1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (c) 2020 Sartura Ltd. 4 * 5 * Driver for the TI TPS23861 PoE PSE. 6 * 7 * Author: Robert Marko <robert.marko@sartura.hr> 8 */ 9 10 #include <linux/bitfield.h> 11 #include <linux/debugfs.h> 12 #include <linux/delay.h> 13 #include <linux/hwmon-sysfs.h> 14 #include <linux/hwmon.h> 15 #include <linux/i2c.h> 16 #include <linux/module.h> 17 #include <linux/of_device.h> 18 #include <linux/regmap.h> 19 20 #define TEMPERATURE 0x2c 21 #define INPUT_VOLTAGE_LSB 0x2e 22 #define INPUT_VOLTAGE_MSB 0x2f 23 #define PORT_1_CURRENT_LSB 0x30 24 #define PORT_1_CURRENT_MSB 0x31 25 #define PORT_1_VOLTAGE_LSB 0x32 26 #define PORT_1_VOLTAGE_MSB 0x33 27 #define PORT_2_CURRENT_LSB 0x34 28 #define PORT_2_CURRENT_MSB 0x35 29 #define PORT_2_VOLTAGE_LSB 0x36 30 #define PORT_2_VOLTAGE_MSB 0x37 31 #define PORT_3_CURRENT_LSB 0x38 32 #define PORT_3_CURRENT_MSB 0x39 33 #define PORT_3_VOLTAGE_LSB 0x3a 34 #define PORT_3_VOLTAGE_MSB 0x3b 35 #define PORT_4_CURRENT_LSB 0x3c 36 #define PORT_4_CURRENT_MSB 0x3d 37 #define PORT_4_VOLTAGE_LSB 0x3e 38 #define PORT_4_VOLTAGE_MSB 0x3f 39 #define PORT_N_CURRENT_LSB_OFFSET 0x04 40 #define PORT_N_VOLTAGE_LSB_OFFSET 0x04 41 #define VOLTAGE_CURRENT_MASK GENMASK(13, 0) 42 #define PORT_1_RESISTANCE_LSB 0x60 43 #define PORT_1_RESISTANCE_MSB 0x61 44 #define PORT_2_RESISTANCE_LSB 0x62 45 #define PORT_2_RESISTANCE_MSB 0x63 46 #define PORT_3_RESISTANCE_LSB 0x64 47 #define PORT_3_RESISTANCE_MSB 0x65 48 #define PORT_4_RESISTANCE_LSB 0x66 49 #define PORT_4_RESISTANCE_MSB 0x67 50 #define PORT_N_RESISTANCE_LSB_OFFSET 0x02 51 #define PORT_RESISTANCE_MASK GENMASK(13, 0) 52 #define PORT_RESISTANCE_RSN_MASK GENMASK(15, 14) 53 #define PORT_RESISTANCE_RSN_OTHER 0 54 #define PORT_RESISTANCE_RSN_LOW 1 55 #define PORT_RESISTANCE_RSN_OPEN 2 56 #define PORT_RESISTANCE_RSN_SHORT 3 57 #define PORT_1_STATUS 0x0c 58 #define PORT_2_STATUS 0x0d 59 #define PORT_3_STATUS 0x0e 60 #define PORT_4_STATUS 0x0f 61 #define PORT_STATUS_CLASS_MASK GENMASK(7, 4) 62 #define PORT_STATUS_DETECT_MASK GENMASK(3, 0) 63 #define PORT_CLASS_UNKNOWN 0 64 #define PORT_CLASS_1 1 65 #define PORT_CLASS_2 2 66 #define PORT_CLASS_3 3 67 #define PORT_CLASS_4 4 68 #define PORT_CLASS_RESERVED 5 69 #define PORT_CLASS_0 6 70 #define PORT_CLASS_OVERCURRENT 7 71 #define PORT_CLASS_MISMATCH 8 72 #define PORT_DETECT_UNKNOWN 0 73 #define PORT_DETECT_SHORT 1 74 #define PORT_DETECT_RESERVED 2 75 #define PORT_DETECT_RESISTANCE_LOW 3 76 #define PORT_DETECT_RESISTANCE_OK 4 77 #define PORT_DETECT_RESISTANCE_HIGH 5 78 #define PORT_DETECT_OPEN_CIRCUIT 6 79 #define PORT_DETECT_RESERVED_2 7 80 #define PORT_DETECT_MOSFET_FAULT 8 81 #define PORT_DETECT_LEGACY 9 82 /* Measurment beyond clamp voltage */ 83 #define PORT_DETECT_CAPACITANCE_INVALID_BEYOND 10 84 /* Insufficient voltage delta */ 85 #define PORT_DETECT_CAPACITANCE_INVALID_DELTA 11 86 #define PORT_DETECT_CAPACITANCE_OUT_OF_RANGE 12 87 #define POE_PLUS 0x40 88 #define OPERATING_MODE 0x12 89 #define OPERATING_MODE_OFF 0 90 #define OPERATING_MODE_MANUAL 1 91 #define OPERATING_MODE_SEMI 2 92 #define OPERATING_MODE_AUTO 3 93 #define OPERATING_MODE_PORT_1_MASK GENMASK(1, 0) 94 #define OPERATING_MODE_PORT_2_MASK GENMASK(3, 2) 95 #define OPERATING_MODE_PORT_3_MASK GENMASK(5, 4) 96 #define OPERATING_MODE_PORT_4_MASK GENMASK(7, 6) 97 98 #define DETECT_CLASS_RESTART 0x18 99 #define POWER_ENABLE 0x19 100 #define TPS23861_NUM_PORTS 4 101 102 #define TPS23861_GENERAL_MASK_1 0x17 103 #define TPS23861_CURRENT_SHUNT_MASK BIT(0) 104 105 #define TEMPERATURE_LSB 652 /* 0.652 degrees Celsius */ 106 #define VOLTAGE_LSB 3662 /* 3.662 mV */ 107 #define SHUNT_RESISTOR_DEFAULT 255000 /* 255 mOhm */ 108 #define CURRENT_LSB_250 62260 /* 62.260 uA */ 109 #define CURRENT_LSB_255 61039 /* 61.039 uA */ 110 #define RESISTANCE_LSB 110966 /* 11.0966 Ohm*/ 111 #define RESISTANCE_LSB_LOW 157216 /* 15.7216 Ohm*/ 112 113 struct tps23861_data { 114 struct regmap *regmap; 115 u32 shunt_resistor; 116 struct i2c_client *client; 117 struct dentry *debugfs_dir; 118 }; 119 120 static struct regmap_config tps23861_regmap_config = { 121 .reg_bits = 8, 122 .val_bits = 8, 123 .max_register = 0x6f, 124 }; 125 126 static int tps23861_read_temp(struct tps23861_data *data, long *val) 127 { 128 unsigned int regval; 129 int err; 130 131 err = regmap_read(data->regmap, TEMPERATURE, ®val); 132 if (err < 0) 133 return err; 134 135 *val = (regval * TEMPERATURE_LSB) - 20000; 136 137 return 0; 138 } 139 140 static int tps23861_read_voltage(struct tps23861_data *data, int channel, 141 long *val) 142 { 143 __le16 regval; 144 long raw_val; 145 int err; 146 147 if (channel < TPS23861_NUM_PORTS) { 148 err = regmap_bulk_read(data->regmap, 149 PORT_1_VOLTAGE_LSB + channel * PORT_N_VOLTAGE_LSB_OFFSET, 150 ®val, 2); 151 } else { 152 err = regmap_bulk_read(data->regmap, 153 INPUT_VOLTAGE_LSB, 154 ®val, 2); 155 } 156 if (err < 0) 157 return err; 158 159 raw_val = le16_to_cpu(regval); 160 *val = (FIELD_GET(VOLTAGE_CURRENT_MASK, raw_val) * VOLTAGE_LSB) / 1000; 161 162 return 0; 163 } 164 165 static int tps23861_read_current(struct tps23861_data *data, int channel, 166 long *val) 167 { 168 long raw_val, current_lsb; 169 __le16 regval; 170 171 int err; 172 173 if (data->shunt_resistor == SHUNT_RESISTOR_DEFAULT) 174 current_lsb = CURRENT_LSB_255; 175 else 176 current_lsb = CURRENT_LSB_250; 177 178 err = regmap_bulk_read(data->regmap, 179 PORT_1_CURRENT_LSB + channel * PORT_N_CURRENT_LSB_OFFSET, 180 ®val, 2); 181 if (err < 0) 182 return err; 183 184 raw_val = le16_to_cpu(regval); 185 *val = (FIELD_GET(VOLTAGE_CURRENT_MASK, raw_val) * current_lsb) / 1000000; 186 187 return 0; 188 } 189 190 static int tps23861_port_disable(struct tps23861_data *data, int channel) 191 { 192 unsigned int regval = 0; 193 int err; 194 195 regval |= BIT(channel + 4); 196 err = regmap_write(data->regmap, POWER_ENABLE, regval); 197 198 return err; 199 } 200 201 static int tps23861_port_enable(struct tps23861_data *data, int channel) 202 { 203 unsigned int regval = 0; 204 int err; 205 206 regval |= BIT(channel); 207 regval |= BIT(channel + 4); 208 err = regmap_write(data->regmap, DETECT_CLASS_RESTART, regval); 209 210 return err; 211 } 212 213 static umode_t tps23861_is_visible(const void *data, enum hwmon_sensor_types type, 214 u32 attr, int channel) 215 { 216 switch (type) { 217 case hwmon_temp: 218 switch (attr) { 219 case hwmon_temp_input: 220 case hwmon_temp_label: 221 return 0444; 222 default: 223 return 0; 224 } 225 case hwmon_in: 226 switch (attr) { 227 case hwmon_in_input: 228 case hwmon_in_label: 229 return 0444; 230 case hwmon_in_enable: 231 return 0200; 232 default: 233 return 0; 234 } 235 case hwmon_curr: 236 switch (attr) { 237 case hwmon_curr_input: 238 case hwmon_curr_label: 239 return 0444; 240 default: 241 return 0; 242 } 243 default: 244 return 0; 245 } 246 } 247 248 static int tps23861_write(struct device *dev, enum hwmon_sensor_types type, 249 u32 attr, int channel, long val) 250 { 251 struct tps23861_data *data = dev_get_drvdata(dev); 252 int err; 253 254 switch (type) { 255 case hwmon_in: 256 switch (attr) { 257 case hwmon_in_enable: 258 if (val == 0) 259 err = tps23861_port_disable(data, channel); 260 else if (val == 1) 261 err = tps23861_port_enable(data, channel); 262 else 263 err = -EINVAL; 264 break; 265 default: 266 return -EOPNOTSUPP; 267 } 268 break; 269 default: 270 return -EOPNOTSUPP; 271 } 272 273 return err; 274 } 275 276 static int tps23861_read(struct device *dev, enum hwmon_sensor_types type, 277 u32 attr, int channel, long *val) 278 { 279 struct tps23861_data *data = dev_get_drvdata(dev); 280 int err; 281 282 switch (type) { 283 case hwmon_temp: 284 switch (attr) { 285 case hwmon_temp_input: 286 err = tps23861_read_temp(data, val); 287 break; 288 default: 289 return -EOPNOTSUPP; 290 } 291 break; 292 case hwmon_in: 293 switch (attr) { 294 case hwmon_in_input: 295 err = tps23861_read_voltage(data, channel, val); 296 break; 297 default: 298 return -EOPNOTSUPP; 299 } 300 break; 301 case hwmon_curr: 302 switch (attr) { 303 case hwmon_curr_input: 304 err = tps23861_read_current(data, channel, val); 305 break; 306 default: 307 return -EOPNOTSUPP; 308 } 309 break; 310 default: 311 return -EOPNOTSUPP; 312 } 313 314 return err; 315 } 316 317 static const char * const tps23861_port_label[] = { 318 "Port1", 319 "Port2", 320 "Port3", 321 "Port4", 322 "Input", 323 }; 324 325 static int tps23861_read_string(struct device *dev, 326 enum hwmon_sensor_types type, 327 u32 attr, int channel, const char **str) 328 { 329 switch (type) { 330 case hwmon_in: 331 case hwmon_curr: 332 *str = tps23861_port_label[channel]; 333 break; 334 case hwmon_temp: 335 *str = "Die"; 336 break; 337 default: 338 return -EOPNOTSUPP; 339 } 340 341 return 0; 342 } 343 344 static const struct hwmon_channel_info *tps23861_info[] = { 345 HWMON_CHANNEL_INFO(chip, 346 HWMON_C_REGISTER_TZ), 347 HWMON_CHANNEL_INFO(temp, 348 HWMON_T_INPUT | HWMON_T_LABEL), 349 HWMON_CHANNEL_INFO(in, 350 HWMON_I_INPUT | HWMON_I_ENABLE | HWMON_I_LABEL, 351 HWMON_I_INPUT | HWMON_I_ENABLE | HWMON_I_LABEL, 352 HWMON_I_INPUT | HWMON_I_ENABLE | HWMON_I_LABEL, 353 HWMON_I_INPUT | HWMON_I_ENABLE | HWMON_I_LABEL, 354 HWMON_I_INPUT | HWMON_I_LABEL), 355 HWMON_CHANNEL_INFO(curr, 356 HWMON_C_INPUT | HWMON_C_LABEL, 357 HWMON_C_INPUT | HWMON_C_LABEL, 358 HWMON_C_INPUT | HWMON_C_LABEL, 359 HWMON_C_INPUT | HWMON_C_LABEL), 360 NULL 361 }; 362 363 static const struct hwmon_ops tps23861_hwmon_ops = { 364 .is_visible = tps23861_is_visible, 365 .write = tps23861_write, 366 .read = tps23861_read, 367 .read_string = tps23861_read_string, 368 }; 369 370 static const struct hwmon_chip_info tps23861_chip_info = { 371 .ops = &tps23861_hwmon_ops, 372 .info = tps23861_info, 373 }; 374 375 static char *port_operating_mode_string(uint8_t mode_reg, unsigned int port) 376 { 377 unsigned int mode = ~0; 378 379 if (port < TPS23861_NUM_PORTS) 380 mode = (mode_reg >> (2 * port)) & OPERATING_MODE_PORT_1_MASK; 381 382 switch (mode) { 383 case OPERATING_MODE_OFF: 384 return "Off"; 385 case OPERATING_MODE_MANUAL: 386 return "Manual"; 387 case OPERATING_MODE_SEMI: 388 return "Semi-Auto"; 389 case OPERATING_MODE_AUTO: 390 return "Auto"; 391 default: 392 return "Invalid"; 393 } 394 } 395 396 static char *port_detect_status_string(uint8_t status_reg) 397 { 398 switch (FIELD_GET(PORT_STATUS_DETECT_MASK, status_reg)) { 399 case PORT_DETECT_UNKNOWN: 400 return "Unknown device"; 401 case PORT_DETECT_SHORT: 402 return "Short circuit"; 403 case PORT_DETECT_RESISTANCE_LOW: 404 return "Too low resistance"; 405 case PORT_DETECT_RESISTANCE_OK: 406 return "Valid resistance"; 407 case PORT_DETECT_RESISTANCE_HIGH: 408 return "Too high resistance"; 409 case PORT_DETECT_OPEN_CIRCUIT: 410 return "Open circuit"; 411 case PORT_DETECT_MOSFET_FAULT: 412 return "MOSFET fault"; 413 case PORT_DETECT_LEGACY: 414 return "Legacy device"; 415 case PORT_DETECT_CAPACITANCE_INVALID_BEYOND: 416 return "Invalid capacitance, beyond clamp voltage"; 417 case PORT_DETECT_CAPACITANCE_INVALID_DELTA: 418 return "Invalid capacitance, insufficient voltage delta"; 419 case PORT_DETECT_CAPACITANCE_OUT_OF_RANGE: 420 return "Valid capacitance, outside of legacy range"; 421 case PORT_DETECT_RESERVED: 422 case PORT_DETECT_RESERVED_2: 423 default: 424 return "Invalid"; 425 } 426 } 427 428 static char *port_class_status_string(uint8_t status_reg) 429 { 430 switch (FIELD_GET(PORT_STATUS_CLASS_MASK, status_reg)) { 431 case PORT_CLASS_UNKNOWN: 432 return "Unknown"; 433 case PORT_CLASS_RESERVED: 434 case PORT_CLASS_0: 435 return "0"; 436 case PORT_CLASS_1: 437 return "1"; 438 case PORT_CLASS_2: 439 return "2"; 440 case PORT_CLASS_3: 441 return "3"; 442 case PORT_CLASS_4: 443 return "4"; 444 case PORT_CLASS_OVERCURRENT: 445 return "Overcurrent"; 446 case PORT_CLASS_MISMATCH: 447 return "Mismatch"; 448 default: 449 return "Invalid"; 450 } 451 } 452 453 static char *port_poe_plus_status_string(uint8_t poe_plus, unsigned int port) 454 { 455 return (BIT(port + 4) & poe_plus) ? "Yes" : "No"; 456 } 457 458 static int tps23861_port_resistance(struct tps23861_data *data, int port) 459 { 460 unsigned int raw_val; 461 __le16 regval; 462 463 regmap_bulk_read(data->regmap, 464 PORT_1_RESISTANCE_LSB + PORT_N_RESISTANCE_LSB_OFFSET * port, 465 ®val, 466 2); 467 468 raw_val = le16_to_cpu(regval); 469 switch (FIELD_GET(PORT_RESISTANCE_RSN_MASK, raw_val)) { 470 case PORT_RESISTANCE_RSN_OTHER: 471 return (FIELD_GET(PORT_RESISTANCE_MASK, raw_val) * RESISTANCE_LSB) / 10000; 472 case PORT_RESISTANCE_RSN_LOW: 473 return (FIELD_GET(PORT_RESISTANCE_MASK, raw_val) * RESISTANCE_LSB_LOW) / 10000; 474 case PORT_RESISTANCE_RSN_SHORT: 475 case PORT_RESISTANCE_RSN_OPEN: 476 default: 477 return 0; 478 } 479 } 480 481 static int tps23861_port_status_show(struct seq_file *s, void *data) 482 { 483 struct tps23861_data *priv = s->private; 484 unsigned int i, mode, poe_plus, status; 485 486 regmap_read(priv->regmap, OPERATING_MODE, &mode); 487 regmap_read(priv->regmap, POE_PLUS, &poe_plus); 488 489 for (i = 0; i < TPS23861_NUM_PORTS; i++) { 490 regmap_read(priv->regmap, PORT_1_STATUS + i, &status); 491 492 seq_printf(s, "Port: \t\t%d\n", i + 1); 493 seq_printf(s, "Operating mode: %s\n", port_operating_mode_string(mode, i)); 494 seq_printf(s, "Detected: \t%s\n", port_detect_status_string(status)); 495 seq_printf(s, "Class: \t\t%s\n", port_class_status_string(status)); 496 seq_printf(s, "PoE Plus: \t%s\n", port_poe_plus_status_string(poe_plus, i)); 497 seq_printf(s, "Resistance: \t%d\n", tps23861_port_resistance(priv, i)); 498 seq_putc(s, '\n'); 499 } 500 501 return 0; 502 } 503 504 DEFINE_SHOW_ATTRIBUTE(tps23861_port_status); 505 506 static void tps23861_init_debugfs(struct tps23861_data *data, 507 struct device *hwmon_dev) 508 { 509 const char *debugfs_name; 510 511 debugfs_name = devm_kasprintf(&data->client->dev, GFP_KERNEL, "%s-%s", 512 data->client->name, dev_name(hwmon_dev)); 513 if (!debugfs_name) 514 return; 515 516 data->debugfs_dir = debugfs_create_dir(debugfs_name, NULL); 517 518 debugfs_create_file("port_status", 519 0400, 520 data->debugfs_dir, 521 data, 522 &tps23861_port_status_fops); 523 } 524 525 static int tps23861_probe(struct i2c_client *client) 526 { 527 struct device *dev = &client->dev; 528 struct tps23861_data *data; 529 struct device *hwmon_dev; 530 u32 shunt_resistor; 531 532 data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL); 533 if (!data) 534 return -ENOMEM; 535 536 data->client = client; 537 i2c_set_clientdata(client, data); 538 539 data->regmap = devm_regmap_init_i2c(client, &tps23861_regmap_config); 540 if (IS_ERR(data->regmap)) { 541 dev_err(dev, "failed to allocate register map\n"); 542 return PTR_ERR(data->regmap); 543 } 544 545 if (!of_property_read_u32(dev->of_node, "shunt-resistor-micro-ohms", &shunt_resistor)) 546 data->shunt_resistor = shunt_resistor; 547 else 548 data->shunt_resistor = SHUNT_RESISTOR_DEFAULT; 549 550 if (data->shunt_resistor == SHUNT_RESISTOR_DEFAULT) 551 regmap_clear_bits(data->regmap, 552 TPS23861_GENERAL_MASK_1, 553 TPS23861_CURRENT_SHUNT_MASK); 554 else 555 regmap_set_bits(data->regmap, 556 TPS23861_GENERAL_MASK_1, 557 TPS23861_CURRENT_SHUNT_MASK); 558 559 hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name, 560 data, &tps23861_chip_info, 561 NULL); 562 if (IS_ERR(hwmon_dev)) 563 return PTR_ERR(hwmon_dev); 564 565 tps23861_init_debugfs(data, hwmon_dev); 566 567 return 0; 568 } 569 570 static void tps23861_remove(struct i2c_client *client) 571 { 572 struct tps23861_data *data = i2c_get_clientdata(client); 573 574 debugfs_remove_recursive(data->debugfs_dir); 575 } 576 577 static const struct of_device_id __maybe_unused tps23861_of_match[] = { 578 { .compatible = "ti,tps23861", }, 579 { }, 580 }; 581 MODULE_DEVICE_TABLE(of, tps23861_of_match); 582 583 static struct i2c_driver tps23861_driver = { 584 .probe_new = tps23861_probe, 585 .remove = tps23861_remove, 586 .driver = { 587 .name = "tps23861", 588 .of_match_table = of_match_ptr(tps23861_of_match), 589 }, 590 }; 591 module_i2c_driver(tps23861_driver); 592 593 MODULE_LICENSE("GPL"); 594 MODULE_AUTHOR("Robert Marko <robert.marko@sartura.hr>"); 595 MODULE_DESCRIPTION("TI TPS23861 PoE PSE"); 596