1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * OF helpers for regulator framework 4 * 5 * Copyright (C) 2011 Texas Instruments, Inc. 6 * Rajendra Nayak <rnayak@ti.com> 7 */ 8 9 #include <linux/module.h> 10 #include <linux/slab.h> 11 #include <linux/of.h> 12 #include <linux/regulator/machine.h> 13 #include <linux/regulator/driver.h> 14 #include <linux/regulator/of_regulator.h> 15 16 #include "internal.h" 17 18 static const char *const regulator_states[PM_SUSPEND_MAX + 1] = { 19 [PM_SUSPEND_STANDBY] = "regulator-state-standby", 20 [PM_SUSPEND_MEM] = "regulator-state-mem", 21 [PM_SUSPEND_MAX] = "regulator-state-disk", 22 }; 23 24 static int of_get_regulation_constraints(struct device *dev, 25 struct device_node *np, 26 struct regulator_init_data **init_data, 27 const struct regulator_desc *desc) 28 { 29 struct regulation_constraints *constraints = &(*init_data)->constraints; 30 struct regulator_state *suspend_state; 31 struct device_node *suspend_np; 32 unsigned int mode; 33 int ret, i, len; 34 int n_phandles; 35 u32 pval; 36 37 n_phandles = of_count_phandle_with_args(np, "regulator-coupled-with", 38 NULL); 39 n_phandles = max(n_phandles, 0); 40 41 constraints->name = of_get_property(np, "regulator-name", NULL); 42 43 if (!of_property_read_u32(np, "regulator-min-microvolt", &pval)) 44 constraints->min_uV = pval; 45 46 if (!of_property_read_u32(np, "regulator-max-microvolt", &pval)) 47 constraints->max_uV = pval; 48 49 /* Voltage change possible? */ 50 if (constraints->min_uV != constraints->max_uV) 51 constraints->valid_ops_mask |= REGULATOR_CHANGE_VOLTAGE; 52 53 /* Do we have a voltage range, if so try to apply it? */ 54 if (constraints->min_uV && constraints->max_uV) 55 constraints->apply_uV = true; 56 57 if (!of_property_read_u32(np, "regulator-microvolt-offset", &pval)) 58 constraints->uV_offset = pval; 59 if (!of_property_read_u32(np, "regulator-min-microamp", &pval)) 60 constraints->min_uA = pval; 61 if (!of_property_read_u32(np, "regulator-max-microamp", &pval)) 62 constraints->max_uA = pval; 63 64 if (!of_property_read_u32(np, "regulator-input-current-limit-microamp", 65 &pval)) 66 constraints->ilim_uA = pval; 67 68 /* Current change possible? */ 69 if (constraints->min_uA != constraints->max_uA) 70 constraints->valid_ops_mask |= REGULATOR_CHANGE_CURRENT; 71 72 constraints->boot_on = of_property_read_bool(np, "regulator-boot-on"); 73 constraints->always_on = of_property_read_bool(np, "regulator-always-on"); 74 if (!constraints->always_on) /* status change should be possible. */ 75 constraints->valid_ops_mask |= REGULATOR_CHANGE_STATUS; 76 77 constraints->pull_down = of_property_read_bool(np, "regulator-pull-down"); 78 79 if (of_property_read_bool(np, "regulator-allow-bypass")) 80 constraints->valid_ops_mask |= REGULATOR_CHANGE_BYPASS; 81 82 if (of_property_read_bool(np, "regulator-allow-set-load")) 83 constraints->valid_ops_mask |= REGULATOR_CHANGE_DRMS; 84 85 ret = of_property_read_u32(np, "regulator-ramp-delay", &pval); 86 if (!ret) { 87 if (pval) 88 constraints->ramp_delay = pval; 89 else 90 constraints->ramp_disable = true; 91 } 92 93 ret = of_property_read_u32(np, "regulator-settling-time-us", &pval); 94 if (!ret) 95 constraints->settling_time = pval; 96 97 ret = of_property_read_u32(np, "regulator-settling-time-up-us", &pval); 98 if (!ret) 99 constraints->settling_time_up = pval; 100 if (constraints->settling_time_up && constraints->settling_time) { 101 pr_warn("%pOFn: ambiguous configuration for settling time, ignoring 'regulator-settling-time-up-us'\n", 102 np); 103 constraints->settling_time_up = 0; 104 } 105 106 ret = of_property_read_u32(np, "regulator-settling-time-down-us", 107 &pval); 108 if (!ret) 109 constraints->settling_time_down = pval; 110 if (constraints->settling_time_down && constraints->settling_time) { 111 pr_warn("%pOFn: ambiguous configuration for settling time, ignoring 'regulator-settling-time-down-us'\n", 112 np); 113 constraints->settling_time_down = 0; 114 } 115 116 ret = of_property_read_u32(np, "regulator-enable-ramp-delay", &pval); 117 if (!ret) 118 constraints->enable_time = pval; 119 120 constraints->soft_start = of_property_read_bool(np, 121 "regulator-soft-start"); 122 ret = of_property_read_u32(np, "regulator-active-discharge", &pval); 123 if (!ret) { 124 constraints->active_discharge = 125 (pval) ? REGULATOR_ACTIVE_DISCHARGE_ENABLE : 126 REGULATOR_ACTIVE_DISCHARGE_DISABLE; 127 } 128 129 if (!of_property_read_u32(np, "regulator-initial-mode", &pval)) { 130 if (desc && desc->of_map_mode) { 131 mode = desc->of_map_mode(pval); 132 if (mode == REGULATOR_MODE_INVALID) 133 pr_err("%pOFn: invalid mode %u\n", np, pval); 134 else 135 constraints->initial_mode = mode; 136 } else { 137 pr_warn("%pOFn: mapping for mode %d not defined\n", 138 np, pval); 139 } 140 } 141 142 len = of_property_count_elems_of_size(np, "regulator-allowed-modes", 143 sizeof(u32)); 144 if (len > 0) { 145 if (desc && desc->of_map_mode) { 146 for (i = 0; i < len; i++) { 147 ret = of_property_read_u32_index(np, 148 "regulator-allowed-modes", i, &pval); 149 if (ret) { 150 pr_err("%pOFn: couldn't read allowed modes index %d, ret=%d\n", 151 np, i, ret); 152 break; 153 } 154 mode = desc->of_map_mode(pval); 155 if (mode == REGULATOR_MODE_INVALID) 156 pr_err("%pOFn: invalid regulator-allowed-modes element %u\n", 157 np, pval); 158 else 159 constraints->valid_modes_mask |= mode; 160 } 161 if (constraints->valid_modes_mask) 162 constraints->valid_ops_mask 163 |= REGULATOR_CHANGE_MODE; 164 } else { 165 pr_warn("%pOFn: mode mapping not defined\n", np); 166 } 167 } 168 169 if (!of_property_read_u32(np, "regulator-system-load", &pval)) 170 constraints->system_load = pval; 171 172 if (n_phandles) { 173 constraints->max_spread = devm_kzalloc(dev, 174 sizeof(*constraints->max_spread) * n_phandles, 175 GFP_KERNEL); 176 177 if (!constraints->max_spread) 178 return -ENOMEM; 179 180 of_property_read_u32_array(np, "regulator-coupled-max-spread", 181 constraints->max_spread, n_phandles); 182 } 183 184 if (!of_property_read_u32(np, "regulator-max-step-microvolt", 185 &pval)) 186 constraints->max_uV_step = pval; 187 188 constraints->over_current_protection = of_property_read_bool(np, 189 "regulator-over-current-protection"); 190 191 for (i = 0; i < ARRAY_SIZE(regulator_states); i++) { 192 switch (i) { 193 case PM_SUSPEND_MEM: 194 suspend_state = &constraints->state_mem; 195 break; 196 case PM_SUSPEND_MAX: 197 suspend_state = &constraints->state_disk; 198 break; 199 case PM_SUSPEND_STANDBY: 200 suspend_state = &constraints->state_standby; 201 break; 202 case PM_SUSPEND_ON: 203 case PM_SUSPEND_TO_IDLE: 204 default: 205 continue; 206 } 207 208 suspend_np = of_get_child_by_name(np, regulator_states[i]); 209 if (!suspend_np || !suspend_state) 210 continue; 211 212 if (!of_property_read_u32(suspend_np, "regulator-mode", 213 &pval)) { 214 if (desc && desc->of_map_mode) { 215 mode = desc->of_map_mode(pval); 216 if (mode == REGULATOR_MODE_INVALID) 217 pr_err("%pOFn: invalid mode %u\n", 218 np, pval); 219 else 220 suspend_state->mode = mode; 221 } else { 222 pr_warn("%pOFn: mapping for mode %d not defined\n", 223 np, pval); 224 } 225 } 226 227 if (of_property_read_bool(suspend_np, 228 "regulator-on-in-suspend")) 229 suspend_state->enabled = ENABLE_IN_SUSPEND; 230 else if (of_property_read_bool(suspend_np, 231 "regulator-off-in-suspend")) 232 suspend_state->enabled = DISABLE_IN_SUSPEND; 233 234 if (!of_property_read_u32(np, "regulator-suspend-min-microvolt", 235 &pval)) 236 suspend_state->min_uV = pval; 237 238 if (!of_property_read_u32(np, "regulator-suspend-max-microvolt", 239 &pval)) 240 suspend_state->max_uV = pval; 241 242 if (!of_property_read_u32(suspend_np, 243 "regulator-suspend-microvolt", &pval)) 244 suspend_state->uV = pval; 245 else /* otherwise use min_uV as default suspend voltage */ 246 suspend_state->uV = suspend_state->min_uV; 247 248 if (of_property_read_bool(suspend_np, 249 "regulator-changeable-in-suspend")) 250 suspend_state->changeable = true; 251 252 if (i == PM_SUSPEND_MEM) 253 constraints->initial_state = PM_SUSPEND_MEM; 254 255 of_node_put(suspend_np); 256 suspend_state = NULL; 257 suspend_np = NULL; 258 } 259 260 return 0; 261 } 262 263 /** 264 * of_get_regulator_init_data - extract regulator_init_data structure info 265 * @dev: device requesting for regulator_init_data 266 * @node: regulator device node 267 * @desc: regulator description 268 * 269 * Populates regulator_init_data structure by extracting data from device 270 * tree node, returns a pointer to the populated structure or NULL if memory 271 * alloc fails. 272 */ 273 struct regulator_init_data *of_get_regulator_init_data(struct device *dev, 274 struct device_node *node, 275 const struct regulator_desc *desc) 276 { 277 struct regulator_init_data *init_data; 278 279 if (!node) 280 return NULL; 281 282 init_data = devm_kzalloc(dev, sizeof(*init_data), GFP_KERNEL); 283 if (!init_data) 284 return NULL; /* Out of memory? */ 285 286 if (of_get_regulation_constraints(dev, node, &init_data, desc)) 287 return NULL; 288 289 return init_data; 290 } 291 EXPORT_SYMBOL_GPL(of_get_regulator_init_data); 292 293 struct devm_of_regulator_matches { 294 struct of_regulator_match *matches; 295 unsigned int num_matches; 296 }; 297 298 static void devm_of_regulator_put_matches(struct device *dev, void *res) 299 { 300 struct devm_of_regulator_matches *devm_matches = res; 301 int i; 302 303 for (i = 0; i < devm_matches->num_matches; i++) 304 of_node_put(devm_matches->matches[i].of_node); 305 } 306 307 /** 308 * of_regulator_match - extract multiple regulator init data from device tree. 309 * @dev: device requesting the data 310 * @node: parent device node of the regulators 311 * @matches: match table for the regulators 312 * @num_matches: number of entries in match table 313 * 314 * This function uses a match table specified by the regulator driver to 315 * parse regulator init data from the device tree. @node is expected to 316 * contain a set of child nodes, each providing the init data for one 317 * regulator. The data parsed from a child node will be matched to a regulator 318 * based on either the deprecated property regulator-compatible if present, 319 * or otherwise the child node's name. Note that the match table is modified 320 * in place and an additional of_node reference is taken for each matched 321 * regulator. 322 * 323 * Returns the number of matches found or a negative error code on failure. 324 */ 325 int of_regulator_match(struct device *dev, struct device_node *node, 326 struct of_regulator_match *matches, 327 unsigned int num_matches) 328 { 329 unsigned int count = 0; 330 unsigned int i; 331 const char *name; 332 struct device_node *child; 333 struct devm_of_regulator_matches *devm_matches; 334 335 if (!dev || !node) 336 return -EINVAL; 337 338 devm_matches = devres_alloc(devm_of_regulator_put_matches, 339 sizeof(struct devm_of_regulator_matches), 340 GFP_KERNEL); 341 if (!devm_matches) 342 return -ENOMEM; 343 344 devm_matches->matches = matches; 345 devm_matches->num_matches = num_matches; 346 347 devres_add(dev, devm_matches); 348 349 for (i = 0; i < num_matches; i++) { 350 struct of_regulator_match *match = &matches[i]; 351 match->init_data = NULL; 352 match->of_node = NULL; 353 } 354 355 for_each_child_of_node(node, child) { 356 name = of_get_property(child, 357 "regulator-compatible", NULL); 358 if (!name) 359 name = child->name; 360 for (i = 0; i < num_matches; i++) { 361 struct of_regulator_match *match = &matches[i]; 362 if (match->of_node) 363 continue; 364 365 if (strcmp(match->name, name)) 366 continue; 367 368 match->init_data = 369 of_get_regulator_init_data(dev, child, 370 match->desc); 371 if (!match->init_data) { 372 dev_err(dev, 373 "failed to parse DT for regulator %pOFn\n", 374 child); 375 of_node_put(child); 376 return -EINVAL; 377 } 378 match->of_node = of_node_get(child); 379 count++; 380 break; 381 } 382 } 383 384 return count; 385 } 386 EXPORT_SYMBOL_GPL(of_regulator_match); 387 388 static struct 389 device_node *regulator_of_get_init_node(struct device *dev, 390 const struct regulator_desc *desc) 391 { 392 struct device_node *search, *child; 393 const char *name; 394 395 if (!dev->of_node || !desc->of_match) 396 return NULL; 397 398 if (desc->regulators_node) { 399 search = of_get_child_by_name(dev->of_node, 400 desc->regulators_node); 401 } else { 402 search = of_node_get(dev->of_node); 403 404 if (!strcmp(desc->of_match, search->name)) 405 return search; 406 } 407 408 if (!search) { 409 dev_dbg(dev, "Failed to find regulator container node '%s'\n", 410 desc->regulators_node); 411 return NULL; 412 } 413 414 for_each_available_child_of_node(search, child) { 415 name = of_get_property(child, "regulator-compatible", NULL); 416 if (!name) 417 name = child->name; 418 419 if (!strcmp(desc->of_match, name)) { 420 of_node_put(search); 421 return of_node_get(child); 422 } 423 } 424 425 of_node_put(search); 426 427 return NULL; 428 } 429 430 struct regulator_init_data *regulator_of_get_init_data(struct device *dev, 431 const struct regulator_desc *desc, 432 struct regulator_config *config, 433 struct device_node **node) 434 { 435 struct device_node *child; 436 struct regulator_init_data *init_data = NULL; 437 438 child = regulator_of_get_init_node(dev, desc); 439 if (!child) 440 return NULL; 441 442 init_data = of_get_regulator_init_data(dev, child, desc); 443 if (!init_data) { 444 dev_err(dev, "failed to parse DT for regulator %pOFn\n", child); 445 goto error; 446 } 447 448 if (desc->of_parse_cb && desc->of_parse_cb(child, desc, config)) { 449 dev_err(dev, 450 "driver callback failed to parse DT for regulator %pOFn\n", 451 child); 452 goto error; 453 } 454 455 *node = child; 456 457 return init_data; 458 459 error: 460 of_node_put(child); 461 462 return NULL; 463 } 464 465 struct regulator_dev *of_find_regulator_by_node(struct device_node *np) 466 { 467 struct device *dev; 468 469 dev = class_find_device_by_of_node(®ulator_class, np); 470 471 return dev ? dev_to_rdev(dev) : NULL; 472 } 473 474 /* 475 * Returns number of regulators coupled with rdev. 476 */ 477 int of_get_n_coupled(struct regulator_dev *rdev) 478 { 479 struct device_node *node = rdev->dev.of_node; 480 int n_phandles; 481 482 n_phandles = of_count_phandle_with_args(node, 483 "regulator-coupled-with", 484 NULL); 485 486 return (n_phandles > 0) ? n_phandles : 0; 487 } 488 489 /* Looks for "to_find" device_node in src's "regulator-coupled-with" property */ 490 static bool of_coupling_find_node(struct device_node *src, 491 struct device_node *to_find, 492 int *index) 493 { 494 int n_phandles, i; 495 bool found = false; 496 497 n_phandles = of_count_phandle_with_args(src, 498 "regulator-coupled-with", 499 NULL); 500 501 for (i = 0; i < n_phandles; i++) { 502 struct device_node *tmp = of_parse_phandle(src, 503 "regulator-coupled-with", i); 504 505 if (!tmp) 506 break; 507 508 /* found */ 509 if (tmp == to_find) 510 found = true; 511 512 of_node_put(tmp); 513 514 if (found) { 515 *index = i; 516 break; 517 } 518 } 519 520 return found; 521 } 522 523 /** 524 * of_check_coupling_data - Parse rdev's coupling properties and check data 525 * consistency 526 * @rdev - pointer to regulator_dev whose data is checked 527 * 528 * Function checks if all the following conditions are met: 529 * - rdev's max_spread is greater than 0 530 * - all coupled regulators have the same max_spread 531 * - all coupled regulators have the same number of regulator_dev phandles 532 * - all regulators are linked to each other 533 * 534 * Returns true if all conditions are met. 535 */ 536 bool of_check_coupling_data(struct regulator_dev *rdev) 537 { 538 struct device_node *node = rdev->dev.of_node; 539 int n_phandles = of_get_n_coupled(rdev); 540 struct device_node *c_node; 541 int index; 542 int i; 543 bool ret = true; 544 545 /* iterate over rdev's phandles */ 546 for (i = 0; i < n_phandles; i++) { 547 int max_spread = rdev->constraints->max_spread[i]; 548 int c_max_spread, c_n_phandles; 549 550 if (max_spread <= 0) { 551 dev_err(&rdev->dev, "max_spread value invalid\n"); 552 return false; 553 } 554 555 c_node = of_parse_phandle(node, 556 "regulator-coupled-with", i); 557 558 if (!c_node) 559 ret = false; 560 561 c_n_phandles = of_count_phandle_with_args(c_node, 562 "regulator-coupled-with", 563 NULL); 564 565 if (c_n_phandles != n_phandles) { 566 dev_err(&rdev->dev, "number of coupled reg phandles mismatch\n"); 567 ret = false; 568 goto clean; 569 } 570 571 if (!of_coupling_find_node(c_node, node, &index)) { 572 dev_err(&rdev->dev, "missing 2-way linking for coupled regulators\n"); 573 ret = false; 574 goto clean; 575 } 576 577 if (of_property_read_u32_index(c_node, "regulator-coupled-max-spread", 578 index, &c_max_spread)) { 579 ret = false; 580 goto clean; 581 } 582 583 if (c_max_spread != max_spread) { 584 dev_err(&rdev->dev, 585 "coupled regulators max_spread mismatch\n"); 586 ret = false; 587 goto clean; 588 } 589 590 clean: 591 of_node_put(c_node); 592 if (!ret) 593 break; 594 } 595 596 return ret; 597 } 598 599 /** 600 * of_parse_coupled regulator - Get regulator_dev pointer from rdev's property 601 * @rdev: Pointer to regulator_dev, whose DTS is used as a source to parse 602 * "regulator-coupled-with" property 603 * @index: Index in phandles array 604 * 605 * Returns the regulator_dev pointer parsed from DTS. If it has not been yet 606 * registered, returns NULL 607 */ 608 struct regulator_dev *of_parse_coupled_regulator(struct regulator_dev *rdev, 609 int index) 610 { 611 struct device_node *node = rdev->dev.of_node; 612 struct device_node *c_node; 613 struct regulator_dev *c_rdev; 614 615 c_node = of_parse_phandle(node, "regulator-coupled-with", index); 616 if (!c_node) 617 return NULL; 618 619 c_rdev = of_find_regulator_by_node(c_node); 620 621 of_node_put(c_node); 622 623 return c_rdev; 624 } 625