sound/soc/codecs/wm8523.c

   1 /*
   2  * wm8523.c  --  WM8523 ALSA SoC Audio driver
   3  *
   4  * Copyright 2009 Wolfson Microelectronics plc
   5  *
   6  * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
   7  *
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License version 2 as
  11  * published by the Free Software Foundation.
  12  */
  13
  14 #include <linux/module.h>
  15 #include <linux/moduleparam.h>
  16 #include <linux/init.h>
  17 #include <linux/delay.h>
  18 #include <linux/pm.h>
  19 #include <linux/i2c.h>
  20 #include <linux/platform_device.h>
  21 #include <linux/regulator/consumer.h>
  22 #include <linux/slab.h>
  23 #include <sound/core.h>
  24 #include <sound/pcm.h>
  25 #include <sound/pcm_params.h>
  26 #include <sound/soc.h>
  27 #include <sound/soc-dapm.h>
  28 #include <sound/initval.h>
  29 #include <sound/tlv.h>
  30
  31 #include "wm8523.h"
  32
  33 static struct snd_soc_codec *wm8523_codec;
  34 struct snd_soc_codec_device soc_codec_dev_wm8523;
  35
  36 #define WM8523_NUM_SUPPLIES 2
  37 static const char *wm8523_supply_names[WM8523_NUM_SUPPLIES] = {
  38         "AVDD",
  39         "LINEVDD",
  40 };
  41
  42 #define WM8523_NUM_RATES 7
  43
  44 /* codec private data */
  45 struct wm8523_priv {
  46         struct snd_soc_codec codec;
  47         u16 reg_cache[WM8523_REGISTER_COUNT];
  48         struct regulator_bulk_data supplies[WM8523_NUM_SUPPLIES];
  49         unsigned int sysclk;
  50         unsigned int rate_constraint_list[WM8523_NUM_RATES];
  51         struct snd_pcm_hw_constraint_list rate_constraint;
  52 };
  53
  54 static const u16 wm8523_reg[WM8523_REGISTER_COUNT] = {
  55         0x8523,     /* R0 - DEVICE_ID */
  56         0x0001,     /* R1 - REVISION */
  57         0x0000,     /* R2 - PSCTRL1 */
  58         0x1812,     /* R3 - AIF_CTRL1 */
  59         0x0000,     /* R4 - AIF_CTRL2 */
  60         0x0001,     /* R5 - DAC_CTRL3 */
  61         0x0190,     /* R6 - DAC_GAINL */
  62         0x0190,     /* R7 - DAC_GAINR */
  63         0x0000,     /* R8 - ZERO_DETECT */
  64 };
  65
  66 static int wm8523_volatile_register(unsigned int reg)
  67 {
  68         switch (reg) {
  69         case WM8523_DEVICE_ID:
  70         case WM8523_REVISION:
  71                 return 1;
  72         default:
  73                 return 0;
  74         }
  75 }
  76
  77 static int wm8523_reset(struct snd_soc_codec *codec)
  78 {
  79         return snd_soc_write(codec, WM8523_DEVICE_ID, 0);
  80 }
  81
  82 static const DECLARE_TLV_DB_SCALE(dac_tlv, -10000, 25, 0);
  83
  84 static const char *wm8523_zd_count_text[] = {
  85         "1024",
  86         "2048",
  87 };
  88
  89 static const struct soc_enum wm8523_zc_count =
  90         SOC_ENUM_SINGLE(WM8523_ZERO_DETECT, 0, 2, wm8523_zd_count_text);
  91
  92 static const struct snd_kcontrol_new wm8523_snd_controls[] = {
  93 SOC_DOUBLE_R_TLV("Playback Volume", WM8523_DAC_GAINL, WM8523_DAC_GAINR,
  94                  0, 448, 0, dac_tlv),
  95 SOC_SINGLE("ZC Switch", WM8523_DAC_CTRL3, 4, 1, 0),
  96 SOC_SINGLE("Playback Deemphasis Switch", WM8523_AIF_CTRL1, 8, 1, 0),
  97 SOC_DOUBLE("Playback Switch", WM8523_DAC_CTRL3, 2, 3, 1, 1),
  98 SOC_SINGLE("Volume Ramp Up Switch", WM8523_DAC_CTRL3, 1, 1, 0),
  99 SOC_SINGLE("Volume Ramp Down Switch", WM8523_DAC_CTRL3, 0, 1, 0),
 100 SOC_ENUM("Zero Detect Count", wm8523_zc_count),
 101 };
 102
 103 static const struct snd_soc_dapm_widget wm8523_dapm_widgets[] = {
 104 SND_SOC_DAPM_DAC("DAC", "Playback", SND_SOC_NOPM, 0, 0),
 105 SND_SOC_DAPM_OUTPUT("LINEVOUTL"),
 106 SND_SOC_DAPM_OUTPUT("LINEVOUTR"),
 107 };
 108
 109 static const struct snd_soc_dapm_route intercon[] = {
 110         { "LINEVOUTL", NULL, "DAC" },
 111         { "LINEVOUTR", NULL, "DAC" },
 112 };
 113
 114 static int wm8523_add_widgets(struct snd_soc_codec *codec)
 115 {
 116         snd_soc_dapm_new_controls(codec, wm8523_dapm_widgets,
 117                                   ARRAY_SIZE(wm8523_dapm_widgets));
 118
 119         snd_soc_dapm_add_routes(codec, intercon, ARRAY_SIZE(intercon));
 120
 121         return 0;
 122 }
 123
 124 static struct {
 125         int value;
 126         int ratio;
 127 } lrclk_ratios[WM8523_NUM_RATES] = {
 128         { 1, 128 },
 129         { 2, 192 },
 130         { 3, 256 },
 131         { 4, 384 },
 132         { 5, 512 },
 133         { 6, 768 },
 134         { 7, 1152 },
 135 };
 136
 137 static int wm8523_startup(struct snd_pcm_substream *substream,
 138                           struct snd_soc_dai *dai)
 139 {
 140         struct snd_soc_codec *codec = dai->codec;
 141         struct wm8523_priv *wm8523 = snd_soc_codec_get_drvdata(codec);
 142
 143         /* The set of sample rates that can be supported depends on the
 144          * MCLK supplied to the CODEC - enforce this.
 145          */
 146         if (!wm8523->sysclk) {
 147                 dev_err(codec->dev,
 148                         "No MCLK configured, call set_sysclk() on init\n");
 149                 return -EINVAL;
 150         }
 151
 152         return 0;
 153         snd_pcm_hw_constraint_list(substream->runtime, 0,
 154                                    SNDRV_PCM_HW_PARAM_RATE,
 155                                    &wm8523->rate_constraint);
 156
 157         return 0;
 158 }
 159
 160 static int wm8523_hw_params(struct snd_pcm_substream *substream,
 161                             struct snd_pcm_hw_params *params,
 162                             struct snd_soc_dai *dai)
 163 {
 164         struct snd_soc_pcm_runtime *rtd = substream->private_data;
 165         struct snd_soc_device *socdev = rtd->socdev;
 166         struct snd_soc_codec *codec = socdev->card->codec;
 167         struct wm8523_priv *wm8523 = snd_soc_codec_get_drvdata(codec);
 168         int i;
 169         u16 aifctrl1 = snd_soc_read(codec, WM8523_AIF_CTRL1);
 170         u16 aifctrl2 = snd_soc_read(codec, WM8523_AIF_CTRL2);
 171
 172         /* Find a supported LRCLK ratio */
 173         for (i = 0; i < ARRAY_SIZE(lrclk_ratios); i++) {
 174                 if (wm8523->sysclk / params_rate(params) ==
 175                     lrclk_ratios[i].ratio)
 176                         break;
 177         }
 178
 179         /* Should never happen, should be handled by constraints */
 180         if (i == ARRAY_SIZE(lrclk_ratios)) {
 181                 dev_err(codec->dev, "MCLK/fs ratio %d unsupported\n",
 182                         wm8523->sysclk / params_rate(params));
 183                 return -EINVAL;
 184         }
 185
 186         aifctrl2 &= ~WM8523_SR_MASK;
 187         aifctrl2 |= lrclk_ratios[i].value;
 188
 189         aifctrl1 &= ~WM8523_WL_MASK;
 190         switch (params_format(params)) {
 191         case SNDRV_PCM_FORMAT_S16_LE:
 192                 break;
 193         case SNDRV_PCM_FORMAT_S20_3LE:
 194                 aifctrl1 |= 0x8;
 195                 break;
 196         case SNDRV_PCM_FORMAT_S24_LE:
 197                 aifctrl1 |= 0x10;
 198                 break;
 199         case SNDRV_PCM_FORMAT_S32_LE:
 200                 aifctrl1 |= 0x18;
 201                 break;
 202         }
 203
 204         snd_soc_write(codec, WM8523_AIF_CTRL1, aifctrl1);
 205         snd_soc_write(codec, WM8523_AIF_CTRL2, aifctrl2);
 206
 207         return 0;
 208 }
 209
 210 static int wm8523_set_dai_sysclk(struct snd_soc_dai *codec_dai,
 211                 int clk_id, unsigned int freq, int dir)
 212 {
 213         struct snd_soc_codec *codec = codec_dai->codec;
 214         struct wm8523_priv *wm8523 = snd_soc_codec_get_drvdata(codec);
 215         unsigned int val;
 216         int i;
 217
 218         wm8523->sysclk = freq;
 219
 220         wm8523->rate_constraint.count = 0;
 221         for (i = 0; i < ARRAY_SIZE(lrclk_ratios); i++) {
 222                 val = freq / lrclk_ratios[i].ratio;
 223                 /* Check that it's a standard rate since core can't
 224                  * cope with others and having the odd rates confuses
 225                  * constraint matching.
 226                  */
 227                 switch (val) {
 228                 case 8000:
 229                 case 11025:
 230                 case 16000:
 231                 case 22050:
 232                 case 32000:
 233                 case 44100:
 234                 case 48000:
 235                 case 64000:
 236                 case 88200:
 237                 case 96000:
 238                 case 176400:
 239                 case 192000:
 240                         dev_dbg(codec->dev, "Supported sample rate: %dHz\n",
 241                                 val);
 242                         wm8523->rate_constraint_list[i] = val;
 243                         wm8523->rate_constraint.count++;
 244                         break;
 245                 default:
 246                         dev_dbg(codec->dev, "Skipping sample rate: %dHz\n",
 247                                 val);
 248                 }
 249         }
 250
 251         /* Need at least one supported rate... */
 252         if (wm8523->rate_constraint.count == 0)
 253                 return -EINVAL;
 254
 255         return 0;
 256 }
 257
 258
 259 static int wm8523_set_dai_fmt(struct snd_soc_dai *codec_dai,
 260                 unsigned int fmt)
 261 {
 262         struct snd_soc_codec *codec = codec_dai->codec;
 263         u16 aifctrl1 = snd_soc_read(codec, WM8523_AIF_CTRL1);
 264
 265         aifctrl1 &= ~(WM8523_BCLK_INV_MASK | WM8523_LRCLK_INV_MASK |
 266                       WM8523_FMT_MASK | WM8523_AIF_MSTR_MASK);
 267
 268         switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
 269         case SND_SOC_DAIFMT_CBM_CFM:
 270                 aifctrl1 |= WM8523_AIF_MSTR;
 271                 break;
 272         case SND_SOC_DAIFMT_CBS_CFS:
 273                 break;
 274         default:
 275                 return -EINVAL;
 276         }
 277
 278         switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
 279         case SND_SOC_DAIFMT_I2S:
 280                 aifctrl1 |= 0x0002;
 281                 break;
 282         case SND_SOC_DAIFMT_RIGHT_J:
 283                 break;
 284         case SND_SOC_DAIFMT_LEFT_J:
 285                 aifctrl1 |= 0x0001;
 286                 break;
 287         case SND_SOC_DAIFMT_DSP_A:
 288                 aifctrl1 |= 0x0003;
 289                 break;
 290         case SND_SOC_DAIFMT_DSP_B:
 291                 aifctrl1 |= 0x0023;
 292                 break;
 293         default:
 294                 return -EINVAL;
 295         }
 296
 297         switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
 298         case SND_SOC_DAIFMT_NB_NF:
 299                 break;
 300         case SND_SOC_DAIFMT_IB_IF:
 301                 aifctrl1 |= WM8523_BCLK_INV | WM8523_LRCLK_INV;
 302                 break;
 303         case SND_SOC_DAIFMT_IB_NF:
 304                 aifctrl1 |= WM8523_BCLK_INV;
 305                 break;
 306         case SND_SOC_DAIFMT_NB_IF:
 307                 aifctrl1 |= WM8523_LRCLK_INV;
 308                 break;
 309         default:
 310                 return -EINVAL;
 311         }
 312
 313         snd_soc_write(codec, WM8523_AIF_CTRL1, aifctrl1);
 314
 315         return 0;
 316 }
 317
 318 static int wm8523_set_bias_level(struct snd_soc_codec *codec,
 319                                  enum snd_soc_bias_level level)
 320 {
 321         struct wm8523_priv *wm8523 = snd_soc_codec_get_drvdata(codec);
 322         int ret, i;
 323
 324         switch (level) {
 325         case SND_SOC_BIAS_ON:
 326                 break;
 327
 328         case SND_SOC_BIAS_PREPARE:
 329                 /* Full power on */
 330                 snd_soc_update_bits(codec, WM8523_PSCTRL1,
 331                                     WM8523_SYS_ENA_MASK, 3);
 332                 break;
 333
 334         case SND_SOC_BIAS_STANDBY:
 335                 if (codec->bias_level == SND_SOC_BIAS_OFF) {
 336                         ret = regulator_bulk_enable(ARRAY_SIZE(wm8523->supplies),
 337                                                     wm8523->supplies);
 338                         if (ret != 0) {
 339                                 dev_err(codec->dev,
 340                                         "Failed to enable supplies: %d\n",
 341                                         ret);
 342                                 return ret;
 343                         }
 344
 345                         /* Initial power up */
 346                         snd_soc_update_bits(codec, WM8523_PSCTRL1,
 347                                             WM8523_SYS_ENA_MASK, 1);
 348
 349                         /* Sync back default/cached values */
 350                         for (i = WM8523_AIF_CTRL1;
 351                              i < WM8523_MAX_REGISTER; i++)
 352                                 snd_soc_write(codec, i, wm8523->reg_cache[i]);
 353
 354
 355                         msleep(100);
 356                 }
 357
 358                 /* Power up to mute */
 359                 snd_soc_update_bits(codec, WM8523_PSCTRL1,
 360                                     WM8523_SYS_ENA_MASK, 2);
 361
 362                 break;
 363
 364         case SND_SOC_BIAS_OFF:
 365                 /* The chip runs through the power down sequence for us. */
 366                 snd_soc_update_bits(codec, WM8523_PSCTRL1,
 367                                     WM8523_SYS_ENA_MASK, 0);
 368                 msleep(100);
 369
 370                 regulator_bulk_disable(ARRAY_SIZE(wm8523->supplies),
 371                                        wm8523->supplies);
 372                 break;
 373         }
 374         codec->bias_level = level;
 375         return 0;
 376 }
 377
 378 #define WM8523_RATES SNDRV_PCM_RATE_8000_192000
 379
 380 #define WM8523_FORMATS (SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S20_3LE |\
 381                         SNDRV_PCM_FMTBIT_S24_LE | SNDRV_PCM_FMTBIT_S32_LE)
 382
 383 static struct snd_soc_dai_ops wm8523_dai_ops = {
 384         .startup        = wm8523_startup,
 385         .hw_params      = wm8523_hw_params,
 386         .set_sysclk     = wm8523_set_dai_sysclk,
 387         .set_fmt        = wm8523_set_dai_fmt,
 388 };
 389
 390 struct snd_soc_dai wm8523_dai = {
 391         .name = "WM8523",
 392         .playback = {
 393                 .stream_name = "Playback",
 394                 .channels_min = 2,  /* Mono modes not yet supported */
 395                 .channels_max = 2,
 396                 .rates = WM8523_RATES,
 397                 .formats = WM8523_FORMATS,
 398         },
 399         .ops = &wm8523_dai_ops,
 400 };
 401 EXPORT_SYMBOL_GPL(wm8523_dai);
 402
 403 #ifdef CONFIG_PM
 404 static int wm8523_suspend(struct platform_device *pdev, pm_message_t state)
 405 {
 406         struct snd_soc_device *socdev = platform_get_drvdata(pdev);
 407         struct snd_soc_codec *codec = socdev->card->codec;
 408
 409         wm8523_set_bias_level(codec, SND_SOC_BIAS_OFF);
 410         return 0;
 411 }
 412
 413 static int wm8523_resume(struct platform_device *pdev)
 414 {
 415         struct snd_soc_device *socdev = platform_get_drvdata(pdev);
 416         struct snd_soc_codec *codec = socdev->card->codec;
 417
 418         wm8523_set_bias_level(codec, SND_SOC_BIAS_STANDBY);
 419
 420         return 0;
 421 }
 422 #else
 423 #define wm8523_suspend NULL
 424 #define wm8523_resume NULL
 425 #endif
 426
 427 static int wm8523_probe(struct platform_device *pdev)
 428 {
 429         struct snd_soc_device *socdev = platform_get_drvdata(pdev);
 430         struct snd_soc_codec *codec;
 431         int ret = 0;
 432
 433         if (wm8523_codec == NULL) {
 434                 dev_err(&pdev->dev, "Codec device not registered\n");
 435                 return -ENODEV;
 436         }
 437
 438         socdev->card->codec = wm8523_codec;
 439         codec = wm8523_codec;
 440
 441         /* register pcms */
 442         ret = snd_soc_new_pcms(socdev, SNDRV_DEFAULT_IDX1, SNDRV_DEFAULT_STR1);
 443         if (ret < 0) {
 444                 dev_err(codec->dev, "failed to create pcms: %d\n", ret);
 445                 goto pcm_err;
 446         }
 447
 448         snd_soc_add_controls(codec, wm8523_snd_controls,
 449                              ARRAY_SIZE(wm8523_snd_controls));
 450         wm8523_add_widgets(codec);
 451
 452         return ret;
 453
 454 pcm_err:
 455         return ret;
 456 }
 457
 458 static int wm8523_remove(struct platform_device *pdev)
 459 {
 460         struct snd_soc_device *socdev = platform_get_drvdata(pdev);
 461
 462         snd_soc_free_pcms(socdev);
 463         snd_soc_dapm_free(socdev);
 464
 465         return 0;
 466 }
 467
 468 struct snd_soc_codec_device soc_codec_dev_wm8523 = {
 469         .probe =        wm8523_probe,
 470         .remove =       wm8523_remove,
 471         .suspend =      wm8523_suspend,
 472         .resume =       wm8523_resume,
 473 };
 474 EXPORT_SYMBOL_GPL(soc_codec_dev_wm8523);
 475
 476 static int wm8523_register(struct wm8523_priv *wm8523,
 477                            enum snd_soc_control_type control)
 478 {
 479         int ret;
 480         struct snd_soc_codec *codec = &wm8523->codec;
 481         int i;
 482
 483         if (wm8523_codec) {
 484                 dev_err(codec->dev, "Another WM8523 is registered\n");
 485                 return -EINVAL;
 486         }
 487
 488         mutex_init(&codec->mutex);
 489         INIT_LIST_HEAD(&codec->dapm_widgets);
 490         INIT_LIST_HEAD(&codec->dapm_paths);
 491
 492         snd_soc_codec_set_drvdata(codec, wm8523);
 493         codec->name = "WM8523";
 494         codec->owner = THIS_MODULE;
 495         codec->bias_level = SND_SOC_BIAS_OFF;
 496         codec->set_bias_level = wm8523_set_bias_level;
 497         codec->dai = &wm8523_dai;
 498         codec->num_dai = 1;
 499         codec->reg_cache_size = WM8523_REGISTER_COUNT;
 500         codec->reg_cache = &wm8523->reg_cache;
 501         codec->volatile_register = wm8523_volatile_register;
 502
 503         wm8523->rate_constraint.list = &wm8523->rate_constraint_list[0];
 504         wm8523->rate_constraint.count =
 505                 ARRAY_SIZE(wm8523->rate_constraint_list);
 506
 507         memcpy(codec->reg_cache, wm8523_reg, sizeof(wm8523_reg));
 508
 509         ret = snd_soc_codec_set_cache_io(codec, 8, 16, control);
 510         if (ret != 0) {
 511                 dev_err(codec->dev, "Failed to set cache I/O: %d\n", ret);
 512                 goto err;
 513         }
 514
 515         for (i = 0; i < ARRAY_SIZE(wm8523->supplies); i++)
 516                 wm8523->supplies[i].supply = wm8523_supply_names[i];
 517
 518         ret = regulator_bulk_get(codec->dev, ARRAY_SIZE(wm8523->supplies),
 519                                  wm8523->supplies);
 520         if (ret != 0) {
 521                 dev_err(codec->dev, "Failed to request supplies: %d\n", ret);
 522                 goto err;
 523         }
 524
 525         ret = regulator_bulk_enable(ARRAY_SIZE(wm8523->supplies),
 526                                     wm8523->supplies);
 527         if (ret != 0) {
 528                 dev_err(codec->dev, "Failed to enable supplies: %d\n", ret);
 529                 goto err_get;
 530         }
 531
 532         ret = snd_soc_read(codec, WM8523_DEVICE_ID);
 533         if (ret < 0) {
 534                 dev_err(codec->dev, "Failed to read ID register\n");
 535                 goto err_enable;
 536         }
 537         if (ret != wm8523_reg[WM8523_DEVICE_ID]) {
 538                 dev_err(codec->dev, "Device is not a WM8523, ID is %x\n", ret);
 539                 ret = -EINVAL;
 540                 goto err_enable;
 541         }
 542
 543         ret = snd_soc_read(codec, WM8523_REVISION);
 544         if (ret < 0) {
 545                 dev_err(codec->dev, "Failed to read revision register\n");
 546                 goto err_enable;
 547         }
 548         dev_info(codec->dev, "revision %c\n",
 549                  (ret & WM8523_CHIP_REV_MASK) + 'A');
 550
 551         ret = wm8523_reset(codec);
 552         if (ret < 0) {
 553                 dev_err(codec->dev, "Failed to issue reset\n");
 554                 goto err_enable;
 555         }
 556
 557         wm8523_dai.dev = codec->dev;
 558
 559         /* Change some default settings - latch VU and enable ZC */
 560         wm8523->reg_cache[WM8523_DAC_GAINR] |= WM8523_DACR_VU;
 561         wm8523->reg_cache[WM8523_DAC_CTRL3] |= WM8523_ZC;
 562
 563         wm8523_set_bias_level(codec, SND_SOC_BIAS_STANDBY);
 564
 565         /* Bias level configuration will have done an extra enable */
 566         regulator_bulk_disable(ARRAY_SIZE(wm8523->supplies), wm8523->supplies);
 567
 568         wm8523_codec = codec;
 569
 570         ret = snd_soc_register_codec(codec);
 571         if (ret != 0) {
 572                 dev_err(codec->dev, "Failed to register codec: %d\n", ret);
 573                 return ret;
 574         }
 575
 576         ret = snd_soc_register_dai(&wm8523_dai);
 577         if (ret != 0) {
 578                 dev_err(codec->dev, "Failed to register DAI: %d\n", ret);
 579                 snd_soc_unregister_codec(codec);
 580                 return ret;
 581         }
 582
 583         return 0;
 584
 585 err_enable:
 586         regulator_bulk_disable(ARRAY_SIZE(wm8523->supplies), wm8523->supplies);
 587 err_get:
 588         regulator_bulk_free(ARRAY_SIZE(wm8523->supplies), wm8523->supplies);
 589 err:
 590         kfree(wm8523);
 591         return ret;
 592 }
 593
 594 static void wm8523_unregister(struct wm8523_priv *wm8523)
 595 {
 596         wm8523_set_bias_level(&wm8523->codec, SND_SOC_BIAS_OFF);
 597         regulator_bulk_free(ARRAY_SIZE(wm8523->supplies), wm8523->supplies);
 598         snd_soc_unregister_dai(&wm8523_dai);
 599         snd_soc_unregister_codec(&wm8523->codec);
 600         kfree(wm8523);
 601         wm8523_codec = NULL;
 602 }
 603
 604 #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
 605 static __devinit int wm8523_i2c_probe(struct i2c_client *i2c,
 606                                       const struct i2c_device_id *id)
 607 {
 608         struct wm8523_priv *wm8523;
 609         struct snd_soc_codec *codec;
 610
 611         wm8523 = kzalloc(sizeof(struct wm8523_priv), GFP_KERNEL);
 612         if (wm8523 == NULL)
 613                 return -ENOMEM;
 614
 615         codec = &wm8523->codec;
 616         codec->hw_write = (hw_write_t)i2c_master_send;
 617
 618         i2c_set_clientdata(i2c, wm8523);
 619         codec->control_data = i2c;
 620
 621         codec->dev = &i2c->dev;
 622
 623         return wm8523_register(wm8523, SND_SOC_I2C);
 624 }
 625
 626 static __devexit int wm8523_i2c_remove(struct i2c_client *client)
 627 {
 628         struct wm8523_priv *wm8523 = i2c_get_clientdata(client);
 629         wm8523_unregister(wm8523);
 630         return 0;
 631 }
 632
 633 static const struct i2c_device_id wm8523_i2c_id[] = {
 634         { "wm8523", 0 },
 635         { }
 636 };
 637 MODULE_DEVICE_TABLE(i2c, wm8523_i2c_id);
 638
 639 static struct i2c_driver wm8523_i2c_driver = {
 640         .driver = {
 641                 .name = "WM8523",
 642                 .owner = THIS_MODULE,
 643         },
 644         .probe =    wm8523_i2c_probe,
 645         .remove =   __devexit_p(wm8523_i2c_remove),
 646         .id_table = wm8523_i2c_id,
 647 };
 648 #endif
 649
 650 static int __init wm8523_modinit(void)
 651 {
 652         int ret;
 653 #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
 654         ret = i2c_add_driver(&wm8523_i2c_driver);
 655         if (ret != 0) {
 656                 printk(KERN_ERR "Failed to register WM8523 I2C driver: %d\n",
 657                        ret);
 658         }
 659 #endif
 660         return 0;
 661 }
 662 module_init(wm8523_modinit);
 663
 664 static void __exit wm8523_exit(void)
 665 {
 666 #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
 667         i2c_del_driver(&wm8523_i2c_driver);
 668 #endif
 669 }
 670 module_exit(wm8523_exit);
 671
 672 MODULE_DESCRIPTION("ASoC WM8523 driver");
 673 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
 674 MODULE_LICENSE("GPL");