drivers/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 <linux/iio/iio.h>
  22 #include <linux/iio/sysfs.h>
  23
  24 #define AD5380_REG_DATA(x)      (((x) << 2) | 3)
  25 #define AD5380_REG_OFFSET(x)    (((x) << 2) | 2)
  26 #define AD5380_REG_GAIN(x)      (((x) << 2) | 1)
  27 #define AD5380_REG_SF_PWR_DOWN  (8 << 2)
  28 #define AD5380_REG_SF_PWR_UP    (9 << 2)
  29 #define AD5380_REG_SF_CTRL      (12 << 2)
  30
  31 #define AD5380_CTRL_PWR_DOWN_MODE_OFFSET        13
  32 #define AD5380_CTRL_INT_VREF_2V5                BIT(12)
  33 #define AD5380_CTRL_INT_VREF_EN                 BIT(10)
  34
  35 /**
  36  * struct ad5380_chip_info - chip specific information
  37  * @channel_template:   channel specification template
  38  * @num_channels:       number of channels
  39  * @int_vref:           internal vref in uV
  40 */
  41
  42 struct ad5380_chip_info {
  43         struct iio_chan_spec    channel_template;
  44         unsigned int            num_channels;
  45         unsigned int            int_vref;
  46 };
  47
  48 /**
  49  * struct ad5380_state - driver instance specific data
  50  * @regmap:             regmap instance used by the device
  51  * @chip_info:          chip model specific constants, available modes etc
  52  * @vref_reg:           vref supply regulator
  53  * @vref:               actual reference voltage used in uA
  54  * @pwr_down:           whether the chip is currently in power down mode
  55  */
  56
  57 struct ad5380_state {
  58         struct regmap                   *regmap;
  59         const struct ad5380_chip_info   *chip_info;
  60         struct regulator                *vref_reg;
  61         int                             vref;
  62         bool                            pwr_down;
  63 };
  64
  65 enum ad5380_type {
  66         ID_AD5380_3,
  67         ID_AD5380_5,
  68         ID_AD5381_3,
  69         ID_AD5381_5,
  70         ID_AD5382_3,
  71         ID_AD5382_5,
  72         ID_AD5383_3,
  73         ID_AD5383_5,
  74         ID_AD5390_3,
  75         ID_AD5390_5,
  76         ID_AD5391_3,
  77         ID_AD5391_5,
  78         ID_AD5392_3,
  79         ID_AD5392_5,
  80 };
  81
  82 static ssize_t ad5380_read_dac_powerdown(struct iio_dev *indio_dev,
  83         uintptr_t private, const struct iio_chan_spec *chan, char *buf)
  84 {
  85         struct ad5380_state *st = iio_priv(indio_dev);
  86
  87         return sprintf(buf, "%d\n", st->pwr_down);
  88 }
  89
  90 static ssize_t ad5380_write_dac_powerdown(struct iio_dev *indio_dev,
  91          uintptr_t private, const struct iio_chan_spec *chan, const char *buf,
  92          size_t len)
  93 {
  94         struct ad5380_state *st = iio_priv(indio_dev);
  95         bool pwr_down;
  96         int ret;
  97
  98         ret = strtobool(buf, &pwr_down);
  99         if (ret)
 100                 return ret;
 101
 102         mutex_lock(&indio_dev->mlock);
 103
 104         if (pwr_down)
 105                 ret = regmap_write(st->regmap, AD5380_REG_SF_PWR_DOWN, 0);
 106         else
 107                 ret = regmap_write(st->regmap, AD5380_REG_SF_PWR_UP, 0);
 108
 109         st->pwr_down = pwr_down;
 110
 111         mutex_unlock(&indio_dev->mlock);
 112
 113         return ret ? ret : len;
 114 }
 115
 116 static const char * const ad5380_powerdown_modes[] = {
 117         "100kohm_to_gnd",
 118         "three_state",
 119 };
 120
 121 static int ad5380_get_powerdown_mode(struct iio_dev *indio_dev,
 122         const struct iio_chan_spec *chan)
 123 {
 124         struct ad5380_state *st = iio_priv(indio_dev);
 125         unsigned int mode;
 126         int ret;
 127
 128         ret = regmap_read(st->regmap, AD5380_REG_SF_CTRL, &mode);
 129         if (ret)
 130                 return ret;
 131
 132         mode = (mode >> AD5380_CTRL_PWR_DOWN_MODE_OFFSET) & 1;
 133
 134         return mode;
 135 }
 136
 137 static int ad5380_set_powerdown_mode(struct iio_dev *indio_dev,
 138         const struct iio_chan_spec *chan, unsigned int mode)
 139 {
 140         struct ad5380_state *st = iio_priv(indio_dev);
 141         int ret;
 142
 143         ret = regmap_update_bits(st->regmap, AD5380_REG_SF_CTRL,
 144                 1 << AD5380_CTRL_PWR_DOWN_MODE_OFFSET,
 145                 mode << AD5380_CTRL_PWR_DOWN_MODE_OFFSET);
 146
 147         return ret;
 148 }
 149
 150 static const struct iio_enum ad5380_powerdown_mode_enum = {
 151         .items = ad5380_powerdown_modes,
 152         .num_items = ARRAY_SIZE(ad5380_powerdown_modes),
 153         .get = ad5380_get_powerdown_mode,
 154         .set = ad5380_set_powerdown_mode,
 155 };
 156
 157 static unsigned int ad5380_info_to_reg(struct iio_chan_spec const *chan,
 158         long info)
 159 {
 160         switch (info) {
 161         case 0:
 162                 return AD5380_REG_DATA(chan->address);
 163         case IIO_CHAN_INFO_CALIBBIAS:
 164                 return AD5380_REG_OFFSET(chan->address);
 165         case IIO_CHAN_INFO_CALIBSCALE:
 166                 return AD5380_REG_GAIN(chan->address);
 167         default:
 168                 break;
 169         }
 170
 171         return 0;
 172 }
 173
 174 static int ad5380_write_raw(struct iio_dev *indio_dev,
 175         struct iio_chan_spec const *chan, int val, int val2, long info)
 176 {
 177         const unsigned int max_val = (1 << chan->scan_type.realbits);
 178         struct ad5380_state *st = iio_priv(indio_dev);
 179
 180         switch (info) {
 181         case IIO_CHAN_INFO_RAW:
 182         case IIO_CHAN_INFO_CALIBSCALE:
 183                 if (val >= max_val || val < 0)
 184                         return -EINVAL;
 185
 186                 return regmap_write(st->regmap,
 187                         ad5380_info_to_reg(chan, info),
 188                         val << chan->scan_type.shift);
 189         case IIO_CHAN_INFO_CALIBBIAS:
 190                 val += (1 << chan->scan_type.realbits) / 2;
 191                 if (val >= max_val || val < 0)
 192                         return -EINVAL;
 193
 194                 return regmap_write(st->regmap,
 195                         AD5380_REG_OFFSET(chan->address),
 196                         val << chan->scan_type.shift);
 197         default:
 198                 break;
 199         }
 200         return -EINVAL;
 201 }
 202
 203 static int ad5380_read_raw(struct iio_dev *indio_dev,
 204         struct iio_chan_spec const *chan, int *val, int *val2, long info)
 205 {
 206         struct ad5380_state *st = iio_priv(indio_dev);
 207         int ret;
 208
 209         switch (info) {
 210         case IIO_CHAN_INFO_RAW:
 211         case IIO_CHAN_INFO_CALIBSCALE:
 212                 ret = regmap_read(st->regmap, ad5380_info_to_reg(chan, info),
 213                                         val);
 214                 if (ret)
 215                         return ret;
 216                 *val >>= chan->scan_type.shift;
 217                 return IIO_VAL_INT;
 218         case IIO_CHAN_INFO_CALIBBIAS:
 219                 ret = regmap_read(st->regmap, AD5380_REG_OFFSET(chan->address),
 220                                         val);
 221                 if (ret)
 222                         return ret;
 223                 *val >>= chan->scan_type.shift;
 224                 val -= (1 << chan->scan_type.realbits) / 2;
 225                 return IIO_VAL_INT;
 226         case IIO_CHAN_INFO_SCALE:
 227                 *val = 2 * st->vref;
 228                 *val2 = chan->scan_type.realbits;
 229                 return IIO_VAL_FRACTIONAL_LOG2;
 230         default:
 231                 break;
 232         }
 233
 234         return -EINVAL;
 235 }
 236
 237 static const struct iio_info ad5380_info = {
 238         .read_raw = ad5380_read_raw,
 239         .write_raw = ad5380_write_raw,
 240 };
 241
 242 static struct iio_chan_spec_ext_info ad5380_ext_info[] = {
 243         {
 244                 .name = "powerdown",
 245                 .read = ad5380_read_dac_powerdown,
 246                 .write = ad5380_write_dac_powerdown,
 247                 .shared = IIO_SEPARATE,
 248         },
 249         IIO_ENUM("powerdown_mode", IIO_SHARED_BY_TYPE,
 250                  &ad5380_powerdown_mode_enum),
 251         IIO_ENUM_AVAILABLE("powerdown_mode", &ad5380_powerdown_mode_enum),
 252         { },
 253 };
 254
 255 #define AD5380_CHANNEL(_bits) {                                 \
 256         .type = IIO_VOLTAGE,                                    \
 257         .indexed = 1,                                           \
 258         .output = 1,                                            \
 259         .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |          \
 260                 BIT(IIO_CHAN_INFO_CALIBSCALE) |                 \
 261                 BIT(IIO_CHAN_INFO_CALIBBIAS),                   \
 262         .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),   \
 263         .scan_type = {                                          \
 264                 .sign = 'u',                                    \
 265                 .realbits = (_bits),                            \
 266                 .storagebits =  16,                             \
 267                 .shift = 14 - (_bits),                          \
 268         },                                                      \
 269         .ext_info = ad5380_ext_info,                            \
 270 }
 271
 272 static const struct ad5380_chip_info ad5380_chip_info_tbl[] = {
 273         [ID_AD5380_3] = {
 274                 .channel_template = AD5380_CHANNEL(14),
 275                 .num_channels = 40,
 276                 .int_vref = 1250,
 277         },
 278         [ID_AD5380_5] = {
 279                 .channel_template = AD5380_CHANNEL(14),
 280                 .num_channels = 40,
 281                 .int_vref = 2500,
 282         },
 283         [ID_AD5381_3] = {
 284                 .channel_template = AD5380_CHANNEL(12),
 285                 .num_channels = 16,
 286                 .int_vref = 1250,
 287         },
 288         [ID_AD5381_5] = {
 289                 .channel_template = AD5380_CHANNEL(12),
 290                 .num_channels = 16,
 291                 .int_vref = 2500,
 292         },
 293         [ID_AD5382_3] = {
 294                 .channel_template = AD5380_CHANNEL(14),
 295                 .num_channels = 32,
 296                 .int_vref = 1250,
 297         },
 298         [ID_AD5382_5] = {
 299                 .channel_template = AD5380_CHANNEL(14),
 300                 .num_channels = 32,
 301                 .int_vref = 2500,
 302         },
 303         [ID_AD5383_3] = {
 304                 .channel_template = AD5380_CHANNEL(12),
 305                 .num_channels = 32,
 306                 .int_vref = 1250,
 307         },
 308         [ID_AD5383_5] = {
 309                 .channel_template = AD5380_CHANNEL(12),
 310                 .num_channels = 32,
 311                 .int_vref = 2500,
 312         },
 313         [ID_AD5390_3] = {
 314                 .channel_template = AD5380_CHANNEL(14),
 315                 .num_channels = 16,
 316                 .int_vref = 1250,
 317         },
 318         [ID_AD5390_5] = {
 319                 .channel_template = AD5380_CHANNEL(14),
 320                 .num_channels = 16,
 321                 .int_vref = 2500,
 322         },
 323         [ID_AD5391_3] = {
 324                 .channel_template = AD5380_CHANNEL(12),
 325                 .num_channels = 16,
 326                 .int_vref = 1250,
 327         },
 328         [ID_AD5391_5] = {
 329                 .channel_template = AD5380_CHANNEL(12),
 330                 .num_channels = 16,
 331                 .int_vref = 2500,
 332         },
 333         [ID_AD5392_3] = {
 334                 .channel_template = AD5380_CHANNEL(14),
 335                 .num_channels = 8,
 336                 .int_vref = 1250,
 337         },
 338         [ID_AD5392_5] = {
 339                 .channel_template = AD5380_CHANNEL(14),
 340                 .num_channels = 8,
 341                 .int_vref = 2500,
 342         },
 343 };
 344
 345 static int ad5380_alloc_channels(struct iio_dev *indio_dev)
 346 {
 347         struct ad5380_state *st = iio_priv(indio_dev);
 348         struct iio_chan_spec *channels;
 349         unsigned int i;
 350
 351         channels = kcalloc(st->chip_info->num_channels,
 352                            sizeof(struct iio_chan_spec), GFP_KERNEL);
 353
 354         if (!channels)
 355                 return -ENOMEM;
 356
 357         for (i = 0; i < st->chip_info->num_channels; ++i) {
 358                 channels[i] = st->chip_info->channel_template;
 359                 channels[i].channel = i;
 360                 channels[i].address = i;
 361         }
 362
 363         indio_dev->channels = channels;
 364
 365         return 0;
 366 }
 367
 368 static int ad5380_probe(struct device *dev, struct regmap *regmap,
 369                         enum ad5380_type type, const char *name)
 370 {
 371         struct iio_dev *indio_dev;
 372         struct ad5380_state *st;
 373         unsigned int ctrl = 0;
 374         int ret;
 375
 376         indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
 377         if (indio_dev == NULL) {
 378                 dev_err(dev, "Failed to allocate iio device\n");
 379                 return -ENOMEM;
 380         }
 381
 382         st = iio_priv(indio_dev);
 383         dev_set_drvdata(dev, indio_dev);
 384
 385         st->chip_info = &ad5380_chip_info_tbl[type];
 386         st->regmap = regmap;
 387
 388         indio_dev->dev.parent = dev;
 389         indio_dev->name = name;
 390         indio_dev->info = &ad5380_info;
 391         indio_dev->modes = INDIO_DIRECT_MODE;
 392         indio_dev->num_channels = st->chip_info->num_channels;
 393
 394         ret = ad5380_alloc_channels(indio_dev);
 395         if (ret) {
 396                 dev_err(dev, "Failed to allocate channel spec: %d\n", ret);
 397                 return ret;
 398         }
 399
 400         if (st->chip_info->int_vref == 2500)
 401                 ctrl |= AD5380_CTRL_INT_VREF_2V5;
 402
 403         st->vref_reg = devm_regulator_get(dev, "vref");
 404         if (!IS_ERR(st->vref_reg)) {
 405                 ret = regulator_enable(st->vref_reg);
 406                 if (ret) {
 407                         dev_err(dev, "Failed to enable vref regulators: %d\n",
 408                                 ret);
 409                         goto error_free_reg;
 410                 }
 411
 412                 ret = regulator_get_voltage(st->vref_reg);
 413                 if (ret < 0)
 414                         goto error_disable_reg;
 415
 416                 st->vref = ret / 1000;
 417         } else {
 418                 st->vref = st->chip_info->int_vref;
 419                 ctrl |= AD5380_CTRL_INT_VREF_EN;
 420         }
 421
 422         ret = regmap_write(st->regmap, AD5380_REG_SF_CTRL, ctrl);
 423         if (ret) {
 424                 dev_err(dev, "Failed to write to device: %d\n", ret);
 425                 goto error_disable_reg;
 426         }
 427
 428         ret = iio_device_register(indio_dev);
 429         if (ret) {
 430                 dev_err(dev, "Failed to register iio device: %d\n", ret);
 431                 goto error_disable_reg;
 432         }
 433
 434         return 0;
 435
 436 error_disable_reg:
 437         if (!IS_ERR(st->vref_reg))
 438                 regulator_disable(st->vref_reg);
 439 error_free_reg:
 440         kfree(indio_dev->channels);
 441
 442         return ret;
 443 }
 444
 445 static int ad5380_remove(struct device *dev)
 446 {
 447         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 448         struct ad5380_state *st = iio_priv(indio_dev);
 449
 450         iio_device_unregister(indio_dev);
 451
 452         kfree(indio_dev->channels);
 453
 454         if (!IS_ERR(st->vref_reg)) {
 455                 regulator_disable(st->vref_reg);
 456         }
 457
 458         return 0;
 459 }
 460
 461 static bool ad5380_reg_false(struct device *dev, unsigned int reg)
 462 {
 463         return false;
 464 }
 465
 466 static const struct regmap_config ad5380_regmap_config = {
 467         .reg_bits = 10,
 468         .val_bits = 14,
 469
 470         .max_register = AD5380_REG_DATA(40),
 471         .cache_type = REGCACHE_RBTREE,
 472
 473         .volatile_reg = ad5380_reg_false,
 474         .readable_reg = ad5380_reg_false,
 475 };
 476
 477 #if IS_ENABLED(CONFIG_SPI_MASTER)
 478
 479 static int ad5380_spi_probe(struct spi_device *spi)
 480 {
 481         const struct spi_device_id *id = spi_get_device_id(spi);
 482         struct regmap *regmap;
 483
 484         regmap = devm_regmap_init_spi(spi, &ad5380_regmap_config);
 485
 486         if (IS_ERR(regmap))
 487                 return PTR_ERR(regmap);
 488
 489         return ad5380_probe(&spi->dev, regmap, id->driver_data, id->name);
 490 }
 491
 492 static int ad5380_spi_remove(struct spi_device *spi)
 493 {
 494         return ad5380_remove(&spi->dev);
 495 }
 496
 497 static const struct spi_device_id ad5380_spi_ids[] = {
 498         { "ad5380-3", ID_AD5380_3 },
 499         { "ad5380-5", ID_AD5380_5 },
 500         { "ad5381-3", ID_AD5381_3 },
 501         { "ad5381-5", ID_AD5381_5 },
 502         { "ad5382-3", ID_AD5382_3 },
 503         { "ad5382-5", ID_AD5382_5 },
 504         { "ad5383-3", ID_AD5383_3 },
 505         { "ad5383-5", ID_AD5383_5 },
 506         { "ad5384-3", ID_AD5380_3 },
 507         { "ad5384-5", ID_AD5380_5 },
 508         { "ad5390-3", ID_AD5390_3 },
 509         { "ad5390-5", ID_AD5390_5 },
 510         { "ad5391-3", ID_AD5391_3 },
 511         { "ad5391-5", ID_AD5391_5 },
 512         { "ad5392-3", ID_AD5392_3 },
 513         { "ad5392-5", ID_AD5392_5 },
 514         { }
 515 };
 516 MODULE_DEVICE_TABLE(spi, ad5380_spi_ids);
 517
 518 static struct spi_driver ad5380_spi_driver = {
 519         .driver = {
 520                    .name = "ad5380",
 521         },
 522         .probe = ad5380_spi_probe,
 523         .remove = ad5380_spi_remove,
 524         .id_table = ad5380_spi_ids,
 525 };
 526
 527 static inline int ad5380_spi_register_driver(void)
 528 {
 529         return spi_register_driver(&ad5380_spi_driver);
 530 }
 531
 532 static inline void ad5380_spi_unregister_driver(void)
 533 {
 534         spi_unregister_driver(&ad5380_spi_driver);
 535 }
 536
 537 #else
 538
 539 static inline int ad5380_spi_register_driver(void)
 540 {
 541         return 0;
 542 }
 543
 544 static inline void ad5380_spi_unregister_driver(void)
 545 {
 546 }
 547
 548 #endif
 549
 550 #if IS_ENABLED(CONFIG_I2C)
 551
 552 static int ad5380_i2c_probe(struct i2c_client *i2c,
 553                             const struct i2c_device_id *id)
 554 {
 555         struct regmap *regmap;
 556
 557         regmap = devm_regmap_init_i2c(i2c, &ad5380_regmap_config);
 558
 559         if (IS_ERR(regmap))
 560                 return PTR_ERR(regmap);
 561
 562         return ad5380_probe(&i2c->dev, regmap, id->driver_data, id->name);
 563 }
 564
 565 static int ad5380_i2c_remove(struct i2c_client *i2c)
 566 {
 567         return ad5380_remove(&i2c->dev);
 568 }
 569
 570 static const struct i2c_device_id ad5380_i2c_ids[] = {
 571         { "ad5380-3", ID_AD5380_3 },
 572         { "ad5380-5", ID_AD5380_5 },
 573         { "ad5381-3", ID_AD5381_3 },
 574         { "ad5381-5", ID_AD5381_5 },
 575         { "ad5382-3", ID_AD5382_3 },
 576         { "ad5382-5", ID_AD5382_5 },
 577         { "ad5383-3", ID_AD5383_3 },
 578         { "ad5383-5", ID_AD5383_5 },
 579         { "ad5384-3", ID_AD5380_3 },
 580         { "ad5384-5", ID_AD5380_5 },
 581         { "ad5390-3", ID_AD5390_3 },
 582         { "ad5390-5", ID_AD5390_5 },
 583         { "ad5391-3", ID_AD5391_3 },
 584         { "ad5391-5", ID_AD5391_5 },
 585         { "ad5392-3", ID_AD5392_3 },
 586         { "ad5392-5", ID_AD5392_5 },
 587         { }
 588 };
 589 MODULE_DEVICE_TABLE(i2c, ad5380_i2c_ids);
 590
 591 static struct i2c_driver ad5380_i2c_driver = {
 592         .driver = {
 593                    .name = "ad5380",
 594         },
 595         .probe = ad5380_i2c_probe,
 596         .remove = ad5380_i2c_remove,
 597         .id_table = ad5380_i2c_ids,
 598 };
 599
 600 static inline int ad5380_i2c_register_driver(void)
 601 {
 602         return i2c_add_driver(&ad5380_i2c_driver);
 603 }
 604
 605 static inline void ad5380_i2c_unregister_driver(void)
 606 {
 607         i2c_del_driver(&ad5380_i2c_driver);
 608 }
 609
 610 #else
 611
 612 static inline int ad5380_i2c_register_driver(void)
 613 {
 614         return 0;
 615 }
 616
 617 static inline void ad5380_i2c_unregister_driver(void)
 618 {
 619 }
 620
 621 #endif
 622
 623 static int __init ad5380_spi_init(void)
 624 {
 625         int ret;
 626
 627         ret = ad5380_spi_register_driver();
 628         if (ret)
 629                 return ret;
 630
 631         ret = ad5380_i2c_register_driver();
 632         if (ret) {
 633                 ad5380_spi_unregister_driver();
 634                 return ret;
 635         }
 636
 637         return 0;
 638 }
 639 module_init(ad5380_spi_init);
 640
 641 static void __exit ad5380_spi_exit(void)
 642 {
 643         ad5380_i2c_unregister_driver();
 644         ad5380_spi_unregister_driver();
 645
 646 }
 647 module_exit(ad5380_spi_exit);
 648
 649 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
 650 MODULE_DESCRIPTION("Analog Devices AD5380/81/82/83/84/90/91/92 DAC");
 651 MODULE_LICENSE("GPL v2");