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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * OF helpers for regulator framework4 *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 18static 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 24static void fill_limit(int *limit, int val)25{26	if (val)27		if (val == 1)28			*limit = REGULATOR_NOTIF_LIMIT_ENABLE;29		else30			*limit = val;31	else32		*limit = REGULATOR_NOTIF_LIMIT_DISABLE;33}34 35static 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 80static 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	constraints->boot_on = of_property_read_bool(np, "regulator-boot-on");129	constraints->always_on = of_property_read_bool(np, "regulator-always-on");130	if (!constraints->always_on) /* status change should be possible. */131		constraints->valid_ops_mask |= REGULATOR_CHANGE_STATUS;132 133	constraints->pull_down = of_property_read_bool(np, "regulator-pull-down");134	constraints->system_critical = of_property_read_bool(np,135						"system-critical-regulator");136 137	if (of_property_read_bool(np, "regulator-allow-bypass"))138		constraints->valid_ops_mask |= REGULATOR_CHANGE_BYPASS;139 140	if (of_property_read_bool(np, "regulator-allow-set-load"))141		constraints->valid_ops_mask |= REGULATOR_CHANGE_DRMS;142 143	ret = of_property_read_u32(np, "regulator-ramp-delay", &pval);144	if (!ret) {145		if (pval)146			constraints->ramp_delay = pval;147		else148			constraints->ramp_disable = true;149	}150 151	ret = of_property_read_u32(np, "regulator-settling-time-us", &pval);152	if (!ret)153		constraints->settling_time = pval;154 155	ret = of_property_read_u32(np, "regulator-settling-time-up-us", &pval);156	if (!ret)157		constraints->settling_time_up = pval;158	if (constraints->settling_time_up && constraints->settling_time) {159		pr_warn("%pOFn: ambiguous configuration for settling time, ignoring 'regulator-settling-time-up-us'\n",160			np);161		constraints->settling_time_up = 0;162	}163 164	ret = of_property_read_u32(np, "regulator-settling-time-down-us",165				   &pval);166	if (!ret)167		constraints->settling_time_down = pval;168	if (constraints->settling_time_down && constraints->settling_time) {169		pr_warn("%pOFn: ambiguous configuration for settling time, ignoring 'regulator-settling-time-down-us'\n",170			np);171		constraints->settling_time_down = 0;172	}173 174	ret = of_property_read_u32(np, "regulator-enable-ramp-delay", &pval);175	if (!ret)176		constraints->enable_time = pval;177 178	ret = of_property_read_u32(np, "regulator-uv-survival-time-ms", &pval);179	if (!ret)180		constraints->uv_less_critical_window_ms = pval;181	else182		constraints->uv_less_critical_window_ms =183				REGULATOR_DEF_UV_LESS_CRITICAL_WINDOW_MS;184 185	constraints->soft_start = of_property_read_bool(np,186					"regulator-soft-start");187	ret = of_property_read_u32(np, "regulator-active-discharge", &pval);188	if (!ret) {189		constraints->active_discharge =190				(pval) ? REGULATOR_ACTIVE_DISCHARGE_ENABLE :191					REGULATOR_ACTIVE_DISCHARGE_DISABLE;192	}193 194	if (!of_property_read_u32(np, "regulator-initial-mode", &pval)) {195		if (desc && desc->of_map_mode) {196			mode = desc->of_map_mode(pval);197			if (mode == REGULATOR_MODE_INVALID)198				pr_err("%pOFn: invalid mode %u\n", np, pval);199			else200				constraints->initial_mode = mode;201		} else {202			pr_warn("%pOFn: mapping for mode %d not defined\n",203				np, pval);204		}205	}206 207	len = of_property_count_elems_of_size(np, "regulator-allowed-modes",208						sizeof(u32));209	if (len > 0) {210		if (desc && desc->of_map_mode) {211			for (i = 0; i < len; i++) {212				ret = of_property_read_u32_index(np,213					"regulator-allowed-modes", i, &pval);214				if (ret) {215					pr_err("%pOFn: couldn't read allowed modes index %d, ret=%d\n",216						np, i, ret);217					break;218				}219				mode = desc->of_map_mode(pval);220				if (mode == REGULATOR_MODE_INVALID)221					pr_err("%pOFn: invalid regulator-allowed-modes element %u\n",222						np, pval);223				else224					constraints->valid_modes_mask |= mode;225			}226			if (constraints->valid_modes_mask)227				constraints->valid_ops_mask228					|= REGULATOR_CHANGE_MODE;229		} else {230			pr_warn("%pOFn: mode mapping not defined\n", np);231		}232	}233 234	if (!of_property_read_u32(np, "regulator-system-load", &pval))235		constraints->system_load = pval;236 237	if (n_phandles) {238		constraints->max_spread = devm_kzalloc(dev,239				sizeof(*constraints->max_spread) * n_phandles,240				GFP_KERNEL);241 242		if (!constraints->max_spread)243			return -ENOMEM;244 245		of_property_read_u32_array(np, "regulator-coupled-max-spread",246					   constraints->max_spread, n_phandles);247	}248 249	if (!of_property_read_u32(np, "regulator-max-step-microvolt",250				  &pval))251		constraints->max_uV_step = pval;252 253	constraints->over_current_protection = of_property_read_bool(np,254					"regulator-over-current-protection");255 256	of_get_regulator_prot_limits(np, constraints);257 258	for (i = 0; i < ARRAY_SIZE(regulator_states); i++) {259		switch (i) {260		case PM_SUSPEND_MEM:261			suspend_state = &constraints->state_mem;262			break;263		case PM_SUSPEND_MAX:264			suspend_state = &constraints->state_disk;265			break;266		case PM_SUSPEND_STANDBY:267			suspend_state = &constraints->state_standby;268			break;269		case PM_SUSPEND_ON:270		case PM_SUSPEND_TO_IDLE:271		default:272			continue;273		}274 275		suspend_np = of_get_child_by_name(np, regulator_states[i]);276		if (!suspend_np)277			continue;278		if (!suspend_state) {279			of_node_put(suspend_np);280			continue;281		}282 283		if (!of_property_read_u32(suspend_np, "regulator-mode",284					  &pval)) {285			if (desc && desc->of_map_mode) {286				mode = desc->of_map_mode(pval);287				if (mode == REGULATOR_MODE_INVALID)288					pr_err("%pOFn: invalid mode %u\n",289					       np, pval);290				else291					suspend_state->mode = mode;292			} else {293				pr_warn("%pOFn: mapping for mode %d not defined\n",294					np, pval);295			}296		}297 298		if (of_property_read_bool(suspend_np,299					"regulator-on-in-suspend"))300			suspend_state->enabled = ENABLE_IN_SUSPEND;301		else if (of_property_read_bool(suspend_np,302					"regulator-off-in-suspend"))303			suspend_state->enabled = DISABLE_IN_SUSPEND;304 305		if (!of_property_read_u32(suspend_np,306				"regulator-suspend-min-microvolt", &pval))307			suspend_state->min_uV = pval;308 309		if (!of_property_read_u32(suspend_np,310				"regulator-suspend-max-microvolt", &pval))311			suspend_state->max_uV = pval;312 313		if (!of_property_read_u32(suspend_np,314					"regulator-suspend-microvolt", &pval))315			suspend_state->uV = pval;316		else /* otherwise use min_uV as default suspend voltage */317			suspend_state->uV = suspend_state->min_uV;318 319		if (of_property_read_bool(suspend_np,320					"regulator-changeable-in-suspend"))321			suspend_state->changeable = true;322 323		if (i == PM_SUSPEND_MEM)324			constraints->initial_state = PM_SUSPEND_MEM;325 326		of_node_put(suspend_np);327		suspend_state = NULL;328		suspend_np = NULL;329	}330 331	return 0;332}333 334/**335 * of_get_regulator_init_data - extract regulator_init_data structure info336 * @dev: device requesting for regulator_init_data337 * @node: regulator device node338 * @desc: regulator description339 *340 * Populates regulator_init_data structure by extracting data from device341 * tree node.342 *343 * Return: Pointer to a populated &struct regulator_init_data or NULL if344 *	   memory allocation fails.345 */346struct regulator_init_data *of_get_regulator_init_data(struct device *dev,347					  struct device_node *node,348					  const struct regulator_desc *desc)349{350	struct regulator_init_data *init_data;351 352	if (!node)353		return NULL;354 355	init_data = devm_kzalloc(dev, sizeof(*init_data), GFP_KERNEL);356	if (!init_data)357		return NULL; /* Out of memory? */358 359	if (of_get_regulation_constraints(dev, node, &init_data, desc))360		return NULL;361 362	return init_data;363}364EXPORT_SYMBOL_GPL(of_get_regulator_init_data);365 366struct devm_of_regulator_matches {367	struct of_regulator_match *matches;368	unsigned int num_matches;369};370 371static void devm_of_regulator_put_matches(struct device *dev, void *res)372{373	struct devm_of_regulator_matches *devm_matches = res;374	int i;375 376	for (i = 0; i < devm_matches->num_matches; i++)377		of_node_put(devm_matches->matches[i].of_node);378}379 380/**381 * of_regulator_match - extract multiple regulator init data from device tree.382 * @dev: device requesting the data383 * @node: parent device node of the regulators384 * @matches: match table for the regulators385 * @num_matches: number of entries in match table386 *387 * This function uses a match table specified by the regulator driver to388 * parse regulator init data from the device tree. @node is expected to389 * contain a set of child nodes, each providing the init data for one390 * regulator. The data parsed from a child node will be matched to a regulator391 * based on either the deprecated property regulator-compatible if present,392 * or otherwise the child node's name. Note that the match table is modified393 * in place and an additional of_node reference is taken for each matched394 * regulator.395 *396 * Return: The number of matches found or a negative error number on failure.397 */398int of_regulator_match(struct device *dev, struct device_node *node,399		       struct of_regulator_match *matches,400		       unsigned int num_matches)401{402	unsigned int count = 0;403	unsigned int i;404	const char *name;405	struct device_node *child;406	struct devm_of_regulator_matches *devm_matches;407 408	if (!dev || !node)409		return -EINVAL;410 411	devm_matches = devres_alloc(devm_of_regulator_put_matches,412				    sizeof(struct devm_of_regulator_matches),413				    GFP_KERNEL);414	if (!devm_matches)415		return -ENOMEM;416 417	devm_matches->matches = matches;418	devm_matches->num_matches = num_matches;419 420	devres_add(dev, devm_matches);421 422	for (i = 0; i < num_matches; i++) {423		struct of_regulator_match *match = &matches[i];424		match->init_data = NULL;425		match->of_node = NULL;426	}427 428	for_each_child_of_node(node, child) {429		name = of_get_property(child,430					"regulator-compatible", NULL);431		if (!name)432			name = child->name;433		for (i = 0; i < num_matches; i++) {434			struct of_regulator_match *match = &matches[i];435			if (match->of_node)436				continue;437 438			if (strcmp(match->name, name))439				continue;440 441			match->init_data =442				of_get_regulator_init_data(dev, child,443							   match->desc);444			if (!match->init_data) {445				dev_err(dev,446					"failed to parse DT for regulator %pOFn\n",447					child);448				of_node_put(child);449				return -EINVAL;450			}451			match->of_node = of_node_get(child);452			count++;453			break;454		}455	}456 457	return count;458}459EXPORT_SYMBOL_GPL(of_regulator_match);460 461static struct462device_node *regulator_of_get_init_node(struct device *dev,463					const struct regulator_desc *desc)464{465	struct device_node *search, *child;466	const char *name;467 468	if (!dev->of_node || !desc->of_match)469		return NULL;470 471	if (desc->regulators_node) {472		search = of_get_child_by_name(dev->of_node,473					      desc->regulators_node);474	} else {475		search = of_node_get(dev->of_node);476 477		if (!strcmp(desc->of_match, search->name))478			return search;479	}480 481	if (!search) {482		dev_dbg(dev, "Failed to find regulator container node '%s'\n",483			desc->regulators_node);484		return NULL;485	}486 487	for_each_available_child_of_node(search, child) {488		name = of_get_property(child, "regulator-compatible", NULL);489		if (!name) {490			if (!desc->of_match_full_name)491				name = child->name;492			else493				name = child->full_name;494		}495 496		if (!strcmp(desc->of_match, name)) {497			of_node_put(search);498			/*499			 * 'of_node_get(child)' is already performed by the500			 * for_each loop.501			 */502			return child;503		}504	}505 506	of_node_put(search);507 508	return NULL;509}510 511struct regulator_init_data *regulator_of_get_init_data(struct device *dev,512					    const struct regulator_desc *desc,513					    struct regulator_config *config,514					    struct device_node **node)515{516	struct device_node *child;517	struct regulator_init_data *init_data = NULL;518 519	child = regulator_of_get_init_node(config->dev, desc);520	if (!child)521		return NULL;522 523	init_data = of_get_regulator_init_data(dev, child, desc);524	if (!init_data) {525		dev_err(dev, "failed to parse DT for regulator %pOFn\n", child);526		goto error;527	}528 529	if (desc->of_parse_cb) {530		int ret;531 532		ret = desc->of_parse_cb(child, desc, config);533		if (ret) {534			if (ret == -EPROBE_DEFER) {535				of_node_put(child);536				return ERR_PTR(-EPROBE_DEFER);537			}538			dev_err(dev,539				"driver callback failed to parse DT for regulator %pOFn\n",540				child);541			goto error;542		}543	}544 545	*node = child;546 547	return init_data;548 549error:550	of_node_put(child);551 552	return NULL;553}554 555/**556 * of_get_child_regulator - get a child regulator device node557 * based on supply name558 * @parent: Parent device node559 * @prop_name: Combination regulator supply name and "-supply"560 *561 * Traverse all child nodes.562 * Extract the child regulator device node corresponding to the supply name.563 *564 * Return: Pointer to the &struct device_node corresponding to the regulator565 *	   if found, or %NULL if not found.566 */567static struct device_node *of_get_child_regulator(struct device_node *parent,568						  const char *prop_name)569{570	struct device_node *regnode = NULL;571	struct device_node *child = NULL;572 573	for_each_child_of_node(parent, child) {574		regnode = of_parse_phandle(child, prop_name, 0);575		if (regnode)576			goto err_node_put;577 578		regnode = of_get_child_regulator(child, prop_name);579		if (regnode)580			goto err_node_put;581	}582	return NULL;583 584err_node_put:585	of_node_put(child);586	return regnode;587}588 589/**590 * of_get_regulator - get a regulator device node based on supply name591 * @dev: Device pointer for the consumer (of regulator) device592 * @supply: regulator supply name593 *594 * Extract the regulator device node corresponding to the supply name.595 *596 * Return: Pointer to the &struct device_node corresponding to the regulator597 *	   if found, or %NULL if not found.598 */599static struct device_node *of_get_regulator(struct device *dev, const char *supply)600{601	struct device_node *regnode = NULL;602	char prop_name[64]; /* 64 is max size of property name */603 604	dev_dbg(dev, "Looking up %s-supply from device tree\n", supply);605 606	snprintf(prop_name, 64, "%s-supply", supply);607	regnode = of_parse_phandle(dev->of_node, prop_name, 0);608	if (regnode)609		return regnode;610 611	regnode = of_get_child_regulator(dev->of_node, prop_name);612	if (regnode)613		return regnode;614 615	dev_dbg(dev, "Looking up %s property in node %pOF failed\n", prop_name, dev->of_node);616	return NULL;617}618 619static struct regulator_dev *of_find_regulator_by_node(struct device_node *np)620{621	struct device *dev;622 623	dev = class_find_device_by_of_node(&regulator_class, np);624 625	return dev ? dev_to_rdev(dev) : NULL;626}627 628/**629 * of_regulator_dev_lookup - lookup a regulator device with device tree only630 * @dev: Device pointer for regulator supply lookup.631 * @supply: Supply name or regulator ID.632 *633 * Return: Pointer to the &struct regulator_dev on success, or ERR_PTR()634 *	   encoded value on error.635 *636 * If successful, returns a pointer to the &struct regulator_dev that637 * corresponds to the name @supply and with the embedded &struct device638 * refcount incremented by one. The refcount must be dropped by calling639 * put_device().640 *641 * On failure one of the following ERR_PTR() encoded values is returned:642 * * -%ENODEV if lookup fails permanently.643 * * -%EPROBE_DEFER if lookup could succeed in the future.644 */645struct regulator_dev *of_regulator_dev_lookup(struct device *dev,646					      const char *supply)647{648	struct regulator_dev *r;649	struct device_node *node;650 651	node = of_get_regulator(dev, supply);652	if (node) {653		r = of_find_regulator_by_node(node);654		of_node_put(node);655		if (r)656			return r;657 658		/*659		 * We have a node, but there is no device.660		 * assume it has not registered yet.661		 */662		return ERR_PTR(-EPROBE_DEFER);663	}664 665	return ERR_PTR(-ENODEV);666}667 668/*669 * Returns number of regulators coupled with rdev.670 */671int of_get_n_coupled(struct regulator_dev *rdev)672{673	struct device_node *node = rdev->dev.of_node;674	int n_phandles;675 676	n_phandles = of_count_phandle_with_args(node,677						"regulator-coupled-with",678						NULL);679 680	return (n_phandles > 0) ? n_phandles : 0;681}682 683/* Looks for "to_find" device_node in src's "regulator-coupled-with" property */684static bool of_coupling_find_node(struct device_node *src,685				  struct device_node *to_find,686				  int *index)687{688	int n_phandles, i;689	bool found = false;690 691	n_phandles = of_count_phandle_with_args(src,692						"regulator-coupled-with",693						NULL);694 695	for (i = 0; i < n_phandles; i++) {696		struct device_node *tmp = of_parse_phandle(src,697					   "regulator-coupled-with", i);698 699		if (!tmp)700			break;701 702		/* found */703		if (tmp == to_find)704			found = true;705 706		of_node_put(tmp);707 708		if (found) {709			*index = i;710			break;711		}712	}713 714	return found;715}716 717/**718 * of_check_coupling_data - Parse rdev's coupling properties and check data719 *			    consistency720 * @rdev: pointer to regulator_dev whose data is checked721 *722 * Function checks if all the following conditions are met:723 * - rdev's max_spread is greater than 0724 * - all coupled regulators have the same max_spread725 * - all coupled regulators have the same number of regulator_dev phandles726 * - all regulators are linked to each other727 *728 * Return: True if all conditions are met; false otherwise.729 */730bool of_check_coupling_data(struct regulator_dev *rdev)731{732	struct device_node *node = rdev->dev.of_node;733	int n_phandles = of_get_n_coupled(rdev);734	struct device_node *c_node;735	int index;736	int i;737	bool ret = true;738 739	/* iterate over rdev's phandles */740	for (i = 0; i < n_phandles; i++) {741		int max_spread = rdev->constraints->max_spread[i];742		int c_max_spread, c_n_phandles;743 744		if (max_spread <= 0) {745			dev_err(&rdev->dev, "max_spread value invalid\n");746			return false;747		}748 749		c_node = of_parse_phandle(node,750					  "regulator-coupled-with", i);751 752		if (!c_node)753			ret = false;754 755		c_n_phandles = of_count_phandle_with_args(c_node,756							  "regulator-coupled-with",757							  NULL);758 759		if (c_n_phandles != n_phandles) {760			dev_err(&rdev->dev, "number of coupled reg phandles mismatch\n");761			ret = false;762			goto clean;763		}764 765		if (!of_coupling_find_node(c_node, node, &index)) {766			dev_err(&rdev->dev, "missing 2-way linking for coupled regulators\n");767			ret = false;768			goto clean;769		}770 771		if (of_property_read_u32_index(c_node, "regulator-coupled-max-spread",772					       index, &c_max_spread)) {773			ret = false;774			goto clean;775		}776 777		if (c_max_spread != max_spread) {778			dev_err(&rdev->dev,779				"coupled regulators max_spread mismatch\n");780			ret = false;781			goto clean;782		}783 784clean:785		of_node_put(c_node);786		if (!ret)787			break;788	}789 790	return ret;791}792 793/**794 * of_parse_coupled_regulator() - Get regulator_dev pointer from rdev's property795 * @rdev: Pointer to regulator_dev, whose DTS is used as a source to parse796 *	  "regulator-coupled-with" property797 * @index: Index in phandles array798 *799 * Return: Pointer to the &struct regulator_dev parsed from DTS, or %NULL if800 *	   it has not yet been registered.801 */802struct regulator_dev *of_parse_coupled_regulator(struct regulator_dev *rdev,803						 int index)804{805	struct device_node *node = rdev->dev.of_node;806	struct device_node *c_node;807	struct regulator_dev *c_rdev;808 809	c_node = of_parse_phandle(node, "regulator-coupled-with", index);810	if (!c_node)811		return NULL;812 813	c_rdev = of_find_regulator_by_node(c_node);814 815	of_node_put(c_node);816 817	return c_rdev;818}819 820/*821 * Check if name is a supply name according to the '*-supply' pattern822 * return 0 if false823 * return length of supply name without the -supply824 */825static int is_supply_name(const char *name)826{827	int strs, i;828 829	strs = strlen(name);830	/* string need to be at minimum len(x-supply) */831	if (strs < 8)832		return 0;833	for (i = strs - 6; i > 0; i--) {834		/* find first '-' and check if right part is supply */835		if (name[i] != '-')836			continue;837		if (strcmp(name + i + 1, "supply") != 0)838			return 0;839		return i;840	}841	return 0;842}843 844/**845 * of_regulator_bulk_get_all - get multiple regulator consumers846 *847 * @dev:	Device to supply848 * @np:		device node to search for consumers849 * @consumers:  Configuration of consumers; clients are stored here.850 *851 * This helper function allows drivers to get several regulator852 * consumers in one operation.  If any of the regulators cannot be853 * acquired then any regulators that were allocated will be freed854 * before returning to the caller, and @consumers will not be855 * changed.856 *857 * Return: Number of regulators on success, or a negative error number858 *	   on failure.859 */860int of_regulator_bulk_get_all(struct device *dev, struct device_node *np,861			      struct regulator_bulk_data **consumers)862{863	int num_consumers = 0;864	struct regulator *tmp;865	struct regulator_bulk_data *_consumers = NULL;866	struct property *prop;867	int i, n = 0, ret;868	char name[64];869 870	/*871	 * first pass: get numbers of xxx-supply872	 * second pass: fill consumers873	 */874restart:875	for_each_property_of_node(np, prop) {876		i = is_supply_name(prop->name);877		if (i == 0)878			continue;879		if (!_consumers) {880			num_consumers++;881			continue;882		} else {883			memcpy(name, prop->name, i);884			name[i] = '\0';885			tmp = regulator_get(dev, name);886			if (IS_ERR(tmp)) {887				ret = PTR_ERR(tmp);888				goto error;889			}890			_consumers[n].consumer = tmp;891			n++;892			continue;893		}894	}895	if (_consumers) {896		*consumers = _consumers;897		return num_consumers;898	}899	if (num_consumers == 0)900		return 0;901	_consumers = kmalloc_array(num_consumers,902				   sizeof(struct regulator_bulk_data),903				   GFP_KERNEL);904	if (!_consumers)905		return -ENOMEM;906	goto restart;907 908error:909	while (--n >= 0)910		regulator_put(_consumers[n].consumer);911	kfree(_consumers);912	return ret;913}914EXPORT_SYMBOL_GPL(of_regulator_bulk_get_all);915