of_regulator.c

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/*
 * OF helpers for regulator framework
 *
 * Copyright (C) 2011 Texas Instruments, Inc.
 * Rajendra Nayak <[email protected]>
 *
 * 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, *uV_offset;
    const __be32 *min_uA, *max_uA, *ramp_delay;
    struct regulation_constraints *constraints = &(*init_data)->constraints;

    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;

    uV_offset = of_get_property(np, "regulator-microvolt-offset", NULL);
    if (uV_offset)
        constraints->uV_offset = be32_to_cpu(*uV_offset);
    min_uA = of_get_property(np, "regulator-min-microamp", NULL);
    if (min_uA)
        constraints->min_uA = be32_to_cpu(*min_uA);
    max_uA = of_get_property(np, "regulator-max-microamp", NULL);
    if (max_uA)
        constraints->max_uA = be32_to_cpu(*max_uA);

    /* Current change possible? */
    if (constraints->min_uA != constraints->max_uA)
        constraints->valid_ops_mask |= REGULATOR_CHANGE_CURRENT;

    if (of_find_property(np, "regulator-boot-on", NULL))
        constraints->boot_on = true;

    if (of_find_property(np, "regulator-always-on", NULL))
        constraints->always_on = true;
    else /* status change should be possible if not always on. */
        constraints->valid_ops_mask |= REGULATOR_CHANGE_STATUS;

    ramp_delay = of_get_property(np, "regulator-ramp-delay", NULL);
    if (ramp_delay)
        constraints->ramp_delay = be32_to_cpu(*ramp_delay);
}

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);

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;

    if (!dev || !node)
        return -EINVAL;

    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 = child;
            count++;
            break;
        }
    }

    return count;
}
EXPORT_SYMBOL_GPL(of_regulator_match);