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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/console.h> | |
21 | #include <linux/ctype.h> | |
22 | #include <linux/cpu.h> | |
23 | #include <linux/module.h> | |
24 | #include <linux/of.h> | |
25 | #include <linux/of_graph.h> | |
26 | #include <linux/spinlock.h> | |
27 | #include <linux/slab.h> | |
28 | #include <linux/string.h> | |
29 | #include <linux/proc_fs.h> | |
30 | ||
31 | #include "of_private.h" | |
32 | ||
33 | LIST_HEAD(aliases_lookup); | |
34 | ||
35 | struct device_node *of_root; | |
36 | EXPORT_SYMBOL(of_root); | |
37 | struct device_node *of_chosen; | |
38 | struct device_node *of_aliases; | |
39 | struct device_node *of_stdout; | |
40 | ||
41 | struct kset *of_kset; | |
42 | ||
43 | /* | |
44 | * Used to protect the of_aliases, to hold off addition of nodes to sysfs. | |
45 | * This mutex must be held whenever modifications are being made to the | |
46 | * device tree. The of_{attach,detach}_node() and | |
47 | * of_{add,remove,update}_property() helpers make sure this happens. | |
48 | */ | |
49 | DEFINE_MUTEX(of_mutex); | |
50 | ||
51 | /* use when traversing tree through the child, sibling, | |
52 | * or parent members of struct device_node. | |
53 | */ | |
54 | DEFINE_RAW_SPINLOCK(devtree_lock); | |
55 | ||
56 | int of_n_addr_cells(struct device_node *np) | |
57 | { | |
58 | const __be32 *ip; | |
59 | ||
60 | do { | |
61 | if (np->parent) | |
62 | np = np->parent; | |
63 | ip = of_get_property(np, "#address-cells", NULL); | |
64 | if (ip) | |
65 | return be32_to_cpup(ip); | |
66 | } while (np->parent); | |
67 | /* No #address-cells property for the root node */ | |
68 | return OF_ROOT_NODE_ADDR_CELLS_DEFAULT; | |
69 | } | |
70 | EXPORT_SYMBOL(of_n_addr_cells); | |
71 | ||
72 | int of_n_size_cells(struct device_node *np) | |
73 | { | |
74 | const __be32 *ip; | |
75 | ||
76 | do { | |
77 | if (np->parent) | |
78 | np = np->parent; | |
79 | ip = of_get_property(np, "#size-cells", NULL); | |
80 | if (ip) | |
81 | return be32_to_cpup(ip); | |
82 | } while (np->parent); | |
83 | /* No #size-cells property for the root node */ | |
84 | return OF_ROOT_NODE_SIZE_CELLS_DEFAULT; | |
85 | } | |
86 | EXPORT_SYMBOL(of_n_size_cells); | |
87 | ||
88 | #ifdef CONFIG_NUMA | |
89 | int __weak of_node_to_nid(struct device_node *np) | |
90 | { | |
91 | return numa_node_id(); | |
92 | } | |
93 | #endif | |
94 | ||
95 | #ifndef CONFIG_OF_DYNAMIC | |
96 | static void of_node_release(struct kobject *kobj) | |
97 | { | |
98 | /* Without CONFIG_OF_DYNAMIC, no nodes gets freed */ | |
99 | } | |
100 | #endif /* CONFIG_OF_DYNAMIC */ | |
101 | ||
102 | struct kobj_type of_node_ktype = { | |
103 | .release = of_node_release, | |
104 | }; | |
105 | ||
106 | static ssize_t of_node_property_read(struct file *filp, struct kobject *kobj, | |
107 | struct bin_attribute *bin_attr, char *buf, | |
108 | loff_t offset, size_t count) | |
109 | { | |
110 | struct property *pp = container_of(bin_attr, struct property, attr); | |
111 | return memory_read_from_buffer(buf, count, &offset, pp->value, pp->length); | |
112 | } | |
113 | ||
114 | static const char *safe_name(struct kobject *kobj, const char *orig_name) | |
115 | { | |
116 | const char *name = orig_name; | |
117 | struct kernfs_node *kn; | |
118 | int i = 0; | |
119 | ||
120 | /* don't be a hero. After 16 tries give up */ | |
121 | while (i < 16 && (kn = sysfs_get_dirent(kobj->sd, name))) { | |
122 | sysfs_put(kn); | |
123 | if (name != orig_name) | |
124 | kfree(name); | |
125 | name = kasprintf(GFP_KERNEL, "%s#%i", orig_name, ++i); | |
126 | } | |
127 | ||
128 | if (name != orig_name) | |
129 | pr_warn("device-tree: Duplicate name in %s, renamed to \"%s\"\n", | |
130 | kobject_name(kobj), name); | |
131 | return name; | |
132 | } | |
133 | ||
134 | int __of_add_property_sysfs(struct device_node *np, struct property *pp) | |
135 | { | |
136 | int rc; | |
137 | ||
138 | /* Important: Don't leak passwords */ | |
139 | bool secure = strncmp(pp->name, "security-", 9) == 0; | |
140 | ||
141 | if (!IS_ENABLED(CONFIG_SYSFS)) | |
142 | return 0; | |
143 | ||
144 | if (!of_kset || !of_node_is_attached(np)) | |
145 | return 0; | |
146 | ||
147 | sysfs_bin_attr_init(&pp->attr); | |
148 | pp->attr.attr.name = safe_name(&np->kobj, pp->name); | |
149 | pp->attr.attr.mode = secure ? S_IRUSR : S_IRUGO; | |
150 | pp->attr.size = secure ? 0 : pp->length; | |
151 | pp->attr.read = of_node_property_read; | |
152 | ||
153 | rc = sysfs_create_bin_file(&np->kobj, &pp->attr); | |
154 | WARN(rc, "error adding attribute %s to node %s\n", pp->name, np->full_name); | |
155 | return rc; | |
156 | } | |
157 | ||
158 | int __of_attach_node_sysfs(struct device_node *np) | |
159 | { | |
160 | const char *name; | |
161 | struct property *pp; | |
162 | int rc; | |
163 | ||
164 | if (!IS_ENABLED(CONFIG_SYSFS)) | |
165 | return 0; | |
166 | ||
167 | if (!of_kset) | |
168 | return 0; | |
169 | ||
170 | np->kobj.kset = of_kset; | |
171 | if (!np->parent) { | |
172 | /* Nodes without parents are new top level trees */ | |
173 | rc = kobject_add(&np->kobj, NULL, "%s", | |
174 | safe_name(&of_kset->kobj, "base")); | |
175 | } else { | |
176 | name = safe_name(&np->parent->kobj, kbasename(np->full_name)); | |
177 | if (!name || !name[0]) | |
178 | return -EINVAL; | |
179 | ||
180 | rc = kobject_add(&np->kobj, &np->parent->kobj, "%s", name); | |
181 | } | |
182 | if (rc) | |
183 | return rc; | |
184 | ||
185 | for_each_property_of_node(np, pp) | |
186 | __of_add_property_sysfs(np, pp); | |
187 | ||
188 | return 0; | |
189 | } | |
190 | ||
191 | static int __init of_init(void) | |
192 | { | |
193 | struct device_node *np; | |
194 | ||
195 | /* Create the kset, and register existing nodes */ | |
196 | mutex_lock(&of_mutex); | |
197 | of_kset = kset_create_and_add("devicetree", NULL, firmware_kobj); | |
198 | if (!of_kset) { | |
199 | mutex_unlock(&of_mutex); | |
200 | return -ENOMEM; | |
201 | } | |
202 | for_each_of_allnodes(np) | |
203 | __of_attach_node_sysfs(np); | |
204 | mutex_unlock(&of_mutex); | |
205 | ||
206 | /* Symlink in /proc as required by userspace ABI */ | |
207 | if (of_root) | |
208 | proc_symlink("device-tree", NULL, "/sys/firmware/devicetree/base"); | |
209 | ||
210 | return 0; | |
211 | } | |
212 | core_initcall(of_init); | |
213 | ||
214 | static struct property *__of_find_property(const struct device_node *np, | |
215 | const char *name, int *lenp) | |
216 | { | |
217 | struct property *pp; | |
218 | ||
219 | if (!np) | |
220 | return NULL; | |
221 | ||
222 | for (pp = np->properties; pp; pp = pp->next) { | |
223 | if (of_prop_cmp(pp->name, name) == 0) { | |
224 | if (lenp) | |
225 | *lenp = pp->length; | |
226 | break; | |
227 | } | |
228 | } | |
229 | ||
230 | return pp; | |
231 | } | |
232 | ||
233 | struct property *of_find_property(const struct device_node *np, | |
234 | const char *name, | |
235 | int *lenp) | |
236 | { | |
237 | struct property *pp; | |
238 | unsigned long flags; | |
239 | ||
240 | raw_spin_lock_irqsave(&devtree_lock, flags); | |
241 | pp = __of_find_property(np, name, lenp); | |
242 | raw_spin_unlock_irqrestore(&devtree_lock, flags); | |
243 | ||
244 | return pp; | |
245 | } | |
246 | EXPORT_SYMBOL(of_find_property); | |
247 | ||
248 | struct device_node *__of_find_all_nodes(struct device_node *prev) | |
249 | { | |
250 | struct device_node *np; | |
251 | if (!prev) { | |
252 | np = of_root; | |
253 | } else if (prev->child) { | |
254 | np = prev->child; | |
255 | } else { | |
256 | /* Walk back up looking for a sibling, or the end of the structure */ | |
257 | np = prev; | |
258 | while (np->parent && !np->sibling) | |
259 | np = np->parent; | |
260 | np = np->sibling; /* Might be null at the end of the tree */ | |
261 | } | |
262 | return np; | |
263 | } | |
264 | ||
265 | /** | |
266 | * of_find_all_nodes - Get next node in global list | |
267 | * @prev: Previous node or NULL to start iteration | |
268 | * of_node_put() will be called on it | |
269 | * | |
270 | * Returns a node pointer with refcount incremented, use | |
271 | * of_node_put() on it when done. | |
272 | */ | |
273 | struct device_node *of_find_all_nodes(struct device_node *prev) | |
274 | { | |
275 | struct device_node *np; | |
276 | unsigned long flags; | |
277 | ||
278 | raw_spin_lock_irqsave(&devtree_lock, flags); | |
279 | np = __of_find_all_nodes(prev); | |
280 | of_node_get(np); | |
281 | of_node_put(prev); | |
282 | raw_spin_unlock_irqrestore(&devtree_lock, flags); | |
283 | return np; | |
284 | } | |
285 | EXPORT_SYMBOL(of_find_all_nodes); | |
286 | ||
287 | /* | |
288 | * Find a property with a given name for a given node | |
289 | * and return the value. | |
290 | */ | |
291 | const void *__of_get_property(const struct device_node *np, | |
292 | const char *name, int *lenp) | |
293 | { | |
294 | struct property *pp = __of_find_property(np, name, lenp); | |
295 | ||
296 | return pp ? pp->value : NULL; | |
297 | } | |
298 | ||
299 | /* | |
300 | * Find a property with a given name for a given node | |
301 | * and return the value. | |
302 | */ | |
303 | const void *of_get_property(const struct device_node *np, const char *name, | |
304 | int *lenp) | |
305 | { | |
306 | struct property *pp = of_find_property(np, name, lenp); | |
307 | ||
308 | return pp ? pp->value : NULL; | |
309 | } | |
310 | EXPORT_SYMBOL(of_get_property); | |
311 | ||
312 | /* | |
313 | * arch_match_cpu_phys_id - Match the given logical CPU and physical id | |
314 | * | |
315 | * @cpu: logical cpu index of a core/thread | |
316 | * @phys_id: physical identifier of a core/thread | |
317 | * | |
318 | * CPU logical to physical index mapping is architecture specific. | |
319 | * However this __weak function provides a default match of physical | |
320 | * id to logical cpu index. phys_id provided here is usually values read | |
321 | * from the device tree which must match the hardware internal registers. | |
322 | * | |
323 | * Returns true if the physical identifier and the logical cpu index | |
324 | * correspond to the same core/thread, false otherwise. | |
325 | */ | |
326 | bool __weak arch_match_cpu_phys_id(int cpu, u64 phys_id) | |
327 | { | |
328 | return (u32)phys_id == cpu; | |
329 | } | |
330 | ||
331 | /** | |
332 | * Checks if the given "prop_name" property holds the physical id of the | |
333 | * core/thread corresponding to the logical cpu 'cpu'. If 'thread' is not | |
334 | * NULL, local thread number within the core is returned in it. | |
335 | */ | |
336 | static bool __of_find_n_match_cpu_property(struct device_node *cpun, | |
337 | const char *prop_name, int cpu, unsigned int *thread) | |
338 | { | |
339 | const __be32 *cell; | |
340 | int ac, prop_len, tid; | |
341 | u64 hwid; | |
342 | ||
343 | ac = of_n_addr_cells(cpun); | |
344 | cell = of_get_property(cpun, prop_name, &prop_len); | |
345 | if (!cell || !ac) | |
346 | return false; | |
347 | prop_len /= sizeof(*cell) * ac; | |
348 | for (tid = 0; tid < prop_len; tid++) { | |
349 | hwid = of_read_number(cell, ac); | |
350 | if (arch_match_cpu_phys_id(cpu, hwid)) { | |
351 | if (thread) | |
352 | *thread = tid; | |
353 | return true; | |
354 | } | |
355 | cell += ac; | |
356 | } | |
357 | return false; | |
358 | } | |
359 | ||
360 | /* | |
361 | * arch_find_n_match_cpu_physical_id - See if the given device node is | |
362 | * for the cpu corresponding to logical cpu 'cpu'. Return true if so, | |
363 | * else false. If 'thread' is non-NULL, the local thread number within the | |
364 | * core is returned in it. | |
365 | */ | |
366 | bool __weak arch_find_n_match_cpu_physical_id(struct device_node *cpun, | |
367 | int cpu, unsigned int *thread) | |
368 | { | |
369 | /* Check for non-standard "ibm,ppc-interrupt-server#s" property | |
370 | * for thread ids on PowerPC. If it doesn't exist fallback to | |
371 | * standard "reg" property. | |
372 | */ | |
373 | if (IS_ENABLED(CONFIG_PPC) && | |
374 | __of_find_n_match_cpu_property(cpun, | |
375 | "ibm,ppc-interrupt-server#s", | |
376 | cpu, thread)) | |
377 | return true; | |
378 | ||
379 | if (__of_find_n_match_cpu_property(cpun, "reg", cpu, thread)) | |
380 | return true; | |
381 | ||
382 | return false; | |
383 | } | |
384 | ||
385 | /** | |
386 | * of_get_cpu_node - Get device node associated with the given logical CPU | |
387 | * | |
388 | * @cpu: CPU number(logical index) for which device node is required | |
389 | * @thread: if not NULL, local thread number within the physical core is | |
390 | * returned | |
391 | * | |
392 | * The main purpose of this function is to retrieve the device node for the | |
393 | * given logical CPU index. It should be used to initialize the of_node in | |
394 | * cpu device. Once of_node in cpu device is populated, all the further | |
395 | * references can use that instead. | |
396 | * | |
397 | * CPU logical to physical index mapping is architecture specific and is built | |
398 | * before booting secondary cores. This function uses arch_match_cpu_phys_id | |
399 | * which can be overridden by architecture specific implementation. | |
400 | * | |
401 | * Returns a node pointer for the logical cpu if found, else NULL. | |
402 | */ | |
403 | struct device_node *of_get_cpu_node(int cpu, unsigned int *thread) | |
404 | { | |
405 | struct device_node *cpun; | |
406 | ||
407 | for_each_node_by_type(cpun, "cpu") { | |
408 | if (arch_find_n_match_cpu_physical_id(cpun, cpu, thread)) | |
409 | return cpun; | |
410 | } | |
411 | return NULL; | |
412 | } | |
413 | EXPORT_SYMBOL(of_get_cpu_node); | |
414 | ||
415 | /** | |
416 | * __of_device_is_compatible() - Check if the node matches given constraints | |
417 | * @device: pointer to node | |
418 | * @compat: required compatible string, NULL or "" for any match | |
419 | * @type: required device_type value, NULL or "" for any match | |
420 | * @name: required node name, NULL or "" for any match | |
421 | * | |
422 | * Checks if the given @compat, @type and @name strings match the | |
423 | * properties of the given @device. A constraints can be skipped by | |
424 | * passing NULL or an empty string as the constraint. | |
425 | * | |
426 | * Returns 0 for no match, and a positive integer on match. The return | |
427 | * value is a relative score with larger values indicating better | |
428 | * matches. The score is weighted for the most specific compatible value | |
429 | * to get the highest score. Matching type is next, followed by matching | |
430 | * name. Practically speaking, this results in the following priority | |
431 | * order for matches: | |
432 | * | |
433 | * 1. specific compatible && type && name | |
434 | * 2. specific compatible && type | |
435 | * 3. specific compatible && name | |
436 | * 4. specific compatible | |
437 | * 5. general compatible && type && name | |
438 | * 6. general compatible && type | |
439 | * 7. general compatible && name | |
440 | * 8. general compatible | |
441 | * 9. type && name | |
442 | * 10. type | |
443 | * 11. name | |
444 | */ | |
445 | static int __of_device_is_compatible(const struct device_node *device, | |
446 | const char *compat, const char *type, const char *name) | |
447 | { | |
448 | struct property *prop; | |
449 | const char *cp; | |
450 | int index = 0, score = 0; | |
451 | ||
452 | /* Compatible match has highest priority */ | |
453 | if (compat && compat[0]) { | |
454 | prop = __of_find_property(device, "compatible", NULL); | |
455 | for (cp = of_prop_next_string(prop, NULL); cp; | |
456 | cp = of_prop_next_string(prop, cp), index++) { | |
457 | if (of_compat_cmp(cp, compat, strlen(compat)) == 0) { | |
458 | score = INT_MAX/2 - (index << 2); | |
459 | break; | |
460 | } | |
461 | } | |
462 | if (!score) | |
463 | return 0; | |
464 | } | |
465 | ||
466 | /* Matching type is better than matching name */ | |
467 | if (type && type[0]) { | |
468 | if (!device->type || of_node_cmp(type, device->type)) | |
469 | return 0; | |
470 | score += 2; | |
471 | } | |
472 | ||
473 | /* Matching name is a bit better than not */ | |
474 | if (name && name[0]) { | |
475 | if (!device->name || of_node_cmp(name, device->name)) | |
476 | return 0; | |
477 | score++; | |
478 | } | |
479 | ||
480 | return score; | |
481 | } | |
482 | ||
483 | /** Checks if the given "compat" string matches one of the strings in | |
484 | * the device's "compatible" property | |
485 | */ | |
486 | int of_device_is_compatible(const struct device_node *device, | |
487 | const char *compat) | |
488 | { | |
489 | unsigned long flags; | |
490 | int res; | |
491 | ||
492 | raw_spin_lock_irqsave(&devtree_lock, flags); | |
493 | res = __of_device_is_compatible(device, compat, NULL, NULL); | |
494 | raw_spin_unlock_irqrestore(&devtree_lock, flags); | |
495 | return res; | |
496 | } | |
497 | EXPORT_SYMBOL(of_device_is_compatible); | |
498 | ||
499 | /** | |
500 | * of_machine_is_compatible - Test root of device tree for a given compatible value | |
501 | * @compat: compatible string to look for in root node's compatible property. | |
502 | * | |
503 | * Returns true if the root node has the given value in its | |
504 | * compatible property. | |
505 | */ | |
506 | int of_machine_is_compatible(const char *compat) | |
507 | { | |
508 | struct device_node *root; | |
509 | int rc = 0; | |
510 | ||
511 | root = of_find_node_by_path("/"); | |
512 | if (root) { | |
513 | rc = of_device_is_compatible(root, compat); | |
514 | of_node_put(root); | |
515 | } | |
516 | return rc; | |
517 | } | |
518 | EXPORT_SYMBOL(of_machine_is_compatible); | |
519 | ||
520 | /** | |
521 | * __of_device_is_available - check if a device is available for use | |
522 | * | |
523 | * @device: Node to check for availability, with locks already held | |
524 | * | |
525 | * Returns 1 if the status property is absent or set to "okay" or "ok", | |
526 | * 0 otherwise | |
527 | */ | |
528 | static int __of_device_is_available(const struct device_node *device) | |
529 | { | |
530 | const char *status; | |
531 | int statlen; | |
532 | ||
533 | if (!device) | |
534 | return 0; | |
535 | ||
536 | status = __of_get_property(device, "status", &statlen); | |
537 | if (status == NULL) | |
538 | return 1; | |
539 | ||
540 | if (statlen > 0) { | |
541 | if (!strcmp(status, "okay") || !strcmp(status, "ok")) | |
542 | return 1; | |
543 | } | |
544 | ||
545 | return 0; | |
546 | } | |
547 | ||
548 | /** | |
549 | * of_device_is_available - check if a device is available for use | |
550 | * | |
551 | * @device: Node to check for availability | |
552 | * | |
553 | * Returns 1 if the status property is absent or set to "okay" or "ok", | |
554 | * 0 otherwise | |
555 | */ | |
556 | int of_device_is_available(const struct device_node *device) | |
557 | { | |
558 | unsigned long flags; | |
559 | int res; | |
560 | ||
561 | raw_spin_lock_irqsave(&devtree_lock, flags); | |
562 | res = __of_device_is_available(device); | |
563 | raw_spin_unlock_irqrestore(&devtree_lock, flags); | |
564 | return res; | |
565 | ||
566 | } | |
567 | EXPORT_SYMBOL(of_device_is_available); | |
568 | ||
569 | /** | |
570 | * of_get_parent - Get a node's parent if any | |
571 | * @node: Node to get parent | |
572 | * | |
573 | * Returns a node pointer with refcount incremented, use | |
574 | * of_node_put() on it when done. | |
575 | */ | |
576 | struct device_node *of_get_parent(const struct device_node *node) | |
577 | { | |
578 | struct device_node *np; | |
579 | unsigned long flags; | |
580 | ||
581 | if (!node) | |
582 | return NULL; | |
583 | ||
584 | raw_spin_lock_irqsave(&devtree_lock, flags); | |
585 | np = of_node_get(node->parent); | |
586 | raw_spin_unlock_irqrestore(&devtree_lock, flags); | |
587 | return np; | |
588 | } | |
589 | EXPORT_SYMBOL(of_get_parent); | |
590 | ||
591 | /** | |
592 | * of_get_next_parent - Iterate to a node's parent | |
593 | * @node: Node to get parent of | |
594 | * | |
595 | * This is like of_get_parent() except that it drops the | |
596 | * refcount on the passed node, making it suitable for iterating | |
597 | * through a node's parents. | |
598 | * | |
599 | * Returns a node pointer with refcount incremented, use | |
600 | * of_node_put() on it when done. | |
601 | */ | |
602 | struct device_node *of_get_next_parent(struct device_node *node) | |
603 | { | |
604 | struct device_node *parent; | |
605 | unsigned long flags; | |
606 | ||
607 | if (!node) | |
608 | return NULL; | |
609 | ||
610 | raw_spin_lock_irqsave(&devtree_lock, flags); | |
611 | parent = of_node_get(node->parent); | |
612 | of_node_put(node); | |
613 | raw_spin_unlock_irqrestore(&devtree_lock, flags); | |
614 | return parent; | |
615 | } | |
616 | EXPORT_SYMBOL(of_get_next_parent); | |
617 | ||
618 | static struct device_node *__of_get_next_child(const struct device_node *node, | |
619 | struct device_node *prev) | |
620 | { | |
621 | struct device_node *next; | |
622 | ||
623 | if (!node) | |
624 | return NULL; | |
625 | ||
626 | next = prev ? prev->sibling : node->child; | |
627 | for (; next; next = next->sibling) | |
628 | if (of_node_get(next)) | |
629 | break; | |
630 | of_node_put(prev); | |
631 | return next; | |
632 | } | |
633 | #define __for_each_child_of_node(parent, child) \ | |
634 | for (child = __of_get_next_child(parent, NULL); child != NULL; \ | |
635 | child = __of_get_next_child(parent, child)) | |
636 | ||
637 | /** | |
638 | * of_get_next_child - Iterate a node childs | |
639 | * @node: parent node | |
640 | * @prev: previous child of the parent node, or NULL to get first | |
641 | * | |
642 | * Returns a node pointer with refcount incremented, use | |
643 | * of_node_put() on it when done. | |
644 | */ | |
645 | struct device_node *of_get_next_child(const struct device_node *node, | |
646 | struct device_node *prev) | |
647 | { | |
648 | struct device_node *next; | |
649 | unsigned long flags; | |
650 | ||
651 | raw_spin_lock_irqsave(&devtree_lock, flags); | |
652 | next = __of_get_next_child(node, prev); | |
653 | raw_spin_unlock_irqrestore(&devtree_lock, flags); | |
654 | return next; | |
655 | } | |
656 | EXPORT_SYMBOL(of_get_next_child); | |
657 | ||
658 | /** | |
659 | * of_get_next_available_child - Find the next available child node | |
660 | * @node: parent node | |
661 | * @prev: previous child of the parent node, or NULL to get first | |
662 | * | |
663 | * This function is like of_get_next_child(), except that it | |
664 | * automatically skips any disabled nodes (i.e. status = "disabled"). | |
665 | */ | |
666 | struct device_node *of_get_next_available_child(const struct device_node *node, | |
667 | struct device_node *prev) | |
668 | { | |
669 | struct device_node *next; | |
670 | unsigned long flags; | |
671 | ||
672 | if (!node) | |
673 | return NULL; | |
674 | ||
675 | raw_spin_lock_irqsave(&devtree_lock, flags); | |
676 | next = prev ? prev->sibling : node->child; | |
677 | for (; next; next = next->sibling) { | |
678 | if (!__of_device_is_available(next)) | |
679 | continue; | |
680 | if (of_node_get(next)) | |
681 | break; | |
682 | } | |
683 | of_node_put(prev); | |
684 | raw_spin_unlock_irqrestore(&devtree_lock, flags); | |
685 | return next; | |
686 | } | |
687 | EXPORT_SYMBOL(of_get_next_available_child); | |
688 | ||
689 | /** | |
690 | * of_get_child_by_name - Find the child node by name for a given parent | |
691 | * @node: parent node | |
692 | * @name: child name to look for. | |
693 | * | |
694 | * This function looks for child node for given matching name | |
695 | * | |
696 | * Returns a node pointer if found, with refcount incremented, use | |
697 | * of_node_put() on it when done. | |
698 | * Returns NULL if node is not found. | |
699 | */ | |
700 | struct device_node *of_get_child_by_name(const struct device_node *node, | |
701 | const char *name) | |
702 | { | |
703 | struct device_node *child; | |
704 | ||
705 | for_each_child_of_node(node, child) | |
706 | if (child->name && (of_node_cmp(child->name, name) == 0)) | |
707 | break; | |
708 | return child; | |
709 | } | |
710 | EXPORT_SYMBOL(of_get_child_by_name); | |
711 | ||
712 | static struct device_node *__of_find_node_by_path(struct device_node *parent, | |
713 | const char *path) | |
714 | { | |
715 | struct device_node *child; | |
716 | int len = strchrnul(path, '/') - path; | |
717 | ||
718 | if (!len) | |
719 | return NULL; | |
720 | ||
721 | __for_each_child_of_node(parent, child) { | |
722 | const char *name = strrchr(child->full_name, '/'); | |
723 | if (WARN(!name, "malformed device_node %s\n", child->full_name)) | |
724 | continue; | |
725 | name++; | |
726 | if (strncmp(path, name, len) == 0 && (strlen(name) == len)) | |
727 | return child; | |
728 | } | |
729 | return NULL; | |
730 | } | |
731 | ||
732 | /** | |
733 | * of_find_node_by_path - Find a node matching a full OF path | |
734 | * @path: Either the full path to match, or if the path does not | |
735 | * start with '/', the name of a property of the /aliases | |
736 | * node (an alias). In the case of an alias, the node | |
737 | * matching the alias' value will be returned. | |
738 | * | |
739 | * Valid paths: | |
740 | * /foo/bar Full path | |
741 | * foo Valid alias | |
742 | * foo/bar Valid alias + relative path | |
743 | * | |
744 | * Returns a node pointer with refcount incremented, use | |
745 | * of_node_put() on it when done. | |
746 | */ | |
747 | struct device_node *of_find_node_by_path(const char *path) | |
748 | { | |
749 | struct device_node *np = NULL; | |
750 | struct property *pp; | |
751 | unsigned long flags; | |
752 | ||
753 | if (strcmp(path, "/") == 0) | |
754 | return of_node_get(of_root); | |
755 | ||
756 | /* The path could begin with an alias */ | |
757 | if (*path != '/') { | |
758 | char *p = strchrnul(path, '/'); | |
759 | int len = p - path; | |
760 | ||
761 | /* of_aliases must not be NULL */ | |
762 | if (!of_aliases) | |
763 | return NULL; | |
764 | ||
765 | for_each_property_of_node(of_aliases, pp) { | |
766 | if (strlen(pp->name) == len && !strncmp(pp->name, path, len)) { | |
767 | np = of_find_node_by_path(pp->value); | |
768 | break; | |
769 | } | |
770 | } | |
771 | if (!np) | |
772 | return NULL; | |
773 | path = p; | |
774 | } | |
775 | ||
776 | /* Step down the tree matching path components */ | |
777 | raw_spin_lock_irqsave(&devtree_lock, flags); | |
778 | if (!np) | |
779 | np = of_node_get(of_root); | |
780 | while (np && *path == '/') { | |
781 | path++; /* Increment past '/' delimiter */ | |
782 | np = __of_find_node_by_path(np, path); | |
783 | path = strchrnul(path, '/'); | |
784 | } | |
785 | raw_spin_unlock_irqrestore(&devtree_lock, flags); | |
786 | return np; | |
787 | } | |
788 | EXPORT_SYMBOL(of_find_node_by_path); | |
789 | ||
790 | /** | |
791 | * of_find_node_by_name - Find a node by its "name" property | |
792 | * @from: The node to start searching from or NULL, the node | |
793 | * you pass will not be searched, only the next one | |
794 | * will; typically, you pass what the previous call | |
795 | * returned. of_node_put() will be called on it | |
796 | * @name: The name string to match against | |
797 | * | |
798 | * Returns a node pointer with refcount incremented, use | |
799 | * of_node_put() on it when done. | |
800 | */ | |
801 | struct device_node *of_find_node_by_name(struct device_node *from, | |
802 | const char *name) | |
803 | { | |
804 | struct device_node *np; | |
805 | unsigned long flags; | |
806 | ||
807 | raw_spin_lock_irqsave(&devtree_lock, flags); | |
808 | for_each_of_allnodes_from(from, np) | |
809 | if (np->name && (of_node_cmp(np->name, name) == 0) | |
810 | && of_node_get(np)) | |
811 | break; | |
812 | of_node_put(from); | |
813 | raw_spin_unlock_irqrestore(&devtree_lock, flags); | |
814 | return np; | |
815 | } | |
816 | EXPORT_SYMBOL(of_find_node_by_name); | |
817 | ||
818 | /** | |
819 | * of_find_node_by_type - Find a node by its "device_type" property | |
820 | * @from: The node to start searching from, or NULL to start searching | |
821 | * the entire device tree. The node you pass will not be | |
822 | * searched, only the next one will; typically, you pass | |
823 | * what the previous call returned. of_node_put() will be | |
824 | * called on from for you. | |
825 | * @type: The type string to match against | |
826 | * | |
827 | * Returns a node pointer with refcount incremented, use | |
828 | * of_node_put() on it when done. | |
829 | */ | |
830 | struct device_node *of_find_node_by_type(struct device_node *from, | |
831 | const char *type) | |
832 | { | |
833 | struct device_node *np; | |
834 | unsigned long flags; | |
835 | ||
836 | raw_spin_lock_irqsave(&devtree_lock, flags); | |
837 | for_each_of_allnodes_from(from, np) | |
838 | if (np->type && (of_node_cmp(np->type, type) == 0) | |
839 | && of_node_get(np)) | |
840 | break; | |
841 | of_node_put(from); | |
842 | raw_spin_unlock_irqrestore(&devtree_lock, flags); | |
843 | return np; | |
844 | } | |
845 | EXPORT_SYMBOL(of_find_node_by_type); | |
846 | ||
847 | /** | |
848 | * of_find_compatible_node - Find a node based on type and one of the | |
849 | * tokens in its "compatible" property | |
850 | * @from: The node to start searching from or NULL, the node | |
851 | * you pass will not be searched, only the next one | |
852 | * will; typically, you pass what the previous call | |
853 | * returned. of_node_put() will be called on it | |
854 | * @type: The type string to match "device_type" or NULL to ignore | |
855 | * @compatible: The string to match to one of the tokens in the device | |
856 | * "compatible" list. | |
857 | * | |
858 | * Returns a node pointer with refcount incremented, use | |
859 | * of_node_put() on it when done. | |
860 | */ | |
861 | struct device_node *of_find_compatible_node(struct device_node *from, | |
862 | const char *type, const char *compatible) | |
863 | { | |
864 | struct device_node *np; | |
865 | unsigned long flags; | |
866 | ||
867 | raw_spin_lock_irqsave(&devtree_lock, flags); | |
868 | for_each_of_allnodes_from(from, np) | |
869 | if (__of_device_is_compatible(np, compatible, type, NULL) && | |
870 | of_node_get(np)) | |
871 | break; | |
872 | of_node_put(from); | |
873 | raw_spin_unlock_irqrestore(&devtree_lock, flags); | |
874 | return np; | |
875 | } | |
876 | EXPORT_SYMBOL(of_find_compatible_node); | |
877 | ||
878 | /** | |
879 | * of_find_node_with_property - Find a node which has a property with | |
880 | * the given name. | |
881 | * @from: The node to start searching from or NULL, the node | |
882 | * you pass will not be searched, only the next one | |
883 | * will; typically, you pass what the previous call | |
884 | * returned. of_node_put() will be called on it | |
885 | * @prop_name: The name of the property to look for. | |
886 | * | |
887 | * Returns a node pointer with refcount incremented, use | |
888 | * of_node_put() on it when done. | |
889 | */ | |
890 | struct device_node *of_find_node_with_property(struct device_node *from, | |
891 | const char *prop_name) | |
892 | { | |
893 | struct device_node *np; | |
894 | struct property *pp; | |
895 | unsigned long flags; | |
896 | ||
897 | raw_spin_lock_irqsave(&devtree_lock, flags); | |
898 | for_each_of_allnodes_from(from, np) { | |
899 | for (pp = np->properties; pp; pp = pp->next) { | |
900 | if (of_prop_cmp(pp->name, prop_name) == 0) { | |
901 | of_node_get(np); | |
902 | goto out; | |
903 | } | |
904 | } | |
905 | } | |
906 | out: | |
907 | of_node_put(from); | |
908 | raw_spin_unlock_irqrestore(&devtree_lock, flags); | |
909 | return np; | |
910 | } | |
911 | EXPORT_SYMBOL(of_find_node_with_property); | |
912 | ||
913 | static | |
914 | const struct of_device_id *__of_match_node(const struct of_device_id *matches, | |
915 | const struct device_node *node) | |
916 | { | |
917 | const struct of_device_id *best_match = NULL; | |
918 | int score, best_score = 0; | |
919 | ||
920 | if (!matches) | |
921 | return NULL; | |
922 | ||
923 | for (; matches->name[0] || matches->type[0] || matches->compatible[0]; matches++) { | |
924 | score = __of_device_is_compatible(node, matches->compatible, | |
925 | matches->type, matches->name); | |
926 | if (score > best_score) { | |
927 | best_match = matches; | |
928 | best_score = score; | |
929 | } | |
930 | } | |
931 | ||
932 | return best_match; | |
933 | } | |
934 | ||
935 | /** | |
936 | * of_match_node - Tell if an device_node has a matching of_match structure | |
937 | * @matches: array of of device match structures to search in | |
938 | * @node: the of device structure to match against | |
939 | * | |
940 | * Low level utility function used by device matching. | |
941 | */ | |
942 | const struct of_device_id *of_match_node(const struct of_device_id *matches, | |
943 | const struct device_node *node) | |
944 | { | |
945 | const struct of_device_id *match; | |
946 | unsigned long flags; | |
947 | ||
948 | raw_spin_lock_irqsave(&devtree_lock, flags); | |
949 | match = __of_match_node(matches, node); | |
950 | raw_spin_unlock_irqrestore(&devtree_lock, flags); | |
951 | return match; | |
952 | } | |
953 | EXPORT_SYMBOL(of_match_node); | |
954 | ||
955 | /** | |
956 | * of_find_matching_node_and_match - Find a node based on an of_device_id | |
957 | * match table. | |
958 | * @from: The node to start searching from or NULL, the node | |
959 | * you pass will not be searched, only the next one | |
960 | * will; typically, you pass what the previous call | |
961 | * returned. of_node_put() will be called on it | |
962 | * @matches: array of of device match structures to search in | |
963 | * @match Updated to point at the matches entry which matched | |
964 | * | |
965 | * Returns a node pointer with refcount incremented, use | |
966 | * of_node_put() on it when done. | |
967 | */ | |
968 | struct device_node *of_find_matching_node_and_match(struct device_node *from, | |
969 | const struct of_device_id *matches, | |
970 | const struct of_device_id **match) | |
971 | { | |
972 | struct device_node *np; | |
973 | const struct of_device_id *m; | |
974 | unsigned long flags; | |
975 | ||
976 | if (match) | |
977 | *match = NULL; | |
978 | ||
979 | raw_spin_lock_irqsave(&devtree_lock, flags); | |
980 | for_each_of_allnodes_from(from, np) { | |
981 | m = __of_match_node(matches, np); | |
982 | if (m && of_node_get(np)) { | |
983 | if (match) | |
984 | *match = m; | |
985 | break; | |
986 | } | |
987 | } | |
988 | of_node_put(from); | |
989 | raw_spin_unlock_irqrestore(&devtree_lock, flags); | |
990 | return np; | |
991 | } | |
992 | EXPORT_SYMBOL(of_find_matching_node_and_match); | |
993 | ||
994 | /** | |
995 | * of_modalias_node - Lookup appropriate modalias for a device node | |
996 | * @node: pointer to a device tree node | |
997 | * @modalias: Pointer to buffer that modalias value will be copied into | |
998 | * @len: Length of modalias value | |
999 | * | |
1000 | * Based on the value of the compatible property, this routine will attempt | |
1001 | * to choose an appropriate modalias value for a particular device tree node. | |
1002 | * It does this by stripping the manufacturer prefix (as delimited by a ',') | |
1003 | * from the first entry in the compatible list property. | |
1004 | * | |
1005 | * This routine returns 0 on success, <0 on failure. | |
1006 | */ | |
1007 | int of_modalias_node(struct device_node *node, char *modalias, int len) | |
1008 | { | |
1009 | const char *compatible, *p; | |
1010 | int cplen; | |
1011 | ||
1012 | compatible = of_get_property(node, "compatible", &cplen); | |
1013 | if (!compatible || strlen(compatible) > cplen) | |
1014 | return -ENODEV; | |
1015 | p = strchr(compatible, ','); | |
1016 | strlcpy(modalias, p ? p + 1 : compatible, len); | |
1017 | return 0; | |
1018 | } | |
1019 | EXPORT_SYMBOL_GPL(of_modalias_node); | |
1020 | ||
1021 | /** | |
1022 | * of_find_node_by_phandle - Find a node given a phandle | |
1023 | * @handle: phandle of the node to find | |
1024 | * | |
1025 | * Returns a node pointer with refcount incremented, use | |
1026 | * of_node_put() on it when done. | |
1027 | */ | |
1028 | struct device_node *of_find_node_by_phandle(phandle handle) | |
1029 | { | |
1030 | struct device_node *np; | |
1031 | unsigned long flags; | |
1032 | ||
1033 | if (!handle) | |
1034 | return NULL; | |
1035 | ||
1036 | raw_spin_lock_irqsave(&devtree_lock, flags); | |
1037 | for_each_of_allnodes(np) | |
1038 | if (np->phandle == handle) | |
1039 | break; | |
1040 | of_node_get(np); | |
1041 | raw_spin_unlock_irqrestore(&devtree_lock, flags); | |
1042 | return np; | |
1043 | } | |
1044 | EXPORT_SYMBOL(of_find_node_by_phandle); | |
1045 | ||
1046 | /** | |
1047 | * of_property_count_elems_of_size - Count the number of elements in a property | |
1048 | * | |
1049 | * @np: device node from which the property value is to be read. | |
1050 | * @propname: name of the property to be searched. | |
1051 | * @elem_size: size of the individual element | |
1052 | * | |
1053 | * Search for a property in a device node and count the number of elements of | |
1054 | * size elem_size in it. Returns number of elements on sucess, -EINVAL if the | |
1055 | * property does not exist or its length does not match a multiple of elem_size | |
1056 | * and -ENODATA if the property does not have a value. | |
1057 | */ | |
1058 | int of_property_count_elems_of_size(const struct device_node *np, | |
1059 | const char *propname, int elem_size) | |
1060 | { | |
1061 | struct property *prop = of_find_property(np, propname, NULL); | |
1062 | ||
1063 | if (!prop) | |
1064 | return -EINVAL; | |
1065 | if (!prop->value) | |
1066 | return -ENODATA; | |
1067 | ||
1068 | if (prop->length % elem_size != 0) { | |
1069 | pr_err("size of %s in node %s is not a multiple of %d\n", | |
1070 | propname, np->full_name, elem_size); | |
1071 | return -EINVAL; | |
1072 | } | |
1073 | ||
1074 | return prop->length / elem_size; | |
1075 | } | |
1076 | EXPORT_SYMBOL_GPL(of_property_count_elems_of_size); | |
1077 | ||
1078 | /** | |
1079 | * of_find_property_value_of_size | |
1080 | * | |
1081 | * @np: device node from which the property value is to be read. | |
1082 | * @propname: name of the property to be searched. | |
1083 | * @len: requested length of property value | |
1084 | * | |
1085 | * Search for a property in a device node and valid the requested size. | |
1086 | * Returns the property value on success, -EINVAL if the property does not | |
1087 | * exist, -ENODATA if property does not have a value, and -EOVERFLOW if the | |
1088 | * property data isn't large enough. | |
1089 | * | |
1090 | */ | |
1091 | static void *of_find_property_value_of_size(const struct device_node *np, | |
1092 | const char *propname, u32 len) | |
1093 | { | |
1094 | struct property *prop = of_find_property(np, propname, NULL); | |
1095 | ||
1096 | if (!prop) | |
1097 | return ERR_PTR(-EINVAL); | |
1098 | if (!prop->value) | |
1099 | return ERR_PTR(-ENODATA); | |
1100 | if (len > prop->length) | |
1101 | return ERR_PTR(-EOVERFLOW); | |
1102 | ||
1103 | return prop->value; | |
1104 | } | |
1105 | ||
1106 | /** | |
1107 | * of_property_read_u32_index - Find and read a u32 from a multi-value property. | |
1108 | * | |
1109 | * @np: device node from which the property value is to be read. | |
1110 | * @propname: name of the property to be searched. | |
1111 | * @index: index of the u32 in the list of values | |
1112 | * @out_value: pointer to return value, modified only if no error. | |
1113 | * | |
1114 | * Search for a property in a device node and read nth 32-bit value from | |
1115 | * it. Returns 0 on success, -EINVAL if the property does not exist, | |
1116 | * -ENODATA if property does not have a value, and -EOVERFLOW if the | |
1117 | * property data isn't large enough. | |
1118 | * | |
1119 | * The out_value is modified only if a valid u32 value can be decoded. | |
1120 | */ | |
1121 | int of_property_read_u32_index(const struct device_node *np, | |
1122 | const char *propname, | |
1123 | u32 index, u32 *out_value) | |
1124 | { | |
1125 | const u32 *val = of_find_property_value_of_size(np, propname, | |
1126 | ((index + 1) * sizeof(*out_value))); | |
1127 | ||
1128 | if (IS_ERR(val)) | |
1129 | return PTR_ERR(val); | |
1130 | ||
1131 | *out_value = be32_to_cpup(((__be32 *)val) + index); | |
1132 | return 0; | |
1133 | } | |
1134 | EXPORT_SYMBOL_GPL(of_property_read_u32_index); | |
1135 | ||
1136 | /** | |
1137 | * of_property_read_u8_array - Find and read an array of u8 from a property. | |
1138 | * | |
1139 | * @np: device node from which the property value is to be read. | |
1140 | * @propname: name of the property to be searched. | |
1141 | * @out_values: pointer to return value, modified only if return value is 0. | |
1142 | * @sz: number of array elements to read | |
1143 | * | |
1144 | * Search for a property in a device node and read 8-bit value(s) from | |
1145 | * it. Returns 0 on success, -EINVAL if the property does not exist, | |
1146 | * -ENODATA if property does not have a value, and -EOVERFLOW if the | |
1147 | * property data isn't large enough. | |
1148 | * | |
1149 | * dts entry of array should be like: | |
1150 | * property = /bits/ 8 <0x50 0x60 0x70>; | |
1151 | * | |
1152 | * The out_values is modified only if a valid u8 value can be decoded. | |
1153 | */ | |
1154 | int of_property_read_u8_array(const struct device_node *np, | |
1155 | const char *propname, u8 *out_values, size_t sz) | |
1156 | { | |
1157 | const u8 *val = of_find_property_value_of_size(np, propname, | |
1158 | (sz * sizeof(*out_values))); | |
1159 | ||
1160 | if (IS_ERR(val)) | |
1161 | return PTR_ERR(val); | |
1162 | ||
1163 | while (sz--) | |
1164 | *out_values++ = *val++; | |
1165 | return 0; | |
1166 | } | |
1167 | EXPORT_SYMBOL_GPL(of_property_read_u8_array); | |
1168 | ||
1169 | /** | |
1170 | * of_property_read_u16_array - Find and read an array of u16 from a property. | |
1171 | * | |
1172 | * @np: device node from which the property value is to be read. | |
1173 | * @propname: name of the property to be searched. | |
1174 | * @out_values: pointer to return value, modified only if return value is 0. | |
1175 | * @sz: number of array elements to read | |
1176 | * | |
1177 | * Search for a property in a device node and read 16-bit value(s) from | |
1178 | * it. Returns 0 on success, -EINVAL if the property does not exist, | |
1179 | * -ENODATA if property does not have a value, and -EOVERFLOW if the | |
1180 | * property data isn't large enough. | |
1181 | * | |
1182 | * dts entry of array should be like: | |
1183 | * property = /bits/ 16 <0x5000 0x6000 0x7000>; | |
1184 | * | |
1185 | * The out_values is modified only if a valid u16 value can be decoded. | |
1186 | */ | |
1187 | int of_property_read_u16_array(const struct device_node *np, | |
1188 | const char *propname, u16 *out_values, size_t sz) | |
1189 | { | |
1190 | const __be16 *val = of_find_property_value_of_size(np, propname, | |
1191 | (sz * sizeof(*out_values))); | |
1192 | ||
1193 | if (IS_ERR(val)) | |
1194 | return PTR_ERR(val); | |
1195 | ||
1196 | while (sz--) | |
1197 | *out_values++ = be16_to_cpup(val++); | |
1198 | return 0; | |
1199 | } | |
1200 | EXPORT_SYMBOL_GPL(of_property_read_u16_array); | |
1201 | ||
1202 | /** | |
1203 | * of_property_read_u32_array - Find and read an array of 32 bit integers | |
1204 | * from a property. | |
1205 | * | |
1206 | * @np: device node from which the property value is to be read. | |
1207 | * @propname: name of the property to be searched. | |
1208 | * @out_values: pointer to return value, modified only if return value is 0. | |
1209 | * @sz: number of array elements to read | |
1210 | * | |
1211 | * Search for a property in a device node and read 32-bit value(s) from | |
1212 | * it. Returns 0 on success, -EINVAL if the property does not exist, | |
1213 | * -ENODATA if property does not have a value, and -EOVERFLOW if the | |
1214 | * property data isn't large enough. | |
1215 | * | |
1216 | * The out_values is modified only if a valid u32 value can be decoded. | |
1217 | */ | |
1218 | int of_property_read_u32_array(const struct device_node *np, | |
1219 | const char *propname, u32 *out_values, | |
1220 | size_t sz) | |
1221 | { | |
1222 | const __be32 *val = of_find_property_value_of_size(np, propname, | |
1223 | (sz * sizeof(*out_values))); | |
1224 | ||
1225 | if (IS_ERR(val)) | |
1226 | return PTR_ERR(val); | |
1227 | ||
1228 | while (sz--) | |
1229 | *out_values++ = be32_to_cpup(val++); | |
1230 | return 0; | |
1231 | } | |
1232 | EXPORT_SYMBOL_GPL(of_property_read_u32_array); | |
1233 | ||
1234 | /** | |
1235 | * of_property_read_u64 - Find and read a 64 bit integer from a property | |
1236 | * @np: device node from which the property value is to be read. | |
1237 | * @propname: name of the property to be searched. | |
1238 | * @out_value: pointer to return value, modified only if return value is 0. | |
1239 | * | |
1240 | * Search for a property in a device node and read a 64-bit value from | |
1241 | * it. Returns 0 on success, -EINVAL if the property does not exist, | |
1242 | * -ENODATA if property does not have a value, and -EOVERFLOW if the | |
1243 | * property data isn't large enough. | |
1244 | * | |
1245 | * The out_value is modified only if a valid u64 value can be decoded. | |
1246 | */ | |
1247 | int of_property_read_u64(const struct device_node *np, const char *propname, | |
1248 | u64 *out_value) | |
1249 | { | |
1250 | const __be32 *val = of_find_property_value_of_size(np, propname, | |
1251 | sizeof(*out_value)); | |
1252 | ||
1253 | if (IS_ERR(val)) | |
1254 | return PTR_ERR(val); | |
1255 | ||
1256 | *out_value = of_read_number(val, 2); | |
1257 | return 0; | |
1258 | } | |
1259 | EXPORT_SYMBOL_GPL(of_property_read_u64); | |
1260 | ||
1261 | /** | |
1262 | * of_property_read_string - Find and read a string from a property | |
1263 | * @np: device node from which the property value is to be read. | |
1264 | * @propname: name of the property to be searched. | |
1265 | * @out_string: pointer to null terminated return string, modified only if | |
1266 | * return value is 0. | |
1267 | * | |
1268 | * Search for a property in a device tree node and retrieve a null | |
1269 | * terminated string value (pointer to data, not a copy). Returns 0 on | |
1270 | * success, -EINVAL if the property does not exist, -ENODATA if property | |
1271 | * does not have a value, and -EILSEQ if the string is not null-terminated | |
1272 | * within the length of the property data. | |
1273 | * | |
1274 | * The out_string pointer is modified only if a valid string can be decoded. | |
1275 | */ | |
1276 | int of_property_read_string(struct device_node *np, const char *propname, | |
1277 | const char **out_string) | |
1278 | { | |
1279 | struct property *prop = of_find_property(np, propname, NULL); | |
1280 | if (!prop) | |
1281 | return -EINVAL; | |
1282 | if (!prop->value) | |
1283 | return -ENODATA; | |
1284 | if (strnlen(prop->value, prop->length) >= prop->length) | |
1285 | return -EILSEQ; | |
1286 | *out_string = prop->value; | |
1287 | return 0; | |
1288 | } | |
1289 | EXPORT_SYMBOL_GPL(of_property_read_string); | |
1290 | ||
1291 | /** | |
1292 | * of_property_match_string() - Find string in a list and return index | |
1293 | * @np: pointer to node containing string list property | |
1294 | * @propname: string list property name | |
1295 | * @string: pointer to string to search for in string list | |
1296 | * | |
1297 | * This function searches a string list property and returns the index | |
1298 | * of a specific string value. | |
1299 | */ | |
1300 | int of_property_match_string(struct device_node *np, const char *propname, | |
1301 | const char *string) | |
1302 | { | |
1303 | struct property *prop = of_find_property(np, propname, NULL); | |
1304 | size_t l; | |
1305 | int i; | |
1306 | const char *p, *end; | |
1307 | ||
1308 | if (!prop) | |
1309 | return -EINVAL; | |
1310 | if (!prop->value) | |
1311 | return -ENODATA; | |
1312 | ||
1313 | p = prop->value; | |
1314 | end = p + prop->length; | |
1315 | ||
1316 | for (i = 0; p < end; i++, p += l) { | |
1317 | l = strnlen(p, end - p) + 1; | |
1318 | if (p + l > end) | |
1319 | return -EILSEQ; | |
1320 | pr_debug("comparing %s with %s\n", string, p); | |
1321 | if (strcmp(string, p) == 0) | |
1322 | return i; /* Found it; return index */ | |
1323 | } | |
1324 | return -ENODATA; | |
1325 | } | |
1326 | EXPORT_SYMBOL_GPL(of_property_match_string); | |
1327 | ||
1328 | /** | |
1329 | * of_property_read_string_util() - Utility helper for parsing string properties | |
1330 | * @np: device node from which the property value is to be read. | |
1331 | * @propname: name of the property to be searched. | |
1332 | * @out_strs: output array of string pointers. | |
1333 | * @sz: number of array elements to read. | |
1334 | * @skip: Number of strings to skip over at beginning of list. | |
1335 | * | |
1336 | * Don't call this function directly. It is a utility helper for the | |
1337 | * of_property_read_string*() family of functions. | |
1338 | */ | |
1339 | int of_property_read_string_helper(struct device_node *np, const char *propname, | |
1340 | const char **out_strs, size_t sz, int skip) | |
1341 | { | |
1342 | struct property *prop = of_find_property(np, propname, NULL); | |
1343 | int l = 0, i = 0; | |
1344 | const char *p, *end; | |
1345 | ||
1346 | if (!prop) | |
1347 | return -EINVAL; | |
1348 | if (!prop->value) | |
1349 | return -ENODATA; | |
1350 | p = prop->value; | |
1351 | end = p + prop->length; | |
1352 | ||
1353 | for (i = 0; p < end && (!out_strs || i < skip + sz); i++, p += l) { | |
1354 | l = strnlen(p, end - p) + 1; | |
1355 | if (p + l > end) | |
1356 | return -EILSEQ; | |
1357 | if (out_strs && i >= skip) | |
1358 | *out_strs++ = p; | |
1359 | } | |
1360 | i -= skip; | |
1361 | return i <= 0 ? -ENODATA : i; | |
1362 | } | |
1363 | EXPORT_SYMBOL_GPL(of_property_read_string_helper); | |
1364 | ||
1365 | void of_print_phandle_args(const char *msg, const struct of_phandle_args *args) | |
1366 | { | |
1367 | int i; | |
1368 | printk("%s %s", msg, of_node_full_name(args->np)); | |
1369 | for (i = 0; i < args->args_count; i++) | |
1370 | printk(i ? ",%08x" : ":%08x", args->args[i]); | |
1371 | printk("\n"); | |
1372 | } | |
1373 | ||
1374 | static int __of_parse_phandle_with_args(const struct device_node *np, | |
1375 | const char *list_name, | |
1376 | const char *cells_name, | |
1377 | int cell_count, int index, | |
1378 | struct of_phandle_args *out_args) | |
1379 | { | |
1380 | const __be32 *list, *list_end; | |
1381 | int rc = 0, size, cur_index = 0; | |
1382 | uint32_t count = 0; | |
1383 | struct device_node *node = NULL; | |
1384 | phandle phandle; | |
1385 | ||
1386 | /* Retrieve the phandle list property */ | |
1387 | list = of_get_property(np, list_name, &size); | |
1388 | if (!list) | |
1389 | return -ENOENT; | |
1390 | list_end = list + size / sizeof(*list); | |
1391 | ||
1392 | /* Loop over the phandles until all the requested entry is found */ | |
1393 | while (list < list_end) { | |
1394 | rc = -EINVAL; | |
1395 | count = 0; | |
1396 | ||
1397 | /* | |
1398 | * If phandle is 0, then it is an empty entry with no | |
1399 | * arguments. Skip forward to the next entry. | |
1400 | */ | |
1401 | phandle = be32_to_cpup(list++); | |
1402 | if (phandle) { | |
1403 | /* | |
1404 | * Find the provider node and parse the #*-cells | |
1405 | * property to determine the argument length. | |
1406 | * | |
1407 | * This is not needed if the cell count is hard-coded | |
1408 | * (i.e. cells_name not set, but cell_count is set), | |
1409 | * except when we're going to return the found node | |
1410 | * below. | |
1411 | */ | |
1412 | if (cells_name || cur_index == index) { | |
1413 | node = of_find_node_by_phandle(phandle); | |
1414 | if (!node) { | |
1415 | pr_err("%s: could not find phandle\n", | |
1416 | np->full_name); | |
1417 | goto err; | |
1418 | } | |
1419 | } | |
1420 | ||
1421 | if (cells_name) { | |
1422 | if (of_property_read_u32(node, cells_name, | |
1423 | &count)) { | |
1424 | pr_err("%s: could not get %s for %s\n", | |
1425 | np->full_name, cells_name, | |
1426 | node->full_name); | |
1427 | goto err; | |
1428 | } | |
1429 | } else { | |
1430 | count = cell_count; | |
1431 | } | |
1432 | ||
1433 | /* | |
1434 | * Make sure that the arguments actually fit in the | |
1435 | * remaining property data length | |
1436 | */ | |
1437 | if (list + count > list_end) { | |
1438 | pr_err("%s: arguments longer than property\n", | |
1439 | np->full_name); | |
1440 | goto err; | |
1441 | } | |
1442 | } | |
1443 | ||
1444 | /* | |
1445 | * All of the error cases above bail out of the loop, so at | |
1446 | * this point, the parsing is successful. If the requested | |
1447 | * index matches, then fill the out_args structure and return, | |
1448 | * or return -ENOENT for an empty entry. | |
1449 | */ | |
1450 | rc = -ENOENT; | |
1451 | if (cur_index == index) { | |
1452 | if (!phandle) | |
1453 | goto err; | |
1454 | ||
1455 | if (out_args) { | |
1456 | int i; | |
1457 | if (WARN_ON(count > MAX_PHANDLE_ARGS)) | |
1458 | count = MAX_PHANDLE_ARGS; | |
1459 | out_args->np = node; | |
1460 | out_args->args_count = count; | |
1461 | for (i = 0; i < count; i++) | |
1462 | out_args->args[i] = be32_to_cpup(list++); | |
1463 | } else { | |
1464 | of_node_put(node); | |
1465 | } | |
1466 | ||
1467 | /* Found it! return success */ | |
1468 | return 0; | |
1469 | } | |
1470 | ||
1471 | of_node_put(node); | |
1472 | node = NULL; | |
1473 | list += count; | |
1474 | cur_index++; | |
1475 | } | |
1476 | ||
1477 | /* | |
1478 | * Unlock node before returning result; will be one of: | |
1479 | * -ENOENT : index is for empty phandle | |
1480 | * -EINVAL : parsing error on data | |
1481 | * [1..n] : Number of phandle (count mode; when index = -1) | |
1482 | */ | |
1483 | rc = index < 0 ? cur_index : -ENOENT; | |
1484 | err: | |
1485 | if (node) | |
1486 | of_node_put(node); | |
1487 | return rc; | |
1488 | } | |
1489 | ||
1490 | /** | |
1491 | * of_parse_phandle - Resolve a phandle property to a device_node pointer | |
1492 | * @np: Pointer to device node holding phandle property | |
1493 | * @phandle_name: Name of property holding a phandle value | |
1494 | * @index: For properties holding a table of phandles, this is the index into | |
1495 | * the table | |
1496 | * | |
1497 | * Returns the device_node pointer with refcount incremented. Use | |
1498 | * of_node_put() on it when done. | |
1499 | */ | |
1500 | struct device_node *of_parse_phandle(const struct device_node *np, | |
1501 | const char *phandle_name, int index) | |
1502 | { | |
1503 | struct of_phandle_args args; | |
1504 | ||
1505 | if (index < 0) | |
1506 | return NULL; | |
1507 | ||
1508 | if (__of_parse_phandle_with_args(np, phandle_name, NULL, 0, | |
1509 | index, &args)) | |
1510 | return NULL; | |
1511 | ||
1512 | return args.np; | |
1513 | } | |
1514 | EXPORT_SYMBOL(of_parse_phandle); | |
1515 | ||
1516 | /** | |
1517 | * of_parse_phandle_with_args() - Find a node pointed by phandle in a list | |
1518 | * @np: pointer to a device tree node containing a list | |
1519 | * @list_name: property name that contains a list | |
1520 | * @cells_name: property name that specifies phandles' arguments count | |
1521 | * @index: index of a phandle to parse out | |
1522 | * @out_args: optional pointer to output arguments structure (will be filled) | |
1523 | * | |
1524 | * This function is useful to parse lists of phandles and their arguments. | |
1525 | * Returns 0 on success and fills out_args, on error returns appropriate | |
1526 | * errno value. | |
1527 | * | |
1528 | * Caller is responsible to call of_node_put() on the returned out_args->np | |
1529 | * pointer. | |
1530 | * | |
1531 | * Example: | |
1532 | * | |
1533 | * phandle1: node1 { | |
1534 | * #list-cells = <2>; | |
1535 | * } | |
1536 | * | |
1537 | * phandle2: node2 { | |
1538 | * #list-cells = <1>; | |
1539 | * } | |
1540 | * | |
1541 | * node3 { | |
1542 | * list = <&phandle1 1 2 &phandle2 3>; | |
1543 | * } | |
1544 | * | |
1545 | * To get a device_node of the `node2' node you may call this: | |
1546 | * of_parse_phandle_with_args(node3, "list", "#list-cells", 1, &args); | |
1547 | */ | |
1548 | int of_parse_phandle_with_args(const struct device_node *np, const char *list_name, | |
1549 | const char *cells_name, int index, | |
1550 | struct of_phandle_args *out_args) | |
1551 | { | |
1552 | if (index < 0) | |
1553 | return -EINVAL; | |
1554 | return __of_parse_phandle_with_args(np, list_name, cells_name, 0, | |
1555 | index, out_args); | |
1556 | } | |
1557 | EXPORT_SYMBOL(of_parse_phandle_with_args); | |
1558 | ||
1559 | /** | |
1560 | * of_parse_phandle_with_fixed_args() - Find a node pointed by phandle in a list | |
1561 | * @np: pointer to a device tree node containing a list | |
1562 | * @list_name: property name that contains a list | |
1563 | * @cell_count: number of argument cells following the phandle | |
1564 | * @index: index of a phandle to parse out | |
1565 | * @out_args: optional pointer to output arguments structure (will be filled) | |
1566 | * | |
1567 | * This function is useful to parse lists of phandles and their arguments. | |
1568 | * Returns 0 on success and fills out_args, on error returns appropriate | |
1569 | * errno value. | |
1570 | * | |
1571 | * Caller is responsible to call of_node_put() on the returned out_args->np | |
1572 | * pointer. | |
1573 | * | |
1574 | * Example: | |
1575 | * | |
1576 | * phandle1: node1 { | |
1577 | * } | |
1578 | * | |
1579 | * phandle2: node2 { | |
1580 | * } | |
1581 | * | |
1582 | * node3 { | |
1583 | * list = <&phandle1 0 2 &phandle2 2 3>; | |
1584 | * } | |
1585 | * | |
1586 | * To get a device_node of the `node2' node you may call this: | |
1587 | * of_parse_phandle_with_fixed_args(node3, "list", 2, 1, &args); | |
1588 | */ | |
1589 | int of_parse_phandle_with_fixed_args(const struct device_node *np, | |
1590 | const char *list_name, int cell_count, | |
1591 | int index, struct of_phandle_args *out_args) | |
1592 | { | |
1593 | if (index < 0) | |
1594 | return -EINVAL; | |
1595 | return __of_parse_phandle_with_args(np, list_name, NULL, cell_count, | |
1596 | index, out_args); | |
1597 | } | |
1598 | EXPORT_SYMBOL(of_parse_phandle_with_fixed_args); | |
1599 | ||
1600 | /** | |
1601 | * of_count_phandle_with_args() - Find the number of phandles references in a property | |
1602 | * @np: pointer to a device tree node containing a list | |
1603 | * @list_name: property name that contains a list | |
1604 | * @cells_name: property name that specifies phandles' arguments count | |
1605 | * | |
1606 | * Returns the number of phandle + argument tuples within a property. It | |
1607 | * is a typical pattern to encode a list of phandle and variable | |
1608 | * arguments into a single property. The number of arguments is encoded | |
1609 | * by a property in the phandle-target node. For example, a gpios | |
1610 | * property would contain a list of GPIO specifies consisting of a | |
1611 | * phandle and 1 or more arguments. The number of arguments are | |
1612 | * determined by the #gpio-cells property in the node pointed to by the | |
1613 | * phandle. | |
1614 | */ | |
1615 | int of_count_phandle_with_args(const struct device_node *np, const char *list_name, | |
1616 | const char *cells_name) | |
1617 | { | |
1618 | return __of_parse_phandle_with_args(np, list_name, cells_name, 0, -1, | |
1619 | NULL); | |
1620 | } | |
1621 | EXPORT_SYMBOL(of_count_phandle_with_args); | |
1622 | ||
1623 | /** | |
1624 | * __of_add_property - Add a property to a node without lock operations | |
1625 | */ | |
1626 | int __of_add_property(struct device_node *np, struct property *prop) | |
1627 | { | |
1628 | struct property **next; | |
1629 | ||
1630 | prop->next = NULL; | |
1631 | next = &np->properties; | |
1632 | while (*next) { | |
1633 | if (strcmp(prop->name, (*next)->name) == 0) | |
1634 | /* duplicate ! don't insert it */ | |
1635 | return -EEXIST; | |
1636 | ||
1637 | next = &(*next)->next; | |
1638 | } | |
1639 | *next = prop; | |
1640 | ||
1641 | return 0; | |
1642 | } | |
1643 | ||
1644 | /** | |
1645 | * of_add_property - Add a property to a node | |
1646 | */ | |
1647 | int of_add_property(struct device_node *np, struct property *prop) | |
1648 | { | |
1649 | unsigned long flags; | |
1650 | int rc; | |
1651 | ||
1652 | mutex_lock(&of_mutex); | |
1653 | ||
1654 | raw_spin_lock_irqsave(&devtree_lock, flags); | |
1655 | rc = __of_add_property(np, prop); | |
1656 | raw_spin_unlock_irqrestore(&devtree_lock, flags); | |
1657 | ||
1658 | if (!rc) | |
1659 | __of_add_property_sysfs(np, prop); | |
1660 | ||
1661 | mutex_unlock(&of_mutex); | |
1662 | ||
1663 | if (!rc) | |
1664 | of_property_notify(OF_RECONFIG_ADD_PROPERTY, np, prop, NULL); | |
1665 | ||
1666 | return rc; | |
1667 | } | |
1668 | ||
1669 | int __of_remove_property(struct device_node *np, struct property *prop) | |
1670 | { | |
1671 | struct property **next; | |
1672 | ||
1673 | for (next = &np->properties; *next; next = &(*next)->next) { | |
1674 | if (*next == prop) | |
1675 | break; | |
1676 | } | |
1677 | if (*next == NULL) | |
1678 | return -ENODEV; | |
1679 | ||
1680 | /* found the node */ | |
1681 | *next = prop->next; | |
1682 | prop->next = np->deadprops; | |
1683 | np->deadprops = prop; | |
1684 | ||
1685 | return 0; | |
1686 | } | |
1687 | ||
1688 | void __of_remove_property_sysfs(struct device_node *np, struct property *prop) | |
1689 | { | |
1690 | if (!IS_ENABLED(CONFIG_SYSFS)) | |
1691 | return; | |
1692 | ||
1693 | /* at early boot, bail here and defer setup to of_init() */ | |
1694 | if (of_kset && of_node_is_attached(np)) | |
1695 | sysfs_remove_bin_file(&np->kobj, &prop->attr); | |
1696 | } | |
1697 | ||
1698 | /** | |
1699 | * of_remove_property - Remove a property from a node. | |
1700 | * | |
1701 | * Note that we don't actually remove it, since we have given out | |
1702 | * who-knows-how-many pointers to the data using get-property. | |
1703 | * Instead we just move the property to the "dead properties" | |
1704 | * list, so it won't be found any more. | |
1705 | */ | |
1706 | int of_remove_property(struct device_node *np, struct property *prop) | |
1707 | { | |
1708 | unsigned long flags; | |
1709 | int rc; | |
1710 | ||
1711 | mutex_lock(&of_mutex); | |
1712 | ||
1713 | raw_spin_lock_irqsave(&devtree_lock, flags); | |
1714 | rc = __of_remove_property(np, prop); | |
1715 | raw_spin_unlock_irqrestore(&devtree_lock, flags); | |
1716 | ||
1717 | if (!rc) | |
1718 | __of_remove_property_sysfs(np, prop); | |
1719 | ||
1720 | mutex_unlock(&of_mutex); | |
1721 | ||
1722 | if (!rc) | |
1723 | of_property_notify(OF_RECONFIG_REMOVE_PROPERTY, np, prop, NULL); | |
1724 | ||
1725 | return rc; | |
1726 | } | |
1727 | ||
1728 | int __of_update_property(struct device_node *np, struct property *newprop, | |
1729 | struct property **oldpropp) | |
1730 | { | |
1731 | struct property **next, *oldprop; | |
1732 | ||
1733 | for (next = &np->properties; *next; next = &(*next)->next) { | |
1734 | if (of_prop_cmp((*next)->name, newprop->name) == 0) | |
1735 | break; | |
1736 | } | |
1737 | *oldpropp = oldprop = *next; | |
1738 | ||
1739 | if (oldprop) { | |
1740 | /* replace the node */ | |
1741 | newprop->next = oldprop->next; | |
1742 | *next = newprop; | |
1743 | oldprop->next = np->deadprops; | |
1744 | np->deadprops = oldprop; | |
1745 | } else { | |
1746 | /* new node */ | |
1747 | newprop->next = NULL; | |
1748 | *next = newprop; | |
1749 | } | |
1750 | ||
1751 | return 0; | |
1752 | } | |
1753 | ||
1754 | void __of_update_property_sysfs(struct device_node *np, struct property *newprop, | |
1755 | struct property *oldprop) | |
1756 | { | |
1757 | if (!IS_ENABLED(CONFIG_SYSFS)) | |
1758 | return; | |
1759 | ||
1760 | /* At early boot, bail out and defer setup to of_init() */ | |
1761 | if (!of_kset) | |
1762 | return; | |
1763 | ||
1764 | if (oldprop) | |
1765 | sysfs_remove_bin_file(&np->kobj, &oldprop->attr); | |
1766 | __of_add_property_sysfs(np, newprop); | |
1767 | } | |
1768 | ||
1769 | /* | |
1770 | * of_update_property - Update a property in a node, if the property does | |
1771 | * not exist, add it. | |
1772 | * | |
1773 | * Note that we don't actually remove it, since we have given out | |
1774 | * who-knows-how-many pointers to the data using get-property. | |
1775 | * Instead we just move the property to the "dead properties" list, | |
1776 | * and add the new property to the property list | |
1777 | */ | |
1778 | int of_update_property(struct device_node *np, struct property *newprop) | |
1779 | { | |
1780 | struct property *oldprop; | |
1781 | unsigned long flags; | |
1782 | int rc; | |
1783 | ||
1784 | if (!newprop->name) | |
1785 | return -EINVAL; | |
1786 | ||
1787 | mutex_lock(&of_mutex); | |
1788 | ||
1789 | raw_spin_lock_irqsave(&devtree_lock, flags); | |
1790 | rc = __of_update_property(np, newprop, &oldprop); | |
1791 | raw_spin_unlock_irqrestore(&devtree_lock, flags); | |
1792 | ||
1793 | if (!rc) | |
1794 | __of_update_property_sysfs(np, newprop, oldprop); | |
1795 | ||
1796 | mutex_unlock(&of_mutex); | |
1797 | ||
1798 | if (!rc) | |
1799 | of_property_notify(OF_RECONFIG_UPDATE_PROPERTY, np, newprop, oldprop); | |
1800 | ||
1801 | return rc; | |
1802 | } | |
1803 | ||
1804 | static void of_alias_add(struct alias_prop *ap, struct device_node *np, | |
1805 | int id, const char *stem, int stem_len) | |
1806 | { | |
1807 | ap->np = np; | |
1808 | ap->id = id; | |
1809 | strncpy(ap->stem, stem, stem_len); | |
1810 | ap->stem[stem_len] = 0; | |
1811 | list_add_tail(&ap->link, &aliases_lookup); | |
1812 | pr_debug("adding DT alias:%s: stem=%s id=%i node=%s\n", | |
1813 | ap->alias, ap->stem, ap->id, of_node_full_name(np)); | |
1814 | } | |
1815 | ||
1816 | /** | |
1817 | * of_alias_scan - Scan all properties of 'aliases' node | |
1818 | * | |
1819 | * The function scans all the properties of 'aliases' node and populate | |
1820 | * the the global lookup table with the properties. It returns the | |
1821 | * number of alias_prop found, or error code in error case. | |
1822 | * | |
1823 | * @dt_alloc: An allocator that provides a virtual address to memory | |
1824 | * for the resulting tree | |
1825 | */ | |
1826 | void of_alias_scan(void * (*dt_alloc)(u64 size, u64 align)) | |
1827 | { | |
1828 | struct property *pp; | |
1829 | ||
1830 | of_aliases = of_find_node_by_path("/aliases"); | |
1831 | of_chosen = of_find_node_by_path("/chosen"); | |
1832 | if (of_chosen == NULL) | |
1833 | of_chosen = of_find_node_by_path("/chosen@0"); | |
1834 | ||
1835 | if (of_chosen) { | |
1836 | /* linux,stdout-path and /aliases/stdout are for legacy compatibility */ | |
1837 | const char *name = of_get_property(of_chosen, "stdout-path", NULL); | |
1838 | if (!name) | |
1839 | name = of_get_property(of_chosen, "linux,stdout-path", NULL); | |
1840 | if (IS_ENABLED(CONFIG_PPC) && !name) | |
1841 | name = of_get_property(of_aliases, "stdout", NULL); | |
1842 | if (name) | |
1843 | of_stdout = of_find_node_by_path(name); | |
1844 | } | |
1845 | ||
1846 | if (!of_aliases) | |
1847 | return; | |
1848 | ||
1849 | for_each_property_of_node(of_aliases, pp) { | |
1850 | const char *start = pp->name; | |
1851 | const char *end = start + strlen(start); | |
1852 | struct device_node *np; | |
1853 | struct alias_prop *ap; | |
1854 | int id, len; | |
1855 | ||
1856 | /* Skip those we do not want to proceed */ | |
1857 | if (!strcmp(pp->name, "name") || | |
1858 | !strcmp(pp->name, "phandle") || | |
1859 | !strcmp(pp->name, "linux,phandle")) | |
1860 | continue; | |
1861 | ||
1862 | np = of_find_node_by_path(pp->value); | |
1863 | if (!np) | |
1864 | continue; | |
1865 | ||
1866 | /* walk the alias backwards to extract the id and work out | |
1867 | * the 'stem' string */ | |
1868 | while (isdigit(*(end-1)) && end > start) | |
1869 | end--; | |
1870 | len = end - start; | |
1871 | ||
1872 | if (kstrtoint(end, 10, &id) < 0) | |
1873 | continue; | |
1874 | ||
1875 | /* Allocate an alias_prop with enough space for the stem */ | |
1876 | ap = dt_alloc(sizeof(*ap) + len + 1, 4); | |
1877 | if (!ap) | |
1878 | continue; | |
1879 | memset(ap, 0, sizeof(*ap) + len + 1); | |
1880 | ap->alias = start; | |
1881 | of_alias_add(ap, np, id, start, len); | |
1882 | } | |
1883 | } | |
1884 | ||
1885 | /** | |
1886 | * of_alias_get_id - Get alias id for the given device_node | |
1887 | * @np: Pointer to the given device_node | |
1888 | * @stem: Alias stem of the given device_node | |
1889 | * | |
1890 | * The function travels the lookup table to get the alias id for the given | |
1891 | * device_node and alias stem. It returns the alias id if found. | |
1892 | */ | |
1893 | int of_alias_get_id(struct device_node *np, const char *stem) | |
1894 | { | |
1895 | struct alias_prop *app; | |
1896 | int id = -ENODEV; | |
1897 | ||
1898 | mutex_lock(&of_mutex); | |
1899 | list_for_each_entry(app, &aliases_lookup, link) { | |
1900 | if (strcmp(app->stem, stem) != 0) | |
1901 | continue; | |
1902 | ||
1903 | if (np == app->np) { | |
1904 | id = app->id; | |
1905 | break; | |
1906 | } | |
1907 | } | |
1908 | mutex_unlock(&of_mutex); | |
1909 | ||
1910 | return id; | |
1911 | } | |
1912 | EXPORT_SYMBOL_GPL(of_alias_get_id); | |
1913 | ||
1914 | const __be32 *of_prop_next_u32(struct property *prop, const __be32 *cur, | |
1915 | u32 *pu) | |
1916 | { | |
1917 | const void *curv = cur; | |
1918 | ||
1919 | if (!prop) | |
1920 | return NULL; | |
1921 | ||
1922 | if (!cur) { | |
1923 | curv = prop->value; | |
1924 | goto out_val; | |
1925 | } | |
1926 | ||
1927 | curv += sizeof(*cur); | |
1928 | if (curv >= prop->value + prop->length) | |
1929 | return NULL; | |
1930 | ||
1931 | out_val: | |
1932 | *pu = be32_to_cpup(curv); | |
1933 | return curv; | |
1934 | } | |
1935 | EXPORT_SYMBOL_GPL(of_prop_next_u32); | |
1936 | ||
1937 | const char *of_prop_next_string(struct property *prop, const char *cur) | |
1938 | { | |
1939 | const void *curv = cur; | |
1940 | ||
1941 | if (!prop) | |
1942 | return NULL; | |
1943 | ||
1944 | if (!cur) | |
1945 | return prop->value; | |
1946 | ||
1947 | curv += strlen(cur) + 1; | |
1948 | if (curv >= prop->value + prop->length) | |
1949 | return NULL; | |
1950 | ||
1951 | return curv; | |
1952 | } | |
1953 | EXPORT_SYMBOL_GPL(of_prop_next_string); | |
1954 | ||
1955 | /** | |
1956 | * of_console_check() - Test and setup console for DT setup | |
1957 | * @dn - Pointer to device node | |
1958 | * @name - Name to use for preferred console without index. ex. "ttyS" | |
1959 | * @index - Index to use for preferred console. | |
1960 | * | |
1961 | * Check if the given device node matches the stdout-path property in the | |
1962 | * /chosen node. If it does then register it as the preferred console and return | |
1963 | * TRUE. Otherwise return FALSE. | |
1964 | */ | |
1965 | bool of_console_check(struct device_node *dn, char *name, int index) | |
1966 | { | |
1967 | if (!dn || dn != of_stdout || console_set_on_cmdline) | |
1968 | return false; | |
1969 | return !add_preferred_console(name, index, NULL); | |
1970 | } | |
1971 | EXPORT_SYMBOL_GPL(of_console_check); | |
1972 | ||
1973 | /** | |
1974 | * of_find_next_cache_node - Find a node's subsidiary cache | |
1975 | * @np: node of type "cpu" or "cache" | |
1976 | * | |
1977 | * Returns a node pointer with refcount incremented, use | |
1978 | * of_node_put() on it when done. Caller should hold a reference | |
1979 | * to np. | |
1980 | */ | |
1981 | struct device_node *of_find_next_cache_node(const struct device_node *np) | |
1982 | { | |
1983 | struct device_node *child; | |
1984 | const phandle *handle; | |
1985 | ||
1986 | handle = of_get_property(np, "l2-cache", NULL); | |
1987 | if (!handle) | |
1988 | handle = of_get_property(np, "next-level-cache", NULL); | |
1989 | ||
1990 | if (handle) | |
1991 | return of_find_node_by_phandle(be32_to_cpup(handle)); | |
1992 | ||
1993 | /* OF on pmac has nodes instead of properties named "l2-cache" | |
1994 | * beneath CPU nodes. | |
1995 | */ | |
1996 | if (!strcmp(np->type, "cpu")) | |
1997 | for_each_child_of_node(np, child) | |
1998 | if (!strcmp(child->type, "cache")) | |
1999 | return child; | |
2000 | ||
2001 | return NULL; | |
2002 | } | |
2003 | ||
2004 | /** | |
2005 | * of_graph_parse_endpoint() - parse common endpoint node properties | |
2006 | * @node: pointer to endpoint device_node | |
2007 | * @endpoint: pointer to the OF endpoint data structure | |
2008 | * | |
2009 | * The caller should hold a reference to @node. | |
2010 | */ | |
2011 | int of_graph_parse_endpoint(const struct device_node *node, | |
2012 | struct of_endpoint *endpoint) | |
2013 | { | |
2014 | struct device_node *port_node = of_get_parent(node); | |
2015 | ||
2016 | WARN_ONCE(!port_node, "%s(): endpoint %s has no parent node\n", | |
2017 | __func__, node->full_name); | |
2018 | ||
2019 | memset(endpoint, 0, sizeof(*endpoint)); | |
2020 | ||
2021 | endpoint->local_node = node; | |
2022 | /* | |
2023 | * It doesn't matter whether the two calls below succeed. | |
2024 | * If they don't then the default value 0 is used. | |
2025 | */ | |
2026 | of_property_read_u32(port_node, "reg", &endpoint->port); | |
2027 | of_property_read_u32(node, "reg", &endpoint->id); | |
2028 | ||
2029 | of_node_put(port_node); | |
2030 | ||
2031 | return 0; | |
2032 | } | |
2033 | EXPORT_SYMBOL(of_graph_parse_endpoint); | |
2034 | ||
2035 | /** | |
2036 | * of_graph_get_next_endpoint() - get next endpoint node | |
2037 | * @parent: pointer to the parent device node | |
2038 | * @prev: previous endpoint node, or NULL to get first | |
2039 | * | |
2040 | * Return: An 'endpoint' node pointer with refcount incremented. Refcount | |
2041 | * of the passed @prev node is not decremented, the caller have to use | |
2042 | * of_node_put() on it when done. | |
2043 | */ | |
2044 | struct device_node *of_graph_get_next_endpoint(const struct device_node *parent, | |
2045 | struct device_node *prev) | |
2046 | { | |
2047 | struct device_node *endpoint; | |
2048 | struct device_node *port; | |
2049 | ||
2050 | if (!parent) | |
2051 | return NULL; | |
2052 | ||
2053 | /* | |
2054 | * Start by locating the port node. If no previous endpoint is specified | |
2055 | * search for the first port node, otherwise get the previous endpoint | |
2056 | * parent port node. | |
2057 | */ | |
2058 | if (!prev) { | |
2059 | struct device_node *node; | |
2060 | ||
2061 | node = of_get_child_by_name(parent, "ports"); | |
2062 | if (node) | |
2063 | parent = node; | |
2064 | ||
2065 | port = of_get_child_by_name(parent, "port"); | |
2066 | of_node_put(node); | |
2067 | ||
2068 | if (!port) { | |
2069 | pr_err("%s(): no port node found in %s\n", | |
2070 | __func__, parent->full_name); | |
2071 | return NULL; | |
2072 | } | |
2073 | } else { | |
2074 | port = of_get_parent(prev); | |
2075 | if (WARN_ONCE(!port, "%s(): endpoint %s has no parent node\n", | |
2076 | __func__, prev->full_name)) | |
2077 | return NULL; | |
2078 | ||
2079 | /* | |
2080 | * Avoid dropping prev node refcount to 0 when getting the next | |
2081 | * child below. | |
2082 | */ | |
2083 | of_node_get(prev); | |
2084 | } | |
2085 | ||
2086 | while (1) { | |
2087 | /* | |
2088 | * Now that we have a port node, get the next endpoint by | |
2089 | * getting the next child. If the previous endpoint is NULL this | |
2090 | * will return the first child. | |
2091 | */ | |
2092 | endpoint = of_get_next_child(port, prev); | |
2093 | if (endpoint) { | |
2094 | of_node_put(port); | |
2095 | return endpoint; | |
2096 | } | |
2097 | ||
2098 | /* No more endpoints under this port, try the next one. */ | |
2099 | prev = NULL; | |
2100 | ||
2101 | do { | |
2102 | port = of_get_next_child(parent, port); | |
2103 | if (!port) | |
2104 | return NULL; | |
2105 | } while (of_node_cmp(port->name, "port")); | |
2106 | } | |
2107 | } | |
2108 | EXPORT_SYMBOL(of_graph_get_next_endpoint); | |
2109 | ||
2110 | /** | |
2111 | * of_graph_get_remote_port_parent() - get remote port's parent node | |
2112 | * @node: pointer to a local endpoint device_node | |
2113 | * | |
2114 | * Return: Remote device node associated with remote endpoint node linked | |
2115 | * to @node. Use of_node_put() on it when done. | |
2116 | */ | |
2117 | struct device_node *of_graph_get_remote_port_parent( | |
2118 | const struct device_node *node) | |
2119 | { | |
2120 | struct device_node *np; | |
2121 | unsigned int depth; | |
2122 | ||
2123 | /* Get remote endpoint node. */ | |
2124 | np = of_parse_phandle(node, "remote-endpoint", 0); | |
2125 | ||
2126 | /* Walk 3 levels up only if there is 'ports' node. */ | |
2127 | for (depth = 3; depth && np; depth--) { | |
2128 | np = of_get_next_parent(np); | |
2129 | if (depth == 2 && of_node_cmp(np->name, "ports")) | |
2130 | break; | |
2131 | } | |
2132 | return np; | |
2133 | } | |
2134 | EXPORT_SYMBOL(of_graph_get_remote_port_parent); | |
2135 | ||
2136 | /** | |
2137 | * of_graph_get_remote_port() - get remote port node | |
2138 | * @node: pointer to a local endpoint device_node | |
2139 | * | |
2140 | * Return: Remote port node associated with remote endpoint node linked | |
2141 | * to @node. Use of_node_put() on it when done. | |
2142 | */ | |
2143 | struct device_node *of_graph_get_remote_port(const struct device_node *node) | |
2144 | { | |
2145 | struct device_node *np; | |
2146 | ||
2147 | /* Get remote endpoint node. */ | |
2148 | np = of_parse_phandle(node, "remote-endpoint", 0); | |
2149 | if (!np) | |
2150 | return NULL; | |
2151 | return of_get_next_parent(np); | |
2152 | } | |
2153 | EXPORT_SYMBOL(of_graph_get_remote_port); |