Pileus Git - ~andy/linux/blob - drivers/mfd/wm8994-core.c

   1 /*
   2  * wm8994-core.c  --  Device access for Wolfson WM8994
   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
  15 #include <linux/kernel.h>
  16 #include <linux/module.h>
  17 #include <linux/slab.h>
  18 #include <linux/i2c.h>
  19 #include <linux/err.h>
  20 #include <linux/delay.h>
  21 #include <linux/mfd/core.h>
  22 #include <linux/pm_runtime.h>
  23 #include <linux/regmap.h>
  24 #include <linux/regulator/consumer.h>
  25 #include <linux/regulator/machine.h>
  26
  27 #include <linux/mfd/wm8994/core.h>
  28 #include <linux/mfd/wm8994/pdata.h>
  29 #include <linux/mfd/wm8994/registers.h>
  30
  31 #include "wm8994.h"
  32
  33 /**
  34  * wm8994_reg_read: Read a single WM8994 register.
  35  *
  36  * @wm8994: Device to read from.
  37  * @reg: Register to read.
  38  */
  39 int wm8994_reg_read(struct wm8994 *wm8994, unsigned short reg)
  40 {
  41         unsigned int val;
  42         int ret;
  43
  44         ret = regmap_read(wm8994->regmap, reg, &val);
  45
  46         if (ret < 0)
  47                 return ret;
  48         else
  49                 return val;
  50 }
  51 EXPORT_SYMBOL_GPL(wm8994_reg_read);
  52
  53 /**
  54  * wm8994_bulk_read: Read multiple WM8994 registers
  55  *
  56  * @wm8994: Device to read from
  57  * @reg: First register
  58  * @count: Number of registers
  59  * @buf: Buffer to fill.  The data will be returned big endian.
  60  */
  61 int wm8994_bulk_read(struct wm8994 *wm8994, unsigned short reg,
  62                      int count, u16 *buf)
  63 {
  64         return regmap_bulk_read(wm8994->regmap, reg, buf, count);
  65 }
  66
  67 /**
  68  * wm8994_reg_write: Write a single WM8994 register.
  69  *
  70  * @wm8994: Device to write to.
  71  * @reg: Register to write to.
  72  * @val: Value to write.
  73  */
  74 int wm8994_reg_write(struct wm8994 *wm8994, unsigned short reg,
  75                      unsigned short val)
  76 {
  77         return regmap_write(wm8994->regmap, reg, val);
  78 }
  79 EXPORT_SYMBOL_GPL(wm8994_reg_write);
  80
  81 /**
  82  * wm8994_bulk_write: Write multiple WM8994 registers
  83  *
  84  * @wm8994: Device to write to
  85  * @reg: First register
  86  * @count: Number of registers
  87  * @buf: Buffer to write from.  Data must be big-endian formatted.
  88  */
  89 int wm8994_bulk_write(struct wm8994 *wm8994, unsigned short reg,
  90                       int count, const u16 *buf)
  91 {
  92         return regmap_raw_write(wm8994->regmap, reg, buf, count * sizeof(u16));
  93 }
  94 EXPORT_SYMBOL_GPL(wm8994_bulk_write);
  95
  96 /**
  97  * wm8994_set_bits: Set the value of a bitfield in a WM8994 register
  98  *
  99  * @wm8994: Device to write to.
 100  * @reg: Register to write to.
 101  * @mask: Mask of bits to set.
 102  * @val: Value to set (unshifted)
 103  */
 104 int wm8994_set_bits(struct wm8994 *wm8994, unsigned short reg,
 105                     unsigned short mask, unsigned short val)
 106 {
 107         return regmap_update_bits(wm8994->regmap, reg, mask, val);
 108 }
 109 EXPORT_SYMBOL_GPL(wm8994_set_bits);
 110
 111 static struct mfd_cell wm8994_regulator_devs[] = {
 112         {
 113                 .name = "wm8994-ldo",
 114                 .id = 1,
 115                 .pm_runtime_no_callbacks = true,
 116         },
 117         {
 118                 .name = "wm8994-ldo",
 119                 .id = 2,
 120                 .pm_runtime_no_callbacks = true,
 121         },
 122 };
 123
 124 static struct resource wm8994_codec_resources[] = {
 125         {
 126                 .start = WM8994_IRQ_TEMP_SHUT,
 127                 .end   = WM8994_IRQ_TEMP_WARN,
 128                 .flags = IORESOURCE_IRQ,
 129         },
 130 };
 131
 132 static struct resource wm8994_gpio_resources[] = {
 133         {
 134                 .start = WM8994_IRQ_GPIO(1),
 135                 .end   = WM8994_IRQ_GPIO(11),
 136                 .flags = IORESOURCE_IRQ,
 137         },
 138 };
 139
 140 static struct mfd_cell wm8994_devs[] = {
 141         {
 142                 .name = "wm8994-codec",
 143                 .num_resources = ARRAY_SIZE(wm8994_codec_resources),
 144                 .resources = wm8994_codec_resources,
 145         },
 146
 147         {
 148                 .name = "wm8994-gpio",
 149                 .num_resources = ARRAY_SIZE(wm8994_gpio_resources),
 150                 .resources = wm8994_gpio_resources,
 151                 .pm_runtime_no_callbacks = true,
 152         },
 153 };
 154
 155 /*
 156  * Supplies for the main bulk of CODEC; the LDO supplies are ignored
 157  * and should be handled via the standard regulator API supply
 158  * management.
 159  */
 160 static const char *wm1811_main_supplies[] = {
 161         "DBVDD1",
 162         "DBVDD2",
 163         "DBVDD3",
 164         "DCVDD",
 165         "AVDD1",
 166         "AVDD2",
 167         "CPVDD",
 168         "SPKVDD1",
 169         "SPKVDD2",
 170 };
 171
 172 static const char *wm8994_main_supplies[] = {
 173         "DBVDD",
 174         "DCVDD",
 175         "AVDD1",
 176         "AVDD2",
 177         "CPVDD",
 178         "SPKVDD1",
 179         "SPKVDD2",
 180 };
 181
 182 static const char *wm8958_main_supplies[] = {
 183         "DBVDD1",
 184         "DBVDD2",
 185         "DBVDD3",
 186         "DCVDD",
 187         "AVDD1",
 188         "AVDD2",
 189         "CPVDD",
 190         "SPKVDD1",
 191         "SPKVDD2",
 192 };
 193
 194 #ifdef CONFIG_PM
 195 static int wm8994_suspend(struct device *dev)
 196 {
 197         struct wm8994 *wm8994 = dev_get_drvdata(dev);
 198         int ret;
 199
 200         /* Don't actually go through with the suspend if the CODEC is
 201          * still active (eg, for audio passthrough from CP. */
 202         ret = wm8994_reg_read(wm8994, WM8994_POWER_MANAGEMENT_1);
 203         if (ret < 0) {
 204                 dev_err(dev, "Failed to read power status: %d\n", ret);
 205         } else if (ret & WM8994_VMID_SEL_MASK) {
 206                 dev_dbg(dev, "CODEC still active, ignoring suspend\n");
 207                 return 0;
 208         }
 209
 210         ret = wm8994_reg_read(wm8994, WM8994_POWER_MANAGEMENT_4);
 211         if (ret < 0) {
 212                 dev_err(dev, "Failed to read power status: %d\n", ret);
 213         } else if (ret & (WM8994_AIF2ADCL_ENA | WM8994_AIF2ADCR_ENA |
 214                           WM8994_AIF1ADC2L_ENA | WM8994_AIF1ADC2R_ENA |
 215                           WM8994_AIF1ADC1L_ENA | WM8994_AIF1ADC1R_ENA)) {
 216                 dev_dbg(dev, "CODEC still active, ignoring suspend\n");
 217                 return 0;
 218         }
 219
 220         ret = wm8994_reg_read(wm8994, WM8994_POWER_MANAGEMENT_5);
 221         if (ret < 0) {
 222                 dev_err(dev, "Failed to read power status: %d\n", ret);
 223         } else if (ret & (WM8994_AIF2DACL_ENA | WM8994_AIF2DACR_ENA |
 224                           WM8994_AIF1DAC2L_ENA | WM8994_AIF1DAC2R_ENA |
 225                           WM8994_AIF1DAC1L_ENA | WM8994_AIF1DAC1R_ENA)) {
 226                 dev_dbg(dev, "CODEC still active, ignoring suspend\n");
 227                 return 0;
 228         }
 229
 230         switch (wm8994->type) {
 231         case WM8958:
 232                 ret = wm8994_reg_read(wm8994, WM8958_MIC_DETECT_1);
 233                 if (ret < 0) {
 234                         dev_err(dev, "Failed to read power status: %d\n", ret);
 235                 } else if (ret & WM8958_MICD_ENA) {
 236                         dev_dbg(dev, "CODEC still active, ignoring suspend\n");
 237                         return 0;
 238                 }
 239                 break;
 240         default:
 241                 break;
 242         }
 243
 244         switch (wm8994->type) {
 245         case WM1811:
 246                 ret = wm8994_reg_read(wm8994, WM8994_ANTIPOP_2);
 247                 if (ret < 0) {
 248                         dev_err(dev, "Failed to read jackdet: %d\n", ret);
 249                 } else if (ret & WM1811_JACKDET_MODE_MASK) {
 250                         dev_dbg(dev, "CODEC still active, ignoring suspend\n");
 251                         return 0;
 252                 }
 253                 break;
 254         default:
 255                 break;
 256         }
 257
 258         /* Disable LDO pulldowns while the device is suspended if we
 259          * don't know that something will be driving them. */
 260         if (!wm8994->ldo_ena_always_driven)
 261                 wm8994_set_bits(wm8994, WM8994_PULL_CONTROL_2,
 262                                 WM8994_LDO1ENA_PD | WM8994_LDO2ENA_PD,
 263                                 WM8994_LDO1ENA_PD | WM8994_LDO2ENA_PD);
 264
 265         /* Explicitly put the device into reset in case regulators
 266          * don't get disabled in order to ensure consistent restart.
 267          */
 268         wm8994_reg_write(wm8994, WM8994_SOFTWARE_RESET,
 269                          wm8994_reg_read(wm8994, WM8994_SOFTWARE_RESET));
 270
 271         regcache_mark_dirty(wm8994->regmap);
 272
 273         wm8994->suspended = true;
 274
 275         ret = regulator_bulk_disable(wm8994->num_supplies,
 276                                      wm8994->supplies);
 277         if (ret != 0) {
 278                 dev_err(dev, "Failed to disable supplies: %d\n", ret);
 279                 return ret;
 280         }
 281
 282         return 0;
 283 }
 284
 285 static int wm8994_resume(struct device *dev)
 286 {
 287         struct wm8994 *wm8994 = dev_get_drvdata(dev);
 288         int ret;
 289
 290         /* We may have lied to the PM core about suspending */
 291         if (!wm8994->suspended)
 292                 return 0;
 293
 294         ret = regulator_bulk_enable(wm8994->num_supplies,
 295                                     wm8994->supplies);
 296         if (ret != 0) {
 297                 dev_err(dev, "Failed to enable supplies: %d\n", ret);
 298                 return ret;
 299         }
 300
 301         ret = regcache_sync(wm8994->regmap);
 302         if (ret != 0) {
 303                 dev_err(dev, "Failed to restore register map: %d\n", ret);
 304                 goto err_enable;
 305         }
 306
 307         /* Disable LDO pulldowns while the device is active */
 308         wm8994_set_bits(wm8994, WM8994_PULL_CONTROL_2,
 309                         WM8994_LDO1ENA_PD | WM8994_LDO2ENA_PD,
 310                         0);
 311
 312         wm8994->suspended = false;
 313
 314         return 0;
 315
 316 err_enable:
 317         regulator_bulk_disable(wm8994->num_supplies, wm8994->supplies);
 318
 319         return ret;
 320 }
 321 #endif
 322
 323 #ifdef CONFIG_REGULATOR
 324 static int wm8994_ldo_in_use(struct wm8994_pdata *pdata, int ldo)
 325 {
 326         struct wm8994_ldo_pdata *ldo_pdata;
 327
 328         if (!pdata)
 329                 return 0;
 330
 331         ldo_pdata = &pdata->ldo[ldo];
 332
 333         if (!ldo_pdata->init_data)
 334                 return 0;
 335
 336         return ldo_pdata->init_data->num_consumer_supplies != 0;
 337 }
 338 #else
 339 static int wm8994_ldo_in_use(struct wm8994_pdata *pdata, int ldo)
 340 {
 341         return 0;
 342 }
 343 #endif
 344
 345 /*
 346  * Instantiate the generic non-control parts of the device.
 347  */
 348 static int wm8994_device_init(struct wm8994 *wm8994, int irq)
 349 {
 350         struct wm8994_pdata *pdata = wm8994->dev->platform_data;
 351         struct regmap_config *regmap_config;
 352         const char *devname;
 353         int ret, i;
 354         int pulls = 0;
 355
 356         dev_set_drvdata(wm8994->dev, wm8994);
 357
 358         /* Add the on-chip regulators first for bootstrapping */
 359         ret = mfd_add_devices(wm8994->dev, -1,
 360                               wm8994_regulator_devs,
 361                               ARRAY_SIZE(wm8994_regulator_devs),
 362                               NULL, 0);
 363         if (ret != 0) {
 364                 dev_err(wm8994->dev, "Failed to add children: %d\n", ret);
 365                 goto err_regmap;
 366         }
 367
 368         switch (wm8994->type) {
 369         case WM1811:
 370                 wm8994->num_supplies = ARRAY_SIZE(wm1811_main_supplies);
 371                 break;
 372         case WM8994:
 373                 wm8994->num_supplies = ARRAY_SIZE(wm8994_main_supplies);
 374                 break;
 375         case WM8958:
 376                 wm8994->num_supplies = ARRAY_SIZE(wm8958_main_supplies);
 377                 break;
 378         default:
 379                 BUG();
 380                 goto err_regmap;
 381         }
 382
 383         wm8994->supplies = devm_kzalloc(wm8994->dev,
 384                                         sizeof(struct regulator_bulk_data) *
 385                                         wm8994->num_supplies, GFP_KERNEL);
 386         if (!wm8994->supplies) {
 387                 ret = -ENOMEM;
 388                 goto err_regmap;
 389         }
 390
 391         switch (wm8994->type) {
 392         case WM1811:
 393                 for (i = 0; i < ARRAY_SIZE(wm1811_main_supplies); i++)
 394                         wm8994->supplies[i].supply = wm1811_main_supplies[i];
 395                 break;
 396         case WM8994:
 397                 for (i = 0; i < ARRAY_SIZE(wm8994_main_supplies); i++)
 398                         wm8994->supplies[i].supply = wm8994_main_supplies[i];
 399                 break;
 400         case WM8958:
 401                 for (i = 0; i < ARRAY_SIZE(wm8958_main_supplies); i++)
 402                         wm8994->supplies[i].supply = wm8958_main_supplies[i];
 403                 break;
 404         default:
 405                 BUG();
 406                 goto err_regmap;
 407         }
 408
 409         ret = regulator_bulk_get(wm8994->dev, wm8994->num_supplies,
 410                                  wm8994->supplies);
 411         if (ret != 0) {
 412                 dev_err(wm8994->dev, "Failed to get supplies: %d\n", ret);
 413                 goto err_regmap;
 414         }
 415
 416         ret = regulator_bulk_enable(wm8994->num_supplies,
 417                                     wm8994->supplies);
 418         if (ret != 0) {
 419                 dev_err(wm8994->dev, "Failed to enable supplies: %d\n", ret);
 420                 goto err_get;
 421         }
 422
 423         ret = wm8994_reg_read(wm8994, WM8994_SOFTWARE_RESET);
 424         if (ret < 0) {
 425                 dev_err(wm8994->dev, "Failed to read ID register\n");
 426                 goto err_enable;
 427         }
 428         switch (ret) {
 429         case 0x1811:
 430                 devname = "WM1811";
 431                 if (wm8994->type != WM1811)
 432                         dev_warn(wm8994->dev, "Device registered as type %d\n",
 433                                  wm8994->type);
 434                 wm8994->type = WM1811;
 435                 break;
 436         case 0x8994:
 437                 devname = "WM8994";
 438                 if (wm8994->type != WM8994)
 439                         dev_warn(wm8994->dev, "Device registered as type %d\n",
 440                                  wm8994->type);
 441                 wm8994->type = WM8994;
 442                 break;
 443         case 0x8958:
 444                 devname = "WM8958";
 445                 if (wm8994->type != WM8958)
 446                         dev_warn(wm8994->dev, "Device registered as type %d\n",
 447                                  wm8994->type);
 448                 wm8994->type = WM8958;
 449                 break;
 450         default:
 451                 dev_err(wm8994->dev, "Device is not a WM8994, ID is %x\n",
 452                         ret);
 453                 ret = -EINVAL;
 454                 goto err_enable;
 455         }
 456
 457         ret = wm8994_reg_read(wm8994, WM8994_CHIP_REVISION);
 458         if (ret < 0) {
 459                 dev_err(wm8994->dev, "Failed to read revision register: %d\n",
 460                         ret);
 461                 goto err_enable;
 462         }
 463         wm8994->revision = ret;
 464
 465         switch (wm8994->type) {
 466         case WM8994:
 467                 switch (wm8994->revision) {
 468                 case 0:
 469                 case 1:
 470                         dev_warn(wm8994->dev,
 471                                  "revision %c not fully supported\n",
 472                                  'A' + wm8994->revision);
 473                         break;
 474                 default:
 475                         break;
 476                 }
 477                 break;
 478         case WM1811:
 479                 /* Revision C did not change the relevant layer */
 480                 if (wm8994->revision > 1)
 481                         wm8994->revision++;
 482                 break;
 483         default:
 484                 break;
 485         }
 486
 487         dev_info(wm8994->dev, "%s revision %c\n", devname,
 488                  'A' + wm8994->revision);
 489
 490         switch (wm8994->type) {
 491         case WM1811:
 492                 regmap_config = &wm1811_regmap_config;
 493                 break;
 494         case WM8994:
 495                 regmap_config = &wm8994_regmap_config;
 496                 break;
 497         case WM8958:
 498                 regmap_config = &wm8958_regmap_config;
 499                 break;
 500         default:
 501                 dev_err(wm8994->dev, "Unknown device type %d\n", wm8994->type);
 502                 return -EINVAL;
 503         }
 504
 505         ret = regmap_reinit_cache(wm8994->regmap, regmap_config);
 506         if (ret != 0) {
 507                 dev_err(wm8994->dev, "Failed to reinit register cache: %d\n",
 508                         ret);
 509                 return ret;
 510         }
 511
 512         if (pdata) {
 513                 wm8994->irq_base = pdata->irq_base;
 514                 wm8994->gpio_base = pdata->gpio_base;
 515
 516                 /* GPIO configuration is only applied if it's non-zero */
 517                 for (i = 0; i < ARRAY_SIZE(pdata->gpio_defaults); i++) {
 518                         if (pdata->gpio_defaults[i]) {
 519                                 wm8994_set_bits(wm8994, WM8994_GPIO_1 + i,
 520                                                 0xffff,
 521                                                 pdata->gpio_defaults[i]);
 522                         }
 523                 }
 524
 525                 wm8994->ldo_ena_always_driven = pdata->ldo_ena_always_driven;
 526
 527                 if (pdata->spkmode_pu)
 528                         pulls |= WM8994_SPKMODE_PU;
 529         }
 530
 531         /* Disable unneeded pulls */
 532         wm8994_set_bits(wm8994, WM8994_PULL_CONTROL_2,
 533                         WM8994_LDO1ENA_PD | WM8994_LDO2ENA_PD |
 534                         WM8994_SPKMODE_PU | WM8994_CSNADDR_PD,
 535                         pulls);
 536
 537         /* In some system designs where the regulators are not in use,
 538          * we can achieve a small reduction in leakage currents by
 539          * floating LDO outputs.  This bit makes no difference if the
 540          * LDOs are enabled, it only affects cases where the LDOs were
 541          * in operation and are then disabled.
 542          */
 543         for (i = 0; i < WM8994_NUM_LDO_REGS; i++) {
 544                 if (wm8994_ldo_in_use(pdata, i))
 545                         wm8994_set_bits(wm8994, WM8994_LDO_1 + i,
 546                                         WM8994_LDO1_DISCH, WM8994_LDO1_DISCH);
 547                 else
 548                         wm8994_set_bits(wm8994, WM8994_LDO_1 + i,
 549                                         WM8994_LDO1_DISCH, 0);
 550         }
 551
 552         wm8994_irq_init(wm8994);
 553
 554         ret = mfd_add_devices(wm8994->dev, -1,
 555                               wm8994_devs, ARRAY_SIZE(wm8994_devs),
 556                               NULL, 0);
 557         if (ret != 0) {
 558                 dev_err(wm8994->dev, "Failed to add children: %d\n", ret);
 559                 goto err_irq;
 560         }
 561
 562         pm_runtime_enable(wm8994->dev);
 563         pm_runtime_resume(wm8994->dev);
 564
 565         return 0;
 566
 567 err_irq:
 568         wm8994_irq_exit(wm8994);
 569 err_enable:
 570         regulator_bulk_disable(wm8994->num_supplies,
 571                                wm8994->supplies);
 572 err_get:
 573         regulator_bulk_free(wm8994->num_supplies, wm8994->supplies);
 574 err_regmap:
 575         regmap_exit(wm8994->regmap);
 576         mfd_remove_devices(wm8994->dev);
 577         return ret;
 578 }
 579
 580 static void wm8994_device_exit(struct wm8994 *wm8994)
 581 {
 582         pm_runtime_disable(wm8994->dev);
 583         mfd_remove_devices(wm8994->dev);
 584         wm8994_irq_exit(wm8994);
 585         regulator_bulk_disable(wm8994->num_supplies,
 586                                wm8994->supplies);
 587         regulator_bulk_free(wm8994->num_supplies, wm8994->supplies);
 588         regmap_exit(wm8994->regmap);
 589 }
 590
 591 static const struct of_device_id wm8994_of_match[] = {
 592         { .compatible = "wlf,wm1811", },
 593         { .compatible = "wlf,wm8994", },
 594         { .compatible = "wlf,wm8958", },
 595         { }
 596 };
 597 MODULE_DEVICE_TABLE(of, wm8994_of_match);
 598
 599 static int wm8994_i2c_probe(struct i2c_client *i2c,
 600                             const struct i2c_device_id *id)
 601 {
 602         struct wm8994 *wm8994;
 603         int ret;
 604
 605         wm8994 = devm_kzalloc(&i2c->dev, sizeof(struct wm8994), GFP_KERNEL);
 606         if (wm8994 == NULL)
 607                 return -ENOMEM;
 608
 609         i2c_set_clientdata(i2c, wm8994);
 610         wm8994->dev = &i2c->dev;
 611         wm8994->irq = i2c->irq;
 612         wm8994->type = id->driver_data;
 613
 614         wm8994->regmap = regmap_init_i2c(i2c, &wm8994_base_regmap_config);
 615         if (IS_ERR(wm8994->regmap)) {
 616                 ret = PTR_ERR(wm8994->regmap);
 617                 dev_err(wm8994->dev, "Failed to allocate register map: %d\n",
 618                         ret);
 619                 return ret;
 620         }
 621
 622         return wm8994_device_init(wm8994, i2c->irq);
 623 }
 624
 625 static int wm8994_i2c_remove(struct i2c_client *i2c)
 626 {
 627         struct wm8994 *wm8994 = i2c_get_clientdata(i2c);
 628
 629         wm8994_device_exit(wm8994);
 630
 631         return 0;
 632 }
 633
 634 static const struct i2c_device_id wm8994_i2c_id[] = {
 635         { "wm1811", WM1811 },
 636         { "wm1811a", WM1811 },
 637         { "wm8994", WM8994 },
 638         { "wm8958", WM8958 },
 639         { }
 640 };
 641 MODULE_DEVICE_TABLE(i2c, wm8994_i2c_id);
 642
 643 static UNIVERSAL_DEV_PM_OPS(wm8994_pm_ops, wm8994_suspend, wm8994_resume,
 644                             NULL);
 645
 646 static struct i2c_driver wm8994_i2c_driver = {
 647         .driver = {
 648                 .name = "wm8994",
 649                 .owner = THIS_MODULE,
 650                 .pm = &wm8994_pm_ops,
 651                 .of_match_table = wm8994_of_match,
 652         },
 653         .probe = wm8994_i2c_probe,
 654         .remove = wm8994_i2c_remove,
 655         .id_table = wm8994_i2c_id,
 656 };
 657
 658 static int __init wm8994_i2c_init(void)
 659 {
 660         int ret;
 661
 662         ret = i2c_add_driver(&wm8994_i2c_driver);
 663         if (ret != 0)
 664                 pr_err("Failed to register wm8994 I2C driver: %d\n", ret);
 665
 666         return ret;
 667 }
 668 module_init(wm8994_i2c_init);
 669
 670 static void __exit wm8994_i2c_exit(void)
 671 {
 672         i2c_del_driver(&wm8994_i2c_driver);
 673 }
 674 module_exit(wm8994_i2c_exit);
 675
 676 MODULE_DESCRIPTION("Core support for the WM8994 audio CODEC");
 677 MODULE_LICENSE("GPL");
 678 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");