sound/soc/soc-cache.c

   1 /*
   2  * soc-cache.c  --  ASoC register cache helpers
   3  *
   4  * Copyright 2009 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 it
   9  *  under  the terms of  the GNU General  Public License as published by the
  10  *  Free Software Foundation;  either version 2 of the  License, or (at your
  11  *  option) any later version.
  12  */
  13
  14 #include <linux/i2c.h>
  15 #include <linux/spi/spi.h>
  16 #include <sound/soc.h>
  17 #include <linux/lzo.h>
  18 #include <linux/bitmap.h>
  19 #include <linux/rbtree.h>
  20
  21 #include <trace/events/asoc.h>
  22
  23 #if defined(CONFIG_SPI_MASTER)
  24 static int do_spi_write(void *control_data, const void *msg,
  25                         int len)
  26 {
  27         struct spi_device *spi = control_data;
  28         struct spi_transfer t;
  29         struct spi_message m;
  30
  31         if (len <= 0)
  32                 return 0;
  33
  34         spi_message_init(&m);
  35         memset(&t, 0, sizeof t);
  36
  37         t.tx_buf = msg;
  38         t.len = len;
  39
  40         spi_message_add_tail(&t, &m);
  41         spi_sync(spi, &m);
  42
  43         return len;
  44 }
  45 #endif
  46
  47 static int do_hw_write(struct snd_soc_codec *codec, unsigned int reg,
  48                        unsigned int value, const void *data, int len)
  49 {
  50         int ret;
  51
  52         if (!snd_soc_codec_volatile_register(codec, reg) &&
  53             reg < codec->driver->reg_cache_size &&
  54             !codec->cache_bypass) {
  55                 ret = snd_soc_cache_write(codec, reg, value);
  56                 if (ret < 0)
  57                         return -1;
  58         }
  59
  60         if (codec->cache_only) {
  61                 codec->cache_sync = 1;
  62                 return 0;
  63         }
  64
  65         ret = codec->hw_write(codec->control_data, data, len);
  66         if (ret == len)
  67                 return 0;
  68         if (ret < 0)
  69                 return ret;
  70         else
  71                 return -EIO;
  72 }
  73
  74 static unsigned int do_hw_read(struct snd_soc_codec *codec, unsigned int reg)
  75 {
  76         int ret;
  77         unsigned int val;
  78
  79         if (reg >= codec->driver->reg_cache_size ||
  80             snd_soc_codec_volatile_register(codec, reg) ||
  81             codec->cache_bypass) {
  82                 if (codec->cache_only)
  83                         return -1;
  84
  85                 BUG_ON(!codec->hw_read);
  86                 return codec->hw_read(codec, reg);
  87         }
  88
  89         ret = snd_soc_cache_read(codec, reg, &val);
  90         if (ret < 0)
  91                 return -1;
  92         return val;
  93 }
  94
  95 static unsigned int snd_soc_4_12_read(struct snd_soc_codec *codec,
  96                                       unsigned int reg)
  97 {
  98         return do_hw_read(codec, reg);
  99 }
 100
 101 static int snd_soc_4_12_write(struct snd_soc_codec *codec, unsigned int reg,
 102                               unsigned int value)
 103 {
 104         u8 data[2];
 105
 106         data[0] = (reg << 4) | ((value >> 8) & 0x000f);
 107         data[1] = value & 0x00ff;
 108
 109         return do_hw_write(codec, reg, value, data, 2);
 110 }
 111
 112 #if defined(CONFIG_SPI_MASTER)
 113 static int snd_soc_4_12_spi_write(void *control_data, const char *data,
 114                                   int len)
 115 {
 116         u8 msg[2];
 117
 118         msg[0] = data[1];
 119         msg[1] = data[0];
 120
 121         return do_spi_write(control_data, msg, len);
 122 }
 123 #else
 124 #define snd_soc_4_12_spi_write NULL
 125 #endif
 126
 127 static unsigned int snd_soc_7_9_read(struct snd_soc_codec *codec,
 128                                      unsigned int reg)
 129 {
 130         return do_hw_read(codec, reg);
 131 }
 132
 133 static int snd_soc_7_9_write(struct snd_soc_codec *codec, unsigned int reg,
 134                              unsigned int value)
 135 {
 136         u8 data[2];
 137
 138         data[0] = (reg << 1) | ((value >> 8) & 0x0001);
 139         data[1] = value & 0x00ff;
 140
 141         return do_hw_write(codec, reg, value, data, 2);
 142 }
 143
 144 #if defined(CONFIG_SPI_MASTER)
 145 static int snd_soc_7_9_spi_write(void *control_data, const char *data,
 146                                  int len)
 147 {
 148         u8 msg[2];
 149
 150         msg[0] = data[0];
 151         msg[1] = data[1];
 152
 153         return do_spi_write(control_data, msg, len);
 154 }
 155 #else
 156 #define snd_soc_7_9_spi_write NULL
 157 #endif
 158
 159 static int snd_soc_8_8_write(struct snd_soc_codec *codec, unsigned int reg,
 160                              unsigned int value)
 161 {
 162         u8 data[2];
 163
 164         reg &= 0xff;
 165         data[0] = reg;
 166         data[1] = value & 0xff;
 167
 168         return do_hw_write(codec, reg, value, data, 2);
 169 }
 170
 171 static unsigned int snd_soc_8_8_read(struct snd_soc_codec *codec,
 172                                      unsigned int reg)
 173 {
 174         return do_hw_read(codec, reg);
 175 }
 176
 177 #if defined(CONFIG_SPI_MASTER)
 178 static int snd_soc_8_8_spi_write(void *control_data, const char *data,
 179                                  int len)
 180 {
 181         u8 msg[2];
 182
 183         msg[0] = data[0];
 184         msg[1] = data[1];
 185
 186         return do_spi_write(control_data, msg, len);
 187 }
 188 #else
 189 #define snd_soc_8_8_spi_write NULL
 190 #endif
 191
 192 static int snd_soc_8_16_write(struct snd_soc_codec *codec, unsigned int reg,
 193                               unsigned int value)
 194 {
 195         u8 data[3];
 196
 197         data[0] = reg;
 198         data[1] = (value >> 8) & 0xff;
 199         data[2] = value & 0xff;
 200
 201         return do_hw_write(codec, reg, value, data, 3);
 202 }
 203
 204 static unsigned int snd_soc_8_16_read(struct snd_soc_codec *codec,
 205                                       unsigned int reg)
 206 {
 207         return do_hw_read(codec, reg);
 208 }
 209
 210 #if defined(CONFIG_SPI_MASTER)
 211 static int snd_soc_8_16_spi_write(void *control_data, const char *data,
 212                                   int len)
 213 {
 214         u8 msg[3];
 215
 216         msg[0] = data[0];
 217         msg[1] = data[1];
 218         msg[2] = data[2];
 219
 220         return do_spi_write(control_data, msg, len);
 221 }
 222 #else
 223 #define snd_soc_8_16_spi_write NULL
 224 #endif
 225
 226 #if defined(CONFIG_I2C) || (defined(CONFIG_I2C_MODULE) && defined(MODULE))
 227 static unsigned int do_i2c_read(struct snd_soc_codec *codec,
 228                                 void *reg, int reglen,
 229                                 void *data, int datalen)
 230 {
 231         struct i2c_msg xfer[2];
 232         int ret;
 233         struct i2c_client *client = codec->control_data;
 234
 235         /* Write register */
 236         xfer[0].addr = client->addr;
 237         xfer[0].flags = 0;
 238         xfer[0].len = reglen;
 239         xfer[0].buf = reg;
 240
 241         /* Read data */
 242         xfer[1].addr = client->addr;
 243         xfer[1].flags = I2C_M_RD;
 244         xfer[1].len = datalen;
 245         xfer[1].buf = data;
 246
 247         ret = i2c_transfer(client->adapter, xfer, 2);
 248         if (ret == 2)
 249                 return 0;
 250         else if (ret < 0)
 251                 return ret;
 252         else
 253                 return -EIO;
 254 }
 255 #endif
 256
 257 #if defined(CONFIG_I2C) || (defined(CONFIG_I2C_MODULE) && defined(MODULE))
 258 static unsigned int snd_soc_8_8_read_i2c(struct snd_soc_codec *codec,
 259                                          unsigned int r)
 260 {
 261         u8 reg = r;
 262         u8 data;
 263         int ret;
 264
 265         ret = do_i2c_read(codec, &reg, 1, &data, 1);
 266         if (ret < 0)
 267                 return 0;
 268         return data;
 269 }
 270 #else
 271 #define snd_soc_8_8_read_i2c NULL
 272 #endif
 273
 274 #if defined(CONFIG_I2C) || (defined(CONFIG_I2C_MODULE) && defined(MODULE))
 275 static unsigned int snd_soc_8_16_read_i2c(struct snd_soc_codec *codec,
 276                                           unsigned int r)
 277 {
 278         u8 reg = r;
 279         u16 data;
 280         int ret;
 281
 282         ret = do_i2c_read(codec, &reg, 1, &data, 2);
 283         if (ret < 0)
 284                 return 0;
 285         return (data >> 8) | ((data & 0xff) << 8);
 286 }
 287 #else
 288 #define snd_soc_8_16_read_i2c NULL
 289 #endif
 290
 291 #if defined(CONFIG_I2C) || (defined(CONFIG_I2C_MODULE) && defined(MODULE))
 292 static unsigned int snd_soc_16_8_read_i2c(struct snd_soc_codec *codec,
 293                                           unsigned int r)
 294 {
 295         u16 reg = r;
 296         u8 data;
 297         int ret;
 298
 299         ret = do_i2c_read(codec, &reg, 2, &data, 1);
 300         if (ret < 0)
 301                 return 0;
 302         return data;
 303 }
 304 #else
 305 #define snd_soc_16_8_read_i2c NULL
 306 #endif
 307
 308 static unsigned int snd_soc_16_8_read(struct snd_soc_codec *codec,
 309                                       unsigned int reg)
 310 {
 311         return do_hw_read(codec, reg);
 312 }
 313
 314 static int snd_soc_16_8_write(struct snd_soc_codec *codec, unsigned int reg,
 315                               unsigned int value)
 316 {
 317         u8 data[3];
 318
 319         data[0] = (reg >> 8) & 0xff;
 320         data[1] = reg & 0xff;
 321         data[2] = value;
 322         reg &= 0xff;
 323
 324         return do_hw_write(codec, reg, value, data, 3);
 325 }
 326
 327 #if defined(CONFIG_SPI_MASTER)
 328 static int snd_soc_16_8_spi_write(void *control_data, const char *data,
 329                                   int len)
 330 {
 331         u8 msg[3];
 332
 333         msg[0] = data[0];
 334         msg[1] = data[1];
 335         msg[2] = data[2];
 336
 337         return do_spi_write(control_data, msg, len);
 338 }
 339 #else
 340 #define snd_soc_16_8_spi_write NULL
 341 #endif
 342
 343 #if defined(CONFIG_I2C) || (defined(CONFIG_I2C_MODULE) && defined(MODULE))
 344 static unsigned int snd_soc_16_16_read_i2c(struct snd_soc_codec *codec,
 345                                            unsigned int r)
 346 {
 347         u16 reg = cpu_to_be16(r);
 348         u16 data;
 349         int ret;
 350
 351         ret = do_i2c_read(codec, &reg, 2, &data, 2);
 352         if (ret < 0)
 353                 return 0;
 354         return be16_to_cpu(data);
 355 }
 356 #else
 357 #define snd_soc_16_16_read_i2c NULL
 358 #endif
 359
 360 static unsigned int snd_soc_16_16_read(struct snd_soc_codec *codec,
 361                                        unsigned int reg)
 362 {
 363         return do_hw_read(codec, reg);
 364 }
 365
 366 static int snd_soc_16_16_write(struct snd_soc_codec *codec, unsigned int reg,
 367                                unsigned int value)
 368 {
 369         u8 data[4];
 370
 371         data[0] = (reg >> 8) & 0xff;
 372         data[1] = reg & 0xff;
 373         data[2] = (value >> 8) & 0xff;
 374         data[3] = value & 0xff;
 375
 376         return do_hw_write(codec, reg, value, data, 4);
 377 }
 378
 379 #if defined(CONFIG_SPI_MASTER)
 380 static int snd_soc_16_16_spi_write(void *control_data, const char *data,
 381                                    int len)
 382 {
 383         u8 msg[4];
 384
 385         msg[0] = data[0];
 386         msg[1] = data[1];
 387         msg[2] = data[2];
 388         msg[3] = data[3];
 389
 390         return do_spi_write(control_data, msg, len);
 391 }
 392 #else
 393 #define snd_soc_16_16_spi_write NULL
 394 #endif
 395
 396 /* Primitive bulk write support for soc-cache.  The data pointed to by
 397  * `data' needs to already be in the form the hardware expects
 398  * including any leading register specific data.  Any data written
 399  * through this function will not go through the cache as it only
 400  * handles writing to volatile or out of bounds registers.
 401  */
 402 static int snd_soc_hw_bulk_write_raw(struct snd_soc_codec *codec, unsigned int reg,
 403                                      const void *data, size_t len)
 404 {
 405         int ret;
 406
 407         /* To ensure that we don't get out of sync with the cache, check
 408          * whether the base register is volatile or if we've directly asked
 409          * to bypass the cache.  Out of bounds registers are considered
 410          * volatile.
 411          */
 412         if (!codec->cache_bypass
 413             && !snd_soc_codec_volatile_register(codec, reg)
 414             && reg < codec->driver->reg_cache_size)
 415                 return -EINVAL;
 416
 417         switch (codec->control_type) {
 418 #if defined(CONFIG_I2C) || (defined(CONFIG_I2C_MODULE) && defined(MODULE))
 419         case SND_SOC_I2C:
 420                 ret = i2c_master_send(codec->control_data, data, len);
 421                 break;
 422 #endif
 423 #if defined(CONFIG_SPI_MASTER)
 424         case SND_SOC_SPI:
 425                 ret = do_spi_write(codec->control_data, data, len);
 426                 break;
 427 #endif
 428         default:
 429                 BUG();
 430         }
 431
 432         if (ret == len)
 433                 return 0;
 434         if (ret < 0)
 435                 return ret;
 436         else
 437                 return -EIO;
 438 }
 439
 440 static struct {
 441         int addr_bits;
 442         int data_bits;
 443         int (*write)(struct snd_soc_codec *codec, unsigned int, unsigned int);
 444         int (*spi_write)(void *, const char *, int);
 445         unsigned int (*read)(struct snd_soc_codec *, unsigned int);
 446         unsigned int (*i2c_read)(struct snd_soc_codec *, unsigned int);
 447 } io_types[] = {
 448         {
 449                 .addr_bits = 4, .data_bits = 12,
 450                 .write = snd_soc_4_12_write, .read = snd_soc_4_12_read,
 451                 .spi_write = snd_soc_4_12_spi_write,
 452         },
 453         {
 454                 .addr_bits = 7, .data_bits = 9,
 455                 .write = snd_soc_7_9_write, .read = snd_soc_7_9_read,
 456                 .spi_write = snd_soc_7_9_spi_write,
 457         },
 458         {
 459                 .addr_bits = 8, .data_bits = 8,
 460                 .write = snd_soc_8_8_write, .read = snd_soc_8_8_read,
 461                 .i2c_read = snd_soc_8_8_read_i2c,
 462                 .spi_write = snd_soc_8_8_spi_write,
 463         },
 464         {
 465                 .addr_bits = 8, .data_bits = 16,
 466                 .write = snd_soc_8_16_write, .read = snd_soc_8_16_read,
 467                 .i2c_read = snd_soc_8_16_read_i2c,
 468                 .spi_write = snd_soc_8_16_spi_write,
 469         },
 470         {
 471                 .addr_bits = 16, .data_bits = 8,
 472                 .write = snd_soc_16_8_write, .read = snd_soc_16_8_read,
 473                 .i2c_read = snd_soc_16_8_read_i2c,
 474                 .spi_write = snd_soc_16_8_spi_write,
 475         },
 476         {
 477                 .addr_bits = 16, .data_bits = 16,
 478                 .write = snd_soc_16_16_write, .read = snd_soc_16_16_read,
 479                 .i2c_read = snd_soc_16_16_read_i2c,
 480                 .spi_write = snd_soc_16_16_spi_write,
 481         },
 482 };
 483
 484 /**
 485  * snd_soc_codec_set_cache_io: Set up standard I/O functions.
 486  *
 487  * @codec: CODEC to configure.
 488  * @addr_bits: Number of bits of register address data.
 489  * @data_bits: Number of bits of data per register.
 490  * @control: Control bus used.
 491  *
 492  * Register formats are frequently shared between many I2C and SPI
 493  * devices.  In order to promote code reuse the ASoC core provides
 494  * some standard implementations of CODEC read and write operations
 495  * which can be set up using this function.
 496  *
 497  * The caller is responsible for allocating and initialising the
 498  * actual cache.
 499  *
 500  * Note that at present this code cannot be used by CODECs with
 501  * volatile registers.
 502  */
 503 int snd_soc_codec_set_cache_io(struct snd_soc_codec *codec,
 504                                int addr_bits, int data_bits,
 505                                enum snd_soc_control_type control)
 506 {
 507         int i;
 508
 509         for (i = 0; i < ARRAY_SIZE(io_types); i++)
 510                 if (io_types[i].addr_bits == addr_bits &&
 511                     io_types[i].data_bits == data_bits)
 512                         break;
 513         if (i == ARRAY_SIZE(io_types)) {
 514                 printk(KERN_ERR
 515                        "No I/O functions for %d bit address %d bit data\n",
 516                        addr_bits, data_bits);
 517                 return -EINVAL;
 518         }
 519
 520         codec->write = io_types[i].write;
 521         codec->read = io_types[i].read;
 522         codec->bulk_write_raw = snd_soc_hw_bulk_write_raw;
 523
 524         switch (control) {
 525         case SND_SOC_CUSTOM:
 526                 break;
 527
 528         case SND_SOC_I2C:
 529 #if defined(CONFIG_I2C) || (defined(CONFIG_I2C_MODULE) && defined(MODULE))
 530                 codec->hw_write = (hw_write_t)i2c_master_send;
 531 #endif
 532                 if (io_types[i].i2c_read)
 533                         codec->hw_read = io_types[i].i2c_read;
 534
 535                 codec->control_data = container_of(codec->dev,
 536                                                    struct i2c_client,
 537                                                    dev);
 538                 break;
 539
 540         case SND_SOC_SPI:
 541                 if (io_types[i].spi_write)
 542                         codec->hw_write = io_types[i].spi_write;
 543
 544                 codec->control_data = container_of(codec->dev,
 545                                                    struct spi_device,
 546                                                    dev);
 547                 break;
 548         }
 549
 550         return 0;
 551 }
 552 EXPORT_SYMBOL_GPL(snd_soc_codec_set_cache_io);
 553
 554 static bool snd_soc_set_cache_val(void *base, unsigned int idx,
 555                                   unsigned int val, unsigned int word_size)
 556 {
 557         switch (word_size) {
 558         case 1: {
 559                 u8 *cache = base;
 560                 if (cache[idx] == val)
 561                         return true;
 562                 cache[idx] = val;
 563                 break;
 564         }
 565         case 2: {
 566                 u16 *cache = base;
 567                 if (cache[idx] == val)
 568                         return true;
 569                 cache[idx] = val;
 570                 break;
 571         }
 572         default:
 573                 BUG();
 574         }
 575         return false;
 576 }
 577
 578 static unsigned int snd_soc_get_cache_val(const void *base, unsigned int idx,
 579                 unsigned int word_size)
 580 {
 581         switch (word_size) {
 582         case 1: {
 583                 const u8 *cache = base;
 584                 return cache[idx];
 585         }
 586         case 2: {
 587                 const u16 *cache = base;
 588                 return cache[idx];
 589         }
 590         default:
 591                 BUG();
 592         }
 593         /* unreachable */
 594         return -1;
 595 }
 596
 597 struct snd_soc_rbtree_node {
 598         struct rb_node node;
 599         unsigned int reg;
 600         unsigned int value;
 601         unsigned int defval;
 602 } __attribute__ ((packed));
 603
 604 struct snd_soc_rbtree_ctx {
 605         struct rb_root root;
 606 };
 607
 608 static struct snd_soc_rbtree_node *snd_soc_rbtree_lookup(
 609         struct rb_root *root, unsigned int reg)
 610 {
 611         struct rb_node *node;
 612         struct snd_soc_rbtree_node *rbnode;
 613
 614         node = root->rb_node;
 615         while (node) {
 616                 rbnode = container_of(node, struct snd_soc_rbtree_node, node);
 617                 if (rbnode->reg < reg)
 618                         node = node->rb_left;
 619                 else if (rbnode->reg > reg)
 620                         node = node->rb_right;
 621                 else
 622                         return rbnode;
 623         }
 624
 625         return NULL;
 626 }
 627
 628 static int snd_soc_rbtree_insert(struct rb_root *root,
 629                                  struct snd_soc_rbtree_node *rbnode)
 630 {
 631         struct rb_node **new, *parent;
 632         struct snd_soc_rbtree_node *rbnode_tmp;
 633
 634         parent = NULL;
 635         new = &root->rb_node;
 636         while (*new) {
 637                 rbnode_tmp = container_of(*new, struct snd_soc_rbtree_node,
 638                                           node);
 639                 parent = *new;
 640                 if (rbnode_tmp->reg < rbnode->reg)
 641                         new = &((*new)->rb_left);
 642                 else if (rbnode_tmp->reg > rbnode->reg)
 643                         new = &((*new)->rb_right);
 644                 else
 645                         return 0;
 646         }
 647
 648         /* insert the node into the rbtree */
 649         rb_link_node(&rbnode->node, parent, new);
 650         rb_insert_color(&rbnode->node, root);
 651
 652         return 1;
 653 }
 654
 655 static int snd_soc_rbtree_cache_sync(struct snd_soc_codec *codec)
 656 {
 657         struct snd_soc_rbtree_ctx *rbtree_ctx;
 658         struct rb_node *node;
 659         struct snd_soc_rbtree_node *rbnode;
 660         unsigned int val;
 661         int ret;
 662
 663         rbtree_ctx = codec->reg_cache;
 664         for (node = rb_first(&rbtree_ctx->root); node; node = rb_next(node)) {
 665                 rbnode = rb_entry(node, struct snd_soc_rbtree_node, node);
 666                 if (rbnode->value == rbnode->defval)
 667                         continue;
 668                 WARN_ON(codec->writable_register &&
 669                         codec->writable_register(codec, rbnode->reg));
 670                 ret = snd_soc_cache_read(codec, rbnode->reg, &val);
 671                 if (ret)
 672                         return ret;
 673                 codec->cache_bypass = 1;
 674                 ret = snd_soc_write(codec, rbnode->reg, val);
 675                 codec->cache_bypass = 0;
 676                 if (ret)
 677                         return ret;
 678                 dev_dbg(codec->dev, "Synced register %#x, value = %#x\n",
 679                         rbnode->reg, val);
 680         }
 681
 682         return 0;
 683 }
 684
 685 static int snd_soc_rbtree_cache_write(struct snd_soc_codec *codec,
 686                                       unsigned int reg, unsigned int value)
 687 {
 688         struct snd_soc_rbtree_ctx *rbtree_ctx;
 689         struct snd_soc_rbtree_node *rbnode;
 690
 691         rbtree_ctx = codec->reg_cache;
 692         rbnode = snd_soc_rbtree_lookup(&rbtree_ctx->root, reg);
 693         if (rbnode) {
 694                 if (rbnode->value == value)
 695                         return 0;
 696                 rbnode->value = value;
 697         } else {
 698                 /* bail out early, no need to create the rbnode yet */
 699                 if (!value)
 700                         return 0;
 701                 /*
 702                  * for uninitialized registers whose value is changed
 703                  * from the default zero, create an rbnode and insert
 704                  * it into the tree.
 705                  */
 706                 rbnode = kzalloc(sizeof *rbnode, GFP_KERNEL);
 707                 if (!rbnode)
 708                         return -ENOMEM;
 709                 rbnode->reg = reg;
 710                 rbnode->value = value;
 711                 snd_soc_rbtree_insert(&rbtree_ctx->root, rbnode);
 712         }
 713
 714         return 0;
 715 }
 716
 717 static int snd_soc_rbtree_cache_read(struct snd_soc_codec *codec,
 718                                      unsigned int reg, unsigned int *value)
 719 {
 720         struct snd_soc_rbtree_ctx *rbtree_ctx;
 721         struct snd_soc_rbtree_node *rbnode;
 722
 723         rbtree_ctx = codec->reg_cache;
 724         rbnode = snd_soc_rbtree_lookup(&rbtree_ctx->root, reg);
 725         if (rbnode) {
 726                 *value = rbnode->value;
 727         } else {
 728                 /* uninitialized registers default to 0 */
 729                 *value = 0;
 730         }
 731
 732         return 0;
 733 }
 734
 735 static int snd_soc_rbtree_cache_exit(struct snd_soc_codec *codec)
 736 {
 737         struct rb_node *next;
 738         struct snd_soc_rbtree_ctx *rbtree_ctx;
 739         struct snd_soc_rbtree_node *rbtree_node;
 740
 741         /* if we've already been called then just return */
 742         rbtree_ctx = codec->reg_cache;
 743         if (!rbtree_ctx)
 744                 return 0;
 745
 746         /* free up the rbtree */
 747         next = rb_first(&rbtree_ctx->root);
 748         while (next) {
 749                 rbtree_node = rb_entry(next, struct snd_soc_rbtree_node, node);
 750                 next = rb_next(&rbtree_node->node);
 751                 rb_erase(&rbtree_node->node, &rbtree_ctx->root);
 752                 kfree(rbtree_node);
 753         }
 754
 755         /* release the resources */
 756         kfree(codec->reg_cache);
 757         codec->reg_cache = NULL;
 758
 759         return 0;
 760 }
 761
 762 static int snd_soc_rbtree_cache_init(struct snd_soc_codec *codec)
 763 {
 764         struct snd_soc_rbtree_node *rbtree_node;
 765         struct snd_soc_rbtree_ctx *rbtree_ctx;
 766         unsigned int val;
 767         unsigned int word_size;
 768         int i;
 769         int ret;
 770
 771         codec->reg_cache = kmalloc(sizeof *rbtree_ctx, GFP_KERNEL);
 772         if (!codec->reg_cache)
 773                 return -ENOMEM;
 774
 775         rbtree_ctx = codec->reg_cache;
 776         rbtree_ctx->root = RB_ROOT;
 777
 778         if (!codec->reg_def_copy)
 779                 return 0;
 780
 781         /*
 782          * populate the rbtree with the initialized registers.  All other
 783          * registers will be inserted when they are first modified.
 784          */
 785         word_size = codec->driver->reg_word_size;
 786         for (i = 0; i < codec->driver->reg_cache_size; ++i) {
 787                 val = snd_soc_get_cache_val(codec->reg_def_copy, i, word_size);
 788                 if (!val)
 789                         continue;
 790                 rbtree_node = kzalloc(sizeof *rbtree_node, GFP_KERNEL);
 791                 if (!rbtree_node) {
 792                         ret = -ENOMEM;
 793                         snd_soc_cache_exit(codec);
 794                         break;
 795                 }
 796                 rbtree_node->reg = i;
 797                 rbtree_node->value = val;
 798                 rbtree_node->defval = val;
 799                 snd_soc_rbtree_insert(&rbtree_ctx->root, rbtree_node);
 800         }
 801
 802         return 0;
 803 }
 804
 805 #ifdef CONFIG_SND_SOC_CACHE_LZO
 806 struct snd_soc_lzo_ctx {
 807         void *wmem;
 808         void *dst;
 809         const void *src;
 810         size_t src_len;
 811         size_t dst_len;
 812         size_t decompressed_size;
 813         unsigned long *sync_bmp;
 814         int sync_bmp_nbits;
 815 };
 816
 817 #define LZO_BLOCK_NUM 8
 818 static int snd_soc_lzo_block_count(void)
 819 {
 820         return LZO_BLOCK_NUM;
 821 }
 822
 823 static int snd_soc_lzo_prepare(struct snd_soc_lzo_ctx *lzo_ctx)
 824 {
 825         lzo_ctx->wmem = kmalloc(LZO1X_MEM_COMPRESS, GFP_KERNEL);
 826         if (!lzo_ctx->wmem)
 827                 return -ENOMEM;
 828         return 0;
 829 }
 830
 831 static int snd_soc_lzo_compress(struct snd_soc_lzo_ctx *lzo_ctx)
 832 {
 833         size_t compress_size;
 834         int ret;
 835
 836         ret = lzo1x_1_compress(lzo_ctx->src, lzo_ctx->src_len,
 837                                lzo_ctx->dst, &compress_size, lzo_ctx->wmem);
 838         if (ret != LZO_E_OK || compress_size > lzo_ctx->dst_len)
 839                 return -EINVAL;
 840         lzo_ctx->dst_len = compress_size;
 841         return 0;
 842 }
 843
 844 static int snd_soc_lzo_decompress(struct snd_soc_lzo_ctx *lzo_ctx)
 845 {
 846         size_t dst_len;
 847         int ret;
 848
 849         dst_len = lzo_ctx->dst_len;
 850         ret = lzo1x_decompress_safe(lzo_ctx->src, lzo_ctx->src_len,
 851                                     lzo_ctx->dst, &dst_len);
 852         if (ret != LZO_E_OK || dst_len != lzo_ctx->dst_len)
 853                 return -EINVAL;
 854         return 0;
 855 }
 856
 857 static int snd_soc_lzo_compress_cache_block(struct snd_soc_codec *codec,
 858                 struct snd_soc_lzo_ctx *lzo_ctx)
 859 {
 860         int ret;
 861
 862         lzo_ctx->dst_len = lzo1x_worst_compress(PAGE_SIZE);
 863         lzo_ctx->dst = kmalloc(lzo_ctx->dst_len, GFP_KERNEL);
 864         if (!lzo_ctx->dst) {
 865                 lzo_ctx->dst_len = 0;
 866                 return -ENOMEM;
 867         }
 868
 869         ret = snd_soc_lzo_compress(lzo_ctx);
 870         if (ret < 0)
 871                 return ret;
 872         return 0;
 873 }
 874
 875 static int snd_soc_lzo_decompress_cache_block(struct snd_soc_codec *codec,
 876                 struct snd_soc_lzo_ctx *lzo_ctx)
 877 {
 878         int ret;
 879
 880         lzo_ctx->dst_len = lzo_ctx->decompressed_size;
 881         lzo_ctx->dst = kmalloc(lzo_ctx->dst_len, GFP_KERNEL);
 882         if (!lzo_ctx->dst) {
 883                 lzo_ctx->dst_len = 0;
 884                 return -ENOMEM;
 885         }
 886
 887         ret = snd_soc_lzo_decompress(lzo_ctx);
 888         if (ret < 0)
 889                 return ret;
 890         return 0;
 891 }
 892
 893 static inline int snd_soc_lzo_get_blkindex(struct snd_soc_codec *codec,
 894                 unsigned int reg)
 895 {
 896         const struct snd_soc_codec_driver *codec_drv;
 897
 898         codec_drv = codec->driver;
 899         return (reg * codec_drv->reg_word_size) /
 900                DIV_ROUND_UP(codec->reg_size, snd_soc_lzo_block_count());
 901 }
 902
 903 static inline int snd_soc_lzo_get_blkpos(struct snd_soc_codec *codec,
 904                 unsigned int reg)
 905 {
 906         const struct snd_soc_codec_driver *codec_drv;
 907
 908         codec_drv = codec->driver;
 909         return reg % (DIV_ROUND_UP(codec->reg_size, snd_soc_lzo_block_count()) /
 910                       codec_drv->reg_word_size);
 911 }
 912
 913 static inline int snd_soc_lzo_get_blksize(struct snd_soc_codec *codec)
 914 {
 915         const struct snd_soc_codec_driver *codec_drv;
 916
 917         codec_drv = codec->driver;
 918         return DIV_ROUND_UP(codec->reg_size, snd_soc_lzo_block_count());
 919 }
 920
 921 static int snd_soc_lzo_cache_sync(struct snd_soc_codec *codec)
 922 {
 923         struct snd_soc_lzo_ctx **lzo_blocks;
 924         unsigned int val;
 925         int i;
 926         int ret;
 927
 928         lzo_blocks = codec->reg_cache;
 929         for_each_set_bit(i, lzo_blocks[0]->sync_bmp, lzo_blocks[0]->sync_bmp_nbits) {
 930                 WARN_ON(codec->writable_register &&
 931                         codec->writable_register(codec, i));
 932                 ret = snd_soc_cache_read(codec, i, &val);
 933                 if (ret)
 934                         return ret;
 935                 codec->cache_bypass = 1;
 936                 ret = snd_soc_write(codec, i, val);
 937                 codec->cache_bypass = 0;
 938                 if (ret)
 939                         return ret;
 940                 dev_dbg(codec->dev, "Synced register %#x, value = %#x\n",
 941                         i, val);
 942         }
 943
 944         return 0;
 945 }
 946
 947 static int snd_soc_lzo_cache_write(struct snd_soc_codec *codec,
 948                                    unsigned int reg, unsigned int value)
 949 {
 950         struct snd_soc_lzo_ctx *lzo_block, **lzo_blocks;
 951         int ret, blkindex, blkpos;
 952         size_t blksize, tmp_dst_len;
 953         void *tmp_dst;
 954
 955         /* index of the compressed lzo block */
 956         blkindex = snd_soc_lzo_get_blkindex(codec, reg);
 957         /* register index within the decompressed block */
 958         blkpos = snd_soc_lzo_get_blkpos(codec, reg);
 959         /* size of the compressed block */
 960         blksize = snd_soc_lzo_get_blksize(codec);
 961         lzo_blocks = codec->reg_cache;
 962         lzo_block = lzo_blocks[blkindex];
 963
 964         /* save the pointer and length of the compressed block */
 965         tmp_dst = lzo_block->dst;
 966         tmp_dst_len = lzo_block->dst_len;
 967
 968         /* prepare the source to be the compressed block */
 969         lzo_block->src = lzo_block->dst;
 970         lzo_block->src_len = lzo_block->dst_len;
 971
 972         /* decompress the block */
 973         ret = snd_soc_lzo_decompress_cache_block(codec, lzo_block);
 974         if (ret < 0) {
 975                 kfree(lzo_block->dst);
 976                 goto out;
 977         }
 978
 979         /* write the new value to the cache */
 980         if (snd_soc_set_cache_val(lzo_block->dst, blkpos, value,
 981                                   codec->driver->reg_word_size)) {
 982                 kfree(lzo_block->dst);
 983                 goto out;
 984         }
 985
 986         /* prepare the source to be the decompressed block */
 987         lzo_block->src = lzo_block->dst;
 988         lzo_block->src_len = lzo_block->dst_len;
 989
 990         /* compress the block */
 991         ret = snd_soc_lzo_compress_cache_block(codec, lzo_block);
 992         if (ret < 0) {
 993                 kfree(lzo_block->dst);
 994                 kfree(lzo_block->src);
 995                 goto out;
 996         }
 997
 998         /* set the bit so we know we have to sync this register */
 999         set_bit(reg, lzo_block->sync_bmp);
1000         kfree(tmp_dst);
1001         kfree(lzo_block->src);
1002         return 0;
1003 out:
1004         lzo_block->dst = tmp_dst;
1005         lzo_block->dst_len = tmp_dst_len;
1006         return ret;
1007 }
1008
1009 static int snd_soc_lzo_cache_read(struct snd_soc_codec *codec,
1010                                   unsigned int reg, unsigned int *value)
1011 {
1012         struct snd_soc_lzo_ctx *lzo_block, **lzo_blocks;
1013         int ret, blkindex, blkpos;
1014         size_t blksize, tmp_dst_len;
1015         void *tmp_dst;
1016
1017         *value = 0;
1018         /* index of the compressed lzo block */
1019         blkindex = snd_soc_lzo_get_blkindex(codec, reg);
1020         /* register index within the decompressed block */
1021         blkpos = snd_soc_lzo_get_blkpos(codec, reg);
1022         /* size of the compressed block */
1023         blksize = snd_soc_lzo_get_blksize(codec);
1024         lzo_blocks = codec->reg_cache;
1025         lzo_block = lzo_blocks[blkindex];
1026
1027         /* save the pointer and length of the compressed block */
1028         tmp_dst = lzo_block->dst;
1029         tmp_dst_len = lzo_block->dst_len;
1030
1031         /* prepare the source to be the compressed block */
1032         lzo_block->src = lzo_block->dst;
1033         lzo_block->src_len = lzo_block->dst_len;
1034
1035         /* decompress the block */
1036         ret = snd_soc_lzo_decompress_cache_block(codec, lzo_block);
1037         if (ret >= 0)
1038                 /* fetch the value from the cache */
1039                 *value = snd_soc_get_cache_val(lzo_block->dst, blkpos,
1040                                                codec->driver->reg_word_size);
1041
1042         kfree(lzo_block->dst);
1043         /* restore the pointer and length of the compressed block */
1044         lzo_block->dst = tmp_dst;
1045         lzo_block->dst_len = tmp_dst_len;
1046         return 0;
1047 }
1048
1049 static int snd_soc_lzo_cache_exit(struct snd_soc_codec *codec)
1050 {
1051         struct snd_soc_lzo_ctx **lzo_blocks;
1052         int i, blkcount;
1053
1054         lzo_blocks = codec->reg_cache;
1055         if (!lzo_blocks)
1056                 return 0;
1057
1058         blkcount = snd_soc_lzo_block_count();
1059         /*
1060          * the pointer to the bitmap used for syncing the cache
1061          * is shared amongst all lzo_blocks.  Ensure it is freed
1062          * only once.
1063          */
1064         if (lzo_blocks[0])
1065                 kfree(lzo_blocks[0]->sync_bmp);
1066         for (i = 0; i < blkcount; ++i) {
1067                 if (lzo_blocks[i]) {
1068                         kfree(lzo_blocks[i]->wmem);
1069                         kfree(lzo_blocks[i]->dst);
1070                 }
1071                 /* each lzo_block is a pointer returned by kmalloc or NULL */
1072                 kfree(lzo_blocks[i]);
1073         }
1074         kfree(lzo_blocks);
1075         codec->reg_cache = NULL;
1076         return 0;
1077 }
1078
1079 static int snd_soc_lzo_cache_init(struct snd_soc_codec *codec)
1080 {
1081         struct snd_soc_lzo_ctx **lzo_blocks;
1082         size_t bmp_size;
1083         const struct snd_soc_codec_driver *codec_drv;
1084         int ret, tofree, i, blksize, blkcount;
1085         const char *p, *end;
1086         unsigned long *sync_bmp;
1087
1088         ret = 0;
1089         codec_drv = codec->driver;
1090
1091         /*
1092          * If we have not been given a default register cache
1093          * then allocate a dummy zero-ed out region, compress it
1094          * and remember to free it afterwards.
1095          */
1096         tofree = 0;
1097         if (!codec->reg_def_copy)
1098                 tofree = 1;
1099
1100         if (!codec->reg_def_copy) {
1101                 codec->reg_def_copy = kzalloc(codec->reg_size, GFP_KERNEL);
1102                 if (!codec->reg_def_copy)
1103                         return -ENOMEM;
1104         }
1105
1106         blkcount = snd_soc_lzo_block_count();
1107         codec->reg_cache = kzalloc(blkcount * sizeof *lzo_blocks,
1108                                    GFP_KERNEL);
1109         if (!codec->reg_cache) {
1110                 ret = -ENOMEM;
1111                 goto err_tofree;
1112         }
1113         lzo_blocks = codec->reg_cache;
1114
1115         /*
1116          * allocate a bitmap to be used when syncing the cache with
1117          * the hardware.  Each time a register is modified, the corresponding
1118          * bit is set in the bitmap, so we know that we have to sync
1119          * that register.
1120          */
1121         bmp_size = codec_drv->reg_cache_size;
1122         sync_bmp = kmalloc(BITS_TO_LONGS(bmp_size) * sizeof(long),
1123                            GFP_KERNEL);
1124         if (!sync_bmp) {
1125                 ret = -ENOMEM;
1126                 goto err;
1127         }
1128         bitmap_zero(sync_bmp, bmp_size);
1129
1130         /* allocate the lzo blocks and initialize them */
1131         for (i = 0; i < blkcount; ++i) {
1132                 lzo_blocks[i] = kzalloc(sizeof **lzo_blocks,
1133                                         GFP_KERNEL);
1134                 if (!lzo_blocks[i]) {
1135                         kfree(sync_bmp);
1136                         ret = -ENOMEM;
1137                         goto err;
1138                 }
1139                 lzo_blocks[i]->sync_bmp = sync_bmp;
1140                 lzo_blocks[i]->sync_bmp_nbits = bmp_size;
1141                 /* alloc the working space for the compressed block */
1142                 ret = snd_soc_lzo_prepare(lzo_blocks[i]);
1143                 if (ret < 0)
1144                         goto err;
1145         }
1146
1147         blksize = snd_soc_lzo_get_blksize(codec);
1148         p = codec->reg_def_copy;
1149         end = codec->reg_def_copy + codec->reg_size;
1150         /* compress the register map and fill the lzo blocks */
1151         for (i = 0; i < blkcount; ++i, p += blksize) {
1152                 lzo_blocks[i]->src = p;
1153                 if (p + blksize > end)
1154                         lzo_blocks[i]->src_len = end - p;
1155                 else
1156                         lzo_blocks[i]->src_len = blksize;
1157                 ret = snd_soc_lzo_compress_cache_block(codec,
1158                                                        lzo_blocks[i]);
1159                 if (ret < 0)
1160                         goto err;
1161                 lzo_blocks[i]->decompressed_size =
1162                         lzo_blocks[i]->src_len;
1163         }
1164
1165         if (tofree) {
1166                 kfree(codec->reg_def_copy);
1167                 codec->reg_def_copy = NULL;
1168         }
1169         return 0;
1170 err:
1171         snd_soc_cache_exit(codec);
1172 err_tofree:
1173         if (tofree) {
1174                 kfree(codec->reg_def_copy);
1175                 codec->reg_def_copy = NULL;
1176         }
1177         return ret;
1178 }
1179 #endif
1180
1181 static int snd_soc_flat_cache_sync(struct snd_soc_codec *codec)
1182 {
1183         int i;
1184         int ret;
1185         const struct snd_soc_codec_driver *codec_drv;
1186         unsigned int val;
1187
1188         codec_drv = codec->driver;
1189         for (i = 0; i < codec_drv->reg_cache_size; ++i) {
1190                 WARN_ON(codec->writable_register &&
1191                         codec->writable_register(codec, i));
1192                 ret = snd_soc_cache_read(codec, i, &val);
1193                 if (ret)
1194                         return ret;
1195                 if (codec->reg_def_copy)
1196                         if (snd_soc_get_cache_val(codec->reg_def_copy,
1197                                                   i, codec_drv->reg_word_size) == val)
1198                                 continue;
1199                 ret = snd_soc_write(codec, i, val);
1200                 if (ret)
1201                         return ret;
1202                 dev_dbg(codec->dev, "Synced register %#x, value = %#x\n",
1203                         i, val);
1204         }
1205         return 0;
1206 }
1207
1208 static int snd_soc_flat_cache_write(struct snd_soc_codec *codec,
1209                                     unsigned int reg, unsigned int value)
1210 {
1211         snd_soc_set_cache_val(codec->reg_cache, reg, value,
1212                               codec->driver->reg_word_size);
1213         return 0;
1214 }
1215
1216 static int snd_soc_flat_cache_read(struct snd_soc_codec *codec,
1217                                    unsigned int reg, unsigned int *value)
1218 {
1219         *value = snd_soc_get_cache_val(codec->reg_cache, reg,
1220                                        codec->driver->reg_word_size);
1221         return 0;
1222 }
1223
1224 static int snd_soc_flat_cache_exit(struct snd_soc_codec *codec)
1225 {
1226         if (!codec->reg_cache)
1227                 return 0;
1228         kfree(codec->reg_cache);
1229         codec->reg_cache = NULL;
1230         return 0;
1231 }
1232
1233 static int snd_soc_flat_cache_init(struct snd_soc_codec *codec)
1234 {
1235         const struct snd_soc_codec_driver *codec_drv;
1236
1237         codec_drv = codec->driver;
1238
1239         if (codec->reg_def_copy)
1240                 codec->reg_cache = kmemdup(codec->reg_def_copy,
1241                                            codec->reg_size, GFP_KERNEL);
1242         else
1243                 codec->reg_cache = kzalloc(codec->reg_size, GFP_KERNEL);
1244         if (!codec->reg_cache)
1245                 return -ENOMEM;
1246
1247         return 0;
1248 }
1249
1250 /* an array of all supported compression types */
1251 static const struct snd_soc_cache_ops cache_types[] = {
1252         /* Flat *must* be the first entry for fallback */
1253         {
1254                 .id = SND_SOC_FLAT_COMPRESSION,
1255                 .name = "flat",
1256                 .init = snd_soc_flat_cache_init,
1257                 .exit = snd_soc_flat_cache_exit,
1258                 .read = snd_soc_flat_cache_read,
1259                 .write = snd_soc_flat_cache_write,
1260                 .sync = snd_soc_flat_cache_sync
1261         },
1262 #ifdef CONFIG_SND_SOC_CACHE_LZO
1263         {
1264                 .id = SND_SOC_LZO_COMPRESSION,
1265                 .name = "LZO",
1266                 .init = snd_soc_lzo_cache_init,
1267                 .exit = snd_soc_lzo_cache_exit,
1268                 .read = snd_soc_lzo_cache_read,
1269                 .write = snd_soc_lzo_cache_write,
1270                 .sync = snd_soc_lzo_cache_sync
1271         },
1272 #endif
1273         {
1274                 .id = SND_SOC_RBTREE_COMPRESSION,
1275                 .name = "rbtree",
1276                 .init = snd_soc_rbtree_cache_init,
1277                 .exit = snd_soc_rbtree_cache_exit,
1278                 .read = snd_soc_rbtree_cache_read,
1279                 .write = snd_soc_rbtree_cache_write,
1280                 .sync = snd_soc_rbtree_cache_sync
1281         }
1282 };
1283
1284 int snd_soc_cache_init(struct snd_soc_codec *codec)
1285 {
1286         int i;
1287
1288         for (i = 0; i < ARRAY_SIZE(cache_types); ++i)
1289                 if (cache_types[i].id == codec->compress_type)
1290                         break;
1291
1292         /* Fall back to flat compression */
1293         if (i == ARRAY_SIZE(cache_types)) {
1294                 dev_warn(codec->dev, "Could not match compress type: %d\n",
1295                          codec->compress_type);
1296                 i = 0;
1297         }
1298
1299         mutex_init(&codec->cache_rw_mutex);
1300         codec->cache_ops = &cache_types[i];
1301
1302         if (codec->cache_ops->init) {
1303                 if (codec->cache_ops->name)
1304                         dev_dbg(codec->dev, "Initializing %s cache for %s codec\n",
1305                                 codec->cache_ops->name, codec->name);
1306                 return codec->cache_ops->init(codec);
1307         }
1308         return -ENOSYS;
1309 }
1310
1311 /*
1312  * NOTE: keep in mind that this function might be called
1313  * multiple times.
1314  */
1315 int snd_soc_cache_exit(struct snd_soc_codec *codec)
1316 {
1317         if (codec->cache_ops && codec->cache_ops->exit) {
1318                 if (codec->cache_ops->name)
1319                         dev_dbg(codec->dev, "Destroying %s cache for %s codec\n",
1320                                 codec->cache_ops->name, codec->name);
1321                 return codec->cache_ops->exit(codec);
1322         }
1323         return -ENOSYS;
1324 }
1325
1326 /**
1327  * snd_soc_cache_read: Fetch the value of a given register from the cache.
1328  *
1329  * @codec: CODEC to configure.
1330  * @reg: The register index.
1331  * @value: The value to be returned.
1332  */
1333 int snd_soc_cache_read(struct snd_soc_codec *codec,
1334                        unsigned int reg, unsigned int *value)
1335 {
1336         int ret;
1337
1338         mutex_lock(&codec->cache_rw_mutex);
1339
1340         if (value && codec->cache_ops && codec->cache_ops->read) {
1341                 ret = codec->cache_ops->read(codec, reg, value);
1342                 mutex_unlock(&codec->cache_rw_mutex);
1343                 return ret;
1344         }
1345
1346         mutex_unlock(&codec->cache_rw_mutex);
1347         return -ENOSYS;
1348 }
1349 EXPORT_SYMBOL_GPL(snd_soc_cache_read);
1350
1351 /**
1352  * snd_soc_cache_write: Set the value of a given register in the cache.
1353  *
1354  * @codec: CODEC to configure.
1355  * @reg: The register index.
1356  * @value: The new register value.
1357  */
1358 int snd_soc_cache_write(struct snd_soc_codec *codec,
1359                         unsigned int reg, unsigned int value)
1360 {
1361         int ret;
1362
1363         mutex_lock(&codec->cache_rw_mutex);
1364
1365         if (codec->cache_ops && codec->cache_ops->write) {
1366                 ret = codec->cache_ops->write(codec, reg, value);
1367                 mutex_unlock(&codec->cache_rw_mutex);
1368                 return ret;
1369         }
1370
1371         mutex_unlock(&codec->cache_rw_mutex);
1372         return -ENOSYS;
1373 }
1374 EXPORT_SYMBOL_GPL(snd_soc_cache_write);
1375
1376 /**
1377  * snd_soc_cache_sync: Sync the register cache with the hardware.
1378  *
1379  * @codec: CODEC to configure.
1380  *
1381  * Any registers that should not be synced should be marked as
1382  * volatile.  In general drivers can choose not to use the provided
1383  * syncing functionality if they so require.
1384  */
1385 int snd_soc_cache_sync(struct snd_soc_codec *codec)
1386 {
1387         int ret;
1388         const char *name;
1389
1390         if (!codec->cache_sync) {
1391                 return 0;
1392         }
1393
1394         if (!codec->cache_ops || !codec->cache_ops->sync)
1395                 return -ENOSYS;
1396
1397         if (codec->cache_ops->name)
1398                 name = codec->cache_ops->name;
1399         else
1400                 name = "unknown";
1401
1402         if (codec->cache_ops->name)
1403                 dev_dbg(codec->dev, "Syncing %s cache for %s codec\n",
1404                         codec->cache_ops->name, codec->name);
1405         trace_snd_soc_cache_sync(codec, name, "start");
1406         ret = codec->cache_ops->sync(codec);
1407         if (!ret)
1408                 codec->cache_sync = 0;
1409         trace_snd_soc_cache_sync(codec, name, "end");
1410         return ret;
1411 }
1412 EXPORT_SYMBOL_GPL(snd_soc_cache_sync);
1413
1414 static int snd_soc_get_reg_access_index(struct snd_soc_codec *codec,
1415                                         unsigned int reg)
1416 {
1417         const struct snd_soc_codec_driver *codec_drv;
1418         unsigned int min, max, index;
1419
1420         codec_drv = codec->driver;
1421         min = 0;
1422         max = codec_drv->reg_access_size - 1;
1423         do {
1424                 index = (min + max) / 2;
1425                 if (codec_drv->reg_access_default[index].reg == reg)
1426                         return index;
1427                 if (codec_drv->reg_access_default[index].reg < reg)
1428                         min = index + 1;
1429                 else
1430                         max = index;
1431         } while (min <= max);
1432         return -1;
1433 }
1434
1435 int snd_soc_default_volatile_register(struct snd_soc_codec *codec,
1436                                       unsigned int reg)
1437 {
1438         int index;
1439
1440         if (reg >= codec->driver->reg_cache_size)
1441                 return 1;
1442         index = snd_soc_get_reg_access_index(codec, reg);
1443         if (index < 0)
1444                 return 0;
1445         return codec->driver->reg_access_default[index].vol;
1446 }
1447 EXPORT_SYMBOL_GPL(snd_soc_default_volatile_register);
1448
1449 int snd_soc_default_readable_register(struct snd_soc_codec *codec,
1450                                       unsigned int reg)
1451 {
1452         int index;
1453
1454         if (reg >= codec->driver->reg_cache_size)
1455                 return 1;
1456         index = snd_soc_get_reg_access_index(codec, reg);
1457         if (index < 0)
1458                 return 0;
1459         return codec->driver->reg_access_default[index].read;
1460 }
1461 EXPORT_SYMBOL_GPL(snd_soc_default_readable_register);
1462
1463 int snd_soc_default_writable_register(struct snd_soc_codec *codec,
1464                                       unsigned int reg)
1465 {
1466         int index;
1467
1468         if (reg >= codec->driver->reg_cache_size)
1469                 return 1;
1470         index = snd_soc_get_reg_access_index(codec, reg);
1471         if (index < 0)
1472                 return 0;
1473         return codec->driver->reg_access_default[index].write;
1474 }
1475 EXPORT_SYMBOL_GPL(snd_soc_default_writable_register);