drivers/iio/dac/ad5380.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Analog devices AD5380, AD5381, AD5382, AD5383, AD5390, AD5391, AD5392
   4  * multi-channel Digital to Analog Converters driver
   5  *
   6  * Copyright 2011 Analog Devices Inc.
   7  */
   8
   9 #include <linux/device.h>
  10 #include <linux/err.h>
  11 #include <linux/i2c.h>
  12 #include <linux/kernel.h>
  13 #include <linux/module.h>
  14 #include <linux/spi/spi.h>
  15 #include <linux/slab.h>
  16 #include <linux/sysfs.h>
  17 #include <linux/regmap.h>
  18 #include <linux/regulator/consumer.h>
  19
  20 #include <linux/iio/iio.h>
  21 #include <linux/iio/sysfs.h>
  22
  23 #define AD5380_REG_DATA(x)      (((x) << 2) | 3)
  24 #define AD5380_REG_OFFSET(x)    (((x) << 2) | 2)
  25 #define AD5380_REG_GAIN(x)      (((x) << 2) | 1)
  26 #define AD5380_REG_SF_PWR_DOWN  (8 << 2)
  27 #define AD5380_REG_SF_PWR_UP    (9 << 2)
  28 #define AD5380_REG_SF_CTRL      (12 << 2)
  29
  30 #define AD5380_CTRL_PWR_DOWN_MODE_OFFSET        13
  31 #define AD5380_CTRL_INT_VREF_2V5                BIT(12)
  32 #define AD5380_CTRL_INT_VREF_EN                 BIT(10)
  33
  34 /**
  35  * struct ad5380_chip_info - chip specific information
  36  * @channel_template:   channel specification template
  37  * @num_channels:       number of channels
  38  * @int_vref:           internal vref in uV
  39 */
  40
  41 struct ad5380_chip_info {
  42         struct iio_chan_spec    channel_template;
  43         unsigned int            num_channels;
  44         unsigned int            int_vref;
  45 };
  46
  47 /**
  48  * struct ad5380_state - driver instance specific data
  49  * @regmap:             regmap instance used by the device
  50  * @chip_info:          chip model specific constants, available modes etc
  51  * @vref_reg:           vref supply regulator
  52  * @vref:               actual reference voltage used in uA
  53  * @pwr_down:           whether the chip is currently in power down mode
  54  * @lock:               lock to protect the data buffer during regmap ops
  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         struct mutex                    lock;
  64 };
  65
  66 enum ad5380_type {
  67         ID_AD5380_3,
  68         ID_AD5380_5,
  69         ID_AD5381_3,
  70         ID_AD5381_5,
  71         ID_AD5382_3,
  72         ID_AD5382_5,
  73         ID_AD5383_3,
  74         ID_AD5383_5,
  75         ID_AD5390_3,
  76         ID_AD5390_5,
  77         ID_AD5391_3,
  78         ID_AD5391_5,
  79         ID_AD5392_3,
  80         ID_AD5392_5,
  81 };
  82
  83 static ssize_t ad5380_read_dac_powerdown(struct iio_dev *indio_dev,
  84         uintptr_t private, const struct iio_chan_spec *chan, char *buf)
  85 {
  86         struct ad5380_state *st = iio_priv(indio_dev);
  87
  88         return sprintf(buf, "%d\n", st->pwr_down);
  89 }
  90
  91 static ssize_t ad5380_write_dac_powerdown(struct iio_dev *indio_dev,
  92          uintptr_t private, const struct iio_chan_spec *chan, const char *buf,
  93          size_t len)
  94 {
  95         struct ad5380_state *st = iio_priv(indio_dev);
  96         bool pwr_down;
  97         int ret;
  98
  99         ret = strtobool(buf, &pwr_down);
 100         if (ret)
 101                 return ret;
 102
 103         mutex_lock(&st->lock);
 104
 105         if (pwr_down)
 106                 ret = regmap_write(st->regmap, AD5380_REG_SF_PWR_DOWN, 0);
 107         else
 108                 ret = regmap_write(st->regmap, AD5380_REG_SF_PWR_UP, 0);
 109
 110         st->pwr_down = pwr_down;
 111
 112         mutex_unlock(&st->lock);
 113
 114         return ret ? ret : len;
 115 }
 116
 117 static const char * const ad5380_powerdown_modes[] = {
 118         "100kohm_to_gnd",
 119         "three_state",
 120 };
 121
 122 static int ad5380_get_powerdown_mode(struct iio_dev *indio_dev,
 123         const struct iio_chan_spec *chan)
 124 {
 125         struct ad5380_state *st = iio_priv(indio_dev);
 126         unsigned int mode;
 127         int ret;
 128
 129         ret = regmap_read(st->regmap, AD5380_REG_SF_CTRL, &mode);
 130         if (ret)
 131                 return ret;
 132
 133         mode = (mode >> AD5380_CTRL_PWR_DOWN_MODE_OFFSET) & 1;
 134
 135         return mode;
 136 }
 137
 138 static int ad5380_set_powerdown_mode(struct iio_dev *indio_dev,
 139         const struct iio_chan_spec *chan, unsigned int mode)
 140 {
 141         struct ad5380_state *st = iio_priv(indio_dev);
 142         int ret;
 143
 144         ret = regmap_update_bits(st->regmap, AD5380_REG_SF_CTRL,
 145                 1 << AD5380_CTRL_PWR_DOWN_MODE_OFFSET,
 146                 mode << AD5380_CTRL_PWR_DOWN_MODE_OFFSET);
 147
 148         return ret;
 149 }
 150
 151 static const struct iio_enum ad5380_powerdown_mode_enum = {
 152         .items = ad5380_powerdown_modes,
 153         .num_items = ARRAY_SIZE(ad5380_powerdown_modes),
 154         .get = ad5380_get_powerdown_mode,
 155         .set = ad5380_set_powerdown_mode,
 156 };
 157
 158 static unsigned int ad5380_info_to_reg(struct iio_chan_spec const *chan,
 159         long info)
 160 {
 161         switch (info) {
 162         case IIO_CHAN_INFO_RAW:
 163                 return AD5380_REG_DATA(chan->address);
 164         case IIO_CHAN_INFO_CALIBBIAS:
 165                 return AD5380_REG_OFFSET(chan->address);
 166         case IIO_CHAN_INFO_CALIBSCALE:
 167                 return AD5380_REG_GAIN(chan->address);
 168         default:
 169                 break;
 170         }
 171
 172         return 0;
 173 }
 174
 175 static int ad5380_write_raw(struct iio_dev *indio_dev,
 176         struct iio_chan_spec const *chan, int val, int val2, long info)
 177 {
 178         const unsigned int max_val = (1 << chan->scan_type.realbits);
 179         struct ad5380_state *st = iio_priv(indio_dev);
 180
 181         switch (info) {
 182         case IIO_CHAN_INFO_RAW:
 183         case IIO_CHAN_INFO_CALIBSCALE:
 184                 if (val >= max_val || val < 0)
 185                         return -EINVAL;
 186
 187                 return regmap_write(st->regmap,
 188                         ad5380_info_to_reg(chan, info),
 189                         val << chan->scan_type.shift);
 190         case IIO_CHAN_INFO_CALIBBIAS:
 191                 val += (1 << chan->scan_type.realbits) / 2;
 192                 if (val >= max_val || val < 0)
 193                         return -EINVAL;
 194
 195                 return regmap_write(st->regmap,
 196                         AD5380_REG_OFFSET(chan->address),
 197                         val << chan->scan_type.shift);
 198         default:
 199                 break;
 200         }
 201         return -EINVAL;
 202 }
 203
 204 static int ad5380_read_raw(struct iio_dev *indio_dev,
 205         struct iio_chan_spec const *chan, int *val, int *val2, long info)
 206 {
 207         struct ad5380_state *st = iio_priv(indio_dev);
 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                 *val = 2 * st->vref;
 229                 *val2 = chan->scan_type.realbits;
 230                 return IIO_VAL_FRACTIONAL_LOG2;
 231         default:
 232                 break;
 233         }
 234
 235         return -EINVAL;
 236 }
 237
 238 static const struct iio_info ad5380_info = {
 239         .read_raw = ad5380_read_raw,
 240         .write_raw = ad5380_write_raw,
 241 };
 242
 243 static const struct iio_chan_spec_ext_info ad5380_ext_info[] = {
 244         {
 245                 .name = "powerdown",
 246                 .read = ad5380_read_dac_powerdown,
 247                 .write = ad5380_write_dac_powerdown,
 248                 .shared = IIO_SEPARATE,
 249         },
 250         IIO_ENUM("powerdown_mode", IIO_SHARED_BY_TYPE,
 251                  &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 = {                                          \
 265                 .sign = 'u',                                    \
 266                 .realbits = (_bits),                            \
 267                 .storagebits =  16,                             \
 268                 .shift = 14 - (_bits),                          \
 269         },                                                      \
 270         .ext_info = ad5380_ext_info,                            \
 271 }
 272
 273 static const struct ad5380_chip_info ad5380_chip_info_tbl[] = {
 274         [ID_AD5380_3] = {
 275                 .channel_template = AD5380_CHANNEL(14),
 276                 .num_channels = 40,
 277                 .int_vref = 1250,
 278         },
 279         [ID_AD5380_5] = {
 280                 .channel_template = AD5380_CHANNEL(14),
 281                 .num_channels = 40,
 282                 .int_vref = 2500,
 283         },
 284         [ID_AD5381_3] = {
 285                 .channel_template = AD5380_CHANNEL(12),
 286                 .num_channels = 16,
 287                 .int_vref = 1250,
 288         },
 289         [ID_AD5381_5] = {
 290                 .channel_template = AD5380_CHANNEL(12),
 291                 .num_channels = 16,
 292                 .int_vref = 2500,
 293         },
 294         [ID_AD5382_3] = {
 295                 .channel_template = AD5380_CHANNEL(14),
 296                 .num_channels = 32,
 297                 .int_vref = 1250,
 298         },
 299         [ID_AD5382_5] = {
 300                 .channel_template = AD5380_CHANNEL(14),
 301                 .num_channels = 32,
 302                 .int_vref = 2500,
 303         },
 304         [ID_AD5383_3] = {
 305                 .channel_template = AD5380_CHANNEL(12),
 306                 .num_channels = 32,
 307                 .int_vref = 1250,
 308         },
 309         [ID_AD5383_5] = {
 310                 .channel_template = AD5380_CHANNEL(12),
 311                 .num_channels = 32,
 312                 .int_vref = 2500,
 313         },
 314         [ID_AD5390_3] = {
 315                 .channel_template = AD5380_CHANNEL(14),
 316                 .num_channels = 16,
 317                 .int_vref = 1250,
 318         },
 319         [ID_AD5390_5] = {
 320                 .channel_template = AD5380_CHANNEL(14),
 321                 .num_channels = 16,
 322                 .int_vref = 2500,
 323         },
 324         [ID_AD5391_3] = {
 325                 .channel_template = AD5380_CHANNEL(12),
 326                 .num_channels = 16,
 327                 .int_vref = 1250,
 328         },
 329         [ID_AD5391_5] = {
 330                 .channel_template = AD5380_CHANNEL(12),
 331                 .num_channels = 16,
 332                 .int_vref = 2500,
 333         },
 334         [ID_AD5392_3] = {
 335                 .channel_template = AD5380_CHANNEL(14),
 336                 .num_channels = 8,
 337                 .int_vref = 1250,
 338         },
 339         [ID_AD5392_5] = {
 340                 .channel_template = AD5380_CHANNEL(14),
 341                 .num_channels = 8,
 342                 .int_vref = 2500,
 343         },
 344 };
 345
 346 static int ad5380_alloc_channels(struct iio_dev *indio_dev)
 347 {
 348         struct ad5380_state *st = iio_priv(indio_dev);
 349         struct iio_chan_spec *channels;
 350         unsigned int i;
 351
 352         channels = kcalloc(st->chip_info->num_channels,
 353                            sizeof(struct iio_chan_spec), GFP_KERNEL);
 354
 355         if (!channels)
 356                 return -ENOMEM;
 357
 358         for (i = 0; i < st->chip_info->num_channels; ++i) {
 359                 channels[i] = st->chip_info->channel_template;
 360                 channels[i].channel = i;
 361                 channels[i].address = i;
 362         }
 363
 364         indio_dev->channels = channels;
 365
 366         return 0;
 367 }
 368
 369 static int ad5380_probe(struct device *dev, struct regmap *regmap,
 370                         enum ad5380_type type, const char *name)
 371 {
 372         struct iio_dev *indio_dev;
 373         struct ad5380_state *st;
 374         unsigned int ctrl = 0;
 375         int ret;
 376
 377         indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
 378         if (indio_dev == NULL) {
 379                 dev_err(dev, "Failed to allocate iio device\n");
 380                 return -ENOMEM;
 381         }
 382
 383         st = iio_priv(indio_dev);
 384         dev_set_drvdata(dev, indio_dev);
 385
 386         st->chip_info = &ad5380_chip_info_tbl[type];
 387         st->regmap = regmap;
 388
 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         mutex_init(&st->lock);
 395
 396         ret = ad5380_alloc_channels(indio_dev);
 397         if (ret) {
 398                 dev_err(dev, "Failed to allocate channel spec: %d\n", ret);
 399                 return ret;
 400         }
 401
 402         if (st->chip_info->int_vref == 2500)
 403                 ctrl |= AD5380_CTRL_INT_VREF_2V5;
 404
 405         st->vref_reg = devm_regulator_get(dev, "vref");
 406         if (!IS_ERR(st->vref_reg)) {
 407                 ret = regulator_enable(st->vref_reg);
 408                 if (ret) {
 409                         dev_err(dev, "Failed to enable vref regulators: %d\n",
 410                                 ret);
 411                         goto error_free_reg;
 412                 }
 413
 414                 ret = regulator_get_voltage(st->vref_reg);
 415                 if (ret < 0)
 416                         goto error_disable_reg;
 417
 418                 st->vref = ret / 1000;
 419         } else {
 420                 st->vref = st->chip_info->int_vref;
 421                 ctrl |= AD5380_CTRL_INT_VREF_EN;
 422         }
 423
 424         ret = regmap_write(st->regmap, AD5380_REG_SF_CTRL, ctrl);
 425         if (ret) {
 426                 dev_err(dev, "Failed to write to device: %d\n", ret);
 427                 goto error_disable_reg;
 428         }
 429
 430         ret = iio_device_register(indio_dev);
 431         if (ret) {
 432                 dev_err(dev, "Failed to register iio device: %d\n", ret);
 433                 goto error_disable_reg;
 434         }
 435
 436         return 0;
 437
 438 error_disable_reg:
 439         if (!IS_ERR(st->vref_reg))
 440                 regulator_disable(st->vref_reg);
 441 error_free_reg:
 442         kfree(indio_dev->channels);
 443
 444         return ret;
 445 }
 446
 447 static int ad5380_remove(struct device *dev)
 448 {
 449         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 450         struct ad5380_state *st = iio_priv(indio_dev);
 451
 452         iio_device_unregister(indio_dev);
 453
 454         kfree(indio_dev->channels);
 455
 456         if (!IS_ERR(st->vref_reg)) {
 457                 regulator_disable(st->vref_reg);
 458         }
 459
 460         return 0;
 461 }
 462
 463 static bool ad5380_reg_false(struct device *dev, unsigned int reg)
 464 {
 465         return false;
 466 }
 467
 468 static const struct regmap_config ad5380_regmap_config = {
 469         .reg_bits = 10,
 470         .val_bits = 14,
 471
 472         .max_register = AD5380_REG_DATA(40),
 473         .cache_type = REGCACHE_RBTREE,
 474
 475         .volatile_reg = ad5380_reg_false,
 476         .readable_reg = ad5380_reg_false,
 477 };
 478
 479 #if IS_ENABLED(CONFIG_SPI_MASTER)
 480
 481 static int ad5380_spi_probe(struct spi_device *spi)
 482 {
 483         const struct spi_device_id *id = spi_get_device_id(spi);
 484         struct regmap *regmap;
 485
 486         regmap = devm_regmap_init_spi(spi, &ad5380_regmap_config);
 487
 488         if (IS_ERR(regmap))
 489                 return PTR_ERR(regmap);
 490
 491         return ad5380_probe(&spi->dev, regmap, id->driver_data, id->name);
 492 }
 493
 494 static int ad5380_spi_remove(struct spi_device *spi)
 495 {
 496         return ad5380_remove(&spi->dev);
 497 }
 498
 499 static const struct spi_device_id ad5380_spi_ids[] = {
 500         { "ad5380-3", ID_AD5380_3 },
 501         { "ad5380-5", ID_AD5380_5 },
 502         { "ad5381-3", ID_AD5381_3 },
 503         { "ad5381-5", ID_AD5381_5 },
 504         { "ad5382-3", ID_AD5382_3 },
 505         { "ad5382-5", ID_AD5382_5 },
 506         { "ad5383-3", ID_AD5383_3 },
 507         { "ad5383-5", ID_AD5383_5 },
 508         { "ad5384-3", ID_AD5380_3 },
 509         { "ad5384-5", ID_AD5380_5 },
 510         { "ad5390-3", ID_AD5390_3 },
 511         { "ad5390-5", ID_AD5390_5 },
 512         { "ad5391-3", ID_AD5391_3 },
 513         { "ad5391-5", ID_AD5391_5 },
 514         { "ad5392-3", ID_AD5392_3 },
 515         { "ad5392-5", ID_AD5392_5 },
 516         { }
 517 };
 518 MODULE_DEVICE_TABLE(spi, ad5380_spi_ids);
 519
 520 static struct spi_driver ad5380_spi_driver = {
 521         .driver = {
 522                    .name = "ad5380",
 523         },
 524         .probe = ad5380_spi_probe,
 525         .remove = ad5380_spi_remove,
 526         .id_table = ad5380_spi_ids,
 527 };
 528
 529 static inline int ad5380_spi_register_driver(void)
 530 {
 531         return spi_register_driver(&ad5380_spi_driver);
 532 }
 533
 534 static inline void ad5380_spi_unregister_driver(void)
 535 {
 536         spi_unregister_driver(&ad5380_spi_driver);
 537 }
 538
 539 #else
 540
 541 static inline int ad5380_spi_register_driver(void)
 542 {
 543         return 0;
 544 }
 545
 546 static inline void ad5380_spi_unregister_driver(void)
 547 {
 548 }
 549
 550 #endif
 551
 552 #if IS_ENABLED(CONFIG_I2C)
 553
 554 static int ad5380_i2c_probe(struct i2c_client *i2c,
 555                             const struct i2c_device_id *id)
 556 {
 557         struct regmap *regmap;
 558
 559         regmap = devm_regmap_init_i2c(i2c, &ad5380_regmap_config);
 560
 561         if (IS_ERR(regmap))
 562                 return PTR_ERR(regmap);
 563
 564         return ad5380_probe(&i2c->dev, regmap, id->driver_data, id->name);
 565 }
 566
 567 static int ad5380_i2c_remove(struct i2c_client *i2c)
 568 {
 569         return ad5380_remove(&i2c->dev);
 570 }
 571
 572 static const struct i2c_device_id ad5380_i2c_ids[] = {
 573         { "ad5380-3", ID_AD5380_3 },
 574         { "ad5380-5", ID_AD5380_5 },
 575         { "ad5381-3", ID_AD5381_3 },
 576         { "ad5381-5", ID_AD5381_5 },
 577         { "ad5382-3", ID_AD5382_3 },
 578         { "ad5382-5", ID_AD5382_5 },
 579         { "ad5383-3", ID_AD5383_3 },
 580         { "ad5383-5", ID_AD5383_5 },
 581         { "ad5384-3", ID_AD5380_3 },
 582         { "ad5384-5", ID_AD5380_5 },
 583         { "ad5390-3", ID_AD5390_3 },
 584         { "ad5390-5", ID_AD5390_5 },
 585         { "ad5391-3", ID_AD5391_3 },
 586         { "ad5391-5", ID_AD5391_5 },
 587         { "ad5392-3", ID_AD5392_3 },
 588         { "ad5392-5", ID_AD5392_5 },
 589         { }
 590 };
 591 MODULE_DEVICE_TABLE(i2c, ad5380_i2c_ids);
 592
 593 static struct i2c_driver ad5380_i2c_driver = {
 594         .driver = {
 595                    .name = "ad5380",
 596         },
 597         .probe = ad5380_i2c_probe,
 598         .remove = ad5380_i2c_remove,
 599         .id_table = ad5380_i2c_ids,
 600 };
 601
 602 static inline int ad5380_i2c_register_driver(void)
 603 {
 604         return i2c_add_driver(&ad5380_i2c_driver);
 605 }
 606
 607 static inline void ad5380_i2c_unregister_driver(void)
 608 {
 609         i2c_del_driver(&ad5380_i2c_driver);
 610 }
 611
 612 #else
 613
 614 static inline int ad5380_i2c_register_driver(void)
 615 {
 616         return 0;
 617 }
 618
 619 static inline void ad5380_i2c_unregister_driver(void)
 620 {
 621 }
 622
 623 #endif
 624
 625 static int __init ad5380_spi_init(void)
 626 {
 627         int ret;
 628
 629         ret = ad5380_spi_register_driver();
 630         if (ret)
 631                 return ret;
 632
 633         ret = ad5380_i2c_register_driver();
 634         if (ret) {
 635                 ad5380_spi_unregister_driver();
 636                 return ret;
 637         }
 638
 639         return 0;
 640 }
 641 module_init(ad5380_spi_init);
 642
 643 static void __exit ad5380_spi_exit(void)
 644 {
 645         ad5380_i2c_unregister_driver();
 646         ad5380_spi_unregister_driver();
 647
 648 }
 649 module_exit(ad5380_spi_exit);
 650
 651 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
 652 MODULE_DESCRIPTION("Analog Devices AD5380/81/82/83/84/90/91/92 DAC");
 653 MODULE_LICENSE("GPL v2");