drivers/iio/dac/ad5446.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * AD5446 SPI DAC driver
   4  *
   5  * Copyright 2010 Analog Devices Inc.
   6  */
   7
   8 #include <linux/interrupt.h>
   9 #include <linux/workqueue.h>
  10 #include <linux/device.h>
  11 #include <linux/kernel.h>
  12 #include <linux/slab.h>
  13 #include <linux/sysfs.h>
  14 #include <linux/list.h>
  15 #include <linux/spi/spi.h>
  16 #include <linux/i2c.h>
  17 #include <linux/regulator/consumer.h>
  18 #include <linux/err.h>
  19 #include <linux/module.h>
  20 #include <linux/mod_devicetable.h>
  21
  22 #include <linux/iio/iio.h>
  23 #include <linux/iio/sysfs.h>
  24
  25 #include <asm/unaligned.h>
  26
  27 #define MODE_PWRDWN_1k          0x1
  28 #define MODE_PWRDWN_100k        0x2
  29 #define MODE_PWRDWN_TRISTATE    0x3
  30
  31 /**
  32  * struct ad5446_state - driver instance specific data
  33  * @dev:                this device
  34  * @chip_info:          chip model specific constants, available modes etc
  35  * @reg:                supply regulator
  36  * @vref_mv:            actual reference voltage used
  37  * @cached_val:         store/retrieve values during power down
  38  * @pwr_down_mode:      power down mode (1k, 100k or tristate)
  39  * @pwr_down:           true if the device is in power down
  40  * @lock:               lock to protect the data buffer during write ops
  41  */
  42
  43 struct ad5446_state {
  44         struct device           *dev;
  45         const struct ad5446_chip_info   *chip_info;
  46         struct regulator                *reg;
  47         unsigned short                  vref_mv;
  48         unsigned                        cached_val;
  49         unsigned                        pwr_down_mode;
  50         unsigned                        pwr_down;
  51         struct mutex                    lock;
  52 };
  53
  54 /**
  55  * struct ad5446_chip_info - chip specific information
  56  * @channel:            channel spec for the DAC
  57  * @int_vref_mv:        AD5620/40/60: the internal reference voltage
  58  * @write:              chip specific helper function to write to the register
  59  */
  60
  61 struct ad5446_chip_info {
  62         struct iio_chan_spec    channel;
  63         u16                     int_vref_mv;
  64         int                     (*write)(struct ad5446_state *st, unsigned val);
  65 };
  66
  67 static const char * const ad5446_powerdown_modes[] = {
  68         "1kohm_to_gnd", "100kohm_to_gnd", "three_state"
  69 };
  70
  71 static int ad5446_set_powerdown_mode(struct iio_dev *indio_dev,
  72         const struct iio_chan_spec *chan, unsigned int mode)
  73 {
  74         struct ad5446_state *st = iio_priv(indio_dev);
  75
  76         st->pwr_down_mode = mode + 1;
  77
  78         return 0;
  79 }
  80
  81 static int ad5446_get_powerdown_mode(struct iio_dev *indio_dev,
  82         const struct iio_chan_spec *chan)
  83 {
  84         struct ad5446_state *st = iio_priv(indio_dev);
  85
  86         return st->pwr_down_mode - 1;
  87 }
  88
  89 static const struct iio_enum ad5446_powerdown_mode_enum = {
  90         .items = ad5446_powerdown_modes,
  91         .num_items = ARRAY_SIZE(ad5446_powerdown_modes),
  92         .get = ad5446_get_powerdown_mode,
  93         .set = ad5446_set_powerdown_mode,
  94 };
  95
  96 static ssize_t ad5446_read_dac_powerdown(struct iio_dev *indio_dev,
  97                                            uintptr_t private,
  98                                            const struct iio_chan_spec *chan,
  99                                            char *buf)
 100 {
 101         struct ad5446_state *st = iio_priv(indio_dev);
 102
 103         return sprintf(buf, "%d\n", st->pwr_down);
 104 }
 105
 106 static ssize_t ad5446_write_dac_powerdown(struct iio_dev *indio_dev,
 107                                             uintptr_t private,
 108                                             const struct iio_chan_spec *chan,
 109                                             const char *buf, size_t len)
 110 {
 111         struct ad5446_state *st = iio_priv(indio_dev);
 112         unsigned int shift;
 113         unsigned int val;
 114         bool powerdown;
 115         int ret;
 116
 117         ret = strtobool(buf, &powerdown);
 118         if (ret)
 119                 return ret;
 120
 121         mutex_lock(&st->lock);
 122         st->pwr_down = powerdown;
 123
 124         if (st->pwr_down) {
 125                 shift = chan->scan_type.realbits + chan->scan_type.shift;
 126                 val = st->pwr_down_mode << shift;
 127         } else {
 128                 val = st->cached_val;
 129         }
 130
 131         ret = st->chip_info->write(st, val);
 132         mutex_unlock(&st->lock);
 133
 134         return ret ? ret : len;
 135 }
 136
 137 static const struct iio_chan_spec_ext_info ad5446_ext_info_powerdown[] = {
 138         {
 139                 .name = "powerdown",
 140                 .read = ad5446_read_dac_powerdown,
 141                 .write = ad5446_write_dac_powerdown,
 142                 .shared = IIO_SEPARATE,
 143         },
 144         IIO_ENUM("powerdown_mode", IIO_SEPARATE, &ad5446_powerdown_mode_enum),
 145         IIO_ENUM_AVAILABLE("powerdown_mode", &ad5446_powerdown_mode_enum),
 146         { },
 147 };
 148
 149 #define _AD5446_CHANNEL(bits, storage, _shift, ext) { \
 150         .type = IIO_VOLTAGE, \
 151         .indexed = 1, \
 152         .output = 1, \
 153         .channel = 0, \
 154         .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
 155         .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
 156         .scan_type = { \
 157                 .sign = 'u', \
 158                 .realbits = (bits), \
 159                 .storagebits = (storage), \
 160                 .shift = (_shift), \
 161                 }, \
 162         .ext_info = (ext), \
 163 }
 164
 165 #define AD5446_CHANNEL(bits, storage, shift) \
 166         _AD5446_CHANNEL(bits, storage, shift, NULL)
 167
 168 #define AD5446_CHANNEL_POWERDOWN(bits, storage, shift) \
 169         _AD5446_CHANNEL(bits, storage, shift, ad5446_ext_info_powerdown)
 170
 171 static int ad5446_read_raw(struct iio_dev *indio_dev,
 172                            struct iio_chan_spec const *chan,
 173                            int *val,
 174                            int *val2,
 175                            long m)
 176 {
 177         struct ad5446_state *st = iio_priv(indio_dev);
 178
 179         switch (m) {
 180         case IIO_CHAN_INFO_RAW:
 181                 *val = st->cached_val;
 182                 return IIO_VAL_INT;
 183         case IIO_CHAN_INFO_SCALE:
 184                 *val = st->vref_mv;
 185                 *val2 = chan->scan_type.realbits;
 186                 return IIO_VAL_FRACTIONAL_LOG2;
 187         }
 188         return -EINVAL;
 189 }
 190
 191 static int ad5446_write_raw(struct iio_dev *indio_dev,
 192                                struct iio_chan_spec const *chan,
 193                                int val,
 194                                int val2,
 195                                long mask)
 196 {
 197         struct ad5446_state *st = iio_priv(indio_dev);
 198         int ret = 0;
 199
 200         switch (mask) {
 201         case IIO_CHAN_INFO_RAW:
 202                 if (val >= (1 << chan->scan_type.realbits) || val < 0)
 203                         return -EINVAL;
 204
 205                 val <<= chan->scan_type.shift;
 206                 mutex_lock(&st->lock);
 207                 st->cached_val = val;
 208                 if (!st->pwr_down)
 209                         ret = st->chip_info->write(st, val);
 210                 mutex_unlock(&st->lock);
 211                 break;
 212         default:
 213                 ret = -EINVAL;
 214         }
 215
 216         return ret;
 217 }
 218
 219 static const struct iio_info ad5446_info = {
 220         .read_raw = ad5446_read_raw,
 221         .write_raw = ad5446_write_raw,
 222 };
 223
 224 static int ad5446_probe(struct device *dev, const char *name,
 225                         const struct ad5446_chip_info *chip_info)
 226 {
 227         struct ad5446_state *st;
 228         struct iio_dev *indio_dev;
 229         struct regulator *reg;
 230         int ret, voltage_uv = 0;
 231
 232         reg = devm_regulator_get(dev, "vcc");
 233         if (!IS_ERR(reg)) {
 234                 ret = regulator_enable(reg);
 235                 if (ret)
 236                         return ret;
 237
 238                 ret = regulator_get_voltage(reg);
 239                 if (ret < 0)
 240                         goto error_disable_reg;
 241
 242                 voltage_uv = ret;
 243         }
 244
 245         indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
 246         if (indio_dev == NULL) {
 247                 ret = -ENOMEM;
 248                 goto error_disable_reg;
 249         }
 250         st = iio_priv(indio_dev);
 251         st->chip_info = chip_info;
 252
 253         dev_set_drvdata(dev, indio_dev);
 254         st->reg = reg;
 255         st->dev = dev;
 256
 257         indio_dev->name = name;
 258         indio_dev->info = &ad5446_info;
 259         indio_dev->modes = INDIO_DIRECT_MODE;
 260         indio_dev->channels = &st->chip_info->channel;
 261         indio_dev->num_channels = 1;
 262
 263         mutex_init(&st->lock);
 264
 265         st->pwr_down_mode = MODE_PWRDWN_1k;
 266
 267         if (st->chip_info->int_vref_mv)
 268                 st->vref_mv = st->chip_info->int_vref_mv;
 269         else if (voltage_uv)
 270                 st->vref_mv = voltage_uv / 1000;
 271         else
 272                 dev_warn(dev, "reference voltage unspecified\n");
 273
 274         ret = iio_device_register(indio_dev);
 275         if (ret)
 276                 goto error_disable_reg;
 277
 278         return 0;
 279
 280 error_disable_reg:
 281         if (!IS_ERR(reg))
 282                 regulator_disable(reg);
 283         return ret;
 284 }
 285
 286 static int ad5446_remove(struct device *dev)
 287 {
 288         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 289         struct ad5446_state *st = iio_priv(indio_dev);
 290
 291         iio_device_unregister(indio_dev);
 292         if (!IS_ERR(st->reg))
 293                 regulator_disable(st->reg);
 294
 295         return 0;
 296 }
 297
 298 #if IS_ENABLED(CONFIG_SPI_MASTER)
 299
 300 static int ad5446_write(struct ad5446_state *st, unsigned val)
 301 {
 302         struct spi_device *spi = to_spi_device(st->dev);
 303         __be16 data = cpu_to_be16(val);
 304
 305         return spi_write(spi, &data, sizeof(data));
 306 }
 307
 308 static int ad5660_write(struct ad5446_state *st, unsigned val)
 309 {
 310         struct spi_device *spi = to_spi_device(st->dev);
 311         uint8_t data[3];
 312
 313         put_unaligned_be24(val, &data[0]);
 314
 315         return spi_write(spi, data, sizeof(data));
 316 }
 317
 318 /*
 319  * ad5446_supported_spi_device_ids:
 320  * The AD5620/40/60 parts are available in different fixed internal reference
 321  * voltage options. The actual part numbers may look differently
 322  * (and a bit cryptic), however this style is used to make clear which
 323  * parts are supported here.
 324  */
 325 enum ad5446_supported_spi_device_ids {
 326         ID_AD5300,
 327         ID_AD5310,
 328         ID_AD5320,
 329         ID_AD5444,
 330         ID_AD5446,
 331         ID_AD5450,
 332         ID_AD5451,
 333         ID_AD5541A,
 334         ID_AD5512A,
 335         ID_AD5553,
 336         ID_AD5600,
 337         ID_AD5601,
 338         ID_AD5611,
 339         ID_AD5621,
 340         ID_AD5641,
 341         ID_AD5620_2500,
 342         ID_AD5620_1250,
 343         ID_AD5640_2500,
 344         ID_AD5640_1250,
 345         ID_AD5660_2500,
 346         ID_AD5660_1250,
 347         ID_AD5662,
 348 };
 349
 350 static const struct ad5446_chip_info ad5446_spi_chip_info[] = {
 351         [ID_AD5300] = {
 352                 .channel = AD5446_CHANNEL_POWERDOWN(8, 16, 4),
 353                 .write = ad5446_write,
 354         },
 355         [ID_AD5310] = {
 356                 .channel = AD5446_CHANNEL_POWERDOWN(10, 16, 2),
 357                 .write = ad5446_write,
 358         },
 359         [ID_AD5320] = {
 360                 .channel = AD5446_CHANNEL_POWERDOWN(12, 16, 0),
 361                 .write = ad5446_write,
 362         },
 363         [ID_AD5444] = {
 364                 .channel = AD5446_CHANNEL(12, 16, 2),
 365                 .write = ad5446_write,
 366         },
 367         [ID_AD5446] = {
 368                 .channel = AD5446_CHANNEL(14, 16, 0),
 369                 .write = ad5446_write,
 370         },
 371         [ID_AD5450] = {
 372                 .channel = AD5446_CHANNEL(8, 16, 6),
 373                 .write = ad5446_write,
 374         },
 375         [ID_AD5451] = {
 376                 .channel = AD5446_CHANNEL(10, 16, 4),
 377                 .write = ad5446_write,
 378         },
 379         [ID_AD5541A] = {
 380                 .channel = AD5446_CHANNEL(16, 16, 0),
 381                 .write = ad5446_write,
 382         },
 383         [ID_AD5512A] = {
 384                 .channel = AD5446_CHANNEL(12, 16, 4),
 385                 .write = ad5446_write,
 386         },
 387         [ID_AD5553] = {
 388                 .channel = AD5446_CHANNEL(14, 16, 0),
 389                 .write = ad5446_write,
 390         },
 391         [ID_AD5600] = {
 392                 .channel = AD5446_CHANNEL(16, 16, 0),
 393                 .write = ad5446_write,
 394         },
 395         [ID_AD5601] = {
 396                 .channel = AD5446_CHANNEL_POWERDOWN(8, 16, 6),
 397                 .write = ad5446_write,
 398         },
 399         [ID_AD5611] = {
 400                 .channel = AD5446_CHANNEL_POWERDOWN(10, 16, 4),
 401                 .write = ad5446_write,
 402         },
 403         [ID_AD5621] = {
 404                 .channel = AD5446_CHANNEL_POWERDOWN(12, 16, 2),
 405                 .write = ad5446_write,
 406         },
 407         [ID_AD5641] = {
 408                 .channel = AD5446_CHANNEL_POWERDOWN(14, 16, 0),
 409                 .write = ad5446_write,
 410         },
 411         [ID_AD5620_2500] = {
 412                 .channel = AD5446_CHANNEL_POWERDOWN(12, 16, 2),
 413                 .int_vref_mv = 2500,
 414                 .write = ad5446_write,
 415         },
 416         [ID_AD5620_1250] = {
 417                 .channel = AD5446_CHANNEL_POWERDOWN(12, 16, 2),
 418                 .int_vref_mv = 1250,
 419                 .write = ad5446_write,
 420         },
 421         [ID_AD5640_2500] = {
 422                 .channel = AD5446_CHANNEL_POWERDOWN(14, 16, 0),
 423                 .int_vref_mv = 2500,
 424                 .write = ad5446_write,
 425         },
 426         [ID_AD5640_1250] = {
 427                 .channel = AD5446_CHANNEL_POWERDOWN(14, 16, 0),
 428                 .int_vref_mv = 1250,
 429                 .write = ad5446_write,
 430         },
 431         [ID_AD5660_2500] = {
 432                 .channel = AD5446_CHANNEL_POWERDOWN(16, 16, 0),
 433                 .int_vref_mv = 2500,
 434                 .write = ad5660_write,
 435         },
 436         [ID_AD5660_1250] = {
 437                 .channel = AD5446_CHANNEL_POWERDOWN(16, 16, 0),
 438                 .int_vref_mv = 1250,
 439                 .write = ad5660_write,
 440         },
 441         [ID_AD5662] = {
 442                 .channel = AD5446_CHANNEL_POWERDOWN(16, 16, 0),
 443                 .write = ad5660_write,
 444         },
 445 };
 446
 447 static const struct spi_device_id ad5446_spi_ids[] = {
 448         {"ad5300", ID_AD5300},
 449         {"ad5310", ID_AD5310},
 450         {"ad5320", ID_AD5320},
 451         {"ad5444", ID_AD5444},
 452         {"ad5446", ID_AD5446},
 453         {"ad5450", ID_AD5450},
 454         {"ad5451", ID_AD5451},
 455         {"ad5452", ID_AD5444}, /* ad5452 is compatible to the ad5444 */
 456         {"ad5453", ID_AD5446}, /* ad5453 is compatible to the ad5446 */
 457         {"ad5512a", ID_AD5512A},
 458         {"ad5541a", ID_AD5541A},
 459         {"ad5542a", ID_AD5541A}, /* ad5541a and ad5542a are compatible */
 460         {"ad5543", ID_AD5541A}, /* ad5541a and ad5543 are compatible */
 461         {"ad5553", ID_AD5553},
 462         {"ad5600", ID_AD5600},
 463         {"ad5601", ID_AD5601},
 464         {"ad5611", ID_AD5611},
 465         {"ad5621", ID_AD5621},
 466         {"ad5641", ID_AD5641},
 467         {"ad5620-2500", ID_AD5620_2500}, /* AD5620/40/60: */
 468         {"ad5620-1250", ID_AD5620_1250}, /* part numbers may look differently */
 469         {"ad5640-2500", ID_AD5640_2500},
 470         {"ad5640-1250", ID_AD5640_1250},
 471         {"ad5660-2500", ID_AD5660_2500},
 472         {"ad5660-1250", ID_AD5660_1250},
 473         {"ad5662", ID_AD5662},
 474         {"dac081s101", ID_AD5300}, /* compatible Texas Instruments chips */
 475         {"dac101s101", ID_AD5310},
 476         {"dac121s101", ID_AD5320},
 477         {"dac7512", ID_AD5320},
 478         {}
 479 };
 480 MODULE_DEVICE_TABLE(spi, ad5446_spi_ids);
 481
 482 static const struct of_device_id ad5446_of_ids[] = {
 483         { .compatible = "ti,dac7512" },
 484         { }
 485 };
 486 MODULE_DEVICE_TABLE(of, ad5446_of_ids);
 487
 488 static int ad5446_spi_probe(struct spi_device *spi)
 489 {
 490         const struct spi_device_id *id = spi_get_device_id(spi);
 491
 492         return ad5446_probe(&spi->dev, id->name,
 493                 &ad5446_spi_chip_info[id->driver_data]);
 494 }
 495
 496 static int ad5446_spi_remove(struct spi_device *spi)
 497 {
 498         return ad5446_remove(&spi->dev);
 499 }
 500
 501 static struct spi_driver ad5446_spi_driver = {
 502         .driver = {
 503                 .name   = "ad5446",
 504                 .of_match_table = ad5446_of_ids,
 505         },
 506         .probe          = ad5446_spi_probe,
 507         .remove         = ad5446_spi_remove,
 508         .id_table       = ad5446_spi_ids,
 509 };
 510
 511 static int __init ad5446_spi_register_driver(void)
 512 {
 513         return spi_register_driver(&ad5446_spi_driver);
 514 }
 515
 516 static void ad5446_spi_unregister_driver(void)
 517 {
 518         spi_unregister_driver(&ad5446_spi_driver);
 519 }
 520
 521 #else
 522
 523 static inline int ad5446_spi_register_driver(void) { return 0; }
 524 static inline void ad5446_spi_unregister_driver(void) { }
 525
 526 #endif
 527
 528 #if IS_ENABLED(CONFIG_I2C)
 529
 530 static int ad5622_write(struct ad5446_state *st, unsigned val)
 531 {
 532         struct i2c_client *client = to_i2c_client(st->dev);
 533         __be16 data = cpu_to_be16(val);
 534
 535         return i2c_master_send(client, (char *)&data, sizeof(data));
 536 }
 537
 538 /*
 539  * ad5446_supported_i2c_device_ids:
 540  * The AD5620/40/60 parts are available in different fixed internal reference
 541  * voltage options. The actual part numbers may look differently
 542  * (and a bit cryptic), however this style is used to make clear which
 543  * parts are supported here.
 544  */
 545 enum ad5446_supported_i2c_device_ids {
 546         ID_AD5602,
 547         ID_AD5612,
 548         ID_AD5622,
 549 };
 550
 551 static const struct ad5446_chip_info ad5446_i2c_chip_info[] = {
 552         [ID_AD5602] = {
 553                 .channel = AD5446_CHANNEL_POWERDOWN(8, 16, 4),
 554                 .write = ad5622_write,
 555         },
 556         [ID_AD5612] = {
 557                 .channel = AD5446_CHANNEL_POWERDOWN(10, 16, 2),
 558                 .write = ad5622_write,
 559         },
 560         [ID_AD5622] = {
 561                 .channel = AD5446_CHANNEL_POWERDOWN(12, 16, 0),
 562                 .write = ad5622_write,
 563         },
 564 };
 565
 566 static int ad5446_i2c_probe(struct i2c_client *i2c,
 567                             const struct i2c_device_id *id)
 568 {
 569         return ad5446_probe(&i2c->dev, id->name,
 570                 &ad5446_i2c_chip_info[id->driver_data]);
 571 }
 572
 573 static int ad5446_i2c_remove(struct i2c_client *i2c)
 574 {
 575         return ad5446_remove(&i2c->dev);
 576 }
 577
 578 static const struct i2c_device_id ad5446_i2c_ids[] = {
 579         {"ad5301", ID_AD5602},
 580         {"ad5311", ID_AD5612},
 581         {"ad5321", ID_AD5622},
 582         {"ad5602", ID_AD5602},
 583         {"ad5612", ID_AD5612},
 584         {"ad5622", ID_AD5622},
 585         {}
 586 };
 587 MODULE_DEVICE_TABLE(i2c, ad5446_i2c_ids);
 588
 589 static struct i2c_driver ad5446_i2c_driver = {
 590         .driver = {
 591                    .name = "ad5446",
 592         },
 593         .probe = ad5446_i2c_probe,
 594         .remove = ad5446_i2c_remove,
 595         .id_table = ad5446_i2c_ids,
 596 };
 597
 598 static int __init ad5446_i2c_register_driver(void)
 599 {
 600         return i2c_add_driver(&ad5446_i2c_driver);
 601 }
 602
 603 static void __exit ad5446_i2c_unregister_driver(void)
 604 {
 605         i2c_del_driver(&ad5446_i2c_driver);
 606 }
 607
 608 #else
 609
 610 static inline int ad5446_i2c_register_driver(void) { return 0; }
 611 static inline void ad5446_i2c_unregister_driver(void) { }
 612
 613 #endif
 614
 615 static int __init ad5446_init(void)
 616 {
 617         int ret;
 618
 619         ret = ad5446_spi_register_driver();
 620         if (ret)
 621                 return ret;
 622
 623         ret = ad5446_i2c_register_driver();
 624         if (ret) {
 625                 ad5446_spi_unregister_driver();
 626                 return ret;
 627         }
 628
 629         return 0;
 630 }
 631 module_init(ad5446_init);
 632
 633 static void __exit ad5446_exit(void)
 634 {
 635         ad5446_i2c_unregister_driver();
 636         ad5446_spi_unregister_driver();
 637 }
 638 module_exit(ad5446_exit);
 639
 640 MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
 641 MODULE_DESCRIPTION("Analog Devices AD5444/AD5446 DAC");
 642 MODULE_LICENSE("GPL v2");