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 <linux/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 sysfs_emit(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 = kstrtobool(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", IIO_SHARED_BY_TYPE, &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 >> chan->scan_type.shift;
 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 void 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
 296 #if IS_ENABLED(CONFIG_SPI_MASTER)
 297
 298 static int ad5446_write(struct ad5446_state *st, unsigned val)
 299 {
 300         struct spi_device *spi = to_spi_device(st->dev);
 301         __be16 data = cpu_to_be16(val);
 302
 303         return spi_write(spi, &data, sizeof(data));
 304 }
 305
 306 static int ad5660_write(struct ad5446_state *st, unsigned val)
 307 {
 308         struct spi_device *spi = to_spi_device(st->dev);
 309         uint8_t data[3];
 310
 311         put_unaligned_be24(val, &data[0]);
 312
 313         return spi_write(spi, data, sizeof(data));
 314 }
 315
 316 /*
 317  * ad5446_supported_spi_device_ids:
 318  * The AD5620/40/60 parts are available in different fixed internal reference
 319  * voltage options. The actual part numbers may look differently
 320  * (and a bit cryptic), however this style is used to make clear which
 321  * parts are supported here.
 322  */
 323 enum ad5446_supported_spi_device_ids {
 324         ID_AD5300,
 325         ID_AD5310,
 326         ID_AD5320,
 327         ID_AD5444,
 328         ID_AD5446,
 329         ID_AD5450,
 330         ID_AD5451,
 331         ID_AD5541A,
 332         ID_AD5512A,
 333         ID_AD5553,
 334         ID_AD5600,
 335         ID_AD5601,
 336         ID_AD5611,
 337         ID_AD5621,
 338         ID_AD5641,
 339         ID_AD5620_2500,
 340         ID_AD5620_1250,
 341         ID_AD5640_2500,
 342         ID_AD5640_1250,
 343         ID_AD5660_2500,
 344         ID_AD5660_1250,
 345         ID_AD5662,
 346 };
 347
 348 static const struct ad5446_chip_info ad5446_spi_chip_info[] = {
 349         [ID_AD5300] = {
 350                 .channel = AD5446_CHANNEL_POWERDOWN(8, 16, 4),
 351                 .write = ad5446_write,
 352         },
 353         [ID_AD5310] = {
 354                 .channel = AD5446_CHANNEL_POWERDOWN(10, 16, 2),
 355                 .write = ad5446_write,
 356         },
 357         [ID_AD5320] = {
 358                 .channel = AD5446_CHANNEL_POWERDOWN(12, 16, 0),
 359                 .write = ad5446_write,
 360         },
 361         [ID_AD5444] = {
 362                 .channel = AD5446_CHANNEL(12, 16, 2),
 363                 .write = ad5446_write,
 364         },
 365         [ID_AD5446] = {
 366                 .channel = AD5446_CHANNEL(14, 16, 0),
 367                 .write = ad5446_write,
 368         },
 369         [ID_AD5450] = {
 370                 .channel = AD5446_CHANNEL(8, 16, 6),
 371                 .write = ad5446_write,
 372         },
 373         [ID_AD5451] = {
 374                 .channel = AD5446_CHANNEL(10, 16, 4),
 375                 .write = ad5446_write,
 376         },
 377         [ID_AD5541A] = {
 378                 .channel = AD5446_CHANNEL(16, 16, 0),
 379                 .write = ad5446_write,
 380         },
 381         [ID_AD5512A] = {
 382                 .channel = AD5446_CHANNEL(12, 16, 4),
 383                 .write = ad5446_write,
 384         },
 385         [ID_AD5553] = {
 386                 .channel = AD5446_CHANNEL(14, 16, 0),
 387                 .write = ad5446_write,
 388         },
 389         [ID_AD5600] = {
 390                 .channel = AD5446_CHANNEL(16, 16, 0),
 391                 .write = ad5446_write,
 392         },
 393         [ID_AD5601] = {
 394                 .channel = AD5446_CHANNEL_POWERDOWN(8, 16, 6),
 395                 .write = ad5446_write,
 396         },
 397         [ID_AD5611] = {
 398                 .channel = AD5446_CHANNEL_POWERDOWN(10, 16, 4),
 399                 .write = ad5446_write,
 400         },
 401         [ID_AD5621] = {
 402                 .channel = AD5446_CHANNEL_POWERDOWN(12, 16, 2),
 403                 .write = ad5446_write,
 404         },
 405         [ID_AD5641] = {
 406                 .channel = AD5446_CHANNEL_POWERDOWN(14, 16, 0),
 407                 .write = ad5446_write,
 408         },
 409         [ID_AD5620_2500] = {
 410                 .channel = AD5446_CHANNEL_POWERDOWN(12, 16, 2),
 411                 .int_vref_mv = 2500,
 412                 .write = ad5446_write,
 413         },
 414         [ID_AD5620_1250] = {
 415                 .channel = AD5446_CHANNEL_POWERDOWN(12, 16, 2),
 416                 .int_vref_mv = 1250,
 417                 .write = ad5446_write,
 418         },
 419         [ID_AD5640_2500] = {
 420                 .channel = AD5446_CHANNEL_POWERDOWN(14, 16, 0),
 421                 .int_vref_mv = 2500,
 422                 .write = ad5446_write,
 423         },
 424         [ID_AD5640_1250] = {
 425                 .channel = AD5446_CHANNEL_POWERDOWN(14, 16, 0),
 426                 .int_vref_mv = 1250,
 427                 .write = ad5446_write,
 428         },
 429         [ID_AD5660_2500] = {
 430                 .channel = AD5446_CHANNEL_POWERDOWN(16, 16, 0),
 431                 .int_vref_mv = 2500,
 432                 .write = ad5660_write,
 433         },
 434         [ID_AD5660_1250] = {
 435                 .channel = AD5446_CHANNEL_POWERDOWN(16, 16, 0),
 436                 .int_vref_mv = 1250,
 437                 .write = ad5660_write,
 438         },
 439         [ID_AD5662] = {
 440                 .channel = AD5446_CHANNEL_POWERDOWN(16, 16, 0),
 441                 .write = ad5660_write,
 442         },
 443 };
 444
 445 static const struct spi_device_id ad5446_spi_ids[] = {
 446         {"ad5300", ID_AD5300},
 447         {"ad5310", ID_AD5310},
 448         {"ad5320", ID_AD5320},
 449         {"ad5444", ID_AD5444},
 450         {"ad5446", ID_AD5446},
 451         {"ad5450", ID_AD5450},
 452         {"ad5451", ID_AD5451},
 453         {"ad5452", ID_AD5444}, /* ad5452 is compatible to the ad5444 */
 454         {"ad5453", ID_AD5446}, /* ad5453 is compatible to the ad5446 */
 455         {"ad5512a", ID_AD5512A},
 456         {"ad5541a", ID_AD5541A},
 457         {"ad5542a", ID_AD5541A}, /* ad5541a and ad5542a are compatible */
 458         {"ad5543", ID_AD5541A}, /* ad5541a and ad5543 are compatible */
 459         {"ad5553", ID_AD5553},
 460         {"ad5600", ID_AD5600},
 461         {"ad5601", ID_AD5601},
 462         {"ad5611", ID_AD5611},
 463         {"ad5621", ID_AD5621},
 464         {"ad5641", ID_AD5641},
 465         {"ad5620-2500", ID_AD5620_2500}, /* AD5620/40/60: */
 466         {"ad5620-1250", ID_AD5620_1250}, /* part numbers may look differently */
 467         {"ad5640-2500", ID_AD5640_2500},
 468         {"ad5640-1250", ID_AD5640_1250},
 469         {"ad5660-2500", ID_AD5660_2500},
 470         {"ad5660-1250", ID_AD5660_1250},
 471         {"ad5662", ID_AD5662},
 472         {"dac081s101", ID_AD5300}, /* compatible Texas Instruments chips */
 473         {"dac101s101", ID_AD5310},
 474         {"dac121s101", ID_AD5320},
 475         {"dac7512", ID_AD5320},
 476         {}
 477 };
 478 MODULE_DEVICE_TABLE(spi, ad5446_spi_ids);
 479
 480 static const struct of_device_id ad5446_of_ids[] = {
 481         { .compatible = "ti,dac7512" },
 482         { }
 483 };
 484 MODULE_DEVICE_TABLE(of, ad5446_of_ids);
 485
 486 static int ad5446_spi_probe(struct spi_device *spi)
 487 {
 488         const struct spi_device_id *id = spi_get_device_id(spi);
 489
 490         return ad5446_probe(&spi->dev, id->name,
 491                 &ad5446_spi_chip_info[id->driver_data]);
 492 }
 493
 494 static void ad5446_spi_remove(struct spi_device *spi)
 495 {
 496         ad5446_remove(&spi->dev);
 497 }
 498
 499 static struct spi_driver ad5446_spi_driver = {
 500         .driver = {
 501                 .name   = "ad5446",
 502                 .of_match_table = ad5446_of_ids,
 503         },
 504         .probe          = ad5446_spi_probe,
 505         .remove         = ad5446_spi_remove,
 506         .id_table       = ad5446_spi_ids,
 507 };
 508
 509 static int __init ad5446_spi_register_driver(void)
 510 {
 511         return spi_register_driver(&ad5446_spi_driver);
 512 }
 513
 514 static void ad5446_spi_unregister_driver(void)
 515 {
 516         spi_unregister_driver(&ad5446_spi_driver);
 517 }
 518
 519 #else
 520
 521 static inline int ad5446_spi_register_driver(void) { return 0; }
 522 static inline void ad5446_spi_unregister_driver(void) { }
 523
 524 #endif
 525
 526 #if IS_ENABLED(CONFIG_I2C)
 527
 528 static int ad5622_write(struct ad5446_state *st, unsigned val)
 529 {
 530         struct i2c_client *client = to_i2c_client(st->dev);
 531         __be16 data = cpu_to_be16(val);
 532         int ret;
 533
 534         ret = i2c_master_send(client, (char *)&data, sizeof(data));
 535         if (ret < 0)
 536                 return ret;
 537         if (ret != sizeof(data))
 538                 return -EIO;
 539
 540         return 0;
 541 }
 542
 543 /*
 544  * ad5446_supported_i2c_device_ids:
 545  * The AD5620/40/60 parts are available in different fixed internal reference
 546  * voltage options. The actual part numbers may look differently
 547  * (and a bit cryptic), however this style is used to make clear which
 548  * parts are supported here.
 549  */
 550 enum ad5446_supported_i2c_device_ids {
 551         ID_AD5602,
 552         ID_AD5612,
 553         ID_AD5622,
 554 };
 555
 556 static const struct ad5446_chip_info ad5446_i2c_chip_info[] = {
 557         [ID_AD5602] = {
 558                 .channel = AD5446_CHANNEL_POWERDOWN(8, 16, 4),
 559                 .write = ad5622_write,
 560         },
 561         [ID_AD5612] = {
 562                 .channel = AD5446_CHANNEL_POWERDOWN(10, 16, 2),
 563                 .write = ad5622_write,
 564         },
 565         [ID_AD5622] = {
 566                 .channel = AD5446_CHANNEL_POWERDOWN(12, 16, 0),
 567                 .write = ad5622_write,
 568         },
 569 };
 570
 571 static int ad5446_i2c_probe(struct i2c_client *i2c)
 572 {
 573         const struct i2c_device_id *id = i2c_client_get_device_id(i2c);
 574         return ad5446_probe(&i2c->dev, id->name,
 575                 &ad5446_i2c_chip_info[id->driver_data]);
 576 }
 577
 578 static void ad5446_i2c_remove(struct i2c_client *i2c)
 579 {
 580         ad5446_remove(&i2c->dev);
 581 }
 582
 583 static const struct i2c_device_id ad5446_i2c_ids[] = {
 584         {"ad5301", ID_AD5602},
 585         {"ad5311", ID_AD5612},
 586         {"ad5321", ID_AD5622},
 587         {"ad5602", ID_AD5602},
 588         {"ad5612", ID_AD5612},
 589         {"ad5622", ID_AD5622},
 590         {}
 591 };
 592 MODULE_DEVICE_TABLE(i2c, ad5446_i2c_ids);
 593
 594 static struct i2c_driver ad5446_i2c_driver = {
 595         .driver = {
 596                    .name = "ad5446",
 597         },
 598         .probe = ad5446_i2c_probe,
 599         .remove = ad5446_i2c_remove,
 600         .id_table = ad5446_i2c_ids,
 601 };
 602
 603 static int __init ad5446_i2c_register_driver(void)
 604 {
 605         return i2c_add_driver(&ad5446_i2c_driver);
 606 }
 607
 608 static void __exit ad5446_i2c_unregister_driver(void)
 609 {
 610         i2c_del_driver(&ad5446_i2c_driver);
 611 }
 612
 613 #else
 614
 615 static inline int ad5446_i2c_register_driver(void) { return 0; }
 616 static inline void ad5446_i2c_unregister_driver(void) { }
 617
 618 #endif
 619
 620 static int __init ad5446_init(void)
 621 {
 622         int ret;
 623
 624         ret = ad5446_spi_register_driver();
 625         if (ret)
 626                 return ret;
 627
 628         ret = ad5446_i2c_register_driver();
 629         if (ret) {
 630                 ad5446_spi_unregister_driver();
 631                 return ret;
 632         }
 633
 634         return 0;
 635 }
 636 module_init(ad5446_init);
 637
 638 static void __exit ad5446_exit(void)
 639 {
 640         ad5446_i2c_unregister_driver();
 641         ad5446_spi_unregister_driver();
 642 }
 643 module_exit(ad5446_exit);
 644
 645 MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
 646 MODULE_DESCRIPTION("Analog Devices AD5444/AD5446 DAC");
 647 MODULE_LICENSE("GPL v2");