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