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  * No explicit locking is done here, the user needs to ensure that
 664  * this function will not race with other calls to regmap.
 665  */
 666 int regmap_reinit_cache(struct regmap *map, const struct regmap_config *config)
 667 {
 668         regcache_exit(map);
 669         regmap_debugfs_exit(map);
 670
 671         map->max_register = config->max_register;
 672         map->writeable_reg = config->writeable_reg;
 673         map->readable_reg = config->readable_reg;
 674         map->volatile_reg = config->volatile_reg;
 675         map->precious_reg = config->precious_reg;
 676         map->cache_type = config->cache_type;
 677
 678         regmap_debugfs_init(map, config->name);
 679
 680         map->cache_bypass = false;
 681         map->cache_only = false;
 682
 683         return regcache_init(map, config);
 684 }
 685 EXPORT_SYMBOL_GPL(regmap_reinit_cache);
 686
 687 /**
 688  * regmap_exit(): Free a previously allocated register map
 689  */
 690 void regmap_exit(struct regmap *map)
 691 {
 692         regcache_exit(map);
 693         regmap_debugfs_exit(map);
 694         regmap_range_exit(map);
 695         if (map->bus->free_context)
 696                 map->bus->free_context(map->bus_context);
 697         kfree(map->work_buf);
 698         kfree(map);
 699 }
 700 EXPORT_SYMBOL_GPL(regmap_exit);
 701
 702 static int dev_get_regmap_match(struct device *dev, void *res, void *data)
 703 {
 704         struct regmap **r = res;
 705         if (!r || !*r) {
 706                 WARN_ON(!r || !*r);
 707                 return 0;
 708         }
 709
 710         /* If the user didn't specify a name match any */
 711         if (data)
 712                 return (*r)->name == data;
 713         else
 714                 return 1;
 715 }
 716
 717 /**
 718  * dev_get_regmap(): Obtain the regmap (if any) for a device
 719  *
 720  * @dev: Device to retrieve the map for
 721  * @name: Optional name for the register map, usually NULL.
 722  *
 723  * Returns the regmap for the device if one is present, or NULL.  If
 724  * name is specified then it must match the name specified when
 725  * registering the device, if it is NULL then the first regmap found
 726  * will be used.  Devices with multiple register maps are very rare,
 727  * generic code should normally not need to specify a name.
 728  */
 729 struct regmap *dev_get_regmap(struct device *dev, const char *name)
 730 {
 731         struct regmap **r = devres_find(dev, dev_get_regmap_release,
 732                                         dev_get_regmap_match, (void *)name);
 733
 734         if (!r)
 735                 return NULL;
 736         return *r;
 737 }
 738 EXPORT_SYMBOL_GPL(dev_get_regmap);
 739
 740 static int _regmap_select_page(struct regmap *map, unsigned int *reg,
 741                                unsigned int val_num)
 742 {
 743         struct regmap_range_node *range;
 744         void *orig_work_buf;
 745         unsigned int win_offset;
 746         unsigned int win_page;
 747         bool page_chg;
 748         int ret;
 749
 750         range = _regmap_range_lookup(map, *reg);
 751         if (range) {
 752                 win_offset = (*reg - range->range_min) % range->window_len;
 753                 win_page = (*reg - range->range_min) / range->window_len;
 754
 755                 if (val_num > 1) {
 756                         /* Bulk write shouldn't cross range boundary */
 757                         if (*reg + val_num - 1 > range->range_max)
 758                                 return -EINVAL;
 759
 760                         /* ... or single page boundary */
 761                         if (val_num > range->window_len - win_offset)
 762                                 return -EINVAL;
 763                 }
 764
 765                 /* It is possible to have selector register inside data window.
 766                    In that case, selector register is located on every page and
 767                    it needs no page switching, when accessed alone. */
 768                 if (val_num > 1 ||
 769                     range->window_start + win_offset != range->selector_reg) {
 770                         /* Use separate work_buf during page switching */
 771                         orig_work_buf = map->work_buf;
 772                         map->work_buf = map->selector_work_buf;
 773
 774                         ret = _regmap_update_bits(map, range->selector_reg,
 775                                         range->selector_mask,
 776                                         win_page << range->selector_shift,
 777                                         &page_chg);
 778
 779                         map->work_buf = orig_work_buf;
 780
 781                         if (ret < 0)
 782                                 return ret;
 783                 }
 784
 785                 *reg = range->window_start + win_offset;
 786         }
 787
 788         return 0;
 789 }
 790
 791 static int _regmap_raw_write(struct regmap *map, unsigned int reg,
 792                              const void *val, size_t val_len)
 793 {
 794         u8 *u8 = map->work_buf;
 795         void *buf;
 796         int ret = -ENOTSUPP;
 797         size_t len;
 798         int i;
 799
 800         /* Check for unwritable registers before we start */
 801         if (map->writeable_reg)
 802                 for (i = 0; i < val_len / map->format.val_bytes; i++)
 803                         if (!map->writeable_reg(map->dev,
 804                                                 reg + (i * map->reg_stride)))
 805                                 return -EINVAL;
 806
 807         if (!map->cache_bypass && map->format.parse_val) {
 808                 unsigned int ival;
 809                 int val_bytes = map->format.val_bytes;
 810                 for (i = 0; i < val_len / val_bytes; i++) {
 811                         memcpy(map->work_buf, val + (i * val_bytes), val_bytes);
 812                         ival = map->format.parse_val(map->work_buf);
 813                         ret = regcache_write(map, reg + (i * map->reg_stride),
 814                                              ival);
 815                         if (ret) {
 816                                 dev_err(map->dev,
 817                                    "Error in caching of register: %u ret: %d\n",
 818                                         reg + i, ret);
 819                                 return ret;
 820                         }
 821                 }
 822                 if (map->cache_only) {
 823                         map->cache_dirty = true;
 824                         return 0;
 825                 }
 826         }
 827
 828         ret = _regmap_select_page(map, &reg, val_len / map->format.val_bytes);
 829         if (ret < 0)
 830                 return ret;
 831
 832         map->format.format_reg(map->work_buf, reg, map->reg_shift);
 833
 834         u8[0] |= map->write_flag_mask;
 835
 836         trace_regmap_hw_write_start(map->dev, reg,
 837                                     val_len / map->format.val_bytes);
 838
 839         /* If we're doing a single register write we can probably just
 840          * send the work_buf directly, otherwise try to do a gather
 841          * write.
 842          */
 843         if (val == (map->work_buf + map->format.pad_bytes +
 844                     map->format.reg_bytes))
 845                 ret = map->bus->write(map->bus_context, map->work_buf,
 846                                       map->format.reg_bytes +
 847                                       map->format.pad_bytes +
 848                                       val_len);
 849         else if (map->bus->gather_write)
 850                 ret = map->bus->gather_write(map->bus_context, map->work_buf,
 851                                              map->format.reg_bytes +
 852                                              map->format.pad_bytes,
 853                                              val, val_len);
 854
 855         /* If that didn't work fall back on linearising by hand. */
 856         if (ret == -ENOTSUPP) {
 857                 len = map->format.reg_bytes + map->format.pad_bytes + val_len;
 858                 buf = kzalloc(len, GFP_KERNEL);
 859                 if (!buf)
 860                         return -ENOMEM;
 861
 862                 memcpy(buf, map->work_buf, map->format.reg_bytes);
 863                 memcpy(buf + map->format.reg_bytes + map->format.pad_bytes,
 864                        val, val_len);
 865                 ret = map->bus->write(map->bus_context, buf, len);
 866
 867                 kfree(buf);
 868         }
 869
 870         trace_regmap_hw_write_done(map->dev, reg,
 871                                    val_len / map->format.val_bytes);
 872
 873         return ret;
 874 }
 875
 876 int _regmap_write(struct regmap *map, unsigned int reg,
 877                   unsigned int val)
 878 {
 879         int ret;
 880         BUG_ON(!map->format.format_write && !map->format.format_val);
 881
 882         if (!map->cache_bypass && map->format.format_write) {
 883                 ret = regcache_write(map, reg, val);
 884                 if (ret != 0)
 885                         return ret;
 886                 if (map->cache_only) {
 887                         map->cache_dirty = true;
 888                         return 0;
 889                 }
 890         }
 891
 892 #ifdef LOG_DEVICE
 893         if (strcmp(dev_name(map->dev), LOG_DEVICE) == 0)
 894                 dev_info(map->dev, "%x <= %x\n", reg, val);
 895 #endif
 896
 897         trace_regmap_reg_write(map->dev, reg, val);
 898
 899         if (map->format.format_write) {
 900                 ret = _regmap_select_page(map, &reg, 1);
 901                 if (ret < 0)
 902                         return ret;
 903
 904                 map->format.format_write(map, reg, val);
 905
 906                 trace_regmap_hw_write_start(map->dev, reg, 1);
 907
 908                 ret = map->bus->write(map->bus_context, map->work_buf,
 909                                       map->format.buf_size);
 910
 911                 trace_regmap_hw_write_done(map->dev, reg, 1);
 912
 913                 return ret;
 914         } else {
 915                 map->format.format_val(map->work_buf + map->format.reg_bytes
 916                                        + map->format.pad_bytes, val, 0);
 917                 return _regmap_raw_write(map, reg,
 918                                          map->work_buf +
 919                                          map->format.reg_bytes +
 920                                          map->format.pad_bytes,
 921                                          map->format.val_bytes);
 922         }
 923 }
 924
 925 /**
 926  * regmap_write(): Write a value to a single register
 927  *
 928  * @map: Register map to write to
 929  * @reg: Register to write to
 930  * @val: Value to be written
 931  *
 932  * A value of zero will be returned on success, a negative errno will
 933  * be returned in error cases.
 934  */
 935 int regmap_write(struct regmap *map, unsigned int reg, unsigned int val)
 936 {
 937         int ret;
 938
 939         if (reg % map->reg_stride)
 940                 return -EINVAL;
 941
 942         map->lock(map);
 943
 944         ret = _regmap_write(map, reg, val);
 945
 946         map->unlock(map);
 947
 948         return ret;
 949 }
 950 EXPORT_SYMBOL_GPL(regmap_write);
 951
 952 /**
 953  * regmap_raw_write(): Write raw values to one or more registers
 954  *
 955  * @map: Register map to write to
 956  * @reg: Initial register to write to
 957  * @val: Block of data to be written, laid out for direct transmission to the
 958  *       device
 959  * @val_len: Length of data pointed to by val.
 960  *
 961  * This function is intended to be used for things like firmware
 962  * download where a large block of data needs to be transferred to the
 963  * device.  No formatting will be done on the data provided.
 964  *
 965  * A value of zero will be returned on success, a negative errno will
 966  * be returned in error cases.
 967  */
 968 int regmap_raw_write(struct regmap *map, unsigned int reg,
 969                      const void *val, size_t val_len)
 970 {
 971         int ret;
 972
 973         if (val_len % map->format.val_bytes)
 974                 return -EINVAL;
 975         if (reg % map->reg_stride)
 976                 return -EINVAL;
 977
 978         map->lock(map);
 979
 980         ret = _regmap_raw_write(map, reg, val, val_len);
 981
 982         map->unlock(map);
 983
 984         return ret;
 985 }
 986 EXPORT_SYMBOL_GPL(regmap_raw_write);
 987
 988 /*
 989  * regmap_bulk_write(): Write multiple registers to the device
 990  *
 991  * @map: Register map to write to
 992  * @reg: First register to be write from
 993  * @val: Block of data to be written, in native register size for device
 994  * @val_count: Number of registers to write
 995  *
 996  * This function is intended to be used for writing a large block of
 997  * data to be device either in single transfer or multiple transfer.
 998  *
 999  * A value of zero will be returned on success, a negative errno will
1000  * be returned in error cases.
1001  */
1002 int regmap_bulk_write(struct regmap *map, unsigned int reg, const void *val,
1003                      size_t val_count)
1004 {
1005         int ret = 0, i;
1006         size_t val_bytes = map->format.val_bytes;
1007         void *wval;
1008
1009         if (!map->format.parse_val)
1010                 return -EINVAL;
1011         if (reg % map->reg_stride)
1012                 return -EINVAL;
1013
1014         map->lock(map);
1015
1016         /* No formatting is require if val_byte is 1 */
1017         if (val_bytes == 1) {
1018                 wval = (void *)val;
1019         } else {
1020                 wval = kmemdup(val, val_count * val_bytes, GFP_KERNEL);
1021                 if (!wval) {
1022                         ret = -ENOMEM;
1023                         dev_err(map->dev, "Error in memory allocation\n");
1024                         goto out;
1025                 }
1026                 for (i = 0; i < val_count * val_bytes; i += val_bytes)
1027                         map->format.parse_val(wval + i);
1028         }
1029         /*
1030          * Some devices does not support bulk write, for
1031          * them we have a series of single write operations.
1032          */
1033         if (map->use_single_rw) {
1034                 for (i = 0; i < val_count; i++) {
1035                         ret = regmap_raw_write(map,
1036                                                 reg + (i * map->reg_stride),
1037                                                 val + (i * val_bytes),
1038                                                 val_bytes);
1039                         if (ret != 0)
1040                                 return ret;
1041                 }
1042         } else {
1043                 ret = _regmap_raw_write(map, reg, wval, val_bytes * val_count);
1044         }
1045
1046         if (val_bytes != 1)
1047                 kfree(wval);
1048
1049 out:
1050         map->unlock(map);
1051         return ret;
1052 }
1053 EXPORT_SYMBOL_GPL(regmap_bulk_write);
1054
1055 static int _regmap_raw_read(struct regmap *map, unsigned int reg, void *val,
1056                             unsigned int val_len)
1057 {
1058         u8 *u8 = map->work_buf;
1059         int ret;
1060
1061         ret = _regmap_select_page(map, &reg, val_len / map->format.val_bytes);
1062         if (ret < 0)
1063                 return ret;
1064
1065         map->format.format_reg(map->work_buf, reg, map->reg_shift);
1066
1067         /*
1068          * Some buses or devices flag reads by setting the high bits in the
1069          * register addresss; since it's always the high bits for all
1070          * current formats we can do this here rather than in
1071          * formatting.  This may break if we get interesting formats.
1072          */
1073         u8[0] |= map->read_flag_mask;
1074
1075         trace_regmap_hw_read_start(map->dev, reg,
1076                                    val_len / map->format.val_bytes);
1077
1078         ret = map->bus->read(map->bus_context, map->work_buf,
1079                              map->format.reg_bytes + map->format.pad_bytes,
1080                              val, val_len);
1081
1082         trace_regmap_hw_read_done(map->dev, reg,
1083                                   val_len / map->format.val_bytes);
1084
1085         return ret;
1086 }
1087
1088 static int _regmap_read(struct regmap *map, unsigned int reg,
1089                         unsigned int *val)
1090 {
1091         int ret;
1092
1093         if (!map->cache_bypass) {
1094                 ret = regcache_read(map, reg, val);
1095                 if (ret == 0)
1096                         return 0;
1097         }
1098
1099         if (!map->format.parse_val)
1100                 return -EINVAL;
1101
1102         if (map->cache_only)
1103                 return -EBUSY;
1104
1105         ret = _regmap_raw_read(map, reg, map->work_buf, map->format.val_bytes);
1106         if (ret == 0) {
1107                 *val = map->format.parse_val(map->work_buf);
1108
1109 #ifdef LOG_DEVICE
1110                 if (strcmp(dev_name(map->dev), LOG_DEVICE) == 0)
1111                         dev_info(map->dev, "%x => %x\n", reg, *val);
1112 #endif
1113
1114                 trace_regmap_reg_read(map->dev, reg, *val);
1115         }
1116
1117         if (ret == 0 && !map->cache_bypass)
1118                 regcache_write(map, reg, *val);
1119
1120         return ret;
1121 }
1122
1123 /**
1124  * regmap_read(): Read a value from a single register
1125  *
1126  * @map: Register map to write to
1127  * @reg: Register to be read from
1128  * @val: Pointer to store read value
1129  *
1130  * A value of zero will be returned on success, a negative errno will
1131  * be returned in error cases.
1132  */
1133 int regmap_read(struct regmap *map, unsigned int reg, unsigned int *val)
1134 {
1135         int ret;
1136
1137         if (reg % map->reg_stride)
1138                 return -EINVAL;
1139
1140         map->lock(map);
1141
1142         ret = _regmap_read(map, reg, val);
1143
1144         map->unlock(map);
1145
1146         return ret;
1147 }
1148 EXPORT_SYMBOL_GPL(regmap_read);
1149
1150 /**
1151  * regmap_raw_read(): Read raw data from the device
1152  *
1153  * @map: Register map to write to
1154  * @reg: First register to be read from
1155  * @val: Pointer to store read value
1156  * @val_len: Size of data to read
1157  *
1158  * A value of zero will be returned on success, a negative errno will
1159  * be returned in error cases.
1160  */
1161 int regmap_raw_read(struct regmap *map, unsigned int reg, void *val,
1162                     size_t val_len)
1163 {
1164         size_t val_bytes = map->format.val_bytes;
1165         size_t val_count = val_len / val_bytes;
1166         unsigned int v;
1167         int ret, i;
1168
1169         if (val_len % map->format.val_bytes)
1170                 return -EINVAL;
1171         if (reg % map->reg_stride)
1172                 return -EINVAL;
1173
1174         map->lock(map);
1175
1176         if (regmap_volatile_range(map, reg, val_count) || map->cache_bypass ||
1177             map->cache_type == REGCACHE_NONE) {
1178                 /* Physical block read if there's no cache involved */
1179                 ret = _regmap_raw_read(map, reg, val, val_len);
1180
1181         } else {
1182                 /* Otherwise go word by word for the cache; should be low
1183                  * cost as we expect to hit the cache.
1184                  */
1185                 for (i = 0; i < val_count; i++) {
1186                         ret = _regmap_read(map, reg + (i * map->reg_stride),
1187                                            &v);
1188                         if (ret != 0)
1189                                 goto out;
1190
1191                         map->format.format_val(val + (i * val_bytes), v, 0);
1192                 }
1193         }
1194
1195  out:
1196         map->unlock(map);
1197
1198         return ret;
1199 }
1200 EXPORT_SYMBOL_GPL(regmap_raw_read);
1201
1202 /**
1203  * regmap_bulk_read(): Read multiple registers from the device
1204  *
1205  * @map: Register map to write to
1206  * @reg: First register to be read from
1207  * @val: Pointer to store read value, in native register size for device
1208  * @val_count: Number of registers to read
1209  *
1210  * A value of zero will be returned on success, a negative errno will
1211  * be returned in error cases.
1212  */
1213 int regmap_bulk_read(struct regmap *map, unsigned int reg, void *val,
1214                      size_t val_count)
1215 {
1216         int ret, i;
1217         size_t val_bytes = map->format.val_bytes;
1218         bool vol = regmap_volatile_range(map, reg, val_count);
1219
1220         if (!map->format.parse_val)
1221                 return -EINVAL;
1222         if (reg % map->reg_stride)
1223                 return -EINVAL;
1224
1225         if (vol || map->cache_type == REGCACHE_NONE) {
1226                 /*
1227                  * Some devices does not support bulk read, for
1228                  * them we have a series of single read operations.
1229                  */
1230                 if (map->use_single_rw) {
1231                         for (i = 0; i < val_count; i++) {
1232                                 ret = regmap_raw_read(map,
1233                                                 reg + (i * map->reg_stride),
1234                                                 val + (i * val_bytes),
1235                                                 val_bytes);
1236                                 if (ret != 0)
1237                                         return ret;
1238                         }
1239                 } else {
1240                         ret = regmap_raw_read(map, reg, val,
1241                                               val_bytes * val_count);
1242                         if (ret != 0)
1243                                 return ret;
1244                 }
1245
1246                 for (i = 0; i < val_count * val_bytes; i += val_bytes)
1247                         map->format.parse_val(val + i);
1248         } else {
1249                 for (i = 0; i < val_count; i++) {
1250                         unsigned int ival;
1251                         ret = regmap_read(map, reg + (i * map->reg_stride),
1252                                           &ival);
1253                         if (ret != 0)
1254                                 return ret;
1255                         memcpy(val + (i * val_bytes), &ival, val_bytes);
1256                 }
1257         }
1258
1259         return 0;
1260 }
1261 EXPORT_SYMBOL_GPL(regmap_bulk_read);
1262
1263 static int _regmap_update_bits(struct regmap *map, unsigned int reg,
1264                                unsigned int mask, unsigned int val,
1265                                bool *change)
1266 {
1267         int ret;
1268         unsigned int tmp, orig;
1269
1270         ret = _regmap_read(map, reg, &orig);
1271         if (ret != 0)
1272                 return ret;
1273
1274         tmp = orig & ~mask;
1275         tmp |= val & mask;
1276
1277         if (tmp != orig) {
1278                 ret = _regmap_write(map, reg, tmp);
1279                 *change = true;
1280         } else {
1281                 *change = false;
1282         }
1283
1284         return ret;
1285 }
1286
1287 /**
1288  * regmap_update_bits: Perform a read/modify/write cycle on the register map
1289  *
1290  * @map: Register map to update
1291  * @reg: Register to update
1292  * @mask: Bitmask to change
1293  * @val: New value for bitmask
1294  *
1295  * Returns zero for success, a negative number on error.
1296  */
1297 int regmap_update_bits(struct regmap *map, unsigned int reg,
1298                        unsigned int mask, unsigned int val)
1299 {
1300         bool change;
1301         int ret;
1302
1303         map->lock(map);
1304         ret = _regmap_update_bits(map, reg, mask, val, &change);
1305         map->unlock(map);
1306
1307         return ret;
1308 }
1309 EXPORT_SYMBOL_GPL(regmap_update_bits);
1310
1311 /**
1312  * regmap_update_bits_check: Perform a read/modify/write cycle on the
1313  *                           register map and report if updated
1314  *
1315  * @map: Register map to update
1316  * @reg: Register to update
1317  * @mask: Bitmask to change
1318  * @val: New value for bitmask
1319  * @change: Boolean indicating if a write was done
1320  *
1321  * Returns zero for success, a negative number on error.
1322  */
1323 int regmap_update_bits_check(struct regmap *map, unsigned int reg,
1324                              unsigned int mask, unsigned int val,
1325                              bool *change)
1326 {
1327         int ret;
1328
1329         map->lock(map);
1330         ret = _regmap_update_bits(map, reg, mask, val, change);
1331         map->unlock(map);
1332         return ret;
1333 }
1334 EXPORT_SYMBOL_GPL(regmap_update_bits_check);
1335
1336 /**
1337  * regmap_register_patch: Register and apply register updates to be applied
1338  *                        on device initialistion
1339  *
1340  * @map: Register map to apply updates to.
1341  * @regs: Values to update.
1342  * @num_regs: Number of entries in regs.
1343  *
1344  * Register a set of register updates to be applied to the device
1345  * whenever the device registers are synchronised with the cache and
1346  * apply them immediately.  Typically this is used to apply
1347  * corrections to be applied to the device defaults on startup, such
1348  * as the updates some vendors provide to undocumented registers.
1349  */
1350 int regmap_register_patch(struct regmap *map, const struct reg_default *regs,
1351                           int num_regs)
1352 {
1353         int i, ret;
1354         bool bypass;
1355
1356         /* If needed the implementation can be extended to support this */
1357         if (map->patch)
1358                 return -EBUSY;
1359
1360         map->lock(map);
1361
1362         bypass = map->cache_bypass;
1363
1364         map->cache_bypass = true;
1365
1366         /* Write out first; it's useful to apply even if we fail later. */
1367         for (i = 0; i < num_regs; i++) {
1368                 ret = _regmap_write(map, regs[i].reg, regs[i].def);
1369                 if (ret != 0) {
1370                         dev_err(map->dev, "Failed to write %x = %x: %d\n",
1371                                 regs[i].reg, regs[i].def, ret);
1372                         goto out;
1373                 }
1374         }
1375
1376         map->patch = kcalloc(num_regs, sizeof(struct reg_default), GFP_KERNEL);
1377         if (map->patch != NULL) {
1378                 memcpy(map->patch, regs,
1379                        num_regs * sizeof(struct reg_default));
1380                 map->patch_regs = num_regs;
1381         } else {
1382                 ret = -ENOMEM;
1383         }
1384
1385 out:
1386         map->cache_bypass = bypass;
1387
1388         map->unlock(map);
1389
1390         return ret;
1391 }
1392 EXPORT_SYMBOL_GPL(regmap_register_patch);
1393
1394 /*
1395  * regmap_get_val_bytes(): Report the size of a register value
1396  *
1397  * Report the size of a register value, mainly intended to for use by
1398  * generic infrastructure built on top of regmap.
1399  */
1400 int regmap_get_val_bytes(struct regmap *map)
1401 {
1402         if (map->format.format_write)
1403                 return -EINVAL;
1404
1405         return map->format.val_bytes;
1406 }
1407 EXPORT_SYMBOL_GPL(regmap_get_val_bytes);
1408
1409 static int __init regmap_initcall(void)
1410 {
1411         regmap_debugfs_initcall();
1412
1413         return 0;
1414 }
1415 postcore_initcall(regmap_initcall);