drivers/iio/dac/ad5064.c

   1 /*
   2  * AD5024, AD5025, AD5044, AD5045, AD5064, AD5064-1, AD5065, AD5628, AD5629R,
   3  * AD5648, AD5666, AD5668, AD5669R Digital to analog converters driver
   4  *
   5  * Copyright 2011 Analog Devices Inc.
   6  *
   7  * Licensed under the GPL-2.
   8  */
   9
  10 #include <linux/device.h>
  11 #include <linux/err.h>
  12 #include <linux/module.h>
  13 #include <linux/kernel.h>
  14 #include <linux/spi/spi.h>
  15 #include <linux/i2c.h>
  16 #include <linux/slab.h>
  17 #include <linux/sysfs.h>
  18 #include <linux/regulator/consumer.h>
  19 #include <asm/unaligned.h>
  20
  21 #include <linux/iio/iio.h>
  22 #include <linux/iio/sysfs.h>
  23
  24 #define AD5064_MAX_DAC_CHANNELS                 8
  25 #define AD5064_MAX_VREFS                        4
  26
  27 #define AD5064_ADDR(x)                          ((x) << 20)
  28 #define AD5064_CMD(x)                           ((x) << 24)
  29
  30 #define AD5064_ADDR_ALL_DAC                     0xF
  31
  32 #define AD5064_CMD_WRITE_INPUT_N                0x0
  33 #define AD5064_CMD_UPDATE_DAC_N                 0x1
  34 #define AD5064_CMD_WRITE_INPUT_N_UPDATE_ALL     0x2
  35 #define AD5064_CMD_WRITE_INPUT_N_UPDATE_N       0x3
  36 #define AD5064_CMD_POWERDOWN_DAC                0x4
  37 #define AD5064_CMD_CLEAR                        0x5
  38 #define AD5064_CMD_LDAC_MASK                    0x6
  39 #define AD5064_CMD_RESET                        0x7
  40 #define AD5064_CMD_CONFIG                       0x8
  41
  42 #define AD5064_CONFIG_DAISY_CHAIN_ENABLE        BIT(1)
  43 #define AD5064_CONFIG_INT_VREF_ENABLE           BIT(0)
  44
  45 #define AD5064_LDAC_PWRDN_NONE                  0x0
  46 #define AD5064_LDAC_PWRDN_1K                    0x1
  47 #define AD5064_LDAC_PWRDN_100K                  0x2
  48 #define AD5064_LDAC_PWRDN_3STATE                0x3
  49
  50 /**
  51  * struct ad5064_chip_info - chip specific information
  52  * @shared_vref:        whether the vref supply is shared between channels
  53  * @internal_vref:      internal reference voltage. 0 if the chip has no internal
  54  *                      vref.
  55  * @channel:            channel specification
  56  * @num_channels:       number of channels
  57  */
  58
  59 struct ad5064_chip_info {
  60         bool shared_vref;
  61         unsigned long internal_vref;
  62         const struct iio_chan_spec *channels;
  63         unsigned int num_channels;
  64 };
  65
  66 struct ad5064_state;
  67
  68 typedef int (*ad5064_write_func)(struct ad5064_state *st, unsigned int cmd,
  69                 unsigned int addr, unsigned int val);
  70
  71 /**
  72  * struct ad5064_state - driver instance specific data
  73  * @dev:                the device for this driver instance
  74  * @chip_info:          chip model specific constants, available modes etc
  75  * @vref_reg:           vref supply regulators
  76  * @pwr_down:           whether channel is powered down
  77  * @pwr_down_mode:      channel's current power down mode
  78  * @dac_cache:          current DAC raw value (chip does not support readback)
  79  * @use_internal_vref:  set to true if the internal reference voltage should be
  80  *                      used.
  81  * @write:              register write callback
  82  * @data:               i2c/spi transfer buffers
  83  */
  84
  85 struct ad5064_state {
  86         struct device                   *dev;
  87         const struct ad5064_chip_info   *chip_info;
  88         struct regulator_bulk_data      vref_reg[AD5064_MAX_VREFS];
  89         bool                            pwr_down[AD5064_MAX_DAC_CHANNELS];
  90         u8                              pwr_down_mode[AD5064_MAX_DAC_CHANNELS];
  91         unsigned int                    dac_cache[AD5064_MAX_DAC_CHANNELS];
  92         bool                            use_internal_vref;
  93
  94         ad5064_write_func               write;
  95
  96         /*
  97          * DMA (thus cache coherency maintenance) requires the
  98          * transfer buffers to live in their own cache lines.
  99          */
 100         union {
 101                 u8 i2c[3];
 102                 __be32 spi;
 103         } data ____cacheline_aligned;
 104 };
 105
 106 enum ad5064_type {
 107         ID_AD5024,
 108         ID_AD5025,
 109         ID_AD5044,
 110         ID_AD5045,
 111         ID_AD5064,
 112         ID_AD5064_1,
 113         ID_AD5065,
 114         ID_AD5628_1,
 115         ID_AD5628_2,
 116         ID_AD5648_1,
 117         ID_AD5648_2,
 118         ID_AD5666_1,
 119         ID_AD5666_2,
 120         ID_AD5668_1,
 121         ID_AD5668_2,
 122 };
 123
 124 static int ad5064_write(struct ad5064_state *st, unsigned int cmd,
 125         unsigned int addr, unsigned int val, unsigned int shift)
 126 {
 127         val <<= shift;
 128
 129         return st->write(st, cmd, addr, val);
 130 }
 131
 132 static int ad5064_sync_powerdown_mode(struct ad5064_state *st,
 133         const struct iio_chan_spec *chan)
 134 {
 135         unsigned int val;
 136         int ret;
 137
 138         val = (0x1 << chan->address);
 139
 140         if (st->pwr_down[chan->channel])
 141                 val |= st->pwr_down_mode[chan->channel] << 8;
 142
 143         ret = ad5064_write(st, AD5064_CMD_POWERDOWN_DAC, 0, val, 0);
 144
 145         return ret;
 146 }
 147
 148 static const char * const ad5064_powerdown_modes[] = {
 149         "1kohm_to_gnd",
 150         "100kohm_to_gnd",
 151         "three_state",
 152 };
 153
 154 static int ad5064_get_powerdown_mode(struct iio_dev *indio_dev,
 155         const struct iio_chan_spec *chan)
 156 {
 157         struct ad5064_state *st = iio_priv(indio_dev);
 158
 159         return st->pwr_down_mode[chan->channel] - 1;
 160 }
 161
 162 static int ad5064_set_powerdown_mode(struct iio_dev *indio_dev,
 163         const struct iio_chan_spec *chan, unsigned int mode)
 164 {
 165         struct ad5064_state *st = iio_priv(indio_dev);
 166         int ret;
 167
 168         mutex_lock(&indio_dev->mlock);
 169         st->pwr_down_mode[chan->channel] = mode + 1;
 170
 171         ret = ad5064_sync_powerdown_mode(st, chan);
 172         mutex_unlock(&indio_dev->mlock);
 173
 174         return ret;
 175 }
 176
 177 static const struct iio_enum ad5064_powerdown_mode_enum = {
 178         .items = ad5064_powerdown_modes,
 179         .num_items = ARRAY_SIZE(ad5064_powerdown_modes),
 180         .get = ad5064_get_powerdown_mode,
 181         .set = ad5064_set_powerdown_mode,
 182 };
 183
 184 static ssize_t ad5064_read_dac_powerdown(struct iio_dev *indio_dev,
 185         uintptr_t private, const struct iio_chan_spec *chan, char *buf)
 186 {
 187         struct ad5064_state *st = iio_priv(indio_dev);
 188
 189         return sprintf(buf, "%d\n", st->pwr_down[chan->channel]);
 190 }
 191
 192 static ssize_t ad5064_write_dac_powerdown(struct iio_dev *indio_dev,
 193          uintptr_t private, const struct iio_chan_spec *chan, const char *buf,
 194          size_t len)
 195 {
 196         struct ad5064_state *st = iio_priv(indio_dev);
 197         bool pwr_down;
 198         int ret;
 199
 200         ret = strtobool(buf, &pwr_down);
 201         if (ret)
 202                 return ret;
 203
 204         mutex_lock(&indio_dev->mlock);
 205         st->pwr_down[chan->channel] = pwr_down;
 206
 207         ret = ad5064_sync_powerdown_mode(st, chan);
 208         mutex_unlock(&indio_dev->mlock);
 209         return ret ? ret : len;
 210 }
 211
 212 static int ad5064_get_vref(struct ad5064_state *st,
 213         struct iio_chan_spec const *chan)
 214 {
 215         unsigned int i;
 216
 217         if (st->use_internal_vref)
 218                 return st->chip_info->internal_vref;
 219
 220         i = st->chip_info->shared_vref ? 0 : chan->channel;
 221         return regulator_get_voltage(st->vref_reg[i].consumer);
 222 }
 223
 224 static int ad5064_read_raw(struct iio_dev *indio_dev,
 225                            struct iio_chan_spec const *chan,
 226                            int *val,
 227                            int *val2,
 228                            long m)
 229 {
 230         struct ad5064_state *st = iio_priv(indio_dev);
 231         int scale_uv;
 232
 233         switch (m) {
 234         case IIO_CHAN_INFO_RAW:
 235                 *val = st->dac_cache[chan->channel];
 236                 return IIO_VAL_INT;
 237         case IIO_CHAN_INFO_SCALE:
 238                 scale_uv = ad5064_get_vref(st, chan);
 239                 if (scale_uv < 0)
 240                         return scale_uv;
 241
 242                 scale_uv = (scale_uv * 100) >> chan->scan_type.realbits;
 243                 *val =  scale_uv / 100000;
 244                 *val2 = (scale_uv % 100000) * 10;
 245                 return IIO_VAL_INT_PLUS_MICRO;
 246         default:
 247                 break;
 248         }
 249         return -EINVAL;
 250 }
 251
 252 static int ad5064_write_raw(struct iio_dev *indio_dev,
 253         struct iio_chan_spec const *chan, int val, int val2, long mask)
 254 {
 255         struct ad5064_state *st = iio_priv(indio_dev);
 256         int ret;
 257
 258         switch (mask) {
 259         case IIO_CHAN_INFO_RAW:
 260                 if (val >= (1 << chan->scan_type.realbits) || val < 0)
 261                         return -EINVAL;
 262
 263                 mutex_lock(&indio_dev->mlock);
 264                 ret = ad5064_write(st, AD5064_CMD_WRITE_INPUT_N_UPDATE_N,
 265                                 chan->address, val, chan->scan_type.shift);
 266                 if (ret == 0)
 267                         st->dac_cache[chan->channel] = val;
 268                 mutex_unlock(&indio_dev->mlock);
 269                 break;
 270         default:
 271                 ret = -EINVAL;
 272         }
 273
 274         return ret;
 275 }
 276
 277 static const struct iio_info ad5064_info = {
 278         .read_raw = ad5064_read_raw,
 279         .write_raw = ad5064_write_raw,
 280         .driver_module = THIS_MODULE,
 281 };
 282
 283 static const struct iio_chan_spec_ext_info ad5064_ext_info[] = {
 284         {
 285                 .name = "powerdown",
 286                 .read = ad5064_read_dac_powerdown,
 287                 .write = ad5064_write_dac_powerdown,
 288         },
 289         IIO_ENUM("powerdown_mode", false, &ad5064_powerdown_mode_enum),
 290         IIO_ENUM_AVAILABLE("powerdown_mode", &ad5064_powerdown_mode_enum),
 291         { },
 292 };
 293
 294 #define AD5064_CHANNEL(chan, addr, bits) {                      \
 295         .type = IIO_VOLTAGE,                                    \
 296         .indexed = 1,                                           \
 297         .output = 1,                                            \
 298         .channel = (chan),                                      \
 299         .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |          \
 300         BIT(IIO_CHAN_INFO_SCALE),                                       \
 301         .address = addr,                                        \
 302         .scan_type = IIO_ST('u', (bits), 16, 20 - (bits)),      \
 303         .ext_info = ad5064_ext_info,                            \
 304 }
 305
 306 #define DECLARE_AD5064_CHANNELS(name, bits) \
 307 const struct iio_chan_spec name[] = { \
 308         AD5064_CHANNEL(0, 0, bits), \
 309         AD5064_CHANNEL(1, 1, bits), \
 310         AD5064_CHANNEL(2, 2, bits), \
 311         AD5064_CHANNEL(3, 3, bits), \
 312         AD5064_CHANNEL(4, 4, bits), \
 313         AD5064_CHANNEL(5, 5, bits), \
 314         AD5064_CHANNEL(6, 6, bits), \
 315         AD5064_CHANNEL(7, 7, bits), \
 316 }
 317
 318 #define DECLARE_AD5065_CHANNELS(name, bits) \
 319 const struct iio_chan_spec name[] = { \
 320         AD5064_CHANNEL(0, 0, bits), \
 321         AD5064_CHANNEL(1, 3, bits), \
 322 }
 323
 324 static DECLARE_AD5064_CHANNELS(ad5024_channels, 12);
 325 static DECLARE_AD5064_CHANNELS(ad5044_channels, 14);
 326 static DECLARE_AD5064_CHANNELS(ad5064_channels, 16);
 327
 328 static DECLARE_AD5065_CHANNELS(ad5025_channels, 12);
 329 static DECLARE_AD5065_CHANNELS(ad5045_channels, 14);
 330 static DECLARE_AD5065_CHANNELS(ad5065_channels, 16);
 331
 332 static const struct ad5064_chip_info ad5064_chip_info_tbl[] = {
 333         [ID_AD5024] = {
 334                 .shared_vref = false,
 335                 .channels = ad5024_channels,
 336                 .num_channels = 4,
 337         },
 338         [ID_AD5025] = {
 339                 .shared_vref = false,
 340                 .channels = ad5025_channels,
 341                 .num_channels = 2,
 342         },
 343         [ID_AD5044] = {
 344                 .shared_vref = false,
 345                 .channels = ad5044_channels,
 346                 .num_channels = 4,
 347         },
 348         [ID_AD5045] = {
 349                 .shared_vref = false,
 350                 .channels = ad5045_channels,
 351                 .num_channels = 2,
 352         },
 353         [ID_AD5064] = {
 354                 .shared_vref = false,
 355                 .channels = ad5064_channels,
 356                 .num_channels = 4,
 357         },
 358         [ID_AD5064_1] = {
 359                 .shared_vref = true,
 360                 .channels = ad5064_channels,
 361                 .num_channels = 4,
 362         },
 363         [ID_AD5065] = {
 364                 .shared_vref = false,
 365                 .channels = ad5065_channels,
 366                 .num_channels = 2,
 367         },
 368         [ID_AD5628_1] = {
 369                 .shared_vref = true,
 370                 .internal_vref = 2500000,
 371                 .channels = ad5024_channels,
 372                 .num_channels = 8,
 373         },
 374         [ID_AD5628_2] = {
 375                 .shared_vref = true,
 376                 .internal_vref = 5000000,
 377                 .channels = ad5024_channels,
 378                 .num_channels = 8,
 379         },
 380         [ID_AD5648_1] = {
 381                 .shared_vref = true,
 382                 .internal_vref = 2500000,
 383                 .channels = ad5044_channels,
 384                 .num_channels = 8,
 385         },
 386         [ID_AD5648_2] = {
 387                 .shared_vref = true,
 388                 .internal_vref = 5000000,
 389                 .channels = ad5044_channels,
 390                 .num_channels = 8,
 391         },
 392         [ID_AD5666_1] = {
 393                 .shared_vref = true,
 394                 .internal_vref = 2500000,
 395                 .channels = ad5064_channels,
 396                 .num_channels = 4,
 397         },
 398         [ID_AD5666_2] = {
 399                 .shared_vref = true,
 400                 .internal_vref = 5000000,
 401                 .channels = ad5064_channels,
 402                 .num_channels = 4,
 403         },
 404         [ID_AD5668_1] = {
 405                 .shared_vref = true,
 406                 .internal_vref = 2500000,
 407                 .channels = ad5064_channels,
 408                 .num_channels = 8,
 409         },
 410         [ID_AD5668_2] = {
 411                 .shared_vref = true,
 412                 .internal_vref = 5000000,
 413                 .channels = ad5064_channels,
 414                 .num_channels = 8,
 415         },
 416 };
 417
 418 static inline unsigned int ad5064_num_vref(struct ad5064_state *st)
 419 {
 420         return st->chip_info->shared_vref ? 1 : st->chip_info->num_channels;
 421 }
 422
 423 static const char * const ad5064_vref_names[] = {
 424         "vrefA",
 425         "vrefB",
 426         "vrefC",
 427         "vrefD",
 428 };
 429
 430 static const char * const ad5064_vref_name(struct ad5064_state *st,
 431         unsigned int vref)
 432 {
 433         return st->chip_info->shared_vref ? "vref" : ad5064_vref_names[vref];
 434 }
 435
 436 static int ad5064_probe(struct device *dev, enum ad5064_type type,
 437                         const char *name, ad5064_write_func write)
 438 {
 439         struct iio_dev *indio_dev;
 440         struct ad5064_state *st;
 441         unsigned int midscale;
 442         unsigned int i;
 443         int ret;
 444
 445         indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
 446         if (indio_dev == NULL)
 447                 return  -ENOMEM;
 448
 449         st = iio_priv(indio_dev);
 450         dev_set_drvdata(dev, indio_dev);
 451
 452         st->chip_info = &ad5064_chip_info_tbl[type];
 453         st->dev = dev;
 454         st->write = write;
 455
 456         for (i = 0; i < ad5064_num_vref(st); ++i)
 457                 st->vref_reg[i].supply = ad5064_vref_name(st, i);
 458
 459         ret = devm_regulator_bulk_get(dev, ad5064_num_vref(st),
 460                 st->vref_reg);
 461         if (ret) {
 462                 if (!st->chip_info->internal_vref)
 463                         return ret;
 464                 st->use_internal_vref = true;
 465                 ret = ad5064_write(st, AD5064_CMD_CONFIG, 0,
 466                         AD5064_CONFIG_INT_VREF_ENABLE, 0);
 467                 if (ret) {
 468                         dev_err(dev, "Failed to enable internal vref: %d\n",
 469                                 ret);
 470                         return ret;
 471                 }
 472         } else {
 473                 ret = regulator_bulk_enable(ad5064_num_vref(st), st->vref_reg);
 474                 if (ret)
 475                         return ret;
 476         }
 477
 478         indio_dev->dev.parent = dev;
 479         indio_dev->name = name;
 480         indio_dev->info = &ad5064_info;
 481         indio_dev->modes = INDIO_DIRECT_MODE;
 482         indio_dev->channels = st->chip_info->channels;
 483         indio_dev->num_channels = st->chip_info->num_channels;
 484
 485         midscale = (1 << indio_dev->channels[0].scan_type.realbits) /  2;
 486
 487         for (i = 0; i < st->chip_info->num_channels; ++i) {
 488                 st->pwr_down_mode[i] = AD5064_LDAC_PWRDN_1K;
 489                 st->dac_cache[i] = midscale;
 490         }
 491
 492         ret = iio_device_register(indio_dev);
 493         if (ret)
 494                 goto error_disable_reg;
 495
 496         return 0;
 497
 498 error_disable_reg:
 499         if (!st->use_internal_vref)
 500                 regulator_bulk_disable(ad5064_num_vref(st), st->vref_reg);
 501
 502         return ret;
 503 }
 504
 505 static int ad5064_remove(struct device *dev)
 506 {
 507         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 508         struct ad5064_state *st = iio_priv(indio_dev);
 509
 510         iio_device_unregister(indio_dev);
 511
 512         if (!st->use_internal_vref)
 513                 regulator_bulk_disable(ad5064_num_vref(st), st->vref_reg);
 514
 515         return 0;
 516 }
 517
 518 #if IS_ENABLED(CONFIG_SPI_MASTER)
 519
 520 static int ad5064_spi_write(struct ad5064_state *st, unsigned int cmd,
 521         unsigned int addr, unsigned int val)
 522 {
 523         struct spi_device *spi = to_spi_device(st->dev);
 524
 525         st->data.spi = cpu_to_be32(AD5064_CMD(cmd) | AD5064_ADDR(addr) | val);
 526         return spi_write(spi, &st->data.spi, sizeof(st->data.spi));
 527 }
 528
 529 static int ad5064_spi_probe(struct spi_device *spi)
 530 {
 531         const struct spi_device_id *id = spi_get_device_id(spi);
 532
 533         return ad5064_probe(&spi->dev, id->driver_data, id->name,
 534                                 ad5064_spi_write);
 535 }
 536
 537 static int ad5064_spi_remove(struct spi_device *spi)
 538 {
 539         return ad5064_remove(&spi->dev);
 540 }
 541
 542 static const struct spi_device_id ad5064_spi_ids[] = {
 543         {"ad5024", ID_AD5024},
 544         {"ad5025", ID_AD5025},
 545         {"ad5044", ID_AD5044},
 546         {"ad5045", ID_AD5045},
 547         {"ad5064", ID_AD5064},
 548         {"ad5064-1", ID_AD5064_1},
 549         {"ad5065", ID_AD5065},
 550         {"ad5628-1", ID_AD5628_1},
 551         {"ad5628-2", ID_AD5628_2},
 552         {"ad5648-1", ID_AD5648_1},
 553         {"ad5648-2", ID_AD5648_2},
 554         {"ad5666-1", ID_AD5666_1},
 555         {"ad5666-2", ID_AD5666_2},
 556         {"ad5668-1", ID_AD5668_1},
 557         {"ad5668-2", ID_AD5668_2},
 558         {"ad5668-3", ID_AD5668_2}, /* similar enough to ad5668-2 */
 559         {}
 560 };
 561 MODULE_DEVICE_TABLE(spi, ad5064_spi_ids);
 562
 563 static struct spi_driver ad5064_spi_driver = {
 564         .driver = {
 565                    .name = "ad5064",
 566                    .owner = THIS_MODULE,
 567         },
 568         .probe = ad5064_spi_probe,
 569         .remove = ad5064_spi_remove,
 570         .id_table = ad5064_spi_ids,
 571 };
 572
 573 static int __init ad5064_spi_register_driver(void)
 574 {
 575         return spi_register_driver(&ad5064_spi_driver);
 576 }
 577
 578 static void ad5064_spi_unregister_driver(void)
 579 {
 580         spi_unregister_driver(&ad5064_spi_driver);
 581 }
 582
 583 #else
 584
 585 static inline int ad5064_spi_register_driver(void) { return 0; }
 586 static inline void ad5064_spi_unregister_driver(void) { }
 587
 588 #endif
 589
 590 #if IS_ENABLED(CONFIG_I2C)
 591
 592 static int ad5064_i2c_write(struct ad5064_state *st, unsigned int cmd,
 593         unsigned int addr, unsigned int val)
 594 {
 595         struct i2c_client *i2c = to_i2c_client(st->dev);
 596
 597         st->data.i2c[0] = (cmd << 4) | addr;
 598         put_unaligned_be16(val, &st->data.i2c[1]);
 599         return i2c_master_send(i2c, st->data.i2c, 3);
 600 }
 601
 602 static int ad5064_i2c_probe(struct i2c_client *i2c,
 603         const struct i2c_device_id *id)
 604 {
 605         return ad5064_probe(&i2c->dev, id->driver_data, id->name,
 606                                                 ad5064_i2c_write);
 607 }
 608
 609 static int ad5064_i2c_remove(struct i2c_client *i2c)
 610 {
 611         return ad5064_remove(&i2c->dev);
 612 }
 613
 614 static const struct i2c_device_id ad5064_i2c_ids[] = {
 615         {"ad5629-1", ID_AD5628_1},
 616         {"ad5629-2", ID_AD5628_2},
 617         {"ad5629-3", ID_AD5628_2}, /* similar enough to ad5629-2 */
 618         {"ad5669-1", ID_AD5668_1},
 619         {"ad5669-2", ID_AD5668_2},
 620         {"ad5669-3", ID_AD5668_2}, /* similar enough to ad5669-2 */
 621         {}
 622 };
 623 MODULE_DEVICE_TABLE(i2c, ad5064_i2c_ids);
 624
 625 static struct i2c_driver ad5064_i2c_driver = {
 626         .driver = {
 627                    .name = "ad5064",
 628                    .owner = THIS_MODULE,
 629         },
 630         .probe = ad5064_i2c_probe,
 631         .remove = ad5064_i2c_remove,
 632         .id_table = ad5064_i2c_ids,
 633 };
 634
 635 static int __init ad5064_i2c_register_driver(void)
 636 {
 637         return i2c_add_driver(&ad5064_i2c_driver);
 638 }
 639
 640 static void __exit ad5064_i2c_unregister_driver(void)
 641 {
 642         i2c_del_driver(&ad5064_i2c_driver);
 643 }
 644
 645 #else
 646
 647 static inline int ad5064_i2c_register_driver(void) { return 0; }
 648 static inline void ad5064_i2c_unregister_driver(void) { }
 649
 650 #endif
 651
 652 static int __init ad5064_init(void)
 653 {
 654         int ret;
 655
 656         ret = ad5064_spi_register_driver();
 657         if (ret)
 658                 return ret;
 659
 660         ret = ad5064_i2c_register_driver();
 661         if (ret) {
 662                 ad5064_spi_unregister_driver();
 663                 return ret;
 664         }
 665
 666         return 0;
 667 }
 668 module_init(ad5064_init);
 669
 670 static void __exit ad5064_exit(void)
 671 {
 672         ad5064_i2c_unregister_driver();
 673         ad5064_spi_unregister_driver();
 674 }
 675 module_exit(ad5064_exit);
 676
 677 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
 678 MODULE_DESCRIPTION("Analog Devices AD5024 and similar multi-channel DACs");
 679 MODULE_LICENSE("GPL v2");