1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * AD5758 Digital to analog converters driver 4 * 5 * Copyright 2018 Analog Devices Inc. 6 * 7 * TODO: Currently CRC is not supported in this driver 8 */ 9 #include <linux/bsearch.h> 10 #include <linux/delay.h> 11 #include <linux/kernel.h> 12 #include <linux/module.h> 13 #include <linux/property.h> 14 #include <linux/of.h> 15 #include <linux/of_device.h> 16 #include <linux/spi/spi.h> 17 #include <linux/gpio/consumer.h> 18 19 #include <linux/iio/iio.h> 20 #include <linux/iio/sysfs.h> 21 22 /* AD5758 registers definition */ 23 #define AD5758_NOP 0x00 24 #define AD5758_DAC_INPUT 0x01 25 #define AD5758_DAC_OUTPUT 0x02 26 #define AD5758_CLEAR_CODE 0x03 27 #define AD5758_USER_GAIN 0x04 28 #define AD5758_USER_OFFSET 0x05 29 #define AD5758_DAC_CONFIG 0x06 30 #define AD5758_SW_LDAC 0x07 31 #define AD5758_KEY 0x08 32 #define AD5758_GP_CONFIG1 0x09 33 #define AD5758_GP_CONFIG2 0x0A 34 #define AD5758_DCDC_CONFIG1 0x0B 35 #define AD5758_DCDC_CONFIG2 0x0C 36 #define AD5758_WDT_CONFIG 0x0F 37 #define AD5758_DIGITAL_DIAG_CONFIG 0x10 38 #define AD5758_ADC_CONFIG 0x11 39 #define AD5758_FAULT_PIN_CONFIG 0x12 40 #define AD5758_TWO_STAGE_READBACK_SELECT 0x13 41 #define AD5758_DIGITAL_DIAG_RESULTS 0x14 42 #define AD5758_ANALOG_DIAG_RESULTS 0x15 43 #define AD5758_STATUS 0x16 44 #define AD5758_CHIP_ID 0x17 45 #define AD5758_FREQ_MONITOR 0x18 46 #define AD5758_DEVICE_ID_0 0x19 47 #define AD5758_DEVICE_ID_1 0x1A 48 #define AD5758_DEVICE_ID_2 0x1B 49 #define AD5758_DEVICE_ID_3 0x1C 50 51 /* AD5758_DAC_CONFIG */ 52 #define AD5758_DAC_CONFIG_RANGE_MSK GENMASK(3, 0) 53 #define AD5758_DAC_CONFIG_RANGE_MODE(x) (((x) & 0xF) << 0) 54 #define AD5758_DAC_CONFIG_INT_EN_MSK BIT(5) 55 #define AD5758_DAC_CONFIG_INT_EN_MODE(x) (((x) & 0x1) << 5) 56 #define AD5758_DAC_CONFIG_OUT_EN_MSK BIT(6) 57 #define AD5758_DAC_CONFIG_OUT_EN_MODE(x) (((x) & 0x1) << 6) 58 #define AD5758_DAC_CONFIG_SR_EN_MSK BIT(8) 59 #define AD5758_DAC_CONFIG_SR_EN_MODE(x) (((x) & 0x1) << 8) 60 #define AD5758_DAC_CONFIG_SR_CLOCK_MSK GENMASK(12, 9) 61 #define AD5758_DAC_CONFIG_SR_CLOCK_MODE(x) (((x) & 0xF) << 9) 62 #define AD5758_DAC_CONFIG_SR_STEP_MSK GENMASK(15, 13) 63 #define AD5758_DAC_CONFIG_SR_STEP_MODE(x) (((x) & 0x7) << 13) 64 65 /* AD5758_KEY */ 66 #define AD5758_KEY_CODE_RESET_1 0x15FA 67 #define AD5758_KEY_CODE_RESET_2 0xAF51 68 #define AD5758_KEY_CODE_SINGLE_ADC_CONV 0x1ADC 69 #define AD5758_KEY_CODE_RESET_WDT 0x0D06 70 #define AD5758_KEY_CODE_CALIB_MEM_REFRESH 0xFCBA 71 72 /* AD5758_DCDC_CONFIG1 */ 73 #define AD5758_DCDC_CONFIG1_DCDC_VPROG_MSK GENMASK(4, 0) 74 #define AD5758_DCDC_CONFIG1_DCDC_VPROG_MODE(x) (((x) & 0x1F) << 0) 75 #define AD5758_DCDC_CONFIG1_DCDC_MODE_MSK GENMASK(6, 5) 76 #define AD5758_DCDC_CONFIG1_DCDC_MODE_MODE(x) (((x) & 0x3) << 5) 77 78 /* AD5758_DCDC_CONFIG2 */ 79 #define AD5758_DCDC_CONFIG2_ILIMIT_MSK GENMASK(3, 1) 80 #define AD5758_DCDC_CONFIG2_ILIMIT_MODE(x) (((x) & 0x7) << 1) 81 #define AD5758_DCDC_CONFIG2_INTR_SAT_3WI_MSK BIT(11) 82 #define AD5758_DCDC_CONFIG2_BUSY_3WI_MSK BIT(12) 83 84 /* AD5758_DIGITAL_DIAG_RESULTS */ 85 #define AD5758_CAL_MEM_UNREFRESHED_MSK BIT(15) 86 87 /* AD5758_ADC_CONFIG */ 88 #define AD5758_ADC_CONFIG_PPC_BUF_EN(x) (((x) & 0x1) << 11) 89 #define AD5758_ADC_CONFIG_PPC_BUF_MSK BIT(11) 90 91 #define AD5758_WR_FLAG_MSK(x) (0x80 | ((x) & 0x1F)) 92 93 #define AD5758_FULL_SCALE_MICRO 65535000000ULL 94 95 struct ad5758_range { 96 int reg; 97 int min; 98 int max; 99 }; 100 101 /** 102 * struct ad5758_state - driver instance specific data 103 * @spi: spi_device 104 * @lock: mutex lock 105 * @gpio_reset: gpio descriptor for the reset line 106 * @out_range: struct which stores the output range 107 * @dc_dc_mode: variable which stores the mode of operation 108 * @dc_dc_ilim: variable which stores the dc-to-dc converter current limit 109 * @slew_time: variable which stores the target slew time 110 * @pwr_down: variable which contains whether a channel is powered down or not 111 * @d32: spi transfer buffers 112 */ 113 struct ad5758_state { 114 struct spi_device *spi; 115 struct mutex lock; 116 struct gpio_desc *gpio_reset; 117 struct ad5758_range out_range; 118 unsigned int dc_dc_mode; 119 unsigned int dc_dc_ilim; 120 unsigned int slew_time; 121 bool pwr_down; 122 __be32 d32[3]; 123 }; 124 125 /* 126 * Output ranges corresponding to bits [3:0] from DAC_CONFIG register 127 * 0000: 0 V to 5 V voltage range 128 * 0001: 0 V to 10 V voltage range 129 * 0010: ±5 V voltage range 130 * 0011: ±10 V voltage range 131 * 1000: 0 mA to 20 mA current range 132 * 1001: 0 mA to 24 mA current range 133 * 1010: 4 mA to 20 mA current range 134 * 1011: ±20 mA current range 135 * 1100: ±24 mA current range 136 * 1101: -1 mA to +22 mA current range 137 */ 138 enum ad5758_output_range { 139 AD5758_RANGE_0V_5V, 140 AD5758_RANGE_0V_10V, 141 AD5758_RANGE_PLUSMINUS_5V, 142 AD5758_RANGE_PLUSMINUS_10V, 143 AD5758_RANGE_0mA_20mA = 8, 144 AD5758_RANGE_0mA_24mA, 145 AD5758_RANGE_4mA_24mA, 146 AD5758_RANGE_PLUSMINUS_20mA, 147 AD5758_RANGE_PLUSMINUS_24mA, 148 AD5758_RANGE_MINUS_1mA_PLUS_22mA, 149 }; 150 151 enum ad5758_dc_dc_mode { 152 AD5758_DCDC_MODE_POWER_OFF, 153 AD5758_DCDC_MODE_DPC_CURRENT, 154 AD5758_DCDC_MODE_DPC_VOLTAGE, 155 AD5758_DCDC_MODE_PPC_CURRENT, 156 }; 157 158 static const struct ad5758_range ad5758_voltage_range[] = { 159 { AD5758_RANGE_0V_5V, 0, 5000000 }, 160 { AD5758_RANGE_0V_10V, 0, 10000000 }, 161 { AD5758_RANGE_PLUSMINUS_5V, -5000000, 5000000 }, 162 { AD5758_RANGE_PLUSMINUS_10V, -10000000, 10000000 } 163 }; 164 165 static const struct ad5758_range ad5758_current_range[] = { 166 { AD5758_RANGE_0mA_20mA, 0, 20000}, 167 { AD5758_RANGE_0mA_24mA, 0, 24000 }, 168 { AD5758_RANGE_4mA_24mA, 4, 24000 }, 169 { AD5758_RANGE_PLUSMINUS_20mA, -20000, 20000 }, 170 { AD5758_RANGE_PLUSMINUS_24mA, -24000, 24000 }, 171 { AD5758_RANGE_MINUS_1mA_PLUS_22mA, -1000, 22000 }, 172 }; 173 174 static const int ad5758_sr_clk[16] = { 175 240000, 200000, 150000, 128000, 64000, 32000, 16000, 8000, 4000, 2000, 176 1000, 512, 256, 128, 64, 16 177 }; 178 179 static const int ad5758_sr_step[8] = { 180 4, 12, 64, 120, 256, 500, 1820, 2048 181 }; 182 183 static const int ad5758_dc_dc_ilim[6] = { 184 150000, 200000, 250000, 300000, 350000, 400000 185 }; 186 187 static int ad5758_spi_reg_read(struct ad5758_state *st, unsigned int addr) 188 { 189 struct spi_transfer t[] = { 190 { 191 .tx_buf = &st->d32[0], 192 .len = 4, 193 .cs_change = 1, 194 }, { 195 .tx_buf = &st->d32[1], 196 .rx_buf = &st->d32[2], 197 .len = 4, 198 }, 199 }; 200 int ret; 201 202 st->d32[0] = cpu_to_be32( 203 (AD5758_WR_FLAG_MSK(AD5758_TWO_STAGE_READBACK_SELECT) << 24) | 204 (addr << 8)); 205 st->d32[1] = cpu_to_be32(AD5758_WR_FLAG_MSK(AD5758_NOP) << 24); 206 207 ret = spi_sync_transfer(st->spi, t, ARRAY_SIZE(t)); 208 if (ret < 0) 209 return ret; 210 211 return (be32_to_cpu(st->d32[2]) >> 8) & 0xFFFF; 212 } 213 214 static int ad5758_spi_reg_write(struct ad5758_state *st, 215 unsigned int addr, 216 unsigned int val) 217 { 218 st->d32[0] = cpu_to_be32((AD5758_WR_FLAG_MSK(addr) << 24) | 219 ((val & 0xFFFF) << 8)); 220 221 return spi_write(st->spi, &st->d32[0], sizeof(st->d32[0])); 222 } 223 224 static int ad5758_spi_write_mask(struct ad5758_state *st, 225 unsigned int addr, 226 unsigned long int mask, 227 unsigned int val) 228 { 229 int regval; 230 231 regval = ad5758_spi_reg_read(st, addr); 232 if (regval < 0) 233 return regval; 234 235 regval &= ~mask; 236 regval |= val; 237 238 return ad5758_spi_reg_write(st, addr, regval); 239 } 240 241 static int cmpfunc(const void *a, const void *b) 242 { 243 return *(int *)a - *(int *)b; 244 } 245 246 static int ad5758_find_closest_match(const int *array, 247 unsigned int size, int val) 248 { 249 int i; 250 251 for (i = 0; i < size; i++) { 252 if (val <= array[i]) 253 return i; 254 } 255 256 return size - 1; 257 } 258 259 static int ad5758_wait_for_task_complete(struct ad5758_state *st, 260 unsigned int reg, 261 unsigned int mask) 262 { 263 unsigned int timeout; 264 int ret; 265 266 timeout = 10; 267 do { 268 ret = ad5758_spi_reg_read(st, reg); 269 if (ret < 0) 270 return ret; 271 272 if (!(ret & mask)) 273 return 0; 274 275 usleep_range(100, 1000); 276 } while (--timeout); 277 278 dev_err(&st->spi->dev, 279 "Error reading bit 0x%x in 0x%x register\n", mask, reg); 280 281 return -EIO; 282 } 283 284 static int ad5758_calib_mem_refresh(struct ad5758_state *st) 285 { 286 int ret; 287 288 ret = ad5758_spi_reg_write(st, AD5758_KEY, 289 AD5758_KEY_CODE_CALIB_MEM_REFRESH); 290 if (ret < 0) { 291 dev_err(&st->spi->dev, 292 "Failed to initiate a calibration memory refresh\n"); 293 return ret; 294 } 295 296 /* Wait to allow time for the internal calibrations to complete */ 297 return ad5758_wait_for_task_complete(st, AD5758_DIGITAL_DIAG_RESULTS, 298 AD5758_CAL_MEM_UNREFRESHED_MSK); 299 } 300 301 static int ad5758_soft_reset(struct ad5758_state *st) 302 { 303 int ret; 304 305 ret = ad5758_spi_reg_write(st, AD5758_KEY, AD5758_KEY_CODE_RESET_1); 306 if (ret < 0) 307 return ret; 308 309 ret = ad5758_spi_reg_write(st, AD5758_KEY, AD5758_KEY_CODE_RESET_2); 310 311 /* Perform a software reset and wait at least 100us */ 312 usleep_range(100, 1000); 313 314 return ret; 315 } 316 317 static int ad5758_set_dc_dc_conv_mode(struct ad5758_state *st, 318 enum ad5758_dc_dc_mode mode) 319 { 320 int ret; 321 322 /* 323 * The ENABLE_PPC_BUFFERS bit must be set prior to enabling PPC current 324 * mode. 325 */ 326 if (mode == AD5758_DCDC_MODE_PPC_CURRENT) { 327 ret = ad5758_spi_write_mask(st, AD5758_ADC_CONFIG, 328 AD5758_ADC_CONFIG_PPC_BUF_MSK, 329 AD5758_ADC_CONFIG_PPC_BUF_EN(1)); 330 if (ret < 0) 331 return ret; 332 } 333 334 ret = ad5758_spi_write_mask(st, AD5758_DCDC_CONFIG1, 335 AD5758_DCDC_CONFIG1_DCDC_MODE_MSK, 336 AD5758_DCDC_CONFIG1_DCDC_MODE_MODE(mode)); 337 if (ret < 0) 338 return ret; 339 340 /* 341 * Poll the BUSY_3WI bit in the DCDC_CONFIG2 register until it is 0. 342 * This allows the 3-wire interface communication to complete. 343 */ 344 ret = ad5758_wait_for_task_complete(st, AD5758_DCDC_CONFIG2, 345 AD5758_DCDC_CONFIG2_BUSY_3WI_MSK); 346 if (ret < 0) 347 return ret; 348 349 st->dc_dc_mode = mode; 350 351 return ret; 352 } 353 354 static int ad5758_set_dc_dc_ilim(struct ad5758_state *st, unsigned int ilim) 355 { 356 int ret; 357 358 ret = ad5758_spi_write_mask(st, AD5758_DCDC_CONFIG2, 359 AD5758_DCDC_CONFIG2_ILIMIT_MSK, 360 AD5758_DCDC_CONFIG2_ILIMIT_MODE(ilim)); 361 if (ret < 0) 362 return ret; 363 /* 364 * Poll the BUSY_3WI bit in the DCDC_CONFIG2 register until it is 0. 365 * This allows the 3-wire interface communication to complete. 366 */ 367 return ad5758_wait_for_task_complete(st, AD5758_DCDC_CONFIG2, 368 AD5758_DCDC_CONFIG2_BUSY_3WI_MSK); 369 } 370 371 static int ad5758_slew_rate_set(struct ad5758_state *st, 372 unsigned int sr_clk_idx, 373 unsigned int sr_step_idx) 374 { 375 unsigned int mode; 376 unsigned long int mask; 377 int ret; 378 379 mask = AD5758_DAC_CONFIG_SR_EN_MSK | 380 AD5758_DAC_CONFIG_SR_CLOCK_MSK | 381 AD5758_DAC_CONFIG_SR_STEP_MSK; 382 mode = AD5758_DAC_CONFIG_SR_EN_MODE(1) | 383 AD5758_DAC_CONFIG_SR_STEP_MODE(sr_step_idx) | 384 AD5758_DAC_CONFIG_SR_CLOCK_MODE(sr_clk_idx); 385 386 ret = ad5758_spi_write_mask(st, AD5758_DAC_CONFIG, mask, mode); 387 if (ret < 0) 388 return ret; 389 390 /* Wait to allow time for the internal calibrations to complete */ 391 return ad5758_wait_for_task_complete(st, AD5758_DIGITAL_DIAG_RESULTS, 392 AD5758_CAL_MEM_UNREFRESHED_MSK); 393 } 394 395 static int ad5758_slew_rate_config(struct ad5758_state *st) 396 { 397 unsigned int sr_clk_idx, sr_step_idx; 398 int i, res; 399 s64 diff_new, diff_old; 400 u64 sr_step, calc_slew_time; 401 402 sr_clk_idx = 0; 403 sr_step_idx = 0; 404 diff_old = S64_MAX; 405 /* 406 * The slew time can be determined by using the formula: 407 * Slew Time = (Full Scale Out / (Step Size x Update Clk Freq)) 408 * where Slew time is expressed in microseconds 409 * Given the desired slew time, the following algorithm determines the 410 * best match for the step size and the update clock frequency. 411 */ 412 for (i = 0; i < ARRAY_SIZE(ad5758_sr_clk); i++) { 413 /* 414 * Go through each valid update clock freq and determine a raw 415 * value for the step size by using the formula: 416 * Step Size = Full Scale Out / (Update Clk Freq * Slew Time) 417 */ 418 sr_step = AD5758_FULL_SCALE_MICRO; 419 do_div(sr_step, ad5758_sr_clk[i]); 420 do_div(sr_step, st->slew_time); 421 /* 422 * After a raw value for step size was determined, find the 423 * closest valid match 424 */ 425 res = ad5758_find_closest_match(ad5758_sr_step, 426 ARRAY_SIZE(ad5758_sr_step), 427 sr_step); 428 /* Calculate the slew time */ 429 calc_slew_time = AD5758_FULL_SCALE_MICRO; 430 do_div(calc_slew_time, ad5758_sr_step[res]); 431 do_div(calc_slew_time, ad5758_sr_clk[i]); 432 /* 433 * Determine with how many microseconds the calculated slew time 434 * is different from the desired slew time and store the diff 435 * for the next iteration 436 */ 437 diff_new = abs(st->slew_time - calc_slew_time); 438 if (diff_new < diff_old) { 439 diff_old = diff_new; 440 sr_clk_idx = i; 441 sr_step_idx = res; 442 } 443 } 444 445 return ad5758_slew_rate_set(st, sr_clk_idx, sr_step_idx); 446 } 447 448 static int ad5758_set_out_range(struct ad5758_state *st, int range) 449 { 450 int ret; 451 452 ret = ad5758_spi_write_mask(st, AD5758_DAC_CONFIG, 453 AD5758_DAC_CONFIG_RANGE_MSK, 454 AD5758_DAC_CONFIG_RANGE_MODE(range)); 455 if (ret < 0) 456 return ret; 457 458 /* Wait to allow time for the internal calibrations to complete */ 459 return ad5758_wait_for_task_complete(st, AD5758_DIGITAL_DIAG_RESULTS, 460 AD5758_CAL_MEM_UNREFRESHED_MSK); 461 } 462 463 static int ad5758_internal_buffers_en(struct ad5758_state *st, bool enable) 464 { 465 int ret; 466 467 ret = ad5758_spi_write_mask(st, AD5758_DAC_CONFIG, 468 AD5758_DAC_CONFIG_INT_EN_MSK, 469 AD5758_DAC_CONFIG_INT_EN_MODE(enable)); 470 if (ret < 0) 471 return ret; 472 473 /* Wait to allow time for the internal calibrations to complete */ 474 return ad5758_wait_for_task_complete(st, AD5758_DIGITAL_DIAG_RESULTS, 475 AD5758_CAL_MEM_UNREFRESHED_MSK); 476 } 477 478 static int ad5758_reset(struct ad5758_state *st) 479 { 480 if (st->gpio_reset) { 481 gpiod_set_value(st->gpio_reset, 0); 482 usleep_range(100, 1000); 483 gpiod_set_value(st->gpio_reset, 1); 484 usleep_range(100, 1000); 485 486 return 0; 487 } else { 488 /* Perform a software reset */ 489 return ad5758_soft_reset(st); 490 } 491 } 492 493 static int ad5758_reg_access(struct iio_dev *indio_dev, 494 unsigned int reg, 495 unsigned int writeval, 496 unsigned int *readval) 497 { 498 struct ad5758_state *st = iio_priv(indio_dev); 499 int ret; 500 501 mutex_lock(&st->lock); 502 if (readval) { 503 ret = ad5758_spi_reg_read(st, reg); 504 if (ret < 0) { 505 mutex_unlock(&st->lock); 506 return ret; 507 } 508 509 *readval = ret; 510 ret = 0; 511 } else { 512 ret = ad5758_spi_reg_write(st, reg, writeval); 513 } 514 mutex_unlock(&st->lock); 515 516 return ret; 517 } 518 519 static int ad5758_read_raw(struct iio_dev *indio_dev, 520 struct iio_chan_spec const *chan, 521 int *val, int *val2, long info) 522 { 523 struct ad5758_state *st = iio_priv(indio_dev); 524 int max, min, ret; 525 526 switch (info) { 527 case IIO_CHAN_INFO_RAW: 528 mutex_lock(&st->lock); 529 ret = ad5758_spi_reg_read(st, AD5758_DAC_INPUT); 530 mutex_unlock(&st->lock); 531 if (ret < 0) 532 return ret; 533 534 *val = ret; 535 return IIO_VAL_INT; 536 case IIO_CHAN_INFO_SCALE: 537 min = st->out_range.min; 538 max = st->out_range.max; 539 *val = (max - min) / 1000; 540 *val2 = 16; 541 return IIO_VAL_FRACTIONAL_LOG2; 542 case IIO_CHAN_INFO_OFFSET: 543 min = st->out_range.min; 544 max = st->out_range.max; 545 *val = ((min * (1 << 16)) / (max - min)) / 1000; 546 return IIO_VAL_INT; 547 default: 548 return -EINVAL; 549 } 550 } 551 552 static int ad5758_write_raw(struct iio_dev *indio_dev, 553 struct iio_chan_spec const *chan, 554 int val, int val2, long info) 555 { 556 struct ad5758_state *st = iio_priv(indio_dev); 557 int ret; 558 559 switch (info) { 560 case IIO_CHAN_INFO_RAW: 561 mutex_lock(&st->lock); 562 ret = ad5758_spi_reg_write(st, AD5758_DAC_INPUT, val); 563 mutex_unlock(&st->lock); 564 return ret; 565 default: 566 return -EINVAL; 567 } 568 } 569 570 static ssize_t ad5758_read_powerdown(struct iio_dev *indio_dev, 571 uintptr_t priv, 572 const struct iio_chan_spec *chan, 573 char *buf) 574 { 575 struct ad5758_state *st = iio_priv(indio_dev); 576 577 return sprintf(buf, "%d\n", st->pwr_down); 578 } 579 580 static ssize_t ad5758_write_powerdown(struct iio_dev *indio_dev, 581 uintptr_t priv, 582 struct iio_chan_spec const *chan, 583 const char *buf, size_t len) 584 { 585 struct ad5758_state *st = iio_priv(indio_dev); 586 bool pwr_down; 587 unsigned int dac_config_mode, val; 588 unsigned long int dac_config_msk; 589 int ret; 590 591 ret = kstrtobool(buf, &pwr_down); 592 if (ret) 593 return ret; 594 595 mutex_lock(&st->lock); 596 if (pwr_down) 597 val = 0; 598 else 599 val = 1; 600 601 dac_config_mode = AD5758_DAC_CONFIG_OUT_EN_MODE(val) | 602 AD5758_DAC_CONFIG_INT_EN_MODE(val); 603 dac_config_msk = AD5758_DAC_CONFIG_OUT_EN_MSK | 604 AD5758_DAC_CONFIG_INT_EN_MSK; 605 606 ret = ad5758_spi_write_mask(st, AD5758_DAC_CONFIG, 607 dac_config_msk, 608 dac_config_mode); 609 if (ret < 0) 610 goto err_unlock; 611 612 st->pwr_down = pwr_down; 613 614 err_unlock: 615 mutex_unlock(&st->lock); 616 617 return ret ? ret : len; 618 } 619 620 static const struct iio_info ad5758_info = { 621 .read_raw = ad5758_read_raw, 622 .write_raw = ad5758_write_raw, 623 .debugfs_reg_access = &ad5758_reg_access, 624 }; 625 626 static const struct iio_chan_spec_ext_info ad5758_ext_info[] = { 627 { 628 .name = "powerdown", 629 .read = ad5758_read_powerdown, 630 .write = ad5758_write_powerdown, 631 .shared = IIO_SHARED_BY_TYPE, 632 }, 633 { } 634 }; 635 636 #define AD5758_DAC_CHAN(_chan_type) { \ 637 .type = (_chan_type), \ 638 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_RAW) | \ 639 BIT(IIO_CHAN_INFO_SCALE) | \ 640 BIT(IIO_CHAN_INFO_OFFSET), \ 641 .indexed = 1, \ 642 .output = 1, \ 643 .ext_info = ad5758_ext_info, \ 644 } 645 646 static const struct iio_chan_spec ad5758_voltage_ch[] = { 647 AD5758_DAC_CHAN(IIO_VOLTAGE) 648 }; 649 650 static const struct iio_chan_spec ad5758_current_ch[] = { 651 AD5758_DAC_CHAN(IIO_CURRENT) 652 }; 653 654 static bool ad5758_is_valid_mode(enum ad5758_dc_dc_mode mode) 655 { 656 switch (mode) { 657 case AD5758_DCDC_MODE_DPC_CURRENT: 658 case AD5758_DCDC_MODE_DPC_VOLTAGE: 659 case AD5758_DCDC_MODE_PPC_CURRENT: 660 return true; 661 default: 662 return false; 663 } 664 } 665 666 static int ad5758_crc_disable(struct ad5758_state *st) 667 { 668 unsigned int mask; 669 670 mask = (AD5758_WR_FLAG_MSK(AD5758_DIGITAL_DIAG_CONFIG) << 24) | 0x5C3A; 671 st->d32[0] = cpu_to_be32(mask); 672 673 return spi_write(st->spi, &st->d32[0], 4); 674 } 675 676 static int ad5758_find_out_range(struct ad5758_state *st, 677 const struct ad5758_range *range, 678 unsigned int size, 679 int min, int max) 680 { 681 int i; 682 683 for (i = 0; i < size; i++) { 684 if ((min == range[i].min) && (max == range[i].max)) { 685 st->out_range.reg = range[i].reg; 686 st->out_range.min = range[i].min; 687 st->out_range.max = range[i].max; 688 689 return 0; 690 } 691 } 692 693 return -EINVAL; 694 } 695 696 static int ad5758_parse_dt(struct ad5758_state *st) 697 { 698 unsigned int tmp, tmparray[2], size; 699 const struct ad5758_range *range; 700 int *index, ret; 701 702 st->dc_dc_ilim = 0; 703 ret = device_property_read_u32(&st->spi->dev, 704 "adi,dc-dc-ilim-microamp", &tmp); 705 if (ret) { 706 dev_dbg(&st->spi->dev, 707 "Missing \"dc-dc-ilim-microamp\" property\n"); 708 } else { 709 index = bsearch(&tmp, ad5758_dc_dc_ilim, 710 ARRAY_SIZE(ad5758_dc_dc_ilim), 711 sizeof(int), cmpfunc); 712 if (!index) 713 dev_dbg(&st->spi->dev, "dc-dc-ilim out of range\n"); 714 else 715 st->dc_dc_ilim = index - ad5758_dc_dc_ilim; 716 } 717 718 ret = device_property_read_u32(&st->spi->dev, "adi,dc-dc-mode", 719 &st->dc_dc_mode); 720 if (ret) { 721 dev_err(&st->spi->dev, "Missing \"dc-dc-mode\" property\n"); 722 return ret; 723 } 724 725 if (!ad5758_is_valid_mode(st->dc_dc_mode)) 726 return -EINVAL; 727 728 if (st->dc_dc_mode == AD5758_DCDC_MODE_DPC_VOLTAGE) { 729 ret = device_property_read_u32_array(&st->spi->dev, 730 "adi,range-microvolt", 731 tmparray, 2); 732 if (ret) { 733 dev_err(&st->spi->dev, 734 "Missing \"range-microvolt\" property\n"); 735 return ret; 736 } 737 range = ad5758_voltage_range; 738 size = ARRAY_SIZE(ad5758_voltage_range); 739 } else { 740 ret = device_property_read_u32_array(&st->spi->dev, 741 "adi,range-microamp", 742 tmparray, 2); 743 if (ret) { 744 dev_err(&st->spi->dev, 745 "Missing \"range-microamp\" property\n"); 746 return ret; 747 } 748 range = ad5758_current_range; 749 size = ARRAY_SIZE(ad5758_current_range); 750 } 751 752 ret = ad5758_find_out_range(st, range, size, tmparray[0], tmparray[1]); 753 if (ret) { 754 dev_err(&st->spi->dev, "range invalid\n"); 755 return ret; 756 } 757 758 ret = device_property_read_u32(&st->spi->dev, "adi,slew-time-us", &tmp); 759 if (ret) { 760 dev_dbg(&st->spi->dev, "Missing \"slew-time-us\" property\n"); 761 st->slew_time = 0; 762 } else { 763 st->slew_time = tmp; 764 } 765 766 return 0; 767 } 768 769 static int ad5758_init(struct ad5758_state *st) 770 { 771 int regval, ret; 772 773 st->gpio_reset = devm_gpiod_get_optional(&st->spi->dev, "reset", 774 GPIOD_OUT_HIGH); 775 if (IS_ERR(st->gpio_reset)) 776 return PTR_ERR(st->gpio_reset); 777 778 /* Disable CRC checks */ 779 ret = ad5758_crc_disable(st); 780 if (ret < 0) 781 return ret; 782 783 /* Perform a reset */ 784 ret = ad5758_reset(st); 785 if (ret < 0) 786 return ret; 787 788 /* Disable CRC checks */ 789 ret = ad5758_crc_disable(st); 790 if (ret < 0) 791 return ret; 792 793 /* Perform a calibration memory refresh */ 794 ret = ad5758_calib_mem_refresh(st); 795 if (ret < 0) 796 return ret; 797 798 regval = ad5758_spi_reg_read(st, AD5758_DIGITAL_DIAG_RESULTS); 799 if (regval < 0) 800 return regval; 801 802 /* Clear all the error flags */ 803 ret = ad5758_spi_reg_write(st, AD5758_DIGITAL_DIAG_RESULTS, regval); 804 if (ret < 0) 805 return ret; 806 807 /* Set the dc-to-dc current limit */ 808 ret = ad5758_set_dc_dc_ilim(st, st->dc_dc_ilim); 809 if (ret < 0) 810 return ret; 811 812 /* Configure the dc-to-dc controller mode */ 813 ret = ad5758_set_dc_dc_conv_mode(st, st->dc_dc_mode); 814 if (ret < 0) 815 return ret; 816 817 /* Configure the output range */ 818 ret = ad5758_set_out_range(st, st->out_range.reg); 819 if (ret < 0) 820 return ret; 821 822 /* Enable Slew Rate Control, set the slew rate clock and step */ 823 if (st->slew_time) { 824 ret = ad5758_slew_rate_config(st); 825 if (ret < 0) 826 return ret; 827 } 828 829 /* Power up the DAC and internal (INT) amplifiers */ 830 ret = ad5758_internal_buffers_en(st, 1); 831 if (ret < 0) 832 return ret; 833 834 /* Enable VIOUT */ 835 return ad5758_spi_write_mask(st, AD5758_DAC_CONFIG, 836 AD5758_DAC_CONFIG_OUT_EN_MSK, 837 AD5758_DAC_CONFIG_OUT_EN_MODE(1)); 838 } 839 840 static int ad5758_probe(struct spi_device *spi) 841 { 842 struct ad5758_state *st; 843 struct iio_dev *indio_dev; 844 int ret; 845 846 indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st)); 847 if (!indio_dev) 848 return -ENOMEM; 849 850 st = iio_priv(indio_dev); 851 spi_set_drvdata(spi, indio_dev); 852 853 st->spi = spi; 854 855 mutex_init(&st->lock); 856 857 indio_dev->name = spi_get_device_id(spi)->name; 858 indio_dev->info = &ad5758_info; 859 indio_dev->modes = INDIO_DIRECT_MODE; 860 indio_dev->num_channels = 1; 861 862 ret = ad5758_parse_dt(st); 863 if (ret < 0) 864 return ret; 865 866 if (st->dc_dc_mode == AD5758_DCDC_MODE_DPC_VOLTAGE) 867 indio_dev->channels = ad5758_voltage_ch; 868 else 869 indio_dev->channels = ad5758_current_ch; 870 871 ret = ad5758_init(st); 872 if (ret < 0) { 873 dev_err(&spi->dev, "AD5758 init failed\n"); 874 return ret; 875 } 876 877 return devm_iio_device_register(&st->spi->dev, indio_dev); 878 } 879 880 static const struct spi_device_id ad5758_id[] = { 881 { "ad5758", 0 }, 882 {} 883 }; 884 MODULE_DEVICE_TABLE(spi, ad5758_id); 885 886 static const struct of_device_id ad5758_of_match[] = { 887 { .compatible = "adi,ad5758" }, 888 { }, 889 }; 890 MODULE_DEVICE_TABLE(of, ad5758_of_match); 891 892 static struct spi_driver ad5758_driver = { 893 .driver = { 894 .name = KBUILD_MODNAME, 895 .of_match_table = ad5758_of_match, 896 }, 897 .probe = ad5758_probe, 898 .id_table = ad5758_id, 899 }; 900 901 module_spi_driver(ad5758_driver); 902 903 MODULE_AUTHOR("Stefan Popa <stefan.popa@analog.com>"); 904 MODULE_DESCRIPTION("Analog Devices AD5758 DAC"); 905 MODULE_LICENSE("GPL v2"); 906