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         },
 136         IIO_ENUM("powerdown_mode", false, &ad5446_powerdown_mode_enum),
 137         IIO_ENUM_AVAILABLE("powerdown_mode", &ad5446_powerdown_mode_enum),
 138         { },
 139 };
 140
 141 #define _AD5446_CHANNEL(bits, storage, shift, ext) { \
 142         .type = IIO_VOLTAGE, \
 143         .indexed = 1, \
 144         .output = 1, \
 145         .channel = 0, \
 146         .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
 147         .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
 148         .scan_type = IIO_ST('u', (bits), (storage), (shift)), \
 149         .ext_info = (ext), \
 150 }
 151
 152 #define AD5446_CHANNEL(bits, storage, shift) \
 153         _AD5446_CHANNEL(bits, storage, shift, NULL)
 154
 155 #define AD5446_CHANNEL_POWERDOWN(bits, storage, shift) \
 156         _AD5446_CHANNEL(bits, storage, shift, ad5446_ext_info_powerdown)
 157
 158 static int ad5446_read_raw(struct iio_dev *indio_dev,
 159                            struct iio_chan_spec const *chan,
 160                            int *val,
 161                            int *val2,
 162                            long m)
 163 {
 164         struct ad5446_state *st = iio_priv(indio_dev);
 165         unsigned long scale_uv;
 166
 167         switch (m) {
 168         case IIO_CHAN_INFO_RAW:
 169                 *val = st->cached_val;
 170                 return IIO_VAL_INT;
 171         case IIO_CHAN_INFO_SCALE:
 172                 scale_uv = (st->vref_mv * 1000) >> chan->scan_type.realbits;
 173                 *val =  scale_uv / 1000;
 174                 *val2 = (scale_uv % 1000) * 1000;
 175                 return IIO_VAL_INT_PLUS_MICRO;
 176
 177         }
 178         return -EINVAL;
 179 }
 180
 181 static int ad5446_write_raw(struct iio_dev *indio_dev,
 182                                struct iio_chan_spec const *chan,
 183                                int val,
 184                                int val2,
 185                                long mask)
 186 {
 187         struct ad5446_state *st = iio_priv(indio_dev);
 188         int ret = 0;
 189
 190         switch (mask) {
 191         case IIO_CHAN_INFO_RAW:
 192                 if (val >= (1 << chan->scan_type.realbits) || val < 0)
 193                         return -EINVAL;
 194
 195                 val <<= chan->scan_type.shift;
 196                 mutex_lock(&indio_dev->mlock);
 197                 st->cached_val = val;
 198                 if (!st->pwr_down)
 199                         ret = st->chip_info->write(st, val);
 200                 mutex_unlock(&indio_dev->mlock);
 201                 break;
 202         default:
 203                 ret = -EINVAL;
 204         }
 205
 206         return ret;
 207 }
 208
 209 static const struct iio_info ad5446_info = {
 210         .read_raw = ad5446_read_raw,
 211         .write_raw = ad5446_write_raw,
 212         .driver_module = THIS_MODULE,
 213 };
 214
 215 static int ad5446_probe(struct device *dev, const char *name,
 216                         const struct ad5446_chip_info *chip_info)
 217 {
 218         struct ad5446_state *st;
 219         struct iio_dev *indio_dev;
 220         struct regulator *reg;
 221         int ret, voltage_uv = 0;
 222
 223         reg = devm_regulator_get(dev, "vcc");
 224         if (!IS_ERR(reg)) {
 225                 ret = regulator_enable(reg);
 226                 if (ret)
 227                         return ret;
 228
 229                 ret = regulator_get_voltage(reg);
 230                 if (ret < 0)
 231                         goto error_disable_reg;
 232
 233                 voltage_uv = ret;
 234         }
 235
 236         indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
 237         if (indio_dev == NULL) {
 238                 ret = -ENOMEM;
 239                 goto error_disable_reg;
 240         }
 241         st = iio_priv(indio_dev);
 242         st->chip_info = chip_info;
 243
 244         dev_set_drvdata(dev, indio_dev);
 245         st->reg = reg;
 246         st->dev = dev;
 247
 248         /* Establish that the iio_dev is a child of the device */
 249         indio_dev->dev.parent = dev;
 250         indio_dev->name = name;
 251         indio_dev->info = &ad5446_info;
 252         indio_dev->modes = INDIO_DIRECT_MODE;
 253         indio_dev->channels = &st->chip_info->channel;
 254         indio_dev->num_channels = 1;
 255
 256         st->pwr_down_mode = MODE_PWRDWN_1k;
 257
 258         if (st->chip_info->int_vref_mv)
 259                 st->vref_mv = st->chip_info->int_vref_mv;
 260         else if (voltage_uv)
 261                 st->vref_mv = voltage_uv / 1000;
 262         else
 263                 dev_warn(dev, "reference voltage unspecified\n");
 264
 265         ret = iio_device_register(indio_dev);
 266         if (ret)
 267                 goto error_disable_reg;
 268
 269         return 0;
 270
 271 error_disable_reg:
 272         if (!IS_ERR(reg))
 273                 regulator_disable(reg);
 274         return ret;
 275 }
 276
 277 static int ad5446_remove(struct device *dev)
 278 {
 279         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 280         struct ad5446_state *st = iio_priv(indio_dev);
 281
 282         iio_device_unregister(indio_dev);
 283         if (!IS_ERR(st->reg))
 284                 regulator_disable(st->reg);
 285
 286         return 0;
 287 }
 288
 289 #if IS_ENABLED(CONFIG_SPI_MASTER)
 290
 291 static int ad5446_write(struct ad5446_state *st, unsigned val)
 292 {
 293         struct spi_device *spi = to_spi_device(st->dev);
 294         __be16 data = cpu_to_be16(val);
 295
 296         return spi_write(spi, &data, sizeof(data));
 297 }
 298
 299 static int ad5660_write(struct ad5446_state *st, unsigned val)
 300 {
 301         struct spi_device *spi = to_spi_device(st->dev);
 302         uint8_t data[3];
 303
 304         data[0] = (val >> 16) & 0xFF;
 305         data[1] = (val >> 8) & 0xFF;
 306         data[2] = val & 0xFF;
 307
 308         return spi_write(spi, data, sizeof(data));
 309 }
 310
 311 /**
 312  * ad5446_supported_spi_device_ids:
 313  * The AD5620/40/60 parts are available in different fixed internal reference
 314  * voltage options. The actual part numbers may look differently
 315  * (and a bit cryptic), however this style is used to make clear which
 316  * parts are supported here.
 317  */
 318 enum ad5446_supported_spi_device_ids {
 319         ID_AD5300,
 320         ID_AD5310,
 321         ID_AD5320,
 322         ID_AD5444,
 323         ID_AD5446,
 324         ID_AD5450,
 325         ID_AD5451,
 326         ID_AD5541A,
 327         ID_AD5512A,
 328         ID_AD5553,
 329         ID_AD5601,
 330         ID_AD5611,
 331         ID_AD5621,
 332         ID_AD5620_2500,
 333         ID_AD5620_1250,
 334         ID_AD5640_2500,
 335         ID_AD5640_1250,
 336         ID_AD5660_2500,
 337         ID_AD5660_1250,
 338         ID_AD5662,
 339 };
 340
 341 static const struct ad5446_chip_info ad5446_spi_chip_info[] = {
 342         [ID_AD5300] = {
 343                 .channel = AD5446_CHANNEL_POWERDOWN(8, 16, 4),
 344                 .write = ad5446_write,
 345         },
 346         [ID_AD5310] = {
 347                 .channel = AD5446_CHANNEL_POWERDOWN(10, 16, 2),
 348                 .write = ad5446_write,
 349         },
 350         [ID_AD5320] = {
 351                 .channel = AD5446_CHANNEL_POWERDOWN(12, 16, 0),
 352                 .write = ad5446_write,
 353         },
 354         [ID_AD5444] = {
 355                 .channel = AD5446_CHANNEL(12, 16, 2),
 356                 .write = ad5446_write,
 357         },
 358         [ID_AD5446] = {
 359                 .channel = AD5446_CHANNEL(14, 16, 0),
 360                 .write = ad5446_write,
 361         },
 362         [ID_AD5450] = {
 363                 .channel = AD5446_CHANNEL(8, 16, 6),
 364                 .write = ad5446_write,
 365         },
 366         [ID_AD5451] = {
 367                 .channel = AD5446_CHANNEL(10, 16, 4),
 368                 .write = ad5446_write,
 369         },
 370         [ID_AD5541A] = {
 371                 .channel = AD5446_CHANNEL(16, 16, 0),
 372                 .write = ad5446_write,
 373         },
 374         [ID_AD5512A] = {
 375                 .channel = AD5446_CHANNEL(12, 16, 4),
 376                 .write = ad5446_write,
 377         },
 378         [ID_AD5553] = {
 379                 .channel = AD5446_CHANNEL(14, 16, 0),
 380                 .write = ad5446_write,
 381         },
 382         [ID_AD5601] = {
 383                 .channel = AD5446_CHANNEL_POWERDOWN(8, 16, 6),
 384                 .write = ad5446_write,
 385         },
 386         [ID_AD5611] = {
 387                 .channel = AD5446_CHANNEL_POWERDOWN(10, 16, 4),
 388                 .write = ad5446_write,
 389         },
 390         [ID_AD5621] = {
 391                 .channel = AD5446_CHANNEL_POWERDOWN(12, 16, 2),
 392                 .write = ad5446_write,
 393         },
 394         [ID_AD5620_2500] = {
 395                 .channel = AD5446_CHANNEL_POWERDOWN(12, 16, 2),
 396                 .int_vref_mv = 2500,
 397                 .write = ad5446_write,
 398         },
 399         [ID_AD5620_1250] = {
 400                 .channel = AD5446_CHANNEL_POWERDOWN(12, 16, 2),
 401                 .int_vref_mv = 1250,
 402                 .write = ad5446_write,
 403         },
 404         [ID_AD5640_2500] = {
 405                 .channel = AD5446_CHANNEL_POWERDOWN(14, 16, 0),
 406                 .int_vref_mv = 2500,
 407                 .write = ad5446_write,
 408         },
 409         [ID_AD5640_1250] = {
 410                 .channel = AD5446_CHANNEL_POWERDOWN(14, 16, 0),
 411                 .int_vref_mv = 1250,
 412                 .write = ad5446_write,
 413         },
 414         [ID_AD5660_2500] = {
 415                 .channel = AD5446_CHANNEL_POWERDOWN(16, 16, 0),
 416                 .int_vref_mv = 2500,
 417                 .write = ad5660_write,
 418         },
 419         [ID_AD5660_1250] = {
 420                 .channel = AD5446_CHANNEL_POWERDOWN(16, 16, 0),
 421                 .int_vref_mv = 1250,
 422                 .write = ad5660_write,
 423         },
 424         [ID_AD5662] = {
 425                 .channel = AD5446_CHANNEL_POWERDOWN(16, 16, 0),
 426                 .write = ad5660_write,
 427         },
 428 };
 429
 430 static const struct spi_device_id ad5446_spi_ids[] = {
 431         {"ad5300", ID_AD5300},
 432         {"ad5310", ID_AD5310},
 433         {"ad5320", ID_AD5320},
 434         {"ad5444", ID_AD5444},
 435         {"ad5446", ID_AD5446},
 436         {"ad5450", ID_AD5450},
 437         {"ad5451", ID_AD5451},
 438         {"ad5452", ID_AD5444}, /* ad5452 is compatible to the ad5444 */
 439         {"ad5453", ID_AD5446}, /* ad5453 is compatible to the ad5446 */
 440         {"ad5512a", ID_AD5512A},
 441         {"ad5541a", ID_AD5541A},
 442         {"ad5542a", ID_AD5541A}, /* ad5541a and ad5542a are compatible */
 443         {"ad5543", ID_AD5541A}, /* ad5541a and ad5543 are compatible */
 444         {"ad5553", ID_AD5553},
 445         {"ad5601", ID_AD5601},
 446         {"ad5611", ID_AD5611},
 447         {"ad5621", ID_AD5621},
 448         {"ad5620-2500", ID_AD5620_2500}, /* AD5620/40/60: */
 449         {"ad5620-1250", ID_AD5620_1250}, /* part numbers may look differently */
 450         {"ad5640-2500", ID_AD5640_2500},
 451         {"ad5640-1250", ID_AD5640_1250},
 452         {"ad5660-2500", ID_AD5660_2500},
 453         {"ad5660-1250", ID_AD5660_1250},
 454         {"ad5662", ID_AD5662},
 455         {}
 456 };
 457 MODULE_DEVICE_TABLE(spi, ad5446_spi_ids);
 458
 459 static int ad5446_spi_probe(struct spi_device *spi)
 460 {
 461         const struct spi_device_id *id = spi_get_device_id(spi);
 462
 463         return ad5446_probe(&spi->dev, id->name,
 464                 &ad5446_spi_chip_info[id->driver_data]);
 465 }
 466
 467 static int ad5446_spi_remove(struct spi_device *spi)
 468 {
 469         return ad5446_remove(&spi->dev);
 470 }
 471
 472 static struct spi_driver ad5446_spi_driver = {
 473         .driver = {
 474                 .name   = "ad5446",
 475                 .owner  = THIS_MODULE,
 476         },
 477         .probe          = ad5446_spi_probe,
 478         .remove         = ad5446_spi_remove,
 479         .id_table       = ad5446_spi_ids,
 480 };
 481
 482 static int __init ad5446_spi_register_driver(void)
 483 {
 484         return spi_register_driver(&ad5446_spi_driver);
 485 }
 486
 487 static void ad5446_spi_unregister_driver(void)
 488 {
 489         spi_unregister_driver(&ad5446_spi_driver);
 490 }
 491
 492 #else
 493
 494 static inline int ad5446_spi_register_driver(void) { return 0; }
 495 static inline void ad5446_spi_unregister_driver(void) { }
 496
 497 #endif
 498
 499 #if IS_ENABLED(CONFIG_I2C)
 500
 501 static int ad5622_write(struct ad5446_state *st, unsigned val)
 502 {
 503         struct i2c_client *client = to_i2c_client(st->dev);
 504         __be16 data = cpu_to_be16(val);
 505
 506         return i2c_master_send(client, (char *)&data, sizeof(data));
 507 }
 508
 509 /**
 510  * ad5446_supported_i2c_device_ids:
 511  * The AD5620/40/60 parts are available in different fixed internal reference
 512  * voltage options. The actual part numbers may look differently
 513  * (and a bit cryptic), however this style is used to make clear which
 514  * parts are supported here.
 515  */
 516 enum ad5446_supported_i2c_device_ids {
 517         ID_AD5602,
 518         ID_AD5612,
 519         ID_AD5622,
 520 };
 521
 522 static const struct ad5446_chip_info ad5446_i2c_chip_info[] = {
 523         [ID_AD5602] = {
 524                 .channel = AD5446_CHANNEL_POWERDOWN(8, 16, 4),
 525                 .write = ad5622_write,
 526         },
 527         [ID_AD5612] = {
 528                 .channel = AD5446_CHANNEL_POWERDOWN(10, 16, 2),
 529                 .write = ad5622_write,
 530         },
 531         [ID_AD5622] = {
 532                 .channel = AD5446_CHANNEL_POWERDOWN(12, 16, 0),
 533                 .write = ad5622_write,
 534         },
 535 };
 536
 537 static int ad5446_i2c_probe(struct i2c_client *i2c,
 538                             const struct i2c_device_id *id)
 539 {
 540         return ad5446_probe(&i2c->dev, id->name,
 541                 &ad5446_i2c_chip_info[id->driver_data]);
 542 }
 543
 544 static int ad5446_i2c_remove(struct i2c_client *i2c)
 545 {
 546         return ad5446_remove(&i2c->dev);
 547 }
 548
 549 static const struct i2c_device_id ad5446_i2c_ids[] = {
 550         {"ad5301", ID_AD5602},
 551         {"ad5311", ID_AD5612},
 552         {"ad5321", ID_AD5622},
 553         {"ad5602", ID_AD5602},
 554         {"ad5612", ID_AD5612},
 555         {"ad5622", ID_AD5622},
 556         {}
 557 };
 558 MODULE_DEVICE_TABLE(i2c, ad5446_i2c_ids);
 559
 560 static struct i2c_driver ad5446_i2c_driver = {
 561         .driver = {
 562                    .name = "ad5446",
 563                    .owner = THIS_MODULE,
 564         },
 565         .probe = ad5446_i2c_probe,
 566         .remove = ad5446_i2c_remove,
 567         .id_table = ad5446_i2c_ids,
 568 };
 569
 570 static int __init ad5446_i2c_register_driver(void)
 571 {
 572         return i2c_add_driver(&ad5446_i2c_driver);
 573 }
 574
 575 static void __exit ad5446_i2c_unregister_driver(void)
 576 {
 577         i2c_del_driver(&ad5446_i2c_driver);
 578 }
 579
 580 #else
 581
 582 static inline int ad5446_i2c_register_driver(void) { return 0; }
 583 static inline void ad5446_i2c_unregister_driver(void) { }
 584
 585 #endif
 586
 587 static int __init ad5446_init(void)
 588 {
 589         int ret;
 590
 591         ret = ad5446_spi_register_driver();
 592         if (ret)
 593                 return ret;
 594
 595         ret = ad5446_i2c_register_driver();
 596         if (ret) {
 597                 ad5446_spi_unregister_driver();
 598                 return ret;
 599         }
 600
 601         return 0;
 602 }
 603 module_init(ad5446_init);
 604
 605 static void __exit ad5446_exit(void)
 606 {
 607         ad5446_i2c_unregister_driver();
 608         ad5446_spi_unregister_driver();
 609 }
 610 module_exit(ad5446_exit);
 611
 612 MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
 613 MODULE_DESCRIPTION("Analog Devices AD5444/AD5446 DAC");
 614 MODULE_LICENSE("GPL v2");