0; i < val_count * val_bytes; i += val_bytes)
 829                         map->format.parse_val(wval + i);
 830         }
 831         /*
 832          * Some devices does not support bulk write, for
 833          * them we have a series of single write operations.
 834          */
 835         if (map->use_single_rw) {
 836                 for (i = 0; i < val_count; i++) {
 837                         ret = regmap_raw_write(map,
 838                                                 reg + (i * map->reg_stride),
 839                                                 val + (i * val_bytes),
 840                                                 val_bytes);
 841                         if (ret != 0)
 842                                 return ret;
 843                 }
 844         } else {
 845                 ret = _regmap_raw_write(map, reg, wval, val_bytes * val_count);
 846         }
 847
 848         if (val_bytes != 1)
 849                 kfree(wval);
 850
 851 out:
 852         map->unlock(map);
 853         return ret;
 854 }
 855 EXPORT_SYMBOL_GPL(regmap_bulk_write);
 856
 857 static int _regmap_raw_read(struct regmap *map, unsigned int reg, void *val,
 858                             unsigned int val_len)
 859 {
 860         u8 *u8 = map->work_buf;
 861         int ret;
 862
 863         map->format.format_reg(map->work_buf, reg, map->reg_shift);
 864
 865         /*
 866          * Some buses or devices flag reads by setting the high bits in the
 867          * register addresss; since it's always the high bits for all
 868          * current formats we can do this here rather than in
 869          * formatting.  This may break if we get interesting formats.
 870          */
 871         u8[0] |= map->read_flag_mask;
 872
 873         trace_regmap_hw_read_start(map->dev, reg,
 874                                    val_len / map->format.val_bytes);
 875
 876         ret = map->bus->read(map->bus_context, map->work_buf,
 877                              map->format.reg_bytes + map->format.pad_bytes,
 878                              val, val_len);
 879
 880         trace_regmap_hw_read_done(map->dev, reg,
 881                                   val_len / map->format.val_bytes);
 882
 883         return ret;
 884 }
 885
 886 static int _regmap_read(struct regmap *map, unsigned int reg,
 887                         unsigned int *val)
 888 {
 889         int ret;
 890
 891         if (!map->cache_bypass) {
 892                 ret = regcache_read(map, reg, val);
 893                 if (ret == 0)
 894                         return 0;
 895         }
 896
 897         if (!map->format.parse_val)
 898                 return -EINVAL;
 899
 900         if (map->cache_only)
 901                 return -EBUSY;
 902
 903         ret = _regmap_raw_read(map, reg, map->work_buf, map->format.val_bytes);
 904         if (ret == 0) {
 905                 *val = map->format.parse_val(map->work_buf);
 906                 trace_regmap_reg_read(map->dev, reg, *val);
 907         }
 908
 909         if (ret == 0 && !map->cache_bypass)
 910                 regcache_write(map, reg, *val);
 911
 912         return ret;
 913 }
 914
 915 /**
 916  * regmap_read(): Read a value from a single register
 917  *
 918  * @map: Register map to write to
 919  * @reg: Register to be read from
 920  * @val: Pointer to store read value
 921  *
 922  * A value of zero will be returned on success, a negative errno will
 923  * be returned in error cases.
 924  */
 925 int regmap_read(struct regmap *map, unsigned int reg, unsigned int *val)
 926 {
 927         int ret;
 928
 929         if (reg % map->reg_stride)
 930                 return -EINVAL;
 931
 932         map->lock(map);
 933
 934         ret = _regmap_read(map, reg, val);
 935
 936         map->unlock(map);
 937
 938         return ret;
 939 }
 940 EXPORT_SYMBOL_GPL(regmap_read);
 941
 942 /**
 943  * regmap_raw_read(): Read raw data from the device
 944  *
 945  * @map: Register map to write to
 946  * @reg: First register to be read from
 947  * @val: Pointer to store read value
 948  * @val_len: Size of data to read
 949  *
 950  * A value of zero will be returned on success, a negative errno will
 951  * be returned in error cases.
 952  */
 953 int regmap_raw_read(struct regmap *map, unsigned int reg, void *val,
 954                     size_t val_len)
 955 {
 956         size_t val_bytes = map->format.val_bytes;
 957         size_t val_count = val_len / val_bytes;
 958         unsigned int v;
 959         int ret, i;
 960
 961         if (val_len % map->format.val_bytes)
 962                 return -EINVAL;
 963         if (reg % map->reg_stride)
 964                 return -EINVAL;
 965
 966         map->lock(map);
 967
 968         if (regmap_volatile_range(map, reg, val_count) || map->cache_bypass ||
 969             map->cache_type == REGCACHE_NONE) {
 970                 /* Physical block read if there's no cache involved */
 971                 ret = _regmap_raw_read(map, reg, val, val_len);
 972
 973         } else {
 974                 /* Otherwise go word by word for the cache; should be low
 975                  * cost as we expect to hit the cache.
 976                  */
 977                 for (i = 0; i < val_count; i++) {
 978                         ret = _regmap_read(map, reg + (i * map->reg_stride),
 979                                            &v);
 980                         if (ret != 0)
 981                                 goto out;
 982
 983                         map->format.format_val(val + (i * val_bytes), v, 0);
 984                 }
 985         }
 986
 987  out:
 988         map->unlock(map);
 989
 990         return ret;
 991 }
 992 EXPORT_SYMBOL_GPL(regmap_raw_read);
 993
 994 /**
 995  * regmap_bulk_read(): Read multiple registers from the device
 996  *
 997  * @map: Register map to write to
 998  * @reg: First register to be read from
 999  * @val: Pointer to store read value, in native register size for device
1000  * @val_count: Number of registers to read
1001  *
1002  * A value of zero will be returned on success, a negative errno will
1003  * be returned in error cases.
1004  */
1005 int regmap_bulk_read(struct regmap *map, unsigned int reg, void *val,
1006                      size_t val_count)
1007 {
1008         int ret, i;
1009         size_t val_bytes = map->format.val_bytes;
1010         bool vol = regmap_volatile_range(map, reg, val_count);
1011
1012         if (!map->format.parse_val)
1013                 return -EINVAL;
1014         if (reg % map->reg_stride)
1015                 return -EINVAL;
1016
1017         if (vol || map->cache_type == REGCACHE_NONE) {
1018                 /*
1019                  * Some devices does not support bulk read, for
1020                  * them we have a series of single read operations.
1021                  */
1022                 if (map->use_single_rw) {
1023                         for (i = 0; i < val_count; i++) {
1024                                 ret = regmap_raw_read(map,
1025                                                 reg + (i * map->reg_stride),
1026                                                 val + (i * val_bytes),
1027                                                 val_bytes);
1028                                 if (ret != 0)
1029                                         return ret;
1030                         }
1031                 } else {
1032                         ret = regmap_raw_read(map, reg, val,
1033                                               val_bytes * val_count);
1034                         if (ret != 0)
1035                                 return ret;
1036                 }
1037
1038                 for (i = 0; i < val_count * val_bytes; i += val_bytes)
1039                         map->format.parse_val(val + i);
1040         } else {
1041                 for (i = 0; i < val_count; i++) {
1042                         unsigned int ival;
1043                         ret = regmap_read(map, reg + (i * map->reg_stride),
1044                                           &ival);
1045                         if (ret != 0)
1046                                 return ret;
1047                         memcpy(val + (i * val_bytes), &ival, val_bytes);
1048                 }
1049         }
1050
1051         return 0;
1052 }
1053 EXPORT_SYMBOL_GPL(regmap_bulk_read);
1054
1055 static int _regmap_update_bits(struct regmap *map, unsigned int reg,
1056                                unsigned int mask, unsigned int val,
1057                                bool *change)
1058 {
1059         int ret;
1060         unsigned int tmp, orig;
1061
1062         map->lock(map);
1063
1064         ret = _regmap_read(map, reg, &orig);
1065         if (ret != 0)
1066                 goto out;
1067
1068         tmp = orig & ~mask;
1069         tmp |= val & mask;
1070
1071         if (tmp != orig) {
1072                 ret = _regmap_write(map, reg, tmp);
1073                 *change = true;
1074         } else {
1075                 *change = false;
1076         }
1077
1078 out:
1079         map->unlock(map);
1080
1081         return ret;
1082 }
1083
1084 /**
1085  * regmap_update_bits: Perform a read/modify/write cycle on the register map
1086  *
1087  * @map: Register map to update
1088  * @reg: Register to update
1089  * @mask: Bitmask to change
1090  * @val: New value for bitmask
1091  *
1092  * Returns zero for success, a negative number on error.
1093  */
1094 int regmap_update_bits(struct regmap *map, unsigned int reg,
1095                        unsigned int mask, unsigned int val)
1096 {
1097         bool change;
1098         return _regmap_update_bits(map, reg, mask, val, &change);
1099 }
1100 EXPORT_SYMBOL_GPL(regmap_update_bits);
1101
1102 /**
1103  * regmap_update_bits_check: Perform a read/modify/write cycle on the
1104  *                           register map and report if updated
1105  *
1106  * @map: Register map to update
1107  * @reg: Register to update
1108  * @mask: Bitmask to change
1109  * @val: New value for bitmask
1110  * @change: Boolean indicating if a write was done
1111  *
1112  * Returns zero for success, a negative number on error.
1113  */
1114 int regmap_update_bits_check(struct regmap *map, unsigned int reg,
1115                              unsigned int mask, unsigned int val,
1116                              bool *change)
1117 {
1118         return _regmap_update_bits(map, reg, mask, val, change);
1119 }
1120 EXPORT_SYMBOL_GPL(regmap_update_bits_check);
1121
1122 /**
1123  * regmap_register_patch: Register and apply register updates to be applied
1124  *                        on device initialistion
1125  *
1126  * @map: Register map to apply updates to.
1127  * @regs: Values to update.
1128  * @num_regs: Number of entries in regs.
1129  *
1130  * Register a set of register updates to be applied to the device
1131  * whenever the device registers are synchronised with the cache and
1132  * apply them immediately.  Typically this is used to apply
1133  * corrections to be applied to the device defaults on startup, such
1134  * as the updates some vendors provide to undocumented registers.
1135  */
1136 int regmap_register_patch(struct regmap *map, const struct reg_default *regs,
1137                           int num_regs)
1138 {
1139         int i, ret;
1140         bool bypass;
1141
1142         /* If needed the implementation can be extended to support this */
1143         if (map->patch)
1144                 return -EBUSY;
1145
1146         map->lock(map);
1147
1148         bypass = map->cache_bypass;
1149
1150         map->cache_bypass = true;
1151
1152         /* Write out first; it's useful to apply even if we fail later. */
1153         for (i = 0; i < num_regs; i++) {
1154                 ret = _regmap_write(map, regs[i].reg, regs[i].def);
1155                 if (ret != 0) {
1156                         dev_err(map->dev, "Failed to write %x = %x: %d\n",
1157                                 regs[i].reg, regs[i].def, ret);
1158                         goto out;
1159                 }
1160         }
1161
1162         map->patch = kcalloc(num_regs, sizeof(struct reg_default), GFP_KERNEL);
1163         if (map->patch != NULL) {
1164                 memcpy(map->patch, regs,
1165                        num_regs * sizeof(struct reg_default));
1166                 map->patch_regs = num_regs;
1167         } else {
1168                 ret = -ENOMEM;
1169         }
1170
1171 out:
1172         map->cache_bypass = bypass;
1173
1174         map->unlock(map);
1175
1176         return ret;
1177 }
1178 EXPORT_SYMBOL_GPL(regmap_register_patch);
1179
1180 /*
1181  * regmap_get_val_bytes(): Report the size of a register value
1182  *
1183  * Report the size of a register value, mainly intended to for use by
1184  * generic infrastructure built on top of regmap.
1185  */
1186 int regmap_get_val_bytes(struct regmap *map)
1187 {
1188         if (map->format.format_write)
1189                 return -EINVAL;
1190
1191         return map->format.val_bytes;
1192 }
1193 EXPORT_SYMBOL_GPL(regmap_get_val_bytes);
1194
1195 static int __init regmap_initcall(void)
1196 {
1197         regmap_debugfs_initcall();
1198
1199         return 0;
1200 }
1201 postcore_initcall(regmap_initcall);