libfdt: Add phandle generation helper

[thirdparty/u-boot.git] / scripts / dtc / libfdt / libfdt.h

diff --git a/scripts/dtc/libfdt/libfdt.h b/scripts/dtc/libfdt/libfdt.h
index fd73688f9e9f3e03e7298eb74db50439d5b2ab3d..cf86ddba88113f22f989c3041b8025193b69d71d 100644 (file)
--- a/scripts/dtc/libfdt/libfdt.h
+++ b/scripts/dtc/libfdt/libfdt.h
@@ -139,6 +139,10 @@
 
 #define FDT_ERR_MAX            17
 
+/* constants */
+#define FDT_MAX_PHANDLE 0xfffffffe
+       /* Valid values for phandles range from 1 to 2^32-2. */
+
 /**********************************************************************/
 /* Low-level functions (you probably don't need these)                */
 /**********************************************************************/
@@ -313,6 +317,21 @@ const char *fdt_string(const void *fdt, int stroffset);
  */
 uint32_t fdt_get_max_phandle(const void *fdt);
 
+/**
+ * fdt_generate_phandle - return a new, unused phandle for a device tree blob
+ * @fdt: pointer to the device tree blob
+ * @phandle: return location for the new phandle
+ *
+ * Walks the device tree blob and looks for the highest phandle value. On
+ * success, the new, unused phandle value (one higher than the previously
+ * highest phandle value in the device tree blob) will be returned in the
+ * @phandle parameter.
+ *
+ * Returns:
+ *   0 on success or a negative error-code on failure
+ */
+int fdt_generate_phandle(const void *fdt, uint32_t *phandle);
+
 /**
  * fdt_num_mem_rsv - retrieve the number of memory reserve map entries
  * @fdt: pointer to the device tree blob