drivers/staging/iio/dac/ad5380.c

   1 /*
   2  * Analog devices AD5380, AD5381, AD5382, AD5383, AD5390, AD5391, AD5392
   3  * multi-channel 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/i2c.h>
  13 #include <linux/kernel.h>
  14 #include <linux/module.h>
  15 #include <linux/spi/spi.h>
  16 #include <linux/slab.h>
  17 #include <linux/sysfs.h>
  18 #include <linux/regmap.h>
  19 #include <linux/regulator/consumer.h>
  20
  21 #include "../iio.h"
  22 #include "../sysfs.h"
  23 #include "dac.h"
  24
  25
  26 #define AD5380_REG_DATA(x)      (((x) << 2) | 3)
  27 #define AD5380_REG_OFFSET(x)    (((x) << 2) | 2)
  28 #define AD5380_REG_GAIN(x)      (((x) << 2) | 1)
  29 #define AD5380_REG_SF_PWR_DOWN  (8 << 2)
  30 #define AD5380_REG_SF_PWR_UP    (9 << 2)
  31 #define AD5380_REG_SF_CTRL      (12 << 2)
  32
  33 #define AD5380_CTRL_PWR_DOWN_MODE_OFFSET        13
  34 #define AD5380_CTRL_INT_VREF_2V5                BIT(12)
  35 #define AD5380_CTRL_INT_VREF_EN                 BIT(10)
  36
  37 /**
  38  * struct ad5380_chip_info - chip specific information
  39  * @channel_template:   channel specification template
  40  * @num_channels:       number of channels
  41  * @int_vref:           internal vref in uV
  42 */
  43
  44 struct ad5380_chip_info {
  45         struct iio_chan_spec    channel_template;
  46         unsigned int            num_channels;
  47         unsigned int            int_vref;
  48 };
  49
  50 /**
  51  * struct ad5380_state - driver instance specific data
  52  * @regmap:             regmap instance used by the device
  53  * @chip_info:          chip model specific constants, available modes etc
  54  * @vref_reg:           vref supply regulator
  55  * @vref:               actual reference voltage used in uA
  56  * @pwr_down:           whether the chip is currently in power down mode
  57  */
  58
  59 struct ad5380_state {
  60         struct regmap                   *regmap;
  61         const struct ad5380_chip_info   *chip_info;
  62         struct regulator                *vref_reg;
  63         int                             vref;
  64         bool                            pwr_down;
  65 };
  66
  67 enum ad5380_type {
  68         ID_AD5380_3,
  69         ID_AD5380_5,
  70         ID_AD5381_3,
  71         ID_AD5381_5,
  72         ID_AD5382_3,
  73         ID_AD5382_5,
  74         ID_AD5383_3,
  75         ID_AD5383_5,
  76         ID_AD5390_3,
  77         ID_AD5390_5,
  78         ID_AD5391_3,
  79         ID_AD5391_5,
  80         ID_AD5392_3,
  81         ID_AD5392_5,
  82 };
  83
  84 #define AD5380_CHANNEL(_bits) {                                 \
  85         .type = IIO_VOLTAGE,                                    \
  86         .indexed = 1,                                           \
  87         .output = 1,                                            \
  88         .info_mask = IIO_CHAN_INFO_SCALE_SHARED_BIT |           \
  89                 IIO_CHAN_INFO_CALIBSCALE_SEPARATE_BIT |         \
  90                 IIO_CHAN_INFO_CALIBBIAS_SEPARATE_BIT,           \
  91         .scan_type = IIO_ST('u', (_bits), 16, 14 - (_bits))     \
  92 }
  93
  94 static const struct ad5380_chip_info ad5380_chip_info_tbl[] = {
  95         [ID_AD5380_3] = {
  96                 .channel_template = AD5380_CHANNEL(14),
  97                 .num_channels = 40,
  98                 .int_vref = 1250000,
  99         },
 100         [ID_AD5380_5] = {
 101                 .channel_template = AD5380_CHANNEL(14),
 102                 .num_channels = 40,
 103                 .int_vref = 2500000,
 104         },
 105         [ID_AD5381_3] = {
 106                 .channel_template = AD5380_CHANNEL(12),
 107                 .num_channels = 16,
 108                 .int_vref = 1250000,
 109         },
 110         [ID_AD5381_5] = {
 111                 .channel_template = AD5380_CHANNEL(12),
 112                 .num_channels = 16,
 113                 .int_vref = 2500000,
 114         },
 115         [ID_AD5382_3] = {
 116                 .channel_template = AD5380_CHANNEL(14),
 117                 .num_channels = 32,
 118                 .int_vref = 1250000,
 119         },
 120         [ID_AD5382_5] = {
 121                 .channel_template = AD5380_CHANNEL(14),
 122                 .num_channels = 32,
 123                 .int_vref = 2500000,
 124         },
 125         [ID_AD5383_3] = {
 126                 .channel_template = AD5380_CHANNEL(12),
 127                 .num_channels = 32,
 128                 .int_vref = 1250000,
 129         },
 130         [ID_AD5383_5] = {
 131                 .channel_template = AD5380_CHANNEL(12),
 132                 .num_channels = 32,
 133                 .int_vref = 2500000,
 134         },
 135         [ID_AD5390_3] = {
 136                 .channel_template = AD5380_CHANNEL(14),
 137                 .num_channels = 16,
 138                 .int_vref = 1250000,
 139         },
 140         [ID_AD5390_5] = {
 141                 .channel_template = AD5380_CHANNEL(14),
 142                 .num_channels = 16,
 143                 .int_vref = 2500000,
 144         },
 145         [ID_AD5391_3] = {
 146                 .channel_template = AD5380_CHANNEL(12),
 147                 .num_channels = 16,
 148                 .int_vref = 1250000,
 149         },
 150         [ID_AD5391_5] = {
 151                 .channel_template = AD5380_CHANNEL(12),
 152                 .num_channels = 16,
 153                 .int_vref = 2500000,
 154         },
 155         [ID_AD5392_3] = {
 156                 .channel_template = AD5380_CHANNEL(14),
 157                 .num_channels = 8,
 158                 .int_vref = 1250000,
 159         },
 160         [ID_AD5392_5] = {
 161                 .channel_template = AD5380_CHANNEL(14),
 162                 .num_channels = 8,
 163                 .int_vref = 2500000,
 164         },
 165 };
 166
 167 static ssize_t ad5380_read_dac_powerdown(struct device *dev,
 168         struct device_attribute *attr, char *buf)
 169 {
 170         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 171         struct ad5380_state *st = iio_priv(indio_dev);
 172
 173         return sprintf(buf, "%d\n", st->pwr_down);
 174 }
 175
 176 static ssize_t ad5380_write_dac_powerdown(struct device *dev,
 177         struct device_attribute *attr, const char *buf, size_t len)
 178 {
 179         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 180         struct ad5380_state *st = iio_priv(indio_dev);
 181         bool pwr_down;
 182         int ret;
 183
 184         ret = strtobool(buf, &pwr_down);
 185         if (ret)
 186                 return ret;
 187
 188         mutex_lock(&indio_dev->mlock);
 189
 190         if (pwr_down)
 191                 ret = regmap_write(st->regmap, AD5380_REG_SF_PWR_DOWN, 0);
 192         else
 193                 ret = regmap_write(st->regmap, AD5380_REG_SF_PWR_UP, 0);
 194
 195         st->pwr_down = pwr_down;
 196
 197         mutex_unlock(&indio_dev->mlock);
 198
 199         return ret ? ret : len;
 200 }
 201
 202 static IIO_DEVICE_ATTR(out_voltage_powerdown,
 203                         S_IRUGO | S_IWUSR,
 204                         ad5380_read_dac_powerdown,
 205                         ad5380_write_dac_powerdown, 0);
 206
 207 static const char ad5380_powerdown_modes[][15] = {
 208         [0]     = "100kohm_to_gnd",
 209         [1]     = "three_state",
 210 };
 211
 212 static ssize_t ad5380_read_powerdown_mode(struct device *dev,
 213         struct device_attribute *attr, char *buf)
 214 {
 215         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 216         struct ad5380_state *st = iio_priv(indio_dev);
 217         unsigned int mode;
 218         int ret;
 219
 220         ret = regmap_read(st->regmap, AD5380_REG_SF_CTRL, &mode);
 221         if (ret)
 222                 return ret;
 223
 224         mode = (mode >> AD5380_CTRL_PWR_DOWN_MODE_OFFSET) & 1;
 225
 226         return sprintf(buf, "%s\n", ad5380_powerdown_modes[mode]);
 227 }
 228
 229 static ssize_t ad5380_write_powerdown_mode(struct device *dev,
 230         struct device_attribute *attr, const char *buf, size_t len)
 231 {
 232         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 233         struct ad5380_state *st = iio_priv(indio_dev);
 234         unsigned int i;
 235         int ret;
 236
 237         for (i = 0; i < ARRAY_SIZE(ad5380_powerdown_modes); ++i) {
 238                 if (sysfs_streq(buf, ad5380_powerdown_modes[i]))
 239                         break;
 240         }
 241
 242         if (i == ARRAY_SIZE(ad5380_powerdown_modes))
 243                 return -EINVAL;
 244
 245         ret = regmap_update_bits(st->regmap, AD5380_REG_SF_CTRL,
 246                 1 << AD5380_CTRL_PWR_DOWN_MODE_OFFSET,
 247                 i << AD5380_CTRL_PWR_DOWN_MODE_OFFSET);
 248
 249         return ret ? ret : len;
 250 }
 251
 252 static IIO_DEVICE_ATTR(out_voltage_powerdown_mode,
 253                         S_IRUGO | S_IWUSR,
 254                         ad5380_read_powerdown_mode,
 255                         ad5380_write_powerdown_mode, 0);
 256
 257 static IIO_CONST_ATTR(out_voltage_powerdown_mode_available,
 258                         "100kohm_to_gnd three_state");
 259
 260 static struct attribute *ad5380_attributes[] = {
 261         &iio_dev_attr_out_voltage_powerdown.dev_attr.attr,
 262         &iio_dev_attr_out_voltage_powerdown_mode.dev_attr.attr,
 263         &iio_const_attr_out_voltage_powerdown_mode_available.dev_attr.attr,
 264         NULL,
 265 };
 266
 267 static const struct attribute_group ad5380_attribute_group = {
 268         .attrs = ad5380_attributes,
 269 };
 270
 271 static unsigned int ad5380_info_to_reg(struct iio_chan_spec const *chan,
 272         long info)
 273 {
 274         switch (info) {
 275         case 0:
 276                 return AD5380_REG_DATA(chan->address);
 277         case IIO_CHAN_INFO_CALIBBIAS:
 278                 return AD5380_REG_OFFSET(chan->address);
 279         case IIO_CHAN_INFO_CALIBSCALE:
 280                 return AD5380_REG_GAIN(chan->address);
 281         default:
 282                 break;
 283         }
 284
 285         return 0;
 286 }
 287
 288 static int ad5380_write_raw(struct iio_dev *indio_dev,
 289         struct iio_chan_spec const *chan, int val, int val2, long info)
 290 {
 291         const unsigned int max_val = (1 << chan->scan_type.realbits);
 292         struct ad5380_state *st = iio_priv(indio_dev);
 293
 294         switch (info) {
 295         case 0:
 296         case IIO_CHAN_INFO_CALIBSCALE:
 297                 if (val >= max_val || val < 0)
 298                         return -EINVAL;
 299
 300                 return regmap_write(st->regmap,
 301                         ad5380_info_to_reg(chan, info),
 302                         val << chan->scan_type.shift);
 303         case IIO_CHAN_INFO_CALIBBIAS:
 304                 val += (1 << chan->scan_type.realbits) / 2;
 305                 if (val >= max_val || val < 0)
 306                         return -EINVAL;
 307
 308                 return regmap_write(st->regmap,
 309                         AD5380_REG_OFFSET(chan->address),
 310                         val << chan->scan_type.shift);
 311         default:
 312                 break;
 313         }
 314         return -EINVAL;
 315 }
 316
 317 static int ad5380_read_raw(struct iio_dev *indio_dev,
 318         struct iio_chan_spec const *chan, int *val, int *val2, long info)
 319 {
 320         struct ad5380_state *st = iio_priv(indio_dev);
 321         unsigned long scale_uv;
 322         int ret;
 323
 324         switch (info) {
 325         case 0:
 326         case IIO_CHAN_INFO_CALIBSCALE:
 327                 ret = regmap_read(st->regmap, ad5380_info_to_reg(chan, info),
 328                                         val);
 329                 if (ret)
 330                         return ret;
 331                 *val >>= chan->scan_type.shift;
 332                 return IIO_VAL_INT;
 333         case IIO_CHAN_INFO_CALIBBIAS:
 334                 ret = regmap_read(st->regmap, AD5380_REG_OFFSET(chan->address),
 335                                         val);
 336                 if (ret)
 337                         return ret;
 338                 *val >>= chan->scan_type.shift;
 339                 val -= (1 << chan->scan_type.realbits) / 2;
 340                 return IIO_VAL_INT;
 341         case IIO_CHAN_INFO_SCALE:
 342                 scale_uv = ((2 * st->vref) >> chan->scan_type.realbits) * 100;
 343                 *val =  scale_uv / 100000;
 344                 *val2 = (scale_uv % 100000) * 10;
 345                 return IIO_VAL_INT_PLUS_MICRO;
 346         default:
 347                 break;
 348         }
 349
 350         return -EINVAL;
 351 }
 352
 353 static const struct iio_info ad5380_info = {
 354         .read_raw = ad5380_read_raw,
 355         .write_raw = ad5380_write_raw,
 356         .attrs = &ad5380_attribute_group,
 357         .driver_module = THIS_MODULE,
 358 };
 359
 360 static int __devinit ad5380_alloc_channels(struct iio_dev *indio_dev)
 361 {
 362         struct ad5380_state *st = iio_priv(indio_dev);
 363         struct iio_chan_spec *channels;
 364         unsigned int i;
 365
 366         channels = kcalloc(sizeof(struct iio_chan_spec),
 367                         st->chip_info->num_channels, GFP_KERNEL);
 368
 369         if (!channels)
 370                 return -ENOMEM;
 371
 372         for (i = 0; i < st->chip_info->num_channels; ++i) {
 373                 channels[i] = st->chip_info->channel_template;
 374                 channels[i].channel = i;
 375                 channels[i].address = i;
 376         }
 377
 378         indio_dev->channels = channels;
 379
 380         return 0;
 381 }
 382
 383 static int __devinit ad5380_probe(struct device *dev, struct regmap *regmap,
 384         enum ad5380_type type, const char *name)
 385 {
 386         struct iio_dev *indio_dev;
 387         struct ad5380_state *st;
 388         unsigned int ctrl = 0;
 389         int ret;
 390
 391         indio_dev = iio_allocate_device(sizeof(*st));
 392         if (indio_dev == NULL) {
 393                 dev_err(dev, "Failed to allocate iio device\n");
 394                 ret = -ENOMEM;
 395                 goto error_regmap_exit;
 396         }
 397
 398         st = iio_priv(indio_dev);
 399         dev_set_drvdata(dev, indio_dev);
 400
 401         st->chip_info = &ad5380_chip_info_tbl[type];
 402         st->regmap = regmap;
 403
 404         indio_dev->dev.parent = dev;
 405         indio_dev->name = name;
 406         indio_dev->info = &ad5380_info;
 407         indio_dev->modes = INDIO_DIRECT_MODE;
 408         indio_dev->num_channels = st->chip_info->num_channels;
 409
 410         ret = ad5380_alloc_channels(indio_dev);
 411         if (ret) {
 412                 dev_err(dev, "Failed to allocate channel spec: %d\n", ret);
 413                 goto error_free;
 414         }
 415
 416         if (st->chip_info->int_vref == 2500000)
 417                 ctrl |= AD5380_CTRL_INT_VREF_2V5;
 418
 419         st->vref_reg = regulator_get(dev, "vref");
 420         if (!IS_ERR(st->vref_reg)) {
 421                 ret = regulator_enable(st->vref_reg);
 422                 if (ret) {
 423                         dev_err(dev, "Failed to enable vref regulators: %d\n",
 424                                 ret);
 425                         goto error_free_reg;
 426                 }
 427
 428                 st->vref = regulator_get_voltage(st->vref_reg);
 429         } else {
 430                 st->vref = st->chip_info->int_vref;
 431                 ctrl |= AD5380_CTRL_INT_VREF_EN;
 432         }
 433
 434         ret = regmap_write(st->regmap, AD5380_REG_SF_CTRL, ctrl);
 435         if (ret) {
 436                 dev_err(dev, "Failed to write to device: %d\n", ret);
 437                 goto error_disable_reg;
 438         }
 439
 440         ret = iio_device_register(indio_dev);
 441         if (ret) {
 442                 dev_err(dev, "Failed to register iio device: %d\n", ret);
 443                 goto error_disable_reg;
 444         }
 445
 446         return 0;
 447
 448 error_disable_reg:
 449         if (!IS_ERR(st->vref_reg))
 450                 regulator_disable(st->vref_reg);
 451 error_free_reg:
 452         if (!IS_ERR(st->vref_reg))
 453                 regulator_put(st->vref_reg);
 454
 455         kfree(indio_dev->channels);
 456 error_free:
 457         iio_free_device(indio_dev);
 458 error_regmap_exit:
 459         regmap_exit(regmap);
 460
 461         return ret;
 462 }
 463
 464 static int __devexit ad5380_remove(struct device *dev)
 465 {
 466         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 467         struct ad5380_state *st = iio_priv(indio_dev);
 468
 469         iio_device_unregister(indio_dev);
 470
 471         kfree(indio_dev->channels);
 472
 473         if (!IS_ERR(st->vref_reg)) {
 474                 regulator_disable(st->vref_reg);
 475                 regulator_put(st->vref_reg);
 476         }
 477
 478         regmap_exit(st->regmap);
 479         iio_free_device(indio_dev);
 480
 481         return 0;
 482 }
 483
 484 static bool ad5380_reg_false(struct device *dev, unsigned int reg)
 485 {
 486         return false;
 487 }
 488
 489 static const struct regmap_config ad5380_regmap_config = {
 490         .reg_bits = 10,
 491         .val_bits = 14,
 492
 493         .max_register = AD5380_REG_DATA(40),
 494         .cache_type = REGCACHE_RBTREE,
 495
 496         .volatile_reg = ad5380_reg_false,
 497         .readable_reg = ad5380_reg_false,
 498 };
 499
 500 #if IS_ENABLED(CONFIG_SPI_MASTER)
 501
 502 static int __devinit ad5380_spi_probe(struct spi_device *spi)
 503 {
 504         const struct spi_device_id *id = spi_get_device_id(spi);
 505         struct regmap *regmap;
 506
 507         regmap = regmap_init_spi(spi, &ad5380_regmap_config);
 508
 509         if (IS_ERR(regmap))
 510                 return PTR_ERR(regmap);
 511
 512         return ad5380_probe(&spi->dev, regmap, id->driver_data, id->name);
 513 }
 514
 515 static int __devexit ad5380_spi_remove(struct spi_device *spi)
 516 {
 517         return ad5380_remove(&spi->dev);
 518 }
 519
 520 static const struct spi_device_id ad5380_spi_ids[] = {
 521         { "ad5380-3", ID_AD5380_3 },
 522         { "ad5380-5", ID_AD5380_5 },
 523         { "ad5381-3", ID_AD5381_3 },
 524         { "ad5381-5", ID_AD5381_5 },
 525         { "ad5382-3", ID_AD5382_3 },
 526         { "ad5382-5", ID_AD5382_5 },
 527         { "ad5383-3", ID_AD5383_3 },
 528         { "ad5383-5", ID_AD5383_5 },
 529         { "ad5384-3", ID_AD5380_3 },
 530         { "ad5384-5", ID_AD5380_5 },
 531         { "ad5390-3", ID_AD5390_3 },
 532         { "ad5390-5", ID_AD5390_5 },
 533         { "ad5391-3", ID_AD5391_3 },
 534         { "ad5391-5", ID_AD5391_5 },
 535         { "ad5392-3", ID_AD5392_3 },
 536         { "ad5392-5", ID_AD5392_5 },
 537         { }
 538 };
 539 MODULE_DEVICE_TABLE(spi, ad5380_spi_ids);
 540
 541 static struct spi_driver ad5380_spi_driver = {
 542         .driver = {
 543                    .name = "ad5380",
 544                    .owner = THIS_MODULE,
 545         },
 546         .probe = ad5380_spi_probe,
 547         .remove = __devexit_p(ad5380_spi_remove),
 548         .id_table = ad5380_spi_ids,
 549 };
 550
 551 static inline int ad5380_spi_register_driver(void)
 552 {
 553         return spi_register_driver(&ad5380_spi_driver);
 554 }
 555
 556 static inline void ad5380_spi_unregister_driver(void)
 557 {
 558         spi_unregister_driver(&ad5380_spi_driver);
 559 }
 560
 561 #else
 562
 563 static inline int ad5380_spi_register_driver(void)
 564 {
 565         return 0;
 566 }
 567
 568 static inline void ad5380_spi_unregister_driver(void)
 569 {
 570 }
 571
 572 #endif
 573
 574 #if IS_ENABLED(CONFIG_I2C)
 575
 576 static int __devinit ad5380_i2c_probe(struct i2c_client *i2c,
 577         const struct i2c_device_id *id)
 578 {
 579         struct regmap *regmap;
 580
 581         regmap = regmap_init_i2c(i2c, &ad5380_regmap_config);
 582
 583         if (IS_ERR(regmap))
 584                 return PTR_ERR(regmap);
 585
 586         return ad5380_probe(&i2c->dev, regmap, id->driver_data, id->name);
 587 }
 588
 589 static int __devexit ad5380_i2c_remove(struct i2c_client *i2c)
 590 {
 591         return ad5380_remove(&i2c->dev);
 592 }
 593
 594 static const struct i2c_device_id ad5380_i2c_ids[] = {
 595         { "ad5380-3", ID_AD5380_3 },
 596         { "ad5380-5", ID_AD5380_5 },
 597         { "ad5381-3", ID_AD5381_3 },
 598         { "ad5381-5", ID_AD5381_5 },
 599         { "ad5382-3", ID_AD5382_3 },
 600         { "ad5382-5", ID_AD5382_5 },
 601         { "ad5383-3", ID_AD5383_3 },
 602         { "ad5383-5", ID_AD5383_5 },
 603         { "ad5384-3", ID_AD5380_3 },
 604         { "ad5384-5", ID_AD5380_5 },
 605         { "ad5390-3", ID_AD5390_3 },
 606         { "ad5390-5", ID_AD5390_5 },
 607         { "ad5391-3", ID_AD5391_3 },
 608         { "ad5391-5", ID_AD5391_5 },
 609         { "ad5392-3", ID_AD5392_3 },
 610         { "ad5392-5", ID_AD5392_5 },
 611         { }
 612 };
 613 MODULE_DEVICE_TABLE(i2c, ad5380_i2c_ids);
 614
 615 static struct i2c_driver ad5380_i2c_driver = {
 616         .driver = {
 617                    .name = "ad5380",
 618                    .owner = THIS_MODULE,
 619         },
 620         .probe = ad5380_i2c_probe,
 621         .remove = __devexit_p(ad5380_i2c_remove),
 622         .id_table = ad5380_i2c_ids,
 623 };
 624
 625 static inline int ad5380_i2c_register_driver(void)
 626 {
 627         return i2c_add_driver(&ad5380_i2c_driver);
 628 }
 629
 630 static inline void ad5380_i2c_unregister_driver(void)
 631 {
 632         i2c_del_driver(&ad5380_i2c_driver);
 633 }
 634
 635 #else
 636
 637 static inline int ad5380_i2c_register_driver(void)
 638 {
 639         return 0;
 640 }
 641
 642 static inline void ad5380_i2c_unregister_driver(void)
 643 {
 644 }
 645
 646 #endif
 647
 648 static int __init ad5380_spi_init(void)
 649 {
 650         int ret;
 651
 652         ret = ad5380_spi_register_driver();
 653         if (ret)
 654                 return ret;
 655
 656         ret = ad5380_i2c_register_driver();
 657         if (ret) {
 658                 ad5380_spi_unregister_driver();
 659                 return ret;
 660         }
 661
 662         return 0;
 663 }
 664 module_init(ad5380_spi_init);
 665
 666 static void __exit ad5380_spi_exit(void)
 667 {
 668         ad5380_i2c_unregister_driver();
 669         ad5380_spi_unregister_driver();
 670
 671 }
 672 module_exit(ad5380_spi_exit);
 673
 674 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
 675 MODULE_DESCRIPTION("Analog Devices AD5380/81/82/83/84/90/91/92 DAC");
 676 MODULE_LICENSE("GPL v2");