* 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 - Alias property in 'aliases' node
+ * @link: List node to link the structure in aliases_lookup list
+ * @alias: Alias property name
+ * @np: Pointer to device_node that the alias stands for
+ * @id: Index value from end of alias name
+ * @stem: Alias string without the index
+ *
+ * The structure represents one alias property of 'aliases' node as
+ * an entry in aliases_lookup list.
+ */
+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.
}
EXPORT_SYMBOL_GPL(of_property_read_u32_array);
+/**
+ * of_property_read_u64 - Find and read a 64 bit integer from a property
+ * @np: device node from which the property value is to be read.
+ * @propname: name of the property to be searched.
+ * @out_value: pointer to return value, modified only if return value is 0.
+ *
+ * Search for a property in a device node and read a 64-bit value from
+ * it. Returns 0 on success, -EINVAL if the property does not exist,
+ * -ENODATA if property does not have a value, and -EOVERFLOW if the
+ * property data isn't large enough.
+ *
+ * The out_value is modified only if a valid u64 value can be decoded.
+ */
+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);
+
/**
* of_property_read_string - Find and read a string from a property
* @np: device node from which the property value is to be read.
}
#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, np ? np->full_name : NULL);
+}
+
+/**
+ * of_alias_scan - Scan all properties of 'aliases' node
+ *
+ * The function scans all the properties of 'aliases' node and populate
+ * the the global lookup table with the properties. It returns the
+ * number of alias_prop found, or error code in error case.
+ *
+ * @dt_alloc: An allocator that provides a virtual address to memory
+ * for the resulting tree
+ */
+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(pp, of_aliases->properties) {
+ 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);
+ }
+}
+
+/**
+ * of_alias_get_id - Get alias id for the given device_node
+ * @np: Pointer to the given device_node
+ * @stem: Alias stem of the given device_node
+ *
+ * The function travels the lookup table to get alias id for the given
+ * device_node and alias stem. It returns the alias id if find it.
+ */
+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);
git.openpandora.org / pandora-kernel.git / blobdiff