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         unsigned long scale_uv;
 208         int ret;
 209
 210         switch (info) {
 211         case IIO_CHAN_INFO_RAW:
 212         case IIO_CHAN_INFO_CALIBSCALE:
 213                 ret = regmap_read(st->regmap, ad5380_info_to_reg(chan, info),
 214                                         val);
 215                 if (ret)
 216                         return ret;
 217                 *val >>= chan->scan_type.shift;
 218                 return IIO_VAL_INT;
 219         case IIO_CHAN_INFO_CALIBBIAS:
 220                 ret = regmap_read(st->regmap, AD5380_REG_OFFSET(chan->address),
 221                                         val);
 222                 if (ret)
 223                         return ret;
 224                 *val >>= chan->scan_type.shift;
 225                 val -= (1 << chan->scan_type.realbits) / 2;
 226                 return IIO_VAL_INT;
 227         case IIO_CHAN_INFO_SCALE:
 228                 scale_uv = ((2 * st->vref) >> chan->scan_type.realbits) * 100;
 229                 *val =  scale_uv / 100000;
 230                 *val2 = (scale_uv % 100000) * 10;
 231                 return IIO_VAL_INT_PLUS_MICRO;
 232         default:
 233                 break;
 234         }
 235
 236         return -EINVAL;
 237 }
 238
 239 static const struct iio_info ad5380_info = {
 240         .read_raw = ad5380_read_raw,
 241         .write_raw = ad5380_write_raw,
 242         .driver_module = THIS_MODULE,
 243 };
 244
 245 static struct iio_chan_spec_ext_info ad5380_ext_info[] = {
 246         {
 247                 .name = "powerdown",
 248                 .read = ad5380_read_dac_powerdown,
 249                 .write = ad5380_write_dac_powerdown,
 250         },
 251         IIO_ENUM("powerdown_mode", true, &ad5380_powerdown_mode_enum),
 252         IIO_ENUM_AVAILABLE("powerdown_mode", &ad5380_powerdown_mode_enum),
 253         { },
 254 };
 255
 256 #define AD5380_CHANNEL(_bits) {                                 \
 257         .type = IIO_VOLTAGE,                                    \
 258         .indexed = 1,                                           \
 259         .output = 1,                                            \
 260         .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |          \
 261                 BIT(IIO_CHAN_INFO_CALIBSCALE) |                 \
 262                 BIT(IIO_CHAN_INFO_CALIBBIAS),                   \
 263         .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),   \
 264         .scan_type = IIO_ST('u', (_bits), 16, 14 - (_bits)),    \
 265         .ext_info = ad5380_ext_info,                            \
 266 }
 267
 268 static const struct ad5380_chip_info ad5380_chip_info_tbl[] = {
 269         [ID_AD5380_3] = {
 270                 .channel_template = AD5380_CHANNEL(14),
 271                 .num_channels = 40,
 272                 .int_vref = 1250000,
 273         },
 274         [ID_AD5380_5] = {
 275                 .channel_template = AD5380_CHANNEL(14),
 276                 .num_channels = 40,
 277                 .int_vref = 2500000,
 278         },
 279         [ID_AD5381_3] = {
 280                 .channel_template = AD5380_CHANNEL(12),
 281                 .num_channels = 16,
 282                 .int_vref = 1250000,
 283         },
 284         [ID_AD5381_5] = {
 285                 .channel_template = AD5380_CHANNEL(12),
 286                 .num_channels = 16,
 287                 .int_vref = 2500000,
 288         },
 289         [ID_AD5382_3] = {
 290                 .channel_template = AD5380_CHANNEL(14),
 291                 .num_channels = 32,
 292                 .int_vref = 1250000,
 293         },
 294         [ID_AD5382_5] = {
 295                 .channel_template = AD5380_CHANNEL(14),
 296                 .num_channels = 32,
 297                 .int_vref = 2500000,
 298         },
 299         [ID_AD5383_3] = {
 300                 .channel_template = AD5380_CHANNEL(12),
 301                 .num_channels = 32,
 302                 .int_vref = 1250000,
 303         },
 304         [ID_AD5383_5] = {
 305                 .channel_template = AD5380_CHANNEL(12),
 306                 .num_channels = 32,
 307                 .int_vref = 2500000,
 308         },
 309         [ID_AD5390_3] = {
 310                 .channel_template = AD5380_CHANNEL(14),
 311                 .num_channels = 16,
 312                 .int_vref = 1250000,
 313         },
 314         [ID_AD5390_5] = {
 315                 .channel_template = AD5380_CHANNEL(14),
 316                 .num_channels = 16,
 317                 .int_vref = 2500000,
 318         },
 319         [ID_AD5391_3] = {
 320                 .channel_template = AD5380_CHANNEL(12),
 321                 .num_channels = 16,
 322                 .int_vref = 1250000,
 323         },
 324         [ID_AD5391_5] = {
 325                 .channel_template = AD5380_CHANNEL(12),
 326                 .num_channels = 16,
 327                 .int_vref = 2500000,
 328         },
 329         [ID_AD5392_3] = {
 330                 .channel_template = AD5380_CHANNEL(14),
 331                 .num_channels = 8,
 332                 .int_vref = 1250000,
 333         },
 334         [ID_AD5392_5] = {
 335                 .channel_template = AD5380_CHANNEL(14),
 336                 .num_channels = 8,
 337                 .int_vref = 2500000,
 338         },
 339 };
 340
 341 static int ad5380_alloc_channels(struct iio_dev *indio_dev)
 342 {
 343         struct ad5380_state *st = iio_priv(indio_dev);
 344         struct iio_chan_spec *channels;
 345         unsigned int i;
 346
 347         channels = kcalloc(st->chip_info->num_channels,
 348                            sizeof(struct iio_chan_spec), GFP_KERNEL);
 349
 350         if (!channels)
 351                 return -ENOMEM;
 352
 353         for (i = 0; i < st->chip_info->num_channels; ++i) {
 354                 channels[i] = st->chip_info->channel_template;
 355                 channels[i].channel = i;
 356                 channels[i].address = i;
 357         }
 358
 359         indio_dev->channels = channels;
 360
 361         return 0;
 362 }
 363
 364 static int ad5380_probe(struct device *dev, struct regmap *regmap,
 365                         enum ad5380_type type, const char *name)
 366 {
 367         struct iio_dev *indio_dev;
 368         struct ad5380_state *st;
 369         unsigned int ctrl = 0;
 370         int ret;
 371
 372         indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
 373         if (indio_dev == NULL) {
 374                 dev_err(dev, "Failed to allocate iio device\n");
 375                 return -ENOMEM;
 376         }
 377
 378         st = iio_priv(indio_dev);
 379         dev_set_drvdata(dev, indio_dev);
 380
 381         st->chip_info = &ad5380_chip_info_tbl[type];
 382         st->regmap = regmap;
 383
 384         indio_dev->dev.parent = dev;
 385         indio_dev->name = name;
 386         indio_dev->info = &ad5380_info;
 387         indio_dev->modes = INDIO_DIRECT_MODE;
 388         indio_dev->num_channels = st->chip_info->num_channels;
 389
 390         ret = ad5380_alloc_channels(indio_dev);
 391         if (ret) {
 392                 dev_err(dev, "Failed to allocate channel spec: %d\n", ret);
 393                 return ret;
 394         }
 395
 396         if (st->chip_info->int_vref == 2500000)
 397                 ctrl |= AD5380_CTRL_INT_VREF_2V5;
 398
 399         st->vref_reg = devm_regulator_get(dev, "vref");
 400         if (!IS_ERR(st->vref_reg)) {
 401                 ret = regulator_enable(st->vref_reg);
 402                 if (ret) {
 403                         dev_err(dev, "Failed to enable vref regulators: %d\n",
 404                                 ret);
 405                         goto error_free_reg;
 406                 }
 407
 408                 ret = regulator_get_voltage(st->vref_reg);
 409                 if (ret < 0)
 410                         goto error_disable_reg;
 411
 412                 st->vref = ret;
 413         } else {
 414                 st->vref = st->chip_info->int_vref;
 415                 ctrl |= AD5380_CTRL_INT_VREF_EN;
 416         }
 417
 418         ret = regmap_write(st->regmap, AD5380_REG_SF_CTRL, ctrl);
 419         if (ret) {
 420                 dev_err(dev, "Failed to write to device: %d\n", ret);
 421                 goto error_disable_reg;
 422         }
 423
 424         ret = iio_device_register(indio_dev);
 425         if (ret) {
 426                 dev_err(dev, "Failed to register iio device: %d\n", ret);
 427                 goto error_disable_reg;
 428         }
 429
 430         return 0;
 431
 432 error_disable_reg:
 433         if (!IS_ERR(st->vref_reg))
 434                 regulator_disable(st->vref_reg);
 435 error_free_reg:
 436         kfree(indio_dev->channels);
 437
 438         return ret;
 439 }
 440
 441 static int ad5380_remove(struct device *dev)
 442 {
 443         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 444         struct ad5380_state *st = iio_priv(indio_dev);
 445
 446         iio_device_unregister(indio_dev);
 447
 448         kfree(indio_dev->channels);
 449
 450         if (!IS_ERR(st->vref_reg)) {
 451                 regulator_disable(st->vref_reg);
 452         }
 453
 454         return 0;
 455 }
 456
 457 static bool ad5380_reg_false(struct device *dev, unsigned int reg)
 458 {
 459         return false;
 460 }
 461
 462 static const struct regmap_config ad5380_regmap_config = {
 463         .reg_bits = 10,
 464         .val_bits = 14,
 465
 466         .max_register = AD5380_REG_DATA(40),
 467         .cache_type = REGCACHE_RBTREE,
 468
 469         .volatile_reg = ad5380_reg_false,
 470         .readable_reg = ad5380_reg_false,
 471 };
 472
 473 #if IS_ENABLED(CONFIG_SPI_MASTER)
 474
 475 static int ad5380_spi_probe(struct spi_device *spi)
 476 {
 477         const struct spi_device_id *id = spi_get_device_id(spi);
 478         struct regmap *regmap;
 479
 480         regmap = devm_regmap_init_spi(spi, &ad5380_regmap_config);
 481
 482         if (IS_ERR(regmap))
 483                 return PTR_ERR(regmap);
 484
 485         return ad5380_probe(&spi->dev, regmap, id->driver_data, id->name);
 486 }
 487
 488 static int ad5380_spi_remove(struct spi_device *spi)
 489 {
 490         return ad5380_remove(&spi->dev);
 491 }
 492
 493 static const struct spi_device_id ad5380_spi_ids[] = {
 494         { "ad5380-3", ID_AD5380_3 },
 495         { "ad5380-5", ID_AD5380_5 },
 496         { "ad5381-3", ID_AD5381_3 },
 497         { "ad5381-5", ID_AD5381_5 },
 498         { "ad5382-3", ID_AD5382_3 },
 499         { "ad5382-5", ID_AD5382_5 },
 500         { "ad5383-3", ID_AD5383_3 },
 501         { "ad5383-5", ID_AD5383_5 },
 502         { "ad5384-3", ID_AD5380_3 },
 503         { "ad5384-5", ID_AD5380_5 },
 504         { "ad5390-3", ID_AD5390_3 },
 505         { "ad5390-5", ID_AD5390_5 },
 506         { "ad5391-3", ID_AD5391_3 },
 507         { "ad5391-5", ID_AD5391_5 },
 508         { "ad5392-3", ID_AD5392_3 },
 509         { "ad5392-5", ID_AD5392_5 },
 510         { }
 511 };
 512 MODULE_DEVICE_TABLE(spi, ad5380_spi_ids);
 513
 514 static struct spi_driver ad5380_spi_driver = {
 515         .driver = {
 516                    .name = "ad5380",
 517                    .owner = THIS_MODULE,
 518         },
 519         .probe = ad5380_spi_probe,
 520         .remove = ad5380_spi_remove,
 521         .id_table = ad5380_spi_ids,
 522 };
 523
 524 static inline int ad5380_spi_register_driver(void)
 525 {
 526         return spi_register_driver(&ad5380_spi_driver);
 527 }
 528
 529 static inline void ad5380_spi_unregister_driver(void)
 530 {
 531         spi_unregister_driver(&ad5380_spi_driver);
 532 }
 533
 534 #else
 535
 536 static inline int ad5380_spi_register_driver(void)
 537 {
 538         return 0;
 539 }
 540
 541 static inline void ad5380_spi_unregister_driver(void)
 542 {
 543 }
 544
 545 #endif
 546
 547 #if IS_ENABLED(CONFIG_I2C)
 548
 549 static int ad5380_i2c_probe(struct i2c_client *i2c,
 550                             const struct i2c_device_id *id)
 551 {
 552         struct regmap *regmap;
 553
 554         regmap = devm_regmap_init_i2c(i2c, &ad5380_regmap_config);
 555
 556         if (IS_ERR(regmap))
 557                 return PTR_ERR(regmap);
 558
 559         return ad5380_probe(&i2c->dev, regmap, id->driver_data, id->name);
 560 }
 561
 562 static int ad5380_i2c_remove(struct i2c_client *i2c)
 563 {
 564         return ad5380_remove(&i2c->dev);
 565 }
 566
 567 static const struct i2c_device_id ad5380_i2c_ids[] = {
 568         { "ad5380-3", ID_AD5380_3 },
 569         { "ad5380-5", ID_AD5380_5 },
 570         { "ad5381-3", ID_AD5381_3 },
 571         { "ad5381-5", ID_AD5381_5 },
 572         { "ad5382-3", ID_AD5382_3 },
 573         { "ad5382-5", ID_AD5382_5 },
 574         { "ad5383-3", ID_AD5383_3 },
 575         { "ad5383-5", ID_AD5383_5 },
 576         { "ad5384-3", ID_AD5380_3 },
 577         { "ad5384-5", ID_AD5380_5 },
 578         { "ad5390-3", ID_AD5390_3 },
 579         { "ad5390-5", ID_AD5390_5 },
 580         { "ad5391-3", ID_AD5391_3 },
 581         { "ad5391-5", ID_AD5391_5 },
 582         { "ad5392-3", ID_AD5392_3 },
 583         { "ad5392-5", ID_AD5392_5 },
 584         { }
 585 };
 586 MODULE_DEVICE_TABLE(i2c, ad5380_i2c_ids);
 587
 588 static struct i2c_driver ad5380_i2c_driver = {
 589         .driver = {
 590                    .name = "ad5380",
 591                    .owner = THIS_MODULE,
 592         },
 593         .probe = ad5380_i2c_probe,
 594         .remove = ad5380_i2c_remove,
 595         .id_table = ad5380_i2c_ids,
 596 };
 597
 598 static inline int ad5380_i2c_register_driver(void)
 599 {
 600         return i2c_add_driver(&ad5380_i2c_driver);
 601 }
 602
 603 static inline void ad5380_i2c_unregister_driver(void)
 604 {
 605         i2c_del_driver(&ad5380_i2c_driver);
 606 }
 607
 608 #else
 609
 610 static inline int ad5380_i2c_register_driver(void)
 611 {
 612         return 0;
 613 }
 614
 615 static inline void ad5380_i2c_unregister_driver(void)
 616 {
 617 }
 618
 619 #endif
 620
 621 static int __init ad5380_spi_init(void)
 622 {
 623         int ret;
 624
 625         ret = ad5380_spi_register_driver();
 626         if (ret)
 627                 return ret;
 628
 629         ret = ad5380_i2c_register_driver();
 630         if (ret) {
 631                 ad5380_spi_unregister_driver();
 632                 return ret;
 633         }
 634
 635         return 0;
 636 }
 637 module_init(ad5380_spi_init);
 638
 639 static void __exit ad5380_spi_exit(void)
 640 {
 641         ad5380_i2c_unregister_driver();
 642         ad5380_spi_unregister_driver();
 643
 644 }
 645 module_exit(ad5380_spi_exit);
 646
 647 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
 648 MODULE_DESCRIPTION("Analog Devices AD5380/81/82/83/84/90/91/92 DAC");
 649 MODULE_LICENSE("GPL v2");