*
* Adapted for sparc and sparc64 by David S. Miller davem@davemloft.net
*
- * Reconsolidated from arch/x/kernel/prom.c by Stephen Rothwell.
+ * 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
#include <linux/module.h>
#include <linux/of.h>
#include <linux/spinlock.h>
+#include <linux/slab.h>
+#include <linux/proc_fs.h>
+
+struct device_node *allnodes;
+struct device_node *of_chosen;
/* use when traversing tree through the allnext, child, sibling,
* or parent members of struct device_node.
np = np->parent;
ip = of_get_property(np, "#address-cells", NULL);
if (ip)
- return *ip;
+ return be32_to_cpup(ip);
} while (np->parent);
/* No #address-cells property for the root node */
return OF_ROOT_NODE_ADDR_CELLS_DEFAULT;
np = np->parent;
ip = of_get_property(np, "#size-cells", NULL);
if (ip)
- return *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_SPARC) /* SPARC doesn't do ref counting (yet) */
+/**
+ * of_node_get - Increment refcount of a node
+ * @node: Node to inc refcount, NULL is supported to
+ * simplify writing of callers
+ *
+ * Returns node.
+ */
+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);
+}
+
+/**
+ * of_node_release - release a dynamically allocated node
+ * @kref: kref element of the node to be released
+ *
+ * In of_node_put() this function is passed to kref_put()
+ * as the destructor.
+ */
+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);
+}
+
+/**
+ * of_node_put - Decrement refcount of a node
+ * @node: Node to dec refcount, NULL is supported to
+ * simplify writing of callers
+ *
+ */
+void of_node_put(struct device_node *node)
+{
+ if (node)
+ kref_put(&node->kref, of_node_release);
+}
+EXPORT_SYMBOL(of_node_put);
+#endif /* !CONFIG_SPARC */
+
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 != 0; pp = pp->next) {
if (of_prop_cmp(pp->name, name) == 0) {
}
EXPORT_SYMBOL(of_find_property);
+/**
+ * of_find_all_nodes - Get next node in global list
+ * @prev: Previous node or NULL to start iteration
+ * of_node_put() will be called on it
+ *
+ * Returns a node pointer with refcount incremented, use
+ * of_node_put() on it when done.
+ */
+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.
return 0;
}
EXPORT_SYMBOL(of_device_is_compatible);
+
+/**
+ * of_machine_is_compatible - Test root of device tree for a given compatible value
+ * @compat: compatible string to look for in root node's compatible property.
+ *
+ * Returns true if the root node has the given value in its
+ * compatible property.
+ */
+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);
+
+/**
+ * of_device_is_available - check if a device is available for use
+ *
+ * @device: Node to check for availability
+ *
+ * Returns 1 if the status property is absent or set to "okay" or "ok",
+ * 0 otherwise
+ */
+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);
+
+/**
+ * of_get_parent - Get a node's parent if any
+ * @node: Node to get parent
+ *
+ * Returns a node pointer with refcount incremented, use
+ * of_node_put() on it when done.
+ */
+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);
+
+/**
+ * of_get_next_parent - Iterate to a node's parent
+ * @node: Node to get parent of
+ *
+ * This is like of_get_parent() except that it drops the
+ * refcount on the passed node, making it suitable for iterating
+ * through a node's parents.
+ *
+ * Returns a node pointer with refcount incremented, use
+ * of_node_put() on it when done.
+ */
+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;
+}
+
+/**
+ * of_get_next_child - Iterate a node childs
+ * @node: parent node
+ * @prev: previous child of the parent node, or NULL to get first
+ *
+ * Returns a node pointer with refcount incremented, use
+ * of_node_put() on it when done.
+ */
+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);
+
+/**
+ * of_find_node_by_path - Find a node matching a full OF path
+ * @path: The full path to match
+ *
+ * Returns a node pointer with refcount incremented, use
+ * of_node_put() on it when done.
+ */
+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);
+
+/**
+ * of_find_node_by_name - Find a node by its "name" property
+ * @from: The node to start searching from or NULL, the node
+ * you pass will not be searched, only the next one
+ * will; typically, you pass what the previous call
+ * returned. of_node_put() will be called on it
+ * @name: The name string to match against
+ *
+ * Returns a node pointer with refcount incremented, use
+ * of_node_put() on it when done.
+ */
+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);
+
+/**
+ * of_find_node_by_type - Find a node by its "device_type" property
+ * @from: The node to start searching from, or NULL to start searching
+ * the entire device tree. The node you pass will not be
+ * searched, only the next one will; typically, you pass
+ * what the previous call returned. of_node_put() will be
+ * called on from for you.
+ * @type: The type string to match against
+ *
+ * Returns a node pointer with refcount incremented, use
+ * of_node_put() on it when done.
+ */
+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);
+
+/**
+ * of_find_compatible_node - Find a node based on type and one of the
+ * tokens in its "compatible" property
+ * @from: The node to start searching from or NULL, the node
+ * you pass will not be searched, only the next one
+ * will; typically, you pass what the previous call
+ * returned. of_node_put() will be called on it
+ * @type: The type string to match "device_type" or NULL to ignore
+ * @compatible: The string to match to one of the tokens in the device
+ * "compatible" list.
+ *
+ * Returns a node pointer with refcount incremented, use
+ * of_node_put() on it when done.
+ */
+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);
+
+/**
+ * of_find_node_with_property - Find a node which has a property with
+ * the given name.
+ * @from: The node to start searching from or NULL, the node
+ * you pass will not be searched, only the next one
+ * will; typically, you pass what the previous call
+ * returned. of_node_put() will be called on it
+ * @prop_name: The name of the property to look for.
+ *
+ * Returns a node pointer with refcount incremented, use
+ * of_node_put() on it when done.
+ */
+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 != 0; 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);
+
+/**
+ * of_match_node - Tell if an device_node has a matching of_match structure
+ * @matches: array of of device match structures to search in
+ * @node: the of device structure to match against
+ *
+ * Low level utility function used by device matching.
+ */
+const struct of_device_id *of_match_node(const struct of_device_id *matches,
+ const struct device_node *node)
+{
+ 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);
+
+/**
+ * of_find_matching_node - Find a node based on an of_device_id match
+ * table.
+ * @from: The node to start searching from or NULL, the node
+ * you pass will not be searched, only the next one
+ * will; typically, you pass what the previous call
+ * returned. of_node_put() will be called on it
+ * @matches: array of of device match structures to search in
+ *
+ * Returns a node pointer with refcount incremented, use
+ * of_node_put() on it when done.
+ */
+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);
+
+/**
+ * of_modalias_table: Table of explicit compatible ==> modalias mappings
+ *
+ * This table allows particulare compatible property values to be mapped
+ * to modalias strings. This is useful for busses which do not directly
+ * understand the OF device tree but are populated based on data contained
+ * within the device tree. SPI and I2C are the two current users of this
+ * table.
+ *
+ * In most cases, devices do not need to be listed in this table because
+ * the modalias value can be derived directly from the compatible table.
+ * However, if for any reason a value cannot be derived, then this table
+ * provides a method to override the implicit derivation.
+ *
+ * At the moment, a single table is used for all bus types because it is
+ * assumed that the data size is small and that the compatible values
+ * should already be distinct enough to differentiate between SPI, I2C
+ * and other devices.
+ */
+struct of_modalias_table {
+ char *of_device;
+ char *modalias;
+};
+static struct of_modalias_table of_modalias_table[] = {
+ { "fsl,mcu-mpc8349emitx", "mcu-mpc8349emitx" },
+ { "mmc-spi-slot", "mmc_spi" },
+};
+
+/**
+ * of_modalias_node - Lookup appropriate modalias for a device node
+ * @node: pointer to a device tree node
+ * @modalias: Pointer to buffer that modalias value will be copied into
+ * @len: Length of modalias value
+ *
+ * Based on the value of the compatible property, this routine will determine
+ * an appropriate modalias value for a particular device tree node. Two
+ * separate methods are attempted to derive a modalias value.
+ *
+ * First method is to lookup the compatible value in of_modalias_table.
+ * Second is to strip off the manufacturer prefix from the first
+ * compatible entry and use the remainder as modalias
+ *
+ * This routine returns 0 on success
+ */
+int of_modalias_node(struct device_node *node, char *modalias, int len)
+{
+ int i, cplen;
+ const char *compatible;
+ const char *p;
+
+ /* 1. search for exception list entry */
+ for (i = 0; i < ARRAY_SIZE(of_modalias_table); i++) {
+ compatible = of_modalias_table[i].of_device;
+ if (!of_device_is_compatible(node, compatible))
+ continue;
+ strlcpy(modalias, of_modalias_table[i].modalias, len);
+ return 0;
+ }
+
+ compatible = of_get_property(node, "compatible", &cplen);
+ if (!compatible)
+ return -ENODEV;
+
+ /* 2. take first compatible entry and strip manufacturer */
+ p = strchr(compatible, ',');
+ if (!p)
+ return -ENODEV;
+ p++;
+ strlcpy(modalias, p, len);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(of_modalias_node);
+
+/**
+ * of_find_node_by_phandle - Find a node given a phandle
+ * @handle: phandle of the node to find
+ *
+ * Returns a node pointer with refcount incremented, use
+ * of_node_put() on it when done.
+ */
+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);
+
+/**
+ * of_parse_phandle - Resolve a phandle property to a device_node pointer
+ * @np: Pointer to device node holding phandle property
+ * @phandle_name: Name of property holding a phandle value
+ * @index: For properties holding a table of phandles, this is the index into
+ * the table
+ *
+ * Returns the device_node pointer with refcount incremented. Use
+ * of_node_put() on it when done.
+ */
+struct device_node *
+of_parse_phandle(struct device_node *np, const char *phandle_name, int index)
+{
+ const phandle *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(phandle[index]);
+}
+EXPORT_SYMBOL(of_parse_phandle);
+
+/**
+ * of_parse_phandles_with_args - Find a node pointed by phandle in a list
+ * @np: pointer to a device tree node containing a list
+ * @list_name: property name that contains a list
+ * @cells_name: property name that specifies phandles' arguments count
+ * @index: index of a phandle to parse out
+ * @out_node: optional pointer to device_node struct pointer (will be filled)
+ * @out_args: optional pointer to arguments pointer (will be filled)
+ *
+ * This function is useful to parse lists of phandles and their arguments.
+ * Returns 0 on success and fills out_node and out_args, on error returns
+ * appropriate errno value.
+ *
+ * Example:
+ *
+ * phandle1: node1 {
+ * #list-cells = <2>;
+ * }
+ *
+ * phandle2: node2 {
+ * #list-cells = <1>;
+ * }
+ *
+ * node3 {
+ * list = <&phandle1 1 2 &phandle2 3>;
+ * }
+ *
+ * To get a device_node of the `node2' node you may call this:
+ * of_parse_phandles_with_args(node3, "list", "#list-cells", 2, &node2, &args);
+ */
+int of_parse_phandles_with_args(struct device_node *np, const char *list_name,
+ const char *cells_name, int index,
+ struct device_node **out_node,
+ const void **out_args)
+{
+ int ret = -EINVAL;
+ const __be32 *list;
+ const __be32 *list_end;
+ int size;
+ int cur_index = 0;
+ struct device_node *node = NULL;
+ const void *args = NULL;
+
+ list = of_get_property(np, list_name, &size);
+ if (!list) {
+ ret = -ENOENT;
+ goto err0;
+ }
+ list_end = list + size / sizeof(*list);
+
+ while (list < list_end) {
+ const __be32 *cells;
+ const phandle *phandle;
+
+ phandle = list++;
+ args = list;
+
+ /* one cell hole in the list = <>; */
+ if (!*phandle)
+ goto next;
+
+ node = of_find_node_by_phandle(*phandle);
+ if (!node) {
+ pr_debug("%s: could not find phandle\n",
+ np->full_name);
+ goto err0;
+ }
+
+ cells = of_get_property(node, cells_name, &size);
+ if (!cells || size != sizeof(*cells)) {
+ pr_debug("%s: could not get %s for %s\n",
+ np->full_name, cells_name, node->full_name);
+ goto err1;
+ }
+
+ list += be32_to_cpup(cells);
+ if (list > list_end) {
+ pr_debug("%s: insufficient arguments length\n",
+ np->full_name);
+ goto err1;
+ }
+next:
+ if (cur_index == index)
+ break;
+
+ of_node_put(node);
+ node = NULL;
+ args = NULL;
+ cur_index++;
+ }
+
+ if (!node) {
+ /*
+ * args w/o node indicates that the loop above has stopped at
+ * the 'hole' cell. Report this differently.
+ */
+ if (args)
+ ret = -EEXIST;
+ else
+ ret = -ENOENT;
+ goto err0;
+ }
+
+ if (out_node)
+ *out_node = node;
+ if (out_args)
+ *out_args = args;
+
+ return 0;
+err1:
+ of_node_put(node);
+err0:
+ pr_debug("%s failed with status %d\n", __func__, ret);
+ return ret;
+}
+EXPORT_SYMBOL(of_parse_phandles_with_args);
+
+/**
+ * prom_add_property - Add a property to a node
+ */
+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;
+}
+
+/**
+ * prom_remove_property - Remove a property from a node.
+ *
+ * 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, so it won't be found any more.
+ */
+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.
+ *
+ * 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 *oldprop)
+{
+ struct property **next;
+ unsigned long flags;
+ int found = 0;
+
+ 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.
+ */
+
+/**
+ * of_attach_node - Plug a device node into the tree and global list.
+ */
+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);
+}
+
+/**
+ * of_detach_node - "Unplug" a node from the device tree.
+ *
+ * The caller must hold a reference to the node. The memory associated with
+ * the node is not freed until its refcount goes to zero.
+ */
+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) */
+
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff