/* * Procedures for creating, accessing and interpreting the device tree. * * Paul Mackerras August 1996. * Copyright (C) 1996-2005 Paul Mackerras. * * Adapted for 64bit PowerPC by Dave Engebretsen and Peter Bergner. * {engebret|bergner}@us.ibm.com * * Adapted for sparc and sparc64 by David S. Miller davem@davemloft.net * * Reconsolidated from arch/x/kernel/prom.c by Stephen Rothwell. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. */ #include #include int of_n_addr_cells(struct device_node *np) { const int *ip; do { if (np->parent) np = np->parent; ip = of_get_property(np, "#address-cells", NULL); if (ip) return *ip; } while (np->parent); /* No #address-cells property for the root node */ return OF_ROOT_NODE_ADDR_CELLS_DEFAULT; } EXPORT_SYMBOL(of_n_addr_cells); int of_n_size_cells(struct device_node *np) { const int *ip; do { if (np->parent) np = np->parent; ip = of_get_property(np, "#size-cells", NULL); if (ip) return *ip; } while (np->parent); /* No #size-cells property for the root node */ return OF_ROOT_NODE_SIZE_CELLS_DEFAULT; } EXPORT_SYMBOL(of_n_size_cells); /* * Find a property with a given name for a given node * and return the value. */ const void *of_get_property(const struct device_node *np, const char *name, int *lenp) { struct property *pp = of_find_property(np, name, lenp); return pp ? pp->value : NULL; } EXPORT_SYMBOL(of_get_property); /** Checks if the given "compat" string matches one of the strings in * the device's "compatible" property */ int of_device_is_compatible(const struct device_node *device, const char *compat) { const char* cp; int cplen, l; cp = of_get_property(device, "compatible", &cplen); if (cp == NULL) return 0; while (cplen > 0) { if (of_compat_cmp(cp, compat, strlen(compat)) == 0) return 1; l = strlen(cp) + 1; cp += l; cplen -= l; } return 0; } EXPORT_SYMBOL(of_device_is_compatible);