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 .driver_module = THIS_MODULE, 216 }; 217 218 static int ad5446_probe(struct device *dev, const char *name, 219 const struct ad5446_chip_info *chip_info) 220 { 221 struct ad5446_state *st; 222 struct iio_dev *indio_dev; 223 struct regulator *reg; 224 int ret, voltage_uv = 0; 225 226 reg = devm_regulator_get(dev, "vcc"); 227 if (!IS_ERR(reg)) { 228 ret = regulator_enable(reg); 229 if (ret) 230 return ret; 231 232 ret = regulator_get_voltage(reg); 233 if (ret < 0) 234 goto error_disable_reg; 235 236 voltage_uv = ret; 237 } 238 239 indio_dev = devm_iio_device_alloc(dev, sizeof(*st)); 240 if (indio_dev == NULL) { 241 ret = -ENOMEM; 242 goto error_disable_reg; 243 } 244 st = iio_priv(indio_dev); 245 st->chip_info = chip_info; 246 247 dev_set_drvdata(dev, indio_dev); 248 st->reg = reg; 249 st->dev = dev; 250 251 /* Establish that the iio_dev is a child of the device */ 252 indio_dev->dev.parent = dev; 253 indio_dev->name = name; 254 indio_dev->info = &ad5446_info; 255 indio_dev->modes = INDIO_DIRECT_MODE; 256 indio_dev->channels = &st->chip_info->channel; 257 indio_dev->num_channels = 1; 258 259 st->pwr_down_mode = MODE_PWRDWN_1k; 260 261 if (st->chip_info->int_vref_mv) 262 st->vref_mv = st->chip_info->int_vref_mv; 263 else if (voltage_uv) 264 st->vref_mv = voltage_uv / 1000; 265 else 266 dev_warn(dev, "reference voltage unspecified\n"); 267 268 ret = iio_device_register(indio_dev); 269 if (ret) 270 goto error_disable_reg; 271 272 return 0; 273 274 error_disable_reg: 275 if (!IS_ERR(reg)) 276 regulator_disable(reg); 277 return ret; 278 } 279 280 static int ad5446_remove(struct device *dev) 281 { 282 struct iio_dev *indio_dev = dev_get_drvdata(dev); 283 struct ad5446_state *st = iio_priv(indio_dev); 284 285 iio_device_unregister(indio_dev); 286 if (!IS_ERR(st->reg)) 287 regulator_disable(st->reg); 288 289 return 0; 290 } 291 292 #if IS_ENABLED(CONFIG_SPI_MASTER) 293 294 static int ad5446_write(struct ad5446_state *st, unsigned val) 295 { 296 struct spi_device *spi = to_spi_device(st->dev); 297 __be16 data = cpu_to_be16(val); 298 299 return spi_write(spi, &data, sizeof(data)); 300 } 301 302 static int ad5660_write(struct ad5446_state *st, unsigned val) 303 { 304 struct spi_device *spi = to_spi_device(st->dev); 305 uint8_t data[3]; 306 307 data[0] = (val >> 16) & 0xFF; 308 data[1] = (val >> 8) & 0xFF; 309 data[2] = val & 0xFF; 310 311 return spi_write(spi, data, sizeof(data)); 312 } 313 314 /** 315 * ad5446_supported_spi_device_ids: 316 * The AD5620/40/60 parts are available in different fixed internal reference 317 * voltage options. The actual part numbers may look differently 318 * (and a bit cryptic), however this style is used to make clear which 319 * parts are supported here. 320 */ 321 enum ad5446_supported_spi_device_ids { 322 ID_AD5300, 323 ID_AD5310, 324 ID_AD5320, 325 ID_AD5444, 326 ID_AD5446, 327 ID_AD5450, 328 ID_AD5451, 329 ID_AD5541A, 330 ID_AD5512A, 331 ID_AD5553, 332 ID_AD5601, 333 ID_AD5611, 334 ID_AD5621, 335 ID_AD5641, 336 ID_AD5620_2500, 337 ID_AD5620_1250, 338 ID_AD5640_2500, 339 ID_AD5640_1250, 340 ID_AD5660_2500, 341 ID_AD5660_1250, 342 ID_AD5662, 343 }; 344 345 static const struct ad5446_chip_info ad5446_spi_chip_info[] = { 346 [ID_AD5300] = { 347 .channel = AD5446_CHANNEL_POWERDOWN(8, 16, 4), 348 .write = ad5446_write, 349 }, 350 [ID_AD5310] = { 351 .channel = AD5446_CHANNEL_POWERDOWN(10, 16, 2), 352 .write = ad5446_write, 353 }, 354 [ID_AD5320] = { 355 .channel = AD5446_CHANNEL_POWERDOWN(12, 16, 0), 356 .write = ad5446_write, 357 }, 358 [ID_AD5444] = { 359 .channel = AD5446_CHANNEL(12, 16, 2), 360 .write = ad5446_write, 361 }, 362 [ID_AD5446] = { 363 .channel = AD5446_CHANNEL(14, 16, 0), 364 .write = ad5446_write, 365 }, 366 [ID_AD5450] = { 367 .channel = AD5446_CHANNEL(8, 16, 6), 368 .write = ad5446_write, 369 }, 370 [ID_AD5451] = { 371 .channel = AD5446_CHANNEL(10, 16, 4), 372 .write = ad5446_write, 373 }, 374 [ID_AD5541A] = { 375 .channel = AD5446_CHANNEL(16, 16, 0), 376 .write = ad5446_write, 377 }, 378 [ID_AD5512A] = { 379 .channel = AD5446_CHANNEL(12, 16, 4), 380 .write = ad5446_write, 381 }, 382 [ID_AD5553] = { 383 .channel = AD5446_CHANNEL(14, 16, 0), 384 .write = ad5446_write, 385 }, 386 [ID_AD5601] = { 387 .channel = AD5446_CHANNEL_POWERDOWN(8, 16, 6), 388 .write = ad5446_write, 389 }, 390 [ID_AD5611] = { 391 .channel = AD5446_CHANNEL_POWERDOWN(10, 16, 4), 392 .write = ad5446_write, 393 }, 394 [ID_AD5621] = { 395 .channel = AD5446_CHANNEL_POWERDOWN(12, 16, 2), 396 .write = ad5446_write, 397 }, 398 [ID_AD5641] = { 399 .channel = AD5446_CHANNEL_POWERDOWN(14, 16, 0), 400 .write = ad5446_write, 401 }, 402 [ID_AD5620_2500] = { 403 .channel = AD5446_CHANNEL_POWERDOWN(12, 16, 2), 404 .int_vref_mv = 2500, 405 .write = ad5446_write, 406 }, 407 [ID_AD5620_1250] = { 408 .channel = AD5446_CHANNEL_POWERDOWN(12, 16, 2), 409 .int_vref_mv = 1250, 410 .write = ad5446_write, 411 }, 412 [ID_AD5640_2500] = { 413 .channel = AD5446_CHANNEL_POWERDOWN(14, 16, 0), 414 .int_vref_mv = 2500, 415 .write = ad5446_write, 416 }, 417 [ID_AD5640_1250] = { 418 .channel = AD5446_CHANNEL_POWERDOWN(14, 16, 0), 419 .int_vref_mv = 1250, 420 .write = ad5446_write, 421 }, 422 [ID_AD5660_2500] = { 423 .channel = AD5446_CHANNEL_POWERDOWN(16, 16, 0), 424 .int_vref_mv = 2500, 425 .write = ad5660_write, 426 }, 427 [ID_AD5660_1250] = { 428 .channel = AD5446_CHANNEL_POWERDOWN(16, 16, 0), 429 .int_vref_mv = 1250, 430 .write = ad5660_write, 431 }, 432 [ID_AD5662] = { 433 .channel = AD5446_CHANNEL_POWERDOWN(16, 16, 0), 434 .write = ad5660_write, 435 }, 436 }; 437 438 static const struct spi_device_id ad5446_spi_ids[] = { 439 {"ad5300", ID_AD5300}, 440 {"ad5310", ID_AD5310}, 441 {"ad5320", ID_AD5320}, 442 {"ad5444", ID_AD5444}, 443 {"ad5446", ID_AD5446}, 444 {"ad5450", ID_AD5450}, 445 {"ad5451", ID_AD5451}, 446 {"ad5452", ID_AD5444}, /* ad5452 is compatible to the ad5444 */ 447 {"ad5453", ID_AD5446}, /* ad5453 is compatible to the ad5446 */ 448 {"ad5512a", ID_AD5512A}, 449 {"ad5541a", ID_AD5541A}, 450 {"ad5542a", ID_AD5541A}, /* ad5541a and ad5542a are compatible */ 451 {"ad5543", ID_AD5541A}, /* ad5541a and ad5543 are compatible */ 452 {"ad5553", ID_AD5553}, 453 {"ad5601", ID_AD5601}, 454 {"ad5611", ID_AD5611}, 455 {"ad5621", ID_AD5621}, 456 {"ad5641", ID_AD5641}, 457 {"ad5620-2500", ID_AD5620_2500}, /* AD5620/40/60: */ 458 {"ad5620-1250", ID_AD5620_1250}, /* part numbers may look differently */ 459 {"ad5640-2500", ID_AD5640_2500}, 460 {"ad5640-1250", ID_AD5640_1250}, 461 {"ad5660-2500", ID_AD5660_2500}, 462 {"ad5660-1250", ID_AD5660_1250}, 463 {"ad5662", ID_AD5662}, 464 {} 465 }; 466 MODULE_DEVICE_TABLE(spi, ad5446_spi_ids); 467 468 static int ad5446_spi_probe(struct spi_device *spi) 469 { 470 const struct spi_device_id *id = spi_get_device_id(spi); 471 472 return ad5446_probe(&spi->dev, id->name, 473 &ad5446_spi_chip_info[id->driver_data]); 474 } 475 476 static int ad5446_spi_remove(struct spi_device *spi) 477 { 478 return ad5446_remove(&spi->dev); 479 } 480 481 static struct spi_driver ad5446_spi_driver = { 482 .driver = { 483 .name = "ad5446", 484 .owner = THIS_MODULE, 485 }, 486 .probe = ad5446_spi_probe, 487 .remove = ad5446_spi_remove, 488 .id_table = ad5446_spi_ids, 489 }; 490 491 static int __init ad5446_spi_register_driver(void) 492 { 493 return spi_register_driver(&ad5446_spi_driver); 494 } 495 496 static void ad5446_spi_unregister_driver(void) 497 { 498 spi_unregister_driver(&ad5446_spi_driver); 499 } 500 501 #else 502 503 static inline int ad5446_spi_register_driver(void) { return 0; } 504 static inline void ad5446_spi_unregister_driver(void) { } 505 506 #endif 507 508 #if IS_ENABLED(CONFIG_I2C) 509 510 static int ad5622_write(struct ad5446_state *st, unsigned val) 511 { 512 struct i2c_client *client = to_i2c_client(st->dev); 513 __be16 data = cpu_to_be16(val); 514 515 return i2c_master_send(client, (char *)&data, sizeof(data)); 516 } 517 518 /** 519 * ad5446_supported_i2c_device_ids: 520 * The AD5620/40/60 parts are available in different fixed internal reference 521 * voltage options. The actual part numbers may look differently 522 * (and a bit cryptic), however this style is used to make clear which 523 * parts are supported here. 524 */ 525 enum ad5446_supported_i2c_device_ids { 526 ID_AD5602, 527 ID_AD5612, 528 ID_AD5622, 529 }; 530 531 static const struct ad5446_chip_info ad5446_i2c_chip_info[] = { 532 [ID_AD5602] = { 533 .channel = AD5446_CHANNEL_POWERDOWN(8, 16, 4), 534 .write = ad5622_write, 535 }, 536 [ID_AD5612] = { 537 .channel = AD5446_CHANNEL_POWERDOWN(10, 16, 2), 538 .write = ad5622_write, 539 }, 540 [ID_AD5622] = { 541 .channel = AD5446_CHANNEL_POWERDOWN(12, 16, 0), 542 .write = ad5622_write, 543 }, 544 }; 545 546 static int ad5446_i2c_probe(struct i2c_client *i2c, 547 const struct i2c_device_id *id) 548 { 549 return ad5446_probe(&i2c->dev, id->name, 550 &ad5446_i2c_chip_info[id->driver_data]); 551 } 552 553 static int ad5446_i2c_remove(struct i2c_client *i2c) 554 { 555 return ad5446_remove(&i2c->dev); 556 } 557 558 static const struct i2c_device_id ad5446_i2c_ids[] = { 559 {"ad5301", ID_AD5602}, 560 {"ad5311", ID_AD5612}, 561 {"ad5321", ID_AD5622}, 562 {"ad5602", ID_AD5602}, 563 {"ad5612", ID_AD5612}, 564 {"ad5622", ID_AD5622}, 565 {} 566 }; 567 MODULE_DEVICE_TABLE(i2c, ad5446_i2c_ids); 568 569 static struct i2c_driver ad5446_i2c_driver = { 570 .driver = { 571 .name = "ad5446", 572 .owner = THIS_MODULE, 573 }, 574 .probe = ad5446_i2c_probe, 575 .remove = ad5446_i2c_remove, 576 .id_table = ad5446_i2c_ids, 577 }; 578 579 static int __init ad5446_i2c_register_driver(void) 580 { 581 return i2c_add_driver(&ad5446_i2c_driver); 582 } 583 584 static void __exit ad5446_i2c_unregister_driver(void) 585 { 586 i2c_del_driver(&ad5446_i2c_driver); 587 } 588 589 #else 590 591 static inline int ad5446_i2c_register_driver(void) { return 0; } 592 static inline void ad5446_i2c_unregister_driver(void) { } 593 594 #endif 595 596 static int __init ad5446_init(void) 597 { 598 int ret; 599 600 ret = ad5446_spi_register_driver(); 601 if (ret) 602 return ret; 603 604 ret = ad5446_i2c_register_driver(); 605 if (ret) { 606 ad5446_spi_unregister_driver(); 607 return ret; 608 } 609 610 return 0; 611 } 612 module_init(ad5446_init); 613 614 static void __exit ad5446_exit(void) 615 { 616 ad5446_i2c_unregister_driver(); 617 ad5446_spi_unregister_driver(); 618 } 619 module_exit(ad5446_exit); 620 621 MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>"); 622 MODULE_DESCRIPTION("Analog Devices AD5444/AD5446 DAC"); 623 MODULE_LICENSE("GPL v2"); 624