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 #include <linux/rbtree.h>
  19
  20 #define CREATE_TRACE_POINTS
  21 #include <trace/events/regmap.h>
  22
  23 #include "internal.h"
  24
  25 /*
  26  * Sometimes for failures during very early init the trace
  27  * infrastructure isn't available early enough to be used.  For this
  28  * sort of problem defining LOG_DEVICE will add printks for basic
  29  * register I/O on a specific device.
  30  */
  31 #undef LOG_DEVICE
  32
  33 static int _regmap_update_bits(struct regmap *map, unsigned int reg,
  34                                unsigned int mask, unsigned int val,
  35                                bool *change);
  36
  37 bool regmap_writeable(struct regmap *map, unsigned int reg)
  38 {
  39         if (map->max_register && reg > map->max_register)
  40                 return false;
  41
  42         if (map->writeable_reg)
  43                 return map->writeable_reg(map->dev, reg);
  44
  45         return true;
  46 }
  47
  48 bool regmap_readable(struct regmap *map, unsigned int reg)
  49 {
  50         if (map->max_register && reg > map->max_register)
  51                 return false;
  52
  53         if (map->format.format_write)
  54                 return false;
  55
  56         if (map->readable_reg)
  57                 return map->readable_reg(map->dev, reg);
  58
  59         return true;
  60 }
  61
  62 bool regmap_volatile(struct regmap *map, unsigned int reg)
  63 {
  64         if (!regmap_readable(map, reg))
  65                 return false;
  66
  67         if (map->volatile_reg)
  68                 return map->volatile_reg(map->dev, reg);
  69
  70         return true;
  71 }
  72
  73 bool regmap_precious(struct regmap *map, unsigned int reg)
  74 {
  75         if (!regmap_readable(map, reg))
  76                 return false;
  77
  78         if (map->precious_reg)
  79                 return map->precious_reg(map->dev, reg);
  80
  81         return false;
  82 }
  83
  84 static bool regmap_volatile_range(struct regmap *map, unsigned int reg,
  85         unsigned int num)
  86 {
  87         unsigned int i;
  88
  89         for (i = 0; i < num; i++)
  90                 if (!regmap_volatile(map, reg + i))
  91                         return false;
  92
  93         return true;
  94 }
  95
  96 static void regmap_format_2_6_write(struct regmap *map,
  97                                      unsigned int reg, unsigned int val)
  98 {
  99         u8 *out = map->work_buf;
 100
 101         *out = (reg << 6) | val;
 102 }
 103
 104 static void regmap_format_4_12_write(struct regmap *map,
 105                                      unsigned int reg, unsigned int val)
 106 {
 107         __be16 *out = map->work_buf;
 108         *out = cpu_to_be16((reg << 12) | val);
 109 }
 110
 111 static void regmap_format_7_9_write(struct regmap *map,
 112                                     unsigned int reg, unsigned int val)
 113 {
 114         __be16 *out = map->work_buf;
 115         *out = cpu_to_be16((reg << 9) | val);
 116 }
 117
 118 static void regmap_format_10_14_write(struct regmap *map,
 119                                     unsigned int reg, unsigned int val)
 120 {
 121         u8 *out = map->work_buf;
 122
 123         out[2] = val;
 124         out[1] = (val >> 8) | (reg << 6);
 125         out[0] = reg >> 2;
 126 }
 127
 128 static void regmap_format_8(void *buf, unsigned int val, unsigned int shift)
 129 {
 130         u8 *b = buf;
 131
 132         b[0] = val << shift;
 133 }
 134
 135 static void regmap_format_16_be(void *buf, unsigned int val, unsigned int shift)
 136 {
 137         __be16 *b = buf;
 138
 139         b[0] = cpu_to_be16(val << shift);
 140 }
 141
 142 static void regmap_format_16_native(void *buf, unsigned int val,
 143                                     unsigned int shift)
 144 {
 145         *(u16 *)buf = val << shift;
 146 }
 147
 148 static void regmap_format_24(void *buf, unsigned int val, unsigned int shift)
 149 {
 150         u8 *b = buf;
 151
 152         val <<= shift;
 153
 154         b[0] = val >> 16;
 155         b[1] = val >> 8;
 156         b[2] = val;
 157 }
 158
 159 static void regmap_format_32_be(void *buf, unsigned int val, unsigned int shift)
 160 {
 161         __be32 *b = buf;
 162
 163         b[0] = cpu_to_be32(val << shift);
 164 }
 165
 166 static void regmap_format_32_native(void *buf, unsigned int val,
 167                                     unsigned int shift)
 168 {
 169         *(u32 *)buf = val << shift;
 170 }
 171
 172 static unsigned int regmap_parse_8(void *buf)
 173 {
 174         u8 *b = buf;
 175
 176         return b[0];
 177 }
 178
 179 static unsigned int regmap_parse_16_be(void *buf)
 180 {
 181         __be16 *b = buf;
 182
 183         b[0] = be16_to_cpu(b[0]);
 184
 185         return b[0];
 186 }
 187
 188 static unsigned int regmap_parse_16_native(void *buf)
 189 {
 190         return *(u16 *)buf;
 191 }
 192
 193 static unsigned int regmap_parse_24(void *buf)
 194 {
 195         u8 *b = buf;
 196         unsigned int ret = b[2];
 197         ret |= ((unsigned int)b[1]) << 8;
 198         ret |= ((unsigned int)b[0]) << 16;
 199
 200         return ret;
 201 }
 202
 203 static unsigned int regmap_parse_32_be(void *buf)
 204 {
 205         __be32 *b = buf;
 206
 207         b[0] = be32_to_cpu(b[0]);
 208
 209         return b[0];
 210 }
 211
 212 static unsigned int regmap_parse_32_native(void *buf)
 213 {
 214         return *(u32 *)buf;
 215 }
 216
 217 static void regmap_lock_mutex(struct regmap *map)
 218 {
 219         mutex_lock(&map->mutex);
 220 }
 221
 222 static void regmap_unlock_mutex(struct regmap *map)
 223 {
 224         mutex_unlock(&map->mutex);
 225 }
 226
 227 static void regmap_lock_spinlock(struct regmap *map)
 228 {
 229         spin_lock(&map->spinlock);
 230 }
 231
 232 static void regmap_unlock_spinlock(struct regmap *map)
 233 {
 234         spin_unlock(&map->spinlock);
 235 }
 236
 237 static void dev_get_regmap_release(struct device *dev, void *res)
 238 {
 239         /*
 240          * We don't actually have anything to do here; the goal here
 241          * is not to manage the regmap but to provide a simple way to
 242          * get the regmap back given a struct device.
 243          */
 244 }
 245
 246 static bool _regmap_range_add(struct regmap *map,
 247                               struct regmap_range_node *data)
 248 {
 249         struct rb_root *root = &map->range_tree;
 250         struct rb_node **new = &(root->rb_node), *parent = NULL;
 251
 252         while (*new) {
 253                 struct regmap_range_node *this =
 254                         container_of(*new, struct regmap_range_node, node);
 255
 256                 parent = *new;
 257                 if (data->range_max < this->range_min)
 258                         new = &((*new)->rb_left);
 259                 else if (data->range_min > this->range_max)
 260                         new = &((*new)->rb_right);
 261                 else
 262                         return false;
 263         }
 264
 265         rb_link_node(&data->node, parent, new);
 266         rb_insert_color(&data->node, root);
 267
 268         return true;
 269 }
 270
 271 static struct regmap_range_node *_regmap_range_lookup(struct regmap *map,
 272                                                       unsigned int reg)
 273 {
 274         struct rb_node *node = map->range_tree.rb_node;
 275
 276         while (node) {
 277                 struct regmap_range_node *this =
 278                         container_of(node, struct regmap_range_node, node);
 279
 280                 if (reg < this->range_min)
 281                         node = node->rb_left;
 282                 else if (reg > this->range_max)
 283                         node = node->rb_right;
 284                 else
 285                         return this;
 286         }
 287
 288         return NULL;
 289 }
 290
 291 static void regmap_range_exit(struct regmap *map)
 292 {
 293         struct rb_node *next;
 294         struct regmap_range_node *range_node;
 295
 296         next = rb_first(&map->range_tree);
 297         while (next) {
 298                 range_node = rb_entry(next, struct regmap_range_node, node);
 299                 next = rb_next(&range_node->node);
 300                 rb_erase(&range_node->node, &map->range_tree);
 301                 kfree(range_node);
 302         }
 303
 304         kfree(map->selector_work_buf);
 305 }
 306
 307 /**
 308  * regmap_init(): Initialise register map
 309  *
 310  * @dev: Device that will be interacted with
 311  * @bus: Bus-specific callbacks to use with device
 312  * @bus_context: Data passed to bus-specific callbacks
 313  * @config: Configuration for register map
 314  *
 315  * The return value will be an ERR_PTR() on error or a valid pointer to
 316  * a struct regmap.  This function should generally not be called
 317  * directly, it should be called by bus-specific init functions.
 318  */
 319 struct regmap *regmap_init(struct device *dev,
 320                            const struct regmap_bus *bus,
 321                            void *bus_context,
 322                            const struct regmap_config *config)
 323 {
 324         struct regmap *map, **m;
 325         int ret = -EINVAL;
 326         enum regmap_endian reg_endian, val_endian;
 327         int i, j;
 328
 329         if (!bus || !config)
 330                 goto err;
 331
 332         map = kzalloc(sizeof(*map), GFP_KERNEL);
 333         if (map == NULL) {
 334                 ret = -ENOMEM;
 335                 goto err;
 336         }
 337
 338         if (bus->fast_io) {
 339                 spin_lock_init(&map->spinlock);
 340                 map->lock = regmap_lock_spinlock;
 341                 map->unlock = regmap_unlock_spinlock;
 342         } else {
 343                 mutex_init(&map->mutex);
 344                 map->lock = regmap_lock_mutex;
 345                 map->unlock = regmap_unlock_mutex;
 346         }
 347         map->format.reg_bytes = DIV_ROUND_UP(config->reg_bits, 8);
 348         map->format.pad_bytes = config->pad_bits / 8;
 349         map->format.val_bytes = DIV_ROUND_UP(config->val_bits, 8);
 350         map->format.buf_size = DIV_ROUND_UP(config->reg_bits +
 351                         config->val_bits + config->pad_bits, 8);
 352         map->reg_shift = config->pad_bits % 8;
 353         if (config->reg_stride)
 354                 map->reg_stride = config->reg_stride;
 355         else
 356                 map->reg_stride = 1;
 357         map->use_single_rw = config->use_single_rw;
 358         map->dev = dev;
 359         map->bus = bus;
 360         map->bus_context = bus_context;
 361         map->max_register = config->max_register;
 362         map->writeable_reg = config->writeable_reg;
 363         map->readable_reg = config->readable_reg;
 364         map->volatile_reg = config->volatile_reg;
 365         map->precious_reg = config->precious_reg;
 366         map->cache_type = config->cache_type;
 367         map->name = config->name;
 368
 369         if (config->read_flag_mask || config->write_flag_mask) {
 370                 map->read_flag_mask = config->read_flag_mask;
 371                 map->write_flag_mask = config->write_flag_mask;
 372         } else {
 373                 map->read_flag_mask = bus->read_flag_mask;
 374         }
 375
 376         reg_endian = config->reg_format_endian;
 377         if (reg_endian == REGMAP_ENDIAN_DEFAULT)
 378                 reg_endian = bus->reg_format_endian_default;
 379         if (reg_endian == REGMAP_ENDIAN_DEFAULT)
 380                 reg_endian = REGMAP_ENDIAN_BIG;
 381
 382         val_endian = config->val_format_endian;
 383         if (val_endian == REGMAP_ENDIAN_DEFAULT)
 384                 val_endian = bus->val_format_endian_default;
 385         if (val_endian == REGMAP_ENDIAN_DEFAULT)
 386                 val_endian = REGMAP_ENDIAN_BIG;
 387
 388         switch (config->reg_bits + map->reg_shift) {
 389         case 2:
 390                 switch (config->val_bits) {
 391                 case 6:
 392                         map->format.format_write = regmap_format_2_6_write;
 393                         break;
 394                 default:
 395                         goto err_map;
 396                 }
 397                 break;
 398
 399         case 4:
 400                 switch (config->val_bits) {
 401                 case 12:
 402                         map->format.format_write = regmap_format_4_12_write;
 403                         break;
 404                 default:
 405                         goto err_map;
 406                 }
 407                 break;
 408
 409         case 7:
 410                 switch (config->val_bits) {
 411                 case 9:
 412                         map->format.format_write = regmap_format_7_9_write;
 413                         break;
 414                 default:
 415                         goto err_map;
 416                 }
 417                 break;
 418
 419         case 10:
 420                 switch (config->val_bits) {
 421                 case 14:
 422                         map->format.format_write = regmap_format_10_14_write;
 423                         break;
 424                 default:
 425                         goto err_map;
 426                 }
 427                 break;
 428
 429         case 8:
 430                 map->format.format_reg = regmap_format_8;
 431                 break;
 432
 433         case 16:
 434                 switch (reg_endian) {
 435                 case REGMAP_ENDIAN_BIG:
 436                         map->format.format_reg = regmap_format_16_be;
 437                         break;
 438                 case REGMAP_ENDIAN_NATIVE:
 439                         map->format.format_reg = regmap_format_16_native;
 440                         break;
 441                 default:
 442                         goto err_map;
 443                 }
 444                 break;
 445
 446         case 32:
 447                 switch (reg_endian) {
 448                 case REGMAP_ENDIAN_BIG:
 449                         map->format.format_reg = regmap_format_32_be;
 450                         break;
 451                 case REGMAP_ENDIAN_NATIVE:
 452                         map->format.format_reg = regmap_format_32_native;
 453                         break;
 454                 default:
 455                         goto err_map;
 456                 }
 457                 break;
 458
 459         default:
 460                 goto err_map;
 461         }
 462
 463         switch (config->val_bits) {
 464         case 8:
 465                 map->format.format_val = regmap_format_8;
 466                 map->format.parse_val = regmap_parse_8;
 467                 break;
 468         case 16:
 469                 switch (val_endian) {
 470                 case REGMAP_ENDIAN_BIG:
 471                         map->format.format_val = regmap_format_16_be;
 472                         map->format.parse_val = regmap_parse_16_be;
 473                         break;
 474                 case REGMAP_ENDIAN_NATIVE:
 475                         map->format.format_val = regmap_format_16_native;
 476                         map->format.parse_val = regmap_parse_16_native;
 477                         break;
 478                 default:
 479                         goto err_map;
 480                 }
 481                 break;
 482         case 24:
 483                 if (val_endian != REGMAP_ENDIAN_BIG)
 484                         goto err_map;
 485                 map->format.format_val = regmap_format_24;
 486                 map->format.parse_val = regmap_parse_24;
 487                 break;
 488         case 32:
 489                 switch (val_endian) {
 490                 case REGMAP_ENDIAN_BIG:
 491                         map->format.format_val = regmap_format_32_be;
 492                         map->format.parse_val = regmap_parse_32_be;
 493                         break;
 494                 case REGMAP_ENDIAN_NATIVE:
 495                         map->format.format_val = regmap_format_32_native;
 496                         map->format.parse_val = regmap_parse_32_native;
 497                         break;
 498                 default:
 499                         goto err_map;
 500                 }
 501                 break;
 502         }
 503
 504         if (map->format.format_write) {
 505                 if ((reg_endian != REGMAP_ENDIAN_BIG) ||
 506                     (val_endian != REGMAP_ENDIAN_BIG))
 507                         goto err_map;
 508                 map->use_single_rw = true;
 509         }
 510
 511         if (!map->format.format_write &&
 512             !(map->format.format_reg && map->format.format_val))
 513                 goto err_map;
 514
 515         map->work_buf = kzalloc(map->format.buf_size, GFP_KERNEL);
 516         if (map->work_buf == NULL) {
 517                 ret = -ENOMEM;
 518                 goto err_map;
 519         }
 520
 521         map->range_tree = RB_ROOT;
 522         for (i = 0; i < config->n_ranges; i++) {
 523                 const struct regmap_range_cfg *range_cfg = &config->ranges[i];
 524                 struct regmap_range_node *new;
 525
 526                 /* Sanity check */
 527                 if (range_cfg->range_max < range_cfg->range_min ||
 528                     range_cfg->range_max > map->max_register ||
 529                     range_cfg->selector_reg > map->max_register ||
 530                     range_cfg->window_len == 0)
 531                         goto err_range;
 532
 533                 /* Make sure, that this register range has no selector
 534                    or data window within its boundary */
 535                 for (j = 0; j < config->n_ranges; j++) {
 536                         unsigned sel_reg = config->ranges[j].selector_reg;
 537                         unsigned win_min = config->ranges[j].window_start;
 538                         unsigned win_max = win_min +
 539                                            config->ranges[j].window_len - 1;
 540
 541                         if (range_cfg->range_min <= sel_reg &&
 542                             sel_reg <= range_cfg->range_max) {
 543                                 goto err_range;
 544                         }
 545
 546                         if (!(win_max < range_cfg->range_min ||
 547                               win_min > range_cfg->range_max)) {
 548                                 goto err_range;
 549                         }
 550                 }
 551
 552                 new = kzalloc(sizeof(*new), GFP_KERNEL);
 553                 if (new == NULL) {
 554                         ret = -ENOMEM;
 555                         goto err_range;
 556                 }
 557
 558                 new->range_min = range_cfg->range_min;
 559                 new->range_max = range_cfg->range_max;
 560                 new->selector_reg = range_cfg->selector_reg;
 561                 new->selector_mask = range_cfg->selector_mask;
 562                 new->selector_shift = range_cfg->selector_shift;
 563                 new->window_start = range_cfg->window_start;
 564                 new->window_len = range_cfg->window_len;
 565
 566                 if (_regmap_range_add(map, new) == false) {
 567                         kfree(new);
 568                         goto err_range;
 569                 }
 570
 571                 if (map->selector_work_buf == NULL) {
 572                         map->selector_work_buf =
 573                                 kzalloc(map->format.buf_size, GFP_KERNEL);
 574                         if (map->selector_work_buf == NULL) {
 575                                 ret = -ENOMEM;
 576                                 goto err_range;
 577                         }
 578                 }
 579         }
 580
 581         ret = regcache_init(map, config);
 582         if (ret < 0)
 583                 goto err_range;
 584
 585         regmap_debugfs_init(map, config->name);
 586
 587         /* Add a devres resource for dev_get_regmap() */
 588         m = devres_alloc(dev_get_regmap_release, sizeof(*m), GFP_KERNEL);
 589         if (!m) {
 590                 ret = -ENOMEM;
 591                 goto err_debugfs;
 592         }
 593         *m = map;
 594         devres_add(dev, m);
 595
 596         return map;
 597
 598 err_debugfs:
 599         regmap_debugfs_exit(map);
 600         regcache_exit(map);
 601 err_range:
 602         regmap_range_exit(map);
 603         kfree(map->work_buf);
 604 err_map:
 605         kfree(map);
 606 err:
 607         return ERR_PTR(ret);
 608 }
 609 EXPORT_SYMBOL_GPL(regmap_init);
 610
 611 static void devm_regmap_release(struct device *dev, void *res)
 612 {
 613         regmap_exit(*(struct regmap **)res);
 614 }
 615
 616 /**
 617  * devm_regmap_init(): Initialise managed register map
 618  *
 619  * @dev: Device that will be interacted with
 620  * @bus: Bus-specific callbacks to use with device
 621  * @bus_context: Data passed to bus-specific callbacks
 622  * @config: Configuration for register map
 623  *
 624  * The return value will be an ERR_PTR() on error or a valid pointer
 625  * to a struct regmap.  This function should generally not be called
 626  * directly, it should be called by bus-specific init functions.  The
 627  * map will be automatically freed by the device management code.
 628  */
 629 struct regmap *devm_regmap_init(struct device *dev,
 630                                 const struct regmap_bus *bus,
 631                                 void *bus_context,
 632                                 const struct regmap_config *config)
 633 {
 634         struct regmap **ptr, *regmap;
 635
 636         ptr = devres_alloc(devm_regmap_release, sizeof(*ptr), GFP_KERNEL);
 637         if (!ptr)
 638                 return ERR_PTR(-ENOMEM);
 639
 640         regmap = regmap_init(dev, bus, bus_context, config);
 641         if (!IS_ERR(regmap)) {
 642                 *ptr = regmap;
 643                 devres_add(dev, ptr);
 644         } else {
 645                 devres_free(ptr);
 646         }
 647
 648         return regmap;
 649 }
 650 EXPORT_SYMBOL_GPL(devm_regmap_init);
 651
 652 /**
 653  * regmap_reinit_cache(): Reinitialise the current register cache
 654  *
 655  * @map: Register map to operate on.
 656  * @config: New configuration.  Only the cache data will be used.
 657  *
 658  * Discard any existing register cache for the map and initialize a
 659  * new cache.  This can be used to restore the cache to defaults or to
 660  * update the cache configuration to reflect runtime discovery of the
 661  * hardware.
 662  */
 663 int regmap_reinit_cache(struct regmap *map, const struct regmap_config *config)
 664 {
 665         int ret;
 666
 667         map->lock(map);
 668
 669         regcache_exit(map);
 670         regmap_debugfs_exit(map);
 671
 672         map->max_register = config->max_register;
 673         map->writeable_reg = config->writeable_reg;
 674         map->readable_reg = config->readable_reg;
 675         map->volatile_reg = config->volatile_reg;
 676         map->precious_reg = config->precious_reg;
 677         map->cache_type = config->cache_type;
 678
 679         regmap_debugfs_init(map, config->name);
 680
 681         map->cache_bypass = false;
 682         map->cache_only = false;
 683
 684         ret = regcache_init(map, config);
 685
 686         map->unlock(map);
 687
 688         return ret;
 689 }
 690 EXPORT_SYMBOL_GPL(regmap_reinit_cache);
 691
 692 /**
 693  * regmap_exit(): Free a previously allocated register map
 694  */
 695 void regmap_exit(struct regmap *map)
 696 {
 697         regcache_exit(map);
 698         regmap_debugfs_exit(map);
 699         regmap_range_exit(map);
 700         if (map->bus->free_context)
 701                 map->bus->free_context(map->bus_context);
 702         kfree(map->work_buf);
 703         kfree(map);
 704 }
 705 EXPORT_SYMBOL_GPL(regmap_exit);
 706
 707 static int dev_get_regmap_match(struct device *dev, void *res, void *data)
 708 {
 709         struct regmap **r = res;
 710         if (!r || !*r) {
 711                 WARN_ON(!r || !*r);
 712                 return 0;
 713         }
 714
 715         /* If the user didn't specify a name match any */
 716         if (data)
 717                 return (*r)->name == data;
 718         else
 719                 return 1;
 720 }
 721
 722 /**
 723  * dev_get_regmap(): Obtain the regmap (if any) for a device
 724  *
 725  * @dev: Device to retrieve the map for
 726  * @name: Optional name for the register map, usually NULL.
 727  *
 728  * Returns the regmap for the device if one is present, or NULL.  If
 729  * name is specified then it must match the name specified when
 730  * registering the device, if it is NULL then the first regmap found
 731  * will be used.  Devices with multiple register maps are very rare,
 732  * generic code should normally not need to specify a name.
 733  */
 734 struct regmap *dev_get_regmap(struct device *dev, const char *name)
 735 {
 736         struct regmap **r = devres_find(dev, dev_get_regmap_release,
 737                                         dev_get_regmap_match, (void *)name);
 738
 739         if (!r)
 740                 return NULL;
 741         return *r;
 742 }
 743 EXPORT_SYMBOL_GPL(dev_get_regmap);
 744
 745 static int _regmap_select_page(struct regmap *map, unsigned int *reg,
 746                                unsigned int val_num)
 747 {
 748         struct regmap_range_node *range;
 749         void *orig_work_buf;
 750         unsigned int win_offset;
 751         unsigned int win_page;
 752         bool page_chg;
 753         int ret;
 754
 755         range = _regmap_range_lookup(map, *reg);
 756         if (range) {
 757                 win_offset = (*reg - range->range_min) % range->window_len;
 758                 win_page = (*reg - range->range_min) / range->window_len;
 759
 760                 if (val_num > 1) {
 761                         /* Bulk write shouldn't cross range boundary */
 762                         if (*reg + val_num - 1 > range->range_max)
 763                                 return -EINVAL;
 764
 765                         /* ... or single page boundary */
 766                         if (val_num > range->window_len - win_offset)
 767                                 return -EINVAL;
 768                 }
 769
 770                 /* It is possible to have selector register inside data window.
 771                    In that case, selector register is located on every page and
 772                    it needs no page switching, when accessed alone. */
 773                 if (val_num > 1 ||
 774                     range->window_start + win_offset != range->selector_reg) {
 775                         /* Use separate work_buf during page switching */
 776                         orig_work_buf = map->work_buf;
 777                         map->work_buf = map->selector_work_buf;
 778
 779                         ret = _regmap_update_bits(map, range->selector_reg,
 780                                         range->selector_mask,
 781                                         win_page << range->selector_shift,
 782                                         &page_chg);
 783
 784                         map->work_buf = orig_work_buf;
 785
 786                         if (ret < 0)
 787                                 return ret;
 788                 }
 789
 790                 *reg = range->window_start + win_offset;
 791         }
 792
 793         return 0;
 794 }
 795
 796 static int _regmap_raw_write(struct regmap *map, unsigned int reg,
 797                              const void *val, size_t val_len)
 798 {
 799         u8 *u8 = map->work_buf;
 800         void *buf;
 801         int ret = -ENOTSUPP;
 802         size_t len;
 803         int i;
 804
 805         /* Check for unwritable registers before we start */
 806         if (map->writeable_reg)
 807                 for (i = 0; i < val_len / map->format.val_bytes; i++)
 808                         if (!map->writeable_reg(map->dev,
 809                                                 reg + (i * map->reg_stride)))
 810                                 return -EINVAL;
 811
 812         if (!map->cache_bypass && map->format.parse_val) {
 813                 unsigned int ival;
 814                 int val_bytes = map->format.val_bytes;
 815                 for (i = 0; i < val_len / val_bytes; i++) {
 816                         memcpy(map->work_buf, val + (i * val_bytes), val_bytes);
 817                         ival = map->format.parse_val(map->work_buf);
 818                         ret = regcache_write(map, reg + (i * map->reg_stride),
 819                                              ival);
 820                         if (ret) {
 821                                 dev_err(map->dev,
 822                                    "Error in caching of register: %u ret: %d\n",
 823                                         reg + i, ret);
 824                                 return ret;
 825                         }
 826                 }
 827                 if (map->cache_only) {
 828                         map->cache_dirty = true;
 829                         return 0;
 830                 }
 831         }
 832
 833         ret = _regmap_select_page(map, &reg, val_len / map->format.val_bytes);
 834         if (ret < 0)
 835                 return ret;
 836
 837         map->format.format_reg(map->work_buf, reg, map->reg_shift);
 838
 839         u8[0] |= map->write_flag_mask;
 840
 841         trace_regmap_hw_write_start(map->dev, reg,
 842                                     val_len / map->format.val_bytes);
 843
 844         /* If we're doing a single register write we can probably just
 845          * send the work_buf directly, otherwise try to do a gather
 846          * write.
 847          */
 848         if (val == (map->work_buf + map->format.pad_bytes +
 849                     map->format.reg_bytes))
 850                 ret = map->bus->write(map->bus_context, map->work_buf,
 851                                       map->format.reg_bytes +
 852                                       map->format.pad_bytes +
 853                                       val_len);
 854         else if (map->bus->gather_write)
 855                 ret = map->bus->gather_write(map->bus_context, map->work_buf,
 856                                              map->format.reg_bytes +
 857                                              map->format.pad_bytes,
 858                                              val, val_len);
 859
 860         /* If that didn't work fall back on linearising by hand. */
 861         if (ret == -ENOTSUPP) {
 862                 len = map->format.reg_bytes + map->format.pad_bytes + val_len;
 863                 buf = kzalloc(len, GFP_KERNEL);
 864                 if (!buf)
 865                         return -ENOMEM;
 866
 867                 memcpy(buf, map->work_buf, map->format.reg_bytes);
 868                 memcpy(buf + map->format.reg_bytes + map->format.pad_bytes,
 869                        val, val_len);
 870                 ret = map->bus->write(map->bus_context, buf, len);
 871
 872                 kfree(buf);
 873         }
 874
 875         trace_regmap_hw_write_done(map->dev, reg,
 876                                    val_len / map->format.val_bytes);
 877
 878         return ret;
 879 }
 880
 881 int _regmap_write(struct regmap *map, unsigned int reg,
 882                   unsigned int val)
 883 {
 884         int ret;
 885         BUG_ON(!map->format.format_write && !map->format.format_val);
 886
 887         if (!map->cache_bypass && map->format.format_write) {
 888                 ret = regcache_write(map, reg, val);
 889                 if (ret != 0)
 890                         return ret;
 891                 if (map->cache_only) {
 892                         map->cache_dirty = true;
 893                         return 0;
 894                 }
 895         }
 896
 897 #ifdef LOG_DEVICE
 898         if (strcmp(dev_name(map->dev), LOG_DEVICE) == 0)
 899                 dev_info(map->dev, "%x <= %x\n", reg, val);
 900 #endif
 901
 902         trace_regmap_reg_write(map->dev, reg, val);
 903
 904         if (map->format.format_write) {
 905                 ret = _regmap_select_page(map, &reg, 1);
 906                 if (ret < 0)
 907                         return ret;
 908
 909                 map->format.format_write(map, reg, val);
 910
 911                 trace_regmap_hw_write_start(map->dev, reg, 1);
 912
 913                 ret = map->bus->write(map->bus_context, map->work_buf,
 914                                       map->format.buf_size);
 915
 916                 trace_regmap_hw_write_done(map->dev, reg, 1);
 917
 918                 return ret;
 919         } else {
 920                 map->format.format_val(map->work_buf + map->format.reg_bytes
 921                                        + map->format.pad_bytes, val, 0);
 922                 return _regmap_raw_write(map, reg,
 923                                          map->work_buf +
 924                                          map->format.reg_bytes +
 925                                          map->format.pad_bytes,
 926                                          map->format.val_bytes);
 927         }
 928 }
 929
 930 /**
 931  * regmap_write(): Write a value to a single register
 932  *
 933  * @map: Register map to write to
 934  * @reg: Register to write to
 935  * @val: Value to be written
 936  *
 937  * A value of zero will be returned on success, a negative errno will
 938  * be returned in error cases.
 939  */
 940 int regmap_write(struct regmap *map, unsigned int reg, unsigned int val)
 941 {
 942         int ret;
 943
 944         if (reg % map->reg_stride)
 945                 return -EINVAL;
 946
 947         map->lock(map);
 948
 949         ret = _regmap_write(map, reg, val);
 950
 951         map->unlock(map);
 952
 953         return ret;
 954 }
 955 EXPORT_SYMBOL_GPL(regmap_write);
 956
 957 /**
 958  * regmap_raw_write(): Write raw values to one or more registers
 959  *
 960  * @map: Register map to write to
 961  * @reg: Initial register to write to
 962  * @val: Block of data to be written, laid out for direct transmission to the
 963  *       device
 964  * @val_len: Length of data pointed to by val.
 965  *
 966  * This function is intended to be used for things like firmware
 967  * download where a large block of data needs to be transferred to the
 968  * device.  No formatting will be done on the data provided.
 969  *
 970  * A value of zero will be returned on success, a negative errno will
 971  * be returned in error cases.
 972  */
 973 int regmap_raw_write(struct regmap *map, unsigned int reg,
 974                      const void *val, size_t val_len)
 975 {
 976         int ret;
 977
 978         if (val_len % map->format.val_bytes)
 979                 return -EINVAL;
 980         if (reg % map->reg_stride)
 981                 return -EINVAL;
 982
 983         map->lock(map);
 984
 985         ret = _regmap_raw_write(map, reg, val, val_len);
 986
 987         map->unlock(map);
 988
 989         return ret;
 990 }
 991 EXPORT_SYMBOL_GPL(regmap_raw_write);
 992
 993 /*
 994  * regmap_bulk_write(): Write multiple registers to the device
 995  *
 996  * @map: Register map to write to
 997  * @reg: First register to be write from
 998  * @val: Block of data to be written, in native register size for device
 999  * @val_count: Number of registers to write
1000  *
1001  * This function is intended to be used for writing a large block of
1002  * data to be device either in single transfer or multiple transfer.
1003  *
1004  * A value of zero will be returned on success, a negative errno will
1005  * be returned in error cases.
1006  */
1007 int regmap_bulk_write(struct regmap *map, unsigned int reg, const void *val,
1008                      size_t val_count)
1009 {
1010         int ret = 0, i;
1011         size_t val_bytes = map->format.val_bytes;
1012         void *wval;
1013
1014         if (!map->format.parse_val)
1015                 return -EINVAL;
1016         if (reg % map->reg_stride)
1017                 return -EINVAL;
1018
1019         map->lock(map);
1020
1021         /* No formatting is require if val_byte is 1 */
1022         if (val_bytes == 1) {
1023                 wval = (void *)val;
1024         } else {
1025                 wval = kmemdup(val, val_count * val_bytes, GFP_KERNEL);
1026                 if (!wval) {
1027                         ret = -ENOMEM;
1028                         dev_err(map->dev, "Error in memory allocation\n");
1029                         goto out;
1030                 }
1031                 for (i = 0; i < val_count * val_bytes; i += val_bytes)
1032                         map->format.parse_val(wval + i);
1033         }
1034         /*
1035          * Some devices does not support bulk write, for
1036          * them we have a series of single write operations.
1037          */
1038         if (map->use_single_rw) {
1039                 for (i = 0; i < val_count; i++) {
1040                         ret = regmap_raw_write(map,
1041                                                 reg + (i * map->reg_stride),
1042                                                 val + (i * val_bytes),
1043                                                 val_bytes);
1044                         if (ret != 0)
1045                                 return ret;
1046                 }
1047         } else {
1048                 ret = _regmap_raw_write(map, reg, wval, val_bytes * val_count);
1049         }
1050
1051         if (val_bytes != 1)
1052                 kfree(wval);
1053
1054 out:
1055         map->unlock(map);
1056         return ret;
1057 }
1058 EXPORT_SYMBOL_GPL(regmap_bulk_write);
1059
1060 static int _regmap_raw_read(struct regmap *map, unsigned int reg, void *val,
1061                             unsigned int val_len)
1062 {
1063         u8 *u8 = map->work_buf;
1064         int ret;
1065
1066         ret = _regmap_select_page(map, &reg, val_len / map->format.val_bytes);
1067         if (ret < 0)
1068                 return ret;
1069
1070         map->format.format_reg(map->work_buf, reg, map->reg_shift);
1071
1072         /*
1073          * Some buses or devices flag reads by setting the high bits in the
1074          * register addresss; since it's always the high bits for all
1075          * current formats we can do this here rather than in
1076          * formatting.  This may break if we get interesting formats.
1077          */
1078         u8[0] |= map->read_flag_mask;
1079
1080         trace_regmap_hw_read_start(map->dev, reg,
1081                                    val_len / map->format.val_bytes);
1082
1083         ret = map->bus->read(map->bus_context, map->work_buf,
1084                              map->format.reg_bytes + map->format.pad_bytes,
1085                              val, val_len);
1086
1087         trace_regmap_hw_read_done(map->dev, reg,
1088                                   val_len / map->format.val_bytes);
1089
1090         return ret;
1091 }
1092
1093 static int _regmap_read(struct regmap *map, unsigned int reg,
1094                         unsigned int *val)
1095 {
1096         int ret;
1097
1098         if (!map->cache_bypass) {
1099                 ret = regcache_read(map, reg, val);
1100                 if (ret == 0)
1101                         return 0;
1102         }
1103
1104         if (!map->format.parse_val)
1105                 return -EINVAL;
1106
1107         if (map->cache_only)
1108                 return -EBUSY;
1109
1110         ret = _regmap_raw_read(map, reg, map->work_buf, map->format.val_bytes);
1111         if (ret == 0) {
1112                 *val = map->format.parse_val(map->work_buf);
1113
1114 #ifdef LOG_DEVICE
1115                 if (strcmp(dev_name(map->dev), LOG_DEVICE) == 0)
1116                         dev_info(map->dev, "%x => %x\n", reg, *val);
1117 #endif
1118
1119                 trace_regmap_reg_read(map->dev, reg, *val);
1120         }
1121
1122         if (ret == 0 && !map->cache_bypass)
1123                 regcache_write(map, reg, *val);
1124
1125         return ret;
1126 }
1127
1128 /**
1129  * regmap_read(): Read a value from a single register
1130  *
1131  * @map: Register map to write to
1132  * @reg: Register to be read from
1133  * @val: Pointer to store read value
1134  *
1135  * A value of zero will be returned on success, a negative errno will
1136  * be returned in error cases.
1137  */
1138 int regmap_read(struct regmap *map, unsigned int reg, unsigned int *val)
1139 {
1140         int ret;
1141
1142         if (reg % map->reg_stride)
1143                 return -EINVAL;
1144
1145         map->lock(map);
1146
1147         ret = _regmap_read(map, reg, val);
1148
1149         map->unlock(map);
1150
1151         return ret;
1152 }
1153 EXPORT_SYMBOL_GPL(regmap_read);
1154
1155 /**
1156  * regmap_raw_read(): Read raw data from the device
1157  *
1158  * @map: Register map to write to
1159  * @reg: First register to be read from
1160  * @val: Pointer to store read value
1161  * @val_len: Size of data to read
1162  *
1163  * A value of zero will be returned on success, a negative errno will
1164  * be returned in error cases.
1165  */
1166 int regmap_raw_read(struct regmap *map, unsigned int reg, void *val,
1167                     size_t val_len)
1168 {
1169         size_t val_bytes = map->format.val_bytes;
1170         size_t val_count = val_len / val_bytes;
1171         unsigned int v;
1172         int ret, i;
1173
1174         if (val_len % map->format.val_bytes)
1175                 return -EINVAL;
1176         if (reg % map->reg_stride)
1177                 return -EINVAL;
1178
1179         map->lock(map);
1180
1181         if (regmap_volatile_range(map, reg, val_count) || map->cache_bypass ||
1182             map->cache_type == REGCACHE_NONE) {
1183                 /* Physical block read if there's no cache involved */
1184                 ret = _regmap_raw_read(map, reg, val, val_len);
1185
1186         } else {
1187                 /* Otherwise go word by word for the cache; should be low
1188                  * cost as we expect to hit the cache.
1189                  */
1190                 for (i = 0; i < val_count; i++) {
1191                         ret = _regmap_read(map, reg + (i * map->reg_stride),
1192                                            &v);
1193                         if (ret != 0)
1194                                 goto out;
1195
1196                         map->format.format_val(val + (i * val_bytes), v, 0);
1197                 }
1198         }
1199
1200  out:
1201         map->unlock(map);
1202
1203         return ret;
1204 }
1205 EXPORT_SYMBOL_GPL(regmap_raw_read);
1206
1207 /**
1208  * regmap_bulk_read(): Read multiple registers from the device
1209  *
1210  * @map: Register map to write to
1211  * @reg: First register to be read from
1212  * @val: Pointer to store read value, in native register size for device
1213  * @val_count: Number of registers to read
1214  *
1215  * A value of zero will be returned on success, a negative errno will
1216  * be returned in error cases.
1217  */
1218 int regmap_bulk_read(struct regmap *map, unsigned int reg, void *val,
1219                      size_t val_count)
1220 {
1221         int ret, i;
1222         size_t val_bytes = map->format.val_bytes;
1223         bool vol = regmap_volatile_range(map, reg, val_count);
1224
1225         if (!map->format.parse_val)
1226                 return -EINVAL;
1227         if (reg % map->reg_stride)
1228                 return -EINVAL;
1229
1230         if (vol || map->cache_type == REGCACHE_NONE) {
1231                 /*
1232                  * Some devices does not support bulk read, for
1233                  * them we have a series of single read operations.
1234                  */
1235                 if (map->use_single_rw) {
1236                         for (i = 0; i < val_count; i++) {
1237                                 ret = regmap_raw_read(map,
1238                                                 reg + (i * map->reg_stride),
1239                                                 val + (i * val_bytes),
1240                                                 val_bytes);
1241                                 if (ret != 0)
1242                                         return ret;
1243                         }
1244                 } else {
1245                         ret = regmap_raw_read(map, reg, val,
1246                                               val_bytes * val_count);
1247                         if (ret != 0)
1248                                 return ret;
1249                 }
1250
1251                 for (i = 0; i < val_count * val_bytes; i += val_bytes)
1252                         map->format.parse_val(val + i);
1253         } else {
1254                 for (i = 0; i < val_count; i++) {
1255                         unsigned int ival;
1256                         ret = regmap_read(map, reg + (i * map->reg_stride),
1257                                           &ival);
1258                         if (ret != 0)
1259                                 return ret;
1260                         memcpy(val + (i * val_bytes), &ival, val_bytes);
1261                 }
1262         }
1263
1264         return 0;
1265 }
1266 EXPORT_SYMBOL_GPL(regmap_bulk_read);
1267
1268 static int _regmap_update_bits(struct regmap *map, unsigned int reg,
1269                                unsigned int mask, unsigned int val,
1270                                bool *change)
1271 {
1272         int ret;
1273         unsigned int tmp, orig;
1274
1275         ret = _regmap_read(map, reg, &orig);
1276         if (ret != 0)
1277                 return ret;
1278
1279         tmp = orig & ~mask;
1280         tmp |= val & mask;
1281
1282         if (tmp != orig) {
1283                 ret = _regmap_write(map, reg, tmp);
1284                 *change = true;
1285         } else {
1286                 *change = false;
1287         }
1288
1289         return ret;
1290 }
1291
1292 /**
1293  * regmap_update_bits: Perform a read/modify/write cycle on the register map
1294  *
1295  * @map: Register map to update
1296  * @reg: Register to update
1297  * @mask: Bitmask to change
1298  * @val: New value for bitmask
1299  *
1300  * Returns zero for success, a negative number on error.
1301  */
1302 int regmap_update_bits(struct regmap *map, unsigned int reg,
1303                        unsigned int mask, unsigned int val)
1304 {
1305         bool change;
1306         int ret;
1307
1308         map->lock(map);
1309         ret = _regmap_update_bits(map, reg, mask, val, &change);
1310         map->unlock(map);
1311
1312         return ret;
1313 }
1314 EXPORT_SYMBOL_GPL(regmap_update_bits);
1315
1316 /**
1317  * regmap_update_bits_check: Perform a read/modify/write cycle on the
1318  *                           register map and report if updated
1319  *
1320  * @map: Register map to update
1321  * @reg: Register to update
1322  * @mask: Bitmask to change
1323  * @val: New value for bitmask
1324  * @change: Boolean indicating if a write was done
1325  *
1326  * Returns zero for success, a negative number on error.
1327  */
1328 int regmap_update_bits_check(struct regmap *map, unsigned int reg,
1329                              unsigned int mask, unsigned int val,
1330                              bool *change)
1331 {
1332         int ret;
1333
1334         map->lock(map);
1335         ret = _regmap_update_bits(map, reg, mask, val, change);
1336         map->unlock(map);
1337         return ret;
1338 }
1339 EXPORT_SYMBOL_GPL(regmap_update_bits_check);
1340
1341 /**
1342  * regmap_register_patch: Register and apply register updates to be applied
1343  *                        on device initialistion
1344  *
1345  * @map: Register map to apply updates to.
1346  * @regs: Values to update.
1347  * @num_regs: Number of entries in regs.
1348  *
1349  * Register a set of register updates to be applied to the device
1350  * whenever the device registers are synchronised with the cache and
1351  * apply them immediately.  Typically this is used to apply
1352  * corrections to be applied to the device defaults on startup, such
1353  * as the updates some vendors provide to undocumented registers.
1354  */
1355 int regmap_register_patch(struct regmap *map, const struct reg_default *regs,
1356                           int num_regs)
1357 {
1358         int i, ret;
1359         bool bypass;
1360
1361         /* If needed the implementation can be extended to support this */
1362         if (map->patch)
1363                 return -EBUSY;
1364
1365         map->lock(map);
1366
1367         bypass = map->cache_bypass;
1368
1369         map->cache_bypass = true;
1370
1371         /* Write out first; it's useful to apply even if we fail later. */
1372         for (i = 0; i < num_regs; i++) {
1373                 ret = _regmap_write(map, regs[i].reg, regs[i].def);
1374                 if (ret != 0) {
1375                         dev_err(map->dev, "Failed to write %x = %x: %d\n",
1376                                 regs[i].reg, regs[i].def, ret);
1377                         goto out;
1378                 }
1379         }
1380
1381         map->patch = kcalloc(num_regs, sizeof(struct reg_default), GFP_KERNEL);
1382         if (map->patch != NULL) {
1383                 memcpy(map->patch, regs,
1384                        num_regs * sizeof(struct reg_default));
1385                 map->patch_regs = num_regs;
1386         } else {
1387                 ret = -ENOMEM;
1388         }
1389
1390 out:
1391         map->cache_bypass = bypass;
1392
1393         map->unlock(map);
1394
1395         return ret;
1396 }
1397 EXPORT_SYMBOL_GPL(regmap_register_patch);
1398
1399 /*
1400  * regmap_get_val_bytes(): Report the size of a register value
1401  *
1402  * Report the size of a register value, mainly intended to for use by
1403  * generic infrastructure built on top of regmap.
1404  */
1405 int regmap_get_val_bytes(struct regmap *map)
1406 {
1407         if (map->format.format_write)
1408                 return -EINVAL;
1409
1410         return map->format.val_bytes;
1411 }
1412 EXPORT_SYMBOL_GPL(regmap_get_val_bytes);
1413
1414 static int __init regmap_initcall(void)
1415 {
1416         regmap_debugfs_initcall();
1417
1418         return 0;
1419 }
1420 postcore_initcall(regmap_initcall);