diff options
Diffstat (limited to 'drivers/regulator/of_regulator.c')
| -rw-r--r-- | drivers/regulator/of_regulator.c | 191 |
1 files changed, 191 insertions, 0 deletions
diff --git a/drivers/regulator/of_regulator.c b/drivers/regulator/of_regulator.c new file mode 100644 index 00000000000..ee5e67bc8d5 --- /dev/null +++ b/drivers/regulator/of_regulator.c @@ -0,0 +1,191 @@ +/* + * OF helpers for regulator framework + * + * Copyright (C) 2011 Texas Instruments, Inc. + * Rajendra Nayak <rnayak@ti.com> + * + * 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; + else + 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; +} +EXPORT_SYMBOL_GPL(of_get_regulator_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_node_put(devm_matches->matches[i].of_node); +} + +/** + * 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), + GFP_KERNEL); + 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) + continue; + + if (strcmp(match->name, name)) + continue; + + match->init_data = + of_get_regulator_init_data(dev, child); + if (!match->init_data) { + dev_err(dev, + "failed to parse DT for regulator %s\n", + child->name); + return -EINVAL; + } + match->of_node = of_node_get(child); + count++; + break; + } + } + + return count; +} +EXPORT_SYMBOL_GPL(of_regulator_match); |