/*
* proc_devtree.c - handles /proc/device-tree
*
* Copyright 1997 Paul Mackerras
*/
#include <linux/errno.h>
#include <linux/time.h>
#include <linux/proc_fs.h>
#include <linux/stat.h>
#include <linux/string.h>
#include <asm/prom.h>
#include <asm/uaccess.h>
#ifndef HAVE_ARCH_DEVTREE_FIXUPS
static inline void set_node_proc_entry(struct device_node *np,
struct proc_dir_entry *de)
{
}
#endif
static struct proc_dir_entry *proc_device_tree;
/*
* Supply data on a read from /proc/device-tree/node/property.
*/
static int property_read_proc(char *page, char **start, off_t off,
int count, int *eof, void *data)
{
struct property *pp = data;
int n;
if (off >= pp->length) {
*eof = 1;
return 0;
}
n = pp->length - off;
if (n > count)
n = count;
else
*eof = 1;
memcpy(page, pp->value + off, n);
*start = page;
return n;
}
/*
* For a node with a name like "gc@10", we make symlinks called "gc"
* and "@10" to it.
*/
/*
* Process a node, adding entries for its children and its properties.
*/
void proc_device_tree_add_node(struct device_node *np,
struct proc_dir_entry *de)
{
struct property *pp;
struct proc_dir_entry *ent;
struct device_node *child;
struct proc_dir_entry *list = NULL, **lastp;
const char *p;
set_node_proc_entry(np, de);
lastp = &list;
for (child = NULL; (child = of_get_next_child(np, child));) {
p = strrchr(child->full_name, '/');
if (!p)
p = child->full_name;
else
++p;
ent = proc_mkdir(p, de);
if (ent == 0)
break;
*lastp = ent;
ent->next = NULL;
lastp = &ent->next;
proc_device_tree_add_node(child, ent);
}
of_node_put(child);
for (pp = np->properties; pp != 0; pp = pp->next) {
/*
* Yet another Apple device-tree bogosity: on some machines,
* they have properties & nodes with the same name. Those
* properties are quite unimportant for us though, thus we
* simply "skip" them here, but we do have to check.
*/
for (ent = list; ent != NULL; ent = ent->next)
if (!strcmp(ent->name, pp->name))
break;
if (ent != NULL) {
printk(KERN_WARNING "device-tree: property \"%s\" name"
" conflicts with node in %s\n", pp->name,
np->full_name);
continue;
}
/*
* Unfortunately proc_register puts each new entry
* at the beginning of the list. So we rearrange them.
*/
ent = create_proc_read_entry(pp->name,
strncmp(pp->name, "security-", 9)
? S_IRUGO : S_IRUSR, de,
property_read_proc, pp);
if (ent == 0)
break;
if (!strncmp(pp->name, "security-", 9))
ent->size = 0; /* don't leak number of password chars */
else
ent->size = pp->length;
ent->next = NULL;
*lastp = ent;
lastp = &ent->next;
}
de->subdir = list;
}
/*
* Called on initialization to set up the /proc/device-tree subtree
*/
void proc_device_tree_init(void)
{
struct device_node *root;
if ( !have_of )
return;
proc_device_tree = proc_mkdir("device-tree", NULL);
if (proc_device_tree == 0)
return;
root = of_find_node_by_path("/");
if (root == 0) {
printk(KERN_ERR "/proc/device-tree: can't find root\n");
return;
}
proc_device_tree_add_node(root, proc_device_tree);
of_node_put(root);
}
