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