*/
#include <linux/module.h>
#include <linux/of.h>
+#include <linux/spinlock.h>
+
+struct device_node *allnodes;
+
+/* 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)
{
}
EXPORT_SYMBOL(of_n_size_cells);
+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) {
+ if (lenp != 0)
+ *lenp = pp->length;
+ break;
+ }
+ }
+ read_unlock(&devtree_lock);
+
+ return pp;
+}
+EXPORT_SYMBOL(of_find_property);
+
/*
* Find a property with a given name for a given node
* and return the value.
return 0;
}
EXPORT_SYMBOL(of_device_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_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[] = {
+ /* Empty for now; add entries as needed */
+};
+
+/**
+ * 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. Three
+ * separate methods are used to derive a modalias value.
+ *
+ * First method is to lookup the compatible value in of_modalias_table.
+ * Second is to look for a "linux,<modalias>" entry in the compatible list
+ * and used that for modalias. Third 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. search for linux,<modalias> entry */
+ p = compatible;
+ while (cplen > 0) {
+ if (!strncmp(p, "linux,", 6)) {
+ p += 6;
+ strlcpy(modalias, p, len);
+ return 0;
+ }
+
+ i = strlen(p) + 1;
+ p += i;
+ cplen -= i;
+ }
+
+ /* 3. 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);
+