drivers/regulator/of_regulator.c

   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 void fill_limit(int *limit, int val)
  25 {
  26         if (val)
  27                 if (val == 1)
  28                         *limit = REGULATOR_NOTIF_LIMIT_ENABLE;
  29                 else
  30                         *limit = val;
  31         else
  32                 *limit = REGULATOR_NOTIF_LIMIT_DISABLE;
  33 }
  34
  35 static void of_get_regulator_prot_limits(struct device_node *np,
  36                                 struct regulation_constraints *constraints)
  37 {
  38         u32 pval;
  39         int i;
  40         static const char *const props[] = {
  41                 "regulator-oc-%s-microamp",
  42                 "regulator-ov-%s-microvolt",
  43                 "regulator-temp-%s-kelvin",
  44                 "regulator-uv-%s-microvolt",
  45         };
  46         struct notification_limit *limits[] = {
  47                 &constraints->over_curr_limits,
  48                 &constraints->over_voltage_limits,
  49                 &constraints->temp_limits,
  50                 &constraints->under_voltage_limits,
  51         };
  52         bool set[4] = {0};
  53
  54         /* Protection limits: */
  55         for (i = 0; i < ARRAY_SIZE(props); i++) {
  56                 char prop[255];
  57                 bool found;
  58                 int j;
  59                 static const char *const lvl[] = {
  60                         "protection", "error", "warn"
  61                 };
  62                 int *l[] = {
  63                         &limits[i]->prot, &limits[i]->err, &limits[i]->warn,
  64                 };
  65
  66                 for (j = 0; j < ARRAY_SIZE(lvl); j++) {
  67                         snprintf(prop, 255, props[i], lvl[j]);
  68                         found = !of_property_read_u32(np, prop, &pval);
  69                         if (found)
  70                                 fill_limit(l[j], pval);
  71                         set[i] |= found;
  72                 }
  73         }
  74         constraints->over_current_detection = set[0];
  75         constraints->over_voltage_detection = set[1];
  76         constraints->over_temp_detection = set[2];
  77         constraints->under_voltage_detection = set[3];
  78 }
  79
  80 static int of_get_regulation_constraints(struct device *dev,
  81                                         struct device_node *np,
  82                                         struct regulator_init_data **init_data,
  83                                         const struct regulator_desc *desc)
  84 {
  85         struct regulation_constraints *constraints = &(*init_data)->constraints;
  86         struct regulator_state *suspend_state;
  87         struct device_node *suspend_np;
  88         unsigned int mode;
  89         int ret, i, len;
  90         int n_phandles;
  91         u32 pval;
  92
  93         n_phandles = of_count_phandle_with_args(np, "regulator-coupled-with",
  94                                                 NULL);
  95         n_phandles = max(n_phandles, 0);
  96
  97         constraints->name = of_get_property(np, "regulator-name", NULL);
  98
  99         if (!of_property_read_u32(np, "regulator-min-microvolt", &pval))
 100                 constraints->min_uV = pval;
 101
 102         if (!of_property_read_u32(np, "regulator-max-microvolt", &pval))
 103                 constraints->max_uV = pval;
 104
 105         /* Voltage change possible? */
 106         if (constraints->min_uV != constraints->max_uV)
 107                 constraints->valid_ops_mask |= REGULATOR_CHANGE_VOLTAGE;
 108
 109         /* Do we have a voltage range, if so try to apply it? */
 110         if (constraints->min_uV && constraints->max_uV)
 111                 constraints->apply_uV = true;
 112
 113         if (!of_property_read_u32(np, "regulator-microvolt-offset", &pval))
 114                 constraints->uV_offset = pval;
 115         if (!of_property_read_u32(np, "regulator-min-microamp", &pval))
 116                 constraints->min_uA = pval;
 117         if (!of_property_read_u32(np, "regulator-max-microamp", &pval))
 118                 constraints->max_uA = pval;
 119
 120         if (!of_property_read_u32(np, "regulator-input-current-limit-microamp",
 121                                   &pval))
 122                 constraints->ilim_uA = pval;
 123
 124         /* Current change possible? */
 125         if (constraints->min_uA != constraints->max_uA)
 126                 constraints->valid_ops_mask |= REGULATOR_CHANGE_CURRENT;
 127
 128         if (!of_property_read_u32(np, "regulator-power-budget-milliwatt", &pval))
 129                 constraints->pw_budget_mW = pval;
 130
 131         constraints->boot_on = of_property_read_bool(np, "regulator-boot-on");
 132         constraints->always_on = of_property_read_bool(np, "regulator-always-on");
 133         if (!constraints->always_on) /* status change should be possible. */
 134                 constraints->valid_ops_mask |= REGULATOR_CHANGE_STATUS;
 135
 136         constraints->pull_down = of_property_read_bool(np, "regulator-pull-down");
 137         constraints->system_critical = of_property_read_bool(np,
 138                                                 "system-critical-regulator");
 139
 140         if (of_property_read_bool(np, "regulator-allow-bypass"))
 141                 constraints->valid_ops_mask |= REGULATOR_CHANGE_BYPASS;
 142
 143         if (of_property_read_bool(np, "regulator-allow-set-load"))
 144                 constraints->valid_ops_mask |= REGULATOR_CHANGE_DRMS;
 145
 146         ret = of_property_read_u32(np, "regulator-ramp-delay", &pval);
 147         if (!ret) {
 148                 if (pval)
 149                         constraints->ramp_delay = pval;
 150                 else
 151                         constraints->ramp_disable = true;
 152         }
 153
 154         ret = of_property_read_u32(np, "regulator-settling-time-us", &pval);
 155         if (!ret)
 156                 constraints->settling_time = pval;
 157
 158         ret = of_property_read_u32(np, "regulator-settling-time-up-us", &pval);
 159         if (!ret)
 160                 constraints->settling_time_up = pval;
 161         if (constraints->settling_time_up && constraints->settling_time) {
 162                 pr_warn("%pOFn: ambiguous configuration for settling time, ignoring 'regulator-settling-time-up-us'\n",
 163                         np);
 164                 constraints->settling_time_up = 0;
 165         }
 166
 167         ret = of_property_read_u32(np, "regulator-settling-time-down-us",
 168                                    &pval);
 169         if (!ret)
 170                 constraints->settling_time_down = pval;
 171         if (constraints->settling_time_down && constraints->settling_time) {
 172                 pr_warn("%pOFn: ambiguous configuration for settling time, ignoring 'regulator-settling-time-down-us'\n",
 173                         np);
 174                 constraints->settling_time_down = 0;
 175         }
 176
 177         ret = of_property_read_u32(np, "regulator-enable-ramp-delay", &pval);
 178         if (!ret)
 179                 constraints->enable_time = pval;
 180
 181         ret = of_property_read_u32(np, "regulator-uv-less-critical-window-ms", &pval);
 182         if (!ret)
 183                 constraints->uv_less_critical_window_ms = pval;
 184         else
 185                 constraints->uv_less_critical_window_ms =
 186                                 REGULATOR_DEF_UV_LESS_CRITICAL_WINDOW_MS;
 187
 188         constraints->soft_start = of_property_read_bool(np,
 189                                         "regulator-soft-start");
 190         ret = of_property_read_u32(np, "regulator-active-discharge", &pval);
 191         if (!ret) {
 192                 constraints->active_discharge =
 193                                 (pval) ? REGULATOR_ACTIVE_DISCHARGE_ENABLE :
 194                                         REGULATOR_ACTIVE_DISCHARGE_DISABLE;
 195         }
 196
 197         if (!of_property_read_u32(np, "regulator-initial-mode", &pval)) {
 198                 if (desc && desc->of_map_mode) {
 199                         mode = desc->of_map_mode(pval);
 200                         if (mode == REGULATOR_MODE_INVALID)
 201                                 pr_err("%pOFn: invalid mode %u\n", np, pval);
 202                         else
 203                                 constraints->initial_mode = mode;
 204                 } else {
 205                         pr_warn("%pOFn: mapping for mode %d not defined\n",
 206                                 np, pval);
 207                 }
 208         }
 209
 210         len = of_property_count_elems_of_size(np, "regulator-allowed-modes",
 211                                                 sizeof(u32));
 212         if (len > 0) {
 213                 if (desc && desc->of_map_mode) {
 214                         for (i = 0; i < len; i++) {
 215                                 ret = of_property_read_u32_index(np,
 216                                         "regulator-allowed-modes", i, &pval);
 217                                 if (ret) {
 218                                         pr_err("%pOFn: couldn't read allowed modes index %d, ret=%d\n",
 219                                                 np, i, ret);
 220                                         break;
 221                                 }
 222                                 mode = desc->of_map_mode(pval);
 223                                 if (mode == REGULATOR_MODE_INVALID)
 224                                         pr_err("%pOFn: invalid regulator-allowed-modes element %u\n",
 225                                                 np, pval);
 226                                 else
 227                                         constraints->valid_modes_mask |= mode;
 228                         }
 229                         if (constraints->valid_modes_mask)
 230                                 constraints->valid_ops_mask
 231                                         |= REGULATOR_CHANGE_MODE;
 232                 } else {
 233                         pr_warn("%pOFn: mode mapping not defined\n", np);
 234                 }
 235         }
 236
 237         if (!of_property_read_u32(np, "regulator-system-load", &pval))
 238                 constraints->system_load = pval;
 239
 240         if (n_phandles) {
 241                 constraints->max_spread = devm_kzalloc(dev,
 242                                 sizeof(*constraints->max_spread) * n_phandles,
 243                                 GFP_KERNEL);
 244
 245                 if (!constraints->max_spread)
 246                         return -ENOMEM;
 247
 248                 of_property_read_u32_array(np, "regulator-coupled-max-spread",
 249                                            constraints->max_spread, n_phandles);
 250         }
 251
 252         if (!of_property_read_u32(np, "regulator-max-step-microvolt",
 253                                   &pval))
 254                 constraints->max_uV_step = pval;
 255
 256         constraints->over_current_protection = of_property_read_bool(np,
 257                                         "regulator-over-current-protection");
 258
 259         of_get_regulator_prot_limits(np, constraints);
 260
 261         for (i = 0; i < ARRAY_SIZE(regulator_states); i++) {
 262                 switch (i) {
 263                 case PM_SUSPEND_MEM:
 264                         suspend_state = &constraints->state_mem;
 265                         break;
 266                 case PM_SUSPEND_MAX:
 267                         suspend_state = &constraints->state_disk;
 268                         break;
 269                 case PM_SUSPEND_STANDBY:
 270                         suspend_state = &constraints->state_standby;
 271                         break;
 272                 case PM_SUSPEND_ON:
 273                 case PM_SUSPEND_TO_IDLE:
 274                 default:
 275                         continue;
 276                 }
 277
 278                 suspend_np = of_get_child_by_name(np, regulator_states[i]);
 279                 if (!suspend_np)
 280                         continue;
 281                 if (!suspend_state) {
 282                         of_node_put(suspend_np);
 283                         continue;
 284                 }
 285
 286                 if (!of_property_read_u32(suspend_np, "regulator-mode",
 287                                           &pval)) {
 288                         if (desc && desc->of_map_mode) {
 289                                 mode = desc->of_map_mode(pval);
 290                                 if (mode == REGULATOR_MODE_INVALID)
 291                                         pr_err("%pOFn: invalid mode %u\n",
 292                                                np, pval);
 293                                 else
 294                                         suspend_state->mode = mode;
 295                         } else {
 296                                 pr_warn("%pOFn: mapping for mode %d not defined\n",
 297                                         np, pval);
 298                         }
 299                 }
 300
 301                 if (of_property_read_bool(suspend_np,
 302                                         "regulator-on-in-suspend"))
 303                         suspend_state->enabled = ENABLE_IN_SUSPEND;
 304                 else if (of_property_read_bool(suspend_np,
 305                                         "regulator-off-in-suspend"))
 306                         suspend_state->enabled = DISABLE_IN_SUSPEND;
 307
 308                 if (!of_property_read_u32(suspend_np,
 309                                 "regulator-suspend-min-microvolt", &pval))
 310                         suspend_state->min_uV = pval;
 311
 312                 if (!of_property_read_u32(suspend_np,
 313                                 "regulator-suspend-max-microvolt", &pval))
 314                         suspend_state->max_uV = pval;
 315
 316                 if (!of_property_read_u32(suspend_np,
 317                                         "regulator-suspend-microvolt", &pval))
 318                         suspend_state->uV = pval;
 319                 else /* otherwise use min_uV as default suspend voltage */
 320                         suspend_state->uV = suspend_state->min_uV;
 321
 322                 if (of_property_read_bool(suspend_np,
 323                                         "regulator-changeable-in-suspend"))
 324                         suspend_state->changeable = true;
 325
 326                 if (i == PM_SUSPEND_MEM)
 327                         constraints->initial_state = PM_SUSPEND_MEM;
 328
 329                 of_node_put(suspend_np);
 330                 suspend_state = NULL;
 331                 suspend_np = NULL;
 332         }
 333
 334         return 0;
 335 }
 336
 337 /**
 338  * of_get_regulator_init_data - extract regulator_init_data structure info
 339  * @dev: device requesting for regulator_init_data
 340  * @node: regulator device node
 341  * @desc: regulator description
 342  *
 343  * Populates regulator_init_data structure by extracting data from device
 344  * tree node.
 345  *
 346  * Return: Pointer to a populated &struct regulator_init_data or NULL if
 347  *         memory allocation fails.
 348  */
 349 struct regulator_init_data *of_get_regulator_init_data(struct device *dev,
 350                                           struct device_node *node,
 351                                           const struct regulator_desc *desc)
 352 {
 353         struct regulator_init_data *init_data;
 354
 355         if (!node)
 356                 return NULL;
 357
 358         init_data = devm_kzalloc(dev, sizeof(*init_data), GFP_KERNEL);
 359         if (!init_data)
 360                 return NULL; /* Out of memory? */
 361
 362         if (of_get_regulation_constraints(dev, node, &init_data, desc))
 363                 return NULL;
 364
 365         return init_data;
 366 }
 367 EXPORT_SYMBOL_GPL(of_get_regulator_init_data);
 368
 369 struct devm_of_regulator_matches {
 370         struct of_regulator_match *matches;
 371         unsigned int num_matches;
 372 };
 373
 374 static void devm_of_regulator_put_matches(struct device *dev, void *res)
 375 {
 376         struct devm_of_regulator_matches *devm_matches = res;
 377         int i;
 378
 379         for (i = 0; i < devm_matches->num_matches; i++)
 380                 of_node_put(devm_matches->matches[i].of_node);
 381 }
 382
 383 /**
 384  * of_regulator_match - extract multiple regulator init data from device tree.
 385  * @dev: device requesting the data
 386  * @node: parent device node of the regulators
 387  * @matches: match table for the regulators
 388  * @num_matches: number of entries in match table
 389  *
 390  * This function uses a match table specified by the regulator driver to
 391  * parse regulator init data from the device tree. @node is expected to
 392  * contain a set of child nodes, each providing the init data for one
 393  * regulator. The data parsed from a child node will be matched to a regulator
 394  * based on either the deprecated property regulator-compatible if present,
 395  * or otherwise the child node's name. Note that the match table is modified
 396  * in place and an additional of_node reference is taken for each matched
 397  * regulator.
 398  *
 399  * Return: The number of matches found or a negative error number on failure.
 400  */
 401 int of_regulator_match(struct device *dev, struct device_node *node,
 402                        struct of_regulator_match *matches,
 403                        unsigned int num_matches)
 404 {
 405         unsigned int count = 0;
 406         unsigned int i;
 407         const char *name;
 408         struct device_node *child;
 409         struct devm_of_regulator_matches *devm_matches;
 410
 411         if (!dev || !node)
 412                 return -EINVAL;
 413
 414         devm_matches = devres_alloc(devm_of_regulator_put_matches,
 415                                     sizeof(struct devm_of_regulator_matches),
 416                                     GFP_KERNEL);
 417         if (!devm_matches)
 418                 return -ENOMEM;
 419
 420         devm_matches->matches = matches;
 421         devm_matches->num_matches = num_matches;
 422
 423         devres_add(dev, devm_matches);
 424
 425         for (i = 0; i < num_matches; i++) {
 426                 struct of_regulator_match *match = &matches[i];
 427                 match->init_data = NULL;
 428                 match->of_node = NULL;
 429         }
 430
 431         for_each_child_of_node(node, child) {
 432                 name = of_get_property(child,
 433                                         "regulator-compatible", NULL);
 434                 if (!name)
 435                         name = child->name;
 436                 for (i = 0; i < num_matches; i++) {
 437                         struct of_regulator_match *match = &matches[i];
 438                         if (match->of_node)
 439                                 continue;
 440
 441                         if (strcmp(match->name, name))
 442                                 continue;
 443
 444                         match->init_data =
 445                                 of_get_regulator_init_data(dev, child,
 446                                                            match->desc);
 447                         if (!match->init_data) {
 448                                 dev_err(dev,
 449                                         "failed to parse DT for regulator %pOFn\n",
 450                                         child);
 451                                 of_node_put(child);
 452                                 goto err_put;
 453                         }
 454                         match->of_node = of_node_get(child);
 455                         count++;
 456                         break;
 457                 }
 458         }
 459
 460         return count;
 461
 462 err_put:
 463         for (i = 0; i < num_matches; i++) {
 464                 struct of_regulator_match *match = &matches[i];
 465
 466                 match->init_data = NULL;
 467                 if (match->of_node) {
 468                         of_node_put(match->of_node);
 469                         match->of_node = NULL;
 470                 }
 471         }
 472         return -EINVAL;
 473 }
 474 EXPORT_SYMBOL_GPL(of_regulator_match);
 475
 476 static struct
 477 device_node *regulator_of_get_init_node(struct device *dev,
 478                                         const struct regulator_desc *desc)
 479 {
 480         struct device_node *search, *child;
 481         const char *name;
 482
 483         if (!dev->of_node || !desc->of_match)
 484                 return NULL;
 485
 486         if (desc->regulators_node) {
 487                 search = of_get_child_by_name(dev->of_node,
 488                                               desc->regulators_node);
 489         } else {
 490                 search = of_node_get(dev->of_node);
 491
 492                 if (!strcmp(desc->of_match, search->name))
 493                         return search;
 494         }
 495
 496         if (!search) {
 497                 dev_dbg(dev, "Failed to find regulator container node '%s'\n",
 498                         desc->regulators_node);
 499                 return NULL;
 500         }
 501
 502         for_each_available_child_of_node(search, child) {
 503                 name = of_get_property(child, "regulator-compatible", NULL);
 504                 if (!name) {
 505                         if (!desc->of_match_full_name)
 506                                 name = child->name;
 507                         else
 508                                 name = child->full_name;
 509                 }
 510
 511                 if (!strcmp(desc->of_match, name)) {
 512                         of_node_put(search);
 513                         /*
 514                          * 'of_node_get(child)' is already performed by the
 515                          * for_each loop.
 516                          */
 517                         return child;
 518                 }
 519         }
 520
 521         of_node_put(search);
 522
 523         return NULL;
 524 }
 525
 526 struct regulator_init_data *regulator_of_get_init_data(struct device *dev,
 527                                             const struct regulator_desc *desc,
 528                                             struct regulator_config *config,
 529                                             struct device_node **node)
 530 {
 531         struct device_node *child;
 532         struct regulator_init_data *init_data = NULL;
 533
 534         child = regulator_of_get_init_node(config->dev, desc);
 535         if (!child)
 536                 return NULL;
 537
 538         init_data = of_get_regulator_init_data(dev, child, desc);
 539         if (!init_data) {
 540                 dev_err(dev, "failed to parse DT for regulator %pOFn\n", child);
 541                 goto error;
 542         }
 543
 544         if (desc->of_parse_cb) {
 545                 int ret;
 546
 547                 ret = desc->of_parse_cb(child, desc, config);
 548                 if (ret) {
 549                         if (ret == -EPROBE_DEFER) {
 550                                 of_node_put(child);
 551                                 return ERR_PTR(-EPROBE_DEFER);
 552                         }
 553                         dev_err(dev,
 554                                 "driver callback failed to parse DT for regulator %pOFn\n",
 555                                 child);
 556                         goto error;
 557                 }
 558         }
 559
 560         *node = child;
 561
 562         return init_data;
 563
 564 error:
 565         of_node_put(child);
 566
 567         return NULL;
 568 }
 569
 570 /**
 571  * of_get_child_regulator - get a child regulator device node
 572  * based on supply name
 573  * @parent: Parent device node
 574  * @prop_name: Combination regulator supply name and "-supply"
 575  *
 576  * Traverse all child nodes.
 577  * Extract the child regulator device node corresponding to the supply name.
 578  *
 579  * Return: Pointer to the &struct device_node corresponding to the regulator
 580  *         if found, or %NULL if not found.
 581  */
 582 static struct device_node *of_get_child_regulator(struct device_node *parent,
 583                                                   const char *prop_name)
 584 {
 585         struct device_node *regnode = NULL;
 586         struct device_node *child = NULL;
 587
 588         for_each_child_of_node(parent, child) {
 589                 regnode = of_parse_phandle(child, prop_name, 0);
 590                 if (regnode)
 591                         goto err_node_put;
 592
 593                 regnode = of_get_child_regulator(child, prop_name);
 594                 if (regnode)
 595                         goto err_node_put;
 596         }
 597         return NULL;
 598
 599 err_node_put:
 600         of_node_put(child);
 601         return regnode;
 602 }
 603
 604 /**
 605  * of_get_regulator - get a regulator device node based on supply name
 606  * @dev: Device pointer for dev_printk() messages
 607  * @node: Device node pointer for supply property lookup
 608  * @supply: regulator supply name
 609  *
 610  * Extract the regulator device node corresponding to the supply name.
 611  *
 612  * Return: Pointer to the &struct device_node corresponding to the regulator
 613  *         if found, or %NULL if not found.
 614  */
 615 static struct device_node *of_get_regulator(struct device *dev, struct device_node *node,
 616                                             const char *supply)
 617 {
 618         struct device_node *regnode = NULL;
 619         char prop_name[64]; /* 64 is max size of property name */
 620
 621         dev_dbg(dev, "Looking up %s-supply from device node %pOF\n", supply, node);
 622
 623         snprintf(prop_name, 64, "%s-supply", supply);
 624         regnode = of_parse_phandle(node, prop_name, 0);
 625         if (regnode)
 626                 return regnode;
 627
 628         regnode = of_get_child_regulator(dev->of_node, prop_name);
 629         if (regnode)
 630                 return regnode;
 631
 632         dev_dbg(dev, "Looking up %s property in node %pOF failed\n", prop_name, dev->of_node);
 633         return NULL;
 634 }
 635
 636 static struct regulator_dev *of_find_regulator_by_node(struct device_node *np)
 637 {
 638         struct device *dev;
 639
 640         dev = class_find_device_by_of_node(&regulator_class, np);
 641
 642         return dev ? dev_to_rdev(dev) : NULL;
 643 }
 644
 645 /**
 646  * of_regulator_dev_lookup - lookup a regulator device with device tree only
 647  * @dev: Device pointer for regulator supply lookup.
 648  * @np: Device node pointer for regulator supply lookup.
 649  * @supply: Supply name or regulator ID.
 650  *
 651  * Return: Pointer to the &struct regulator_dev on success, or ERR_PTR()
 652  *         encoded value on error.
 653  *
 654  * If successful, returns a pointer to the &struct regulator_dev that
 655  * corresponds to the name @supply and with the embedded &struct device
 656  * refcount incremented by one. The refcount must be dropped by calling
 657  * put_device().
 658  *
 659  * On failure one of the following ERR_PTR() encoded values is returned:
 660  * * -%ENODEV if lookup fails permanently.
 661  * * -%EPROBE_DEFER if lookup could succeed in the future.
 662  */
 663 struct regulator_dev *of_regulator_dev_lookup(struct device *dev, struct device_node *np,
 664                                               const char *supply)
 665 {
 666         struct regulator_dev *r;
 667         struct device_node *node;
 668
 669         node = of_get_regulator(dev, np, supply);
 670         if (node) {
 671                 r = of_find_regulator_by_node(node);
 672                 of_node_put(node);
 673                 if (r)
 674                         return r;
 675
 676                 /*
 677                  * We have a node, but there is no device.
 678                  * assume it has not registered yet.
 679                  */
 680                 return ERR_PTR(-EPROBE_DEFER);
 681         }
 682
 683         return ERR_PTR(-ENODEV);
 684 }
 685
 686 struct regulator *_of_regulator_get(struct device *dev, struct device_node *node,
 687                                     const char *id, enum regulator_get_type get_type)
 688 {
 689         struct regulator_dev *r;
 690         int ret;
 691
 692         ret = _regulator_get_common_check(dev, id, get_type);
 693         if (ret)
 694                 return ERR_PTR(ret);
 695
 696         r = of_regulator_dev_lookup(dev, node, id);
 697         return _regulator_get_common(r, dev, id, get_type);
 698 }
 699
 700 /**
 701  * of_regulator_get - get regulator via device tree lookup
 702  * @dev: device used for dev_printk() messages
 703  * @node: device node for regulator "consumer"
 704  * @id: Supply name
 705  *
 706  * Return: pointer to struct regulator corresponding to the regulator producer,
 707  *         or PTR_ERR() encoded error number.
 708  *
 709  * This is intended for use by consumers that want to get a regulator
 710  * supply directly from a device node. This will _not_ consider supply
 711  * aliases. See regulator_dev_lookup().
 712  */
 713 struct regulator *of_regulator_get(struct device *dev,
 714                                             struct device_node *node,
 715                                             const char *id)
 716 {
 717         return _of_regulator_get(dev, node, id, NORMAL_GET);
 718 }
 719 EXPORT_SYMBOL_GPL(of_regulator_get);
 720
 721 /**
 722  * of_regulator_get_optional - get optional regulator via device tree lookup
 723  * @dev: device used for dev_printk() messages
 724  * @node: device node for regulator "consumer"
 725  * @id: Supply name
 726  *
 727  * Return: pointer to struct regulator corresponding to the regulator producer,
 728  *         or PTR_ERR() encoded error number.
 729  *
 730  * This is intended for use by consumers that want to get a regulator
 731  * supply directly from a device node, and can and want to deal with
 732  * absence of such supplies. This will _not_ consider supply aliases.
 733  * See regulator_dev_lookup().
 734  */
 735 struct regulator *of_regulator_get_optional(struct device *dev,
 736                                             struct device_node *node,
 737                                             const char *id)
 738 {
 739         return _of_regulator_get(dev, node, id, OPTIONAL_GET);
 740 }
 741 EXPORT_SYMBOL_GPL(of_regulator_get_optional);
 742
 743 /*
 744  * Returns number of regulators coupled with rdev.
 745  */
 746 int of_get_n_coupled(struct regulator_dev *rdev)
 747 {
 748         struct device_node *node = rdev->dev.of_node;
 749         int n_phandles;
 750
 751         n_phandles = of_count_phandle_with_args(node,
 752                                                 "regulator-coupled-with",
 753                                                 NULL);
 754
 755         return (n_phandles > 0) ? n_phandles : 0;
 756 }
 757
 758 /* Looks for "to_find" device_node in src's "regulator-coupled-with" property */
 759 static bool of_coupling_find_node(struct device_node *src,
 760                                   struct device_node *to_find,
 761                                   int *index)
 762 {
 763         int n_phandles, i;
 764         bool found = false;
 765
 766         n_phandles = of_count_phandle_with_args(src,
 767                                                 "regulator-coupled-with",
 768                                                 NULL);
 769
 770         for (i = 0; i < n_phandles; i++) {
 771                 struct device_node *tmp = of_parse_phandle(src,
 772                                            "regulator-coupled-with", i);
 773
 774                 if (!tmp)
 775                         break;
 776
 777                 /* found */
 778                 if (tmp == to_find)
 779                         found = true;
 780
 781                 of_node_put(tmp);
 782
 783                 if (found) {
 784                         *index = i;
 785                         break;
 786                 }
 787         }
 788
 789         return found;
 790 }
 791
 792 /**
 793  * of_check_coupling_data - Parse rdev's coupling properties and check data
 794  *                          consistency
 795  * @rdev: pointer to regulator_dev whose data is checked
 796  *
 797  * Function checks if all the following conditions are met:
 798  * - rdev's max_spread is greater than 0
 799  * - all coupled regulators have the same max_spread
 800  * - all coupled regulators have the same number of regulator_dev phandles
 801  * - all regulators are linked to each other
 802  *
 803  * Return: True if all conditions are met; false otherwise.
 804  */
 805 bool of_check_coupling_data(struct regulator_dev *rdev)
 806 {
 807         struct device_node *node = rdev->dev.of_node;
 808         int n_phandles = of_get_n_coupled(rdev);
 809         struct device_node *c_node;
 810         int index;
 811         int i;
 812         bool ret = true;
 813
 814         /* iterate over rdev's phandles */
 815         for (i = 0; i < n_phandles; i++) {
 816                 int max_spread = rdev->constraints->max_spread[i];
 817                 int c_max_spread, c_n_phandles;
 818
 819                 if (max_spread <= 0) {
 820                         dev_err(&rdev->dev, "max_spread value invalid\n");
 821                         return false;
 822                 }
 823
 824                 c_node = of_parse_phandle(node,
 825                                           "regulator-coupled-with", i);
 826
 827                 if (!c_node)
 828                         ret = false;
 829
 830                 c_n_phandles = of_count_phandle_with_args(c_node,
 831                                                           "regulator-coupled-with",
 832                                                           NULL);
 833
 834                 if (c_n_phandles != n_phandles) {
 835                         dev_err(&rdev->dev, "number of coupled reg phandles mismatch\n");
 836                         ret = false;
 837                         goto clean;
 838                 }
 839
 840                 if (!of_coupling_find_node(c_node, node, &index)) {
 841                         dev_err(&rdev->dev, "missing 2-way linking for coupled regulators\n");
 842                         ret = false;
 843                         goto clean;
 844                 }
 845
 846                 if (of_property_read_u32_index(c_node, "regulator-coupled-max-spread",
 847                                                index, &c_max_spread)) {
 848                         ret = false;
 849                         goto clean;
 850                 }
 851
 852                 if (c_max_spread != max_spread) {
 853                         dev_err(&rdev->dev,
 854                                 "coupled regulators max_spread mismatch\n");
 855                         ret = false;
 856                         goto clean;
 857                 }
 858
 859 clean:
 860                 of_node_put(c_node);
 861                 if (!ret)
 862                         break;
 863         }
 864
 865         return ret;
 866 }
 867
 868 /**
 869  * of_parse_coupled_regulator() - Get regulator_dev pointer from rdev's property
 870  * @rdev: Pointer to regulator_dev, whose DTS is used as a source to parse
 871  *        "regulator-coupled-with" property
 872  * @index: Index in phandles array
 873  *
 874  * Return: Pointer to the &struct regulator_dev parsed from DTS, or %NULL if
 875  *         it has not yet been registered.
 876  */
 877 struct regulator_dev *of_parse_coupled_regulator(struct regulator_dev *rdev,
 878                                                  int index)
 879 {
 880         struct device_node *node = rdev->dev.of_node;
 881         struct device_node *c_node;
 882         struct regulator_dev *c_rdev;
 883
 884         c_node = of_parse_phandle(node, "regulator-coupled-with", index);
 885         if (!c_node)
 886                 return NULL;
 887
 888         c_rdev = of_find_regulator_by_node(c_node);
 889
 890         of_node_put(c_node);
 891
 892         return c_rdev;
 893 }
 894
 895 /*
 896  * Check if name is a supply name according to the '*-supply' pattern
 897  * return 0 if false
 898  * return length of supply name without the -supply
 899  */
 900 static int is_supply_name(const char *name)
 901 {
 902         int strs, i;
 903
 904         strs = strlen(name);
 905         /* string need to be at minimum len(x-supply) */
 906         if (strs < 8)
 907                 return 0;
 908         for (i = strs - 6; i > 0; i--) {
 909                 /* find first '-' and check if right part is supply */
 910                 if (name[i] != '-')
 911                         continue;
 912                 if (strcmp(name + i + 1, "supply") != 0)
 913                         return 0;
 914                 return i;
 915         }
 916         return 0;
 917 }
 918
 919 /**
 920  * of_regulator_bulk_get_all - get multiple regulator consumers
 921  *
 922  * @dev:        Device to supply
 923  * @np:         device node to search for consumers
 924  * @consumers:  Configuration of consumers; clients are stored here.
 925  *
 926  * This helper function allows drivers to get several regulator
 927  * consumers in one operation.  If any of the regulators cannot be
 928  * acquired then any regulators that were allocated will be freed
 929  * before returning to the caller, and @consumers will not be
 930  * changed.
 931  *
 932  * Return: Number of regulators on success, or a negative error number
 933  *         on failure.
 934  */
 935 int of_regulator_bulk_get_all(struct device *dev, struct device_node *np,
 936                               struct regulator_bulk_data **consumers)
 937 {
 938         int num_consumers = 0;
 939         struct regulator *tmp;
 940         struct regulator_bulk_data *_consumers = NULL;
 941         struct property *prop;
 942         int i, n = 0, ret;
 943         char name[64];
 944
 945         /*
 946          * first pass: get numbers of xxx-supply
 947          * second pass: fill consumers
 948          */
 949 restart:
 950         for_each_property_of_node(np, prop) {
 951                 i = is_supply_name(prop->name);
 952                 if (i == 0)
 953                         continue;
 954                 if (!_consumers) {
 955                         num_consumers++;
 956                         continue;
 957                 } else {
 958                         memcpy(name, prop->name, i);
 959                         name[i] = '\0';
 960                         tmp = regulator_get(dev, name);
 961                         if (IS_ERR(tmp)) {
 962                                 ret = PTR_ERR(tmp);
 963                                 goto error;
 964                         }
 965                         _consumers[n].consumer = tmp;
 966                         n++;
 967                         continue;
 968                 }
 969         }
 970         if (_consumers) {
 971                 *consumers = _consumers;
 972                 return num_consumers;
 973         }
 974         if (num_consumers == 0)
 975                 return 0;
 976         _consumers = kmalloc_array(num_consumers,
 977                                    sizeof(struct regulator_bulk_data),
 978                                    GFP_KERNEL);
 979         if (!_consumers)
 980                 return -ENOMEM;
 981         goto restart;
 982
 983 error:
 984         while (--n >= 0)
 985                 regulator_put(_consumers[n].consumer);
 986         kfree(_consumers);
 987         return ret;
 988 }
 989 EXPORT_SYMBOL_GPL(of_regulator_bulk_get_all);