1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * INA3221 Triple Current/Voltage Monitor 4 * 5 * Copyright (C) 2016 Texas Instruments Incorporated - https://www.ti.com/ 6 * Andrew F. Davis <afd@ti.com> 7 */ 8 9 #include <linux/hwmon.h> 10 #include <linux/hwmon-sysfs.h> 11 #include <linux/i2c.h> 12 #include <linux/module.h> 13 #include <linux/mutex.h> 14 #include <linux/of.h> 15 #include <linux/pm_runtime.h> 16 #include <linux/regmap.h> 17 #include <linux/util_macros.h> 18 19 #define INA3221_DRIVER_NAME "ina3221" 20 21 #define INA3221_CONFIG 0x00 22 #define INA3221_SHUNT1 0x01 23 #define INA3221_BUS1 0x02 24 #define INA3221_SHUNT2 0x03 25 #define INA3221_BUS2 0x04 26 #define INA3221_SHUNT3 0x05 27 #define INA3221_BUS3 0x06 28 #define INA3221_CRIT1 0x07 29 #define INA3221_WARN1 0x08 30 #define INA3221_CRIT2 0x09 31 #define INA3221_WARN2 0x0a 32 #define INA3221_CRIT3 0x0b 33 #define INA3221_WARN3 0x0c 34 #define INA3221_SHUNT_SUM 0x0d 35 #define INA3221_CRIT_SUM 0x0e 36 #define INA3221_MASK_ENABLE 0x0f 37 38 #define INA3221_CONFIG_MODE_MASK GENMASK(2, 0) 39 #define INA3221_CONFIG_MODE_POWERDOWN 0 40 #define INA3221_CONFIG_MODE_SHUNT BIT(0) 41 #define INA3221_CONFIG_MODE_BUS BIT(1) 42 #define INA3221_CONFIG_MODE_CONTINUOUS BIT(2) 43 #define INA3221_CONFIG_VSH_CT_SHIFT 3 44 #define INA3221_CONFIG_VSH_CT_MASK GENMASK(5, 3) 45 #define INA3221_CONFIG_VSH_CT(x) (((x) & GENMASK(5, 3)) >> 3) 46 #define INA3221_CONFIG_VBUS_CT_SHIFT 6 47 #define INA3221_CONFIG_VBUS_CT_MASK GENMASK(8, 6) 48 #define INA3221_CONFIG_VBUS_CT(x) (((x) & GENMASK(8, 6)) >> 6) 49 #define INA3221_CONFIG_AVG_SHIFT 9 50 #define INA3221_CONFIG_AVG_MASK GENMASK(11, 9) 51 #define INA3221_CONFIG_AVG(x) (((x) & GENMASK(11, 9)) >> 9) 52 #define INA3221_CONFIG_CHs_EN_MASK GENMASK(14, 12) 53 #define INA3221_CONFIG_CHx_EN(x) BIT(14 - (x)) 54 55 #define INA3221_MASK_ENABLE_SCC_MASK GENMASK(14, 12) 56 57 #define INA3221_CONFIG_DEFAULT 0x7127 58 #define INA3221_RSHUNT_DEFAULT 10000 59 60 enum ina3221_fields { 61 /* Configuration */ 62 F_RST, 63 64 /* Status Flags */ 65 F_CVRF, 66 67 /* Warning Flags */ 68 F_WF3, F_WF2, F_WF1, 69 70 /* Alert Flags: SF is the summation-alert flag */ 71 F_SF, F_CF3, F_CF2, F_CF1, 72 73 /* sentinel */ 74 F_MAX_FIELDS 75 }; 76 77 static const struct reg_field ina3221_reg_fields[] = { 78 [F_RST] = REG_FIELD(INA3221_CONFIG, 15, 15), 79 80 [F_CVRF] = REG_FIELD(INA3221_MASK_ENABLE, 0, 0), 81 [F_WF3] = REG_FIELD(INA3221_MASK_ENABLE, 3, 3), 82 [F_WF2] = REG_FIELD(INA3221_MASK_ENABLE, 4, 4), 83 [F_WF1] = REG_FIELD(INA3221_MASK_ENABLE, 5, 5), 84 [F_SF] = REG_FIELD(INA3221_MASK_ENABLE, 6, 6), 85 [F_CF3] = REG_FIELD(INA3221_MASK_ENABLE, 7, 7), 86 [F_CF2] = REG_FIELD(INA3221_MASK_ENABLE, 8, 8), 87 [F_CF1] = REG_FIELD(INA3221_MASK_ENABLE, 9, 9), 88 }; 89 90 enum ina3221_channels { 91 INA3221_CHANNEL1, 92 INA3221_CHANNEL2, 93 INA3221_CHANNEL3, 94 INA3221_NUM_CHANNELS 95 }; 96 97 /** 98 * struct ina3221_input - channel input source specific information 99 * @label: label of channel input source 100 * @shunt_resistor: shunt resistor value of channel input source 101 * @disconnected: connection status of channel input source 102 */ 103 struct ina3221_input { 104 const char *label; 105 int shunt_resistor; 106 bool disconnected; 107 }; 108 109 /** 110 * struct ina3221_data - device specific information 111 * @pm_dev: Device pointer for pm runtime 112 * @regmap: Register map of the device 113 * @fields: Register fields of the device 114 * @inputs: Array of channel input source specific structures 115 * @lock: mutex lock to serialize sysfs attribute accesses 116 * @reg_config: Register value of INA3221_CONFIG 117 * @summation_shunt_resistor: equivalent shunt resistor value for summation 118 * @single_shot: running in single-shot operating mode 119 */ 120 struct ina3221_data { 121 struct device *pm_dev; 122 struct regmap *regmap; 123 struct regmap_field *fields[F_MAX_FIELDS]; 124 struct ina3221_input inputs[INA3221_NUM_CHANNELS]; 125 struct mutex lock; 126 u32 reg_config; 127 int summation_shunt_resistor; 128 129 bool single_shot; 130 }; 131 132 static inline bool ina3221_is_enabled(struct ina3221_data *ina, int channel) 133 { 134 /* Summation channel checks shunt resistor values */ 135 if (channel > INA3221_CHANNEL3) 136 return ina->summation_shunt_resistor != 0; 137 138 return pm_runtime_active(ina->pm_dev) && 139 (ina->reg_config & INA3221_CONFIG_CHx_EN(channel)); 140 } 141 142 /* 143 * Helper function to return the resistor value for current summation. 144 * 145 * There is a condition to calculate current summation -- all the shunt 146 * resistor values should be the same, so as to simply fit the formula: 147 * current summation = shunt voltage summation / shunt resistor 148 * 149 * Returns the equivalent shunt resistor value on success or 0 on failure 150 */ 151 static inline int ina3221_summation_shunt_resistor(struct ina3221_data *ina) 152 { 153 struct ina3221_input *input = ina->inputs; 154 int i, shunt_resistor = 0; 155 156 for (i = 0; i < INA3221_NUM_CHANNELS; i++) { 157 if (input[i].disconnected || !input[i].shunt_resistor) 158 continue; 159 if (!shunt_resistor) { 160 /* Found the reference shunt resistor value */ 161 shunt_resistor = input[i].shunt_resistor; 162 } else { 163 /* No summation if resistor values are different */ 164 if (shunt_resistor != input[i].shunt_resistor) 165 return 0; 166 } 167 } 168 169 return shunt_resistor; 170 } 171 172 /* Lookup table for Bus and Shunt conversion times in usec */ 173 static const u16 ina3221_conv_time[] = { 174 140, 204, 332, 588, 1100, 2116, 4156, 8244, 175 }; 176 177 /* Lookup table for number of samples using in averaging mode */ 178 static const int ina3221_avg_samples[] = { 179 1, 4, 16, 64, 128, 256, 512, 1024, 180 }; 181 182 /* Converting update_interval in msec to conversion time in usec */ 183 static inline u32 ina3221_interval_ms_to_conv_time(u16 config, int interval) 184 { 185 u32 channels = hweight16(config & INA3221_CONFIG_CHs_EN_MASK); 186 u32 samples_idx = INA3221_CONFIG_AVG(config); 187 u32 samples = ina3221_avg_samples[samples_idx]; 188 189 /* Bisect the result to Bus and Shunt conversion times */ 190 return DIV_ROUND_CLOSEST(interval * 1000 / 2, channels * samples); 191 } 192 193 /* Converting CONFIG register value to update_interval in usec */ 194 static inline u32 ina3221_reg_to_interval_us(u16 config) 195 { 196 u32 channels = hweight16(config & INA3221_CONFIG_CHs_EN_MASK); 197 u32 vbus_ct_idx = INA3221_CONFIG_VBUS_CT(config); 198 u32 vsh_ct_idx = INA3221_CONFIG_VSH_CT(config); 199 u32 vbus_ct = ina3221_conv_time[vbus_ct_idx]; 200 u32 vsh_ct = ina3221_conv_time[vsh_ct_idx]; 201 202 /* Calculate total conversion time */ 203 return channels * (vbus_ct + vsh_ct); 204 } 205 206 static inline int ina3221_wait_for_data(struct ina3221_data *ina) 207 { 208 u32 wait, cvrf; 209 210 wait = ina3221_reg_to_interval_us(ina->reg_config); 211 212 /* Polling the CVRF bit to make sure read data is ready */ 213 return regmap_field_read_poll_timeout(ina->fields[F_CVRF], 214 cvrf, cvrf, wait, wait * 2); 215 } 216 217 static int ina3221_read_value(struct ina3221_data *ina, unsigned int reg, 218 int *val) 219 { 220 unsigned int regval; 221 int ret; 222 223 ret = regmap_read(ina->regmap, reg, ®val); 224 if (ret) 225 return ret; 226 227 /* 228 * Shunt Voltage Sum register has 14-bit value with 1-bit shift 229 * Other Shunt Voltage registers have 12 bits with 3-bit shift 230 */ 231 if (reg == INA3221_SHUNT_SUM || reg == INA3221_CRIT_SUM) 232 *val = sign_extend32(regval >> 1, 14); 233 else 234 *val = sign_extend32(regval >> 3, 12); 235 236 return 0; 237 } 238 239 static const u8 ina3221_in_reg[] = { 240 INA3221_BUS1, 241 INA3221_BUS2, 242 INA3221_BUS3, 243 INA3221_SHUNT1, 244 INA3221_SHUNT2, 245 INA3221_SHUNT3, 246 INA3221_SHUNT_SUM, 247 }; 248 249 static int ina3221_read_chip(struct device *dev, u32 attr, long *val) 250 { 251 struct ina3221_data *ina = dev_get_drvdata(dev); 252 int regval; 253 254 switch (attr) { 255 case hwmon_chip_samples: 256 regval = INA3221_CONFIG_AVG(ina->reg_config); 257 *val = ina3221_avg_samples[regval]; 258 return 0; 259 case hwmon_chip_update_interval: 260 /* Return in msec */ 261 *val = ina3221_reg_to_interval_us(ina->reg_config); 262 *val = DIV_ROUND_CLOSEST(*val, 1000); 263 return 0; 264 default: 265 return -EOPNOTSUPP; 266 } 267 } 268 269 static int ina3221_read_in(struct device *dev, u32 attr, int channel, long *val) 270 { 271 const bool is_shunt = channel > INA3221_CHANNEL3; 272 struct ina3221_data *ina = dev_get_drvdata(dev); 273 u8 reg = ina3221_in_reg[channel]; 274 int regval, ret; 275 276 /* 277 * Translate shunt channel index to sensor channel index except 278 * the 7th channel (6 since being 0-aligned) is for summation. 279 */ 280 if (channel != 6) 281 channel %= INA3221_NUM_CHANNELS; 282 283 switch (attr) { 284 case hwmon_in_input: 285 if (!ina3221_is_enabled(ina, channel)) 286 return -ENODATA; 287 288 /* Write CONFIG register to trigger a single-shot measurement */ 289 if (ina->single_shot) { 290 regmap_write(ina->regmap, INA3221_CONFIG, 291 ina->reg_config); 292 293 ret = ina3221_wait_for_data(ina); 294 if (ret) 295 return ret; 296 } 297 298 ret = ina3221_read_value(ina, reg, ®val); 299 if (ret) 300 return ret; 301 302 /* 303 * Scale of shunt voltage (uV): LSB is 40uV 304 * Scale of bus voltage (mV): LSB is 8mV 305 */ 306 *val = regval * (is_shunt ? 40 : 8); 307 return 0; 308 case hwmon_in_enable: 309 *val = ina3221_is_enabled(ina, channel); 310 return 0; 311 default: 312 return -EOPNOTSUPP; 313 } 314 } 315 316 static const u8 ina3221_curr_reg[][INA3221_NUM_CHANNELS + 1] = { 317 [hwmon_curr_input] = { INA3221_SHUNT1, INA3221_SHUNT2, 318 INA3221_SHUNT3, INA3221_SHUNT_SUM }, 319 [hwmon_curr_max] = { INA3221_WARN1, INA3221_WARN2, INA3221_WARN3, 0 }, 320 [hwmon_curr_crit] = { INA3221_CRIT1, INA3221_CRIT2, 321 INA3221_CRIT3, INA3221_CRIT_SUM }, 322 [hwmon_curr_max_alarm] = { F_WF1, F_WF2, F_WF3, 0 }, 323 [hwmon_curr_crit_alarm] = { F_CF1, F_CF2, F_CF3, F_SF }, 324 }; 325 326 static int ina3221_read_curr(struct device *dev, u32 attr, 327 int channel, long *val) 328 { 329 struct ina3221_data *ina = dev_get_drvdata(dev); 330 struct ina3221_input *input = ina->inputs; 331 u8 reg = ina3221_curr_reg[attr][channel]; 332 int resistance_uo, voltage_nv; 333 int regval, ret; 334 335 if (channel > INA3221_CHANNEL3) 336 resistance_uo = ina->summation_shunt_resistor; 337 else 338 resistance_uo = input[channel].shunt_resistor; 339 340 switch (attr) { 341 case hwmon_curr_input: 342 if (!ina3221_is_enabled(ina, channel)) 343 return -ENODATA; 344 345 /* Write CONFIG register to trigger a single-shot measurement */ 346 if (ina->single_shot) { 347 regmap_write(ina->regmap, INA3221_CONFIG, 348 ina->reg_config); 349 350 ret = ina3221_wait_for_data(ina); 351 if (ret) 352 return ret; 353 } 354 355 fallthrough; 356 case hwmon_curr_crit: 357 case hwmon_curr_max: 358 if (!resistance_uo) 359 return -ENODATA; 360 361 ret = ina3221_read_value(ina, reg, ®val); 362 if (ret) 363 return ret; 364 365 /* Scale of shunt voltage: LSB is 40uV (40000nV) */ 366 voltage_nv = regval * 40000; 367 /* Return current in mA */ 368 *val = DIV_ROUND_CLOSEST(voltage_nv, resistance_uo); 369 return 0; 370 case hwmon_curr_crit_alarm: 371 case hwmon_curr_max_alarm: 372 /* No actual register read if channel is disabled */ 373 if (!ina3221_is_enabled(ina, channel)) { 374 /* Return 0 for alert flags */ 375 *val = 0; 376 return 0; 377 } 378 ret = regmap_field_read(ina->fields[reg], ®val); 379 if (ret) 380 return ret; 381 *val = regval; 382 return 0; 383 default: 384 return -EOPNOTSUPP; 385 } 386 } 387 388 static int ina3221_write_chip(struct device *dev, u32 attr, long val) 389 { 390 struct ina3221_data *ina = dev_get_drvdata(dev); 391 int ret, idx; 392 u32 tmp; 393 394 switch (attr) { 395 case hwmon_chip_samples: 396 idx = find_closest(val, ina3221_avg_samples, 397 ARRAY_SIZE(ina3221_avg_samples)); 398 399 tmp = (ina->reg_config & ~INA3221_CONFIG_AVG_MASK) | 400 (idx << INA3221_CONFIG_AVG_SHIFT); 401 ret = regmap_write(ina->regmap, INA3221_CONFIG, tmp); 402 if (ret) 403 return ret; 404 405 /* Update reg_config accordingly */ 406 ina->reg_config = tmp; 407 return 0; 408 case hwmon_chip_update_interval: 409 tmp = ina3221_interval_ms_to_conv_time(ina->reg_config, val); 410 idx = find_closest(tmp, ina3221_conv_time, 411 ARRAY_SIZE(ina3221_conv_time)); 412 413 /* Update Bus and Shunt voltage conversion times */ 414 tmp = INA3221_CONFIG_VBUS_CT_MASK | INA3221_CONFIG_VSH_CT_MASK; 415 tmp = (ina->reg_config & ~tmp) | 416 (idx << INA3221_CONFIG_VBUS_CT_SHIFT) | 417 (idx << INA3221_CONFIG_VSH_CT_SHIFT); 418 ret = regmap_write(ina->regmap, INA3221_CONFIG, tmp); 419 if (ret) 420 return ret; 421 422 /* Update reg_config accordingly */ 423 ina->reg_config = tmp; 424 return 0; 425 default: 426 return -EOPNOTSUPP; 427 } 428 } 429 430 static int ina3221_write_curr(struct device *dev, u32 attr, 431 int channel, long val) 432 { 433 struct ina3221_data *ina = dev_get_drvdata(dev); 434 struct ina3221_input *input = ina->inputs; 435 u8 reg = ina3221_curr_reg[attr][channel]; 436 int resistance_uo, current_ma, voltage_uv; 437 int regval; 438 439 if (channel > INA3221_CHANNEL3) 440 resistance_uo = ina->summation_shunt_resistor; 441 else 442 resistance_uo = input[channel].shunt_resistor; 443 444 if (!resistance_uo) 445 return -EOPNOTSUPP; 446 447 /* clamp current */ 448 current_ma = clamp_val(val, 449 INT_MIN / resistance_uo, 450 INT_MAX / resistance_uo); 451 452 voltage_uv = DIV_ROUND_CLOSEST(current_ma * resistance_uo, 1000); 453 454 /* clamp voltage */ 455 voltage_uv = clamp_val(voltage_uv, -163800, 163800); 456 457 /* 458 * Formula to convert voltage_uv to register value: 459 * regval = (voltage_uv / scale) << shift 460 * Note: 461 * The scale is 40uV for all shunt voltage registers 462 * Shunt Voltage Sum register left-shifts 1 bit 463 * All other Shunt Voltage registers shift 3 bits 464 * Results: 465 * SHUNT_SUM: (1 / 40uV) << 1 = 1 / 20uV 466 * SHUNT[1-3]: (1 / 40uV) << 3 = 1 / 5uV 467 */ 468 if (reg == INA3221_SHUNT_SUM || reg == INA3221_CRIT_SUM) 469 regval = DIV_ROUND_CLOSEST(voltage_uv, 20) & 0xfffe; 470 else 471 regval = DIV_ROUND_CLOSEST(voltage_uv, 5) & 0xfff8; 472 473 return regmap_write(ina->regmap, reg, regval); 474 } 475 476 static int ina3221_write_enable(struct device *dev, int channel, bool enable) 477 { 478 struct ina3221_data *ina = dev_get_drvdata(dev); 479 u16 config, mask = INA3221_CONFIG_CHx_EN(channel); 480 u16 config_old = ina->reg_config & mask; 481 u32 tmp; 482 int ret; 483 484 config = enable ? mask : 0; 485 486 /* Bypass if enable status is not being changed */ 487 if (config_old == config) 488 return 0; 489 490 /* For enabling routine, increase refcount and resume() at first */ 491 if (enable) { 492 ret = pm_runtime_resume_and_get(ina->pm_dev); 493 if (ret < 0) { 494 dev_err(dev, "Failed to get PM runtime\n"); 495 return ret; 496 } 497 } 498 499 /* Enable or disable the channel */ 500 tmp = (ina->reg_config & ~mask) | (config & mask); 501 ret = regmap_write(ina->regmap, INA3221_CONFIG, tmp); 502 if (ret) 503 goto fail; 504 505 /* Cache the latest config register value */ 506 ina->reg_config = tmp; 507 508 /* For disabling routine, decrease refcount or suspend() at last */ 509 if (!enable) 510 pm_runtime_put_sync(ina->pm_dev); 511 512 return 0; 513 514 fail: 515 if (enable) { 516 dev_err(dev, "Failed to enable channel %d: error %d\n", 517 channel, ret); 518 pm_runtime_put_sync(ina->pm_dev); 519 } 520 521 return ret; 522 } 523 524 static int ina3221_read(struct device *dev, enum hwmon_sensor_types type, 525 u32 attr, int channel, long *val) 526 { 527 struct ina3221_data *ina = dev_get_drvdata(dev); 528 int ret; 529 530 mutex_lock(&ina->lock); 531 532 switch (type) { 533 case hwmon_chip: 534 ret = ina3221_read_chip(dev, attr, val); 535 break; 536 case hwmon_in: 537 /* 0-align channel ID */ 538 ret = ina3221_read_in(dev, attr, channel - 1, val); 539 break; 540 case hwmon_curr: 541 ret = ina3221_read_curr(dev, attr, channel, val); 542 break; 543 default: 544 ret = -EOPNOTSUPP; 545 break; 546 } 547 548 mutex_unlock(&ina->lock); 549 550 return ret; 551 } 552 553 static int ina3221_write(struct device *dev, enum hwmon_sensor_types type, 554 u32 attr, int channel, long val) 555 { 556 struct ina3221_data *ina = dev_get_drvdata(dev); 557 int ret; 558 559 mutex_lock(&ina->lock); 560 561 switch (type) { 562 case hwmon_chip: 563 ret = ina3221_write_chip(dev, attr, val); 564 break; 565 case hwmon_in: 566 /* 0-align channel ID */ 567 ret = ina3221_write_enable(dev, channel - 1, val); 568 break; 569 case hwmon_curr: 570 ret = ina3221_write_curr(dev, attr, channel, val); 571 break; 572 default: 573 ret = -EOPNOTSUPP; 574 break; 575 } 576 577 mutex_unlock(&ina->lock); 578 579 return ret; 580 } 581 582 static int ina3221_read_string(struct device *dev, enum hwmon_sensor_types type, 583 u32 attr, int channel, const char **str) 584 { 585 struct ina3221_data *ina = dev_get_drvdata(dev); 586 int index = channel - 1; 587 588 if (channel == 7) 589 *str = "sum of shunt voltages"; 590 else 591 *str = ina->inputs[index].label; 592 593 return 0; 594 } 595 596 static umode_t ina3221_is_visible(const void *drvdata, 597 enum hwmon_sensor_types type, 598 u32 attr, int channel) 599 { 600 const struct ina3221_data *ina = drvdata; 601 const struct ina3221_input *input = NULL; 602 603 switch (type) { 604 case hwmon_chip: 605 switch (attr) { 606 case hwmon_chip_samples: 607 case hwmon_chip_update_interval: 608 return 0644; 609 default: 610 return 0; 611 } 612 case hwmon_in: 613 /* Ignore in0_ */ 614 if (channel == 0) 615 return 0; 616 617 switch (attr) { 618 case hwmon_in_label: 619 if (channel - 1 <= INA3221_CHANNEL3) 620 input = &ina->inputs[channel - 1]; 621 else if (channel == 7) 622 return 0444; 623 /* Hide label node if label is not provided */ 624 return (input && input->label) ? 0444 : 0; 625 case hwmon_in_input: 626 return 0444; 627 case hwmon_in_enable: 628 return 0644; 629 default: 630 return 0; 631 } 632 case hwmon_curr: 633 switch (attr) { 634 case hwmon_curr_input: 635 case hwmon_curr_crit_alarm: 636 case hwmon_curr_max_alarm: 637 return 0444; 638 case hwmon_curr_crit: 639 case hwmon_curr_max: 640 return 0644; 641 default: 642 return 0; 643 } 644 default: 645 return 0; 646 } 647 } 648 649 #define INA3221_HWMON_CURR_CONFIG (HWMON_C_INPUT | \ 650 HWMON_C_CRIT | HWMON_C_CRIT_ALARM | \ 651 HWMON_C_MAX | HWMON_C_MAX_ALARM) 652 653 static const struct hwmon_channel_info *ina3221_info[] = { 654 HWMON_CHANNEL_INFO(chip, 655 HWMON_C_SAMPLES, 656 HWMON_C_UPDATE_INTERVAL), 657 HWMON_CHANNEL_INFO(in, 658 /* 0: dummy, skipped in is_visible */ 659 HWMON_I_INPUT, 660 /* 1-3: input voltage Channels */ 661 HWMON_I_INPUT | HWMON_I_ENABLE | HWMON_I_LABEL, 662 HWMON_I_INPUT | HWMON_I_ENABLE | HWMON_I_LABEL, 663 HWMON_I_INPUT | HWMON_I_ENABLE | HWMON_I_LABEL, 664 /* 4-6: shunt voltage Channels */ 665 HWMON_I_INPUT, 666 HWMON_I_INPUT, 667 HWMON_I_INPUT, 668 /* 7: summation of shunt voltage channels */ 669 HWMON_I_INPUT | HWMON_I_LABEL), 670 HWMON_CHANNEL_INFO(curr, 671 /* 1-3: current channels*/ 672 INA3221_HWMON_CURR_CONFIG, 673 INA3221_HWMON_CURR_CONFIG, 674 INA3221_HWMON_CURR_CONFIG, 675 /* 4: summation of current channels */ 676 HWMON_C_INPUT | HWMON_C_CRIT | HWMON_C_CRIT_ALARM), 677 NULL 678 }; 679 680 static const struct hwmon_ops ina3221_hwmon_ops = { 681 .is_visible = ina3221_is_visible, 682 .read_string = ina3221_read_string, 683 .read = ina3221_read, 684 .write = ina3221_write, 685 }; 686 687 static const struct hwmon_chip_info ina3221_chip_info = { 688 .ops = &ina3221_hwmon_ops, 689 .info = ina3221_info, 690 }; 691 692 /* Extra attribute groups */ 693 static ssize_t ina3221_shunt_show(struct device *dev, 694 struct device_attribute *attr, char *buf) 695 { 696 struct sensor_device_attribute *sd_attr = to_sensor_dev_attr(attr); 697 struct ina3221_data *ina = dev_get_drvdata(dev); 698 unsigned int channel = sd_attr->index; 699 struct ina3221_input *input = &ina->inputs[channel]; 700 701 return sysfs_emit(buf, "%d\n", input->shunt_resistor); 702 } 703 704 static ssize_t ina3221_shunt_store(struct device *dev, 705 struct device_attribute *attr, 706 const char *buf, size_t count) 707 { 708 struct sensor_device_attribute *sd_attr = to_sensor_dev_attr(attr); 709 struct ina3221_data *ina = dev_get_drvdata(dev); 710 unsigned int channel = sd_attr->index; 711 struct ina3221_input *input = &ina->inputs[channel]; 712 int val; 713 int ret; 714 715 ret = kstrtoint(buf, 0, &val); 716 if (ret) 717 return ret; 718 719 val = clamp_val(val, 1, INT_MAX); 720 721 input->shunt_resistor = val; 722 723 /* Update summation_shunt_resistor for summation channel */ 724 ina->summation_shunt_resistor = ina3221_summation_shunt_resistor(ina); 725 726 return count; 727 } 728 729 /* shunt resistance */ 730 static SENSOR_DEVICE_ATTR_RW(shunt1_resistor, ina3221_shunt, INA3221_CHANNEL1); 731 static SENSOR_DEVICE_ATTR_RW(shunt2_resistor, ina3221_shunt, INA3221_CHANNEL2); 732 static SENSOR_DEVICE_ATTR_RW(shunt3_resistor, ina3221_shunt, INA3221_CHANNEL3); 733 734 static struct attribute *ina3221_attrs[] = { 735 &sensor_dev_attr_shunt1_resistor.dev_attr.attr, 736 &sensor_dev_attr_shunt2_resistor.dev_attr.attr, 737 &sensor_dev_attr_shunt3_resistor.dev_attr.attr, 738 NULL, 739 }; 740 ATTRIBUTE_GROUPS(ina3221); 741 742 static const struct regmap_range ina3221_yes_ranges[] = { 743 regmap_reg_range(INA3221_CONFIG, INA3221_BUS3), 744 regmap_reg_range(INA3221_SHUNT_SUM, INA3221_SHUNT_SUM), 745 regmap_reg_range(INA3221_MASK_ENABLE, INA3221_MASK_ENABLE), 746 }; 747 748 static const struct regmap_access_table ina3221_volatile_table = { 749 .yes_ranges = ina3221_yes_ranges, 750 .n_yes_ranges = ARRAY_SIZE(ina3221_yes_ranges), 751 }; 752 753 static const struct regmap_config ina3221_regmap_config = { 754 .reg_bits = 8, 755 .val_bits = 16, 756 757 .cache_type = REGCACHE_RBTREE, 758 .volatile_table = &ina3221_volatile_table, 759 }; 760 761 static int ina3221_probe_child_from_dt(struct device *dev, 762 struct device_node *child, 763 struct ina3221_data *ina) 764 { 765 struct ina3221_input *input; 766 u32 val; 767 int ret; 768 769 ret = of_property_read_u32(child, "reg", &val); 770 if (ret) { 771 dev_err(dev, "missing reg property of %pOFn\n", child); 772 return ret; 773 } else if (val > INA3221_CHANNEL3) { 774 dev_err(dev, "invalid reg %d of %pOFn\n", val, child); 775 return -EINVAL; 776 } 777 778 input = &ina->inputs[val]; 779 780 /* Log the disconnected channel input */ 781 if (!of_device_is_available(child)) { 782 input->disconnected = true; 783 return 0; 784 } 785 786 /* Save the connected input label if available */ 787 of_property_read_string(child, "label", &input->label); 788 789 /* Overwrite default shunt resistor value optionally */ 790 if (!of_property_read_u32(child, "shunt-resistor-micro-ohms", &val)) { 791 if (val < 1 || val > INT_MAX) { 792 dev_err(dev, "invalid shunt resistor value %u of %pOFn\n", 793 val, child); 794 return -EINVAL; 795 } 796 input->shunt_resistor = val; 797 } 798 799 return 0; 800 } 801 802 static int ina3221_probe_from_dt(struct device *dev, struct ina3221_data *ina) 803 { 804 const struct device_node *np = dev->of_node; 805 struct device_node *child; 806 int ret; 807 808 /* Compatible with non-DT platforms */ 809 if (!np) 810 return 0; 811 812 ina->single_shot = of_property_read_bool(np, "ti,single-shot"); 813 814 for_each_child_of_node(np, child) { 815 ret = ina3221_probe_child_from_dt(dev, child, ina); 816 if (ret) { 817 of_node_put(child); 818 return ret; 819 } 820 } 821 822 return 0; 823 } 824 825 static int ina3221_probe(struct i2c_client *client) 826 { 827 struct device *dev = &client->dev; 828 struct ina3221_data *ina; 829 struct device *hwmon_dev; 830 int i, ret; 831 832 ina = devm_kzalloc(dev, sizeof(*ina), GFP_KERNEL); 833 if (!ina) 834 return -ENOMEM; 835 836 ina->regmap = devm_regmap_init_i2c(client, &ina3221_regmap_config); 837 if (IS_ERR(ina->regmap)) { 838 dev_err(dev, "Unable to allocate register map\n"); 839 return PTR_ERR(ina->regmap); 840 } 841 842 for (i = 0; i < F_MAX_FIELDS; i++) { 843 ina->fields[i] = devm_regmap_field_alloc(dev, 844 ina->regmap, 845 ina3221_reg_fields[i]); 846 if (IS_ERR(ina->fields[i])) { 847 dev_err(dev, "Unable to allocate regmap fields\n"); 848 return PTR_ERR(ina->fields[i]); 849 } 850 } 851 852 for (i = 0; i < INA3221_NUM_CHANNELS; i++) 853 ina->inputs[i].shunt_resistor = INA3221_RSHUNT_DEFAULT; 854 855 ret = ina3221_probe_from_dt(dev, ina); 856 if (ret) { 857 dev_err(dev, "Unable to probe from device tree\n"); 858 return ret; 859 } 860 861 /* The driver will be reset, so use reset value */ 862 ina->reg_config = INA3221_CONFIG_DEFAULT; 863 864 /* Clear continuous bit to use single-shot mode */ 865 if (ina->single_shot) 866 ina->reg_config &= ~INA3221_CONFIG_MODE_CONTINUOUS; 867 868 /* Disable channels if their inputs are disconnected */ 869 for (i = 0; i < INA3221_NUM_CHANNELS; i++) { 870 if (ina->inputs[i].disconnected) 871 ina->reg_config &= ~INA3221_CONFIG_CHx_EN(i); 872 } 873 874 /* Initialize summation_shunt_resistor for summation channel control */ 875 ina->summation_shunt_resistor = ina3221_summation_shunt_resistor(ina); 876 877 ina->pm_dev = dev; 878 mutex_init(&ina->lock); 879 dev_set_drvdata(dev, ina); 880 881 /* Enable PM runtime -- status is suspended by default */ 882 pm_runtime_enable(ina->pm_dev); 883 884 /* Initialize (resume) the device */ 885 for (i = 0; i < INA3221_NUM_CHANNELS; i++) { 886 if (ina->inputs[i].disconnected) 887 continue; 888 /* Match the refcount with number of enabled channels */ 889 ret = pm_runtime_get_sync(ina->pm_dev); 890 if (ret < 0) 891 goto fail; 892 } 893 894 hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name, ina, 895 &ina3221_chip_info, 896 ina3221_groups); 897 if (IS_ERR(hwmon_dev)) { 898 dev_err(dev, "Unable to register hwmon device\n"); 899 ret = PTR_ERR(hwmon_dev); 900 goto fail; 901 } 902 903 return 0; 904 905 fail: 906 pm_runtime_disable(ina->pm_dev); 907 pm_runtime_set_suspended(ina->pm_dev); 908 /* pm_runtime_put_noidle() will decrease the PM refcount until 0 */ 909 for (i = 0; i < INA3221_NUM_CHANNELS; i++) 910 pm_runtime_put_noidle(ina->pm_dev); 911 mutex_destroy(&ina->lock); 912 913 return ret; 914 } 915 916 static void ina3221_remove(struct i2c_client *client) 917 { 918 struct ina3221_data *ina = dev_get_drvdata(&client->dev); 919 int i; 920 921 pm_runtime_disable(ina->pm_dev); 922 pm_runtime_set_suspended(ina->pm_dev); 923 924 /* pm_runtime_put_noidle() will decrease the PM refcount until 0 */ 925 for (i = 0; i < INA3221_NUM_CHANNELS; i++) 926 pm_runtime_put_noidle(ina->pm_dev); 927 928 mutex_destroy(&ina->lock); 929 } 930 931 static int ina3221_suspend(struct device *dev) 932 { 933 struct ina3221_data *ina = dev_get_drvdata(dev); 934 int ret; 935 936 /* Save config register value and enable cache-only */ 937 ret = regmap_read(ina->regmap, INA3221_CONFIG, &ina->reg_config); 938 if (ret) 939 return ret; 940 941 /* Set to power-down mode for power saving */ 942 ret = regmap_update_bits(ina->regmap, INA3221_CONFIG, 943 INA3221_CONFIG_MODE_MASK, 944 INA3221_CONFIG_MODE_POWERDOWN); 945 if (ret) 946 return ret; 947 948 regcache_cache_only(ina->regmap, true); 949 regcache_mark_dirty(ina->regmap); 950 951 return 0; 952 } 953 954 static int ina3221_resume(struct device *dev) 955 { 956 struct ina3221_data *ina = dev_get_drvdata(dev); 957 int ret; 958 959 regcache_cache_only(ina->regmap, false); 960 961 /* Software reset the chip */ 962 ret = regmap_field_write(ina->fields[F_RST], true); 963 if (ret) { 964 dev_err(dev, "Unable to reset device\n"); 965 return ret; 966 } 967 968 /* Restore cached register values to hardware */ 969 ret = regcache_sync(ina->regmap); 970 if (ret) 971 return ret; 972 973 /* Restore config register value to hardware */ 974 ret = regmap_write(ina->regmap, INA3221_CONFIG, ina->reg_config); 975 if (ret) 976 return ret; 977 978 /* Initialize summation channel control */ 979 if (ina->summation_shunt_resistor) { 980 /* 981 * Take all three channels into summation by default 982 * Shunt measurements of disconnected channels should 983 * be 0, so it does not matter for summation. 984 */ 985 ret = regmap_update_bits(ina->regmap, INA3221_MASK_ENABLE, 986 INA3221_MASK_ENABLE_SCC_MASK, 987 INA3221_MASK_ENABLE_SCC_MASK); 988 if (ret) { 989 dev_err(dev, "Unable to control summation channel\n"); 990 return ret; 991 } 992 } 993 994 return 0; 995 } 996 997 static DEFINE_RUNTIME_DEV_PM_OPS(ina3221_pm, ina3221_suspend, ina3221_resume, 998 NULL); 999 1000 static const struct of_device_id ina3221_of_match_table[] = { 1001 { .compatible = "ti,ina3221", }, 1002 { /* sentinel */ } 1003 }; 1004 MODULE_DEVICE_TABLE(of, ina3221_of_match_table); 1005 1006 static const struct i2c_device_id ina3221_ids[] = { 1007 { "ina3221", 0 }, 1008 { /* sentinel */ } 1009 }; 1010 MODULE_DEVICE_TABLE(i2c, ina3221_ids); 1011 1012 static struct i2c_driver ina3221_i2c_driver = { 1013 .probe_new = ina3221_probe, 1014 .remove = ina3221_remove, 1015 .driver = { 1016 .name = INA3221_DRIVER_NAME, 1017 .of_match_table = ina3221_of_match_table, 1018 .pm = pm_ptr(&ina3221_pm), 1019 }, 1020 .id_table = ina3221_ids, 1021 }; 1022 module_i2c_driver(ina3221_i2c_driver); 1023 1024 MODULE_AUTHOR("Andrew F. Davis <afd@ti.com>"); 1025 MODULE_DESCRIPTION("Texas Instruments INA3221 HWMon Driver"); 1026 MODULE_LICENSE("GPL v2"); 1027