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1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * Copyright (C) 2006 Benjamin Herrenschmidt, IBM Corp.
4 * <benh@kernel.crashing.org>
5 * and Arnd Bergmann, IBM Corp.
6 * Merged from powerpc/kernel/of_platform.c and
7 * sparc{,64}/kernel/of_device.c by Stephen Rothwell
8 */
9
10#define pr_fmt(fmt) "OF: " fmt
11
12#include <linux/errno.h>
13#include <linux/module.h>
14#include <linux/amba/bus.h>
15#include <linux/device.h>
16#include <linux/dma-mapping.h>
17#include <linux/slab.h>
18#include <linux/of_address.h>
19#include <linux/of_device.h>
20#include <linux/of_iommu.h>
21#include <linux/of_irq.h>
22#include <linux/of_platform.h>
23#include <linux/platform_device.h>
24
25const struct of_device_id of_default_bus_match_table[] = {
26 { .compatible = "simple-bus", },
27 { .compatible = "simple-mfd", },
28 { .compatible = "isa", },
29#ifdef CONFIG_ARM_AMBA
30 { .compatible = "arm,amba-bus", },
31#endif /* CONFIG_ARM_AMBA */
32 {} /* Empty terminated list */
33};
34
35static const struct of_device_id of_skipped_node_table[] = {
36 { .compatible = "operating-points-v2", },
37 {} /* Empty terminated list */
38};
39
40/**
41 * of_find_device_by_node - Find the platform_device associated with a node
42 * @np: Pointer to device tree node
43 *
44 * Takes a reference to the embedded struct device which needs to be dropped
45 * after use.
46 *
47 * Returns platform_device pointer, or NULL if not found
48 */
49struct platform_device *of_find_device_by_node(struct device_node *np)
50{
51 struct device *dev;
52
53 dev = bus_find_device_by_of_node(&platform_bus_type, np);
54 return dev ? to_platform_device(dev) : NULL;
55}
56EXPORT_SYMBOL(of_find_device_by_node);
57
58#ifdef CONFIG_OF_ADDRESS
59/*
60 * The following routines scan a subtree and registers a device for
61 * each applicable node.
62 *
63 * Note: sparc doesn't use these routines because it has a different
64 * mechanism for creating devices from device tree nodes.
65 */
66
67/**
68 * of_device_make_bus_id - Use the device node data to assign a unique name
69 * @dev: pointer to device structure that is linked to a device tree node
70 *
71 * This routine will first try using the translated bus address to
72 * derive a unique name. If it cannot, then it will prepend names from
73 * parent nodes until a unique name can be derived.
74 */
75static void of_device_make_bus_id(struct device *dev)
76{
77 struct device_node *node = dev->of_node;
78 const __be32 *reg;
79 u64 addr;
80
81 /* Construct the name, using parent nodes if necessary to ensure uniqueness */
82 while (node->parent) {
83 /*
84 * If the address can be translated, then that is as much
85 * uniqueness as we need. Make it the first component and return
86 */
87 reg = of_get_property(node, "reg", NULL);
88 if (reg && (addr = of_translate_address(node, reg)) != OF_BAD_ADDR) {
89 dev_set_name(dev, dev_name(dev) ? "%llx.%pOFn:%s" : "%llx.%pOFn",
90 addr, node, dev_name(dev));
91 return;
92 }
93
94 /* format arguments only used if dev_name() resolves to NULL */
95 dev_set_name(dev, dev_name(dev) ? "%s:%s" : "%s",
96 kbasename(node->full_name), dev_name(dev));
97 node = node->parent;
98 }
99}
100
101/**
102 * of_device_alloc - Allocate and initialize an of_device
103 * @np: device node to assign to device
104 * @bus_id: Name to assign to the device. May be null to use default name.
105 * @parent: Parent device.
106 */
107struct platform_device *of_device_alloc(struct device_node *np,
108 const char *bus_id,
109 struct device *parent)
110{
111 struct platform_device *dev;
112 int rc, i, num_reg = 0, num_irq;
113 struct resource *res, temp_res;
114
115 dev = platform_device_alloc("", PLATFORM_DEVID_NONE);
116 if (!dev)
117 return NULL;
118
119 /* count the io and irq resources */
120 while (of_address_to_resource(np, num_reg, &temp_res) == 0)
121 num_reg++;
122 num_irq = of_irq_count(np);
123
124 /* Populate the resource table */
125 if (num_irq || num_reg) {
126 res = kcalloc(num_irq + num_reg, sizeof(*res), GFP_KERNEL);
127 if (!res) {
128 platform_device_put(dev);
129 return NULL;
130 }
131
132 dev->num_resources = num_reg + num_irq;
133 dev->resource = res;
134 for (i = 0; i < num_reg; i++, res++) {
135 rc = of_address_to_resource(np, i, res);
136 WARN_ON(rc);
137 }
138 if (of_irq_to_resource_table(np, res, num_irq) != num_irq)
139 pr_debug("not all legacy IRQ resources mapped for %pOFn\n",
140 np);
141 }
142
143 dev->dev.of_node = of_node_get(np);
144 dev->dev.fwnode = &np->fwnode;
145 dev->dev.parent = parent ? : &platform_bus;
146
147 if (bus_id)
148 dev_set_name(&dev->dev, "%s", bus_id);
149 else
150 of_device_make_bus_id(&dev->dev);
151
152 return dev;
153}
154EXPORT_SYMBOL(of_device_alloc);
155
156/**
157 * of_platform_device_create_pdata - Alloc, initialize and register an of_device
158 * @np: pointer to node to create device for
159 * @bus_id: name to assign device
160 * @platform_data: pointer to populate platform_data pointer with
161 * @parent: Linux device model parent device.
162 *
163 * Returns pointer to created platform device, or NULL if a device was not
164 * registered. Unavailable devices will not get registered.
165 */
166static struct platform_device *of_platform_device_create_pdata(
167 struct device_node *np,
168 const char *bus_id,
169 void *platform_data,
170 struct device *parent)
171{
172 struct platform_device *dev;
173
174 if (!of_device_is_available(np) ||
175 of_node_test_and_set_flag(np, OF_POPULATED))
176 return NULL;
177
178 dev = of_device_alloc(np, bus_id, parent);
179 if (!dev)
180 goto err_clear_flag;
181
182 dev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
183 if (!dev->dev.dma_mask)
184 dev->dev.dma_mask = &dev->dev.coherent_dma_mask;
185 dev->dev.bus = &platform_bus_type;
186 dev->dev.platform_data = platform_data;
187 of_msi_configure(&dev->dev, dev->dev.of_node);
188
189 if (of_device_add(dev) != 0) {
190 platform_device_put(dev);
191 goto err_clear_flag;
192 }
193
194 return dev;
195
196err_clear_flag:
197 of_node_clear_flag(np, OF_POPULATED);
198 return NULL;
199}
200
201/**
202 * of_platform_device_create - Alloc, initialize and register an of_device
203 * @np: pointer to node to create device for
204 * @bus_id: name to assign device
205 * @parent: Linux device model parent device.
206 *
207 * Returns pointer to created platform device, or NULL if a device was not
208 * registered. Unavailable devices will not get registered.
209 */
210struct platform_device *of_platform_device_create(struct device_node *np,
211 const char *bus_id,
212 struct device *parent)
213{
214 return of_platform_device_create_pdata(np, bus_id, NULL, parent);
215}
216EXPORT_SYMBOL(of_platform_device_create);
217
218#ifdef CONFIG_ARM_AMBA
219static struct amba_device *of_amba_device_create(struct device_node *node,
220 const char *bus_id,
221 void *platform_data,
222 struct device *parent)
223{
224 struct amba_device *dev;
225 const void *prop;
226 int i, ret;
227
228 pr_debug("Creating amba device %pOF\n", node);
229
230 if (!of_device_is_available(node) ||
231 of_node_test_and_set_flag(node, OF_POPULATED))
232 return NULL;
233
234 dev = amba_device_alloc(NULL, 0, 0);
235 if (!dev)
236 goto err_clear_flag;
237
238 /* AMBA devices only support a single DMA mask */
239 dev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
240 dev->dev.dma_mask = &dev->dev.coherent_dma_mask;
241
242 /* setup generic device info */
243 dev->dev.of_node = of_node_get(node);
244 dev->dev.fwnode = &node->fwnode;
245 dev->dev.parent = parent ? : &platform_bus;
246 dev->dev.platform_data = platform_data;
247 if (bus_id)
248 dev_set_name(&dev->dev, "%s", bus_id);
249 else
250 of_device_make_bus_id(&dev->dev);
251
252 /* Allow the HW Peripheral ID to be overridden */
253 prop = of_get_property(node, "arm,primecell-periphid", NULL);
254 if (prop)
255 dev->periphid = of_read_ulong(prop, 1);
256
257 /* Decode the IRQs and address ranges */
258 for (i = 0; i < AMBA_NR_IRQS; i++)
259 dev->irq[i] = irq_of_parse_and_map(node, i);
260
261 ret = of_address_to_resource(node, 0, &dev->res);
262 if (ret) {
263 pr_err("amba: of_address_to_resource() failed (%d) for %pOF\n",
264 ret, node);
265 goto err_free;
266 }
267
268 ret = amba_device_add(dev, &iomem_resource);
269 if (ret) {
270 pr_err("amba_device_add() failed (%d) for %pOF\n",
271 ret, node);
272 goto err_free;
273 }
274
275 return dev;
276
277err_free:
278 amba_device_put(dev);
279err_clear_flag:
280 of_node_clear_flag(node, OF_POPULATED);
281 return NULL;
282}
283#else /* CONFIG_ARM_AMBA */
284static struct amba_device *of_amba_device_create(struct device_node *node,
285 const char *bus_id,
286 void *platform_data,
287 struct device *parent)
288{
289 return NULL;
290}
291#endif /* CONFIG_ARM_AMBA */
292
293/**
294 * of_dev_lookup() - Given a device node, lookup the preferred Linux name
295 */
296static const struct of_dev_auxdata *of_dev_lookup(const struct of_dev_auxdata *lookup,
297 struct device_node *np)
298{
299 const struct of_dev_auxdata *auxdata;
300 struct resource res;
301 int compatible = 0;
302
303 if (!lookup)
304 return NULL;
305
306 auxdata = lookup;
307 for (; auxdata->compatible; auxdata++) {
308 if (!of_device_is_compatible(np, auxdata->compatible))
309 continue;
310 compatible++;
311 if (!of_address_to_resource(np, 0, &res))
312 if (res.start != auxdata->phys_addr)
313 continue;
314 pr_debug("%pOF: devname=%s\n", np, auxdata->name);
315 return auxdata;
316 }
317
318 if (!compatible)
319 return NULL;
320
321 /* Try compatible match if no phys_addr and name are specified */
322 auxdata = lookup;
323 for (; auxdata->compatible; auxdata++) {
324 if (!of_device_is_compatible(np, auxdata->compatible))
325 continue;
326 if (!auxdata->phys_addr && !auxdata->name) {
327 pr_debug("%pOF: compatible match\n", np);
328 return auxdata;
329 }
330 }
331
332 return NULL;
333}
334
335/**
336 * of_platform_bus_create() - Create a device for a node and its children.
337 * @bus: device node of the bus to instantiate
338 * @matches: match table for bus nodes
339 * @lookup: auxdata table for matching id and platform_data with device nodes
340 * @parent: parent for new device, or NULL for top level.
341 * @strict: require compatible property
342 *
343 * Creates a platform_device for the provided device_node, and optionally
344 * recursively create devices for all the child nodes.
345 */
346static int of_platform_bus_create(struct device_node *bus,
347 const struct of_device_id *matches,
348 const struct of_dev_auxdata *lookup,
349 struct device *parent, bool strict)
350{
351 const struct of_dev_auxdata *auxdata;
352 struct device_node *child;
353 struct platform_device *dev;
354 const char *bus_id = NULL;
355 void *platform_data = NULL;
356 int rc = 0;
357
358 /* Make sure it has a compatible property */
359 if (strict && (!of_get_property(bus, "compatible", NULL))) {
360 pr_debug("%s() - skipping %pOF, no compatible prop\n",
361 __func__, bus);
362 return 0;
363 }
364
365 /* Skip nodes for which we don't want to create devices */
366 if (unlikely(of_match_node(of_skipped_node_table, bus))) {
367 pr_debug("%s() - skipping %pOF node\n", __func__, bus);
368 return 0;
369 }
370
371 if (of_node_check_flag(bus, OF_POPULATED_BUS)) {
372 pr_debug("%s() - skipping %pOF, already populated\n",
373 __func__, bus);
374 return 0;
375 }
376
377 auxdata = of_dev_lookup(lookup, bus);
378 if (auxdata) {
379 bus_id = auxdata->name;
380 platform_data = auxdata->platform_data;
381 }
382
383 if (of_device_is_compatible(bus, "arm,primecell")) {
384 /*
385 * Don't return an error here to keep compatibility with older
386 * device tree files.
387 */
388 of_amba_device_create(bus, bus_id, platform_data, parent);
389 return 0;
390 }
391
392 dev = of_platform_device_create_pdata(bus, bus_id, platform_data, parent);
393 if (!dev || !of_match_node(matches, bus))
394 return 0;
395
396 for_each_child_of_node(bus, child) {
397 pr_debug(" create child: %pOF\n", child);
398 rc = of_platform_bus_create(child, matches, lookup, &dev->dev, strict);
399 if (rc) {
400 of_node_put(child);
401 break;
402 }
403 }
404 of_node_set_flag(bus, OF_POPULATED_BUS);
405 return rc;
406}
407
408/**
409 * of_platform_bus_probe() - Probe the device-tree for platform buses
410 * @root: parent of the first level to probe or NULL for the root of the tree
411 * @matches: match table for bus nodes
412 * @parent: parent to hook devices from, NULL for toplevel
413 *
414 * Note that children of the provided root are not instantiated as devices
415 * unless the specified root itself matches the bus list and is not NULL.
416 */
417int of_platform_bus_probe(struct device_node *root,
418 const struct of_device_id *matches,
419 struct device *parent)
420{
421 struct device_node *child;
422 int rc = 0;
423
424 root = root ? of_node_get(root) : of_find_node_by_path("/");
425 if (!root)
426 return -EINVAL;
427
428 pr_debug("%s()\n", __func__);
429 pr_debug(" starting at: %pOF\n", root);
430
431 /* Do a self check of bus type, if there's a match, create children */
432 if (of_match_node(matches, root)) {
433 rc = of_platform_bus_create(root, matches, NULL, parent, false);
434 } else for_each_child_of_node(root, child) {
435 if (!of_match_node(matches, child))
436 continue;
437 rc = of_platform_bus_create(child, matches, NULL, parent, false);
438 if (rc) {
439 of_node_put(child);
440 break;
441 }
442 }
443
444 of_node_put(root);
445 return rc;
446}
447EXPORT_SYMBOL(of_platform_bus_probe);
448
449/**
450 * of_platform_populate() - Populate platform_devices from device tree data
451 * @root: parent of the first level to probe or NULL for the root of the tree
452 * @matches: match table, NULL to use the default
453 * @lookup: auxdata table for matching id and platform_data with device nodes
454 * @parent: parent to hook devices from, NULL for toplevel
455 *
456 * Similar to of_platform_bus_probe(), this function walks the device tree
457 * and creates devices from nodes. It differs in that it follows the modern
458 * convention of requiring all device nodes to have a 'compatible' property,
459 * and it is suitable for creating devices which are children of the root
460 * node (of_platform_bus_probe will only create children of the root which
461 * are selected by the @matches argument).
462 *
463 * New board support should be using this function instead of
464 * of_platform_bus_probe().
465 *
466 * Returns 0 on success, < 0 on failure.
467 */
468int of_platform_populate(struct device_node *root,
469 const struct of_device_id *matches,
470 const struct of_dev_auxdata *lookup,
471 struct device *parent)
472{
473 struct device_node *child;
474 int rc = 0;
475
476 root = root ? of_node_get(root) : of_find_node_by_path("/");
477 if (!root)
478 return -EINVAL;
479
480 pr_debug("%s()\n", __func__);
481 pr_debug(" starting at: %pOF\n", root);
482
483 device_links_supplier_sync_state_pause();
484 for_each_child_of_node(root, child) {
485 rc = of_platform_bus_create(child, matches, lookup, parent, true);
486 if (rc) {
487 of_node_put(child);
488 break;
489 }
490 }
491 device_links_supplier_sync_state_resume();
492
493 of_node_set_flag(root, OF_POPULATED_BUS);
494
495 of_node_put(root);
496 return rc;
497}
498EXPORT_SYMBOL_GPL(of_platform_populate);
499
500int of_platform_default_populate(struct device_node *root,
501 const struct of_dev_auxdata *lookup,
502 struct device *parent)
503{
504 return of_platform_populate(root, of_default_bus_match_table, lookup,
505 parent);
506}
507EXPORT_SYMBOL_GPL(of_platform_default_populate);
508
509#ifndef CONFIG_PPC
510static const struct of_device_id reserved_mem_matches[] = {
511 { .compatible = "qcom,rmtfs-mem" },
512 { .compatible = "qcom,cmd-db" },
513 { .compatible = "ramoops" },
514 {}
515};
516
517static int __init of_platform_default_populate_init(void)
518{
519 struct device_node *node;
520
521 device_links_supplier_sync_state_pause();
522
523 if (!of_have_populated_dt())
524 return -ENODEV;
525
526 /*
527 * Handle certain compatibles explicitly, since we don't want to create
528 * platform_devices for every node in /reserved-memory with a
529 * "compatible",
530 */
531 for_each_matching_node(node, reserved_mem_matches)
532 of_platform_device_create(node, NULL, NULL);
533
534 node = of_find_node_by_path("/firmware");
535 if (node) {
536 of_platform_populate(node, NULL, NULL, NULL);
537 of_node_put(node);
538 }
539
540 /* Populate everything else. */
541 fw_devlink_pause();
542 of_platform_default_populate(NULL, NULL, NULL);
543 fw_devlink_resume();
544
545 return 0;
546}
547arch_initcall_sync(of_platform_default_populate_init);
548
549static int __init of_platform_sync_state_init(void)
550{
551 device_links_supplier_sync_state_resume();
552 return 0;
553}
554late_initcall_sync(of_platform_sync_state_init);
555#endif
556
557int of_platform_device_destroy(struct device *dev, void *data)
558{
559 /* Do not touch devices not populated from the device tree */
560 if (!dev->of_node || !of_node_check_flag(dev->of_node, OF_POPULATED))
561 return 0;
562
563 /* Recurse for any nodes that were treated as busses */
564 if (of_node_check_flag(dev->of_node, OF_POPULATED_BUS))
565 device_for_each_child(dev, NULL, of_platform_device_destroy);
566
567 of_node_clear_flag(dev->of_node, OF_POPULATED);
568 of_node_clear_flag(dev->of_node, OF_POPULATED_BUS);
569
570 if (dev->bus == &platform_bus_type)
571 platform_device_unregister(to_platform_device(dev));
572#ifdef CONFIG_ARM_AMBA
573 else if (dev->bus == &amba_bustype)
574 amba_device_unregister(to_amba_device(dev));
575#endif
576
577 return 0;
578}
579EXPORT_SYMBOL_GPL(of_platform_device_destroy);
580
581/**
582 * of_platform_depopulate() - Remove devices populated from device tree
583 * @parent: device which children will be removed
584 *
585 * Complementary to of_platform_populate(), this function removes children
586 * of the given device (and, recurrently, their children) that have been
587 * created from their respective device tree nodes (and only those,
588 * leaving others - eg. manually created - unharmed).
589 */
590void of_platform_depopulate(struct device *parent)
591{
592 if (parent->of_node && of_node_check_flag(parent->of_node, OF_POPULATED_BUS)) {
593 device_for_each_child(parent, NULL, of_platform_device_destroy);
594 of_node_clear_flag(parent->of_node, OF_POPULATED_BUS);
595 }
596}
597EXPORT_SYMBOL_GPL(of_platform_depopulate);
598
599static void devm_of_platform_populate_release(struct device *dev, void *res)
600{
601 of_platform_depopulate(*(struct device **)res);
602}
603
604/**
605 * devm_of_platform_populate() - Populate platform_devices from device tree data
606 * @dev: device that requested to populate from device tree data
607 *
608 * Similar to of_platform_populate(), but will automatically call
609 * of_platform_depopulate() when the device is unbound from the bus.
610 *
611 * Returns 0 on success, < 0 on failure.
612 */
613int devm_of_platform_populate(struct device *dev)
614{
615 struct device **ptr;
616 int ret;
617
618 if (!dev)
619 return -EINVAL;
620
621 ptr = devres_alloc(devm_of_platform_populate_release,
622 sizeof(*ptr), GFP_KERNEL);
623 if (!ptr)
624 return -ENOMEM;
625
626 ret = of_platform_populate(dev->of_node, NULL, NULL, dev);
627 if (ret) {
628 devres_free(ptr);
629 } else {
630 *ptr = dev;
631 devres_add(dev, ptr);
632 }
633
634 return ret;
635}
636EXPORT_SYMBOL_GPL(devm_of_platform_populate);
637
638static int devm_of_platform_match(struct device *dev, void *res, void *data)
639{
640 struct device **ptr = res;
641
642 if (!ptr) {
643 WARN_ON(!ptr);
644 return 0;
645 }
646
647 return *ptr == data;
648}
649
650/**
651 * devm_of_platform_depopulate() - Remove devices populated from device tree
652 * @dev: device that requested to depopulate from device tree data
653 *
654 * Complementary to devm_of_platform_populate(), this function removes children
655 * of the given device (and, recurrently, their children) that have been
656 * created from their respective device tree nodes (and only those,
657 * leaving others - eg. manually created - unharmed).
658 */
659void devm_of_platform_depopulate(struct device *dev)
660{
661 int ret;
662
663 ret = devres_release(dev, devm_of_platform_populate_release,
664 devm_of_platform_match, dev);
665
666 WARN_ON(ret);
667}
668EXPORT_SYMBOL_GPL(devm_of_platform_depopulate);
669
670#ifdef CONFIG_OF_DYNAMIC
671static int of_platform_notify(struct notifier_block *nb,
672 unsigned long action, void *arg)
673{
674 struct of_reconfig_data *rd = arg;
675 struct platform_device *pdev_parent, *pdev;
676 bool children_left;
677
678 switch (of_reconfig_get_state_change(action, rd)) {
679 case OF_RECONFIG_CHANGE_ADD:
680 /* verify that the parent is a bus */
681 if (!of_node_check_flag(rd->dn->parent, OF_POPULATED_BUS))
682 return NOTIFY_OK; /* not for us */
683
684 /* already populated? (driver using of_populate manually) */
685 if (of_node_check_flag(rd->dn, OF_POPULATED))
686 return NOTIFY_OK;
687
688 /* pdev_parent may be NULL when no bus platform device */
689 pdev_parent = of_find_device_by_node(rd->dn->parent);
690 pdev = of_platform_device_create(rd->dn, NULL,
691 pdev_parent ? &pdev_parent->dev : NULL);
692 of_dev_put(pdev_parent);
693
694 if (pdev == NULL) {
695 pr_err("%s: failed to create for '%pOF'\n",
696 __func__, rd->dn);
697 /* of_platform_device_create tosses the error code */
698 return notifier_from_errno(-EINVAL);
699 }
700 break;
701
702 case OF_RECONFIG_CHANGE_REMOVE:
703
704 /* already depopulated? */
705 if (!of_node_check_flag(rd->dn, OF_POPULATED))
706 return NOTIFY_OK;
707
708 /* find our device by node */
709 pdev = of_find_device_by_node(rd->dn);
710 if (pdev == NULL)
711 return NOTIFY_OK; /* no? not meant for us */
712
713 /* unregister takes one ref away */
714 of_platform_device_destroy(&pdev->dev, &children_left);
715
716 /* and put the reference of the find */
717 of_dev_put(pdev);
718 break;
719 }
720
721 return NOTIFY_OK;
722}
723
724static struct notifier_block platform_of_notifier = {
725 .notifier_call = of_platform_notify,
726};
727
728void of_platform_register_reconfig_notifier(void)
729{
730 WARN_ON(of_reconfig_notifier_register(&platform_of_notifier));
731}
732#endif /* CONFIG_OF_DYNAMIC */
733
734#endif /* CONFIG_OF_ADDRESS */
1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * Copyright (C) 2006 Benjamin Herrenschmidt, IBM Corp.
4 * <benh@kernel.crashing.org>
5 * and Arnd Bergmann, IBM Corp.
6 * Merged from powerpc/kernel/of_platform.c and
7 * sparc{,64}/kernel/of_device.c by Stephen Rothwell
8 */
9
10#define pr_fmt(fmt) "OF: " fmt
11
12#include <linux/errno.h>
13#include <linux/module.h>
14#include <linux/amba/bus.h>
15#include <linux/device.h>
16#include <linux/dma-mapping.h>
17#include <linux/slab.h>
18#include <linux/of_address.h>
19#include <linux/of_device.h>
20#include <linux/of_irq.h>
21#include <linux/of_platform.h>
22#include <linux/platform_device.h>
23#include <linux/sysfb.h>
24
25#include "of_private.h"
26
27const struct of_device_id of_default_bus_match_table[] = {
28 { .compatible = "simple-bus", },
29 { .compatible = "simple-mfd", },
30 { .compatible = "isa", },
31#ifdef CONFIG_ARM_AMBA
32 { .compatible = "arm,amba-bus", },
33#endif /* CONFIG_ARM_AMBA */
34 {} /* Empty terminated list */
35};
36
37/**
38 * of_find_device_by_node - Find the platform_device associated with a node
39 * @np: Pointer to device tree node
40 *
41 * Takes a reference to the embedded struct device which needs to be dropped
42 * after use.
43 *
44 * Return: platform_device pointer, or NULL if not found
45 */
46struct platform_device *of_find_device_by_node(struct device_node *np)
47{
48 struct device *dev;
49
50 dev = bus_find_device_by_of_node(&platform_bus_type, np);
51 return dev ? to_platform_device(dev) : NULL;
52}
53EXPORT_SYMBOL(of_find_device_by_node);
54
55int of_device_add(struct platform_device *ofdev)
56{
57 BUG_ON(ofdev->dev.of_node == NULL);
58
59 /* name and id have to be set so that the platform bus doesn't get
60 * confused on matching */
61 ofdev->name = dev_name(&ofdev->dev);
62 ofdev->id = PLATFORM_DEVID_NONE;
63
64 /*
65 * If this device has not binding numa node in devicetree, that is
66 * of_node_to_nid returns NUMA_NO_NODE. device_add will assume that this
67 * device is on the same node as the parent.
68 */
69 set_dev_node(&ofdev->dev, of_node_to_nid(ofdev->dev.of_node));
70
71 return device_add(&ofdev->dev);
72}
73
74int of_device_register(struct platform_device *pdev)
75{
76 device_initialize(&pdev->dev);
77 return of_device_add(pdev);
78}
79EXPORT_SYMBOL(of_device_register);
80
81void of_device_unregister(struct platform_device *ofdev)
82{
83 device_unregister(&ofdev->dev);
84}
85EXPORT_SYMBOL(of_device_unregister);
86
87#ifdef CONFIG_OF_ADDRESS
88static const struct of_device_id of_skipped_node_table[] = {
89 { .compatible = "operating-points-v2", },
90 {} /* Empty terminated list */
91};
92
93/*
94 * The following routines scan a subtree and registers a device for
95 * each applicable node.
96 *
97 * Note: sparc doesn't use these routines because it has a different
98 * mechanism for creating devices from device tree nodes.
99 */
100
101/**
102 * of_device_alloc - Allocate and initialize an of_device
103 * @np: device node to assign to device
104 * @bus_id: Name to assign to the device. May be null to use default name.
105 * @parent: Parent device.
106 */
107struct platform_device *of_device_alloc(struct device_node *np,
108 const char *bus_id,
109 struct device *parent)
110{
111 struct platform_device *dev;
112 int rc, i, num_reg = 0;
113 struct resource *res;
114
115 dev = platform_device_alloc("", PLATFORM_DEVID_NONE);
116 if (!dev)
117 return NULL;
118
119 /* count the io resources */
120 num_reg = of_address_count(np);
121
122 /* Populate the resource table */
123 if (num_reg) {
124 res = kcalloc(num_reg, sizeof(*res), GFP_KERNEL);
125 if (!res) {
126 platform_device_put(dev);
127 return NULL;
128 }
129
130 dev->num_resources = num_reg;
131 dev->resource = res;
132 for (i = 0; i < num_reg; i++, res++) {
133 rc = of_address_to_resource(np, i, res);
134 WARN_ON(rc);
135 }
136 }
137
138 /* setup generic device info */
139 device_set_node(&dev->dev, of_fwnode_handle(of_node_get(np)));
140 dev->dev.parent = parent ? : &platform_bus;
141
142 if (bus_id)
143 dev_set_name(&dev->dev, "%s", bus_id);
144 else
145 of_device_make_bus_id(&dev->dev);
146
147 return dev;
148}
149EXPORT_SYMBOL(of_device_alloc);
150
151/**
152 * of_platform_device_create_pdata - Alloc, initialize and register an of_device
153 * @np: pointer to node to create device for
154 * @bus_id: name to assign device
155 * @platform_data: pointer to populate platform_data pointer with
156 * @parent: Linux device model parent device.
157 *
158 * Return: Pointer to created platform device, or NULL if a device was not
159 * registered. Unavailable devices will not get registered.
160 */
161static struct platform_device *of_platform_device_create_pdata(
162 struct device_node *np,
163 const char *bus_id,
164 void *platform_data,
165 struct device *parent)
166{
167 struct platform_device *dev;
168
169 pr_debug("create platform device: %pOF\n", np);
170
171 if (!of_device_is_available(np) ||
172 of_node_test_and_set_flag(np, OF_POPULATED))
173 return NULL;
174
175 dev = of_device_alloc(np, bus_id, parent);
176 if (!dev)
177 goto err_clear_flag;
178
179 dev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
180 if (!dev->dev.dma_mask)
181 dev->dev.dma_mask = &dev->dev.coherent_dma_mask;
182 dev->dev.bus = &platform_bus_type;
183 dev->dev.platform_data = platform_data;
184 of_msi_configure(&dev->dev, dev->dev.of_node);
185
186 if (of_device_add(dev) != 0) {
187 platform_device_put(dev);
188 goto err_clear_flag;
189 }
190
191 return dev;
192
193err_clear_flag:
194 of_node_clear_flag(np, OF_POPULATED);
195 return NULL;
196}
197
198/**
199 * of_platform_device_create - Alloc, initialize and register an of_device
200 * @np: pointer to node to create device for
201 * @bus_id: name to assign device
202 * @parent: Linux device model parent device.
203 *
204 * Return: Pointer to created platform device, or NULL if a device was not
205 * registered. Unavailable devices will not get registered.
206 */
207struct platform_device *of_platform_device_create(struct device_node *np,
208 const char *bus_id,
209 struct device *parent)
210{
211 return of_platform_device_create_pdata(np, bus_id, NULL, parent);
212}
213EXPORT_SYMBOL(of_platform_device_create);
214
215#ifdef CONFIG_ARM_AMBA
216static struct amba_device *of_amba_device_create(struct device_node *node,
217 const char *bus_id,
218 void *platform_data,
219 struct device *parent)
220{
221 struct amba_device *dev;
222 int ret;
223
224 pr_debug("Creating amba device %pOF\n", node);
225
226 if (!of_device_is_available(node) ||
227 of_node_test_and_set_flag(node, OF_POPULATED))
228 return NULL;
229
230 dev = amba_device_alloc(NULL, 0, 0);
231 if (!dev)
232 goto err_clear_flag;
233
234 /* AMBA devices only support a single DMA mask */
235 dev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
236 dev->dev.dma_mask = &dev->dev.coherent_dma_mask;
237
238 /* setup generic device info */
239 device_set_node(&dev->dev, of_fwnode_handle(node));
240 dev->dev.parent = parent ? : &platform_bus;
241 dev->dev.platform_data = platform_data;
242 if (bus_id)
243 dev_set_name(&dev->dev, "%s", bus_id);
244 else
245 of_device_make_bus_id(&dev->dev);
246
247 /* Allow the HW Peripheral ID to be overridden */
248 of_property_read_u32(node, "arm,primecell-periphid", &dev->periphid);
249
250 ret = of_address_to_resource(node, 0, &dev->res);
251 if (ret) {
252 pr_err("amba: of_address_to_resource() failed (%d) for %pOF\n",
253 ret, node);
254 goto err_free;
255 }
256
257 ret = amba_device_add(dev, &iomem_resource);
258 if (ret) {
259 pr_err("amba_device_add() failed (%d) for %pOF\n",
260 ret, node);
261 goto err_free;
262 }
263
264 return dev;
265
266err_free:
267 amba_device_put(dev);
268err_clear_flag:
269 of_node_clear_flag(node, OF_POPULATED);
270 return NULL;
271}
272#else /* CONFIG_ARM_AMBA */
273static struct amba_device *of_amba_device_create(struct device_node *node,
274 const char *bus_id,
275 void *platform_data,
276 struct device *parent)
277{
278 return NULL;
279}
280#endif /* CONFIG_ARM_AMBA */
281
282/*
283 * of_dev_lookup() - Given a device node, lookup the preferred Linux name
284 */
285static const struct of_dev_auxdata *of_dev_lookup(const struct of_dev_auxdata *lookup,
286 struct device_node *np)
287{
288 const struct of_dev_auxdata *auxdata;
289 struct resource res;
290 int compatible = 0;
291
292 if (!lookup)
293 return NULL;
294
295 auxdata = lookup;
296 for (; auxdata->compatible; auxdata++) {
297 if (!of_device_is_compatible(np, auxdata->compatible))
298 continue;
299 compatible++;
300 if (!of_address_to_resource(np, 0, &res))
301 if (res.start != auxdata->phys_addr)
302 continue;
303 pr_debug("%pOF: devname=%s\n", np, auxdata->name);
304 return auxdata;
305 }
306
307 if (!compatible)
308 return NULL;
309
310 /* Try compatible match if no phys_addr and name are specified */
311 auxdata = lookup;
312 for (; auxdata->compatible; auxdata++) {
313 if (!of_device_is_compatible(np, auxdata->compatible))
314 continue;
315 if (!auxdata->phys_addr && !auxdata->name) {
316 pr_debug("%pOF: compatible match\n", np);
317 return auxdata;
318 }
319 }
320
321 return NULL;
322}
323
324/**
325 * of_platform_bus_create() - Create a device for a node and its children.
326 * @bus: device node of the bus to instantiate
327 * @matches: match table for bus nodes
328 * @lookup: auxdata table for matching id and platform_data with device nodes
329 * @parent: parent for new device, or NULL for top level.
330 * @strict: require compatible property
331 *
332 * Creates a platform_device for the provided device_node, and optionally
333 * recursively create devices for all the child nodes.
334 */
335static int of_platform_bus_create(struct device_node *bus,
336 const struct of_device_id *matches,
337 const struct of_dev_auxdata *lookup,
338 struct device *parent, bool strict)
339{
340 const struct of_dev_auxdata *auxdata;
341 struct device_node *child;
342 struct platform_device *dev;
343 const char *bus_id = NULL;
344 void *platform_data = NULL;
345 int rc = 0;
346
347 /* Make sure it has a compatible property */
348 if (strict && (!of_get_property(bus, "compatible", NULL))) {
349 pr_debug("%s() - skipping %pOF, no compatible prop\n",
350 __func__, bus);
351 return 0;
352 }
353
354 /* Skip nodes for which we don't want to create devices */
355 if (unlikely(of_match_node(of_skipped_node_table, bus))) {
356 pr_debug("%s() - skipping %pOF node\n", __func__, bus);
357 return 0;
358 }
359
360 if (of_node_check_flag(bus, OF_POPULATED_BUS)) {
361 pr_debug("%s() - skipping %pOF, already populated\n",
362 __func__, bus);
363 return 0;
364 }
365
366 auxdata = of_dev_lookup(lookup, bus);
367 if (auxdata) {
368 bus_id = auxdata->name;
369 platform_data = auxdata->platform_data;
370 }
371
372 if (of_device_is_compatible(bus, "arm,primecell")) {
373 /*
374 * Don't return an error here to keep compatibility with older
375 * device tree files.
376 */
377 of_amba_device_create(bus, bus_id, platform_data, parent);
378 return 0;
379 }
380
381 dev = of_platform_device_create_pdata(bus, bus_id, platform_data, parent);
382 if (!dev || !of_match_node(matches, bus))
383 return 0;
384
385 for_each_child_of_node(bus, child) {
386 pr_debug(" create child: %pOF\n", child);
387 rc = of_platform_bus_create(child, matches, lookup, &dev->dev, strict);
388 if (rc) {
389 of_node_put(child);
390 break;
391 }
392 }
393 of_node_set_flag(bus, OF_POPULATED_BUS);
394 return rc;
395}
396
397/**
398 * of_platform_bus_probe() - Probe the device-tree for platform buses
399 * @root: parent of the first level to probe or NULL for the root of the tree
400 * @matches: match table for bus nodes
401 * @parent: parent to hook devices from, NULL for toplevel
402 *
403 * Note that children of the provided root are not instantiated as devices
404 * unless the specified root itself matches the bus list and is not NULL.
405 */
406int of_platform_bus_probe(struct device_node *root,
407 const struct of_device_id *matches,
408 struct device *parent)
409{
410 struct device_node *child;
411 int rc = 0;
412
413 root = root ? of_node_get(root) : of_find_node_by_path("/");
414 if (!root)
415 return -EINVAL;
416
417 pr_debug("%s()\n", __func__);
418 pr_debug(" starting at: %pOF\n", root);
419
420 /* Do a self check of bus type, if there's a match, create children */
421 if (of_match_node(matches, root)) {
422 rc = of_platform_bus_create(root, matches, NULL, parent, false);
423 } else for_each_child_of_node(root, child) {
424 if (!of_match_node(matches, child))
425 continue;
426 rc = of_platform_bus_create(child, matches, NULL, parent, false);
427 if (rc) {
428 of_node_put(child);
429 break;
430 }
431 }
432
433 of_node_put(root);
434 return rc;
435}
436EXPORT_SYMBOL(of_platform_bus_probe);
437
438/**
439 * of_platform_populate() - Populate platform_devices from device tree data
440 * @root: parent of the first level to probe or NULL for the root of the tree
441 * @matches: match table, NULL to use the default
442 * @lookup: auxdata table for matching id and platform_data with device nodes
443 * @parent: parent to hook devices from, NULL for toplevel
444 *
445 * Similar to of_platform_bus_probe(), this function walks the device tree
446 * and creates devices from nodes. It differs in that it follows the modern
447 * convention of requiring all device nodes to have a 'compatible' property,
448 * and it is suitable for creating devices which are children of the root
449 * node (of_platform_bus_probe will only create children of the root which
450 * are selected by the @matches argument).
451 *
452 * New board support should be using this function instead of
453 * of_platform_bus_probe().
454 *
455 * Return: 0 on success, < 0 on failure.
456 */
457int of_platform_populate(struct device_node *root,
458 const struct of_device_id *matches,
459 const struct of_dev_auxdata *lookup,
460 struct device *parent)
461{
462 struct device_node *child;
463 int rc = 0;
464
465 root = root ? of_node_get(root) : of_find_node_by_path("/");
466 if (!root)
467 return -EINVAL;
468
469 pr_debug("%s()\n", __func__);
470 pr_debug(" starting at: %pOF\n", root);
471
472 device_links_supplier_sync_state_pause();
473 for_each_child_of_node(root, child) {
474 rc = of_platform_bus_create(child, matches, lookup, parent, true);
475 if (rc) {
476 of_node_put(child);
477 break;
478 }
479 }
480 device_links_supplier_sync_state_resume();
481
482 of_node_set_flag(root, OF_POPULATED_BUS);
483
484 of_node_put(root);
485 return rc;
486}
487EXPORT_SYMBOL_GPL(of_platform_populate);
488
489int of_platform_default_populate(struct device_node *root,
490 const struct of_dev_auxdata *lookup,
491 struct device *parent)
492{
493 return of_platform_populate(root, of_default_bus_match_table, lookup,
494 parent);
495}
496EXPORT_SYMBOL_GPL(of_platform_default_populate);
497
498static const struct of_device_id reserved_mem_matches[] = {
499 { .compatible = "phram" },
500 { .compatible = "qcom,rmtfs-mem" },
501 { .compatible = "qcom,cmd-db" },
502 { .compatible = "qcom,smem" },
503 { .compatible = "ramoops" },
504 { .compatible = "nvmem-rmem" },
505 { .compatible = "google,open-dice" },
506 {}
507};
508
509static int __init of_platform_default_populate_init(void)
510{
511 struct device_node *node;
512
513 device_links_supplier_sync_state_pause();
514
515 if (IS_ENABLED(CONFIG_PPC)) {
516 struct device_node *boot_display = NULL;
517 struct platform_device *dev;
518 int display_number = 0;
519 int ret;
520
521 /* Check if we have a MacOS display without a node spec */
522 if (of_property_present(of_chosen, "linux,bootx-noscreen")) {
523 /*
524 * The old code tried to work out which node was the MacOS
525 * display based on the address. I'm dropping that since the
526 * lack of a node spec only happens with old BootX versions
527 * (users can update) and with this code, they'll still get
528 * a display (just not the palette hacks).
529 */
530 dev = platform_device_alloc("bootx-noscreen", 0);
531 if (WARN_ON(!dev))
532 return -ENOMEM;
533 ret = platform_device_add(dev);
534 if (WARN_ON(ret)) {
535 platform_device_put(dev);
536 return ret;
537 }
538 }
539
540 /*
541 * For OF framebuffers, first create the device for the boot display,
542 * then for the other framebuffers. Only fail for the boot display;
543 * ignore errors for the rest.
544 */
545 for_each_node_by_type(node, "display") {
546 if (!of_get_property(node, "linux,opened", NULL) ||
547 !of_get_property(node, "linux,boot-display", NULL))
548 continue;
549 dev = of_platform_device_create(node, "of-display", NULL);
550 of_node_put(node);
551 if (WARN_ON(!dev))
552 return -ENOMEM;
553 boot_display = node;
554 display_number++;
555 break;
556 }
557 for_each_node_by_type(node, "display") {
558 char buf[14];
559 const char *of_display_format = "of-display.%d";
560
561 if (!of_get_property(node, "linux,opened", NULL) || node == boot_display)
562 continue;
563 ret = snprintf(buf, sizeof(buf), of_display_format, display_number++);
564 if (ret < sizeof(buf))
565 of_platform_device_create(node, buf, NULL);
566 }
567
568 } else {
569 /*
570 * Handle certain compatibles explicitly, since we don't want to create
571 * platform_devices for every node in /reserved-memory with a
572 * "compatible",
573 */
574 for_each_matching_node(node, reserved_mem_matches)
575 of_platform_device_create(node, NULL, NULL);
576
577 node = of_find_node_by_path("/firmware");
578 if (node) {
579 of_platform_populate(node, NULL, NULL, NULL);
580 of_node_put(node);
581 }
582
583 node = of_get_compatible_child(of_chosen, "simple-framebuffer");
584 if (node) {
585 /*
586 * Since a "simple-framebuffer" device is already added
587 * here, disable the Generic System Framebuffers (sysfb)
588 * to prevent it from registering another device for the
589 * system framebuffer later (e.g: using the screen_info
590 * data that may had been filled as well).
591 *
592 * This can happen for example on DT systems that do EFI
593 * booting and may provide a GOP handle to the EFI stub.
594 */
595 sysfb_disable();
596 of_platform_device_create(node, NULL, NULL);
597 of_node_put(node);
598 }
599
600 /* Populate everything else. */
601 of_platform_default_populate(NULL, NULL, NULL);
602 }
603
604 return 0;
605}
606arch_initcall_sync(of_platform_default_populate_init);
607
608static int __init of_platform_sync_state_init(void)
609{
610 device_links_supplier_sync_state_resume();
611 return 0;
612}
613late_initcall_sync(of_platform_sync_state_init);
614
615int of_platform_device_destroy(struct device *dev, void *data)
616{
617 /* Do not touch devices not populated from the device tree */
618 if (!dev->of_node || !of_node_check_flag(dev->of_node, OF_POPULATED))
619 return 0;
620
621 /* Recurse for any nodes that were treated as busses */
622 if (of_node_check_flag(dev->of_node, OF_POPULATED_BUS))
623 device_for_each_child(dev, NULL, of_platform_device_destroy);
624
625 of_node_clear_flag(dev->of_node, OF_POPULATED);
626 of_node_clear_flag(dev->of_node, OF_POPULATED_BUS);
627
628 if (dev->bus == &platform_bus_type)
629 platform_device_unregister(to_platform_device(dev));
630#ifdef CONFIG_ARM_AMBA
631 else if (dev->bus == &amba_bustype)
632 amba_device_unregister(to_amba_device(dev));
633#endif
634
635 return 0;
636}
637EXPORT_SYMBOL_GPL(of_platform_device_destroy);
638
639/**
640 * of_platform_depopulate() - Remove devices populated from device tree
641 * @parent: device which children will be removed
642 *
643 * Complementary to of_platform_populate(), this function removes children
644 * of the given device (and, recursively, their children) that have been
645 * created from their respective device tree nodes (and only those,
646 * leaving others - eg. manually created - unharmed).
647 */
648void of_platform_depopulate(struct device *parent)
649{
650 if (parent->of_node && of_node_check_flag(parent->of_node, OF_POPULATED_BUS)) {
651 device_for_each_child_reverse(parent, NULL, of_platform_device_destroy);
652 of_node_clear_flag(parent->of_node, OF_POPULATED_BUS);
653 }
654}
655EXPORT_SYMBOL_GPL(of_platform_depopulate);
656
657static void devm_of_platform_populate_release(struct device *dev, void *res)
658{
659 of_platform_depopulate(*(struct device **)res);
660}
661
662/**
663 * devm_of_platform_populate() - Populate platform_devices from device tree data
664 * @dev: device that requested to populate from device tree data
665 *
666 * Similar to of_platform_populate(), but will automatically call
667 * of_platform_depopulate() when the device is unbound from the bus.
668 *
669 * Return: 0 on success, < 0 on failure.
670 */
671int devm_of_platform_populate(struct device *dev)
672{
673 struct device **ptr;
674 int ret;
675
676 if (!dev)
677 return -EINVAL;
678
679 ptr = devres_alloc(devm_of_platform_populate_release,
680 sizeof(*ptr), GFP_KERNEL);
681 if (!ptr)
682 return -ENOMEM;
683
684 ret = of_platform_populate(dev->of_node, NULL, NULL, dev);
685 if (ret) {
686 devres_free(ptr);
687 } else {
688 *ptr = dev;
689 devres_add(dev, ptr);
690 }
691
692 return ret;
693}
694EXPORT_SYMBOL_GPL(devm_of_platform_populate);
695
696static int devm_of_platform_match(struct device *dev, void *res, void *data)
697{
698 struct device **ptr = res;
699
700 if (!ptr) {
701 WARN_ON(!ptr);
702 return 0;
703 }
704
705 return *ptr == data;
706}
707
708/**
709 * devm_of_platform_depopulate() - Remove devices populated from device tree
710 * @dev: device that requested to depopulate from device tree data
711 *
712 * Complementary to devm_of_platform_populate(), this function removes children
713 * of the given device (and, recursively, their children) that have been
714 * created from their respective device tree nodes (and only those,
715 * leaving others - eg. manually created - unharmed).
716 */
717void devm_of_platform_depopulate(struct device *dev)
718{
719 int ret;
720
721 ret = devres_release(dev, devm_of_platform_populate_release,
722 devm_of_platform_match, dev);
723
724 WARN_ON(ret);
725}
726EXPORT_SYMBOL_GPL(devm_of_platform_depopulate);
727
728#ifdef CONFIG_OF_DYNAMIC
729static int of_platform_notify(struct notifier_block *nb,
730 unsigned long action, void *arg)
731{
732 struct of_reconfig_data *rd = arg;
733 struct platform_device *pdev_parent, *pdev;
734 bool children_left;
735
736 switch (of_reconfig_get_state_change(action, rd)) {
737 case OF_RECONFIG_CHANGE_ADD:
738 /* verify that the parent is a bus */
739 if (!of_node_check_flag(rd->dn->parent, OF_POPULATED_BUS))
740 return NOTIFY_OK; /* not for us */
741
742 /* already populated? (driver using of_populate manually) */
743 if (of_node_check_flag(rd->dn, OF_POPULATED))
744 return NOTIFY_OK;
745
746 /*
747 * Clear the flag before adding the device so that fw_devlink
748 * doesn't skip adding consumers to this device.
749 */
750 rd->dn->fwnode.flags &= ~FWNODE_FLAG_NOT_DEVICE;
751 /* pdev_parent may be NULL when no bus platform device */
752 pdev_parent = of_find_device_by_node(rd->dn->parent);
753 pdev = of_platform_device_create(rd->dn, NULL,
754 pdev_parent ? &pdev_parent->dev : NULL);
755 platform_device_put(pdev_parent);
756
757 if (pdev == NULL) {
758 pr_err("%s: failed to create for '%pOF'\n",
759 __func__, rd->dn);
760 /* of_platform_device_create tosses the error code */
761 return notifier_from_errno(-EINVAL);
762 }
763 break;
764
765 case OF_RECONFIG_CHANGE_REMOVE:
766
767 /* already depopulated? */
768 if (!of_node_check_flag(rd->dn, OF_POPULATED))
769 return NOTIFY_OK;
770
771 /* find our device by node */
772 pdev = of_find_device_by_node(rd->dn);
773 if (pdev == NULL)
774 return NOTIFY_OK; /* no? not meant for us */
775
776 /* unregister takes one ref away */
777 of_platform_device_destroy(&pdev->dev, &children_left);
778
779 /* and put the reference of the find */
780 platform_device_put(pdev);
781 break;
782 }
783
784 return NOTIFY_OK;
785}
786
787static struct notifier_block platform_of_notifier = {
788 .notifier_call = of_platform_notify,
789};
790
791void of_platform_register_reconfig_notifier(void)
792{
793 WARN_ON(of_reconfig_notifier_register(&platform_of_notifier));
794}
795#endif /* CONFIG_OF_DYNAMIC */
796
797#endif /* CONFIG_OF_ADDRESS */