sound/soc/codecs/wm8741.c

   1 /*
   2  * wm8741.c  --  WM8741 ALSA SoC Audio driver
   3  *
   4  * Copyright 2010 Wolfson Microelectronics plc
   5  *
   6  * Author: Ian Lartey <ian@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/spi/spi.h>
  21 #include <linux/platform_device.h>
  22 #include <linux/regulator/consumer.h>
  23 #include <linux/slab.h>
  24 #include <linux/of_device.h>
  25 #include <sound/core.h>
  26 #include <sound/pcm.h>
  27 #include <sound/pcm_params.h>
  28 #include <sound/soc.h>
  29 #include <sound/initval.h>
  30 #include <sound/tlv.h>
  31
  32 #include "wm8741.h"
  33
  34 #define WM8741_NUM_SUPPLIES 2
  35 static const char *wm8741_supply_names[WM8741_NUM_SUPPLIES] = {
  36         "AVDD",
  37         "DVDD",
  38 };
  39
  40 #define WM8741_NUM_RATES 6
  41
  42 /* codec private data */
  43 struct wm8741_priv {
  44         enum snd_soc_control_type control_type;
  45         struct regulator_bulk_data supplies[WM8741_NUM_SUPPLIES];
  46         unsigned int sysclk;
  47         struct snd_pcm_hw_constraint_list *sysclk_constraints;
  48 };
  49
  50 static const u16 wm8741_reg_defaults[WM8741_REGISTER_COUNT] = {
  51         0x0000,     /* R0  - DACLLSB Attenuation */
  52         0x0000,     /* R1  - DACLMSB Attenuation */
  53         0x0000,     /* R2  - DACRLSB Attenuation */
  54         0x0000,     /* R3  - DACRMSB Attenuation */
  55         0x0000,     /* R4  - Volume Control */
  56         0x000A,     /* R5  - Format Control */
  57         0x0000,     /* R6  - Filter Control */
  58         0x0000,     /* R7  - Mode Control 1 */
  59         0x0002,     /* R8  - Mode Control 2 */
  60         0x0000,     /* R9  - Reset */
  61         0x0002,     /* R32 - ADDITONAL_CONTROL_1 */
  62 };
  63
  64
  65 static int wm8741_reset(struct snd_soc_codec *codec)
  66 {
  67         return snd_soc_write(codec, WM8741_RESET, 0);
  68 }
  69
  70 static const DECLARE_TLV_DB_SCALE(dac_tlv_fine, -12700, 13, 0);
  71 static const DECLARE_TLV_DB_SCALE(dac_tlv, -12700, 400, 0);
  72
  73 static const struct snd_kcontrol_new wm8741_snd_controls[] = {
  74 SOC_DOUBLE_R_TLV("Fine Playback Volume", WM8741_DACLLSB_ATTENUATION,
  75                  WM8741_DACRLSB_ATTENUATION, 1, 255, 1, dac_tlv_fine),
  76 SOC_DOUBLE_R_TLV("Playback Volume", WM8741_DACLMSB_ATTENUATION,
  77                  WM8741_DACRMSB_ATTENUATION, 0, 511, 1, dac_tlv),
  78 };
  79
  80 static const struct snd_soc_dapm_widget wm8741_dapm_widgets[] = {
  81 SND_SOC_DAPM_DAC("DACL", "Playback", SND_SOC_NOPM, 0, 0),
  82 SND_SOC_DAPM_DAC("DACR", "Playback", SND_SOC_NOPM, 0, 0),
  83 SND_SOC_DAPM_OUTPUT("VOUTLP"),
  84 SND_SOC_DAPM_OUTPUT("VOUTLN"),
  85 SND_SOC_DAPM_OUTPUT("VOUTRP"),
  86 SND_SOC_DAPM_OUTPUT("VOUTRN"),
  87 };
  88
  89 static const struct snd_soc_dapm_route intercon[] = {
  90         { "VOUTLP", NULL, "DACL" },
  91         { "VOUTLN", NULL, "DACL" },
  92         { "VOUTRP", NULL, "DACR" },
  93         { "VOUTRN", NULL, "DACR" },
  94 };
  95
  96 static int wm8741_add_widgets(struct snd_soc_codec *codec)
  97 {
  98         struct snd_soc_dapm_context *dapm = &codec->dapm;
  99
 100         snd_soc_dapm_new_controls(dapm, wm8741_dapm_widgets,
 101                                   ARRAY_SIZE(wm8741_dapm_widgets));
 102         snd_soc_dapm_add_routes(dapm, intercon, ARRAY_SIZE(intercon));
 103
 104         return 0;
 105 }
 106
 107 static struct {
 108         int value;
 109         int ratio;
 110 } lrclk_ratios[WM8741_NUM_RATES] = {
 111         { 1, 128 },
 112         { 2, 192 },
 113         { 3, 256 },
 114         { 4, 384 },
 115         { 5, 512 },
 116         { 6, 768 },
 117 };
 118
 119 static unsigned int rates_11289[] = {
 120         44100, 88235,
 121 };
 122
 123 static struct snd_pcm_hw_constraint_list constraints_11289 = {
 124         .count  = ARRAY_SIZE(rates_11289),
 125         .list   = rates_11289,
 126 };
 127
 128 static unsigned int rates_12288[] = {
 129         32000, 48000, 96000,
 130 };
 131
 132 static struct snd_pcm_hw_constraint_list constraints_12288 = {
 133         .count  = ARRAY_SIZE(rates_12288),
 134         .list   = rates_12288,
 135 };
 136
 137 static unsigned int rates_16384[] = {
 138         32000,
 139 };
 140
 141 static struct snd_pcm_hw_constraint_list constraints_16384 = {
 142         .count  = ARRAY_SIZE(rates_16384),
 143         .list   = rates_16384,
 144 };
 145
 146 static unsigned int rates_16934[] = {
 147         44100, 88235,
 148 };
 149
 150 static struct snd_pcm_hw_constraint_list constraints_16934 = {
 151         .count  = ARRAY_SIZE(rates_16934),
 152         .list   = rates_16934,
 153 };
 154
 155 static unsigned int rates_18432[] = {
 156         48000, 96000,
 157 };
 158
 159 static struct snd_pcm_hw_constraint_list constraints_18432 = {
 160         .count  = ARRAY_SIZE(rates_18432),
 161         .list   = rates_18432,
 162 };
 163
 164 static unsigned int rates_22579[] = {
 165         44100, 88235, 1764000
 166 };
 167
 168 static struct snd_pcm_hw_constraint_list constraints_22579 = {
 169         .count  = ARRAY_SIZE(rates_22579),
 170         .list   = rates_22579,
 171 };
 172
 173 static unsigned int rates_24576[] = {
 174         32000, 48000, 96000, 192000
 175 };
 176
 177 static struct snd_pcm_hw_constraint_list constraints_24576 = {
 178         .count  = ARRAY_SIZE(rates_24576),
 179         .list   = rates_24576,
 180 };
 181
 182 static unsigned int rates_36864[] = {
 183         48000, 96000, 19200
 184 };
 185
 186 static struct snd_pcm_hw_constraint_list constraints_36864 = {
 187         .count  = ARRAY_SIZE(rates_36864),
 188         .list   = rates_36864,
 189 };
 190
 191
 192 static int wm8741_startup(struct snd_pcm_substream *substream,
 193                           struct snd_soc_dai *dai)
 194 {
 195         struct snd_soc_codec *codec = dai->codec;
 196         struct wm8741_priv *wm8741 = snd_soc_codec_get_drvdata(codec);
 197
 198         /* The set of sample rates that can be supported depends on the
 199          * MCLK supplied to the CODEC - enforce this.
 200          */
 201         if (!wm8741->sysclk) {
 202                 dev_err(codec->dev,
 203                         "No MCLK configured, call set_sysclk() on init\n");
 204                 return -EINVAL;
 205         }
 206
 207         snd_pcm_hw_constraint_list(substream->runtime, 0,
 208                                    SNDRV_PCM_HW_PARAM_RATE,
 209                                    wm8741->sysclk_constraints);
 210
 211         return 0;
 212 }
 213
 214 static int wm8741_hw_params(struct snd_pcm_substream *substream,
 215                             struct snd_pcm_hw_params *params,
 216                             struct snd_soc_dai *dai)
 217 {
 218         struct snd_soc_pcm_runtime *rtd = substream->private_data;
 219         struct snd_soc_codec *codec = rtd->codec;
 220         struct wm8741_priv *wm8741 = snd_soc_codec_get_drvdata(codec);
 221         u16 iface = snd_soc_read(codec, WM8741_FORMAT_CONTROL) & 0x1FC;
 222         int i;
 223
 224         /* Find a supported LRCLK ratio */
 225         for (i = 0; i < ARRAY_SIZE(lrclk_ratios); i++) {
 226                 if (wm8741->sysclk / params_rate(params) ==
 227                     lrclk_ratios[i].ratio)
 228                         break;
 229         }
 230
 231         /* Should never happen, should be handled by constraints */
 232         if (i == ARRAY_SIZE(lrclk_ratios)) {
 233                 dev_err(codec->dev, "MCLK/fs ratio %d unsupported\n",
 234                         wm8741->sysclk / params_rate(params));
 235                 return -EINVAL;
 236         }
 237
 238         /* bit size */
 239         switch (params_format(params)) {
 240         case SNDRV_PCM_FORMAT_S16_LE:
 241                 break;
 242         case SNDRV_PCM_FORMAT_S20_3LE:
 243                 iface |= 0x0001;
 244                 break;
 245         case SNDRV_PCM_FORMAT_S24_LE:
 246                 iface |= 0x0002;
 247                 break;
 248         case SNDRV_PCM_FORMAT_S32_LE:
 249                 iface |= 0x0003;
 250                 break;
 251         default:
 252                 dev_dbg(codec->dev, "wm8741_hw_params:    Unsupported bit size param = %d",
 253                         params_format(params));
 254                 return -EINVAL;
 255         }
 256
 257         dev_dbg(codec->dev, "wm8741_hw_params:    bit size param = %d",
 258                 params_format(params));
 259
 260         snd_soc_write(codec, WM8741_FORMAT_CONTROL, iface);
 261         return 0;
 262 }
 263
 264 static int wm8741_set_dai_sysclk(struct snd_soc_dai *codec_dai,
 265                 int clk_id, unsigned int freq, int dir)
 266 {
 267         struct snd_soc_codec *codec = codec_dai->codec;
 268         struct wm8741_priv *wm8741 = snd_soc_codec_get_drvdata(codec);
 269
 270         dev_dbg(codec->dev, "wm8741_set_dai_sysclk info: freq=%dHz\n", freq);
 271
 272         switch (freq) {
 273         case 11289600:
 274                 wm8741->sysclk_constraints = &constraints_11289;
 275                 wm8741->sysclk = freq;
 276                 return 0;
 277
 278         case 12288000:
 279                 wm8741->sysclk_constraints = &constraints_12288;
 280                 wm8741->sysclk = freq;
 281                 return 0;
 282
 283         case 16384000:
 284                 wm8741->sysclk_constraints = &constraints_16384;
 285                 wm8741->sysclk = freq;
 286                 return 0;
 287
 288         case 16934400:
 289                 wm8741->sysclk_constraints = &constraints_16934;
 290                 wm8741->sysclk = freq;
 291                 return 0;
 292
 293         case 18432000:
 294                 wm8741->sysclk_constraints = &constraints_18432;
 295                 wm8741->sysclk = freq;
 296                 return 0;
 297
 298         case 22579200:
 299         case 33868800:
 300                 wm8741->sysclk_constraints = &constraints_22579;
 301                 wm8741->sysclk = freq;
 302                 return 0;
 303
 304         case 24576000:
 305                 wm8741->sysclk_constraints = &constraints_24576;
 306                 wm8741->sysclk = freq;
 307                 return 0;
 308
 309         case 36864000:
 310                 wm8741->sysclk_constraints = &constraints_36864;
 311                 wm8741->sysclk = freq;
 312                 return 0;
 313         }
 314         return -EINVAL;
 315 }
 316
 317 static int wm8741_set_dai_fmt(struct snd_soc_dai *codec_dai,
 318                 unsigned int fmt)
 319 {
 320         struct snd_soc_codec *codec = codec_dai->codec;
 321         u16 iface = snd_soc_read(codec, WM8741_FORMAT_CONTROL) & 0x1C3;
 322
 323         /* check master/slave audio interface */
 324         switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
 325         case SND_SOC_DAIFMT_CBS_CFS:
 326                 break;
 327         default:
 328                 return -EINVAL;
 329         }
 330
 331         /* interface format */
 332         switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
 333         case SND_SOC_DAIFMT_I2S:
 334                 iface |= 0x0008;
 335                 break;
 336         case SND_SOC_DAIFMT_RIGHT_J:
 337                 break;
 338         case SND_SOC_DAIFMT_LEFT_J:
 339                 iface |= 0x0004;
 340                 break;
 341         case SND_SOC_DAIFMT_DSP_A:
 342                 iface |= 0x000C;
 343                 break;
 344         case SND_SOC_DAIFMT_DSP_B:
 345                 iface |= 0x001C;
 346                 break;
 347         default:
 348                 return -EINVAL;
 349         }
 350
 351         /* clock inversion */
 352         switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
 353         case SND_SOC_DAIFMT_NB_NF:
 354                 break;
 355         case SND_SOC_DAIFMT_IB_IF:
 356                 iface |= 0x0010;
 357                 break;
 358         case SND_SOC_DAIFMT_IB_NF:
 359                 iface |= 0x0020;
 360                 break;
 361         case SND_SOC_DAIFMT_NB_IF:
 362                 iface |= 0x0030;
 363                 break;
 364         default:
 365                 return -EINVAL;
 366         }
 367
 368
 369         dev_dbg(codec->dev, "wm8741_set_dai_fmt:    Format=%x, Clock Inv=%x\n",
 370                                 fmt & SND_SOC_DAIFMT_FORMAT_MASK,
 371                                 ((fmt & SND_SOC_DAIFMT_INV_MASK)));
 372
 373         snd_soc_write(codec, WM8741_FORMAT_CONTROL, iface);
 374         return 0;
 375 }
 376
 377 #define WM8741_RATES (SNDRV_PCM_RATE_32000 | SNDRV_PCM_RATE_44100 | \
 378                         SNDRV_PCM_RATE_48000 | SNDRV_PCM_RATE_88200 | \
 379                         SNDRV_PCM_RATE_96000 | SNDRV_PCM_RATE_176400 | \
 380                         SNDRV_PCM_RATE_192000)
 381
 382 #define WM8741_FORMATS (SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S20_3LE |\
 383                         SNDRV_PCM_FMTBIT_S24_LE | SNDRV_PCM_FMTBIT_S32_LE)
 384
 385 static struct snd_soc_dai_ops wm8741_dai_ops = {
 386         .startup        = wm8741_startup,
 387         .hw_params      = wm8741_hw_params,
 388         .set_sysclk     = wm8741_set_dai_sysclk,
 389         .set_fmt        = wm8741_set_dai_fmt,
 390 };
 391
 392 static struct snd_soc_dai_driver wm8741_dai = {
 393         .name = "wm8741",
 394         .playback = {
 395                 .stream_name = "Playback",
 396                 .channels_min = 2,  /* Mono modes not yet supported */
 397                 .channels_max = 2,
 398                 .rates = WM8741_RATES,
 399                 .formats = WM8741_FORMATS,
 400         },
 401         .ops = &wm8741_dai_ops,
 402 };
 403
 404 #ifdef CONFIG_PM
 405 static int wm8741_resume(struct snd_soc_codec *codec)
 406 {
 407         u16 *cache = codec->reg_cache;
 408         int i;
 409
 410         /* RESTORE REG Cache */
 411         for (i = 0; i < WM8741_REGISTER_COUNT; i++) {
 412                 if (cache[i] == wm8741_reg_defaults[i] || WM8741_RESET == i)
 413                         continue;
 414                 snd_soc_write(codec, i, cache[i]);
 415         }
 416         return 0;
 417 }
 418 #else
 419 #define wm8741_suspend NULL
 420 #define wm8741_resume NULL
 421 #endif
 422
 423 static int wm8741_probe(struct snd_soc_codec *codec)
 424 {
 425         struct wm8741_priv *wm8741 = snd_soc_codec_get_drvdata(codec);
 426         int ret = 0;
 427         int i;
 428
 429         for (i = 0; i < ARRAY_SIZE(wm8741->supplies); i++)
 430                 wm8741->supplies[i].supply = wm8741_supply_names[i];
 431
 432         ret = regulator_bulk_get(codec->dev, ARRAY_SIZE(wm8741->supplies),
 433                                  wm8741->supplies);
 434         if (ret != 0) {
 435                 dev_err(codec->dev, "Failed to request supplies: %d\n", ret);
 436                 goto err;
 437         }
 438
 439         ret = regulator_bulk_enable(ARRAY_SIZE(wm8741->supplies),
 440                                     wm8741->supplies);
 441         if (ret != 0) {
 442                 dev_err(codec->dev, "Failed to enable supplies: %d\n", ret);
 443                 goto err_get;
 444         }
 445
 446         ret = snd_soc_codec_set_cache_io(codec, 7, 9, wm8741->control_type);
 447         if (ret != 0) {
 448                 dev_err(codec->dev, "Failed to set cache I/O: %d\n", ret);
 449                 goto err_enable;
 450         }
 451
 452         ret = wm8741_reset(codec);
 453         if (ret < 0) {
 454                 dev_err(codec->dev, "Failed to issue reset\n");
 455                 goto err_enable;
 456         }
 457
 458         /* Change some default settings - latch VU */
 459         snd_soc_update_bits(codec, WM8741_DACLLSB_ATTENUATION,
 460                             WM8741_UPDATELL, WM8741_UPDATELL);
 461         snd_soc_update_bits(codec, WM8741_DACLMSB_ATTENUATION,
 462                             WM8741_UPDATELM, WM8741_UPDATELM);
 463         snd_soc_update_bits(codec, WM8741_DACRLSB_ATTENUATION,
 464                             WM8741_UPDATERL, WM8741_UPDATERL);
 465         snd_soc_update_bits(codec, WM8741_DACRMSB_ATTENUATION,
 466                             WM8741_UPDATERM, WM8741_UPDATERM);
 467
 468         snd_soc_add_controls(codec, wm8741_snd_controls,
 469                              ARRAY_SIZE(wm8741_snd_controls));
 470         wm8741_add_widgets(codec);
 471
 472         dev_dbg(codec->dev, "Successful registration\n");
 473         return ret;
 474
 475 err_enable:
 476         regulator_bulk_disable(ARRAY_SIZE(wm8741->supplies), wm8741->supplies);
 477 err_get:
 478         regulator_bulk_free(ARRAY_SIZE(wm8741->supplies), wm8741->supplies);
 479 err:
 480         return ret;
 481 }
 482
 483 static int wm8741_remove(struct snd_soc_codec *codec)
 484 {
 485         struct wm8741_priv *wm8741 = snd_soc_codec_get_drvdata(codec);
 486
 487         regulator_bulk_disable(ARRAY_SIZE(wm8741->supplies), wm8741->supplies);
 488         regulator_bulk_free(ARRAY_SIZE(wm8741->supplies), wm8741->supplies);
 489
 490         return 0;
 491 }
 492
 493 static struct snd_soc_codec_driver soc_codec_dev_wm8741 = {
 494         .probe =        wm8741_probe,
 495         .remove =       wm8741_remove,
 496         .resume =       wm8741_resume,
 497         .reg_cache_size = ARRAY_SIZE(wm8741_reg_defaults),
 498         .reg_word_size = sizeof(u16),
 499         .reg_cache_default = wm8741_reg_defaults,
 500 };
 501
 502 static const struct of_device_id wm8741_of_match[] = {
 503         { .compatible = "wlf,wm8741", },
 504         { }
 505 };
 506 MODULE_DEVICE_TABLE(of, wm8741_of_match);
 507
 508 #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
 509 static int wm8741_i2c_probe(struct i2c_client *i2c,
 510                             const struct i2c_device_id *id)
 511 {
 512         struct wm8741_priv *wm8741;
 513         int ret;
 514
 515         wm8741 = kzalloc(sizeof(struct wm8741_priv), GFP_KERNEL);
 516         if (wm8741 == NULL)
 517                 return -ENOMEM;
 518
 519         i2c_set_clientdata(i2c, wm8741);
 520         wm8741->control_type = SND_SOC_I2C;
 521
 522         ret = snd_soc_register_codec(&i2c->dev,
 523                                      &soc_codec_dev_wm8741, &wm8741_dai, 1);
 524         if (ret != 0)
 525                 goto err;
 526
 527         return ret;
 528
 529 err:
 530         kfree(wm8741);
 531         return ret;
 532 }
 533
 534 static int wm8741_i2c_remove(struct i2c_client *client)
 535 {
 536         snd_soc_unregister_codec(&client->dev);
 537         kfree(i2c_get_clientdata(client));
 538         return 0;
 539 }
 540
 541 static const struct i2c_device_id wm8741_i2c_id[] = {
 542         { "wm8741", 0 },
 543         { }
 544 };
 545 MODULE_DEVICE_TABLE(i2c, wm8741_i2c_id);
 546
 547 static struct i2c_driver wm8741_i2c_driver = {
 548         .driver = {
 549                 .name = "wm8741",
 550                 .owner = THIS_MODULE,
 551                 .of_match_table = wm8741_of_match,
 552         },
 553         .probe =    wm8741_i2c_probe,
 554         .remove =   wm8741_i2c_remove,
 555         .id_table = wm8741_i2c_id,
 556 };
 557 #endif
 558
 559 #if defined(CONFIG_SPI_MASTER)
 560 static int __devinit wm8741_spi_probe(struct spi_device *spi)
 561 {
 562         struct wm8741_priv *wm8741;
 563         int ret;
 564
 565         wm8741 = kzalloc(sizeof(struct wm8741_priv), GFP_KERNEL);
 566         if (wm8741 == NULL)
 567                 return -ENOMEM;
 568
 569         wm8741->control_type = SND_SOC_SPI;
 570         spi_set_drvdata(spi, wm8741);
 571
 572         ret = snd_soc_register_codec(&spi->dev,
 573                         &soc_codec_dev_wm8741, &wm8741_dai, 1);
 574         if (ret < 0)
 575                 kfree(wm8741);
 576         return ret;
 577 }
 578
 579 static int __devexit wm8741_spi_remove(struct spi_device *spi)
 580 {
 581         snd_soc_unregister_codec(&spi->dev);
 582         kfree(spi_get_drvdata(spi));
 583         return 0;
 584 }
 585
 586 static struct spi_driver wm8741_spi_driver = {
 587         .driver = {
 588                 .name   = "wm8741",
 589                 .owner  = THIS_MODULE,
 590                 .of_match_table = wm8741_of_match,
 591         },
 592         .probe          = wm8741_spi_probe,
 593         .remove         = __devexit_p(wm8741_spi_remove),
 594 };
 595 #endif /* CONFIG_SPI_MASTER */
 596
 597 static int __init wm8741_modinit(void)
 598 {
 599         int ret = 0;
 600
 601 #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
 602         ret = i2c_add_driver(&wm8741_i2c_driver);
 603         if (ret != 0)
 604                 pr_err("Failed to register WM8741 I2C driver: %d\n", ret);
 605 #endif
 606 #if defined(CONFIG_SPI_MASTER)
 607         ret = spi_register_driver(&wm8741_spi_driver);
 608         if (ret != 0) {
 609                 printk(KERN_ERR "Failed to register wm8741 SPI driver: %d\n",
 610                        ret);
 611         }
 612 #endif
 613
 614         return ret;
 615 }
 616 module_init(wm8741_modinit);
 617
 618 static void __exit wm8741_exit(void)
 619 {
 620 #if defined(CONFIG_SPI_MASTER)
 621         spi_unregister_driver(&wm8741_spi_driver);
 622 #endif
 623 #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
 624         i2c_del_driver(&wm8741_i2c_driver);
 625 #endif
 626 }
 627 module_exit(wm8741_exit);
 628
 629 MODULE_DESCRIPTION("ASoC WM8741 driver");
 630 MODULE_AUTHOR("Ian Lartey <ian@opensource.wolfsonmicro.com>");
 631 MODULE_LICENSE("GPL");