drivers/iio/dac/ad5446.c

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