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 = IIO_ST('u', (bits), (storage), (shift)), \ 150 .ext_info = (ext), \ 151 } 152 153 #define AD5446_CHANNEL(bits, storage, shift) \ 154 _AD5446_CHANNEL(bits, storage, shift, NULL) 155 156 #define AD5446_CHANNEL_POWERDOWN(bits, storage, shift) \ 157 _AD5446_CHANNEL(bits, storage, shift, ad5446_ext_info_powerdown) 158 159 static int ad5446_read_raw(struct iio_dev *indio_dev, 160 struct iio_chan_spec const *chan, 161 int *val, 162 int *val2, 163 long m) 164 { 165 struct ad5446_state *st = iio_priv(indio_dev); 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 *val = st->vref_mv; 173 *val2 = chan->scan_type.realbits; 174 return IIO_VAL_FRACTIONAL_LOG2; 175 } 176 return -EINVAL; 177 } 178 179 static int ad5446_write_raw(struct iio_dev *indio_dev, 180 struct iio_chan_spec const *chan, 181 int val, 182 int val2, 183 long mask) 184 { 185 struct ad5446_state *st = iio_priv(indio_dev); 186 int ret = 0; 187 188 switch (mask) { 189 case IIO_CHAN_INFO_RAW: 190 if (val >= (1 << chan->scan_type.realbits) || val < 0) 191 return -EINVAL; 192 193 val <<= chan->scan_type.shift; 194 mutex_lock(&indio_dev->mlock); 195 st->cached_val = val; 196 if (!st->pwr_down) 197 ret = st->chip_info->write(st, val); 198 mutex_unlock(&indio_dev->mlock); 199 break; 200 default: 201 ret = -EINVAL; 202 } 203 204 return ret; 205 } 206 207 static const struct iio_info ad5446_info = { 208 .read_raw = ad5446_read_raw, 209 .write_raw = ad5446_write_raw, 210 .driver_module = THIS_MODULE, 211 }; 212 213 static int ad5446_probe(struct device *dev, const char *name, 214 const struct ad5446_chip_info *chip_info) 215 { 216 struct ad5446_state *st; 217 struct iio_dev *indio_dev; 218 struct regulator *reg; 219 int ret, voltage_uv = 0; 220 221 reg = devm_regulator_get(dev, "vcc"); 222 if (!IS_ERR(reg)) { 223 ret = regulator_enable(reg); 224 if (ret) 225 return ret; 226 227 ret = regulator_get_voltage(reg); 228 if (ret < 0) 229 goto error_disable_reg; 230 231 voltage_uv = ret; 232 } 233 234 indio_dev = devm_iio_device_alloc(dev, sizeof(*st)); 235 if (indio_dev == NULL) { 236 ret = -ENOMEM; 237 goto error_disable_reg; 238 } 239 st = iio_priv(indio_dev); 240 st->chip_info = chip_info; 241 242 dev_set_drvdata(dev, indio_dev); 243 st->reg = reg; 244 st->dev = dev; 245 246 /* Establish that the iio_dev is a child of the device */ 247 indio_dev->dev.parent = dev; 248 indio_dev->name = name; 249 indio_dev->info = &ad5446_info; 250 indio_dev->modes = INDIO_DIRECT_MODE; 251 indio_dev->channels = &st->chip_info->channel; 252 indio_dev->num_channels = 1; 253 254 st->pwr_down_mode = MODE_PWRDWN_1k; 255 256 if (st->chip_info->int_vref_mv) 257 st->vref_mv = st->chip_info->int_vref_mv; 258 else if (voltage_uv) 259 st->vref_mv = voltage_uv / 1000; 260 else 261 dev_warn(dev, "reference voltage unspecified\n"); 262 263 ret = iio_device_register(indio_dev); 264 if (ret) 265 goto error_disable_reg; 266 267 return 0; 268 269 error_disable_reg: 270 if (!IS_ERR(reg)) 271 regulator_disable(reg); 272 return ret; 273 } 274 275 static int ad5446_remove(struct device *dev) 276 { 277 struct iio_dev *indio_dev = dev_get_drvdata(dev); 278 struct ad5446_state *st = iio_priv(indio_dev); 279 280 iio_device_unregister(indio_dev); 281 if (!IS_ERR(st->reg)) 282 regulator_disable(st->reg); 283 284 return 0; 285 } 286 287 #if IS_ENABLED(CONFIG_SPI_MASTER) 288 289 static int ad5446_write(struct ad5446_state *st, unsigned val) 290 { 291 struct spi_device *spi = to_spi_device(st->dev); 292 __be16 data = cpu_to_be16(val); 293 294 return spi_write(spi, &data, sizeof(data)); 295 } 296 297 static int ad5660_write(struct ad5446_state *st, unsigned val) 298 { 299 struct spi_device *spi = to_spi_device(st->dev); 300 uint8_t data[3]; 301 302 data[0] = (val >> 16) & 0xFF; 303 data[1] = (val >> 8) & 0xFF; 304 data[2] = val & 0xFF; 305 306 return spi_write(spi, data, sizeof(data)); 307 } 308 309 /** 310 * ad5446_supported_spi_device_ids: 311 * The AD5620/40/60 parts are available in different fixed internal reference 312 * voltage options. The actual part numbers may look differently 313 * (and a bit cryptic), however this style is used to make clear which 314 * parts are supported here. 315 */ 316 enum ad5446_supported_spi_device_ids { 317 ID_AD5300, 318 ID_AD5310, 319 ID_AD5320, 320 ID_AD5444, 321 ID_AD5446, 322 ID_AD5450, 323 ID_AD5451, 324 ID_AD5541A, 325 ID_AD5512A, 326 ID_AD5553, 327 ID_AD5601, 328 ID_AD5611, 329 ID_AD5621, 330 ID_AD5641, 331 ID_AD5620_2500, 332 ID_AD5620_1250, 333 ID_AD5640_2500, 334 ID_AD5640_1250, 335 ID_AD5660_2500, 336 ID_AD5660_1250, 337 ID_AD5662, 338 }; 339 340 static const struct ad5446_chip_info ad5446_spi_chip_info[] = { 341 [ID_AD5300] = { 342 .channel = AD5446_CHANNEL_POWERDOWN(8, 16, 4), 343 .write = ad5446_write, 344 }, 345 [ID_AD5310] = { 346 .channel = AD5446_CHANNEL_POWERDOWN(10, 16, 2), 347 .write = ad5446_write, 348 }, 349 [ID_AD5320] = { 350 .channel = AD5446_CHANNEL_POWERDOWN(12, 16, 0), 351 .write = ad5446_write, 352 }, 353 [ID_AD5444] = { 354 .channel = AD5446_CHANNEL(12, 16, 2), 355 .write = ad5446_write, 356 }, 357 [ID_AD5446] = { 358 .channel = AD5446_CHANNEL(14, 16, 0), 359 .write = ad5446_write, 360 }, 361 [ID_AD5450] = { 362 .channel = AD5446_CHANNEL(8, 16, 6), 363 .write = ad5446_write, 364 }, 365 [ID_AD5451] = { 366 .channel = AD5446_CHANNEL(10, 16, 4), 367 .write = ad5446_write, 368 }, 369 [ID_AD5541A] = { 370 .channel = AD5446_CHANNEL(16, 16, 0), 371 .write = ad5446_write, 372 }, 373 [ID_AD5512A] = { 374 .channel = AD5446_CHANNEL(12, 16, 4), 375 .write = ad5446_write, 376 }, 377 [ID_AD5553] = { 378 .channel = AD5446_CHANNEL(14, 16, 0), 379 .write = ad5446_write, 380 }, 381 [ID_AD5601] = { 382 .channel = AD5446_CHANNEL_POWERDOWN(8, 16, 6), 383 .write = ad5446_write, 384 }, 385 [ID_AD5611] = { 386 .channel = AD5446_CHANNEL_POWERDOWN(10, 16, 4), 387 .write = ad5446_write, 388 }, 389 [ID_AD5621] = { 390 .channel = AD5446_CHANNEL_POWERDOWN(12, 16, 2), 391 .write = ad5446_write, 392 }, 393 [ID_AD5641] = { 394 .channel = AD5446_CHANNEL_POWERDOWN(14, 16, 0), 395 .write = ad5446_write, 396 }, 397 [ID_AD5620_2500] = { 398 .channel = AD5446_CHANNEL_POWERDOWN(12, 16, 2), 399 .int_vref_mv = 2500, 400 .write = ad5446_write, 401 }, 402 [ID_AD5620_1250] = { 403 .channel = AD5446_CHANNEL_POWERDOWN(12, 16, 2), 404 .int_vref_mv = 1250, 405 .write = ad5446_write, 406 }, 407 [ID_AD5640_2500] = { 408 .channel = AD5446_CHANNEL_POWERDOWN(14, 16, 0), 409 .int_vref_mv = 2500, 410 .write = ad5446_write, 411 }, 412 [ID_AD5640_1250] = { 413 .channel = AD5446_CHANNEL_POWERDOWN(14, 16, 0), 414 .int_vref_mv = 1250, 415 .write = ad5446_write, 416 }, 417 [ID_AD5660_2500] = { 418 .channel = AD5446_CHANNEL_POWERDOWN(16, 16, 0), 419 .int_vref_mv = 2500, 420 .write = ad5660_write, 421 }, 422 [ID_AD5660_1250] = { 423 .channel = AD5446_CHANNEL_POWERDOWN(16, 16, 0), 424 .int_vref_mv = 1250, 425 .write = ad5660_write, 426 }, 427 [ID_AD5662] = { 428 .channel = AD5446_CHANNEL_POWERDOWN(16, 16, 0), 429 .write = ad5660_write, 430 }, 431 }; 432 433 static const struct spi_device_id ad5446_spi_ids[] = { 434 {"ad5300", ID_AD5300}, 435 {"ad5310", ID_AD5310}, 436 {"ad5320", ID_AD5320}, 437 {"ad5444", ID_AD5444}, 438 {"ad5446", ID_AD5446}, 439 {"ad5450", ID_AD5450}, 440 {"ad5451", ID_AD5451}, 441 {"ad5452", ID_AD5444}, /* ad5452 is compatible to the ad5444 */ 442 {"ad5453", ID_AD5446}, /* ad5453 is compatible to the ad5446 */ 443 {"ad5512a", ID_AD5512A}, 444 {"ad5541a", ID_AD5541A}, 445 {"ad5542a", ID_AD5541A}, /* ad5541a and ad5542a are compatible */ 446 {"ad5543", ID_AD5541A}, /* ad5541a and ad5543 are compatible */ 447 {"ad5553", ID_AD5553}, 448 {"ad5601", ID_AD5601}, 449 {"ad5611", ID_AD5611}, 450 {"ad5621", ID_AD5621}, 451 {"ad5641", ID_AD5641}, 452 {"ad5620-2500", ID_AD5620_2500}, /* AD5620/40/60: */ 453 {"ad5620-1250", ID_AD5620_1250}, /* part numbers may look differently */ 454 {"ad5640-2500", ID_AD5640_2500}, 455 {"ad5640-1250", ID_AD5640_1250}, 456 {"ad5660-2500", ID_AD5660_2500}, 457 {"ad5660-1250", ID_AD5660_1250}, 458 {"ad5662", ID_AD5662}, 459 {} 460 }; 461 MODULE_DEVICE_TABLE(spi, ad5446_spi_ids); 462 463 static int ad5446_spi_probe(struct spi_device *spi) 464 { 465 const struct spi_device_id *id = spi_get_device_id(spi); 466 467 return ad5446_probe(&spi->dev, id->name, 468 &ad5446_spi_chip_info[id->driver_data]); 469 } 470 471 static int ad5446_spi_remove(struct spi_device *spi) 472 { 473 return ad5446_remove(&spi->dev); 474 } 475 476 static struct spi_driver ad5446_spi_driver = { 477 .driver = { 478 .name = "ad5446", 479 .owner = THIS_MODULE, 480 }, 481 .probe = ad5446_spi_probe, 482 .remove = ad5446_spi_remove, 483 .id_table = ad5446_spi_ids, 484 }; 485 486 static int __init ad5446_spi_register_driver(void) 487 { 488 return spi_register_driver(&ad5446_spi_driver); 489 } 490 491 static void ad5446_spi_unregister_driver(void) 492 { 493 spi_unregister_driver(&ad5446_spi_driver); 494 } 495 496 #else 497 498 static inline int ad5446_spi_register_driver(void) { return 0; } 499 static inline void ad5446_spi_unregister_driver(void) { } 500 501 #endif 502 503 #if IS_ENABLED(CONFIG_I2C) 504 505 static int ad5622_write(struct ad5446_state *st, unsigned val) 506 { 507 struct i2c_client *client = to_i2c_client(st->dev); 508 __be16 data = cpu_to_be16(val); 509 510 return i2c_master_send(client, (char *)&data, sizeof(data)); 511 } 512 513 /** 514 * ad5446_supported_i2c_device_ids: 515 * The AD5620/40/60 parts are available in different fixed internal reference 516 * voltage options. The actual part numbers may look differently 517 * (and a bit cryptic), however this style is used to make clear which 518 * parts are supported here. 519 */ 520 enum ad5446_supported_i2c_device_ids { 521 ID_AD5602, 522 ID_AD5612, 523 ID_AD5622, 524 }; 525 526 static const struct ad5446_chip_info ad5446_i2c_chip_info[] = { 527 [ID_AD5602] = { 528 .channel = AD5446_CHANNEL_POWERDOWN(8, 16, 4), 529 .write = ad5622_write, 530 }, 531 [ID_AD5612] = { 532 .channel = AD5446_CHANNEL_POWERDOWN(10, 16, 2), 533 .write = ad5622_write, 534 }, 535 [ID_AD5622] = { 536 .channel = AD5446_CHANNEL_POWERDOWN(12, 16, 0), 537 .write = ad5622_write, 538 }, 539 }; 540 541 static int ad5446_i2c_probe(struct i2c_client *i2c, 542 const struct i2c_device_id *id) 543 { 544 return ad5446_probe(&i2c->dev, id->name, 545 &ad5446_i2c_chip_info[id->driver_data]); 546 } 547 548 static int ad5446_i2c_remove(struct i2c_client *i2c) 549 { 550 return ad5446_remove(&i2c->dev); 551 } 552 553 static const struct i2c_device_id ad5446_i2c_ids[] = { 554 {"ad5301", ID_AD5602}, 555 {"ad5311", ID_AD5612}, 556 {"ad5321", ID_AD5622}, 557 {"ad5602", ID_AD5602}, 558 {"ad5612", ID_AD5612}, 559 {"ad5622", ID_AD5622}, 560 {} 561 }; 562 MODULE_DEVICE_TABLE(i2c, ad5446_i2c_ids); 563 564 static struct i2c_driver ad5446_i2c_driver = { 565 .driver = { 566 .name = "ad5446", 567 .owner = THIS_MODULE, 568 }, 569 .probe = ad5446_i2c_probe, 570 .remove = ad5446_i2c_remove, 571 .id_table = ad5446_i2c_ids, 572 }; 573 574 static int __init ad5446_i2c_register_driver(void) 575 { 576 return i2c_add_driver(&ad5446_i2c_driver); 577 } 578 579 static void __exit ad5446_i2c_unregister_driver(void) 580 { 581 i2c_del_driver(&ad5446_i2c_driver); 582 } 583 584 #else 585 586 static inline int ad5446_i2c_register_driver(void) { return 0; } 587 static inline void ad5446_i2c_unregister_driver(void) { } 588 589 #endif 590 591 static int __init ad5446_init(void) 592 { 593 int ret; 594 595 ret = ad5446_spi_register_driver(); 596 if (ret) 597 return ret; 598 599 ret = ad5446_i2c_register_driver(); 600 if (ret) { 601 ad5446_spi_unregister_driver(); 602 return ret; 603 } 604 605 return 0; 606 } 607 module_init(ad5446_init); 608 609 static void __exit ad5446_exit(void) 610 { 611 ad5446_i2c_unregister_driver(); 612 ad5446_spi_unregister_driver(); 613 } 614 module_exit(ad5446_exit); 615 616 MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>"); 617 MODULE_DESCRIPTION("Analog Devices AD5444/AD5446 DAC"); 618 MODULE_LICENSE("GPL v2"); 619