fdt: Add function to alloc phandle values

If we are creating reference (handles) to nodes in a device tree we need
to first create a new phandle in node and this needs a new phandle
value.  So we search through the whole dtb to find the max phandle value
and return the next greater value for a new phandle allocation.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Acked-by: Gerald Van Baren <vanbaren@cideas.com>
This commit is contained in:
Kumar Gala 2010-07-09 16:18:58 -05:00
parent 6aba33e939
commit b4b847e951
2 changed files with 19 additions and 0 deletions

View file

@ -1151,4 +1151,22 @@ int fdt_node_offset_by_compat_reg(void *blob, const char *compat,
return -FDT_ERR_NOTFOUND;
}
/**
* fdt_alloc_phandle: Return next free phandle value
*
* @blob: ptr to device tree
*/
int fdt_alloc_phandle(void *blob)
{
int offset, len, phandle = 0;
const u32 *val;
for (offset = fdt_next_node(blob, -1, NULL); offset >= 0;
offset = fdt_next_node(blob, offset, NULL)) {
val = fdt_getprop(blob, offset, "linux,phandle", &len);
if (val)
phandle = max(*val, phandle);
}
return phandle + 1;
}

View file

@ -86,6 +86,7 @@ void fdt_del_node_and_alias(void *blob, const char *alias);
u64 fdt_translate_address(void *blob, int node_offset, const u32 *in_addr);
int fdt_node_offset_by_compat_reg(void *blob, const char *compat,
phys_addr_t compat_off);
int fdt_alloc_phandle(void *blob);
#endif /* ifdef CONFIG_OF_LIBFDT */
#endif /* ifndef __FDT_SUPPORT_H */