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);