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(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_24(void *buf, unsigned int val, unsigned int shift)
 130 {
 131         u8 *b = buf;
 132
 133         val <<= shift;
 134
 135         b[0] = val >> 16;
 136         b[1] = val >> 8;
 137         b[2] = val;
 138 }
 139
 140 static void regmap_format_32(void *buf, unsigned int val, unsigned int shift)
 141 {
 142         __be32 *b = buf;
 143
 144         b[0] = cpu_to_be32(val << shift);
 145 }
 146
 147 static unsigned int regmap_parse_8(void *buf)
 148 {
 149         u8 *b = buf;
 150
 151         return b[0];
 152 }
 153
 154 static unsigned int regmap_parse_16(void *buf)
 155 {
 156         __be16 *b = buf;
 157
 158         b[0] = be16_to_cpu(b[0]);
 159
 160         return b[0];
 161 }
 162
 163 static unsigned int regmap_parse_24(void *buf)
 164 {
 165         u8 *b = buf;
 166         unsigned int ret = b[2];
 167         ret |= ((unsigned int)b[1]) << 8;
 168         ret |= ((unsigned int)b[0]) << 16;
 169
 170         return ret;
 171 }
 172
 173 static unsigned int regmap_parse_32(void *buf)
 174 {
 175         __be32 *b = buf;
 176
 177         b[0] = be32_to_cpu(b[0]);
 178
 179         return b[0];
 180 }
 181
 182 static void regmap_lock_mutex(struct regmap *map)
 183 {
 184         mutex_lock(&map->mutex);
 185 }
 186
 187 static void regmap_unlock_mutex(struct regmap *map)
 188 {
 189         mutex_unlock(&map->mutex);
 190 }
 191
 192 static void regmap_lock_spinlock(struct regmap *map)
 193 {
 194         spin_lock(&map->spinlock);
 195 }
 196
 197 static void regmap_unlock_spinlock(struct regmap *map)
 198 {
 199         spin_unlock(&map->spinlock);
 200 }
 201
 202 static void dev_get_regmap_release(struct device *dev, void *res)
 203 {
 204         /*
 205          * We don't actually have anything to do here; the goal here
 206          * is not to manage the regmap but to provide a simple way to
 207          * get the regmap back given a struct device.
 208          */
 209 }
 210
 211 /**
 212  * regmap_init(): Initialise register map
 213  *
 214  * @dev: Device that will be interacted with
 215  * @bus: Bus-specific callbacks to use with device
 216  * @bus_context: Data passed to bus-specific callbacks
 217  * @config: Configuration for register map
 218  *
 219  * The return value will be an ERR_PTR() on error or a valid pointer to
 220  * a struct regmap.  This function should generally not be called
 221  * directly, it should be called by bus-specific init functions.
 222  */
 223 struct regmap *regmap_init(struct device *dev,
 224                            const struct regmap_bus *bus,
 225                            void *bus_context,
 226                            const struct regmap_config *config)
 227 {
 228         struct regmap *map, **m;
 229         int ret = -EINVAL;
 230
 231         if (!bus || !config)
 232                 goto err;
 233
 234         map = kzalloc(sizeof(*map), GFP_KERNEL);
 235         if (map == NULL) {
 236                 ret = -ENOMEM;
 237                 goto err;
 238         }
 239
 240         if (bus->fast_io) {
 241                 spin_lock_init(&map->spinlock);
 242                 map->lock = regmap_lock_spinlock;
 243                 map->unlock = regmap_unlock_spinlock;
 244         } else {
 245                 mutex_init(&map->mutex);
 246                 map->lock = regmap_lock_mutex;
 247                 map->unlock = regmap_unlock_mutex;
 248         }
 249         map->format.reg_bytes = DIV_ROUND_UP(config->reg_bits, 8);
 250         map->format.pad_bytes = config->pad_bits / 8;
 251         map->format.val_bytes = DIV_ROUND_UP(config->val_bits, 8);
 252         map->format.buf_size = DIV_ROUND_UP(config->reg_bits +
 253                         config->val_bits + config->pad_bits, 8);
 254         map->reg_shift = config->pad_bits % 8;
 255         if (config->reg_stride)
 256                 map->reg_stride = config->reg_stride;
 257         else
 258                 map->reg_stride = 1;
 259         map->use_single_rw = config->use_single_rw;
 260         map->dev = dev;
 261         map->bus = bus;
 262         map->bus_context = bus_context;
 263         map->max_register = config->max_register;
 264         map->writeable_reg = config->writeable_reg;
 265         map->readable_reg = config->readable_reg;
 266         map->volatile_reg = config->volatile_reg;
 267         map->precious_reg = config->precious_reg;
 268         map->cache_type = config->cache_type;
 269         map->name = config->name;
 270
 271         if (config->read_flag_mask || config->write_flag_mask) {
 272                 map->read_flag_mask = config->read_flag_mask;
 273                 map->write_flag_mask = config->write_flag_mask;
 274         } else {
 275                 map->read_flag_mask = bus->read_flag_mask;
 276         }
 277
 278         switch (config->reg_bits + map->reg_shift) {
 279         case 2:
 280                 switch (config->val_bits) {
 281                 case 6:
 282                         map->format.format_write = regmap_format_2_6_write;
 283                         break;
 284                 default:
 285                         goto err_map;
 286                 }
 287                 break;
 288
 289         case 4:
 290                 switch (config->val_bits) {
 291                 case 12:
 292                         map->format.format_write = regmap_format_4_12_write;
 293                         break;
 294                 default:
 295                         goto err_map;
 296                 }
 297                 break;
 298
 299         case 7:
 300                 switch (config->val_bits) {
 301                 case 9:
 302                         map->format.format_write = regmap_format_7_9_write;
 303                         break;
 304                 default:
 305                         goto err_map;
 306                 }
 307                 break;
 308
 309         case 10:
 310                 switch (config->val_bits) {
 311                 case 14:
 312                         map->format.format_write = regmap_format_10_14_write;
 313                         break;
 314                 default:
 315                         goto err_map;
 316                 }
 317                 break;
 318
 319         case 8:
 320                 map->format.format_reg = regmap_format_8;
 321                 break;
 322
 323         case 16:
 324                 map->format.format_reg = regmap_format_16;
 325                 break;
 326
 327         case 32:
 328                 map->format.format_reg = regmap_format_32;
 329                 break;
 330
 331         default:
 332                 goto err_map;
 333         }
 334
 335         switch (config->val_bits) {
 336         case 8:
 337                 map->format.format_val = regmap_format_8;
 338                 map->format.parse_val = regmap_parse_8;
 339                 break;
 340         case 16:
 341                 map->format.format_val = regmap_format_16;
 342                 map->format.parse_val = regmap_parse_16;
 343                 break;
 344         case 24:
 345                 map->format.format_val = regmap_format_24;
 346                 map->format.parse_val = regmap_parse_24;
 347                 break;
 348         case 32:
 349                 map->format.format_val = regmap_format_32;
 350                 map->format.parse_val = regmap_parse_32;
 351                 break;
 352         }
 353
 354         if (map->format.format_write)
 355                 map->use_single_rw = true;
 356
 357         if (!map->format.format_write &&
 358             !(map->format.format_reg && map->format.format_val))
 359                 goto err_map;
 360
 361         map->work_buf = kzalloc(map->format.buf_size, GFP_KERNEL);
 362         if (map->work_buf == NULL) {
 363                 ret = -ENOMEM;
 364                 goto err_map;
 365         }
 366
 367         regmap_debugfs_init(map, config->name);
 368
 369         ret = regcache_init(map, config);
 370         if (ret < 0)
 371                 goto err_debugfs;
 372
 373         /* Add a devres resource for dev_get_regmap() */
 374         m = devres_alloc(dev_get_regmap_release, sizeof(*m), GFP_KERNEL);
 375         if (!m) {
 376                 ret = -ENOMEM;
 377                 goto err_cache;
 378         }
 379         *m = map;
 380         devres_add(dev, m);
 381
 382         return map;
 383
 384 err_cache:
 385         regcache_exit(map);
 386 err_debugfs:
 387         regmap_debugfs_exit(map);
 388         kfree(map->work_buf);
 389 err_map:
 390         kfree(map);
 391 err:
 392         return ERR_PTR(ret);
 393 }
 394 EXPORT_SYMBOL_GPL(regmap_init);
 395
 396 static void devm_regmap_release(struct device *dev, void *res)
 397 {
 398         regmap_exit(*(struct regmap **)res);
 399 }
 400
 401 /**
 402  * devm_regmap_init(): Initialise managed register map
 403  *
 404  * @dev: Device that will be interacted with
 405  * @bus: Bus-specific callbacks to use with device
 406  * @bus_context: Data passed to bus-specific callbacks
 407  * @config: Configuration for register map
 408  *
 409  * The return value will be an ERR_PTR() on error or a valid pointer
 410  * to a struct regmap.  This function should generally not be called
 411  * directly, it should be called by bus-specific init functions.  The
 412  * map will be automatically freed by the device management code.
 413  */
 414 struct regmap *devm_regmap_init(struct device *dev,
 415                                 const struct regmap_bus *bus,
 416                                 void *bus_context,
 417                                 const struct regmap_config *config)
 418 {
 419         struct regmap **ptr, *regmap;
 420
 421         ptr = devres_alloc(devm_regmap_release, sizeof(*ptr), GFP_KERNEL);
 422         if (!ptr)
 423                 return ERR_PTR(-ENOMEM);
 424
 425         regmap = regmap_init(dev, bus, bus_context, config);
 426         if (!IS_ERR(regmap)) {
 427                 *ptr = regmap;
 428                 devres_add(dev, ptr);
 429         } else {
 430                 devres_free(ptr);
 431         }
 432
 433         return regmap;
 434 }
 435 EXPORT_SYMBOL_GPL(devm_regmap_init);
 436
 437 /**
 438  * regmap_reinit_cache(): Reinitialise the current register cache
 439  *
 440  * @map: Register map to operate on.
 441  * @config: New configuration.  Only the cache data will be used.
 442  *
 443  * Discard any existing register cache for the map and initialize a
 444  * new cache.  This can be used to restore the cache to defaults or to
 445  * update the cache configuration to reflect runtime discovery of the
 446  * hardware.
 447  */
 448 int regmap_reinit_cache(struct regmap *map, const struct regmap_config *config)
 449 {
 450         int ret;
 451
 452         map->lock(map);
 453
 454         regcache_exit(map);
 455         regmap_debugfs_exit(map);
 456
 457         map->max_register = config->max_register;
 458         map->writeable_reg = config->writeable_reg;
 459         map->readable_reg = config->readable_reg;
 460         map->volatile_reg = config->volatile_reg;
 461         map->precious_reg = config->precious_reg;
 462         map->cache_type = config->cache_type;
 463
 464         regmap_debugfs_init(map, config->name);
 465
 466         map->cache_bypass = false;
 467         map->cache_only = false;
 468
 469         ret = regcache_init(map, config);
 470
 471         map->unlock(map);
 472
 473         return ret;
 474 }
 475 EXPORT_SYMBOL_GPL(regmap_reinit_cache);
 476
 477 /**
 478  * regmap_exit(): Free a previously allocated register map
 479  */
 480 void regmap_exit(struct regmap *map)
 481 {
 482         regcache_exit(map);
 483         regmap_debugfs_exit(map);
 484         if (map->bus->free_context)
 485                 map->bus->free_context(map->bus_context);
 486         kfree(map->work_buf);
 487         kfree(map);
 488 }
 489 EXPORT_SYMBOL_GPL(regmap_exit);
 490
 491 static int dev_get_regmap_match(struct device *dev, void *res, void *data)
 492 {
 493         struct regmap **r = res;
 494         if (!r || !*r) {
 495                 WARN_ON(!r || !*r);
 496                 return 0;
 497         }
 498
 499         /* If the user didn't specify a name match any */
 500         if (data)
 501                 return (*r)->name == data;
 502         else
 503                 return 1;
 504 }
 505
 506 /**
 507  * dev_get_regmap(): Obtain the regmap (if any) for a device
 508  *
 509  * @dev: Device to retrieve the map for
 510  * @name: Optional name for the register map, usually NULL.
 511  *
 512  * Returns the regmap for the device if one is present, or NULL.  If
 513  * name is specified then it must match the name specified when
 514  * registering the device, if it is NULL then the first regmap found
 515  * will be used.  Devices with multiple register maps are very rare,
 516  * generic code should normally not need to specify a name.
 517  */
 518 struct regmap *dev_get_regmap(struct device *dev, const char *name)
 519 {
 520         struct regmap **r = devres_find(dev, dev_get_regmap_release,
 521                                         dev_get_regmap_match, (void *)name);
 522
 523         if (!r)
 524                 return NULL;
 525         return *r;
 526 }
 527 EXPORT_SYMBOL_GPL(dev_get_regmap);
 528
 529 static int _regmap_raw_write(struct regmap *map, unsigned int reg,
 530                              const void *val, size_t val_len)
 531 {
 532         u8 *u8 = map->work_buf;
 533         void *buf;
 534         int ret = -ENOTSUPP;
 535         size_t len;
 536         int i;
 537
 538         /* Check for unwritable registers before we start */
 539         if (map->writeable_reg)
 540                 for (i = 0; i < val_len / map->format.val_bytes; i++)
 541                         if (!map->writeable_reg(map->dev,
 542                                                 reg + (i * map->reg_stride)))
 543                                 return -EINVAL;
 544
 545         if (!map->cache_bypass && map->format.parse_val) {
 546                 unsigned int ival;
 547                 int val_bytes = map->format.val_bytes;
 548                 for (i = 0; i < val_len / val_bytes; i++) {
 549                         memcpy(map->work_buf, val + (i * val_bytes), val_bytes);
 550                         ival = map->format.parse_val(map->work_buf);
 551                         ret = regcache_write(map, reg + (i * map->reg_stride),
 552                                              ival);
 553                         if (ret) {
 554                                 dev_err(map->dev,
 555                                    "Error in caching of register: %u ret: %d\n",
 556                                         reg + i, ret);
 557                                 return ret;
 558                         }
 559                 }
 560                 if (map->cache_only) {
 561                         map->cache_dirty = true;
 562                         return 0;
 563                 }
 564         }
 565
 566         map->format.format_reg(map->work_buf, reg, map->reg_shift);
 567
 568         u8[0] |= map->write_flag_mask;
 569
 570         trace_regmap_hw_write_start(map->dev, reg,
 571                                     val_len / map->format.val_bytes);
 572
 573         /* If we're doing a single register write we can probably just
 574          * send the work_buf directly, otherwise try to do a gather
 575          * write.
 576          */
 577         if (val == (map->work_buf + map->format.pad_bytes +
 578                     map->format.reg_bytes))
 579                 ret = map->bus->write(map->bus_context, map->work_buf,
 580                                       map->format.reg_bytes +
 581                                       map->format.pad_bytes +
 582                                       val_len);
 583         else if (map->bus->gather_write)
 584                 ret = map->bus->gather_write(map->bus_context, map->work_buf,
 585                                              map->format.reg_bytes +
 586                                              map->format.pad_bytes,
 587                                              val, val_len);
 588
 589         /* If that didn't work fall back on linearising by hand. */
 590         if (ret == -ENOTSUPP) {
 591                 len = map->format.reg_bytes + map->format.pad_bytes + val_len;
 592                 buf = kzalloc(len, GFP_KERNEL);
 593                 if (!buf)
 594                         return -ENOMEM;
 595
 596                 memcpy(buf, map->work_buf, map->format.reg_bytes);
 597                 memcpy(buf + map->format.reg_bytes + map->format.pad_bytes,
 598                        val, val_len);
 599                 ret = map->bus->write(map->bus_context, buf, len);
 600
 601                 kfree(buf);
 602         }
 603
 604         trace_regmap_hw_write_done(map->dev, reg,
 605                                    val_len / map->format.val_bytes);
 606
 607         return ret;
 608 }
 609
 610 int _regmap_write(struct regmap *map, unsigned int reg,
 611                   unsigned int val)
 612 {
 613         int ret;
 614         BUG_ON(!map->format.format_write && !map->format.format_val);
 615
 616         if (!map->cache_bypass && map->format.format_write) {
 617                 ret = regcache_write(map, reg, val);
 618                 if (ret != 0)
 619                         return ret;
 620                 if (map->cache_only) {
 621                         map->cache_dirty = true;
 622                         return 0;
 623                 }
 624         }
 625
 626         trace_regmap_reg_write(map->dev, reg, val);
 627
 628         if (map->format.format_write) {
 629                 map->format.format_write(map, reg, val);
 630
 631                 trace_regmap_hw_write_start(map->dev, reg, 1);
 632
 633                 ret = map->bus->write(map->bus_context, map->work_buf,
 634                                       map->format.buf_size);
 635
 636                 trace_regmap_hw_write_done(map->dev, reg, 1);
 637
 638                 return ret;
 639         } else {
 640                 map->format.format_val(map->work_buf + map->format.reg_bytes
 641                                        + map->format.pad_bytes, val, 0);
 642                 return _regmap_raw_write(map, reg,
 643                                          map->work_buf +
 644                                          map->format.reg_bytes +
 645                                          map->format.pad_bytes,
 646                                          map->format.val_bytes);
 647         }
 648 }
 649
 650 /**
 651  * regmap_write(): Write a value to a single register
 652  *
 653  * @map: Register map to write to
 654  * @reg: Register to write to
 655  * @val: Value to be written
 656  *
 657  * A value of zero will be returned on success, a negative errno will
 658  * be returned in error cases.
 659  */
 660 int regmap_write(struct regmap *map, unsigned int reg, unsigned int val)
 661 {
 662         int ret;
 663
 664         if (reg % map->reg_stride)
 665                 return -EINVAL;
 666
 667         map->lock(map);
 668
 669         ret = _regmap_write(map, reg, val);
 670
 671         map->unlock(map);
 672
 673         return ret;
 674 }
 675 EXPORT_SYMBOL_GPL(regmap_write);
 676
 677 /**
 678  * regmap_raw_write(): Write raw values to one or more registers
 679  *
 680  * @map: Register map to write to
 681  * @reg: Initial register to write to
 682  * @val: Block of data to be written, laid out for direct transmission to the
 683  *       device
 684  * @val_len: Length of data pointed to by val.
 685  *
 686  * This function is intended to be used for things like firmware
 687  * download where a large block of data needs to be transferred to the
 688  * device.  No formatting will be done on the data provided.
 689  *
 690  * A value of zero will be returned on success, a negative errno will
 691  * be returned in error cases.
 692  */
 693 int regmap_raw_write(struct regmap *map, unsigned int reg,
 694                      const void *val, size_t val_len)
 695 {
 696         int ret;
 697
 698         if (val_len % map->format.val_bytes)
 699                 return -EINVAL;
 700         if (reg % map->reg_stride)
 701                 return -EINVAL;
 702
 703         map->lock(map);
 704
 705         ret = _regmap_raw_write(map, reg, val, val_len);
 706
 707         map->unlock(map);
 708
 709         return ret;
 710 }
 711 EXPORT_SYMBOL_GPL(regmap_raw_write);
 712
 713 /*
 714  * regmap_bulk_write(): Write multiple registers to the device
 715  *
 716  * @map: Register map to write to
 717  * @reg: First register to be write from
 718  * @val: Block of data to be written, in native register size for device
 719  * @val_count: Number of registers to write
 720  *
 721  * This function is intended to be used for writing a large block of
 722  * data to be device either in single transfer or multiple transfer.
 723  *
 724  * A value of zero will be returned on success, a negative errno will
 725  * be returned in error cases.
 726  */
 727 int regmap_bulk_write(struct regmap *map, unsigned int reg, const void *val,
 728                      size_t val_count)
 729 {
 730         int ret = 0, i;
 731         size_t val_bytes = map->format.val_bytes;
 732         void *wval;
 733
 734         if (!map->format.parse_val)
 735                 return -EINVAL;
 736         if (reg % map->reg_stride)
 737                 return -EINVAL;
 738
 739         map->lock(map);
 740
 741         /* No formatting is require if val_byte is 1 */
 742         if (val_bytes == 1) {
 743                 wval = (void *)val;
 744         } else {
 745                 wval = kmemdup(val, val_count * val_bytes, GFP_KERNEL);
 746                 if (!wval) {
 747                         ret = -ENOMEM;
 748                         dev_err(map->dev, "Error in memory allocation\n");
 749                         goto out;
 750                 }
 751                 for (i = 0; i < val_count * val_bytes; i += val_bytes)
 752                         map->format.parse_val(wval + i);
 753         }
 754         /*
 755          * Some devices does not support bulk write, for
 756          * them we have a series of single write operations.
 757          */
 758         if (map->use_single_rw) {
 759                 for (i = 0; i < val_count; i++) {
 760                         ret = regmap_raw_write(map,
 761                                                 reg + (i * map->reg_stride),
 762                                                 val + (i * val_bytes),
 763                                                 val_bytes);
 764                         if (ret != 0)
 765                                 return ret;
 766                 }
 767         } else {
 768                 ret = _regmap_raw_write(map, reg, wval, val_bytes * val_count);
 769         }
 770
 771         if (val_bytes != 1)
 772                 kfree(wval);
 773
 774 out:
 775         map->unlock(map);
 776         return ret;
 777 }
 778 EXPORT_SYMBOL_GPL(regmap_bulk_write);
 779
 780 static int _regmap_raw_read(struct regmap *map, unsigned int reg, void *val,
 781                             unsigned int val_len)
 782 {
 783         u8 *u8 = map->work_buf;
 784         int ret;
 785
 786         map->format.format_reg(map->work_buf, reg, map->reg_shift);
 787
 788         /*
 789          * Some buses or devices flag reads by setting the high bits in the
 790          * register addresss; since it's always the high bits for all
 791          * current formats we can do this here rather than in
 792          * formatting.  This may break if we get interesting formats.
 793          */
 794         u8[0] |= map->read_flag_mask;
 795
 796         trace_regmap_hw_read_start(map->dev, reg,
 797                                    val_len / map->format.val_bytes);
 798
 799         ret = map->bus->read(map->bus_context, map->work_buf,
 800                              map->format.reg_bytes + map->format.pad_bytes,
 801                              val, val_len);
 802
 803         trace_regmap_hw_read_done(map->dev, reg,
 804                                   val_len / map->format.val_bytes);
 805
 806         return ret;
 807 }
 808
 809 static int _regmap_read(struct regmap *map, unsigned int reg,
 810                         unsigned int *val)
 811 {
 812         int ret;
 813
 814         if (!map->cache_bypass) {
 815                 ret = regcache_read(map, reg, val);
 816                 if (ret == 0)
 817                         return 0;
 818         }
 819
 820         if (!map->format.parse_val)
 821                 return -EINVAL;
 822
 823         if (map->cache_only)
 824                 return -EBUSY;
 825
 826         ret = _regmap_raw_read(map, reg, map->work_buf, map->format.val_bytes);
 827         if (ret == 0) {
 828                 *val = map->format.parse_val(map->work_buf);
 829                 trace_regmap_reg_read(map->dev, reg, *val);
 830         }
 831
 832         if (ret == 0 && !map->cache_bypass)
 833                 regcache_write(map, reg, *val);
 834
 835         return ret;
 836 }
 837
 838 /**
 839  * regmap_read(): Read a value from a single register
 840  *
 841  * @map: Register map to write to
 842  * @reg: Register to be read from
 843  * @val: Pointer to store read value
 844  *
 845  * A value of zero will be returned on success, a negative errno will
 846  * be returned in error cases.
 847  */
 848 int regmap_read(struct regmap *map, unsigned int reg, unsigned int *val)
 849 {
 850         int ret;
 851
 852         if (reg % map->reg_stride)
 853                 return -EINVAL;
 854
 855         map->lock(map);
 856
 857         ret = _regmap_read(map, reg, val);
 858
 859         map->unlock(map);
 860
 861         return ret;
 862 }
 863 EXPORT_SYMBOL_GPL(regmap_read);
 864
 865 /**
 866  * regmap_raw_read(): Read raw data from the device
 867  *
 868  * @map: Register map to write to
 869  * @reg: First register to be read from
 870  * @val: Pointer to store read value
 871  * @val_len: Size of data to read
 872  *
 873  * A value of zero will be returned on success, a negative errno will
 874  * be returned in error cases.
 875  */
 876 int regmap_raw_read(struct regmap *map, unsigned int reg, void *val,
 877                     size_t val_len)
 878 {
 879         size_t val_bytes = map->format.val_bytes;
 880         size_t val_count = val_len / val_bytes;
 881         unsigned int v;
 882         int ret, i;
 883
 884         if (val_len % map->format.val_bytes)
 885                 return -EINVAL;
 886         if (reg % map->reg_stride)
 887                 return -EINVAL;
 888
 889         map->lock(map);
 890
 891         if (regmap_volatile_range(map, reg, val_count) || map->cache_bypass ||
 892             map->cache_type == REGCACHE_NONE) {
 893                 /* Physical block read if there's no cache involved */
 894                 ret = _regmap_raw_read(map, reg, val, val_len);
 895
 896         } else {
 897                 /* Otherwise go word by word for the cache; should be low
 898                  * cost as we expect to hit the cache.
 899                  */
 900                 for (i = 0; i < val_count; i++) {
 901                         ret = _regmap_read(map, reg + (i * map->reg_stride),
 902                                            &v);
 903                         if (ret != 0)
 904                                 goto out;
 905
 906                         map->format.format_val(val + (i * val_bytes), v, 0);
 907                 }
 908         }
 909
 910  out:
 911         map->unlock(map);
 912
 913         return ret;
 914 }
 915 EXPORT_SYMBOL_GPL(regmap_raw_read);
 916
 917 /**
 918  * regmap_bulk_read(): Read multiple registers from the device
 919  *
 920  * @map: Register map to write to
 921  * @reg: First register to be read from
 922  * @val: Pointer to store read value, in native register size for device
 923  * @val_count: Number of registers to read
 924  *
 925  * A value of zero will be returned on success, a negative errno will
 926  * be returned in error cases.
 927  */
 928 int regmap_bulk_read(struct regmap *map, unsigned int reg, void *val,
 929                      size_t val_count)
 930 {
 931         int ret, i;
 932         size_t val_bytes = map->format.val_bytes;
 933         bool vol = regmap_volatile_range(map, reg, val_count);
 934
 935         if (!map->format.parse_val)
 936                 return -EINVAL;
 937         if (reg % map->reg_stride)
 938                 return -EINVAL;
 939
 940         if (vol || map->cache_type == REGCACHE_NONE) {
 941                 /*
 942                  * Some devices does not support bulk read, for
 943                  * them we have a series of single read operations.
 944                  */
 945                 if (map->use_single_rw) {
 946                         for (i = 0; i < val_count; i++) {
 947                                 ret = regmap_raw_read(map,
 948                                                 reg + (i * map->reg_stride),
 949                                                 val + (i * val_bytes),
 950                                                 val_bytes);
 951                                 if (ret != 0)
 952                                         return ret;
 953                         }
 954                 } else {
 955                         ret = regmap_raw_read(map, reg, val,
 956                                               val_bytes * val_count);
 957                         if (ret != 0)
 958                                 return ret;
 959                 }
 960
 961                 for (i = 0; i < val_count * val_bytes; i += val_bytes)
 962                         map->format.parse_val(val + i);
 963         } else {
 964                 for (i = 0; i < val_count; i++) {
 965                         unsigned int ival;
 966                         ret = regmap_read(map, reg + (i * map->reg_stride),
 967                                           &ival);
 968                         if (ret != 0)
 969                                 return ret;
 970                         memcpy(val + (i * val_bytes), &ival, val_bytes);
 971                 }
 972         }
 973
 974         return 0;
 975 }
 976 EXPORT_SYMBOL_GPL(regmap_bulk_read);
 977
 978 static int _regmap_update_bits(struct regmap *map, unsigned int reg,
 979                                unsigned int mask, unsigned int val,
 980                                bool *change)
 981 {
 982         int ret;
 983         unsigned int tmp, orig;
 984
 985         map->lock(map);
 986
 987         ret = _regmap_read(map, reg, &orig);
 988         if (ret != 0)
 989                 goto out;
 990
 991         tmp = orig & ~mask;
 992         tmp |= val & mask;
 993
 994         if (tmp != orig) {
 995                 ret = _regmap_write(map, reg, tmp);
 996                 *change = true;
 997         } else {
 998                 *change = false;
 999         }
1000
1001 out:
1002         map->unlock(map);
1003
1004         return ret;
1005 }
1006
1007 /**
1008  * regmap_update_bits: Perform a read/modify/write cycle on the register map
1009  *
1010  * @map: Register map to update
1011  * @reg: Register to update
1012  * @mask: Bitmask to change
1013  * @val: New value for bitmask
1014  *
1015  * Returns zero for success, a negative number on error.
1016  */
1017 int regmap_update_bits(struct regmap *map, unsigned int reg,
1018                        unsigned int mask, unsigned int val)
1019 {
1020         bool change;
1021         return _regmap_update_bits(map, reg, mask, val, &change);
1022 }
1023 EXPORT_SYMBOL_GPL(regmap_update_bits);
1024
1025 /**
1026  * regmap_update_bits_check: Perform a read/modify/write cycle on the
1027  *                           register map and report if updated
1028  *
1029  * @map: Register map to update
1030  * @reg: Register to update
1031  * @mask: Bitmask to change
1032  * @val: New value for bitmask
1033  * @change: Boolean indicating if a write was done
1034  *
1035  * Returns zero for success, a negative number on error.
1036  */
1037 int regmap_update_bits_check(struct regmap *map, unsigned int reg,
1038                              unsigned int mask, unsigned int val,
1039                              bool *change)
1040 {
1041         return _regmap_update_bits(map, reg, mask, val, change);
1042 }
1043 EXPORT_SYMBOL_GPL(regmap_update_bits_check);
1044
1045 /**
1046  * regmap_register_patch: Register and apply register updates to be applied
1047  *                        on device initialistion
1048  *
1049  * @map: Register map to apply updates to.
1050  * @regs: Values to update.
1051  * @num_regs: Number of entries in regs.
1052  *
1053  * Register a set of register updates to be applied to the device
1054  * whenever the device registers are synchronised with the cache and
1055  * apply them immediately.  Typically this is used to apply
1056  * corrections to be applied to the device defaults on startup, such
1057  * as the updates some vendors provide to undocumented registers.
1058  */
1059 int regmap_register_patch(struct regmap *map, const struct reg_default *regs,
1060                           int num_regs)
1061 {
1062         int i, ret;
1063         bool bypass;
1064
1065         /* If needed the implementation can be extended to support this */
1066         if (map->patch)
1067                 return -EBUSY;
1068
1069         map->lock(map);
1070
1071         bypass = map->cache_bypass;
1072
1073         map->cache_bypass = true;
1074
1075         /* Write out first; it's useful to apply even if we fail later. */
1076         for (i = 0; i < num_regs; i++) {
1077                 ret = _regmap_write(map, regs[i].reg, regs[i].def);
1078                 if (ret != 0) {
1079                         dev_err(map->dev, "Failed to write %x = %x: %d\n",
1080                                 regs[i].reg, regs[i].def, ret);
1081                         goto out;
1082                 }
1083         }
1084
1085         map->patch = kcalloc(num_regs, sizeof(struct reg_default), GFP_KERNEL);
1086         if (map->patch != NULL) {
1087                 memcpy(map->patch, regs,
1088                        num_regs * sizeof(struct reg_default));
1089                 map->patch_regs = num_regs;
1090         } else {
1091                 ret = -ENOMEM;
1092         }
1093
1094 out:
1095         map->cache_bypass = bypass;
1096
1097         map->unlock(map);
1098
1099         return ret;
1100 }
1101 EXPORT_SYMBOL_GPL(regmap_register_patch);
1102
1103 /*
1104  * regmap_get_val_bytes(): Report the size of a register value
1105  *
1106  * Report the size of a register value, mainly intended to for use by
1107  * generic infrastructure built on top of regmap.
1108  */
1109 int regmap_get_val_bytes(struct regmap *map)
1110 {
1111         if (map->format.format_write)
1112                 return -EINVAL;
1113
1114         return map->format.val_bytes;
1115 }
1116 EXPORT_SYMBOL_GPL(regmap_get_val_bytes);
1117
1118 static int __init regmap_initcall(void)
1119 {
1120         regmap_debugfs_initcall();
1121
1122         return 0;
1123 }
1124 postcore_initcall(regmap_initcall);