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
27 const 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 */
of_find_device_by_node(struct device_node * np)46 struct 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 }
53 EXPORT_SYMBOL(of_find_device_by_node);
54
of_device_add(struct platform_device * ofdev)55 int 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
of_device_register(struct platform_device * pdev)74 int of_device_register(struct platform_device *pdev)
75 {
76 device_initialize(&pdev->dev);
77 return of_device_add(pdev);
78 }
79 EXPORT_SYMBOL(of_device_register);
80
of_device_unregister(struct platform_device * ofdev)81 void of_device_unregister(struct platform_device *ofdev)
82 {
83 device_unregister(&ofdev->dev);
84 }
85 EXPORT_SYMBOL(of_device_unregister);
86
87 #ifdef CONFIG_OF_ADDRESS
88 static 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 */
of_device_alloc(struct device_node * np,const char * bus_id,struct device * parent)107 struct 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 }
149 EXPORT_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 */
of_platform_device_create_pdata(struct device_node * np,const char * bus_id,void * platform_data,struct device * parent)161 static 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 if (!of_device_is_available(np) ||
170 of_node_test_and_set_flag(np, OF_POPULATED))
171 return NULL;
172
173 dev = of_device_alloc(np, bus_id, parent);
174 if (!dev)
175 goto err_clear_flag;
176
177 dev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
178 if (!dev->dev.dma_mask)
179 dev->dev.dma_mask = &dev->dev.coherent_dma_mask;
180 dev->dev.bus = &platform_bus_type;
181 dev->dev.platform_data = platform_data;
182 of_msi_configure(&dev->dev, dev->dev.of_node);
183
184 if (of_device_add(dev) != 0) {
185 platform_device_put(dev);
186 goto err_clear_flag;
187 }
188
189 return dev;
190
191 err_clear_flag:
192 of_node_clear_flag(np, OF_POPULATED);
193 return NULL;
194 }
195
196 /**
197 * of_platform_device_create - Alloc, initialize and register an of_device
198 * @np: pointer to node to create device for
199 * @bus_id: name to assign device
200 * @parent: Linux device model parent device.
201 *
202 * Return: Pointer to created platform device, or NULL if a device was not
203 * registered. Unavailable devices will not get registered.
204 */
of_platform_device_create(struct device_node * np,const char * bus_id,struct device * parent)205 struct platform_device *of_platform_device_create(struct device_node *np,
206 const char *bus_id,
207 struct device *parent)
208 {
209 return of_platform_device_create_pdata(np, bus_id, NULL, parent);
210 }
211 EXPORT_SYMBOL(of_platform_device_create);
212
213 #ifdef CONFIG_ARM_AMBA
of_amba_device_create(struct device_node * node,const char * bus_id,void * platform_data,struct device * parent)214 static struct amba_device *of_amba_device_create(struct device_node *node,
215 const char *bus_id,
216 void *platform_data,
217 struct device *parent)
218 {
219 struct amba_device *dev;
220 int ret;
221
222 pr_debug("Creating amba device %pOF\n", node);
223
224 if (!of_device_is_available(node) ||
225 of_node_test_and_set_flag(node, OF_POPULATED))
226 return NULL;
227
228 dev = amba_device_alloc(NULL, 0, 0);
229 if (!dev)
230 goto err_clear_flag;
231
232 /* AMBA devices only support a single DMA mask */
233 dev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
234 dev->dev.dma_mask = &dev->dev.coherent_dma_mask;
235
236 /* setup generic device info */
237 device_set_node(&dev->dev, of_fwnode_handle(node));
238 dev->dev.parent = parent ? : &platform_bus;
239 dev->dev.platform_data = platform_data;
240 if (bus_id)
241 dev_set_name(&dev->dev, "%s", bus_id);
242 else
243 of_device_make_bus_id(&dev->dev);
244
245 /* Allow the HW Peripheral ID to be overridden */
246 of_property_read_u32(node, "arm,primecell-periphid", &dev->periphid);
247
248 ret = of_address_to_resource(node, 0, &dev->res);
249 if (ret) {
250 pr_err("amba: of_address_to_resource() failed (%d) for %pOF\n",
251 ret, node);
252 goto err_free;
253 }
254
255 ret = amba_device_add(dev, &iomem_resource);
256 if (ret) {
257 pr_err("amba_device_add() failed (%d) for %pOF\n",
258 ret, node);
259 goto err_free;
260 }
261
262 return dev;
263
264 err_free:
265 amba_device_put(dev);
266 err_clear_flag:
267 of_node_clear_flag(node, OF_POPULATED);
268 return NULL;
269 }
270 #else /* CONFIG_ARM_AMBA */
of_amba_device_create(struct device_node * node,const char * bus_id,void * platform_data,struct device * parent)271 static struct amba_device *of_amba_device_create(struct device_node *node,
272 const char *bus_id,
273 void *platform_data,
274 struct device *parent)
275 {
276 return NULL;
277 }
278 #endif /* CONFIG_ARM_AMBA */
279
280 /*
281 * of_dev_lookup() - Given a device node, lookup the preferred Linux name
282 */
of_dev_lookup(const struct of_dev_auxdata * lookup,struct device_node * np)283 static const struct of_dev_auxdata *of_dev_lookup(const struct of_dev_auxdata *lookup,
284 struct device_node *np)
285 {
286 const struct of_dev_auxdata *auxdata;
287 struct resource res;
288 int compatible = 0;
289
290 if (!lookup)
291 return NULL;
292
293 auxdata = lookup;
294 for (; auxdata->compatible; auxdata++) {
295 if (!of_device_is_compatible(np, auxdata->compatible))
296 continue;
297 compatible++;
298 if (!of_address_to_resource(np, 0, &res))
299 if (res.start != auxdata->phys_addr)
300 continue;
301 pr_debug("%pOF: devname=%s\n", np, auxdata->name);
302 return auxdata;
303 }
304
305 if (!compatible)
306 return NULL;
307
308 /* Try compatible match if no phys_addr and name are specified */
309 auxdata = lookup;
310 for (; auxdata->compatible; auxdata++) {
311 if (!of_device_is_compatible(np, auxdata->compatible))
312 continue;
313 if (!auxdata->phys_addr && !auxdata->name) {
314 pr_debug("%pOF: compatible match\n", np);
315 return auxdata;
316 }
317 }
318
319 return NULL;
320 }
321
322 /**
323 * of_platform_bus_create() - Create a device for a node and its children.
324 * @bus: device node of the bus to instantiate
325 * @matches: match table for bus nodes
326 * @lookup: auxdata table for matching id and platform_data with device nodes
327 * @parent: parent for new device, or NULL for top level.
328 * @strict: require compatible property
329 *
330 * Creates a platform_device for the provided device_node, and optionally
331 * recursively create devices for all the child nodes.
332 */
of_platform_bus_create(struct device_node * bus,const struct of_device_id * matches,const struct of_dev_auxdata * lookup,struct device * parent,bool strict)333 static int of_platform_bus_create(struct device_node *bus,
334 const struct of_device_id *matches,
335 const struct of_dev_auxdata *lookup,
336 struct device *parent, bool strict)
337 {
338 const struct of_dev_auxdata *auxdata;
339 struct device_node *child;
340 struct platform_device *dev;
341 const char *bus_id = NULL;
342 void *platform_data = NULL;
343 int rc = 0;
344
345 /* Make sure it has a compatible property */
346 if (strict && (!of_get_property(bus, "compatible", NULL))) {
347 pr_debug("%s() - skipping %pOF, no compatible prop\n",
348 __func__, bus);
349 return 0;
350 }
351
352 /* Skip nodes for which we don't want to create devices */
353 if (unlikely(of_match_node(of_skipped_node_table, bus))) {
354 pr_debug("%s() - skipping %pOF node\n", __func__, bus);
355 return 0;
356 }
357
358 if (of_node_check_flag(bus, OF_POPULATED_BUS)) {
359 pr_debug("%s() - skipping %pOF, already populated\n",
360 __func__, bus);
361 return 0;
362 }
363
364 auxdata = of_dev_lookup(lookup, bus);
365 if (auxdata) {
366 bus_id = auxdata->name;
367 platform_data = auxdata->platform_data;
368 }
369
370 if (of_device_is_compatible(bus, "arm,primecell")) {
371 /*
372 * Don't return an error here to keep compatibility with older
373 * device tree files.
374 */
375 of_amba_device_create(bus, bus_id, platform_data, parent);
376 return 0;
377 }
378
379 dev = of_platform_device_create_pdata(bus, bus_id, platform_data, parent);
380 if (!dev || !of_match_node(matches, bus))
381 return 0;
382
383 for_each_child_of_node(bus, child) {
384 pr_debug(" create child: %pOF\n", child);
385 rc = of_platform_bus_create(child, matches, lookup, &dev->dev, strict);
386 if (rc) {
387 of_node_put(child);
388 break;
389 }
390 }
391 of_node_set_flag(bus, OF_POPULATED_BUS);
392 return rc;
393 }
394
395 /**
396 * of_platform_bus_probe() - Probe the device-tree for platform buses
397 * @root: parent of the first level to probe or NULL for the root of the tree
398 * @matches: match table for bus nodes
399 * @parent: parent to hook devices from, NULL for toplevel
400 *
401 * Note that children of the provided root are not instantiated as devices
402 * unless the specified root itself matches the bus list and is not NULL.
403 */
of_platform_bus_probe(struct device_node * root,const struct of_device_id * matches,struct device * parent)404 int of_platform_bus_probe(struct device_node *root,
405 const struct of_device_id *matches,
406 struct device *parent)
407 {
408 struct device_node *child;
409 int rc = 0;
410
411 root = root ? of_node_get(root) : of_find_node_by_path("/");
412 if (!root)
413 return -EINVAL;
414
415 pr_debug("%s()\n", __func__);
416 pr_debug(" starting at: %pOF\n", root);
417
418 /* Do a self check of bus type, if there's a match, create children */
419 if (of_match_node(matches, root)) {
420 rc = of_platform_bus_create(root, matches, NULL, parent, false);
421 } else for_each_child_of_node(root, child) {
422 if (!of_match_node(matches, child))
423 continue;
424 rc = of_platform_bus_create(child, matches, NULL, parent, false);
425 if (rc) {
426 of_node_put(child);
427 break;
428 }
429 }
430
431 of_node_put(root);
432 return rc;
433 }
434 EXPORT_SYMBOL(of_platform_bus_probe);
435
436 /**
437 * of_platform_populate() - Populate platform_devices from device tree data
438 * @root: parent of the first level to probe or NULL for the root of the tree
439 * @matches: match table, NULL to use the default
440 * @lookup: auxdata table for matching id and platform_data with device nodes
441 * @parent: parent to hook devices from, NULL for toplevel
442 *
443 * Similar to of_platform_bus_probe(), this function walks the device tree
444 * and creates devices from nodes. It differs in that it follows the modern
445 * convention of requiring all device nodes to have a 'compatible' property,
446 * and it is suitable for creating devices which are children of the root
447 * node (of_platform_bus_probe will only create children of the root which
448 * are selected by the @matches argument).
449 *
450 * New board support should be using this function instead of
451 * of_platform_bus_probe().
452 *
453 * Return: 0 on success, < 0 on failure.
454 */
of_platform_populate(struct device_node * root,const struct of_device_id * matches,const struct of_dev_auxdata * lookup,struct device * parent)455 int of_platform_populate(struct device_node *root,
456 const struct of_device_id *matches,
457 const struct of_dev_auxdata *lookup,
458 struct device *parent)
459 {
460 struct device_node *child;
461 int rc = 0;
462
463 root = root ? of_node_get(root) : of_find_node_by_path("/");
464 if (!root)
465 return -EINVAL;
466
467 pr_debug("%s()\n", __func__);
468 pr_debug(" starting at: %pOF\n", root);
469
470 device_links_supplier_sync_state_pause();
471 for_each_child_of_node(root, child) {
472 rc = of_platform_bus_create(child, matches, lookup, parent, true);
473 if (rc) {
474 of_node_put(child);
475 break;
476 }
477 }
478 device_links_supplier_sync_state_resume();
479
480 of_node_set_flag(root, OF_POPULATED_BUS);
481
482 of_node_put(root);
483 return rc;
484 }
485 EXPORT_SYMBOL_GPL(of_platform_populate);
486
of_platform_default_populate(struct device_node * root,const struct of_dev_auxdata * lookup,struct device * parent)487 int of_platform_default_populate(struct device_node *root,
488 const struct of_dev_auxdata *lookup,
489 struct device *parent)
490 {
491 return of_platform_populate(root, of_default_bus_match_table, lookup,
492 parent);
493 }
494 EXPORT_SYMBOL_GPL(of_platform_default_populate);
495
496 static const struct of_device_id reserved_mem_matches[] = {
497 { .compatible = "phram" },
498 { .compatible = "qcom,rmtfs-mem" },
499 { .compatible = "qcom,cmd-db" },
500 { .compatible = "qcom,smem" },
501 { .compatible = "ramoops" },
502 { .compatible = "nvmem-rmem" },
503 { .compatible = "google,open-dice" },
504 {}
505 };
506
of_platform_default_populate_init(void)507 static int __init of_platform_default_populate_init(void)
508 {
509 struct device_node *node;
510
511 device_links_supplier_sync_state_pause();
512
513 if (!of_have_populated_dt())
514 return -ENODEV;
515
516 if (IS_ENABLED(CONFIG_PPC)) {
517 struct device_node *boot_display = NULL;
518 struct platform_device *dev;
519 int display_number = 0;
520 int ret;
521
522 /* Check if we have a MacOS display without a node spec */
523 if (of_property_present(of_chosen, "linux,bootx-noscreen")) {
524 /*
525 * The old code tried to work out which node was the MacOS
526 * display based on the address. I'm dropping that since the
527 * lack of a node spec only happens with old BootX versions
528 * (users can update) and with this code, they'll still get
529 * a display (just not the palette hacks).
530 */
531 dev = platform_device_alloc("bootx-noscreen", 0);
532 if (WARN_ON(!dev))
533 return -ENOMEM;
534 ret = platform_device_add(dev);
535 if (WARN_ON(ret)) {
536 platform_device_put(dev);
537 return ret;
538 }
539 }
540
541 /*
542 * For OF framebuffers, first create the device for the boot display,
543 * then for the other framebuffers. Only fail for the boot display;
544 * ignore errors for the rest.
545 */
546 for_each_node_by_type(node, "display") {
547 if (!of_get_property(node, "linux,opened", NULL) ||
548 !of_get_property(node, "linux,boot-display", NULL))
549 continue;
550 dev = of_platform_device_create(node, "of-display", NULL);
551 of_node_put(node);
552 if (WARN_ON(!dev))
553 return -ENOMEM;
554 boot_display = node;
555 display_number++;
556 break;
557 }
558 for_each_node_by_type(node, "display") {
559 char buf[14];
560 const char *of_display_format = "of-display.%d";
561
562 if (!of_get_property(node, "linux,opened", NULL) || node == boot_display)
563 continue;
564 ret = snprintf(buf, sizeof(buf), of_display_format, display_number++);
565 if (ret < sizeof(buf))
566 of_platform_device_create(node, buf, NULL);
567 }
568
569 } else {
570 /*
571 * Handle certain compatibles explicitly, since we don't want to create
572 * platform_devices for every node in /reserved-memory with a
573 * "compatible",
574 */
575 for_each_matching_node(node, reserved_mem_matches)
576 of_platform_device_create(node, NULL, NULL);
577
578 node = of_find_node_by_path("/firmware");
579 if (node) {
580 of_platform_populate(node, NULL, NULL, NULL);
581 of_node_put(node);
582 }
583
584 node = of_get_compatible_child(of_chosen, "simple-framebuffer");
585 if (node) {
586 /*
587 * Since a "simple-framebuffer" device is already added
588 * here, disable the Generic System Framebuffers (sysfb)
589 * to prevent it from registering another device for the
590 * system framebuffer later (e.g: using the screen_info
591 * data that may had been filled as well).
592 *
593 * This can happen for example on DT systems that do EFI
594 * booting and may provide a GOP handle to the EFI stub.
595 */
596 sysfb_disable();
597 of_platform_device_create(node, NULL, NULL);
598 of_node_put(node);
599 }
600
601 /* Populate everything else. */
602 of_platform_default_populate(NULL, NULL, NULL);
603 }
604
605 return 0;
606 }
607 arch_initcall_sync(of_platform_default_populate_init);
608
of_platform_sync_state_init(void)609 static int __init of_platform_sync_state_init(void)
610 {
611 device_links_supplier_sync_state_resume();
612 return 0;
613 }
614 late_initcall_sync(of_platform_sync_state_init);
615
of_platform_device_destroy(struct device * dev,void * data)616 int of_platform_device_destroy(struct device *dev, void *data)
617 {
618 /* Do not touch devices not populated from the device tree */
619 if (!dev->of_node || !of_node_check_flag(dev->of_node, OF_POPULATED))
620 return 0;
621
622 /* Recurse for any nodes that were treated as busses */
623 if (of_node_check_flag(dev->of_node, OF_POPULATED_BUS))
624 device_for_each_child(dev, NULL, of_platform_device_destroy);
625
626 of_node_clear_flag(dev->of_node, OF_POPULATED);
627 of_node_clear_flag(dev->of_node, OF_POPULATED_BUS);
628
629 if (dev->bus == &platform_bus_type)
630 platform_device_unregister(to_platform_device(dev));
631 #ifdef CONFIG_ARM_AMBA
632 else if (dev->bus == &amba_bustype)
633 amba_device_unregister(to_amba_device(dev));
634 #endif
635
636 return 0;
637 }
638 EXPORT_SYMBOL_GPL(of_platform_device_destroy);
639
640 /**
641 * of_platform_depopulate() - Remove devices populated from device tree
642 * @parent: device which children will be removed
643 *
644 * Complementary to of_platform_populate(), this function removes children
645 * of the given device (and, recursively, their children) that have been
646 * created from their respective device tree nodes (and only those,
647 * leaving others - eg. manually created - unharmed).
648 */
of_platform_depopulate(struct device * parent)649 void of_platform_depopulate(struct device *parent)
650 {
651 if (parent->of_node && of_node_check_flag(parent->of_node, OF_POPULATED_BUS)) {
652 device_for_each_child_reverse(parent, NULL, of_platform_device_destroy);
653 of_node_clear_flag(parent->of_node, OF_POPULATED_BUS);
654 }
655 }
656 EXPORT_SYMBOL_GPL(of_platform_depopulate);
657
devm_of_platform_populate_release(struct device * dev,void * res)658 static void devm_of_platform_populate_release(struct device *dev, void *res)
659 {
660 of_platform_depopulate(*(struct device **)res);
661 }
662
663 /**
664 * devm_of_platform_populate() - Populate platform_devices from device tree data
665 * @dev: device that requested to populate from device tree data
666 *
667 * Similar to of_platform_populate(), but will automatically call
668 * of_platform_depopulate() when the device is unbound from the bus.
669 *
670 * Return: 0 on success, < 0 on failure.
671 */
devm_of_platform_populate(struct device * dev)672 int devm_of_platform_populate(struct device *dev)
673 {
674 struct device **ptr;
675 int ret;
676
677 if (!dev)
678 return -EINVAL;
679
680 ptr = devres_alloc(devm_of_platform_populate_release,
681 sizeof(*ptr), GFP_KERNEL);
682 if (!ptr)
683 return -ENOMEM;
684
685 ret = of_platform_populate(dev->of_node, NULL, NULL, dev);
686 if (ret) {
687 devres_free(ptr);
688 } else {
689 *ptr = dev;
690 devres_add(dev, ptr);
691 }
692
693 return ret;
694 }
695 EXPORT_SYMBOL_GPL(devm_of_platform_populate);
696
devm_of_platform_match(struct device * dev,void * res,void * data)697 static int devm_of_platform_match(struct device *dev, void *res, void *data)
698 {
699 struct device **ptr = res;
700
701 if (!ptr) {
702 WARN_ON(!ptr);
703 return 0;
704 }
705
706 return *ptr == data;
707 }
708
709 /**
710 * devm_of_platform_depopulate() - Remove devices populated from device tree
711 * @dev: device that requested to depopulate from device tree data
712 *
713 * Complementary to devm_of_platform_populate(), this function removes children
714 * of the given device (and, recursively, their children) that have been
715 * created from their respective device tree nodes (and only those,
716 * leaving others - eg. manually created - unharmed).
717 */
devm_of_platform_depopulate(struct device * dev)718 void devm_of_platform_depopulate(struct device *dev)
719 {
720 int ret;
721
722 ret = devres_release(dev, devm_of_platform_populate_release,
723 devm_of_platform_match, dev);
724
725 WARN_ON(ret);
726 }
727 EXPORT_SYMBOL_GPL(devm_of_platform_depopulate);
728
729 #ifdef CONFIG_OF_DYNAMIC
of_platform_notify(struct notifier_block * nb,unsigned long action,void * arg)730 static int of_platform_notify(struct notifier_block *nb,
731 unsigned long action, void *arg)
732 {
733 struct of_reconfig_data *rd = arg;
734 struct platform_device *pdev_parent, *pdev;
735 bool children_left;
736
737 switch (of_reconfig_get_state_change(action, rd)) {
738 case OF_RECONFIG_CHANGE_ADD:
739 /* verify that the parent is a bus */
740 if (!of_node_check_flag(rd->dn->parent, OF_POPULATED_BUS))
741 return NOTIFY_OK; /* not for us */
742
743 /* already populated? (driver using of_populate manually) */
744 if (of_node_check_flag(rd->dn, OF_POPULATED))
745 return NOTIFY_OK;
746
747 /*
748 * Clear the flag before adding the device so that fw_devlink
749 * doesn't skip adding consumers to this device.
750 */
751 rd->dn->fwnode.flags &= ~FWNODE_FLAG_NOT_DEVICE;
752 /* pdev_parent may be NULL when no bus platform device */
753 pdev_parent = of_find_device_by_node(rd->dn->parent);
754 pdev = of_platform_device_create(rd->dn, NULL,
755 pdev_parent ? &pdev_parent->dev : NULL);
756 platform_device_put(pdev_parent);
757
758 if (pdev == NULL) {
759 pr_err("%s: failed to create for '%pOF'\n",
760 __func__, rd->dn);
761 /* of_platform_device_create tosses the error code */
762 return notifier_from_errno(-EINVAL);
763 }
764 break;
765
766 case OF_RECONFIG_CHANGE_REMOVE:
767
768 /* already depopulated? */
769 if (!of_node_check_flag(rd->dn, OF_POPULATED))
770 return NOTIFY_OK;
771
772 /* find our device by node */
773 pdev = of_find_device_by_node(rd->dn);
774 if (pdev == NULL)
775 return NOTIFY_OK; /* no? not meant for us */
776
777 /* unregister takes one ref away */
778 of_platform_device_destroy(&pdev->dev, &children_left);
779
780 /* and put the reference of the find */
781 platform_device_put(pdev);
782 break;
783 }
784
785 return NOTIFY_OK;
786 }
787
788 static struct notifier_block platform_of_notifier = {
789 .notifier_call = of_platform_notify,
790 };
791
of_platform_register_reconfig_notifier(void)792 void of_platform_register_reconfig_notifier(void)
793 {
794 WARN_ON(of_reconfig_notifier_register(&platform_of_notifier));
795 }
796 #endif /* CONFIG_OF_DYNAMIC */
797
798 #endif /* CONFIG_OF_ADDRESS */
799