/*
 * tree.c: Basic device tree traversal/scanning for the Linux
 *         prom library.
 *
 * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
 * Copyright (C) 1996,1997 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
 */

#include <linux/string.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/module.h>

#include <asm/openprom.h>
#include <asm/oplib.h>
#include <asm/ldc.h>

/* Return the child of node 'node' or zero if no this node has no
 * direct descendent.
 */
inline int __prom_getchild(int node)
{
        return p1275_cmd ("child", P1275_INOUT(1, 1), node);
}

inline int prom_getchild(int node)
{
        int cnode;

        if(node == -1) return 0;
        cnode = __prom_getchild(node);
        if(cnode == -1) return 0;
        return (int)cnode;
}
EXPORT_SYMBOL(prom_getchild);

inline int prom_getparent(int node)
{
        int cnode;

        if(node == -1) return 0;
        cnode = p1275_cmd ("parent", P1275_INOUT(1, 1), node);
        if(cnode == -1) return 0;
        return (int)cnode;
}

/* Return the next sibling of node 'node' or zero if no more siblings
 * at this level of depth in the tree.
 */
inline int __prom_getsibling(int node)
{
        return p1275_cmd(prom_peer_name, P1275_INOUT(1, 1), node);
}

inline int prom_getsibling(int node)
{
        int sibnode;

        if (node == -1)
                return 0;
        sibnode = __prom_getsibling(node);
        if (sibnode == -1)
                return 0;

        return sibnode;
}
EXPORT_SYMBOL(prom_getsibling);

/* Return the length in bytes of property 'prop' at node 'node'.
 * Return -1 on error.
 */
inline int prom_getproplen(int node, const char *prop)
{
        if((!node) || (!prop)) return -1;
        return p1275_cmd ("getproplen", 
                          P1275_ARG(1,P1275_ARG_IN_STRING)|
                          P1275_INOUT(2, 1), 
                          node, prop);
}
EXPORT_SYMBOL(prom_getproplen);

/* Acquire a property 'prop' at node 'node' and place it in
 * 'buffer' which has a size of 'bufsize'.  If the acquisition
 * was successful the length will be returned, else -1 is returned.
 */
inline int prom_getproperty(int node, const char *prop,
                            char *buffer, int bufsize)
{
        int plen;

        plen = prom_getproplen(node, prop);
        if ((plen > bufsize) || (plen == 0) || (plen == -1)) {
                return -1;
        } else {
                /* Ok, things seem all right. */
                return p1275_cmd(prom_getprop_name, 
                                 P1275_ARG(1,P1275_ARG_IN_STRING)|
                                 P1275_ARG(2,P1275_ARG_OUT_BUF)|
                                 P1275_INOUT(4, 1), 
                                 node, prop, buffer, P1275_SIZE(plen));
        }
}
EXPORT_SYMBOL(prom_getproperty);

/* Acquire an integer property and return its value.  Returns -1
 * on failure.
 */
inline int prom_getint(int node, const char *prop)
{
        int intprop;

        if(prom_getproperty(node, prop, (char *) &intprop, sizeof(int)) != -1)
                return intprop;

        return -1;
}
EXPORT_SYMBOL(prom_getint);

/* Acquire an integer property, upon error return the passed default
 * integer.
 */

int prom_getintdefault(int node, const char *property, int deflt)
{
        int retval;

        retval = prom_getint(node, property);
        if(retval == -1) return deflt;

        return retval;
}
EXPORT_SYMBOL(prom_getintdefault);

/* Acquire a boolean property, 1=TRUE 0=FALSE. */
int prom_getbool(int node, const char *prop)
{
        int retval;

        retval = prom_getproplen(node, prop);
        if(retval == -1) return 0;
        return 1;
}
EXPORT_SYMBOL(prom_getbool);

/* Acquire a property whose value is a string, returns a null
 * string on error.  The char pointer is the user supplied string
 * buffer.
 */
void prom_getstring(int node, const char *prop, char *user_buf, int ubuf_size)
{
        int len;

        len = prom_getproperty(node, prop, user_buf, ubuf_size);
        if(len != -1) return;
        user_buf[0] = 0;
        return;
}
EXPORT_SYMBOL(prom_getstring);

/* Does the device at node 'node' have name 'name'?
 * YES = 1   NO = 0
 */
int prom_nodematch(int node, const char *name)
{
        char namebuf[128];
        prom_getproperty(node, "name", namebuf, sizeof(namebuf));
        if(strcmp(namebuf, name) == 0) return 1;
        return 0;
}

/* Search siblings at 'node_start' for a node with name
 * 'nodename'.  Return node if successful, zero if not.
 */
int prom_searchsiblings(int node_start, const char *nodename)
{

        int thisnode, error;
        char promlib_buf[128];

        for(thisnode = node_start; thisnode;
            thisnode=prom_getsibling(thisnode)) {
                error = prom_getproperty(thisnode, "name", promlib_buf,
                                         sizeof(promlib_buf));
                /* Should this ever happen? */
                if(error == -1) continue;
                if(strcmp(nodename, promlib_buf)==0) return thisnode;
        }

        return 0;
}
EXPORT_SYMBOL(prom_searchsiblings);

/* Return the first property type for node 'node'.
 * buffer should be at least 32B in length
 */
inline char *prom_firstprop(int node, char *buffer)
{
        *buffer = 0;
        if(node == -1) return buffer;
        p1275_cmd ("nextprop", P1275_ARG(2,P1275_ARG_OUT_32B)|
                               P1275_INOUT(3, 0), 
                               node, (char *) 0x0, buffer);
        return buffer;
}
EXPORT_SYMBOL(prom_firstprop);

/* Return the property type string after property type 'oprop'
 * at node 'node' .  Returns NULL string if no more
 * property types for this node.
 */
inline char *prom_nextprop(int node, const char *oprop, char *buffer)
{
        char buf[32];

        if(node == -1) {
                *buffer = 0;
                return buffer;
        }
        if (oprop == buffer) {
                strcpy (buf, oprop);
                oprop = buf;
        }
        p1275_cmd ("nextprop", P1275_ARG(1,P1275_ARG_IN_STRING)|
                                    P1275_ARG(2,P1275_ARG_OUT_32B)|
                                    P1275_INOUT(3, 0), 
                                    node, oprop, buffer); 
        return buffer;
}
EXPORT_SYMBOL(prom_nextprop);

int
prom_finddevice(const char *name)
{
        if (!name)
                return 0;
        return p1275_cmd(prom_finddev_name,
                         P1275_ARG(0,P1275_ARG_IN_STRING)|
                         P1275_INOUT(1, 1), 
                         name);
}
EXPORT_SYMBOL(prom_finddevice);

int prom_node_has_property(int node, const char *prop)
{
        char buf [32];
        
        *buf = 0;
        do {
                prom_nextprop(node, buf, buf);
                if(!strcmp(buf, prop))
                        return 1;
        } while (*buf);
        return 0;
}
EXPORT_SYMBOL(prom_node_has_property);

/* Set property 'pname' at node 'node' to value 'value' which has a length
 * of 'size' bytes.  Return the number of bytes the prom accepted.
 */
int
prom_setprop(int node, const char *pname, char *value, int size)
{
        if (size == 0)
                return 0;
        if ((pname == 0) || (value == 0))
                return 0;
        
#ifdef CONFIG_SUN_LDOMS
        if (ldom_domaining_enabled) {
                ldom_set_var(pname, value);
                return 0;
        }
#endif
        return p1275_cmd ("setprop", P1275_ARG(1,P1275_ARG_IN_STRING)|
                                          P1275_ARG(2,P1275_ARG_IN_BUF)|
                                          P1275_INOUT(4, 1), 
                                          node, pname, value, P1275_SIZE(size));
}
EXPORT_SYMBOL(prom_setprop);

inline int prom_inst2pkg(int inst)
{
        int node;
        
        node = p1275_cmd ("instance-to-package", P1275_INOUT(1, 1), inst);
        if (node == -1) return 0;
        return node;
}

/* Return 'node' assigned to a particular prom 'path'
 * FIXME: Should work for v0 as well
 */
int
prom_pathtoinode(const char *path)
{
        int node, inst;

        inst = prom_devopen (path);
        if (inst == 0) return 0;
        node = prom_inst2pkg (inst);
        prom_devclose (inst);
        if (node == -1) return 0;
        return node;
}

int prom_ihandle2path(int handle, char *buffer, int bufsize)
{
        return p1275_cmd("instance-to-path",
                         P1275_ARG(1,P1275_ARG_OUT_BUF)|
                         P1275_INOUT(3, 1),
                         handle, buffer, P1275_SIZE(bufsize));
}