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 struct ad5380_chip_info {
  41         struct iio_chan_spec    channel_template;
  42         unsigned int            num_channels;
  43         unsigned int            int_vref;
  44 };
  45
  46 /**
  47  * struct ad5380_state - driver instance specific data
  48  * @regmap:             regmap instance used by the device
  49  * @chip_info:          chip model specific constants, available modes etc
  50  * @vref_reg:           vref supply regulator
  51  * @vref:               actual reference voltage used in uA
  52  * @pwr_down:           whether the chip is currently in power down mode
  53  * @lock:               lock to protect the data buffer during regmap ops
  54  */
  55 struct ad5380_state {
  56         struct regmap                   *regmap;
  57         const struct ad5380_chip_info   *chip_info;
  58         struct regulator                *vref_reg;
  59         int                             vref;
  60         bool                            pwr_down;
  61         struct mutex                    lock;
  62 };
  63
  64 enum ad5380_type {
  65         ID_AD5380_3,
  66         ID_AD5380_5,
  67         ID_AD5381_3,
  68         ID_AD5381_5,
  69         ID_AD5382_3,
  70         ID_AD5382_5,
  71         ID_AD5383_3,
  72         ID_AD5383_5,
  73         ID_AD5390_3,
  74         ID_AD5390_5,
  75         ID_AD5391_3,
  76         ID_AD5391_5,
  77         ID_AD5392_3,
  78         ID_AD5392_5,
  79 };
  80
  81 static ssize_t ad5380_read_dac_powerdown(struct iio_dev *indio_dev,
  82         uintptr_t private, const struct iio_chan_spec *chan, char *buf)
  83 {
  84         struct ad5380_state *st = iio_priv(indio_dev);
  85
  86         return sysfs_emit(buf, "%d\n", st->pwr_down);
  87 }
  88
  89 static ssize_t ad5380_write_dac_powerdown(struct iio_dev *indio_dev,
  90          uintptr_t private, const struct iio_chan_spec *chan, const char *buf,
  91          size_t len)
  92 {
  93         struct ad5380_state *st = iio_priv(indio_dev);
  94         bool pwr_down;
  95         int ret;
  96
  97         ret = kstrtobool(buf, &pwr_down);
  98         if (ret)
  99                 return ret;
 100
 101         mutex_lock(&st->lock);
 102
 103         if (pwr_down)
 104                 ret = regmap_write(st->regmap, AD5380_REG_SF_PWR_DOWN, 0);
 105         else
 106                 ret = regmap_write(st->regmap, AD5380_REG_SF_PWR_UP, 0);
 107
 108         st->pwr_down = pwr_down;
 109
 110         mutex_unlock(&st->lock);
 111
 112         return ret ? ret : len;
 113 }
 114
 115 static const char * const ad5380_powerdown_modes[] = {
 116         "100kohm_to_gnd",
 117         "three_state",
 118 };
 119
 120 static int ad5380_get_powerdown_mode(struct iio_dev *indio_dev,
 121         const struct iio_chan_spec *chan)
 122 {
 123         struct ad5380_state *st = iio_priv(indio_dev);
 124         unsigned int mode;
 125         int ret;
 126
 127         ret = regmap_read(st->regmap, AD5380_REG_SF_CTRL, &mode);
 128         if (ret)
 129                 return ret;
 130
 131         mode = (mode >> AD5380_CTRL_PWR_DOWN_MODE_OFFSET) & 1;
 132
 133         return mode;
 134 }
 135
 136 static int ad5380_set_powerdown_mode(struct iio_dev *indio_dev,
 137         const struct iio_chan_spec *chan, unsigned int mode)
 138 {
 139         struct ad5380_state *st = iio_priv(indio_dev);
 140         int ret;
 141
 142         ret = regmap_update_bits(st->regmap, AD5380_REG_SF_CTRL,
 143                 1 << AD5380_CTRL_PWR_DOWN_MODE_OFFSET,
 144                 mode << AD5380_CTRL_PWR_DOWN_MODE_OFFSET);
 145
 146         return ret;
 147 }
 148
 149 static const struct iio_enum ad5380_powerdown_mode_enum = {
 150         .items = ad5380_powerdown_modes,
 151         .num_items = ARRAY_SIZE(ad5380_powerdown_modes),
 152         .get = ad5380_get_powerdown_mode,
 153         .set = ad5380_set_powerdown_mode,
 154 };
 155
 156 static unsigned int ad5380_info_to_reg(struct iio_chan_spec const *chan,
 157         long info)
 158 {
 159         switch (info) {
 160         case IIO_CHAN_INFO_RAW:
 161                 return AD5380_REG_DATA(chan->address);
 162         case IIO_CHAN_INFO_CALIBBIAS:
 163                 return AD5380_REG_OFFSET(chan->address);
 164         case IIO_CHAN_INFO_CALIBSCALE:
 165                 return AD5380_REG_GAIN(chan->address);
 166         default:
 167                 break;
 168         }
 169
 170         return 0;
 171 }
 172
 173 static int ad5380_write_raw(struct iio_dev *indio_dev,
 174         struct iio_chan_spec const *chan, int val, int val2, long info)
 175 {
 176         const unsigned int max_val = (1 << chan->scan_type.realbits);
 177         struct ad5380_state *st = iio_priv(indio_dev);
 178
 179         switch (info) {
 180         case IIO_CHAN_INFO_RAW:
 181         case IIO_CHAN_INFO_CALIBSCALE:
 182                 if (val >= max_val || val < 0)
 183                         return -EINVAL;
 184
 185                 return regmap_write(st->regmap,
 186                         ad5380_info_to_reg(chan, info),
 187                         val << chan->scan_type.shift);
 188         case IIO_CHAN_INFO_CALIBBIAS:
 189                 val += (1 << chan->scan_type.realbits) / 2;
 190                 if (val >= max_val || val < 0)
 191                         return -EINVAL;
 192
 193                 return regmap_write(st->regmap,
 194                         AD5380_REG_OFFSET(chan->address),
 195                         val << chan->scan_type.shift);
 196         default:
 197                 break;
 198         }
 199         return -EINVAL;
 200 }
 201
 202 static int ad5380_read_raw(struct iio_dev *indio_dev,
 203         struct iio_chan_spec const *chan, int *val, int *val2, long info)
 204 {
 205         struct ad5380_state *st = iio_priv(indio_dev);
 206         int ret;
 207
 208         switch (info) {
 209         case IIO_CHAN_INFO_RAW:
 210         case IIO_CHAN_INFO_CALIBSCALE:
 211                 ret = regmap_read(st->regmap, ad5380_info_to_reg(chan, info),
 212                                         val);
 213                 if (ret)
 214                         return ret;
 215                 *val >>= chan->scan_type.shift;
 216                 return IIO_VAL_INT;
 217         case IIO_CHAN_INFO_CALIBBIAS:
 218                 ret = regmap_read(st->regmap, AD5380_REG_OFFSET(chan->address),
 219                                         val);
 220                 if (ret)
 221                         return ret;
 222                 *val >>= chan->scan_type.shift;
 223                 *val -= (1 << chan->scan_type.realbits) / 2;
 224                 return IIO_VAL_INT;
 225         case IIO_CHAN_INFO_SCALE:
 226                 *val = 2 * st->vref;
 227                 *val2 = chan->scan_type.realbits;
 228                 return IIO_VAL_FRACTIONAL_LOG2;
 229         default:
 230                 break;
 231         }
 232
 233         return -EINVAL;
 234 }
 235
 236 static const struct iio_info ad5380_info = {
 237         .read_raw = ad5380_read_raw,
 238         .write_raw = ad5380_write_raw,
 239 };
 240
 241 static const struct iio_chan_spec_ext_info ad5380_ext_info[] = {
 242         {
 243                 .name = "powerdown",
 244                 .read = ad5380_read_dac_powerdown,
 245                 .write = ad5380_write_dac_powerdown,
 246                 .shared = IIO_SEPARATE,
 247         },
 248         IIO_ENUM("powerdown_mode", IIO_SHARED_BY_TYPE,
 249                  &ad5380_powerdown_mode_enum),
 250         IIO_ENUM_AVAILABLE("powerdown_mode", IIO_SHARED_BY_TYPE, &ad5380_powerdown_mode_enum),
 251         { },
 252 };
 253
 254 #define AD5380_CHANNEL(_bits) {                                 \
 255         .type = IIO_VOLTAGE,                                    \
 256         .indexed = 1,                                           \
 257         .output = 1,                                            \
 258         .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |          \
 259                 BIT(IIO_CHAN_INFO_CALIBSCALE) |                 \
 260                 BIT(IIO_CHAN_INFO_CALIBBIAS),                   \
 261         .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),   \
 262         .scan_type = {                                          \
 263                 .sign = 'u',                                    \
 264                 .realbits = (_bits),                            \
 265                 .storagebits =  16,                             \
 266                 .shift = 14 - (_bits),                          \
 267         },                                                      \
 268         .ext_info = ad5380_ext_info,                            \
 269 }
 270
 271 static const struct ad5380_chip_info ad5380_chip_info_tbl[] = {
 272         [ID_AD5380_3] = {
 273                 .channel_template = AD5380_CHANNEL(14),
 274                 .num_channels = 40,
 275                 .int_vref = 1250,
 276         },
 277         [ID_AD5380_5] = {
 278                 .channel_template = AD5380_CHANNEL(14),
 279                 .num_channels = 40,
 280                 .int_vref = 2500,
 281         },
 282         [ID_AD5381_3] = {
 283                 .channel_template = AD5380_CHANNEL(12),
 284                 .num_channels = 16,
 285                 .int_vref = 1250,
 286         },
 287         [ID_AD5381_5] = {
 288                 .channel_template = AD5380_CHANNEL(12),
 289                 .num_channels = 16,
 290                 .int_vref = 2500,
 291         },
 292         [ID_AD5382_3] = {
 293                 .channel_template = AD5380_CHANNEL(14),
 294                 .num_channels = 32,
 295                 .int_vref = 1250,
 296         },
 297         [ID_AD5382_5] = {
 298                 .channel_template = AD5380_CHANNEL(14),
 299                 .num_channels = 32,
 300                 .int_vref = 2500,
 301         },
 302         [ID_AD5383_3] = {
 303                 .channel_template = AD5380_CHANNEL(12),
 304                 .num_channels = 32,
 305                 .int_vref = 1250,
 306         },
 307         [ID_AD5383_5] = {
 308                 .channel_template = AD5380_CHANNEL(12),
 309                 .num_channels = 32,
 310                 .int_vref = 2500,
 311         },
 312         [ID_AD5390_3] = {
 313                 .channel_template = AD5380_CHANNEL(14),
 314                 .num_channels = 16,
 315                 .int_vref = 1250,
 316         },
 317         [ID_AD5390_5] = {
 318                 .channel_template = AD5380_CHANNEL(14),
 319                 .num_channels = 16,
 320                 .int_vref = 2500,
 321         },
 322         [ID_AD5391_3] = {
 323                 .channel_template = AD5380_CHANNEL(12),
 324                 .num_channels = 16,
 325                 .int_vref = 1250,
 326         },
 327         [ID_AD5391_5] = {
 328                 .channel_template = AD5380_CHANNEL(12),
 329                 .num_channels = 16,
 330                 .int_vref = 2500,
 331         },
 332         [ID_AD5392_3] = {
 333                 .channel_template = AD5380_CHANNEL(14),
 334                 .num_channels = 8,
 335                 .int_vref = 1250,
 336         },
 337         [ID_AD5392_5] = {
 338                 .channel_template = AD5380_CHANNEL(14),
 339                 .num_channels = 8,
 340                 .int_vref = 2500,
 341         },
 342 };
 343
 344 static int ad5380_alloc_channels(struct iio_dev *indio_dev)
 345 {
 346         struct ad5380_state *st = iio_priv(indio_dev);
 347         struct iio_chan_spec *channels;
 348         unsigned int i;
 349
 350         channels = kcalloc(st->chip_info->num_channels,
 351                            sizeof(struct iio_chan_spec), GFP_KERNEL);
 352
 353         if (!channels)
 354                 return -ENOMEM;
 355
 356         for (i = 0; i < st->chip_info->num_channels; ++i) {
 357                 channels[i] = st->chip_info->channel_template;
 358                 channels[i].channel = i;
 359                 channels[i].address = i;
 360         }
 361
 362         indio_dev->channels = channels;
 363
 364         return 0;
 365 }
 366
 367 static int ad5380_probe(struct device *dev, struct regmap *regmap,
 368                         enum ad5380_type type, const char *name)
 369 {
 370         struct iio_dev *indio_dev;
 371         struct ad5380_state *st;
 372         unsigned int ctrl = 0;
 373         int ret;
 374
 375         indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
 376         if (indio_dev == NULL) {
 377                 dev_err(dev, "Failed to allocate iio device\n");
 378                 return -ENOMEM;
 379         }
 380
 381         st = iio_priv(indio_dev);
 382         dev_set_drvdata(dev, indio_dev);
 383
 384         st->chip_info = &ad5380_chip_info_tbl[type];
 385         st->regmap = regmap;
 386
 387         indio_dev->name = name;
 388         indio_dev->info = &ad5380_info;
 389         indio_dev->modes = INDIO_DIRECT_MODE;
 390         indio_dev->num_channels = st->chip_info->num_channels;
 391
 392         mutex_init(&st->lock);
 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 void 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 static bool ad5380_reg_false(struct device *dev, unsigned int reg)
 459 {
 460         return false;
 461 }
 462
 463 static const struct regmap_config ad5380_regmap_config = {
 464         .reg_bits = 10,
 465         .val_bits = 14,
 466
 467         .max_register = AD5380_REG_DATA(40),
 468         .cache_type = REGCACHE_RBTREE,
 469
 470         .volatile_reg = ad5380_reg_false,
 471         .readable_reg = ad5380_reg_false,
 472 };
 473
 474 #if IS_ENABLED(CONFIG_SPI_MASTER)
 475
 476 static int ad5380_spi_probe(struct spi_device *spi)
 477 {
 478         const struct spi_device_id *id = spi_get_device_id(spi);
 479         struct regmap *regmap;
 480
 481         regmap = devm_regmap_init_spi(spi, &ad5380_regmap_config);
 482
 483         if (IS_ERR(regmap))
 484                 return PTR_ERR(regmap);
 485
 486         return ad5380_probe(&spi->dev, regmap, id->driver_data, id->name);
 487 }
 488
 489 static void ad5380_spi_remove(struct spi_device *spi)
 490 {
 491         ad5380_remove(&spi->dev);
 492 }
 493
 494 static const struct spi_device_id ad5380_spi_ids[] = {
 495         { "ad5380-3", ID_AD5380_3 },
 496         { "ad5380-5", ID_AD5380_5 },
 497         { "ad5381-3", ID_AD5381_3 },
 498         { "ad5381-5", ID_AD5381_5 },
 499         { "ad5382-3", ID_AD5382_3 },
 500         { "ad5382-5", ID_AD5382_5 },
 501         { "ad5383-3", ID_AD5383_3 },
 502         { "ad5383-5", ID_AD5383_5 },
 503         { "ad5384-3", ID_AD5380_3 },
 504         { "ad5384-5", ID_AD5380_5 },
 505         { "ad5390-3", ID_AD5390_3 },
 506         { "ad5390-5", ID_AD5390_5 },
 507         { "ad5391-3", ID_AD5391_3 },
 508         { "ad5391-5", ID_AD5391_5 },
 509         { "ad5392-3", ID_AD5392_3 },
 510         { "ad5392-5", ID_AD5392_5 },
 511         { }
 512 };
 513 MODULE_DEVICE_TABLE(spi, ad5380_spi_ids);
 514
 515 static struct spi_driver ad5380_spi_driver = {
 516         .driver = {
 517                    .name = "ad5380",
 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 {
 551         const struct i2c_device_id *id = i2c_client_get_device_id(i2c);
 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 void ad5380_i2c_remove(struct i2c_client *i2c)
 563 {
 564         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         },
 592         .probe = ad5380_i2c_probe,
 593         .remove = ad5380_i2c_remove,
 594         .id_table = ad5380_i2c_ids,
 595 };
 596
 597 static inline int ad5380_i2c_register_driver(void)
 598 {
 599         return i2c_add_driver(&ad5380_i2c_driver);
 600 }
 601
 602 static inline void ad5380_i2c_unregister_driver(void)
 603 {
 604         i2c_del_driver(&ad5380_i2c_driver);
 605 }
 606
 607 #else
 608
 609 static inline int ad5380_i2c_register_driver(void)
 610 {
 611         return 0;
 612 }
 613
 614 static inline void ad5380_i2c_unregister_driver(void)
 615 {
 616 }
 617
 618 #endif
 619
 620 static int __init ad5380_spi_init(void)
 621 {
 622         int ret;
 623
 624         ret = ad5380_spi_register_driver();
 625         if (ret)
 626                 return ret;
 627
 628         ret = ad5380_i2c_register_driver();
 629         if (ret) {
 630                 ad5380_spi_unregister_driver();
 631                 return ret;
 632         }
 633
 634         return 0;
 635 }
 636 module_init(ad5380_spi_init);
 637
 638 static void __exit ad5380_spi_exit(void)
 639 {
 640         ad5380_i2c_unregister_driver();
 641         ad5380_spi_unregister_driver();
 642
 643 }
 644 module_exit(ad5380_spi_exit);
 645
 646 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
 647 MODULE_DESCRIPTION("Analog Devices AD5380/81/82/83/84/90/91/92 DAC");
 648 MODULE_LICENSE("GPL v2");