/* * Copyright (c) 2011 The Chromium OS Authors. All rights reserved. * * 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. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, * MA 02111-1307 USA */ #include <assert.h> #include <ctype.h> #include <getopt.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include <libfdt.h> #include "util.h" /* These are the operations we support */ enum oper_type { OPER_WRITE_PROP, /* Write a property in a node */ OPER_CREATE_NODE, /* Create a new node */ }; struct display_info { enum oper_type oper; /* operation to perform */ int type; /* data type (s/i/u/x or 0 for default) */ int size; /* data size (1/2/4) */ int verbose; /* verbose output */ int auto_path; /* automatically create all path components */ }; /** * Report an error with a particular node. * * @param name Node name to report error on * @param namelen Length of node name, or -1 to use entire string * @param err Error number to report (-FDT_ERR_...) */ static void report_error(const char *name, int namelen, int err) { if (namelen == -1) namelen = strlen(name); fprintf(stderr, "Error at '%1.*s': %s\n", namelen, name, fdt_strerror(err)); } /** * Encode a series of arguments in a property value. * * @param disp Display information / options * @param arg List of arguments from command line * @param arg_count Number of arguments (may be 0) * @param valuep Returns buffer containing value * @param *value_len Returns length of value encoded */ static int encode_value(struct display_info *disp, char **arg, int arg_count, char **valuep, int *value_len) { char *value = NULL; /* holding area for value */ int value_size = 0; /* size of holding area */ char *ptr; /* pointer to current value position */ int len; /* length of this cell/string/byte */ int ival; int upto; /* the number of bytes we have written to buf */ char fmt[3]; upto = 0; if (disp->verbose) fprintf(stderr, "Decoding value:\n"); fmt[0] = '%'; fmt[1] = disp->type ? disp->type : 'd'; fmt[2] = '\0'; for (; arg_count > 0; arg++, arg_count--, upto += len) { /* assume integer unless told otherwise */ if (disp->type == 's') len = strlen(*arg) + 1; else len = disp->size == -1 ? 4 : disp->size; /* enlarge our value buffer by a suitable margin if needed */ if (upto + len > value_size) { value_size = (upto + len) + 500; value = realloc(value, value_size); if (!value) { fprintf(stderr, "Out of mmory: cannot alloc " "%d bytes\n", value_size); return -1; } } ptr = value + upto; if (disp->type == 's') { memcpy(ptr, *arg, len); if (disp->verbose) fprintf(stderr, "\tstring: '%s'\n", ptr); } else { int *iptr = (int *)ptr; sscanf(*arg, fmt, &ival); if (len == 4) *iptr = cpu_to_fdt32(ival); else *ptr = (uint8_t)ival; if (disp->verbose) { fprintf(stderr, "\t%s: %d\n", disp->size == 1 ? "byte" : disp->size == 2 ? "short" : "int", ival); } } } *value_len = upto; *valuep = value; if (disp->verbose) fprintf(stderr, "Value size %d\n", upto); return 0; } static int store_key_value(void *blob, const char *node_name, const char *property, const char *buf, int len) { int node; int err; node = fdt_path_offset(blob, node_name); if (node < 0) { report_error(node_name, -1, node); return -1; } err = fdt_setprop(blob, node, property, buf, len); if (err) { report_error(property, -1, err); return -1; } return 0; } /** * Create paths as needed for all components of a path * * Any components of the path that do not exist are created. Errors are * reported. * * @param blob FDT blob to write into * @param in_path Path to process * @return 0 if ok, -1 on error */ static int create_paths(void *blob, const char *in_path) { const char *path = in_path; const char *sep; int node, offset = 0; /* skip leading '/' */ while (*path == '/') path++; for (sep = path; *sep; path = sep + 1, offset = node) { /* equivalent to strchrnul(), but it requires _GNU_SOURCE */ sep = strchr(path, '/'); if (!sep) sep = path + strlen(path); node = fdt_subnode_offset_namelen(blob, offset, path, sep - path); if (node == -FDT_ERR_NOTFOUND) { node = fdt_add_subnode_namelen(blob, offset, path, sep - path); } if (node < 0) { report_error(path, sep - path, node); return -1; } } return 0; } /** * Create a new node in the fdt. * * This will overwrite the node_name string. Any error is reported. * * TODO: Perhaps create fdt_path_offset_namelen() so we don't need to do this. * * @param blob FDT blob to write into * @param node_name Name of node to create * @return new node offset if found, or -1 on failure */ static int create_node(void *blob, const char *node_name) { int node = 0; char *p; p = strrchr(node_name, '/'); if (!p) { report_error(node_name, -1, -FDT_ERR_BADPATH); return -1; } *p = '\0'; if (p > node_name) { node = fdt_path_offset(blob, node_name); if (node < 0) { report_error(node_name, -1, node); return -1; } } node = fdt_add_subnode(blob, node, p + 1); if (node < 0) { report_error(p + 1, -1, node); return -1; } return 0; } static int do_fdtput(struct display_info *disp, const char *filename, char **arg, int arg_count) { char *value; char *blob; int len, ret = 0; blob = utilfdt_read(filename); if (!blob) return -1; switch (disp->oper) { case OPER_WRITE_PROP: /* * Convert the arguments into a single binary value, then * store them into the property. */ assert(arg_count >= 2); if (disp->auto_path && create_paths(blob, *arg)) return -1; if (encode_value(disp, arg + 2, arg_count - 2, &value, &len) || store_key_value(blob, *arg, arg[1], value, len)) ret = -1; break; case OPER_CREATE_NODE: for (; ret >= 0 && arg_count--; arg++) { if (disp->auto_path) ret = create_paths(blob, *arg); else ret = create_node(blob, *arg); } break; } if (ret >= 0) ret = utilfdt_write(filename, blob); free(blob); return ret; } static const char *usage_msg = "fdtput - write a property value to a device tree\n" "\n" "The command line arguments are joined together into a single value.\n" "\n" "Usage:\n" " fdtput <options> <dt file> <node> <property> [<value>...]\n" " fdtput -c <options> <dt file> [<node>...]\n" "Options:\n" "\t-c\t\tCreate nodes if they don't already exist\n" "\t-p\t\tAutomatically create nodes as needed for the node path\n" "\t-t <type>\tType of data\n" "\t-v\t\tVerbose: display each value decoded from command line\n" "\t-h\t\tPrint this help\n\n" USAGE_TYPE_MSG; static void usage(const char *msg) { if (msg) fprintf(stderr, "Error: %s\n\n", msg); fprintf(stderr, "%s", usage_msg); exit(2); } int main(int argc, char *argv[]) { struct display_info disp; char *filename = NULL; memset(&disp, '\0', sizeof(disp)); disp.size = -1; disp.oper = OPER_WRITE_PROP; for (;;) { int c = getopt(argc, argv, "chpt:v"); if (c == -1) break; /* * TODO: add options to: * - delete property * - delete node (optionally recursively) * - rename node * - pack fdt before writing * - set amount of free space when writing * - expand fdt if value doesn't fit */ switch (c) { case 'c': disp.oper = OPER_CREATE_NODE; break; case 'h': case '?': usage(NULL); case 'p': disp.auto_path = 1; break; case 't': if (utilfdt_decode_type(optarg, &disp.type, &disp.size)) usage("Invalid type string"); break; case 'v': disp.verbose = 1; break; } } if (optind < argc) filename = argv[optind++]; if (!filename) usage("Missing filename"); argv += optind; argc -= optind; if (disp.oper == OPER_WRITE_PROP) { if (argc < 1) usage("Missing node"); if (argc < 2) usage("Missing property"); } if (do_fdtput(&disp, filename, argv, argc)) return 1; return 0; }