| 1 | /* |
| 2 | * Procedures for creating, accessing and interpreting the device tree. |
| 3 | * |
| 4 | * Paul Mackerras August 1996. |
| 5 | * Copyright (C) 1996-2005 Paul Mackerras. |
| 6 | * |
| 7 | * Adapted for 64bit PowerPC by Dave Engebretsen and Peter Bergner. |
| 8 | * {engebret|bergner}@us.ibm.com |
| 9 | * |
| 10 | * Adapted for sparc and sparc64 by David S. Miller davem@davemloft.net |
| 11 | * |
| 12 | * Reconsolidated from arch/x/kernel/prom.c by Stephen Rothwell and |
| 13 | * Grant Likely. |
| 14 | * |
| 15 | * This program is free software; you can redistribute it and/or |
| 16 | * modify it under the terms of the GNU General Public License |
| 17 | * as published by the Free Software Foundation; either version |
| 18 | * 2 of the License, or (at your option) any later version. |
| 19 | */ |
| 20 | #include <linux/ctype.h> |
| 21 | #include <linux/cpu.h> |
| 22 | #include <linux/module.h> |
| 23 | #include <linux/of.h> |
| 24 | #include <linux/spinlock.h> |
| 25 | #include <linux/slab.h> |
| 26 | #include <linux/proc_fs.h> |
| 27 | |
| 28 | #include "of_private.h" |
| 29 | |
| 30 | LIST_HEAD(aliases_lookup); |
| 31 | |
| 32 | struct device_node *of_allnodes; |
| 33 | EXPORT_SYMBOL(of_allnodes); |
| 34 | struct device_node *of_chosen; |
| 35 | struct device_node *of_aliases; |
| 36 | static struct device_node *of_stdout; |
| 37 | |
| 38 | DEFINE_MUTEX(of_aliases_mutex); |
| 39 | |
| 40 | /* use when traversing tree through the allnext, child, sibling, |
| 41 | * or parent members of struct device_node. |
| 42 | */ |
| 43 | DEFINE_RAW_SPINLOCK(devtree_lock); |
| 44 | |
| 45 | int of_n_addr_cells(struct device_node *np) |
| 46 | { |
| 47 | const __be32 *ip; |
| 48 | |
| 49 | do { |
| 50 | if (np->parent) |
| 51 | np = np->parent; |
| 52 | ip = of_get_property(np, "#address-cells", NULL); |
| 53 | if (ip) |
| 54 | return be32_to_cpup(ip); |
| 55 | } while (np->parent); |
| 56 | /* No #address-cells property for the root node */ |
| 57 | return OF_ROOT_NODE_ADDR_CELLS_DEFAULT; |
| 58 | } |
| 59 | EXPORT_SYMBOL(of_n_addr_cells); |
| 60 | |
| 61 | int of_n_size_cells(struct device_node *np) |
| 62 | { |
| 63 | const __be32 *ip; |
| 64 | |
| 65 | do { |
| 66 | if (np->parent) |
| 67 | np = np->parent; |
| 68 | ip = of_get_property(np, "#size-cells", NULL); |
| 69 | if (ip) |
| 70 | return be32_to_cpup(ip); |
| 71 | } while (np->parent); |
| 72 | /* No #size-cells property for the root node */ |
| 73 | return OF_ROOT_NODE_SIZE_CELLS_DEFAULT; |
| 74 | } |
| 75 | EXPORT_SYMBOL(of_n_size_cells); |
| 76 | |
| 77 | #ifdef CONFIG_NUMA |
| 78 | int __weak of_node_to_nid(struct device_node *np) |
| 79 | { |
| 80 | return numa_node_id(); |
| 81 | } |
| 82 | #endif |
| 83 | |
| 84 | #if defined(CONFIG_OF_DYNAMIC) |
| 85 | /** |
| 86 | * of_node_get - Increment refcount of a node |
| 87 | * @node: Node to inc refcount, NULL is supported to |
| 88 | * simplify writing of callers |
| 89 | * |
| 90 | * Returns node. |
| 91 | */ |
| 92 | struct device_node *of_node_get(struct device_node *node) |
| 93 | { |
| 94 | if (node) |
| 95 | kref_get(&node->kref); |
| 96 | return node; |
| 97 | } |
| 98 | EXPORT_SYMBOL(of_node_get); |
| 99 | |
| 100 | static inline struct device_node *kref_to_device_node(struct kref *kref) |
| 101 | { |
| 102 | return container_of(kref, struct device_node, kref); |
| 103 | } |
| 104 | |
| 105 | /** |
| 106 | * of_node_release - release a dynamically allocated node |
| 107 | * @kref: kref element of the node to be released |
| 108 | * |
| 109 | * In of_node_put() this function is passed to kref_put() |
| 110 | * as the destructor. |
| 111 | */ |
| 112 | static void of_node_release(struct kref *kref) |
| 113 | { |
| 114 | struct device_node *node = kref_to_device_node(kref); |
| 115 | struct property *prop = node->properties; |
| 116 | |
| 117 | /* We should never be releasing nodes that haven't been detached. */ |
| 118 | if (!of_node_check_flag(node, OF_DETACHED)) { |
| 119 | pr_err("ERROR: Bad of_node_put() on %s\n", node->full_name); |
| 120 | dump_stack(); |
| 121 | kref_init(&node->kref); |
| 122 | return; |
| 123 | } |
| 124 | |
| 125 | if (!of_node_check_flag(node, OF_DYNAMIC)) |
| 126 | return; |
| 127 | |
| 128 | while (prop) { |
| 129 | struct property *next = prop->next; |
| 130 | kfree(prop->name); |
| 131 | kfree(prop->value); |
| 132 | kfree(prop); |
| 133 | prop = next; |
| 134 | |
| 135 | if (!prop) { |
| 136 | prop = node->deadprops; |
| 137 | node->deadprops = NULL; |
| 138 | } |
| 139 | } |
| 140 | kfree(node->full_name); |
| 141 | kfree(node->data); |
| 142 | kfree(node); |
| 143 | } |
| 144 | |
| 145 | /** |
| 146 | * of_node_put - Decrement refcount of a node |
| 147 | * @node: Node to dec refcount, NULL is supported to |
| 148 | * simplify writing of callers |
| 149 | * |
| 150 | */ |
| 151 | void of_node_put(struct device_node *node) |
| 152 | { |
| 153 | if (node) |
| 154 | kref_put(&node->kref, of_node_release); |
| 155 | } |
| 156 | EXPORT_SYMBOL(of_node_put); |
| 157 | #endif /* CONFIG_OF_DYNAMIC */ |
| 158 | |
| 159 | static struct property *__of_find_property(const struct device_node *np, |
| 160 | const char *name, int *lenp) |
| 161 | { |
| 162 | struct property *pp; |
| 163 | |
| 164 | if (!np) |
| 165 | return NULL; |
| 166 | |
| 167 | for (pp = np->properties; pp; pp = pp->next) { |
| 168 | if (of_prop_cmp(pp->name, name) == 0) { |
| 169 | if (lenp) |
| 170 | *lenp = pp->length; |
| 171 | break; |
| 172 | } |
| 173 | } |
| 174 | |
| 175 | return pp; |
| 176 | } |
| 177 | |
| 178 | struct property *of_find_property(const struct device_node *np, |
| 179 | const char *name, |
| 180 | int *lenp) |
| 181 | { |
| 182 | struct property *pp; |
| 183 | unsigned long flags; |
| 184 | |
| 185 | raw_spin_lock_irqsave(&devtree_lock, flags); |
| 186 | pp = __of_find_property(np, name, lenp); |
| 187 | raw_spin_unlock_irqrestore(&devtree_lock, flags); |
| 188 | |
| 189 | return pp; |
| 190 | } |
| 191 | EXPORT_SYMBOL(of_find_property); |
| 192 | |
| 193 | /** |
| 194 | * of_find_all_nodes - Get next node in global list |
| 195 | * @prev: Previous node or NULL to start iteration |
| 196 | * of_node_put() will be called on it |
| 197 | * |
| 198 | * Returns a node pointer with refcount incremented, use |
| 199 | * of_node_put() on it when done. |
| 200 | */ |
| 201 | struct device_node *of_find_all_nodes(struct device_node *prev) |
| 202 | { |
| 203 | struct device_node *np; |
| 204 | unsigned long flags; |
| 205 | |
| 206 | raw_spin_lock_irqsave(&devtree_lock, flags); |
| 207 | np = prev ? prev->allnext : of_allnodes; |
| 208 | for (; np != NULL; np = np->allnext) |
| 209 | if (of_node_get(np)) |
| 210 | break; |
| 211 | of_node_put(prev); |
| 212 | raw_spin_unlock_irqrestore(&devtree_lock, flags); |
| 213 | return np; |
| 214 | } |
| 215 | EXPORT_SYMBOL(of_find_all_nodes); |
| 216 | |
| 217 | /* |
| 218 | * Find a property with a given name for a given node |
| 219 | * and return the value. |
| 220 | */ |
| 221 | static const void *__of_get_property(const struct device_node *np, |
| 222 | const char *name, int *lenp) |
| 223 | { |
| 224 | struct property *pp = __of_find_property(np, name, lenp); |
| 225 | |
| 226 | return pp ? pp->value : NULL; |
| 227 | } |
| 228 | |
| 229 | /* |
| 230 | * Find a property with a given name for a given node |
| 231 | * and return the value. |
| 232 | */ |
| 233 | const void *of_get_property(const struct device_node *np, const char *name, |
| 234 | int *lenp) |
| 235 | { |
| 236 | struct property *pp = of_find_property(np, name, lenp); |
| 237 | |
| 238 | return pp ? pp->value : NULL; |
| 239 | } |
| 240 | EXPORT_SYMBOL(of_get_property); |
| 241 | |
| 242 | /* |
| 243 | * arch_match_cpu_phys_id - Match the given logical CPU and physical id |
| 244 | * |
| 245 | * @cpu: logical cpu index of a core/thread |
| 246 | * @phys_id: physical identifier of a core/thread |
| 247 | * |
| 248 | * CPU logical to physical index mapping is architecture specific. |
| 249 | * However this __weak function provides a default match of physical |
| 250 | * id to logical cpu index. phys_id provided here is usually values read |
| 251 | * from the device tree which must match the hardware internal registers. |
| 252 | * |
| 253 | * Returns true if the physical identifier and the logical cpu index |
| 254 | * correspond to the same core/thread, false otherwise. |
| 255 | */ |
| 256 | bool __weak arch_match_cpu_phys_id(int cpu, u64 phys_id) |
| 257 | { |
| 258 | return (u32)phys_id == cpu; |
| 259 | } |
| 260 | |
| 261 | /** |
| 262 | * Checks if the given "prop_name" property holds the physical id of the |
| 263 | * core/thread corresponding to the logical cpu 'cpu'. If 'thread' is not |
| 264 | * NULL, local thread number within the core is returned in it. |
| 265 | */ |
| 266 | static bool __of_find_n_match_cpu_property(struct device_node *cpun, |
| 267 | const char *prop_name, int cpu, unsigned int *thread) |
| 268 | { |
| 269 | const __be32 *cell; |
| 270 | int ac, prop_len, tid; |
| 271 | u64 hwid; |
| 272 | |
| 273 | ac = of_n_addr_cells(cpun); |
| 274 | cell = of_get_property(cpun, prop_name, &prop_len); |
| 275 | if (!cell || !ac) |
| 276 | return false; |
| 277 | prop_len /= sizeof(*cell) * ac; |
| 278 | for (tid = 0; tid < prop_len; tid++) { |
| 279 | hwid = of_read_number(cell, ac); |
| 280 | if (arch_match_cpu_phys_id(cpu, hwid)) { |
| 281 | if (thread) |
| 282 | *thread = tid; |
| 283 | return true; |
| 284 | } |
| 285 | cell += ac; |
| 286 | } |
| 287 | return false; |
| 288 | } |
| 289 | |
| 290 | /* |
| 291 | * arch_find_n_match_cpu_physical_id - See if the given device node is |
| 292 | * for the cpu corresponding to logical cpu 'cpu'. Return true if so, |
| 293 | * else false. If 'thread' is non-NULL, the local thread number within the |
| 294 | * core is returned in it. |
| 295 | */ |
| 296 | bool __weak arch_find_n_match_cpu_physical_id(struct device_node *cpun, |
| 297 | int cpu, unsigned int *thread) |
| 298 | { |
| 299 | /* Check for non-standard "ibm,ppc-interrupt-server#s" property |
| 300 | * for thread ids on PowerPC. If it doesn't exist fallback to |
| 301 | * standard "reg" property. |
| 302 | */ |
| 303 | if (IS_ENABLED(CONFIG_PPC) && |
| 304 | __of_find_n_match_cpu_property(cpun, |
| 305 | "ibm,ppc-interrupt-server#s", |
| 306 | cpu, thread)) |
| 307 | return true; |
| 308 | |
| 309 | if (__of_find_n_match_cpu_property(cpun, "reg", cpu, thread)) |
| 310 | return true; |
| 311 | |
| 312 | return false; |
| 313 | } |
| 314 | |
| 315 | /** |
| 316 | * of_get_cpu_node - Get device node associated with the given logical CPU |
| 317 | * |
| 318 | * @cpu: CPU number(logical index) for which device node is required |
| 319 | * @thread: if not NULL, local thread number within the physical core is |
| 320 | * returned |
| 321 | * |
| 322 | * The main purpose of this function is to retrieve the device node for the |
| 323 | * given logical CPU index. It should be used to initialize the of_node in |
| 324 | * cpu device. Once of_node in cpu device is populated, all the further |
| 325 | * references can use that instead. |
| 326 | * |
| 327 | * CPU logical to physical index mapping is architecture specific and is built |
| 328 | * before booting secondary cores. This function uses arch_match_cpu_phys_id |
| 329 | * which can be overridden by architecture specific implementation. |
| 330 | * |
| 331 | * Returns a node pointer for the logical cpu if found, else NULL. |
| 332 | */ |
| 333 | struct device_node *of_get_cpu_node(int cpu, unsigned int *thread) |
| 334 | { |
| 335 | struct device_node *cpun; |
| 336 | |
| 337 | for_each_node_by_type(cpun, "cpu") { |
| 338 | if (arch_find_n_match_cpu_physical_id(cpun, cpu, thread)) |
| 339 | return cpun; |
| 340 | } |
| 341 | return NULL; |
| 342 | } |
| 343 | EXPORT_SYMBOL(of_get_cpu_node); |
| 344 | |
| 345 | /** Checks if the given "compat" string matches one of the strings in |
| 346 | * the device's "compatible" property |
| 347 | */ |
| 348 | static int __of_device_is_compatible(const struct device_node *device, |
| 349 | const char *compat) |
| 350 | { |
| 351 | const char* cp; |
| 352 | int cplen, l; |
| 353 | |
| 354 | cp = __of_get_property(device, "compatible", &cplen); |
| 355 | if (cp == NULL) |
| 356 | return 0; |
| 357 | while (cplen > 0) { |
| 358 | if (of_compat_cmp(cp, compat, strlen(compat)) == 0) |
| 359 | return 1; |
| 360 | l = strlen(cp) + 1; |
| 361 | cp += l; |
| 362 | cplen -= l; |
| 363 | } |
| 364 | |
| 365 | return 0; |
| 366 | } |
| 367 | |
| 368 | /** Checks if the given "compat" string matches one of the strings in |
| 369 | * the device's "compatible" property |
| 370 | */ |
| 371 | int of_device_is_compatible(const struct device_node *device, |
| 372 | const char *compat) |
| 373 | { |
| 374 | unsigned long flags; |
| 375 | int res; |
| 376 | |
| 377 | raw_spin_lock_irqsave(&devtree_lock, flags); |
| 378 | res = __of_device_is_compatible(device, compat); |
| 379 | raw_spin_unlock_irqrestore(&devtree_lock, flags); |
| 380 | return res; |
| 381 | } |
| 382 | EXPORT_SYMBOL(of_device_is_compatible); |
| 383 | |
| 384 | /** |
| 385 | * of_machine_is_compatible - Test root of device tree for a given compatible value |
| 386 | * @compat: compatible string to look for in root node's compatible property. |
| 387 | * |
| 388 | * Returns true if the root node has the given value in its |
| 389 | * compatible property. |
| 390 | */ |
| 391 | int of_machine_is_compatible(const char *compat) |
| 392 | { |
| 393 | struct device_node *root; |
| 394 | int rc = 0; |
| 395 | |
| 396 | root = of_find_node_by_path("/"); |
| 397 | if (root) { |
| 398 | rc = of_device_is_compatible(root, compat); |
| 399 | of_node_put(root); |
| 400 | } |
| 401 | return rc; |
| 402 | } |
| 403 | EXPORT_SYMBOL(of_machine_is_compatible); |
| 404 | |
| 405 | /** |
| 406 | * __of_device_is_available - check if a device is available for use |
| 407 | * |
| 408 | * @device: Node to check for availability, with locks already held |
| 409 | * |
| 410 | * Returns 1 if the status property is absent or set to "okay" or "ok", |
| 411 | * 0 otherwise |
| 412 | */ |
| 413 | static int __of_device_is_available(const struct device_node *device) |
| 414 | { |
| 415 | const char *status; |
| 416 | int statlen; |
| 417 | |
| 418 | status = __of_get_property(device, "status", &statlen); |
| 419 | if (status == NULL) |
| 420 | return 1; |
| 421 | |
| 422 | if (statlen > 0) { |
| 423 | if (!strcmp(status, "okay") || !strcmp(status, "ok")) |
| 424 | return 1; |
| 425 | } |
| 426 | |
| 427 | return 0; |
| 428 | } |
| 429 | |
| 430 | /** |
| 431 | * of_device_is_available - check if a device is available for use |
| 432 | * |
| 433 | * @device: Node to check for availability |
| 434 | * |
| 435 | * Returns 1 if the status property is absent or set to "okay" or "ok", |
| 436 | * 0 otherwise |
| 437 | */ |
| 438 | int of_device_is_available(const struct device_node *device) |
| 439 | { |
| 440 | unsigned long flags; |
| 441 | int res; |
| 442 | |
| 443 | raw_spin_lock_irqsave(&devtree_lock, flags); |
| 444 | res = __of_device_is_available(device); |
| 445 | raw_spin_unlock_irqrestore(&devtree_lock, flags); |
| 446 | return res; |
| 447 | |
| 448 | } |
| 449 | EXPORT_SYMBOL(of_device_is_available); |
| 450 | |
| 451 | /** |
| 452 | * of_get_parent - Get a node's parent if any |
| 453 | * @node: Node to get parent |
| 454 | * |
| 455 | * Returns a node pointer with refcount incremented, use |
| 456 | * of_node_put() on it when done. |
| 457 | */ |
| 458 | struct device_node *of_get_parent(const struct device_node *node) |
| 459 | { |
| 460 | struct device_node *np; |
| 461 | unsigned long flags; |
| 462 | |
| 463 | if (!node) |
| 464 | return NULL; |
| 465 | |
| 466 | raw_spin_lock_irqsave(&devtree_lock, flags); |
| 467 | np = of_node_get(node->parent); |
| 468 | raw_spin_unlock_irqrestore(&devtree_lock, flags); |
| 469 | return np; |
| 470 | } |
| 471 | EXPORT_SYMBOL(of_get_parent); |
| 472 | |
| 473 | /** |
| 474 | * of_get_next_parent - Iterate to a node's parent |
| 475 | * @node: Node to get parent of |
| 476 | * |
| 477 | * This is like of_get_parent() except that it drops the |
| 478 | * refcount on the passed node, making it suitable for iterating |
| 479 | * through a node's parents. |
| 480 | * |
| 481 | * Returns a node pointer with refcount incremented, use |
| 482 | * of_node_put() on it when done. |
| 483 | */ |
| 484 | struct device_node *of_get_next_parent(struct device_node *node) |
| 485 | { |
| 486 | struct device_node *parent; |
| 487 | unsigned long flags; |
| 488 | |
| 489 | if (!node) |
| 490 | return NULL; |
| 491 | |
| 492 | raw_spin_lock_irqsave(&devtree_lock, flags); |
| 493 | parent = of_node_get(node->parent); |
| 494 | of_node_put(node); |
| 495 | raw_spin_unlock_irqrestore(&devtree_lock, flags); |
| 496 | return parent; |
| 497 | } |
| 498 | EXPORT_SYMBOL(of_get_next_parent); |
| 499 | |
| 500 | /** |
| 501 | * of_get_next_child - Iterate a node childs |
| 502 | * @node: parent node |
| 503 | * @prev: previous child of the parent node, or NULL to get first |
| 504 | * |
| 505 | * Returns a node pointer with refcount incremented, use |
| 506 | * of_node_put() on it when done. |
| 507 | */ |
| 508 | struct device_node *of_get_next_child(const struct device_node *node, |
| 509 | struct device_node *prev) |
| 510 | { |
| 511 | struct device_node *next; |
| 512 | unsigned long flags; |
| 513 | |
| 514 | raw_spin_lock_irqsave(&devtree_lock, flags); |
| 515 | next = prev ? prev->sibling : node->child; |
| 516 | for (; next; next = next->sibling) |
| 517 | if (of_node_get(next)) |
| 518 | break; |
| 519 | of_node_put(prev); |
| 520 | raw_spin_unlock_irqrestore(&devtree_lock, flags); |
| 521 | return next; |
| 522 | } |
| 523 | EXPORT_SYMBOL(of_get_next_child); |
| 524 | |
| 525 | /** |
| 526 | * of_get_next_available_child - Find the next available child node |
| 527 | * @node: parent node |
| 528 | * @prev: previous child of the parent node, or NULL to get first |
| 529 | * |
| 530 | * This function is like of_get_next_child(), except that it |
| 531 | * automatically skips any disabled nodes (i.e. status = "disabled"). |
| 532 | */ |
| 533 | struct device_node *of_get_next_available_child(const struct device_node *node, |
| 534 | struct device_node *prev) |
| 535 | { |
| 536 | struct device_node *next; |
| 537 | unsigned long flags; |
| 538 | |
| 539 | raw_spin_lock_irqsave(&devtree_lock, flags); |
| 540 | next = prev ? prev->sibling : node->child; |
| 541 | for (; next; next = next->sibling) { |
| 542 | if (!__of_device_is_available(next)) |
| 543 | continue; |
| 544 | if (of_node_get(next)) |
| 545 | break; |
| 546 | } |
| 547 | of_node_put(prev); |
| 548 | raw_spin_unlock_irqrestore(&devtree_lock, flags); |
| 549 | return next; |
| 550 | } |
| 551 | EXPORT_SYMBOL(of_get_next_available_child); |
| 552 | |
| 553 | /** |
| 554 | * of_get_child_by_name - Find the child node by name for a given parent |
| 555 | * @node: parent node |
| 556 | * @name: child name to look for. |
| 557 | * |
| 558 | * This function looks for child node for given matching name |
| 559 | * |
| 560 | * Returns a node pointer if found, with refcount incremented, use |
| 561 | * of_node_put() on it when done. |
| 562 | * Returns NULL if node is not found. |
| 563 | */ |
| 564 | struct device_node *of_get_child_by_name(const struct device_node *node, |
| 565 | const char *name) |
| 566 | { |
| 567 | struct device_node *child; |
| 568 | |
| 569 | for_each_child_of_node(node, child) |
| 570 | if (child->name && (of_node_cmp(child->name, name) == 0)) |
| 571 | break; |
| 572 | return child; |
| 573 | } |
| 574 | EXPORT_SYMBOL(of_get_child_by_name); |
| 575 | |
| 576 | /** |
| 577 | * of_find_node_by_path - Find a node matching a full OF path |
| 578 | * @path: The full path to match |
| 579 | * |
| 580 | * Returns a node pointer with refcount incremented, use |
| 581 | * of_node_put() on it when done. |
| 582 | */ |
| 583 | struct device_node *of_find_node_by_path(const char *path) |
| 584 | { |
| 585 | struct device_node *np = of_allnodes; |
| 586 | unsigned long flags; |
| 587 | |
| 588 | raw_spin_lock_irqsave(&devtree_lock, flags); |
| 589 | for (; np; np = np->allnext) { |
| 590 | if (np->full_name && (of_node_cmp(np->full_name, path) == 0) |
| 591 | && of_node_get(np)) |
| 592 | break; |
| 593 | } |
| 594 | raw_spin_unlock_irqrestore(&devtree_lock, flags); |
| 595 | return np; |
| 596 | } |
| 597 | EXPORT_SYMBOL(of_find_node_by_path); |
| 598 | |
| 599 | /** |
| 600 | * of_find_node_by_name - Find a node by its "name" property |
| 601 | * @from: The node to start searching from or NULL, the node |
| 602 | * you pass will not be searched, only the next one |
| 603 | * will; typically, you pass what the previous call |
| 604 | * returned. of_node_put() will be called on it |
| 605 | * @name: The name string to match against |
| 606 | * |
| 607 | * Returns a node pointer with refcount incremented, use |
| 608 | * of_node_put() on it when done. |
| 609 | */ |
| 610 | struct device_node *of_find_node_by_name(struct device_node *from, |
| 611 | const char *name) |
| 612 | { |
| 613 | struct device_node *np; |
| 614 | unsigned long flags; |
| 615 | |
| 616 | raw_spin_lock_irqsave(&devtree_lock, flags); |
| 617 | np = from ? from->allnext : of_allnodes; |
| 618 | for (; np; np = np->allnext) |
| 619 | if (np->name && (of_node_cmp(np->name, name) == 0) |
| 620 | && of_node_get(np)) |
| 621 | break; |
| 622 | of_node_put(from); |
| 623 | raw_spin_unlock_irqrestore(&devtree_lock, flags); |
| 624 | return np; |
| 625 | } |
| 626 | EXPORT_SYMBOL(of_find_node_by_name); |
| 627 | |
| 628 | /** |
| 629 | * of_find_node_by_type - Find a node by its "device_type" property |
| 630 | * @from: The node to start searching from, or NULL to start searching |
| 631 | * the entire device tree. The node you pass will not be |
| 632 | * searched, only the next one will; typically, you pass |
| 633 | * what the previous call returned. of_node_put() will be |
| 634 | * called on from for you. |
| 635 | * @type: The type string to match against |
| 636 | * |
| 637 | * Returns a node pointer with refcount incremented, use |
| 638 | * of_node_put() on it when done. |
| 639 | */ |
| 640 | struct device_node *of_find_node_by_type(struct device_node *from, |
| 641 | const char *type) |
| 642 | { |
| 643 | struct device_node *np; |
| 644 | unsigned long flags; |
| 645 | |
| 646 | raw_spin_lock_irqsave(&devtree_lock, flags); |
| 647 | np = from ? from->allnext : of_allnodes; |
| 648 | for (; np; np = np->allnext) |
| 649 | if (np->type && (of_node_cmp(np->type, type) == 0) |
| 650 | && of_node_get(np)) |
| 651 | break; |
| 652 | of_node_put(from); |
| 653 | raw_spin_unlock_irqrestore(&devtree_lock, flags); |
| 654 | return np; |
| 655 | } |
| 656 | EXPORT_SYMBOL(of_find_node_by_type); |
| 657 | |
| 658 | /** |
| 659 | * of_find_compatible_node - Find a node based on type and one of the |
| 660 | * tokens in its "compatible" property |
| 661 | * @from: The node to start searching from or NULL, the node |
| 662 | * you pass will not be searched, only the next one |
| 663 | * will; typically, you pass what the previous call |
| 664 | * returned. of_node_put() will be called on it |
| 665 | * @type: The type string to match "device_type" or NULL to ignore |
| 666 | * @compatible: The string to match to one of the tokens in the device |
| 667 | * "compatible" list. |
| 668 | * |
| 669 | * Returns a node pointer with refcount incremented, use |
| 670 | * of_node_put() on it when done. |
| 671 | */ |
| 672 | struct device_node *of_find_compatible_node(struct device_node *from, |
| 673 | const char *type, const char *compatible) |
| 674 | { |
| 675 | struct device_node *np; |
| 676 | unsigned long flags; |
| 677 | |
| 678 | raw_spin_lock_irqsave(&devtree_lock, flags); |
| 679 | np = from ? from->allnext : of_allnodes; |
| 680 | for (; np; np = np->allnext) { |
| 681 | if (type |
| 682 | && !(np->type && (of_node_cmp(np->type, type) == 0))) |
| 683 | continue; |
| 684 | if (__of_device_is_compatible(np, compatible) && |
| 685 | of_node_get(np)) |
| 686 | break; |
| 687 | } |
| 688 | of_node_put(from); |
| 689 | raw_spin_unlock_irqrestore(&devtree_lock, flags); |
| 690 | return np; |
| 691 | } |
| 692 | EXPORT_SYMBOL(of_find_compatible_node); |
| 693 | |
| 694 | /** |
| 695 | * of_find_node_with_property - Find a node which has a property with |
| 696 | * the given name. |
| 697 | * @from: The node to start searching from or NULL, the node |
| 698 | * you pass will not be searched, only the next one |
| 699 | * will; typically, you pass what the previous call |
| 700 | * returned. of_node_put() will be called on it |
| 701 | * @prop_name: The name of the property to look for. |
| 702 | * |
| 703 | * Returns a node pointer with refcount incremented, use |
| 704 | * of_node_put() on it when done. |
| 705 | */ |
| 706 | struct device_node *of_find_node_with_property(struct device_node *from, |
| 707 | const char *prop_name) |
| 708 | { |
| 709 | struct device_node *np; |
| 710 | struct property *pp; |
| 711 | unsigned long flags; |
| 712 | |
| 713 | raw_spin_lock_irqsave(&devtree_lock, flags); |
| 714 | np = from ? from->allnext : of_allnodes; |
| 715 | for (; np; np = np->allnext) { |
| 716 | for (pp = np->properties; pp; pp = pp->next) { |
| 717 | if (of_prop_cmp(pp->name, prop_name) == 0) { |
| 718 | of_node_get(np); |
| 719 | goto out; |
| 720 | } |
| 721 | } |
| 722 | } |
| 723 | out: |
| 724 | of_node_put(from); |
| 725 | raw_spin_unlock_irqrestore(&devtree_lock, flags); |
| 726 | return np; |
| 727 | } |
| 728 | EXPORT_SYMBOL(of_find_node_with_property); |
| 729 | |
| 730 | static |
| 731 | const struct of_device_id *__of_match_node(const struct of_device_id *matches, |
| 732 | const struct device_node *node) |
| 733 | { |
| 734 | if (!matches) |
| 735 | return NULL; |
| 736 | |
| 737 | while (matches->name[0] || matches->type[0] || matches->compatible[0]) { |
| 738 | int match = 1; |
| 739 | if (matches->name[0]) |
| 740 | match &= node->name |
| 741 | && !strcmp(matches->name, node->name); |
| 742 | if (matches->type[0]) |
| 743 | match &= node->type |
| 744 | && !strcmp(matches->type, node->type); |
| 745 | if (matches->compatible[0]) |
| 746 | match &= __of_device_is_compatible(node, |
| 747 | matches->compatible); |
| 748 | if (match) |
| 749 | return matches; |
| 750 | matches++; |
| 751 | } |
| 752 | return NULL; |
| 753 | } |
| 754 | |
| 755 | /** |
| 756 | * of_match_node - Tell if an device_node has a matching of_match structure |
| 757 | * @matches: array of of device match structures to search in |
| 758 | * @node: the of device structure to match against |
| 759 | * |
| 760 | * Low level utility function used by device matching. |
| 761 | */ |
| 762 | const struct of_device_id *of_match_node(const struct of_device_id *matches, |
| 763 | const struct device_node *node) |
| 764 | { |
| 765 | const struct of_device_id *match; |
| 766 | unsigned long flags; |
| 767 | |
| 768 | raw_spin_lock_irqsave(&devtree_lock, flags); |
| 769 | match = __of_match_node(matches, node); |
| 770 | raw_spin_unlock_irqrestore(&devtree_lock, flags); |
| 771 | return match; |
| 772 | } |
| 773 | EXPORT_SYMBOL(of_match_node); |
| 774 | |
| 775 | /** |
| 776 | * of_find_matching_node_and_match - Find a node based on an of_device_id |
| 777 | * match table. |
| 778 | * @from: The node to start searching from or NULL, the node |
| 779 | * you pass will not be searched, only the next one |
| 780 | * will; typically, you pass what the previous call |
| 781 | * returned. of_node_put() will be called on it |
| 782 | * @matches: array of of device match structures to search in |
| 783 | * @match Updated to point at the matches entry which matched |
| 784 | * |
| 785 | * Returns a node pointer with refcount incremented, use |
| 786 | * of_node_put() on it when done. |
| 787 | */ |
| 788 | struct device_node *of_find_matching_node_and_match(struct device_node *from, |
| 789 | const struct of_device_id *matches, |
| 790 | const struct of_device_id **match) |
| 791 | { |
| 792 | struct device_node *np; |
| 793 | const struct of_device_id *m; |
| 794 | unsigned long flags; |
| 795 | |
| 796 | if (match) |
| 797 | *match = NULL; |
| 798 | |
| 799 | raw_spin_lock_irqsave(&devtree_lock, flags); |
| 800 | np = from ? from->allnext : of_allnodes; |
| 801 | for (; np; np = np->allnext) { |
| 802 | m = __of_match_node(matches, np); |
| 803 | if (m && of_node_get(np)) { |
| 804 | if (match) |
| 805 | *match = m; |
| 806 | break; |
| 807 | } |
| 808 | } |
| 809 | of_node_put(from); |
| 810 | raw_spin_unlock_irqrestore(&devtree_lock, flags); |
| 811 | return np; |
| 812 | } |
| 813 | EXPORT_SYMBOL(of_find_matching_node_and_match); |
| 814 | |
| 815 | /** |
| 816 | * of_modalias_node - Lookup appropriate modalias for a device node |
| 817 | * @node: pointer to a device tree node |
| 818 | * @modalias: Pointer to buffer that modalias value will be copied into |
| 819 | * @len: Length of modalias value |
| 820 | * |
| 821 | * Based on the value of the compatible property, this routine will attempt |
| 822 | * to choose an appropriate modalias value for a particular device tree node. |
| 823 | * It does this by stripping the manufacturer prefix (as delimited by a ',') |
| 824 | * from the first entry in the compatible list property. |
| 825 | * |
| 826 | * This routine returns 0 on success, <0 on failure. |
| 827 | */ |
| 828 | int of_modalias_node(struct device_node *node, char *modalias, int len) |
| 829 | { |
| 830 | const char *compatible, *p; |
| 831 | int cplen; |
| 832 | |
| 833 | compatible = of_get_property(node, "compatible", &cplen); |
| 834 | if (!compatible || strlen(compatible) > cplen) |
| 835 | return -ENODEV; |
| 836 | p = strchr(compatible, ','); |
| 837 | strlcpy(modalias, p ? p + 1 : compatible, len); |
| 838 | return 0; |
| 839 | } |
| 840 | EXPORT_SYMBOL_GPL(of_modalias_node); |
| 841 | |
| 842 | /** |
| 843 | * of_find_node_by_phandle - Find a node given a phandle |
| 844 | * @handle: phandle of the node to find |
| 845 | * |
| 846 | * Returns a node pointer with refcount incremented, use |
| 847 | * of_node_put() on it when done. |
| 848 | */ |
| 849 | struct device_node *of_find_node_by_phandle(phandle handle) |
| 850 | { |
| 851 | struct device_node *np; |
| 852 | unsigned long flags; |
| 853 | |
| 854 | raw_spin_lock_irqsave(&devtree_lock, flags); |
| 855 | for (np = of_allnodes; np; np = np->allnext) |
| 856 | if (np->phandle == handle) |
| 857 | break; |
| 858 | of_node_get(np); |
| 859 | raw_spin_unlock_irqrestore(&devtree_lock, flags); |
| 860 | return np; |
| 861 | } |
| 862 | EXPORT_SYMBOL(of_find_node_by_phandle); |
| 863 | |
| 864 | /** |
| 865 | * of_find_property_value_of_size |
| 866 | * |
| 867 | * @np: device node from which the property value is to be read. |
| 868 | * @propname: name of the property to be searched. |
| 869 | * @len: requested length of property value |
| 870 | * |
| 871 | * Search for a property in a device node and valid the requested size. |
| 872 | * Returns the property value on success, -EINVAL if the property does not |
| 873 | * exist, -ENODATA if property does not have a value, and -EOVERFLOW if the |
| 874 | * property data isn't large enough. |
| 875 | * |
| 876 | */ |
| 877 | static void *of_find_property_value_of_size(const struct device_node *np, |
| 878 | const char *propname, u32 len) |
| 879 | { |
| 880 | struct property *prop = of_find_property(np, propname, NULL); |
| 881 | |
| 882 | if (!prop) |
| 883 | return ERR_PTR(-EINVAL); |
| 884 | if (!prop->value) |
| 885 | return ERR_PTR(-ENODATA); |
| 886 | if (len > prop->length) |
| 887 | return ERR_PTR(-EOVERFLOW); |
| 888 | |
| 889 | return prop->value; |
| 890 | } |
| 891 | |
| 892 | /** |
| 893 | * of_property_read_u32_index - Find and read a u32 from a multi-value property. |
| 894 | * |
| 895 | * @np: device node from which the property value is to be read. |
| 896 | * @propname: name of the property to be searched. |
| 897 | * @index: index of the u32 in the list of values |
| 898 | * @out_value: pointer to return value, modified only if no error. |
| 899 | * |
| 900 | * Search for a property in a device node and read nth 32-bit value from |
| 901 | * it. Returns 0 on success, -EINVAL if the property does not exist, |
| 902 | * -ENODATA if property does not have a value, and -EOVERFLOW if the |
| 903 | * property data isn't large enough. |
| 904 | * |
| 905 | * The out_value is modified only if a valid u32 value can be decoded. |
| 906 | */ |
| 907 | int of_property_read_u32_index(const struct device_node *np, |
| 908 | const char *propname, |
| 909 | u32 index, u32 *out_value) |
| 910 | { |
| 911 | const u32 *val = of_find_property_value_of_size(np, propname, |
| 912 | ((index + 1) * sizeof(*out_value))); |
| 913 | |
| 914 | if (IS_ERR(val)) |
| 915 | return PTR_ERR(val); |
| 916 | |
| 917 | *out_value = be32_to_cpup(((__be32 *)val) + index); |
| 918 | return 0; |
| 919 | } |
| 920 | EXPORT_SYMBOL_GPL(of_property_read_u32_index); |
| 921 | |
| 922 | /** |
| 923 | * of_property_read_u8_array - Find and read an array of u8 from a property. |
| 924 | * |
| 925 | * @np: device node from which the property value is to be read. |
| 926 | * @propname: name of the property to be searched. |
| 927 | * @out_values: pointer to return value, modified only if return value is 0. |
| 928 | * @sz: number of array elements to read |
| 929 | * |
| 930 | * Search for a property in a device node and read 8-bit value(s) from |
| 931 | * it. Returns 0 on success, -EINVAL if the property does not exist, |
| 932 | * -ENODATA if property does not have a value, and -EOVERFLOW if the |
| 933 | * property data isn't large enough. |
| 934 | * |
| 935 | * dts entry of array should be like: |
| 936 | * property = /bits/ 8 <0x50 0x60 0x70>; |
| 937 | * |
| 938 | * The out_values is modified only if a valid u8 value can be decoded. |
| 939 | */ |
| 940 | int of_property_read_u8_array(const struct device_node *np, |
| 941 | const char *propname, u8 *out_values, size_t sz) |
| 942 | { |
| 943 | const u8 *val = of_find_property_value_of_size(np, propname, |
| 944 | (sz * sizeof(*out_values))); |
| 945 | |
| 946 | if (IS_ERR(val)) |
| 947 | return PTR_ERR(val); |
| 948 | |
| 949 | while (sz--) |
| 950 | *out_values++ = *val++; |
| 951 | return 0; |
| 952 | } |
| 953 | EXPORT_SYMBOL_GPL(of_property_read_u8_array); |
| 954 | |
| 955 | /** |
| 956 | * of_property_read_u16_array - Find and read an array of u16 from a property. |
| 957 | * |
| 958 | * @np: device node from which the property value is to be read. |
| 959 | * @propname: name of the property to be searched. |
| 960 | * @out_values: pointer to return value, modified only if return value is 0. |
| 961 | * @sz: number of array elements to read |
| 962 | * |
| 963 | * Search for a property in a device node and read 16-bit value(s) from |
| 964 | * it. Returns 0 on success, -EINVAL if the property does not exist, |
| 965 | * -ENODATA if property does not have a value, and -EOVERFLOW if the |
| 966 | * property data isn't large enough. |
| 967 | * |
| 968 | * dts entry of array should be like: |
| 969 | * property = /bits/ 16 <0x5000 0x6000 0x7000>; |
| 970 | * |
| 971 | * The out_values is modified only if a valid u16 value can be decoded. |
| 972 | */ |
| 973 | int of_property_read_u16_array(const struct device_node *np, |
| 974 | const char *propname, u16 *out_values, size_t sz) |
| 975 | { |
| 976 | const __be16 *val = of_find_property_value_of_size(np, propname, |
| 977 | (sz * sizeof(*out_values))); |
| 978 | |
| 979 | if (IS_ERR(val)) |
| 980 | return PTR_ERR(val); |
| 981 | |
| 982 | while (sz--) |
| 983 | *out_values++ = be16_to_cpup(val++); |
| 984 | return 0; |
| 985 | } |
| 986 | EXPORT_SYMBOL_GPL(of_property_read_u16_array); |
| 987 | |
| 988 | /** |
| 989 | * of_property_read_u32_array - Find and read an array of 32 bit integers |
| 990 | * from a property. |
| 991 | * |
| 992 | * @np: device node from which the property value is to be read. |
| 993 | * @propname: name of the property to be searched. |
| 994 | * @out_values: pointer to return value, modified only if return value is 0. |
| 995 | * @sz: number of array elements to read |
| 996 | * |
| 997 | * Search for a property in a device node and read 32-bit value(s) from |
| 998 | * it. Returns 0 on success, -EINVAL if the property does not exist, |
| 999 | * -ENODATA if property does not have a value, and -EOVERFLOW if the |
| 1000 | * property data isn't large enough. |
| 1001 | * |
| 1002 | * The out_values is modified only if a valid u32 value can be decoded. |
| 1003 | */ |
| 1004 | int of_property_read_u32_array(const struct device_node *np, |
| 1005 | const char *propname, u32 *out_values, |
| 1006 | size_t sz) |
| 1007 | { |
| 1008 | const __be32 *val = of_find_property_value_of_size(np, propname, |
| 1009 | (sz * sizeof(*out_values))); |
| 1010 | |
| 1011 | if (IS_ERR(val)) |
| 1012 | return PTR_ERR(val); |
| 1013 | |
| 1014 | while (sz--) |
| 1015 | *out_values++ = be32_to_cpup(val++); |
| 1016 | return 0; |
| 1017 | } |
| 1018 | EXPORT_SYMBOL_GPL(of_property_read_u32_array); |
| 1019 | |
| 1020 | /** |
| 1021 | * of_property_read_u64 - Find and read a 64 bit integer from a property |
| 1022 | * @np: device node from which the property value is to be read. |
| 1023 | * @propname: name of the property to be searched. |
| 1024 | * @out_value: pointer to return value, modified only if return value is 0. |
| 1025 | * |
| 1026 | * Search for a property in a device node and read a 64-bit value from |
| 1027 | * it. Returns 0 on success, -EINVAL if the property does not exist, |
| 1028 | * -ENODATA if property does not have a value, and -EOVERFLOW if the |
| 1029 | * property data isn't large enough. |
| 1030 | * |
| 1031 | * The out_value is modified only if a valid u64 value can be decoded. |
| 1032 | */ |
| 1033 | int of_property_read_u64(const struct device_node *np, const char *propname, |
| 1034 | u64 *out_value) |
| 1035 | { |
| 1036 | const __be32 *val = of_find_property_value_of_size(np, propname, |
| 1037 | sizeof(*out_value)); |
| 1038 | |
| 1039 | if (IS_ERR(val)) |
| 1040 | return PTR_ERR(val); |
| 1041 | |
| 1042 | *out_value = of_read_number(val, 2); |
| 1043 | return 0; |
| 1044 | } |
| 1045 | EXPORT_SYMBOL_GPL(of_property_read_u64); |
| 1046 | |
| 1047 | /** |
| 1048 | * of_property_read_string - Find and read a string from a property |
| 1049 | * @np: device node from which the property value is to be read. |
| 1050 | * @propname: name of the property to be searched. |
| 1051 | * @out_string: pointer to null terminated return string, modified only if |
| 1052 | * return value is 0. |
| 1053 | * |
| 1054 | * Search for a property in a device tree node and retrieve a null |
| 1055 | * terminated string value (pointer to data, not a copy). Returns 0 on |
| 1056 | * success, -EINVAL if the property does not exist, -ENODATA if property |
| 1057 | * does not have a value, and -EILSEQ if the string is not null-terminated |
| 1058 | * within the length of the property data. |
| 1059 | * |
| 1060 | * The out_string pointer is modified only if a valid string can be decoded. |
| 1061 | */ |
| 1062 | int of_property_read_string(struct device_node *np, const char *propname, |
| 1063 | const char **out_string) |
| 1064 | { |
| 1065 | struct property *prop = of_find_property(np, propname, NULL); |
| 1066 | if (!prop) |
| 1067 | return -EINVAL; |
| 1068 | if (!prop->value) |
| 1069 | return -ENODATA; |
| 1070 | if (strnlen(prop->value, prop->length) >= prop->length) |
| 1071 | return -EILSEQ; |
| 1072 | *out_string = prop->value; |
| 1073 | return 0; |
| 1074 | } |
| 1075 | EXPORT_SYMBOL_GPL(of_property_read_string); |
| 1076 | |
| 1077 | /** |
| 1078 | * of_property_read_string_index - Find and read a string from a multiple |
| 1079 | * strings property. |
| 1080 | * @np: device node from which the property value is to be read. |
| 1081 | * @propname: name of the property to be searched. |
| 1082 | * @index: index of the string in the list of strings |
| 1083 | * @out_string: pointer to null terminated return string, modified only if |
| 1084 | * return value is 0. |
| 1085 | * |
| 1086 | * Search for a property in a device tree node and retrieve a null |
| 1087 | * terminated string value (pointer to data, not a copy) in the list of strings |
| 1088 | * contained in that property. |
| 1089 | * Returns 0 on success, -EINVAL if the property does not exist, -ENODATA if |
| 1090 | * property does not have a value, and -EILSEQ if the string is not |
| 1091 | * null-terminated within the length of the property data. |
| 1092 | * |
| 1093 | * The out_string pointer is modified only if a valid string can be decoded. |
| 1094 | */ |
| 1095 | int of_property_read_string_index(struct device_node *np, const char *propname, |
| 1096 | int index, const char **output) |
| 1097 | { |
| 1098 | struct property *prop = of_find_property(np, propname, NULL); |
| 1099 | int i = 0; |
| 1100 | size_t l = 0, total = 0; |
| 1101 | const char *p; |
| 1102 | |
| 1103 | if (!prop) |
| 1104 | return -EINVAL; |
| 1105 | if (!prop->value) |
| 1106 | return -ENODATA; |
| 1107 | if (strnlen(prop->value, prop->length) >= prop->length) |
| 1108 | return -EILSEQ; |
| 1109 | |
| 1110 | p = prop->value; |
| 1111 | |
| 1112 | for (i = 0; total < prop->length; total += l, p += l) { |
| 1113 | l = strlen(p) + 1; |
| 1114 | if (i++ == index) { |
| 1115 | *output = p; |
| 1116 | return 0; |
| 1117 | } |
| 1118 | } |
| 1119 | return -ENODATA; |
| 1120 | } |
| 1121 | EXPORT_SYMBOL_GPL(of_property_read_string_index); |
| 1122 | |
| 1123 | /** |
| 1124 | * of_property_match_string() - Find string in a list and return index |
| 1125 | * @np: pointer to node containing string list property |
| 1126 | * @propname: string list property name |
| 1127 | * @string: pointer to string to search for in string list |
| 1128 | * |
| 1129 | * This function searches a string list property and returns the index |
| 1130 | * of a specific string value. |
| 1131 | */ |
| 1132 | int of_property_match_string(struct device_node *np, const char *propname, |
| 1133 | const char *string) |
| 1134 | { |
| 1135 | struct property *prop = of_find_property(np, propname, NULL); |
| 1136 | size_t l; |
| 1137 | int i; |
| 1138 | const char *p, *end; |
| 1139 | |
| 1140 | if (!prop) |
| 1141 | return -EINVAL; |
| 1142 | if (!prop->value) |
| 1143 | return -ENODATA; |
| 1144 | |
| 1145 | p = prop->value; |
| 1146 | end = p + prop->length; |
| 1147 | |
| 1148 | for (i = 0; p < end; i++, p += l) { |
| 1149 | l = strlen(p) + 1; |
| 1150 | if (p + l > end) |
| 1151 | return -EILSEQ; |
| 1152 | pr_debug("comparing %s with %s\n", string, p); |
| 1153 | if (strcmp(string, p) == 0) |
| 1154 | return i; /* Found it; return index */ |
| 1155 | } |
| 1156 | return -ENODATA; |
| 1157 | } |
| 1158 | EXPORT_SYMBOL_GPL(of_property_match_string); |
| 1159 | |
| 1160 | /** |
| 1161 | * of_property_count_strings - Find and return the number of strings from a |
| 1162 | * multiple strings property. |
| 1163 | * @np: device node from which the property value is to be read. |
| 1164 | * @propname: name of the property to be searched. |
| 1165 | * |
| 1166 | * Search for a property in a device tree node and retrieve the number of null |
| 1167 | * terminated string contain in it. Returns the number of strings on |
| 1168 | * success, -EINVAL if the property does not exist, -ENODATA if property |
| 1169 | * does not have a value, and -EILSEQ if the string is not null-terminated |
| 1170 | * within the length of the property data. |
| 1171 | */ |
| 1172 | int of_property_count_strings(struct device_node *np, const char *propname) |
| 1173 | { |
| 1174 | struct property *prop = of_find_property(np, propname, NULL); |
| 1175 | int i = 0; |
| 1176 | size_t l = 0, total = 0; |
| 1177 | const char *p; |
| 1178 | |
| 1179 | if (!prop) |
| 1180 | return -EINVAL; |
| 1181 | if (!prop->value) |
| 1182 | return -ENODATA; |
| 1183 | if (strnlen(prop->value, prop->length) >= prop->length) |
| 1184 | return -EILSEQ; |
| 1185 | |
| 1186 | p = prop->value; |
| 1187 | |
| 1188 | for (i = 0; total < prop->length; total += l, p += l, i++) |
| 1189 | l = strlen(p) + 1; |
| 1190 | |
| 1191 | return i; |
| 1192 | } |
| 1193 | EXPORT_SYMBOL_GPL(of_property_count_strings); |
| 1194 | |
| 1195 | void of_print_phandle_args(const char *msg, const struct of_phandle_args *args) |
| 1196 | { |
| 1197 | int i; |
| 1198 | printk("%s %s", msg, of_node_full_name(args->np)); |
| 1199 | for (i = 0; i < args->args_count; i++) |
| 1200 | printk(i ? ",%08x" : ":%08x", args->args[i]); |
| 1201 | printk("\n"); |
| 1202 | } |
| 1203 | |
| 1204 | static int __of_parse_phandle_with_args(const struct device_node *np, |
| 1205 | const char *list_name, |
| 1206 | const char *cells_name, |
| 1207 | int cell_count, int index, |
| 1208 | struct of_phandle_args *out_args) |
| 1209 | { |
| 1210 | const __be32 *list, *list_end; |
| 1211 | int rc = 0, size, cur_index = 0; |
| 1212 | uint32_t count = 0; |
| 1213 | struct device_node *node = NULL; |
| 1214 | phandle phandle; |
| 1215 | |
| 1216 | /* Retrieve the phandle list property */ |
| 1217 | list = of_get_property(np, list_name, &size); |
| 1218 | if (!list) |
| 1219 | return -ENOENT; |
| 1220 | list_end = list + size / sizeof(*list); |
| 1221 | |
| 1222 | /* Loop over the phandles until all the requested entry is found */ |
| 1223 | while (list < list_end) { |
| 1224 | rc = -EINVAL; |
| 1225 | count = 0; |
| 1226 | |
| 1227 | /* |
| 1228 | * If phandle is 0, then it is an empty entry with no |
| 1229 | * arguments. Skip forward to the next entry. |
| 1230 | */ |
| 1231 | phandle = be32_to_cpup(list++); |
| 1232 | if (phandle) { |
| 1233 | /* |
| 1234 | * Find the provider node and parse the #*-cells |
| 1235 | * property to determine the argument length. |
| 1236 | * |
| 1237 | * This is not needed if the cell count is hard-coded |
| 1238 | * (i.e. cells_name not set, but cell_count is set), |
| 1239 | * except when we're going to return the found node |
| 1240 | * below. |
| 1241 | */ |
| 1242 | if (cells_name || cur_index == index) { |
| 1243 | node = of_find_node_by_phandle(phandle); |
| 1244 | if (!node) { |
| 1245 | pr_err("%s: could not find phandle\n", |
| 1246 | np->full_name); |
| 1247 | goto err; |
| 1248 | } |
| 1249 | } |
| 1250 | |
| 1251 | if (cells_name) { |
| 1252 | if (of_property_read_u32(node, cells_name, |
| 1253 | &count)) { |
| 1254 | pr_err("%s: could not get %s for %s\n", |
| 1255 | np->full_name, cells_name, |
| 1256 | node->full_name); |
| 1257 | goto err; |
| 1258 | } |
| 1259 | } else { |
| 1260 | count = cell_count; |
| 1261 | } |
| 1262 | |
| 1263 | /* |
| 1264 | * Make sure that the arguments actually fit in the |
| 1265 | * remaining property data length |
| 1266 | */ |
| 1267 | if (list + count > list_end) { |
| 1268 | pr_err("%s: arguments longer than property\n", |
| 1269 | np->full_name); |
| 1270 | goto err; |
| 1271 | } |
| 1272 | } |
| 1273 | |
| 1274 | /* |
| 1275 | * All of the error cases above bail out of the loop, so at |
| 1276 | * this point, the parsing is successful. If the requested |
| 1277 | * index matches, then fill the out_args structure and return, |
| 1278 | * or return -ENOENT for an empty entry. |
| 1279 | */ |
| 1280 | rc = -ENOENT; |
| 1281 | if (cur_index == index) { |
| 1282 | if (!phandle) |
| 1283 | goto err; |
| 1284 | |
| 1285 | if (out_args) { |
| 1286 | int i; |
| 1287 | if (WARN_ON(count > MAX_PHANDLE_ARGS)) |
| 1288 | count = MAX_PHANDLE_ARGS; |
| 1289 | out_args->np = node; |
| 1290 | out_args->args_count = count; |
| 1291 | for (i = 0; i < count; i++) |
| 1292 | out_args->args[i] = be32_to_cpup(list++); |
| 1293 | } else { |
| 1294 | of_node_put(node); |
| 1295 | } |
| 1296 | |
| 1297 | /* Found it! return success */ |
| 1298 | return 0; |
| 1299 | } |
| 1300 | |
| 1301 | of_node_put(node); |
| 1302 | node = NULL; |
| 1303 | list += count; |
| 1304 | cur_index++; |
| 1305 | } |
| 1306 | |
| 1307 | /* |
| 1308 | * Unlock node before returning result; will be one of: |
| 1309 | * -ENOENT : index is for empty phandle |
| 1310 | * -EINVAL : parsing error on data |
| 1311 | * [1..n] : Number of phandle (count mode; when index = -1) |
| 1312 | */ |
| 1313 | rc = index < 0 ? cur_index : -ENOENT; |
| 1314 | err: |
| 1315 | if (node) |
| 1316 | of_node_put(node); |
| 1317 | return rc; |
| 1318 | } |
| 1319 | |
| 1320 | /** |
| 1321 | * of_parse_phandle - Resolve a phandle property to a device_node pointer |
| 1322 | * @np: Pointer to device node holding phandle property |
| 1323 | * @phandle_name: Name of property holding a phandle value |
| 1324 | * @index: For properties holding a table of phandles, this is the index into |
| 1325 | * the table |
| 1326 | * |
| 1327 | * Returns the device_node pointer with refcount incremented. Use |
| 1328 | * of_node_put() on it when done. |
| 1329 | */ |
| 1330 | struct device_node *of_parse_phandle(const struct device_node *np, |
| 1331 | const char *phandle_name, int index) |
| 1332 | { |
| 1333 | struct of_phandle_args args; |
| 1334 | |
| 1335 | if (index < 0) |
| 1336 | return NULL; |
| 1337 | |
| 1338 | if (__of_parse_phandle_with_args(np, phandle_name, NULL, 0, |
| 1339 | index, &args)) |
| 1340 | return NULL; |
| 1341 | |
| 1342 | return args.np; |
| 1343 | } |
| 1344 | EXPORT_SYMBOL(of_parse_phandle); |
| 1345 | |
| 1346 | /** |
| 1347 | * of_parse_phandle_with_args() - Find a node pointed by phandle in a list |
| 1348 | * @np: pointer to a device tree node containing a list |
| 1349 | * @list_name: property name that contains a list |
| 1350 | * @cells_name: property name that specifies phandles' arguments count |
| 1351 | * @index: index of a phandle to parse out |
| 1352 | * @out_args: optional pointer to output arguments structure (will be filled) |
| 1353 | * |
| 1354 | * This function is useful to parse lists of phandles and their arguments. |
| 1355 | * Returns 0 on success and fills out_args, on error returns appropriate |
| 1356 | * errno value. |
| 1357 | * |
| 1358 | * Caller is responsible to call of_node_put() on the returned out_args->node |
| 1359 | * pointer. |
| 1360 | * |
| 1361 | * Example: |
| 1362 | * |
| 1363 | * phandle1: node1 { |
| 1364 | * #list-cells = <2>; |
| 1365 | * } |
| 1366 | * |
| 1367 | * phandle2: node2 { |
| 1368 | * #list-cells = <1>; |
| 1369 | * } |
| 1370 | * |
| 1371 | * node3 { |
| 1372 | * list = <&phandle1 1 2 &phandle2 3>; |
| 1373 | * } |
| 1374 | * |
| 1375 | * To get a device_node of the `node2' node you may call this: |
| 1376 | * of_parse_phandle_with_args(node3, "list", "#list-cells", 1, &args); |
| 1377 | */ |
| 1378 | int of_parse_phandle_with_args(const struct device_node *np, const char *list_name, |
| 1379 | const char *cells_name, int index, |
| 1380 | struct of_phandle_args *out_args) |
| 1381 | { |
| 1382 | if (index < 0) |
| 1383 | return -EINVAL; |
| 1384 | return __of_parse_phandle_with_args(np, list_name, cells_name, 0, |
| 1385 | index, out_args); |
| 1386 | } |
| 1387 | EXPORT_SYMBOL(of_parse_phandle_with_args); |
| 1388 | |
| 1389 | /** |
| 1390 | * of_parse_phandle_with_fixed_args() - Find a node pointed by phandle in a list |
| 1391 | * @np: pointer to a device tree node containing a list |
| 1392 | * @list_name: property name that contains a list |
| 1393 | * @cell_count: number of argument cells following the phandle |
| 1394 | * @index: index of a phandle to parse out |
| 1395 | * @out_args: optional pointer to output arguments structure (will be filled) |
| 1396 | * |
| 1397 | * This function is useful to parse lists of phandles and their arguments. |
| 1398 | * Returns 0 on success and fills out_args, on error returns appropriate |
| 1399 | * errno value. |
| 1400 | * |
| 1401 | * Caller is responsible to call of_node_put() on the returned out_args->node |
| 1402 | * pointer. |
| 1403 | * |
| 1404 | * Example: |
| 1405 | * |
| 1406 | * phandle1: node1 { |
| 1407 | * } |
| 1408 | * |
| 1409 | * phandle2: node2 { |
| 1410 | * } |
| 1411 | * |
| 1412 | * node3 { |
| 1413 | * list = <&phandle1 0 2 &phandle2 2 3>; |
| 1414 | * } |
| 1415 | * |
| 1416 | * To get a device_node of the `node2' node you may call this: |
| 1417 | * of_parse_phandle_with_fixed_args(node3, "list", 2, 1, &args); |
| 1418 | */ |
| 1419 | int of_parse_phandle_with_fixed_args(const struct device_node *np, |
| 1420 | const char *list_name, int cell_count, |
| 1421 | int index, struct of_phandle_args *out_args) |
| 1422 | { |
| 1423 | if (index < 0) |
| 1424 | return -EINVAL; |
| 1425 | return __of_parse_phandle_with_args(np, list_name, NULL, cell_count, |
| 1426 | index, out_args); |
| 1427 | } |
| 1428 | EXPORT_SYMBOL(of_parse_phandle_with_fixed_args); |
| 1429 | |
| 1430 | /** |
| 1431 | * of_count_phandle_with_args() - Find the number of phandles references in a property |
| 1432 | * @np: pointer to a device tree node containing a list |
| 1433 | * @list_name: property name that contains a list |
| 1434 | * @cells_name: property name that specifies phandles' arguments count |
| 1435 | * |
| 1436 | * Returns the number of phandle + argument tuples within a property. It |
| 1437 | * is a typical pattern to encode a list of phandle and variable |
| 1438 | * arguments into a single property. The number of arguments is encoded |
| 1439 | * by a property in the phandle-target node. For example, a gpios |
| 1440 | * property would contain a list of GPIO specifies consisting of a |
| 1441 | * phandle and 1 or more arguments. The number of arguments are |
| 1442 | * determined by the #gpio-cells property in the node pointed to by the |
| 1443 | * phandle. |
| 1444 | */ |
| 1445 | int of_count_phandle_with_args(const struct device_node *np, const char *list_name, |
| 1446 | const char *cells_name) |
| 1447 | { |
| 1448 | return __of_parse_phandle_with_args(np, list_name, cells_name, 0, -1, |
| 1449 | NULL); |
| 1450 | } |
| 1451 | EXPORT_SYMBOL(of_count_phandle_with_args); |
| 1452 | |
| 1453 | #if defined(CONFIG_OF_DYNAMIC) |
| 1454 | static int of_property_notify(int action, struct device_node *np, |
| 1455 | struct property *prop) |
| 1456 | { |
| 1457 | struct of_prop_reconfig pr; |
| 1458 | |
| 1459 | pr.dn = np; |
| 1460 | pr.prop = prop; |
| 1461 | return of_reconfig_notify(action, &pr); |
| 1462 | } |
| 1463 | #else |
| 1464 | static int of_property_notify(int action, struct device_node *np, |
| 1465 | struct property *prop) |
| 1466 | { |
| 1467 | return 0; |
| 1468 | } |
| 1469 | #endif |
| 1470 | |
| 1471 | /** |
| 1472 | * of_add_property - Add a property to a node |
| 1473 | */ |
| 1474 | int of_add_property(struct device_node *np, struct property *prop) |
| 1475 | { |
| 1476 | struct property **next; |
| 1477 | unsigned long flags; |
| 1478 | int rc; |
| 1479 | |
| 1480 | rc = of_property_notify(OF_RECONFIG_ADD_PROPERTY, np, prop); |
| 1481 | if (rc) |
| 1482 | return rc; |
| 1483 | |
| 1484 | prop->next = NULL; |
| 1485 | raw_spin_lock_irqsave(&devtree_lock, flags); |
| 1486 | next = &np->properties; |
| 1487 | while (*next) { |
| 1488 | if (strcmp(prop->name, (*next)->name) == 0) { |
| 1489 | /* duplicate ! don't insert it */ |
| 1490 | raw_spin_unlock_irqrestore(&devtree_lock, flags); |
| 1491 | return -1; |
| 1492 | } |
| 1493 | next = &(*next)->next; |
| 1494 | } |
| 1495 | *next = prop; |
| 1496 | raw_spin_unlock_irqrestore(&devtree_lock, flags); |
| 1497 | |
| 1498 | #ifdef CONFIG_PROC_DEVICETREE |
| 1499 | /* try to add to proc as well if it was initialized */ |
| 1500 | if (np->pde) |
| 1501 | proc_device_tree_add_prop(np->pde, prop); |
| 1502 | #endif /* CONFIG_PROC_DEVICETREE */ |
| 1503 | |
| 1504 | return 0; |
| 1505 | } |
| 1506 | |
| 1507 | /** |
| 1508 | * of_remove_property - Remove a property from a node. |
| 1509 | * |
| 1510 | * Note that we don't actually remove it, since we have given out |
| 1511 | * who-knows-how-many pointers to the data using get-property. |
| 1512 | * Instead we just move the property to the "dead properties" |
| 1513 | * list, so it won't be found any more. |
| 1514 | */ |
| 1515 | int of_remove_property(struct device_node *np, struct property *prop) |
| 1516 | { |
| 1517 | struct property **next; |
| 1518 | unsigned long flags; |
| 1519 | int found = 0; |
| 1520 | int rc; |
| 1521 | |
| 1522 | rc = of_property_notify(OF_RECONFIG_REMOVE_PROPERTY, np, prop); |
| 1523 | if (rc) |
| 1524 | return rc; |
| 1525 | |
| 1526 | raw_spin_lock_irqsave(&devtree_lock, flags); |
| 1527 | next = &np->properties; |
| 1528 | while (*next) { |
| 1529 | if (*next == prop) { |
| 1530 | /* found the node */ |
| 1531 | *next = prop->next; |
| 1532 | prop->next = np->deadprops; |
| 1533 | np->deadprops = prop; |
| 1534 | found = 1; |
| 1535 | break; |
| 1536 | } |
| 1537 | next = &(*next)->next; |
| 1538 | } |
| 1539 | raw_spin_unlock_irqrestore(&devtree_lock, flags); |
| 1540 | |
| 1541 | if (!found) |
| 1542 | return -ENODEV; |
| 1543 | |
| 1544 | #ifdef CONFIG_PROC_DEVICETREE |
| 1545 | /* try to remove the proc node as well */ |
| 1546 | if (np->pde) |
| 1547 | proc_device_tree_remove_prop(np->pde, prop); |
| 1548 | #endif /* CONFIG_PROC_DEVICETREE */ |
| 1549 | |
| 1550 | return 0; |
| 1551 | } |
| 1552 | |
| 1553 | /* |
| 1554 | * of_update_property - Update a property in a node, if the property does |
| 1555 | * not exist, add it. |
| 1556 | * |
| 1557 | * Note that we don't actually remove it, since we have given out |
| 1558 | * who-knows-how-many pointers to the data using get-property. |
| 1559 | * Instead we just move the property to the "dead properties" list, |
| 1560 | * and add the new property to the property list |
| 1561 | */ |
| 1562 | int of_update_property(struct device_node *np, struct property *newprop) |
| 1563 | { |
| 1564 | struct property **next, *oldprop; |
| 1565 | unsigned long flags; |
| 1566 | int rc, found = 0; |
| 1567 | |
| 1568 | rc = of_property_notify(OF_RECONFIG_UPDATE_PROPERTY, np, newprop); |
| 1569 | if (rc) |
| 1570 | return rc; |
| 1571 | |
| 1572 | if (!newprop->name) |
| 1573 | return -EINVAL; |
| 1574 | |
| 1575 | oldprop = of_find_property(np, newprop->name, NULL); |
| 1576 | if (!oldprop) |
| 1577 | return of_add_property(np, newprop); |
| 1578 | |
| 1579 | raw_spin_lock_irqsave(&devtree_lock, flags); |
| 1580 | next = &np->properties; |
| 1581 | while (*next) { |
| 1582 | if (*next == oldprop) { |
| 1583 | /* found the node */ |
| 1584 | newprop->next = oldprop->next; |
| 1585 | *next = newprop; |
| 1586 | oldprop->next = np->deadprops; |
| 1587 | np->deadprops = oldprop; |
| 1588 | found = 1; |
| 1589 | break; |
| 1590 | } |
| 1591 | next = &(*next)->next; |
| 1592 | } |
| 1593 | raw_spin_unlock_irqrestore(&devtree_lock, flags); |
| 1594 | |
| 1595 | if (!found) |
| 1596 | return -ENODEV; |
| 1597 | |
| 1598 | #ifdef CONFIG_PROC_DEVICETREE |
| 1599 | /* try to add to proc as well if it was initialized */ |
| 1600 | if (np->pde) |
| 1601 | proc_device_tree_update_prop(np->pde, newprop, oldprop); |
| 1602 | #endif /* CONFIG_PROC_DEVICETREE */ |
| 1603 | |
| 1604 | return 0; |
| 1605 | } |
| 1606 | |
| 1607 | #if defined(CONFIG_OF_DYNAMIC) |
| 1608 | /* |
| 1609 | * Support for dynamic device trees. |
| 1610 | * |
| 1611 | * On some platforms, the device tree can be manipulated at runtime. |
| 1612 | * The routines in this section support adding, removing and changing |
| 1613 | * device tree nodes. |
| 1614 | */ |
| 1615 | |
| 1616 | static BLOCKING_NOTIFIER_HEAD(of_reconfig_chain); |
| 1617 | |
| 1618 | int of_reconfig_notifier_register(struct notifier_block *nb) |
| 1619 | { |
| 1620 | return blocking_notifier_chain_register(&of_reconfig_chain, nb); |
| 1621 | } |
| 1622 | EXPORT_SYMBOL_GPL(of_reconfig_notifier_register); |
| 1623 | |
| 1624 | int of_reconfig_notifier_unregister(struct notifier_block *nb) |
| 1625 | { |
| 1626 | return blocking_notifier_chain_unregister(&of_reconfig_chain, nb); |
| 1627 | } |
| 1628 | EXPORT_SYMBOL_GPL(of_reconfig_notifier_unregister); |
| 1629 | |
| 1630 | int of_reconfig_notify(unsigned long action, void *p) |
| 1631 | { |
| 1632 | int rc; |
| 1633 | |
| 1634 | rc = blocking_notifier_call_chain(&of_reconfig_chain, action, p); |
| 1635 | return notifier_to_errno(rc); |
| 1636 | } |
| 1637 | |
| 1638 | #ifdef CONFIG_PROC_DEVICETREE |
| 1639 | static void of_add_proc_dt_entry(struct device_node *dn) |
| 1640 | { |
| 1641 | struct proc_dir_entry *ent; |
| 1642 | |
| 1643 | ent = proc_mkdir(strrchr(dn->full_name, '/') + 1, dn->parent->pde); |
| 1644 | if (ent) |
| 1645 | proc_device_tree_add_node(dn, ent); |
| 1646 | } |
| 1647 | #else |
| 1648 | static void of_add_proc_dt_entry(struct device_node *dn) |
| 1649 | { |
| 1650 | return; |
| 1651 | } |
| 1652 | #endif |
| 1653 | |
| 1654 | /** |
| 1655 | * of_attach_node - Plug a device node into the tree and global list. |
| 1656 | */ |
| 1657 | int of_attach_node(struct device_node *np) |
| 1658 | { |
| 1659 | unsigned long flags; |
| 1660 | int rc; |
| 1661 | |
| 1662 | rc = of_reconfig_notify(OF_RECONFIG_ATTACH_NODE, np); |
| 1663 | if (rc) |
| 1664 | return rc; |
| 1665 | |
| 1666 | raw_spin_lock_irqsave(&devtree_lock, flags); |
| 1667 | np->sibling = np->parent->child; |
| 1668 | np->allnext = of_allnodes; |
| 1669 | np->parent->child = np; |
| 1670 | of_allnodes = np; |
| 1671 | raw_spin_unlock_irqrestore(&devtree_lock, flags); |
| 1672 | |
| 1673 | of_add_proc_dt_entry(np); |
| 1674 | return 0; |
| 1675 | } |
| 1676 | |
| 1677 | #ifdef CONFIG_PROC_DEVICETREE |
| 1678 | static void of_remove_proc_dt_entry(struct device_node *dn) |
| 1679 | { |
| 1680 | proc_remove(dn->pde); |
| 1681 | } |
| 1682 | #else |
| 1683 | static void of_remove_proc_dt_entry(struct device_node *dn) |
| 1684 | { |
| 1685 | return; |
| 1686 | } |
| 1687 | #endif |
| 1688 | |
| 1689 | /** |
| 1690 | * of_detach_node - "Unplug" a node from the device tree. |
| 1691 | * |
| 1692 | * The caller must hold a reference to the node. The memory associated with |
| 1693 | * the node is not freed until its refcount goes to zero. |
| 1694 | */ |
| 1695 | int of_detach_node(struct device_node *np) |
| 1696 | { |
| 1697 | struct device_node *parent; |
| 1698 | unsigned long flags; |
| 1699 | int rc = 0; |
| 1700 | |
| 1701 | rc = of_reconfig_notify(OF_RECONFIG_DETACH_NODE, np); |
| 1702 | if (rc) |
| 1703 | return rc; |
| 1704 | |
| 1705 | raw_spin_lock_irqsave(&devtree_lock, flags); |
| 1706 | |
| 1707 | if (of_node_check_flag(np, OF_DETACHED)) { |
| 1708 | /* someone already detached it */ |
| 1709 | raw_spin_unlock_irqrestore(&devtree_lock, flags); |
| 1710 | return rc; |
| 1711 | } |
| 1712 | |
| 1713 | parent = np->parent; |
| 1714 | if (!parent) { |
| 1715 | raw_spin_unlock_irqrestore(&devtree_lock, flags); |
| 1716 | return rc; |
| 1717 | } |
| 1718 | |
| 1719 | if (of_allnodes == np) |
| 1720 | of_allnodes = np->allnext; |
| 1721 | else { |
| 1722 | struct device_node *prev; |
| 1723 | for (prev = of_allnodes; |
| 1724 | prev->allnext != np; |
| 1725 | prev = prev->allnext) |
| 1726 | ; |
| 1727 | prev->allnext = np->allnext; |
| 1728 | } |
| 1729 | |
| 1730 | if (parent->child == np) |
| 1731 | parent->child = np->sibling; |
| 1732 | else { |
| 1733 | struct device_node *prevsib; |
| 1734 | for (prevsib = np->parent->child; |
| 1735 | prevsib->sibling != np; |
| 1736 | prevsib = prevsib->sibling) |
| 1737 | ; |
| 1738 | prevsib->sibling = np->sibling; |
| 1739 | } |
| 1740 | |
| 1741 | of_node_set_flag(np, OF_DETACHED); |
| 1742 | raw_spin_unlock_irqrestore(&devtree_lock, flags); |
| 1743 | |
| 1744 | of_remove_proc_dt_entry(np); |
| 1745 | return rc; |
| 1746 | } |
| 1747 | #endif /* defined(CONFIG_OF_DYNAMIC) */ |
| 1748 | |
| 1749 | static void of_alias_add(struct alias_prop *ap, struct device_node *np, |
| 1750 | int id, const char *stem, int stem_len) |
| 1751 | { |
| 1752 | ap->np = np; |
| 1753 | ap->id = id; |
| 1754 | strncpy(ap->stem, stem, stem_len); |
| 1755 | ap->stem[stem_len] = 0; |
| 1756 | list_add_tail(&ap->link, &aliases_lookup); |
| 1757 | pr_debug("adding DT alias:%s: stem=%s id=%i node=%s\n", |
| 1758 | ap->alias, ap->stem, ap->id, of_node_full_name(np)); |
| 1759 | } |
| 1760 | |
| 1761 | /** |
| 1762 | * of_alias_scan - Scan all properties of 'aliases' node |
| 1763 | * |
| 1764 | * The function scans all the properties of 'aliases' node and populate |
| 1765 | * the the global lookup table with the properties. It returns the |
| 1766 | * number of alias_prop found, or error code in error case. |
| 1767 | * |
| 1768 | * @dt_alloc: An allocator that provides a virtual address to memory |
| 1769 | * for the resulting tree |
| 1770 | */ |
| 1771 | void of_alias_scan(void * (*dt_alloc)(u64 size, u64 align)) |
| 1772 | { |
| 1773 | struct property *pp; |
| 1774 | |
| 1775 | of_chosen = of_find_node_by_path("/chosen"); |
| 1776 | if (of_chosen == NULL) |
| 1777 | of_chosen = of_find_node_by_path("/chosen@0"); |
| 1778 | |
| 1779 | if (of_chosen) { |
| 1780 | const char *name; |
| 1781 | |
| 1782 | name = of_get_property(of_chosen, "linux,stdout-path", NULL); |
| 1783 | if (name) |
| 1784 | of_stdout = of_find_node_by_path(name); |
| 1785 | } |
| 1786 | |
| 1787 | of_aliases = of_find_node_by_path("/aliases"); |
| 1788 | if (!of_aliases) |
| 1789 | return; |
| 1790 | |
| 1791 | for_each_property_of_node(of_aliases, pp) { |
| 1792 | const char *start = pp->name; |
| 1793 | const char *end = start + strlen(start); |
| 1794 | struct device_node *np; |
| 1795 | struct alias_prop *ap; |
| 1796 | int id, len; |
| 1797 | |
| 1798 | /* Skip those we do not want to proceed */ |
| 1799 | if (!strcmp(pp->name, "name") || |
| 1800 | !strcmp(pp->name, "phandle") || |
| 1801 | !strcmp(pp->name, "linux,phandle")) |
| 1802 | continue; |
| 1803 | |
| 1804 | np = of_find_node_by_path(pp->value); |
| 1805 | if (!np) |
| 1806 | continue; |
| 1807 | |
| 1808 | /* walk the alias backwards to extract the id and work out |
| 1809 | * the 'stem' string */ |
| 1810 | while (isdigit(*(end-1)) && end > start) |
| 1811 | end--; |
| 1812 | len = end - start; |
| 1813 | |
| 1814 | if (kstrtoint(end, 10, &id) < 0) |
| 1815 | continue; |
| 1816 | |
| 1817 | /* Allocate an alias_prop with enough space for the stem */ |
| 1818 | ap = dt_alloc(sizeof(*ap) + len + 1, 4); |
| 1819 | if (!ap) |
| 1820 | continue; |
| 1821 | memset(ap, 0, sizeof(*ap) + len + 1); |
| 1822 | ap->alias = start; |
| 1823 | of_alias_add(ap, np, id, start, len); |
| 1824 | } |
| 1825 | } |
| 1826 | |
| 1827 | /** |
| 1828 | * of_alias_get_id - Get alias id for the given device_node |
| 1829 | * @np: Pointer to the given device_node |
| 1830 | * @stem: Alias stem of the given device_node |
| 1831 | * |
| 1832 | * The function travels the lookup table to get alias id for the given |
| 1833 | * device_node and alias stem. It returns the alias id if find it. |
| 1834 | */ |
| 1835 | int of_alias_get_id(struct device_node *np, const char *stem) |
| 1836 | { |
| 1837 | struct alias_prop *app; |
| 1838 | int id = -ENODEV; |
| 1839 | |
| 1840 | mutex_lock(&of_aliases_mutex); |
| 1841 | list_for_each_entry(app, &aliases_lookup, link) { |
| 1842 | if (strcmp(app->stem, stem) != 0) |
| 1843 | continue; |
| 1844 | |
| 1845 | if (np == app->np) { |
| 1846 | id = app->id; |
| 1847 | break; |
| 1848 | } |
| 1849 | } |
| 1850 | mutex_unlock(&of_aliases_mutex); |
| 1851 | |
| 1852 | return id; |
| 1853 | } |
| 1854 | EXPORT_SYMBOL_GPL(of_alias_get_id); |
| 1855 | |
| 1856 | const __be32 *of_prop_next_u32(struct property *prop, const __be32 *cur, |
| 1857 | u32 *pu) |
| 1858 | { |
| 1859 | const void *curv = cur; |
| 1860 | |
| 1861 | if (!prop) |
| 1862 | return NULL; |
| 1863 | |
| 1864 | if (!cur) { |
| 1865 | curv = prop->value; |
| 1866 | goto out_val; |
| 1867 | } |
| 1868 | |
| 1869 | curv += sizeof(*cur); |
| 1870 | if (curv >= prop->value + prop->length) |
| 1871 | return NULL; |
| 1872 | |
| 1873 | out_val: |
| 1874 | *pu = be32_to_cpup(curv); |
| 1875 | return curv; |
| 1876 | } |
| 1877 | EXPORT_SYMBOL_GPL(of_prop_next_u32); |
| 1878 | |
| 1879 | const char *of_prop_next_string(struct property *prop, const char *cur) |
| 1880 | { |
| 1881 | const void *curv = cur; |
| 1882 | |
| 1883 | if (!prop) |
| 1884 | return NULL; |
| 1885 | |
| 1886 | if (!cur) |
| 1887 | return prop->value; |
| 1888 | |
| 1889 | curv += strlen(cur) + 1; |
| 1890 | if (curv >= prop->value + prop->length) |
| 1891 | return NULL; |
| 1892 | |
| 1893 | return curv; |
| 1894 | } |
| 1895 | EXPORT_SYMBOL_GPL(of_prop_next_string); |
| 1896 | |
| 1897 | /** |
| 1898 | * of_device_is_stdout_path - check if a device node matches the |
| 1899 | * linux,stdout-path property |
| 1900 | * |
| 1901 | * Check if this device node matches the linux,stdout-path property |
| 1902 | * in the chosen node. return true if yes, false otherwise. |
| 1903 | */ |
| 1904 | int of_device_is_stdout_path(struct device_node *dn) |
| 1905 | { |
| 1906 | if (!of_stdout) |
| 1907 | return false; |
| 1908 | |
| 1909 | return of_stdout == dn; |
| 1910 | } |
| 1911 | EXPORT_SYMBOL_GPL(of_device_is_stdout_path); |
| 1912 | |
| 1913 | /** |
| 1914 | * of_find_next_cache_node - Find a node's subsidiary cache |
| 1915 | * @np: node of type "cpu" or "cache" |
| 1916 | * |
| 1917 | * Returns a node pointer with refcount incremented, use |
| 1918 | * of_node_put() on it when done. Caller should hold a reference |
| 1919 | * to np. |
| 1920 | */ |
| 1921 | struct device_node *of_find_next_cache_node(const struct device_node *np) |
| 1922 | { |
| 1923 | struct device_node *child; |
| 1924 | const phandle *handle; |
| 1925 | |
| 1926 | handle = of_get_property(np, "l2-cache", NULL); |
| 1927 | if (!handle) |
| 1928 | handle = of_get_property(np, "next-level-cache", NULL); |
| 1929 | |
| 1930 | if (handle) |
| 1931 | return of_find_node_by_phandle(be32_to_cpup(handle)); |
| 1932 | |
| 1933 | /* OF on pmac has nodes instead of properties named "l2-cache" |
| 1934 | * beneath CPU nodes. |
| 1935 | */ |
| 1936 | if (!strcmp(np->type, "cpu")) |
| 1937 | for_each_child_of_node(np, child) |
| 1938 | if (!strcmp(child->type, "cache")) |
| 1939 | return child; |
| 1940 | |
| 1941 | return NULL; |
| 1942 | } |