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-rw-r--r--drivers/of/base.c65
1 files changed, 65 insertions, 0 deletions
diff --git a/drivers/of/base.c b/drivers/of/base.c
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index 0000000..723d80d
--- /dev/null
+++ b/drivers/of/base.c
@@ -0,0 +1,65 @@
+/*
+ * 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 davem@davemloft.net
+ *
+ * Reconsolidated from arch/x/kernel/prom.c by Stephen Rothwell.
+ *
+ * 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/of.h>
+
+int of_n_addr_cells(struct device_node *np)
+{
+ const int *ip;
+
+ do {
+ if (np->parent)
+ np = np->parent;
+ ip = of_get_property(np, "#address-cells", NULL);
+ if (ip)
+ return *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 int *ip;
+
+ do {
+ if (np->parent)
+ np = np->parent;
+ ip = of_get_property(np, "#size-cells", NULL);
+ if (ip)
+ return *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);
+
+/*
+ * 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);
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