diff options
Diffstat (limited to 'drivers/of/base.c')
-rw-r--r-- | drivers/of/base.c | 65 |
1 files changed, 65 insertions, 0 deletions
diff --git a/drivers/of/base.c b/drivers/of/base.c new file mode 100644 index 000000000000..723d80d704e0 --- /dev/null +++ b/drivers/of/base.c | |||
@@ -0,0 +1,65 @@ | |||
1 | /* | ||
2 | * Procedures for creating, accessing and interpreting the device tree. | ||
3 | * | ||
4 | * Paul Mackerras August 1996. | ||
5 | * Copyright (C) 1996-2005 Paul Mackerras. | ||
6 | * | ||
7 | * Adapted for 64bit PowerPC by Dave Engebretsen and Peter Bergner. | ||
8 | * {engebret|bergner}@us.ibm.com | ||
9 | * | ||
10 | * Adapted for sparc and sparc64 by David S. Miller davem@davemloft.net | ||
11 | * | ||
12 | * Reconsolidated from arch/x/kernel/prom.c by Stephen Rothwell. | ||
13 | * | ||
14 | * This program is free software; you can redistribute it and/or | ||
15 | * modify it under the terms of the GNU General Public License | ||
16 | * as published by the Free Software Foundation; either version | ||
17 | * 2 of the License, or (at your option) any later version. | ||
18 | */ | ||
19 | #include <linux/module.h> | ||
20 | #include <linux/of.h> | ||
21 | |||
22 | int of_n_addr_cells(struct device_node *np) | ||
23 | { | ||
24 | const int *ip; | ||
25 | |||
26 | do { | ||
27 | if (np->parent) | ||
28 | np = np->parent; | ||
29 | ip = of_get_property(np, "#address-cells", NULL); | ||
30 | if (ip) | ||
31 | return *ip; | ||
32 | } while (np->parent); | ||
33 | /* No #address-cells property for the root node */ | ||
34 | return OF_ROOT_NODE_ADDR_CELLS_DEFAULT; | ||
35 | } | ||
36 | EXPORT_SYMBOL(of_n_addr_cells); | ||
37 | |||
38 | int of_n_size_cells(struct device_node *np) | ||
39 | { | ||
40 | const int *ip; | ||
41 | |||
42 | do { | ||
43 | if (np->parent) | ||
44 | np = np->parent; | ||
45 | ip = of_get_property(np, "#size-cells", NULL); | ||
46 | if (ip) | ||
47 | return *ip; | ||
48 | } while (np->parent); | ||
49 | /* No #size-cells property for the root node */ | ||
50 | return OF_ROOT_NODE_SIZE_CELLS_DEFAULT; | ||
51 | } | ||
52 | EXPORT_SYMBOL(of_n_size_cells); | ||
53 | |||
54 | /* | ||
55 | * Find a property with a given name for a given node | ||
56 | * and return the value. | ||
57 | */ | ||
58 | const void *of_get_property(const struct device_node *np, const char *name, | ||
59 | int *lenp) | ||
60 | { | ||
61 | struct property *pp = of_find_property(np, name, lenp); | ||
62 | |||
63 | return pp ? pp->value : NULL; | ||
64 | } | ||
65 | EXPORT_SYMBOL(of_get_property); | ||