2 * tree.c: Basic device tree traversal/scanning for the Linux
5 * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
8 #include <linux/string.h>
9 #include <linux/types.h>
10 #include <linux/kernel.h>
11 #include <linux/sched.h>
12 #include <linux/ctype.h>
13 #include <linux/module.h>
15 #include <asm/openprom.h>
16 #include <asm/oplib.h>
18 extern void restore_current(void);
20 static char promlib_buf
[128];
22 /* Internal version of prom_getchild that does not alter return values. */
23 static phandle
__prom_getchild(phandle node
)
28 spin_lock_irqsave(&prom_lock
, flags
);
29 cnode
= prom_nodeops
->no_child(node
);
31 spin_unlock_irqrestore(&prom_lock
, flags
);
36 /* Return the child of node 'node' or zero if no this node has no
39 phandle
prom_getchild(phandle node
)
46 cnode
= __prom_getchild(node
);
47 if (cnode
== 0 || (s32
)cnode
== -1)
52 EXPORT_SYMBOL(prom_getchild
);
54 /* Internal version of prom_getsibling that does not alter return values. */
55 static phandle
__prom_getsibling(phandle node
)
60 spin_lock_irqsave(&prom_lock
, flags
);
61 cnode
= prom_nodeops
->no_nextnode(node
);
63 spin_unlock_irqrestore(&prom_lock
, flags
);
68 /* Return the next sibling of node 'node' or zero if no more siblings
69 * at this level of depth in the tree.
71 phandle
prom_getsibling(phandle node
)
78 sibnode
= __prom_getsibling(node
);
79 if (sibnode
== 0 || (s32
)sibnode
== -1)
84 EXPORT_SYMBOL(prom_getsibling
);
86 /* Return the length in bytes of property 'prop' at node 'node'.
89 int prom_getproplen(phandle node
, const char *prop
)
94 if((!node
) || (!prop
))
97 spin_lock_irqsave(&prom_lock
, flags
);
98 ret
= prom_nodeops
->no_proplen(node
, prop
);
100 spin_unlock_irqrestore(&prom_lock
, flags
);
103 EXPORT_SYMBOL(prom_getproplen
);
105 /* Acquire a property 'prop' at node 'node' and place it in
106 * 'buffer' which has a size of 'bufsize'. If the acquisition
107 * was successful the length will be returned, else -1 is returned.
109 int prom_getproperty(phandle node
, const char *prop
, char *buffer
, int bufsize
)
114 plen
= prom_getproplen(node
, prop
);
115 if((plen
> bufsize
) || (plen
== 0) || (plen
== -1))
117 /* Ok, things seem all right. */
118 spin_lock_irqsave(&prom_lock
, flags
);
119 ret
= prom_nodeops
->no_getprop(node
, prop
, buffer
);
121 spin_unlock_irqrestore(&prom_lock
, flags
);
124 EXPORT_SYMBOL(prom_getproperty
);
126 /* Acquire an integer property and return its value. Returns -1
129 int prom_getint(phandle node
, char *prop
)
133 if(prom_getproperty(node
, prop
, (char *) &intprop
, sizeof(int)) != -1)
138 EXPORT_SYMBOL(prom_getint
);
140 /* Acquire an integer property, upon error return the passed default
143 int prom_getintdefault(phandle node
, char *property
, int deflt
)
147 retval
= prom_getint(node
, property
);
148 if(retval
== -1) return deflt
;
152 EXPORT_SYMBOL(prom_getintdefault
);
154 /* Acquire a boolean property, 1=TRUE 0=FALSE. */
155 int prom_getbool(phandle node
, char *prop
)
159 retval
= prom_getproplen(node
, prop
);
160 if(retval
== -1) return 0;
163 EXPORT_SYMBOL(prom_getbool
);
165 /* Acquire a property whose value is a string, returns a null
166 * string on error. The char pointer is the user supplied string
169 void prom_getstring(phandle node
, char *prop
, char *user_buf
, int ubuf_size
)
173 len
= prom_getproperty(node
, prop
, user_buf
, ubuf_size
);
174 if(len
!= -1) return;
177 EXPORT_SYMBOL(prom_getstring
);
180 /* Search siblings at 'node_start' for a node with name
181 * 'nodename'. Return node if successful, zero if not.
183 phandle
prom_searchsiblings(phandle node_start
, char *nodename
)
189 for(thisnode
= node_start
; thisnode
;
190 thisnode
=prom_getsibling(thisnode
)) {
191 error
= prom_getproperty(thisnode
, "name", promlib_buf
,
192 sizeof(promlib_buf
));
193 /* Should this ever happen? */
194 if(error
== -1) continue;
195 if(strcmp(nodename
, promlib_buf
)==0) return thisnode
;
200 EXPORT_SYMBOL(prom_searchsiblings
);
202 /* Interal version of nextprop that does not alter return values. */
203 static char *__prom_nextprop(phandle node
, char * oprop
)
208 spin_lock_irqsave(&prom_lock
, flags
);
209 prop
= prom_nodeops
->no_nextprop(node
, oprop
);
211 spin_unlock_irqrestore(&prom_lock
, flags
);
216 /* Return the property type string after property type 'oprop'
217 * at node 'node' . Returns empty string if no more
218 * property types for this node.
220 char *prom_nextprop(phandle node
, char *oprop
, char *buffer
)
222 if (node
== 0 || (s32
)node
== -1)
225 return __prom_nextprop(node
, oprop
);
227 EXPORT_SYMBOL(prom_nextprop
);
229 phandle
prom_finddevice(char *name
)
233 phandle node
= prom_root_node
, node2
;
234 unsigned int which_io
, phys_addr
;
235 struct linux_prom_registers reg
[PROMREG_MAX
];
238 if (!*s
) return node
; /* path '.../' is legal */
239 node
= prom_getchild(node
);
241 for (d
= nbuf
; *s
!= 0 && *s
!= '@' && *s
!= '/';)
245 node
= prom_searchsiblings(node
, nbuf
);
250 if (isxdigit(s
[1]) && s
[2] == ',') {
251 which_io
= simple_strtoul(s
+1, NULL
, 16);
252 phys_addr
= simple_strtoul(s
+3, &d
, 16);
253 if (d
!= s
+ 3 && (!*d
|| *d
== '/')
256 while (node2
&& (s32
)node2
!= -1) {
257 if (prom_getproperty (node2
, "reg", (char *)reg
, sizeof (reg
)) > 0) {
258 if (which_io
== reg
[0].which_io
&& phys_addr
== reg
[0].phys_addr
) {
263 node2
= prom_getsibling(node2
);
264 if (!node2
|| (s32
)node2
== -1)
266 node2
= prom_searchsiblings(prom_getsibling(node2
), nbuf
);
270 while (*s
!= 0 && *s
!= '/') s
++;
275 EXPORT_SYMBOL(prom_finddevice
);
277 /* Set property 'pname' at node 'node' to value 'value' which has a length
278 * of 'size' bytes. Return the number of bytes the prom accepted.
280 int prom_setprop(phandle node
, const char *pname
, char *value
, int size
)
287 if ((pname
== NULL
) || (value
== NULL
))
289 spin_lock_irqsave(&prom_lock
, flags
);
290 ret
= prom_nodeops
->no_setprop(node
, pname
, value
, size
);
292 spin_unlock_irqrestore(&prom_lock
, flags
);
295 EXPORT_SYMBOL(prom_setprop
);
297 phandle
prom_inst2pkg(int inst
)
302 spin_lock_irqsave(&prom_lock
, flags
);
303 node
= (*romvec
->pv_v2devops
.v2_inst2pkg
)(inst
);
305 spin_unlock_irqrestore(&prom_lock
, flags
);