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_AD5629_1, 117 ID_AD5629_2, 118 ID_AD5648_1, 119 ID_AD5648_2, 120 ID_AD5666_1, 121 ID_AD5666_2, 122 ID_AD5668_1, 123 ID_AD5668_2, 124 ID_AD5669_1, 125 ID_AD5669_2, 126 }; 127 128 static int ad5064_write(struct ad5064_state *st, unsigned int cmd, 129 unsigned int addr, unsigned int val, unsigned int shift) 130 { 131 val <<= shift; 132 133 return st->write(st, cmd, addr, val); 134 } 135 136 static int ad5064_sync_powerdown_mode(struct ad5064_state *st, 137 const struct iio_chan_spec *chan) 138 { 139 unsigned int val; 140 int ret; 141 142 val = (0x1 << chan->address); 143 144 if (st->pwr_down[chan->channel]) 145 val |= st->pwr_down_mode[chan->channel] << 8; 146 147 ret = ad5064_write(st, AD5064_CMD_POWERDOWN_DAC, 0, val, 0); 148 149 return ret; 150 } 151 152 static const char * const ad5064_powerdown_modes[] = { 153 "1kohm_to_gnd", 154 "100kohm_to_gnd", 155 "three_state", 156 }; 157 158 static int ad5064_get_powerdown_mode(struct iio_dev *indio_dev, 159 const struct iio_chan_spec *chan) 160 { 161 struct ad5064_state *st = iio_priv(indio_dev); 162 163 return st->pwr_down_mode[chan->channel] - 1; 164 } 165 166 static int ad5064_set_powerdown_mode(struct iio_dev *indio_dev, 167 const struct iio_chan_spec *chan, unsigned int mode) 168 { 169 struct ad5064_state *st = iio_priv(indio_dev); 170 int ret; 171 172 mutex_lock(&indio_dev->mlock); 173 st->pwr_down_mode[chan->channel] = mode + 1; 174 175 ret = ad5064_sync_powerdown_mode(st, chan); 176 mutex_unlock(&indio_dev->mlock); 177 178 return ret; 179 } 180 181 static const struct iio_enum ad5064_powerdown_mode_enum = { 182 .items = ad5064_powerdown_modes, 183 .num_items = ARRAY_SIZE(ad5064_powerdown_modes), 184 .get = ad5064_get_powerdown_mode, 185 .set = ad5064_set_powerdown_mode, 186 }; 187 188 static ssize_t ad5064_read_dac_powerdown(struct iio_dev *indio_dev, 189 uintptr_t private, const struct iio_chan_spec *chan, char *buf) 190 { 191 struct ad5064_state *st = iio_priv(indio_dev); 192 193 return sprintf(buf, "%d\n", st->pwr_down[chan->channel]); 194 } 195 196 static ssize_t ad5064_write_dac_powerdown(struct iio_dev *indio_dev, 197 uintptr_t private, const struct iio_chan_spec *chan, const char *buf, 198 size_t len) 199 { 200 struct ad5064_state *st = iio_priv(indio_dev); 201 bool pwr_down; 202 int ret; 203 204 ret = strtobool(buf, &pwr_down); 205 if (ret) 206 return ret; 207 208 mutex_lock(&indio_dev->mlock); 209 st->pwr_down[chan->channel] = pwr_down; 210 211 ret = ad5064_sync_powerdown_mode(st, chan); 212 mutex_unlock(&indio_dev->mlock); 213 return ret ? ret : len; 214 } 215 216 static int ad5064_get_vref(struct ad5064_state *st, 217 struct iio_chan_spec const *chan) 218 { 219 unsigned int i; 220 221 if (st->use_internal_vref) 222 return st->chip_info->internal_vref; 223 224 i = st->chip_info->shared_vref ? 0 : chan->channel; 225 return regulator_get_voltage(st->vref_reg[i].consumer); 226 } 227 228 static int ad5064_read_raw(struct iio_dev *indio_dev, 229 struct iio_chan_spec const *chan, 230 int *val, 231 int *val2, 232 long m) 233 { 234 struct ad5064_state *st = iio_priv(indio_dev); 235 int scale_uv; 236 237 switch (m) { 238 case IIO_CHAN_INFO_RAW: 239 *val = st->dac_cache[chan->channel]; 240 return IIO_VAL_INT; 241 case IIO_CHAN_INFO_SCALE: 242 scale_uv = ad5064_get_vref(st, chan); 243 if (scale_uv < 0) 244 return scale_uv; 245 246 *val = scale_uv / 1000; 247 *val2 = chan->scan_type.realbits; 248 return IIO_VAL_FRACTIONAL_LOG2; 249 default: 250 break; 251 } 252 return -EINVAL; 253 } 254 255 static int ad5064_write_raw(struct iio_dev *indio_dev, 256 struct iio_chan_spec const *chan, int val, int val2, long mask) 257 { 258 struct ad5064_state *st = iio_priv(indio_dev); 259 int ret; 260 261 switch (mask) { 262 case IIO_CHAN_INFO_RAW: 263 if (val >= (1 << chan->scan_type.realbits) || val < 0) 264 return -EINVAL; 265 266 mutex_lock(&indio_dev->mlock); 267 ret = ad5064_write(st, AD5064_CMD_WRITE_INPUT_N_UPDATE_N, 268 chan->address, val, chan->scan_type.shift); 269 if (ret == 0) 270 st->dac_cache[chan->channel] = val; 271 mutex_unlock(&indio_dev->mlock); 272 break; 273 default: 274 ret = -EINVAL; 275 } 276 277 return ret; 278 } 279 280 static const struct iio_info ad5064_info = { 281 .read_raw = ad5064_read_raw, 282 .write_raw = ad5064_write_raw, 283 .driver_module = THIS_MODULE, 284 }; 285 286 static const struct iio_chan_spec_ext_info ad5064_ext_info[] = { 287 { 288 .name = "powerdown", 289 .read = ad5064_read_dac_powerdown, 290 .write = ad5064_write_dac_powerdown, 291 .shared = IIO_SEPARATE, 292 }, 293 IIO_ENUM("powerdown_mode", IIO_SEPARATE, &ad5064_powerdown_mode_enum), 294 IIO_ENUM_AVAILABLE("powerdown_mode", &ad5064_powerdown_mode_enum), 295 { }, 296 }; 297 298 #define AD5064_CHANNEL(chan, addr, bits, _shift) { \ 299 .type = IIO_VOLTAGE, \ 300 .indexed = 1, \ 301 .output = 1, \ 302 .channel = (chan), \ 303 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \ 304 BIT(IIO_CHAN_INFO_SCALE), \ 305 .address = addr, \ 306 .scan_type = { \ 307 .sign = 'u', \ 308 .realbits = (bits), \ 309 .storagebits = 16, \ 310 .shift = (_shift), \ 311 }, \ 312 .ext_info = ad5064_ext_info, \ 313 } 314 315 #define DECLARE_AD5064_CHANNELS(name, bits, shift) \ 316 const struct iio_chan_spec name[] = { \ 317 AD5064_CHANNEL(0, 0, bits, shift), \ 318 AD5064_CHANNEL(1, 1, bits, shift), \ 319 AD5064_CHANNEL(2, 2, bits, shift), \ 320 AD5064_CHANNEL(3, 3, bits, shift), \ 321 AD5064_CHANNEL(4, 4, bits, shift), \ 322 AD5064_CHANNEL(5, 5, bits, shift), \ 323 AD5064_CHANNEL(6, 6, bits, shift), \ 324 AD5064_CHANNEL(7, 7, bits, shift), \ 325 } 326 327 #define DECLARE_AD5065_CHANNELS(name, bits, shift) \ 328 const struct iio_chan_spec name[] = { \ 329 AD5064_CHANNEL(0, 0, bits, shift), \ 330 AD5064_CHANNEL(1, 3, bits, shift), \ 331 } 332 333 static DECLARE_AD5064_CHANNELS(ad5024_channels, 12, 8); 334 static DECLARE_AD5064_CHANNELS(ad5044_channels, 14, 6); 335 static DECLARE_AD5064_CHANNELS(ad5064_channels, 16, 4); 336 337 static DECLARE_AD5065_CHANNELS(ad5025_channels, 12, 8); 338 static DECLARE_AD5065_CHANNELS(ad5045_channels, 14, 6); 339 static DECLARE_AD5065_CHANNELS(ad5065_channels, 16, 4); 340 341 static DECLARE_AD5064_CHANNELS(ad5629_channels, 12, 4); 342 static DECLARE_AD5064_CHANNELS(ad5669_channels, 16, 0); 343 344 static const struct ad5064_chip_info ad5064_chip_info_tbl[] = { 345 [ID_AD5024] = { 346 .shared_vref = false, 347 .channels = ad5024_channels, 348 .num_channels = 4, 349 }, 350 [ID_AD5025] = { 351 .shared_vref = false, 352 .channels = ad5025_channels, 353 .num_channels = 2, 354 }, 355 [ID_AD5044] = { 356 .shared_vref = false, 357 .channels = ad5044_channels, 358 .num_channels = 4, 359 }, 360 [ID_AD5045] = { 361 .shared_vref = false, 362 .channels = ad5045_channels, 363 .num_channels = 2, 364 }, 365 [ID_AD5064] = { 366 .shared_vref = false, 367 .channels = ad5064_channels, 368 .num_channels = 4, 369 }, 370 [ID_AD5064_1] = { 371 .shared_vref = true, 372 .channels = ad5064_channels, 373 .num_channels = 4, 374 }, 375 [ID_AD5065] = { 376 .shared_vref = false, 377 .channels = ad5065_channels, 378 .num_channels = 2, 379 }, 380 [ID_AD5628_1] = { 381 .shared_vref = true, 382 .internal_vref = 2500000, 383 .channels = ad5024_channels, 384 .num_channels = 8, 385 }, 386 [ID_AD5628_2] = { 387 .shared_vref = true, 388 .internal_vref = 5000000, 389 .channels = ad5024_channels, 390 .num_channels = 8, 391 }, 392 [ID_AD5629_1] = { 393 .shared_vref = true, 394 .internal_vref = 2500000, 395 .channels = ad5629_channels, 396 .num_channels = 8, 397 }, 398 [ID_AD5629_2] = { 399 .shared_vref = true, 400 .internal_vref = 5000000, 401 .channels = ad5629_channels, 402 .num_channels = 8, 403 }, 404 [ID_AD5648_1] = { 405 .shared_vref = true, 406 .internal_vref = 2500000, 407 .channels = ad5044_channels, 408 .num_channels = 8, 409 }, 410 [ID_AD5648_2] = { 411 .shared_vref = true, 412 .internal_vref = 5000000, 413 .channels = ad5044_channels, 414 .num_channels = 8, 415 }, 416 [ID_AD5666_1] = { 417 .shared_vref = true, 418 .internal_vref = 2500000, 419 .channels = ad5064_channels, 420 .num_channels = 4, 421 }, 422 [ID_AD5666_2] = { 423 .shared_vref = true, 424 .internal_vref = 5000000, 425 .channels = ad5064_channels, 426 .num_channels = 4, 427 }, 428 [ID_AD5668_1] = { 429 .shared_vref = true, 430 .internal_vref = 2500000, 431 .channels = ad5064_channels, 432 .num_channels = 8, 433 }, 434 [ID_AD5668_2] = { 435 .shared_vref = true, 436 .internal_vref = 5000000, 437 .channels = ad5064_channels, 438 .num_channels = 8, 439 }, 440 [ID_AD5669_1] = { 441 .shared_vref = true, 442 .internal_vref = 2500000, 443 .channels = ad5669_channels, 444 .num_channels = 8, 445 }, 446 [ID_AD5669_2] = { 447 .shared_vref = true, 448 .internal_vref = 5000000, 449 .channels = ad5669_channels, 450 .num_channels = 8, 451 }, 452 }; 453 454 static inline unsigned int ad5064_num_vref(struct ad5064_state *st) 455 { 456 return st->chip_info->shared_vref ? 1 : st->chip_info->num_channels; 457 } 458 459 static const char * const ad5064_vref_names[] = { 460 "vrefA", 461 "vrefB", 462 "vrefC", 463 "vrefD", 464 }; 465 466 static const char * const ad5064_vref_name(struct ad5064_state *st, 467 unsigned int vref) 468 { 469 return st->chip_info->shared_vref ? "vref" : ad5064_vref_names[vref]; 470 } 471 472 static int ad5064_probe(struct device *dev, enum ad5064_type type, 473 const char *name, ad5064_write_func write) 474 { 475 struct iio_dev *indio_dev; 476 struct ad5064_state *st; 477 unsigned int midscale; 478 unsigned int i; 479 int ret; 480 481 indio_dev = devm_iio_device_alloc(dev, sizeof(*st)); 482 if (indio_dev == NULL) 483 return -ENOMEM; 484 485 st = iio_priv(indio_dev); 486 dev_set_drvdata(dev, indio_dev); 487 488 st->chip_info = &ad5064_chip_info_tbl[type]; 489 st->dev = dev; 490 st->write = write; 491 492 for (i = 0; i < ad5064_num_vref(st); ++i) 493 st->vref_reg[i].supply = ad5064_vref_name(st, i); 494 495 ret = devm_regulator_bulk_get(dev, ad5064_num_vref(st), 496 st->vref_reg); 497 if (ret) { 498 if (!st->chip_info->internal_vref) 499 return ret; 500 st->use_internal_vref = true; 501 ret = ad5064_write(st, AD5064_CMD_CONFIG, 0, 502 AD5064_CONFIG_INT_VREF_ENABLE, 0); 503 if (ret) { 504 dev_err(dev, "Failed to enable internal vref: %d\n", 505 ret); 506 return ret; 507 } 508 } else { 509 ret = regulator_bulk_enable(ad5064_num_vref(st), st->vref_reg); 510 if (ret) 511 return ret; 512 } 513 514 indio_dev->dev.parent = dev; 515 indio_dev->name = name; 516 indio_dev->info = &ad5064_info; 517 indio_dev->modes = INDIO_DIRECT_MODE; 518 indio_dev->channels = st->chip_info->channels; 519 indio_dev->num_channels = st->chip_info->num_channels; 520 521 midscale = (1 << indio_dev->channels[0].scan_type.realbits) / 2; 522 523 for (i = 0; i < st->chip_info->num_channels; ++i) { 524 st->pwr_down_mode[i] = AD5064_LDAC_PWRDN_1K; 525 st->dac_cache[i] = midscale; 526 } 527 528 ret = iio_device_register(indio_dev); 529 if (ret) 530 goto error_disable_reg; 531 532 return 0; 533 534 error_disable_reg: 535 if (!st->use_internal_vref) 536 regulator_bulk_disable(ad5064_num_vref(st), st->vref_reg); 537 538 return ret; 539 } 540 541 static int ad5064_remove(struct device *dev) 542 { 543 struct iio_dev *indio_dev = dev_get_drvdata(dev); 544 struct ad5064_state *st = iio_priv(indio_dev); 545 546 iio_device_unregister(indio_dev); 547 548 if (!st->use_internal_vref) 549 regulator_bulk_disable(ad5064_num_vref(st), st->vref_reg); 550 551 return 0; 552 } 553 554 #if IS_ENABLED(CONFIG_SPI_MASTER) 555 556 static int ad5064_spi_write(struct ad5064_state *st, unsigned int cmd, 557 unsigned int addr, unsigned int val) 558 { 559 struct spi_device *spi = to_spi_device(st->dev); 560 561 st->data.spi = cpu_to_be32(AD5064_CMD(cmd) | AD5064_ADDR(addr) | val); 562 return spi_write(spi, &st->data.spi, sizeof(st->data.spi)); 563 } 564 565 static int ad5064_spi_probe(struct spi_device *spi) 566 { 567 const struct spi_device_id *id = spi_get_device_id(spi); 568 569 return ad5064_probe(&spi->dev, id->driver_data, id->name, 570 ad5064_spi_write); 571 } 572 573 static int ad5064_spi_remove(struct spi_device *spi) 574 { 575 return ad5064_remove(&spi->dev); 576 } 577 578 static const struct spi_device_id ad5064_spi_ids[] = { 579 {"ad5024", ID_AD5024}, 580 {"ad5025", ID_AD5025}, 581 {"ad5044", ID_AD5044}, 582 {"ad5045", ID_AD5045}, 583 {"ad5064", ID_AD5064}, 584 {"ad5064-1", ID_AD5064_1}, 585 {"ad5065", ID_AD5065}, 586 {"ad5628-1", ID_AD5628_1}, 587 {"ad5628-2", ID_AD5628_2}, 588 {"ad5648-1", ID_AD5648_1}, 589 {"ad5648-2", ID_AD5648_2}, 590 {"ad5666-1", ID_AD5666_1}, 591 {"ad5666-2", ID_AD5666_2}, 592 {"ad5668-1", ID_AD5668_1}, 593 {"ad5668-2", ID_AD5668_2}, 594 {"ad5668-3", ID_AD5668_2}, /* similar enough to ad5668-2 */ 595 {} 596 }; 597 MODULE_DEVICE_TABLE(spi, ad5064_spi_ids); 598 599 static struct spi_driver ad5064_spi_driver = { 600 .driver = { 601 .name = "ad5064", 602 }, 603 .probe = ad5064_spi_probe, 604 .remove = ad5064_spi_remove, 605 .id_table = ad5064_spi_ids, 606 }; 607 608 static int __init ad5064_spi_register_driver(void) 609 { 610 return spi_register_driver(&ad5064_spi_driver); 611 } 612 613 static void ad5064_spi_unregister_driver(void) 614 { 615 spi_unregister_driver(&ad5064_spi_driver); 616 } 617 618 #else 619 620 static inline int ad5064_spi_register_driver(void) { return 0; } 621 static inline void ad5064_spi_unregister_driver(void) { } 622 623 #endif 624 625 #if IS_ENABLED(CONFIG_I2C) 626 627 static int ad5064_i2c_write(struct ad5064_state *st, unsigned int cmd, 628 unsigned int addr, unsigned int val) 629 { 630 struct i2c_client *i2c = to_i2c_client(st->dev); 631 int ret; 632 633 st->data.i2c[0] = (cmd << 4) | addr; 634 put_unaligned_be16(val, &st->data.i2c[1]); 635 636 ret = i2c_master_send(i2c, st->data.i2c, 3); 637 if (ret < 0) 638 return ret; 639 640 return 0; 641 } 642 643 static int ad5064_i2c_probe(struct i2c_client *i2c, 644 const struct i2c_device_id *id) 645 { 646 return ad5064_probe(&i2c->dev, id->driver_data, id->name, 647 ad5064_i2c_write); 648 } 649 650 static int ad5064_i2c_remove(struct i2c_client *i2c) 651 { 652 return ad5064_remove(&i2c->dev); 653 } 654 655 static const struct i2c_device_id ad5064_i2c_ids[] = { 656 {"ad5629-1", ID_AD5629_1}, 657 {"ad5629-2", ID_AD5629_2}, 658 {"ad5629-3", ID_AD5629_2}, /* similar enough to ad5629-2 */ 659 {"ad5669-1", ID_AD5669_1}, 660 {"ad5669-2", ID_AD5669_2}, 661 {"ad5669-3", ID_AD5669_2}, /* similar enough to ad5669-2 */ 662 {} 663 }; 664 MODULE_DEVICE_TABLE(i2c, ad5064_i2c_ids); 665 666 static struct i2c_driver ad5064_i2c_driver = { 667 .driver = { 668 .name = "ad5064", 669 }, 670 .probe = ad5064_i2c_probe, 671 .remove = ad5064_i2c_remove, 672 .id_table = ad5064_i2c_ids, 673 }; 674 675 static int __init ad5064_i2c_register_driver(void) 676 { 677 return i2c_add_driver(&ad5064_i2c_driver); 678 } 679 680 static void __exit ad5064_i2c_unregister_driver(void) 681 { 682 i2c_del_driver(&ad5064_i2c_driver); 683 } 684 685 #else 686 687 static inline int ad5064_i2c_register_driver(void) { return 0; } 688 static inline void ad5064_i2c_unregister_driver(void) { } 689 690 #endif 691 692 static int __init ad5064_init(void) 693 { 694 int ret; 695 696 ret = ad5064_spi_register_driver(); 697 if (ret) 698 return ret; 699 700 ret = ad5064_i2c_register_driver(); 701 if (ret) { 702 ad5064_spi_unregister_driver(); 703 return ret; 704 } 705 706 return 0; 707 } 708 module_init(ad5064_init); 709 710 static void __exit ad5064_exit(void) 711 { 712 ad5064_i2c_unregister_driver(); 713 ad5064_spi_unregister_driver(); 714 } 715 module_exit(ad5064_exit); 716 717 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>"); 718 MODULE_DESCRIPTION("Analog Devices AD5024 and similar multi-channel DACs"); 719 MODULE_LICENSE("GPL v2"); 720