blob: ee5e67bc8d5bed53b6c1577bd20071f46542da2f [file] [log] [blame]
* OF helpers for regulator framework
* Copyright (C) 2011 Texas Instruments, Inc.
* Rajendra Nayak <>
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/of.h>
#include <linux/regulator/machine.h>
#include <linux/regulator/of_regulator.h>
static void of_get_regulation_constraints(struct device_node *np,
struct regulator_init_data **init_data)
const __be32 *min_uV, *max_uV;
struct regulation_constraints *constraints = &(*init_data)->constraints;
int ret;
u32 pval;
constraints->name = of_get_property(np, "regulator-name", NULL);
min_uV = of_get_property(np, "regulator-min-microvolt", NULL);
if (min_uV)
constraints->min_uV = be32_to_cpu(*min_uV);
max_uV = of_get_property(np, "regulator-max-microvolt", NULL);
if (max_uV)
constraints->max_uV = be32_to_cpu(*max_uV);
/* Voltage change possible? */
if (constraints->min_uV != constraints->max_uV)
constraints->valid_ops_mask |= REGULATOR_CHANGE_VOLTAGE;
/* Only one voltage? Then make sure it's set. */
if (min_uV && max_uV && constraints->min_uV == constraints->max_uV)
constraints->apply_uV = true;
if (!of_property_read_u32(np, "regulator-microvolt-offset", &pval))
constraints->uV_offset = pval;
if (!of_property_read_u32(np, "regulator-min-microamp", &pval))
constraints->min_uA = pval;
if (!of_property_read_u32(np, "regulator-max-microamp", &pval))
constraints->max_uA = pval;
/* Current change possible? */
if (constraints->min_uA != constraints->max_uA)
constraints->valid_ops_mask |= REGULATOR_CHANGE_CURRENT;
constraints->boot_on = of_property_read_bool(np, "regulator-boot-on");
constraints->always_on = of_property_read_bool(np, "regulator-always-on");
if (!constraints->always_on) /* status change should be possible. */
constraints->valid_ops_mask |= REGULATOR_CHANGE_STATUS;
if (of_property_read_bool(np, "regulator-allow-bypass"))
constraints->valid_ops_mask |= REGULATOR_CHANGE_BYPASS;
ret = of_property_read_u32(np, "regulator-ramp-delay", &pval);
if (!ret) {
if (pval)
constraints->ramp_delay = pval;
constraints->ramp_disable = true;
ret = of_property_read_u32(np, "regulator-enable-ramp-delay", &pval);
if (!ret)
constraints->enable_time = pval;
* of_get_regulator_init_data - extract regulator_init_data structure info
* @dev: device requesting for regulator_init_data
* Populates regulator_init_data structure by extracting data from device
* tree node, returns a pointer to the populated struture or NULL if memory
* alloc fails.
struct regulator_init_data *of_get_regulator_init_data(struct device *dev,
struct device_node *node)
struct regulator_init_data *init_data;
if (!node)
return NULL;
init_data = devm_kzalloc(dev, sizeof(*init_data), GFP_KERNEL);
if (!init_data)
return NULL; /* Out of memory? */
of_get_regulation_constraints(node, &init_data);
return init_data;
struct devm_of_regulator_matches {
struct of_regulator_match *matches;
unsigned int num_matches;
static void devm_of_regulator_put_matches(struct device *dev, void *res)
struct devm_of_regulator_matches *devm_matches = res;
int i;
for (i = 0; i < devm_matches->num_matches; i++)
* of_regulator_match - extract multiple regulator init data from device tree.
* @dev: device requesting the data
* @node: parent device node of the regulators
* @matches: match table for the regulators
* @num_matches: number of entries in match table
* This function uses a match table specified by the regulator driver to
* parse regulator init data from the device tree. @node is expected to
* contain a set of child nodes, each providing the init data for one
* regulator. The data parsed from a child node will be matched to a regulator
* based on either the deprecated property regulator-compatible if present,
* or otherwise the child node's name. Note that the match table is modified
* in place and an additional of_node reference is taken for each matched
* regulator.
* Returns the number of matches found or a negative error code on failure.
int of_regulator_match(struct device *dev, struct device_node *node,
struct of_regulator_match *matches,
unsigned int num_matches)
unsigned int count = 0;
unsigned int i;
const char *name;
struct device_node *child;
struct devm_of_regulator_matches *devm_matches;
if (!dev || !node)
return -EINVAL;
devm_matches = devres_alloc(devm_of_regulator_put_matches,
sizeof(struct devm_of_regulator_matches),
if (!devm_matches)
return -ENOMEM;
devm_matches->matches = matches;
devm_matches->num_matches = num_matches;
devres_add(dev, devm_matches);
for (i = 0; i < num_matches; i++) {
struct of_regulator_match *match = &matches[i];
match->init_data = NULL;
match->of_node = NULL;
for_each_child_of_node(node, child) {
name = of_get_property(child,
"regulator-compatible", NULL);
if (!name)
name = child->name;
for (i = 0; i < num_matches; i++) {
struct of_regulator_match *match = &matches[i];
if (match->of_node)
if (strcmp(match->name, name))
match->init_data =
of_get_regulator_init_data(dev, child);
if (!match->init_data) {
"failed to parse DT for regulator %s\n",
return -EINVAL;
match->of_node = of_node_get(child);
return count;