]>
Commit | Line | Data |
---|---|---|
6afc0dc3 GL |
1 | /* |
2 | * Support for dynamic device trees. | |
3 | * | |
4 | * On some platforms, the device tree can be manipulated at runtime. | |
5 | * The routines in this section support adding, removing and changing | |
6 | * device tree nodes. | |
7 | */ | |
8 | ||
606ad42a RH |
9 | #define pr_fmt(fmt) "OF: " fmt |
10 | ||
6afc0dc3 GL |
11 | #include <linux/of.h> |
12 | #include <linux/spinlock.h> | |
13 | #include <linux/slab.h> | |
14 | #include <linux/string.h> | |
15 | #include <linux/proc_fs.h> | |
16 | ||
17 | #include "of_private.h" | |
18 | ||
19 | /** | |
20 | * of_node_get() - Increment refcount of a node | |
21 | * @node: Node to inc refcount, NULL is supported to simplify writing of | |
22 | * callers | |
23 | * | |
24 | * Returns node. | |
25 | */ | |
26 | struct device_node *of_node_get(struct device_node *node) | |
27 | { | |
28 | if (node) | |
29 | kobject_get(&node->kobj); | |
30 | return node; | |
31 | } | |
32 | EXPORT_SYMBOL(of_node_get); | |
33 | ||
34 | /** | |
35 | * of_node_put() - Decrement refcount of a node | |
36 | * @node: Node to dec refcount, NULL is supported to simplify writing of | |
37 | * callers | |
38 | */ | |
39 | void of_node_put(struct device_node *node) | |
40 | { | |
41 | if (node) | |
42 | kobject_put(&node->kobj); | |
43 | } | |
44 | EXPORT_SYMBOL(of_node_put); | |
45 | ||
8a2b22a2 | 46 | void __of_detach_node_sysfs(struct device_node *np) |
6afc0dc3 GL |
47 | { |
48 | struct property *pp; | |
49 | ||
ef69d740 GM |
50 | if (!IS_ENABLED(CONFIG_SYSFS)) |
51 | return; | |
52 | ||
6afc0dc3 | 53 | BUG_ON(!of_node_is_initialized(np)); |
8a2b22a2 GL |
54 | if (!of_kset) |
55 | return; | |
6afc0dc3 GL |
56 | |
57 | /* only remove properties if on sysfs */ | |
58 | if (of_node_is_attached(np)) { | |
59 | for_each_property_of_node(np, pp) | |
d9fc8807 | 60 | __of_sysfs_remove_bin_file(np, pp); |
6afc0dc3 GL |
61 | kobject_del(&np->kobj); |
62 | } | |
63 | ||
64 | /* finally remove the kobj_init ref */ | |
65 | of_node_put(np); | |
66 | } | |
67 | ||
68 | static BLOCKING_NOTIFIER_HEAD(of_reconfig_chain); | |
69 | ||
70 | int of_reconfig_notifier_register(struct notifier_block *nb) | |
71 | { | |
72 | return blocking_notifier_chain_register(&of_reconfig_chain, nb); | |
73 | } | |
74 | EXPORT_SYMBOL_GPL(of_reconfig_notifier_register); | |
75 | ||
76 | int of_reconfig_notifier_unregister(struct notifier_block *nb) | |
77 | { | |
78 | return blocking_notifier_chain_unregister(&of_reconfig_chain, nb); | |
79 | } | |
80 | EXPORT_SYMBOL_GPL(of_reconfig_notifier_unregister); | |
81 | ||
00aa3720 GL |
82 | #ifdef DEBUG |
83 | const char *action_names[] = { | |
84 | [OF_RECONFIG_ATTACH_NODE] = "ATTACH_NODE", | |
85 | [OF_RECONFIG_DETACH_NODE] = "DETACH_NODE", | |
86 | [OF_RECONFIG_ADD_PROPERTY] = "ADD_PROPERTY", | |
87 | [OF_RECONFIG_REMOVE_PROPERTY] = "REMOVE_PROPERTY", | |
88 | [OF_RECONFIG_UPDATE_PROPERTY] = "UPDATE_PROPERTY", | |
89 | }; | |
90 | #endif | |
91 | ||
f5242e5a | 92 | int of_reconfig_notify(unsigned long action, struct of_reconfig_data *p) |
6afc0dc3 GL |
93 | { |
94 | int rc; | |
00aa3720 | 95 | #ifdef DEBUG |
f5242e5a | 96 | struct of_reconfig_data *pr = p; |
00aa3720 GL |
97 | |
98 | switch (action) { | |
99 | case OF_RECONFIG_ATTACH_NODE: | |
100 | case OF_RECONFIG_DETACH_NODE: | |
0d638a07 RH |
101 | pr_debug("notify %-15s %pOF\n", action_names[action], |
102 | pr->dn); | |
00aa3720 GL |
103 | break; |
104 | case OF_RECONFIG_ADD_PROPERTY: | |
105 | case OF_RECONFIG_REMOVE_PROPERTY: | |
106 | case OF_RECONFIG_UPDATE_PROPERTY: | |
0d638a07 RH |
107 | pr_debug("notify %-15s %pOF:%s\n", action_names[action], |
108 | pr->dn, pr->prop->name); | |
00aa3720 | 109 | break; |
6afc0dc3 | 110 | |
00aa3720 GL |
111 | } |
112 | #endif | |
6afc0dc3 GL |
113 | rc = blocking_notifier_call_chain(&of_reconfig_chain, action, p); |
114 | return notifier_to_errno(rc); | |
115 | } | |
116 | ||
b53a2340 PA |
117 | /* |
118 | * of_reconfig_get_state_change() - Returns new state of device | |
119 | * @action - action of the of notifier | |
120 | * @arg - argument of the of notifier | |
121 | * | |
122 | * Returns the new state of a device based on the notifier used. | |
123 | * Returns 0 on device going from enabled to disabled, 1 on device | |
124 | * going from disabled to enabled and -1 on no change. | |
125 | */ | |
f5242e5a | 126 | int of_reconfig_get_state_change(unsigned long action, struct of_reconfig_data *pr) |
b53a2340 | 127 | { |
f5242e5a | 128 | struct property *prop, *old_prop = NULL; |
b53a2340 PA |
129 | int is_status, status_state, old_status_state, prev_state, new_state; |
130 | ||
131 | /* figure out if a device should be created or destroyed */ | |
b53a2340 PA |
132 | switch (action) { |
133 | case OF_RECONFIG_ATTACH_NODE: | |
134 | case OF_RECONFIG_DETACH_NODE: | |
f5242e5a | 135 | prop = of_find_property(pr->dn, "status", NULL); |
b53a2340 PA |
136 | break; |
137 | case OF_RECONFIG_ADD_PROPERTY: | |
138 | case OF_RECONFIG_REMOVE_PROPERTY: | |
b53a2340 PA |
139 | prop = pr->prop; |
140 | break; | |
141 | case OF_RECONFIG_UPDATE_PROPERTY: | |
b53a2340 PA |
142 | prop = pr->prop; |
143 | old_prop = pr->old_prop; | |
144 | break; | |
145 | default: | |
146 | return OF_RECONFIG_NO_CHANGE; | |
147 | } | |
148 | ||
149 | is_status = 0; | |
150 | status_state = -1; | |
151 | old_status_state = -1; | |
152 | prev_state = -1; | |
153 | new_state = -1; | |
154 | ||
155 | if (prop && !strcmp(prop->name, "status")) { | |
156 | is_status = 1; | |
157 | status_state = !strcmp(prop->value, "okay") || | |
158 | !strcmp(prop->value, "ok"); | |
159 | if (old_prop) | |
160 | old_status_state = !strcmp(old_prop->value, "okay") || | |
161 | !strcmp(old_prop->value, "ok"); | |
162 | } | |
163 | ||
164 | switch (action) { | |
165 | case OF_RECONFIG_ATTACH_NODE: | |
166 | prev_state = 0; | |
167 | /* -1 & 0 status either missing or okay */ | |
168 | new_state = status_state != 0; | |
169 | break; | |
170 | case OF_RECONFIG_DETACH_NODE: | |
171 | /* -1 & 0 status either missing or okay */ | |
172 | prev_state = status_state != 0; | |
173 | new_state = 0; | |
174 | break; | |
175 | case OF_RECONFIG_ADD_PROPERTY: | |
176 | if (is_status) { | |
177 | /* no status property -> enabled (legacy) */ | |
178 | prev_state = 1; | |
179 | new_state = status_state; | |
180 | } | |
181 | break; | |
182 | case OF_RECONFIG_REMOVE_PROPERTY: | |
183 | if (is_status) { | |
184 | prev_state = status_state; | |
185 | /* no status property -> enabled (legacy) */ | |
186 | new_state = 1; | |
187 | } | |
188 | break; | |
189 | case OF_RECONFIG_UPDATE_PROPERTY: | |
190 | if (is_status) { | |
191 | prev_state = old_status_state != 0; | |
192 | new_state = status_state != 0; | |
193 | } | |
194 | break; | |
195 | } | |
196 | ||
197 | if (prev_state == new_state) | |
198 | return OF_RECONFIG_NO_CHANGE; | |
199 | ||
200 | return new_state ? OF_RECONFIG_CHANGE_ADD : OF_RECONFIG_CHANGE_REMOVE; | |
201 | } | |
202 | EXPORT_SYMBOL_GPL(of_reconfig_get_state_change); | |
203 | ||
6afc0dc3 | 204 | int of_property_notify(int action, struct device_node *np, |
259092a3 | 205 | struct property *prop, struct property *oldprop) |
6afc0dc3 | 206 | { |
f5242e5a | 207 | struct of_reconfig_data pr; |
6afc0dc3 GL |
208 | |
209 | /* only call notifiers if the node is attached */ | |
210 | if (!of_node_is_attached(np)) | |
211 | return 0; | |
212 | ||
213 | pr.dn = np; | |
214 | pr.prop = prop; | |
259092a3 | 215 | pr.old_prop = oldprop; |
6afc0dc3 GL |
216 | return of_reconfig_notify(action, &pr); |
217 | } | |
218 | ||
24996951 | 219 | static void __of_attach_node(struct device_node *np) |
d8c50088 | 220 | { |
a25095d4 GL |
221 | const __be32 *phandle; |
222 | int sz; | |
223 | ||
224 | np->name = __of_get_property(np, "name", NULL) ? : "<NULL>"; | |
225 | np->type = __of_get_property(np, "device_type", NULL) ? : "<NULL>"; | |
226 | ||
227 | phandle = __of_get_property(np, "phandle", &sz); | |
228 | if (!phandle) | |
229 | phandle = __of_get_property(np, "linux,phandle", &sz); | |
f76502aa | 230 | if (IS_ENABLED(CONFIG_PPC_PSERIES) && !phandle) |
a25095d4 GL |
231 | phandle = __of_get_property(np, "ibm,phandle", &sz); |
232 | np->phandle = (phandle && (sz >= 4)) ? be32_to_cpup(phandle) : 0; | |
233 | ||
6162dbe4 | 234 | np->child = NULL; |
d8c50088 | 235 | np->sibling = np->parent->child; |
d8c50088 PA |
236 | np->parent->child = np; |
237 | of_node_clear_flag(np, OF_DETACHED); | |
238 | } | |
239 | ||
6afc0dc3 GL |
240 | /** |
241 | * of_attach_node() - Plug a device node into the tree and global list. | |
242 | */ | |
243 | int of_attach_node(struct device_node *np) | |
244 | { | |
f5242e5a | 245 | struct of_reconfig_data rd; |
6afc0dc3 | 246 | unsigned long flags; |
6afc0dc3 | 247 | |
f5242e5a GL |
248 | memset(&rd, 0, sizeof(rd)); |
249 | rd.dn = np; | |
250 | ||
8a2b22a2 | 251 | mutex_lock(&of_mutex); |
6afc0dc3 | 252 | raw_spin_lock_irqsave(&devtree_lock, flags); |
d8c50088 | 253 | __of_attach_node(np); |
6afc0dc3 GL |
254 | raw_spin_unlock_irqrestore(&devtree_lock, flags); |
255 | ||
8a2b22a2 GL |
256 | __of_attach_node_sysfs(np); |
257 | mutex_unlock(&of_mutex); | |
259092a3 | 258 | |
f5242e5a | 259 | of_reconfig_notify(OF_RECONFIG_ATTACH_NODE, &rd); |
259092a3 | 260 | |
6afc0dc3 GL |
261 | return 0; |
262 | } | |
263 | ||
d8c50088 | 264 | void __of_detach_node(struct device_node *np) |
6afc0dc3 GL |
265 | { |
266 | struct device_node *parent; | |
6afc0dc3 | 267 | |
d8c50088 PA |
268 | if (WARN_ON(of_node_check_flag(np, OF_DETACHED))) |
269 | return; | |
6afc0dc3 GL |
270 | |
271 | parent = np->parent; | |
d8c50088 PA |
272 | if (WARN_ON(!parent)) |
273 | return; | |
6afc0dc3 | 274 | |
6afc0dc3 GL |
275 | if (parent->child == np) |
276 | parent->child = np->sibling; | |
277 | else { | |
278 | struct device_node *prevsib; | |
279 | for (prevsib = np->parent->child; | |
280 | prevsib->sibling != np; | |
281 | prevsib = prevsib->sibling) | |
282 | ; | |
283 | prevsib->sibling = np->sibling; | |
284 | } | |
285 | ||
286 | of_node_set_flag(np, OF_DETACHED); | |
d8c50088 PA |
287 | } |
288 | ||
289 | /** | |
290 | * of_detach_node() - "Unplug" a node from the device tree. | |
291 | * | |
292 | * The caller must hold a reference to the node. The memory associated with | |
293 | * the node is not freed until its refcount goes to zero. | |
294 | */ | |
295 | int of_detach_node(struct device_node *np) | |
296 | { | |
f5242e5a | 297 | struct of_reconfig_data rd; |
d8c50088 PA |
298 | unsigned long flags; |
299 | int rc = 0; | |
300 | ||
f5242e5a GL |
301 | memset(&rd, 0, sizeof(rd)); |
302 | rd.dn = np; | |
303 | ||
8a2b22a2 | 304 | mutex_lock(&of_mutex); |
d8c50088 PA |
305 | raw_spin_lock_irqsave(&devtree_lock, flags); |
306 | __of_detach_node(np); | |
6afc0dc3 GL |
307 | raw_spin_unlock_irqrestore(&devtree_lock, flags); |
308 | ||
8a2b22a2 GL |
309 | __of_detach_node_sysfs(np); |
310 | mutex_unlock(&of_mutex); | |
259092a3 | 311 | |
f5242e5a | 312 | of_reconfig_notify(OF_RECONFIG_DETACH_NODE, &rd); |
259092a3 | 313 | |
6afc0dc3 GL |
314 | return rc; |
315 | } | |
bb91f923 | 316 | EXPORT_SYMBOL_GPL(of_detach_node); |
6afc0dc3 GL |
317 | |
318 | /** | |
319 | * of_node_release() - release a dynamically allocated node | |
320 | * @kref: kref element of the node to be released | |
321 | * | |
322 | * In of_node_put() this function is passed to kref_put() as the destructor. | |
323 | */ | |
324 | void of_node_release(struct kobject *kobj) | |
325 | { | |
326 | struct device_node *node = kobj_to_device_node(kobj); | |
327 | struct property *prop = node->properties; | |
328 | ||
329 | /* We should never be releasing nodes that haven't been detached. */ | |
330 | if (!of_node_check_flag(node, OF_DETACHED)) { | |
0d638a07 | 331 | pr_err("ERROR: Bad of_node_put() on %pOF\n", node); |
6afc0dc3 GL |
332 | dump_stack(); |
333 | return; | |
334 | } | |
6afc0dc3 GL |
335 | if (!of_node_check_flag(node, OF_DYNAMIC)) |
336 | return; | |
337 | ||
338 | while (prop) { | |
339 | struct property *next = prop->next; | |
340 | kfree(prop->name); | |
341 | kfree(prop->value); | |
342 | kfree(prop); | |
343 | prop = next; | |
344 | ||
345 | if (!prop) { | |
346 | prop = node->deadprops; | |
347 | node->deadprops = NULL; | |
348 | } | |
349 | } | |
350 | kfree(node->full_name); | |
351 | kfree(node->data); | |
352 | kfree(node); | |
353 | } | |
69843396 PA |
354 | |
355 | /** | |
356 | * __of_prop_dup - Copy a property dynamically. | |
357 | * @prop: Property to copy | |
358 | * @allocflags: Allocation flags (typically pass GFP_KERNEL) | |
359 | * | |
360 | * Copy a property by dynamically allocating the memory of both the | |
27b3383a | 361 | * property structure and the property name & contents. The property's |
69843396 PA |
362 | * flags have the OF_DYNAMIC bit set so that we can differentiate between |
363 | * dynamically allocated properties and not. | |
364 | * Returns the newly allocated property or NULL on out of memory error. | |
365 | */ | |
366 | struct property *__of_prop_dup(const struct property *prop, gfp_t allocflags) | |
367 | { | |
368 | struct property *new; | |
369 | ||
370 | new = kzalloc(sizeof(*new), allocflags); | |
371 | if (!new) | |
372 | return NULL; | |
373 | ||
374 | /* | |
375 | * NOTE: There is no check for zero length value. | |
b6ae5dc5 | 376 | * In case of a boolean property, this will allocate a value |
69843396 PA |
377 | * of zero bytes. We do this to work around the use |
378 | * of of_get_property() calls on boolean values. | |
379 | */ | |
380 | new->name = kstrdup(prop->name, allocflags); | |
381 | new->value = kmemdup(prop->value, prop->length, allocflags); | |
382 | new->length = prop->length; | |
383 | if (!new->name || !new->value) | |
384 | goto err_free; | |
385 | ||
386 | /* mark the property as dynamic */ | |
387 | of_property_set_flag(new, OF_DYNAMIC); | |
388 | ||
389 | return new; | |
390 | ||
391 | err_free: | |
392 | kfree(new->name); | |
393 | kfree(new->value); | |
394 | kfree(new); | |
395 | return NULL; | |
396 | } | |
397 | ||
398 | /** | |
e5179581 GL |
399 | * __of_node_dup() - Duplicate or create an empty device node dynamically. |
400 | * @fmt: Format string (plus vargs) for new full name of the device node | |
69843396 | 401 | * |
e5179581 GL |
402 | * Create an device tree node, either by duplicating an empty node or by allocating |
403 | * an empty one suitable for further modification. The node data are | |
404 | * dynamically allocated and all the node flags have the OF_DYNAMIC & | |
405 | * OF_DETACHED bits set. Returns the newly allocated node or NULL on out of | |
406 | * memory error. | |
69843396 | 407 | */ |
e5179581 | 408 | struct device_node *__of_node_dup(const struct device_node *np, const char *fmt, ...) |
69843396 | 409 | { |
ef8bbd73 | 410 | va_list vargs; |
69843396 PA |
411 | struct device_node *node; |
412 | ||
ef8bbd73 | 413 | node = kzalloc(sizeof(*node), GFP_KERNEL); |
69843396 PA |
414 | if (!node) |
415 | return NULL; | |
ef8bbd73 GL |
416 | va_start(vargs, fmt); |
417 | node->full_name = kvasprintf(GFP_KERNEL, fmt, vargs); | |
418 | va_end(vargs); | |
e5179581 GL |
419 | if (!node->full_name) { |
420 | kfree(node); | |
421 | return NULL; | |
422 | } | |
69843396 | 423 | |
ef8bbd73 GL |
424 | of_node_set_flag(node, OF_DYNAMIC); |
425 | of_node_set_flag(node, OF_DETACHED); | |
69843396 PA |
426 | of_node_init(node); |
427 | ||
e5179581 GL |
428 | /* Iterate over and duplicate all properties */ |
429 | if (np) { | |
430 | struct property *pp, *new_pp; | |
431 | for_each_property_of_node(np, pp) { | |
432 | new_pp = __of_prop_dup(pp, GFP_KERNEL); | |
433 | if (!new_pp) | |
434 | goto err_prop; | |
435 | if (__of_add_property(node, new_pp)) { | |
436 | kfree(new_pp->name); | |
437 | kfree(new_pp->value); | |
438 | kfree(new_pp); | |
439 | goto err_prop; | |
440 | } | |
441 | } | |
442 | } | |
69843396 PA |
443 | return node; |
444 | ||
e5179581 GL |
445 | err_prop: |
446 | of_node_put(node); /* Frees the node and properties */ | |
69843396 PA |
447 | return NULL; |
448 | } | |
201c910b PA |
449 | |
450 | static void __of_changeset_entry_destroy(struct of_changeset_entry *ce) | |
451 | { | |
452 | of_node_put(ce->np); | |
453 | list_del(&ce->node); | |
454 | kfree(ce); | |
455 | } | |
456 | ||
457 | #ifdef DEBUG | |
458 | static void __of_changeset_entry_dump(struct of_changeset_entry *ce) | |
459 | { | |
460 | switch (ce->action) { | |
461 | case OF_RECONFIG_ADD_PROPERTY: | |
201c910b | 462 | case OF_RECONFIG_REMOVE_PROPERTY: |
201c910b | 463 | case OF_RECONFIG_UPDATE_PROPERTY: |
0d638a07 RH |
464 | pr_debug("cset<%p> %-15s %pOF/%s\n", ce, action_names[ce->action], |
465 | ce->np, ce->prop->name); | |
201c910b PA |
466 | break; |
467 | case OF_RECONFIG_ATTACH_NODE: | |
201c910b | 468 | case OF_RECONFIG_DETACH_NODE: |
0d638a07 RH |
469 | pr_debug("cset<%p> %-15s %pOF\n", ce, action_names[ce->action], |
470 | ce->np); | |
201c910b PA |
471 | break; |
472 | } | |
473 | } | |
474 | #else | |
475 | static inline void __of_changeset_entry_dump(struct of_changeset_entry *ce) | |
476 | { | |
477 | /* empty */ | |
478 | } | |
479 | #endif | |
480 | ||
481 | static void __of_changeset_entry_invert(struct of_changeset_entry *ce, | |
482 | struct of_changeset_entry *rce) | |
483 | { | |
484 | memcpy(rce, ce, sizeof(*rce)); | |
485 | ||
486 | switch (ce->action) { | |
487 | case OF_RECONFIG_ATTACH_NODE: | |
488 | rce->action = OF_RECONFIG_DETACH_NODE; | |
489 | break; | |
490 | case OF_RECONFIG_DETACH_NODE: | |
491 | rce->action = OF_RECONFIG_ATTACH_NODE; | |
492 | break; | |
493 | case OF_RECONFIG_ADD_PROPERTY: | |
494 | rce->action = OF_RECONFIG_REMOVE_PROPERTY; | |
495 | break; | |
496 | case OF_RECONFIG_REMOVE_PROPERTY: | |
497 | rce->action = OF_RECONFIG_ADD_PROPERTY; | |
498 | break; | |
499 | case OF_RECONFIG_UPDATE_PROPERTY: | |
500 | rce->old_prop = ce->prop; | |
501 | rce->prop = ce->old_prop; | |
b9c43856 PA |
502 | /* update was used but original property did not exist */ |
503 | if (!rce->prop) { | |
504 | rce->action = OF_RECONFIG_REMOVE_PROPERTY; | |
505 | rce->prop = ce->prop; | |
506 | } | |
201c910b PA |
507 | break; |
508 | } | |
509 | } | |
510 | ||
511 | static void __of_changeset_entry_notify(struct of_changeset_entry *ce, bool revert) | |
512 | { | |
f5242e5a | 513 | struct of_reconfig_data rd; |
201c910b PA |
514 | struct of_changeset_entry ce_inverted; |
515 | int ret; | |
516 | ||
517 | if (revert) { | |
518 | __of_changeset_entry_invert(ce, &ce_inverted); | |
519 | ce = &ce_inverted; | |
520 | } | |
521 | ||
522 | switch (ce->action) { | |
523 | case OF_RECONFIG_ATTACH_NODE: | |
524 | case OF_RECONFIG_DETACH_NODE: | |
f5242e5a GL |
525 | memset(&rd, 0, sizeof(rd)); |
526 | rd.dn = ce->np; | |
527 | ret = of_reconfig_notify(ce->action, &rd); | |
201c910b PA |
528 | break; |
529 | case OF_RECONFIG_ADD_PROPERTY: | |
530 | case OF_RECONFIG_REMOVE_PROPERTY: | |
531 | case OF_RECONFIG_UPDATE_PROPERTY: | |
532 | ret = of_property_notify(ce->action, ce->np, ce->prop, ce->old_prop); | |
533 | break; | |
534 | default: | |
606ad42a | 535 | pr_err("invalid devicetree changeset action: %i\n", |
201c910b PA |
536 | (int)ce->action); |
537 | return; | |
538 | } | |
539 | ||
540 | if (ret) | |
0d638a07 | 541 | pr_err("changeset notifier error @%pOF\n", ce->np); |
201c910b PA |
542 | } |
543 | ||
544 | static int __of_changeset_entry_apply(struct of_changeset_entry *ce) | |
545 | { | |
546 | struct property *old_prop, **propp; | |
547 | unsigned long flags; | |
548 | int ret = 0; | |
549 | ||
550 | __of_changeset_entry_dump(ce); | |
551 | ||
552 | raw_spin_lock_irqsave(&devtree_lock, flags); | |
553 | switch (ce->action) { | |
554 | case OF_RECONFIG_ATTACH_NODE: | |
555 | __of_attach_node(ce->np); | |
556 | break; | |
557 | case OF_RECONFIG_DETACH_NODE: | |
558 | __of_detach_node(ce->np); | |
559 | break; | |
560 | case OF_RECONFIG_ADD_PROPERTY: | |
561 | /* If the property is in deadprops then it must be removed */ | |
562 | for (propp = &ce->np->deadprops; *propp; propp = &(*propp)->next) { | |
563 | if (*propp == ce->prop) { | |
564 | *propp = ce->prop->next; | |
565 | ce->prop->next = NULL; | |
566 | break; | |
567 | } | |
568 | } | |
569 | ||
570 | ret = __of_add_property(ce->np, ce->prop); | |
571 | if (ret) { | |
0d638a07 RH |
572 | pr_err("changeset: add_property failed @%pOF/%s\n", |
573 | ce->np, | |
201c910b PA |
574 | ce->prop->name); |
575 | break; | |
576 | } | |
577 | break; | |
578 | case OF_RECONFIG_REMOVE_PROPERTY: | |
579 | ret = __of_remove_property(ce->np, ce->prop); | |
580 | if (ret) { | |
0d638a07 RH |
581 | pr_err("changeset: remove_property failed @%pOF/%s\n", |
582 | ce->np, | |
201c910b PA |
583 | ce->prop->name); |
584 | break; | |
585 | } | |
586 | break; | |
587 | ||
588 | case OF_RECONFIG_UPDATE_PROPERTY: | |
589 | /* If the property is in deadprops then it must be removed */ | |
590 | for (propp = &ce->np->deadprops; *propp; propp = &(*propp)->next) { | |
591 | if (*propp == ce->prop) { | |
592 | *propp = ce->prop->next; | |
593 | ce->prop->next = NULL; | |
594 | break; | |
595 | } | |
596 | } | |
597 | ||
598 | ret = __of_update_property(ce->np, ce->prop, &old_prop); | |
599 | if (ret) { | |
0d638a07 RH |
600 | pr_err("changeset: update_property failed @%pOF/%s\n", |
601 | ce->np, | |
201c910b PA |
602 | ce->prop->name); |
603 | break; | |
604 | } | |
605 | break; | |
606 | default: | |
607 | ret = -EINVAL; | |
608 | } | |
609 | raw_spin_unlock_irqrestore(&devtree_lock, flags); | |
610 | ||
611 | if (ret) | |
612 | return ret; | |
613 | ||
614 | switch (ce->action) { | |
615 | case OF_RECONFIG_ATTACH_NODE: | |
616 | __of_attach_node_sysfs(ce->np); | |
617 | break; | |
618 | case OF_RECONFIG_DETACH_NODE: | |
619 | __of_detach_node_sysfs(ce->np); | |
620 | break; | |
621 | case OF_RECONFIG_ADD_PROPERTY: | |
622 | /* ignore duplicate names */ | |
623 | __of_add_property_sysfs(ce->np, ce->prop); | |
624 | break; | |
625 | case OF_RECONFIG_REMOVE_PROPERTY: | |
626 | __of_remove_property_sysfs(ce->np, ce->prop); | |
627 | break; | |
628 | case OF_RECONFIG_UPDATE_PROPERTY: | |
629 | __of_update_property_sysfs(ce->np, ce->prop, ce->old_prop); | |
630 | break; | |
631 | } | |
632 | ||
633 | return 0; | |
634 | } | |
635 | ||
636 | static inline int __of_changeset_entry_revert(struct of_changeset_entry *ce) | |
637 | { | |
638 | struct of_changeset_entry ce_inverted; | |
639 | ||
640 | __of_changeset_entry_invert(ce, &ce_inverted); | |
641 | return __of_changeset_entry_apply(&ce_inverted); | |
642 | } | |
643 | ||
644 | /** | |
645 | * of_changeset_init - Initialize a changeset for use | |
646 | * | |
647 | * @ocs: changeset pointer | |
648 | * | |
649 | * Initialize a changeset structure | |
650 | */ | |
651 | void of_changeset_init(struct of_changeset *ocs) | |
652 | { | |
653 | memset(ocs, 0, sizeof(*ocs)); | |
654 | INIT_LIST_HEAD(&ocs->entries); | |
655 | } | |
18322377 | 656 | EXPORT_SYMBOL_GPL(of_changeset_init); |
201c910b PA |
657 | |
658 | /** | |
659 | * of_changeset_destroy - Destroy a changeset | |
660 | * | |
661 | * @ocs: changeset pointer | |
662 | * | |
663 | * Destroys a changeset. Note that if a changeset is applied, | |
664 | * its changes to the tree cannot be reverted. | |
665 | */ | |
666 | void of_changeset_destroy(struct of_changeset *ocs) | |
667 | { | |
668 | struct of_changeset_entry *ce, *cen; | |
669 | ||
670 | list_for_each_entry_safe_reverse(ce, cen, &ocs->entries, node) | |
671 | __of_changeset_entry_destroy(ce); | |
672 | } | |
18322377 | 673 | EXPORT_SYMBOL_GPL(of_changeset_destroy); |
201c910b | 674 | |
18322377 | 675 | int __of_changeset_apply(struct of_changeset *ocs) |
201c910b PA |
676 | { |
677 | struct of_changeset_entry *ce; | |
678 | int ret; | |
679 | ||
680 | /* perform the rest of the work */ | |
606ad42a | 681 | pr_debug("changeset: applying...\n"); |
201c910b PA |
682 | list_for_each_entry(ce, &ocs->entries, node) { |
683 | ret = __of_changeset_entry_apply(ce); | |
684 | if (ret) { | |
606ad42a | 685 | pr_err("Error applying changeset (%d)\n", ret); |
201c910b PA |
686 | list_for_each_entry_continue_reverse(ce, &ocs->entries, node) |
687 | __of_changeset_entry_revert(ce); | |
688 | return ret; | |
689 | } | |
690 | } | |
606ad42a | 691 | pr_debug("changeset: applied, emitting notifiers.\n"); |
201c910b PA |
692 | |
693 | /* drop the global lock while emitting notifiers */ | |
694 | mutex_unlock(&of_mutex); | |
695 | list_for_each_entry(ce, &ocs->entries, node) | |
696 | __of_changeset_entry_notify(ce, 0); | |
697 | mutex_lock(&of_mutex); | |
606ad42a | 698 | pr_debug("changeset: notifiers sent.\n"); |
201c910b PA |
699 | |
700 | return 0; | |
701 | } | |
702 | ||
703 | /** | |
18322377 | 704 | * of_changeset_apply - Applies a changeset |
201c910b PA |
705 | * |
706 | * @ocs: changeset pointer | |
707 | * | |
18322377 GS |
708 | * Applies a changeset to the live tree. |
709 | * Any side-effects of live tree state changes are applied here on | |
710 | * success, like creation/destruction of devices and side-effects | |
711 | * like creation of sysfs properties and directories. | |
201c910b | 712 | * Returns 0 on success, a negative error value in case of an error. |
18322377 | 713 | * On error the partially applied effects are reverted. |
201c910b | 714 | */ |
18322377 GS |
715 | int of_changeset_apply(struct of_changeset *ocs) |
716 | { | |
717 | int ret; | |
718 | ||
719 | mutex_lock(&of_mutex); | |
720 | ret = __of_changeset_apply(ocs); | |
721 | mutex_unlock(&of_mutex); | |
722 | ||
723 | return ret; | |
724 | } | |
725 | EXPORT_SYMBOL_GPL(of_changeset_apply); | |
726 | ||
727 | int __of_changeset_revert(struct of_changeset *ocs) | |
201c910b PA |
728 | { |
729 | struct of_changeset_entry *ce; | |
730 | int ret; | |
731 | ||
606ad42a | 732 | pr_debug("changeset: reverting...\n"); |
201c910b PA |
733 | list_for_each_entry_reverse(ce, &ocs->entries, node) { |
734 | ret = __of_changeset_entry_revert(ce); | |
735 | if (ret) { | |
606ad42a | 736 | pr_err("Error reverting changeset (%d)\n", ret); |
201c910b PA |
737 | list_for_each_entry_continue(ce, &ocs->entries, node) |
738 | __of_changeset_entry_apply(ce); | |
739 | return ret; | |
740 | } | |
741 | } | |
606ad42a | 742 | pr_debug("changeset: reverted, emitting notifiers.\n"); |
201c910b PA |
743 | |
744 | /* drop the global lock while emitting notifiers */ | |
745 | mutex_unlock(&of_mutex); | |
746 | list_for_each_entry_reverse(ce, &ocs->entries, node) | |
747 | __of_changeset_entry_notify(ce, 1); | |
748 | mutex_lock(&of_mutex); | |
606ad42a | 749 | pr_debug("changeset: notifiers sent.\n"); |
201c910b PA |
750 | |
751 | return 0; | |
752 | } | |
753 | ||
18322377 GS |
754 | /** |
755 | * of_changeset_revert - Reverts an applied changeset | |
756 | * | |
757 | * @ocs: changeset pointer | |
758 | * | |
759 | * Reverts a changeset returning the state of the tree to what it | |
760 | * was before the application. | |
761 | * Any side-effects like creation/destruction of devices and | |
762 | * removal of sysfs properties and directories are applied. | |
763 | * Returns 0 on success, a negative error value in case of an error. | |
764 | */ | |
765 | int of_changeset_revert(struct of_changeset *ocs) | |
766 | { | |
767 | int ret; | |
768 | ||
769 | mutex_lock(&of_mutex); | |
770 | ret = __of_changeset_revert(ocs); | |
771 | mutex_unlock(&of_mutex); | |
772 | ||
773 | return ret; | |
774 | } | |
775 | EXPORT_SYMBOL_GPL(of_changeset_revert); | |
776 | ||
201c910b PA |
777 | /** |
778 | * of_changeset_action - Perform a changeset action | |
779 | * | |
780 | * @ocs: changeset pointer | |
781 | * @action: action to perform | |
782 | * @np: Pointer to device node | |
783 | * @prop: Pointer to property | |
784 | * | |
785 | * On action being one of: | |
786 | * + OF_RECONFIG_ATTACH_NODE | |
787 | * + OF_RECONFIG_DETACH_NODE, | |
788 | * + OF_RECONFIG_ADD_PROPERTY | |
789 | * + OF_RECONFIG_REMOVE_PROPERTY, | |
790 | * + OF_RECONFIG_UPDATE_PROPERTY | |
791 | * Returns 0 on success, a negative error value in case of an error. | |
792 | */ | |
793 | int of_changeset_action(struct of_changeset *ocs, unsigned long action, | |
794 | struct device_node *np, struct property *prop) | |
795 | { | |
796 | struct of_changeset_entry *ce; | |
797 | ||
798 | ce = kzalloc(sizeof(*ce), GFP_KERNEL); | |
606ad42a | 799 | if (!ce) |
201c910b | 800 | return -ENOMEM; |
606ad42a | 801 | |
201c910b PA |
802 | /* get a reference to the node */ |
803 | ce->action = action; | |
804 | ce->np = of_node_get(np); | |
805 | ce->prop = prop; | |
806 | ||
807 | if (action == OF_RECONFIG_UPDATE_PROPERTY && prop) | |
808 | ce->old_prop = of_find_property(np, prop->name, NULL); | |
809 | ||
810 | /* add it to the list */ | |
811 | list_add_tail(&ce->node, &ocs->entries); | |
812 | return 0; | |
813 | } | |
18322377 | 814 | EXPORT_SYMBOL_GPL(of_changeset_action); |