base.c

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/*
 * Procedures for creating, accessing and interpreting the device tree.
 *
 * Paul Mackerras   August 1996.
 * Copyright (C) 1996-2005 Paul Mackerras.
 *
 *  Adapted for 64bit PowerPC by Dave Engebretsen and Peter Bergner.
 *    {engebret|bergner}@us.ibm.com
 *
 *  Adapted for sparc and sparc64 by David S. Miller [email protected]
 *
 *  Reconsolidated from arch/x/kernel/prom.c by Stephen Rothwell and
 *  Grant Likely.
 *
 *      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/ctype.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/spinlock.h>
#include <linux/slab.h>
#include <linux/proc_fs.h>

struct alias_prop {
    struct list_head link;
    const char *alias;
    struct device_node *np;
    int id;
    char stem[0];
};

static LIST_HEAD(aliases_lookup);

struct device_node *allnodes;
struct device_node *of_chosen;
struct device_node *of_aliases;

static DEFINE_MUTEX(of_aliases_mutex);

/* use when traversing tree through the allnext, child, sibling,
 * or parent members of struct device_node.
 */
DEFINE_RWLOCK(devtree_lock);

int of_n_addr_cells(struct device_node *np)
{
    const __be32 *ip;

    do {
        if (np->parent)
            np = np->parent;
        ip = of_get_property(np, "#address-cells", NULL);
        if (ip)
            return be32_to_cpup(ip);
    } while (np->parent);
    /* No #address-cells property for the root node */
    return OF_ROOT_NODE_ADDR_CELLS_DEFAULT;
}
EXPORT_SYMBOL(of_n_addr_cells);

int of_n_size_cells(struct device_node *np)
{
    const __be32 *ip;

    do {
        if (np->parent)
            np = np->parent;
        ip = of_get_property(np, "#size-cells", NULL);
        if (ip)
            return be32_to_cpup(ip);
    } while (np->parent);
    /* No #size-cells property for the root node */
    return OF_ROOT_NODE_SIZE_CELLS_DEFAULT;
}
EXPORT_SYMBOL(of_n_size_cells);

#if defined(CONFIG_OF_DYNAMIC)

struct device_node *of_node_get(struct device_node *node)
{
    if (node)
        kref_get(&node->kref);
    return node;
}
EXPORT_SYMBOL(of_node_get);

static inline struct device_node *kref_to_device_node(struct kref *kref)
{
    return container_of(kref, struct device_node, kref);
}

static void of_node_release(struct kref *kref)
{
    struct device_node *node = kref_to_device_node(kref);
    struct property *prop = node->properties;

    /* We should never be releasing nodes that haven't been detached. */
    if (!of_node_check_flag(node, OF_DETACHED)) {
        pr_err("ERROR: Bad of_node_put() on %s\n", node->full_name);
        dump_stack();
        kref_init(&node->kref);
        return;
    }

    if (!of_node_check_flag(node, OF_DYNAMIC))
        return;

    while (prop) {
        struct property *next = prop->next;
        kfree(prop->name);
        kfree(prop->value);
        kfree(prop);
        prop = next;

        if (!prop) {
            prop = node->deadprops;
            node->deadprops = NULL;
        }
    }
    kfree(node->full_name);
    kfree(node->data);
    kfree(node);
}

void of_node_put(struct device_node *node)
{
    if (node)
        kref_put(&node->kref, of_node_release);
}
EXPORT_SYMBOL(of_node_put);
#endif /* CONFIG_OF_DYNAMIC */

struct property *of_find_property(const struct device_node *np,
                  const char *name,
                  int *lenp)
{
    struct property *pp;

    if (!np)
        return NULL;

    read_lock(&devtree_lock);
    for (pp = np->properties; pp; pp = pp->next) {
        if (of_prop_cmp(pp->name, name) == 0) {
            if (lenp)
                *lenp = pp->length;
            break;
        }
    }
    read_unlock(&devtree_lock);

    return pp;
}
EXPORT_SYMBOL(of_find_property);

struct device_node *of_find_all_nodes(struct device_node *prev)
{
    struct device_node *np;

    read_lock(&devtree_lock);
    np = prev ? prev->allnext : allnodes;
    for (; np != NULL; np = np->allnext)
        if (of_node_get(np))
            break;
    of_node_put(prev);
    read_unlock(&devtree_lock);
    return np;
}
EXPORT_SYMBOL(of_find_all_nodes);

/*
 * Find a property with a given name for a given node
 * and return the value.
 */
const void *of_get_property(const struct device_node *np, const char *name,
             int *lenp)
{
    struct property *pp = of_find_property(np, name, lenp);

    return pp ? pp->value : NULL;
}
EXPORT_SYMBOL(of_get_property);

int of_device_is_compatible(const struct device_node *device,
        const char *compat)
{
    const char* cp;
    int cplen, l;

    cp = of_get_property(device, "compatible", &cplen);
    if (cp == NULL)
        return 0;
    while (cplen > 0) {
        if (of_compat_cmp(cp, compat, strlen(compat)) == 0)
            return 1;
        l = strlen(cp) + 1;
        cp += l;
        cplen -= l;
    }

    return 0;
}
EXPORT_SYMBOL(of_device_is_compatible);

int of_machine_is_compatible(const char *compat)
{
    struct device_node *root;
    int rc = 0;

    root = of_find_node_by_path("/");
    if (root) {
        rc = of_device_is_compatible(root, compat);
        of_node_put(root);
    }
    return rc;
}
EXPORT_SYMBOL(of_machine_is_compatible);

int of_device_is_available(const struct device_node *device)
{
    const char *status;
    int statlen;

    status = of_get_property(device, "status", &statlen);
    if (status == NULL)
        return 1;

    if (statlen > 0) {
        if (!strcmp(status, "okay") || !strcmp(status, "ok"))
            return 1;
    }

    return 0;
}
EXPORT_SYMBOL(of_device_is_available);

struct device_node *of_get_parent(const struct device_node *node)
{
    struct device_node *np;

    if (!node)
        return NULL;

    read_lock(&devtree_lock);
    np = of_node_get(node->parent);
    read_unlock(&devtree_lock);
    return np;
}
EXPORT_SYMBOL(of_get_parent);

struct device_node *of_get_next_parent(struct device_node *node)
{
    struct device_node *parent;

    if (!node)
        return NULL;

    read_lock(&devtree_lock);
    parent = of_node_get(node->parent);
    of_node_put(node);
    read_unlock(&devtree_lock);
    return parent;
}

struct device_node *of_get_next_child(const struct device_node *node,
    struct device_node *prev)
{
    struct device_node *next;

    read_lock(&devtree_lock);
    next = prev ? prev->sibling : node->child;
    for (; next; next = next->sibling)
        if (of_node_get(next))
            break;
    of_node_put(prev);
    read_unlock(&devtree_lock);
    return next;
}
EXPORT_SYMBOL(of_get_next_child);

struct device_node *of_get_next_available_child(const struct device_node *node,
    struct device_node *prev)
{
    struct device_node *next;

    read_lock(&devtree_lock);
    next = prev ? prev->sibling : node->child;
    for (; next; next = next->sibling) {
        if (!of_device_is_available(next))
            continue;
        if (of_node_get(next))
            break;
    }
    of_node_put(prev);
    read_unlock(&devtree_lock);
    return next;
}
EXPORT_SYMBOL(of_get_next_available_child);

struct device_node *of_get_child_by_name(const struct device_node *node,
                const char *name)
{
    struct device_node *child;

    for_each_child_of_node(node, child)
        if (child->name && (of_node_cmp(child->name, name) == 0))
            break;
    return child;
}
EXPORT_SYMBOL(of_get_child_by_name);

struct device_node *of_find_node_by_path(const char *path)
{
    struct device_node *np = allnodes;

    read_lock(&devtree_lock);
    for (; np; np = np->allnext) {
        if (np->full_name && (of_node_cmp(np->full_name, path) == 0)
            && of_node_get(np))
            break;
    }
    read_unlock(&devtree_lock);
    return np;
}
EXPORT_SYMBOL(of_find_node_by_path);

struct device_node *of_find_node_by_name(struct device_node *from,
    const char *name)
{
    struct device_node *np;

    read_lock(&devtree_lock);
    np = from ? from->allnext : allnodes;
    for (; np; np = np->allnext)
        if (np->name && (of_node_cmp(np->name, name) == 0)
            && of_node_get(np))
            break;
    of_node_put(from);
    read_unlock(&devtree_lock);
    return np;
}
EXPORT_SYMBOL(of_find_node_by_name);

struct device_node *of_find_node_by_type(struct device_node *from,
    const char *type)
{
    struct device_node *np;

    read_lock(&devtree_lock);
    np = from ? from->allnext : allnodes;
    for (; np; np = np->allnext)
        if (np->type && (of_node_cmp(np->type, type) == 0)
            && of_node_get(np))
            break;
    of_node_put(from);
    read_unlock(&devtree_lock);
    return np;
}
EXPORT_SYMBOL(of_find_node_by_type);

struct device_node *of_find_compatible_node(struct device_node *from,
    const char *type, const char *compatible)
{
    struct device_node *np;

    read_lock(&devtree_lock);
    np = from ? from->allnext : allnodes;
    for (; np; np = np->allnext) {
        if (type
            && !(np->type && (of_node_cmp(np->type, type) == 0)))
            continue;
        if (of_device_is_compatible(np, compatible) && of_node_get(np))
            break;
    }
    of_node_put(from);
    read_unlock(&devtree_lock);
    return np;
}
EXPORT_SYMBOL(of_find_compatible_node);

struct device_node *of_find_node_with_property(struct device_node *from,
    const char *prop_name)
{
    struct device_node *np;
    struct property *pp;

    read_lock(&devtree_lock);
    np = from ? from->allnext : allnodes;
    for (; np; np = np->allnext) {
        for (pp = np->properties; pp; pp = pp->next) {
            if (of_prop_cmp(pp->name, prop_name) == 0) {
                of_node_get(np);
                goto out;
            }
        }
    }
out:
    of_node_put(from);
    read_unlock(&devtree_lock);
    return np;
}
EXPORT_SYMBOL(of_find_node_with_property);

const struct of_device_id *of_match_node(const struct of_device_id *matches,
                     const struct device_node *node)
{
    if (!matches)
        return NULL;

    while (matches->name[0] || matches->type[0] || matches->compatible[0]) {
        int match = 1;
        if (matches->name[0])
            match &= node->name
                && !strcmp(matches->name, node->name);
        if (matches->type[0])
            match &= node->type
                && !strcmp(matches->type, node->type);
        if (matches->compatible[0])
            match &= of_device_is_compatible(node,
                        matches->compatible);
        if (match)
            return matches;
        matches++;
    }
    return NULL;
}
EXPORT_SYMBOL(of_match_node);

struct device_node *of_find_matching_node(struct device_node *from,
                      const struct of_device_id *matches)
{
    struct device_node *np;

    read_lock(&devtree_lock);
    np = from ? from->allnext : allnodes;
    for (; np; np = np->allnext) {
        if (of_match_node(matches, np) && of_node_get(np))
            break;
    }
    of_node_put(from);
    read_unlock(&devtree_lock);
    return np;
}
EXPORT_SYMBOL(of_find_matching_node);

int of_modalias_node(struct device_node *node, char *modalias, int len)
{
    const char *compatible, *p;
    int cplen;

    compatible = of_get_property(node, "compatible", &cplen);
    if (!compatible || strlen(compatible) > cplen)
        return -ENODEV;
    p = strchr(compatible, ',');
    strlcpy(modalias, p ? p + 1 : compatible, len);
    return 0;
}
EXPORT_SYMBOL_GPL(of_modalias_node);

struct device_node *of_find_node_by_phandle(phandle handle)
{
    struct device_node *np;

    read_lock(&devtree_lock);
    for (np = allnodes; np; np = np->allnext)
        if (np->phandle == handle)
            break;
    of_node_get(np);
    read_unlock(&devtree_lock);
    return np;
}
EXPORT_SYMBOL(of_find_node_by_phandle);

int of_property_read_u32_array(const struct device_node *np,
                   const char *propname, u32 *out_values,
                   size_t sz)
{
    struct property *prop = of_find_property(np, propname, NULL);
    const __be32 *val;

    if (!prop)
        return -EINVAL;
    if (!prop->value)
        return -ENODATA;
    if ((sz * sizeof(*out_values)) > prop->length)
        return -EOVERFLOW;

    val = prop->value;
    while (sz--)
        *out_values++ = be32_to_cpup(val++);
    return 0;
}
EXPORT_SYMBOL_GPL(of_property_read_u32_array);

int of_property_read_u64(const struct device_node *np, const char *propname,
             u64 *out_value)
{
    struct property *prop = of_find_property(np, propname, NULL);

    if (!prop)
        return -EINVAL;
    if (!prop->value)
        return -ENODATA;
    if (sizeof(*out_value) > prop->length)
        return -EOVERFLOW;
    *out_value = of_read_number(prop->value, 2);
    return 0;
}
EXPORT_SYMBOL_GPL(of_property_read_u64);

int of_property_read_string(struct device_node *np, const char *propname,
                const char **out_string)
{
    struct property *prop = of_find_property(np, propname, NULL);
    if (!prop)
        return -EINVAL;
    if (!prop->value)
        return -ENODATA;
    if (strnlen(prop->value, prop->length) >= prop->length)
        return -EILSEQ;
    *out_string = prop->value;
    return 0;
}
EXPORT_SYMBOL_GPL(of_property_read_string);

int of_property_read_string_index(struct device_node *np, const char *propname,
                  int index, const char **output)
{
    struct property *prop = of_find_property(np, propname, NULL);
    int i = 0;
    size_t l = 0, total = 0;
    const char *p;

    if (!prop)
        return -EINVAL;
    if (!prop->value)
        return -ENODATA;
    if (strnlen(prop->value, prop->length) >= prop->length)
        return -EILSEQ;

    p = prop->value;

    for (i = 0; total < prop->length; total += l, p += l) {
        l = strlen(p) + 1;
        if (i++ == index) {
            *output = p;
            return 0;
        }
    }
    return -ENODATA;
}
EXPORT_SYMBOL_GPL(of_property_read_string_index);

int of_property_match_string(struct device_node *np, const char *propname,
                 const char *string)
{
    struct property *prop = of_find_property(np, propname, NULL);
    size_t l;
    int i;
    const char *p, *end;

    if (!prop)
        return -EINVAL;
    if (!prop->value)
        return -ENODATA;

    p = prop->value;
    end = p + prop->length;

    for (i = 0; p < end; i++, p += l) {
        l = strlen(p) + 1;
        if (p + l > end)
            return -EILSEQ;
        pr_debug("comparing %s with %s\n", string, p);
        if (strcmp(string, p) == 0)
            return i; /* Found it; return index */
    }
    return -ENODATA;
}
EXPORT_SYMBOL_GPL(of_property_match_string);

int of_property_count_strings(struct device_node *np, const char *propname)
{
    struct property *prop = of_find_property(np, propname, NULL);
    int i = 0;
    size_t l = 0, total = 0;
    const char *p;

    if (!prop)
        return -EINVAL;
    if (!prop->value)
        return -ENODATA;
    if (strnlen(prop->value, prop->length) >= prop->length)
        return -EILSEQ;

    p = prop->value;

    for (i = 0; total < prop->length; total += l, p += l, i++)
        l = strlen(p) + 1;

    return i;
}
EXPORT_SYMBOL_GPL(of_property_count_strings);

struct device_node *
of_parse_phandle(struct device_node *np, const char *phandle_name, int index)
{
    const __be32 *phandle;
    int size;

    phandle = of_get_property(np, phandle_name, &size);
    if ((!phandle) || (size < sizeof(*phandle) * (index + 1)))
        return NULL;

    return of_find_node_by_phandle(be32_to_cpup(phandle + index));
}
EXPORT_SYMBOL(of_parse_phandle);

int of_parse_phandle_with_args(struct device_node *np, const char *list_name,
                const char *cells_name, int index,
                struct of_phandle_args *out_args)
{
    const __be32 *list, *list_end;
    int size, cur_index = 0;
    uint32_t count = 0;
    struct device_node *node = NULL;
    phandle phandle;

    /* Retrieve the phandle list property */
    list = of_get_property(np, list_name, &size);
    if (!list)
        return -ENOENT;
    list_end = list + size / sizeof(*list);

    /* Loop over the phandles until all the requested entry is found */
    while (list < list_end) {
        count = 0;

        /*
         * If phandle is 0, then it is an empty entry with no
         * arguments.  Skip forward to the next entry.
         */
        phandle = be32_to_cpup(list++);
        if (phandle) {
            /*
             * Find the provider node and parse the #*-cells
             * property to determine the argument length
             */
            node = of_find_node_by_phandle(phandle);
            if (!node) {
                pr_err("%s: could not find phandle\n",
                     np->full_name);
                break;
            }
            if (of_property_read_u32(node, cells_name, &count)) {
                pr_err("%s: could not get %s for %s\n",
                     np->full_name, cells_name,
                     node->full_name);
                break;
            }

            /*
             * Make sure that the arguments actually fit in the
             * remaining property data length
             */
            if (list + count > list_end) {
                pr_err("%s: arguments longer than property\n",
                     np->full_name);
                break;
            }
        }

        /*
         * All of the error cases above bail out of the loop, so at
         * this point, the parsing is successful. If the requested
         * index matches, then fill the out_args structure and return,
         * or return -ENOENT for an empty entry.
         */
        if (cur_index == index) {
            if (!phandle)
                return -ENOENT;

            if (out_args) {
                int i;
                if (WARN_ON(count > MAX_PHANDLE_ARGS))
                    count = MAX_PHANDLE_ARGS;
                out_args->np = node;
                out_args->args_count = count;
                for (i = 0; i < count; i++)
                    out_args->args[i] = be32_to_cpup(list++);
            }
            return 0;
        }

        of_node_put(node);
        node = NULL;
        list += count;
        cur_index++;
    }

    /* Loop exited without finding a valid entry; return an error */
    if (node)
        of_node_put(node);
    return -EINVAL;
}
EXPORT_SYMBOL(of_parse_phandle_with_args);

int prom_add_property(struct device_node *np, struct property *prop)
{
    struct property **next;
    unsigned long flags;

    prop->next = NULL;
    write_lock_irqsave(&devtree_lock, flags);
    next = &np->properties;
    while (*next) {
        if (strcmp(prop->name, (*next)->name) == 0) {
            /* duplicate ! don't insert it */
            write_unlock_irqrestore(&devtree_lock, flags);
            return -1;
        }
        next = &(*next)->next;
    }
    *next = prop;
    write_unlock_irqrestore(&devtree_lock, flags);

#ifdef CONFIG_PROC_DEVICETREE
    /* try to add to proc as well if it was initialized */
    if (np->pde)
        proc_device_tree_add_prop(np->pde, prop);
#endif /* CONFIG_PROC_DEVICETREE */

    return 0;
}

int prom_remove_property(struct device_node *np, struct property *prop)
{
    struct property **next;
    unsigned long flags;
    int found = 0;

    write_lock_irqsave(&devtree_lock, flags);
    next = &np->properties;
    while (*next) {
        if (*next == prop) {
            /* found the node */
            *next = prop->next;
            prop->next = np->deadprops;
            np->deadprops = prop;
            found = 1;
            break;
        }
        next = &(*next)->next;
    }
    write_unlock_irqrestore(&devtree_lock, flags);

    if (!found)
        return -ENODEV;

#ifdef CONFIG_PROC_DEVICETREE
    /* try to remove the proc node as well */
    if (np->pde)
        proc_device_tree_remove_prop(np->pde, prop);
#endif /* CONFIG_PROC_DEVICETREE */

    return 0;
}

/*
 * prom_update_property - Update a property in a node, if the property does
 * not exist, add it.
 *
 * Note that we don't actually remove it, since we have given out
 * who-knows-how-many pointers to the data using get-property.
 * Instead we just move the property to the "dead properties" list,
 * and add the new property to the property list
 */
int prom_update_property(struct device_node *np,
             struct property *newprop)
{
    struct property **next, *oldprop;
    unsigned long flags;
    int found = 0;

    if (!newprop->name)
        return -EINVAL;

    oldprop = of_find_property(np, newprop->name, NULL);
    if (!oldprop)
        return prom_add_property(np, newprop);

    write_lock_irqsave(&devtree_lock, flags);
    next = &np->properties;
    while (*next) {
        if (*next == oldprop) {
            /* found the node */
            newprop->next = oldprop->next;
            *next = newprop;
            oldprop->next = np->deadprops;
            np->deadprops = oldprop;
            found = 1;
            break;
        }
        next = &(*next)->next;
    }
    write_unlock_irqrestore(&devtree_lock, flags);

    if (!found)
        return -ENODEV;

#ifdef CONFIG_PROC_DEVICETREE
    /* try to add to proc as well if it was initialized */
    if (np->pde)
        proc_device_tree_update_prop(np->pde, newprop, oldprop);
#endif /* CONFIG_PROC_DEVICETREE */

    return 0;
}

#if defined(CONFIG_OF_DYNAMIC)
/*
 * Support for dynamic device trees.
 *
 * On some platforms, the device tree can be manipulated at runtime.
 * The routines in this section support adding, removing and changing
 * device tree nodes.
 */

void of_attach_node(struct device_node *np)
{
    unsigned long flags;

    write_lock_irqsave(&devtree_lock, flags);
    np->sibling = np->parent->child;
    np->allnext = allnodes;
    np->parent->child = np;
    allnodes = np;
    write_unlock_irqrestore(&devtree_lock, flags);
}

void of_detach_node(struct device_node *np)
{
    struct device_node *parent;
    unsigned long flags;

    write_lock_irqsave(&devtree_lock, flags);

    parent = np->parent;
    if (!parent)
        goto out_unlock;

    if (allnodes == np)
        allnodes = np->allnext;
    else {
        struct device_node *prev;
        for (prev = allnodes;
             prev->allnext != np;
             prev = prev->allnext)
            ;
        prev->allnext = np->allnext;
    }

    if (parent->child == np)
        parent->child = np->sibling;
    else {
        struct device_node *prevsib;
        for (prevsib = np->parent->child;
             prevsib->sibling != np;
             prevsib = prevsib->sibling)
            ;
        prevsib->sibling = np->sibling;
    }

    of_node_set_flag(np, OF_DETACHED);

out_unlock:
    write_unlock_irqrestore(&devtree_lock, flags);
}
#endif /* defined(CONFIG_OF_DYNAMIC) */

static void of_alias_add(struct alias_prop *ap, struct device_node *np,
             int id, const char *stem, int stem_len)
{
    ap->np = np;
    ap->id = id;
    strncpy(ap->stem, stem, stem_len);
    ap->stem[stem_len] = 0;
    list_add_tail(&ap->link, &aliases_lookup);
    pr_debug("adding DT alias:%s: stem=%s id=%i node=%s\n",
         ap->alias, ap->stem, ap->id, of_node_full_name(np));
}

void of_alias_scan(void * (*dt_alloc)(u64 size, u64 align))
{
    struct property *pp;

    of_chosen = of_find_node_by_path("/chosen");
    if (of_chosen == NULL)
        of_chosen = of_find_node_by_path("/chosen@0");
    of_aliases = of_find_node_by_path("/aliases");
    if (!of_aliases)
        return;

    for_each_property_of_node(of_aliases, pp) {
        const char *start = pp->name;
        const char *end = start + strlen(start);
        struct device_node *np;
        struct alias_prop *ap;
        int id, len;

        /* Skip those we do not want to proceed */
        if (!strcmp(pp->name, "name") ||
            !strcmp(pp->name, "phandle") ||
            !strcmp(pp->name, "linux,phandle"))
            continue;

        np = of_find_node_by_path(pp->value);
        if (!np)
            continue;

        /* walk the alias backwards to extract the id and work out
         * the 'stem' string */
        while (isdigit(*(end-1)) && end > start)
            end--;
        len = end - start;

        if (kstrtoint(end, 10, &id) < 0)
            continue;

        /* Allocate an alias_prop with enough space for the stem */
        ap = dt_alloc(sizeof(*ap) + len + 1, 4);
        if (!ap)
            continue;
        ap->alias = start;
        of_alias_add(ap, np, id, start, len);
    }
}

int of_alias_get_id(struct device_node *np, const char *stem)
{
    struct alias_prop *app;
    int id = -ENODEV;

    mutex_lock(&of_aliases_mutex);
    list_for_each_entry(app, &aliases_lookup, link) {
        if (strcmp(app->stem, stem) != 0)
            continue;

        if (np == app->np) {
            id = app->id;
            break;
        }
    }
    mutex_unlock(&of_aliases_mutex);

    return id;
}
EXPORT_SYMBOL_GPL(of_alias_get_id);

const __be32 *of_prop_next_u32(struct property *prop, const __be32 *cur,
                   u32 *pu)
{
    const void *curv = cur;

    if (!prop)
        return NULL;

    if (!cur) {
        curv = prop->value;
        goto out_val;
    }

    curv += sizeof(*cur);
    if (curv >= prop->value + prop->length)
        return NULL;

out_val:
    *pu = be32_to_cpup(curv);
    return curv;
}
EXPORT_SYMBOL_GPL(of_prop_next_u32);

const char *of_prop_next_string(struct property *prop, const char *cur)
{
    const void *curv = cur;

    if (!prop)
        return NULL;

    if (!cur)
        return prop->value;

    curv += strlen(cur) + 1;
    if (curv >= prop->value + prop->length)
        return NULL;

    return curv;
}
EXPORT_SYMBOL_GPL(of_prop_next_string);