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         case WM1811:
 233                 ret = wm8994_reg_read(wm8994, WM8958_MIC_DETECT_1);
 234                 if (ret < 0) {
 235                         dev_err(dev, "Failed to read power status: %d\n", ret);
 236                 } else if (ret & WM8958_MICD_ENA) {
 237                         dev_dbg(dev, "CODEC still active, ignoring suspend\n");
 238                         return 0;
 239                 }
 240                 break;
 241         default:
 242                 break;
 243         }
 244
 245         switch (wm8994->type) {
 246         case WM1811:
 247                 ret = wm8994_reg_read(wm8994, WM8994_ANTIPOP_2);
 248                 if (ret < 0) {
 249                         dev_err(dev, "Failed to read jackdet: %d\n", ret);
 250                 } else if (ret & WM1811_JACKDET_MODE_MASK) {
 251                         dev_dbg(dev, "CODEC still active, ignoring suspend\n");
 252                         return 0;
 253                 }
 254                 break;
 255         default:
 256                 break;
 257         }
 258
 259         switch (wm8994->type) {
 260         case WM1811:
 261                 ret = wm8994_reg_read(wm8994, WM8994_ANTIPOP_2);
 262                 if (ret < 0) {
 263                         dev_err(dev, "Failed to read jackdet: %d\n", ret);
 264                 } else if (ret & WM1811_JACKDET_MODE_MASK) {
 265                         dev_dbg(dev, "CODEC still active, ignoring suspend\n");
 266                         return 0;
 267                 }
 268                 break;
 269         default:
 270                 break;
 271         }
 272
 273         /* Disable LDO pulldowns while the device is suspended if we
 274          * don't know that something will be driving them. */
 275         if (!wm8994->ldo_ena_always_driven)
 276                 wm8994_set_bits(wm8994, WM8994_PULL_CONTROL_2,
 277                                 WM8994_LDO1ENA_PD | WM8994_LDO2ENA_PD,
 278                                 WM8994_LDO1ENA_PD | WM8994_LDO2ENA_PD);
 279
 280         /* Explicitly put the device into reset in case regulators
 281          * don't get disabled in order to ensure consistent restart.
 282          */
 283         wm8994_reg_write(wm8994, WM8994_SOFTWARE_RESET,
 284                          wm8994_reg_read(wm8994, WM8994_SOFTWARE_RESET));
 285
 286         regcache_cache_only(wm8994->regmap, true);
 287         regcache_mark_dirty(wm8994->regmap);
 288
 289         wm8994->suspended = true;
 290
 291         ret = regulator_bulk_disable(wm8994->num_supplies,
 292                                      wm8994->supplies);
 293         if (ret != 0) {
 294                 dev_err(dev, "Failed to disable supplies: %d\n", ret);
 295                 return ret;
 296         }
 297
 298         return 0;
 299 }
 300
 301 static int wm8994_resume(struct device *dev)
 302 {
 303         struct wm8994 *wm8994 = dev_get_drvdata(dev);
 304         int ret;
 305
 306         /* We may have lied to the PM core about suspending */
 307         if (!wm8994->suspended)
 308                 return 0;
 309
 310         ret = regulator_bulk_enable(wm8994->num_supplies,
 311                                     wm8994->supplies);
 312         if (ret != 0) {
 313                 dev_err(dev, "Failed to enable supplies: %d\n", ret);
 314                 return ret;
 315         }
 316
 317         regcache_cache_only(wm8994->regmap, false);
 318         ret = regcache_sync(wm8994->regmap);
 319         if (ret != 0) {
 320                 dev_err(dev, "Failed to restore register map: %d\n", ret);
 321                 goto err_enable;
 322         }
 323
 324         /* Disable LDO pulldowns while the device is active */
 325         wm8994_set_bits(wm8994, WM8994_PULL_CONTROL_2,
 326                         WM8994_LDO1ENA_PD | WM8994_LDO2ENA_PD,
 327                         0);
 328
 329         wm8994->suspended = false;
 330
 331         return 0;
 332
 333 err_enable:
 334         regulator_bulk_disable(wm8994->num_supplies, wm8994->supplies);
 335
 336         return ret;
 337 }
 338 #endif
 339
 340 #ifdef CONFIG_REGULATOR
 341 static int wm8994_ldo_in_use(struct wm8994_pdata *pdata, int ldo)
 342 {
 343         struct wm8994_ldo_pdata *ldo_pdata;
 344
 345         if (!pdata)
 346                 return 0;
 347
 348         ldo_pdata = &pdata->ldo[ldo];
 349
 350         if (!ldo_pdata->init_data)
 351                 return 0;
 352
 353         return ldo_pdata->init_data->num_consumer_supplies != 0;
 354 }
 355 #else
 356 static int wm8994_ldo_in_use(struct wm8994_pdata *pdata, int ldo)
 357 {
 358         return 0;
 359 }
 360 #endif
 361
 362 /*
 363  * Instantiate the generic non-control parts of the device.
 364  */
 365 static int wm8994_device_init(struct wm8994 *wm8994, int irq)
 366 {
 367         struct wm8994_pdata *pdata = wm8994->dev->platform_data;
 368         struct regmap_config *regmap_config;
 369         const char *devname;
 370         int ret, i;
 371         int pulls = 0;
 372
 373         dev_set_drvdata(wm8994->dev, wm8994);
 374
 375         /* Add the on-chip regulators first for bootstrapping */
 376         ret = mfd_add_devices(wm8994->dev, -1,
 377                               wm8994_regulator_devs,
 378                               ARRAY_SIZE(wm8994_regulator_devs),
 379                               NULL, 0);
 380         if (ret != 0) {
 381                 dev_err(wm8994->dev, "Failed to add children: %d\n", ret);
 382                 goto err_regmap;
 383         }
 384
 385         switch (wm8994->type) {
 386         case WM1811:
 387                 wm8994->num_supplies = ARRAY_SIZE(wm1811_main_supplies);
 388                 break;
 389         case WM8994:
 390                 wm8994->num_supplies = ARRAY_SIZE(wm8994_main_supplies);
 391                 break;
 392         case WM8958:
 393                 wm8994->num_supplies = ARRAY_SIZE(wm8958_main_supplies);
 394                 break;
 395         default:
 396                 BUG();
 397                 goto err_regmap;
 398         }
 399
 400         wm8994->supplies = devm_kzalloc(wm8994->dev,
 401                                         sizeof(struct regulator_bulk_data) *
 402                                         wm8994->num_supplies, GFP_KERNEL);
 403         if (!wm8994->supplies) {
 404                 ret = -ENOMEM;
 405                 goto err_regmap;
 406         }
 407
 408         switch (wm8994->type) {
 409         case WM1811:
 410                 for (i = 0; i < ARRAY_SIZE(wm1811_main_supplies); i++)
 411                         wm8994->supplies[i].supply = wm1811_main_supplies[i];
 412                 break;
 413         case WM8994:
 414                 for (i = 0; i < ARRAY_SIZE(wm8994_main_supplies); i++)
 415                         wm8994->supplies[i].supply = wm8994_main_supplies[i];
 416                 break;
 417         case WM8958:
 418                 for (i = 0; i < ARRAY_SIZE(wm8958_main_supplies); i++)
 419                         wm8994->supplies[i].supply = wm8958_main_supplies[i];
 420                 break;
 421         default:
 422                 BUG();
 423                 goto err_regmap;
 424         }
 425
 426         ret = regulator_bulk_get(wm8994->dev, wm8994->num_supplies,
 427                                  wm8994->supplies);
 428         if (ret != 0) {
 429                 dev_err(wm8994->dev, "Failed to get supplies: %d\n", ret);
 430                 goto err_regmap;
 431         }
 432
 433         ret = regulator_bulk_enable(wm8994->num_supplies,
 434                                     wm8994->supplies);
 435         if (ret != 0) {
 436                 dev_err(wm8994->dev, "Failed to enable supplies: %d\n", ret);
 437                 goto err_get;
 438         }
 439
 440         ret = wm8994_reg_read(wm8994, WM8994_SOFTWARE_RESET);
 441         if (ret < 0) {
 442                 dev_err(wm8994->dev, "Failed to read ID register\n");
 443                 goto err_enable;
 444         }
 445         switch (ret) {
 446         case 0x1811:
 447                 devname = "WM1811";
 448                 if (wm8994->type != WM1811)
 449                         dev_warn(wm8994->dev, "Device registered as type %d\n",
 450                                  wm8994->type);
 451                 wm8994->type = WM1811;
 452                 break;
 453         case 0x8994:
 454                 devname = "WM8994";
 455                 if (wm8994->type != WM8994)
 456                         dev_warn(wm8994->dev, "Device registered as type %d\n",
 457                                  wm8994->type);
 458                 wm8994->type = WM8994;
 459                 break;
 460         case 0x8958:
 461                 devname = "WM8958";
 462                 if (wm8994->type != WM8958)
 463                         dev_warn(wm8994->dev, "Device registered as type %d\n",
 464                                  wm8994->type);
 465                 wm8994->type = WM8958;
 466                 break;
 467         default:
 468                 dev_err(wm8994->dev, "Device is not a WM8994, ID is %x\n",
 469                         ret);
 470                 ret = -EINVAL;
 471                 goto err_enable;
 472         }
 473
 474         ret = wm8994_reg_read(wm8994, WM8994_CHIP_REVISION);
 475         if (ret < 0) {
 476                 dev_err(wm8994->dev, "Failed to read revision register: %d\n",
 477                         ret);
 478                 goto err_enable;
 479         }
 480         wm8994->revision = ret;
 481
 482         switch (wm8994->type) {
 483         case WM8994:
 484                 switch (wm8994->revision) {
 485                 case 0:
 486                 case 1:
 487                         dev_warn(wm8994->dev,
 488                                  "revision %c not fully supported\n",
 489                                  'A' + wm8994->revision);
 490                         break;
 491                 default:
 492                         break;
 493                 }
 494                 break;
 495         case WM1811:
 496                 /* Revision C did not change the relevant layer */
 497                 if (wm8994->revision > 1)
 498                         wm8994->revision++;
 499                 break;
 500         default:
 501                 break;
 502         }
 503
 504         dev_info(wm8994->dev, "%s revision %c\n", devname,
 505                  'A' + wm8994->revision);
 506
 507         switch (wm8994->type) {
 508         case WM1811:
 509                 regmap_config = &wm1811_regmap_config;
 510                 break;
 511         case WM8994:
 512                 regmap_config = &wm8994_regmap_config;
 513                 break;
 514         case WM8958:
 515                 regmap_config = &wm8958_regmap_config;
 516                 break;
 517         default:
 518                 dev_err(wm8994->dev, "Unknown device type %d\n", wm8994->type);
 519                 return -EINVAL;
 520         }
 521
 522         ret = regmap_reinit_cache(wm8994->regmap, regmap_config);
 523         if (ret != 0) {
 524                 dev_err(wm8994->dev, "Failed to reinit register cache: %d\n",
 525                         ret);
 526                 return ret;
 527         }
 528
 529         if (pdata) {
 530                 wm8994->irq_base = pdata->irq_base;
 531                 wm8994->gpio_base = pdata->gpio_base;
 532
 533                 /* GPIO configuration is only applied if it's non-zero */
 534                 for (i = 0; i < ARRAY_SIZE(pdata->gpio_defaults); i++) {
 535                         if (pdata->gpio_defaults[i]) {
 536                                 wm8994_set_bits(wm8994, WM8994_GPIO_1 + i,
 537                                                 0xffff,
 538                                                 pdata->gpio_defaults[i]);
 539                         }
 540                 }
 541
 542                 wm8994->ldo_ena_always_driven = pdata->ldo_ena_always_driven;
 543
 544                 if (pdata->spkmode_pu)
 545                         pulls |= WM8994_SPKMODE_PU;
 546         }
 547
 548         /* Disable unneeded pulls */
 549         wm8994_set_bits(wm8994, WM8994_PULL_CONTROL_2,
 550                         WM8994_LDO1ENA_PD | WM8994_LDO2ENA_PD |
 551                         WM8994_SPKMODE_PU | WM8994_CSNADDR_PD,
 552                         pulls);
 553
 554         /* In some system designs where the regulators are not in use,
 555          * we can achieve a small reduction in leakage currents by
 556          * floating LDO outputs.  This bit makes no difference if the
 557          * LDOs are enabled, it only affects cases where the LDOs were
 558          * in operation and are then disabled.
 559          */
 560         for (i = 0; i < WM8994_NUM_LDO_REGS; i++) {
 561                 if (wm8994_ldo_in_use(pdata, i))
 562                         wm8994_set_bits(wm8994, WM8994_LDO_1 + i,
 563                                         WM8994_LDO1_DISCH, WM8994_LDO1_DISCH);
 564                 else
 565                         wm8994_set_bits(wm8994, WM8994_LDO_1 + i,
 566                                         WM8994_LDO1_DISCH, 0);
 567         }
 568
 569         wm8994_irq_init(wm8994);
 570
 571         ret = mfd_add_devices(wm8994->dev, -1,
 572                               wm8994_devs, ARRAY_SIZE(wm8994_devs),
 573                               NULL, 0);
 574         if (ret != 0) {
 575                 dev_err(wm8994->dev, "Failed to add children: %d\n", ret);
 576                 goto err_irq;
 577         }
 578
 579         pm_runtime_enable(wm8994->dev);
 580         pm_runtime_resume(wm8994->dev);
 581
 582         return 0;
 583
 584 err_irq:
 585         wm8994_irq_exit(wm8994);
 586 err_enable:
 587         regulator_bulk_disable(wm8994->num_supplies,
 588                                wm8994->supplies);
 589 err_get:
 590         regulator_bulk_free(wm8994->num_supplies, wm8994->supplies);
 591 err_regmap:
 592         regmap_exit(wm8994->regmap);
 593         mfd_remove_devices(wm8994->dev);
 594         return ret;
 595 }
 596
 597 static void wm8994_device_exit(struct wm8994 *wm8994)
 598 {
 599         pm_runtime_disable(wm8994->dev);
 600         mfd_remove_devices(wm8994->dev);
 601         wm8994_irq_exit(wm8994);
 602         regulator_bulk_disable(wm8994->num_supplies,
 603                                wm8994->supplies);
 604         regulator_bulk_free(wm8994->num_supplies, wm8994->supplies);
 605         regmap_exit(wm8994->regmap);
 606 }
 607
 608 static const struct of_device_id wm8994_of_match[] = {
 609         { .compatible = "wlf,wm1811", },
 610         { .compatible = "wlf,wm8994", },
 611         { .compatible = "wlf,wm8958", },
 612         { }
 613 };
 614 MODULE_DEVICE_TABLE(of, wm8994_of_match);
 615
 616 static int wm8994_i2c_probe(struct i2c_client *i2c,
 617                             const struct i2c_device_id *id)
 618 {
 619         struct wm8994 *wm8994;
 620         int ret;
 621
 622         wm8994 = devm_kzalloc(&i2c->dev, sizeof(struct wm8994), GFP_KERNEL);
 623         if (wm8994 == NULL)
 624                 return -ENOMEM;
 625
 626         i2c_set_clientdata(i2c, wm8994);
 627         wm8994->dev = &i2c->dev;
 628         wm8994->irq = i2c->irq;
 629         wm8994->type = id->driver_data;
 630
 631         wm8994->regmap = regmap_init_i2c(i2c, &wm8994_base_regmap_config);
 632         if (IS_ERR(wm8994->regmap)) {
 633                 ret = PTR_ERR(wm8994->regmap);
 634                 dev_err(wm8994->dev, "Failed to allocate register map: %d\n",
 635                         ret);
 636                 return ret;
 637         }
 638
 639         return wm8994_device_init(wm8994, i2c->irq);
 640 }
 641
 642 static int wm8994_i2c_remove(struct i2c_client *i2c)
 643 {
 644         struct wm8994 *wm8994 = i2c_get_clientdata(i2c);
 645
 646         wm8994_device_exit(wm8994);
 647
 648         return 0;
 649 }
 650
 651 static const struct i2c_device_id wm8994_i2c_id[] = {
 652         { "wm1811", WM1811 },
 653         { "wm1811a", WM1811 },
 654         { "wm8994", WM8994 },
 655         { "wm8958", WM8958 },
 656         { }
 657 };
 658 MODULE_DEVICE_TABLE(i2c, wm8994_i2c_id);
 659
 660 static UNIVERSAL_DEV_PM_OPS(wm8994_pm_ops, wm8994_suspend, wm8994_resume,
 661                             NULL);
 662
 663 static struct i2c_driver wm8994_i2c_driver = {
 664         .driver = {
 665                 .name = "wm8994",
 666                 .owner = THIS_MODULE,
 667                 .pm = &wm8994_pm_ops,
 668                 .of_match_table = wm8994_of_match,
 669         },
 670         .probe = wm8994_i2c_probe,
 671         .remove = wm8994_i2c_remove,
 672         .id_table = wm8994_i2c_id,
 673 };
 674
 675 static int __init wm8994_i2c_init(void)
 676 {
 677         int ret;
 678
 679         ret = i2c_add_driver(&wm8994_i2c_driver);
 680         if (ret != 0)
 681                 pr_err("Failed to register wm8994 I2C driver: %d\n", ret);
 682
 683         return ret;
 684 }
 685 module_init(wm8994_i2c_init);
 686
 687 static void __exit wm8994_i2c_exit(void)
 688 {
 689         i2c_del_driver(&wm8994_i2c_driver);
 690 }
 691 module_exit(wm8994_i2c_exit);
 692
 693 MODULE_DESCRIPTION("Core support for the WM8994 audio CODEC");
 694 MODULE_LICENSE("GPL");
 695 MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");