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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_irq.h>
21#include <linux/of_platform.h>
22#include <linux/platform_device.h>
23
24const struct of_device_id of_default_bus_match_table[] = {
25 { .compatible = "simple-bus", },
26 { .compatible = "simple-mfd", },
27 { .compatible = "isa", },
28#ifdef CONFIG_ARM_AMBA
29 { .compatible = "arm,amba-bus", },
30#endif /* CONFIG_ARM_AMBA */
31 {} /* Empty terminated list */
32};
33
34static const struct of_device_id of_skipped_node_table[] = {
35 { .compatible = "operating-points-v2", },
36 {} /* Empty terminated list */
37};
38
39/**
40 * of_find_device_by_node - Find the platform_device associated with a node
41 * @np: Pointer to device tree node
42 *
43 * Takes a reference to the embedded struct device which needs to be dropped
44 * after use.
45 *
46 * Return: platform_device pointer, or NULL if not found
47 */
48struct platform_device *of_find_device_by_node(struct device_node *np)
49{
50 struct device *dev;
51
52 dev = bus_find_device_by_of_node(&platform_bus_type, np);
53 return dev ? to_platform_device(dev) : NULL;
54}
55EXPORT_SYMBOL(of_find_device_by_node);
56
57#ifdef CONFIG_OF_ADDRESS
58/*
59 * The following routines scan a subtree and registers a device for
60 * each applicable node.
61 *
62 * Note: sparc doesn't use these routines because it has a different
63 * mechanism for creating devices from device tree nodes.
64 */
65
66/**
67 * of_device_make_bus_id - Use the device node data to assign a unique name
68 * @dev: pointer to device structure that is linked to a device tree node
69 *
70 * This routine will first try using the translated bus address to
71 * derive a unique name. If it cannot, then it will prepend names from
72 * parent nodes until a unique name can be derived.
73 */
74static void of_device_make_bus_id(struct device *dev)
75{
76 struct device_node *node = dev->of_node;
77 const __be32 *reg;
78 u64 addr;
79
80 /* Construct the name, using parent nodes if necessary to ensure uniqueness */
81 while (node->parent) {
82 /*
83 * If the address can be translated, then that is as much
84 * uniqueness as we need. Make it the first component and return
85 */
86 reg = of_get_property(node, "reg", NULL);
87 if (reg && (addr = of_translate_address(node, reg)) != OF_BAD_ADDR) {
88 dev_set_name(dev, dev_name(dev) ? "%llx.%pOFn:%s" : "%llx.%pOFn",
89 addr, node, dev_name(dev));
90 return;
91 }
92
93 /* format arguments only used if dev_name() resolves to NULL */
94 dev_set_name(dev, dev_name(dev) ? "%s:%s" : "%s",
95 kbasename(node->full_name), dev_name(dev));
96 node = node->parent;
97 }
98}
99
100/**
101 * of_device_alloc - Allocate and initialize an of_device
102 * @np: device node to assign to device
103 * @bus_id: Name to assign to the device. May be null to use default name.
104 * @parent: Parent device.
105 */
106struct platform_device *of_device_alloc(struct device_node *np,
107 const char *bus_id,
108 struct device *parent)
109{
110 struct platform_device *dev;
111 int rc, i, num_reg = 0, num_irq;
112 struct resource *res, temp_res;
113
114 dev = platform_device_alloc("", PLATFORM_DEVID_NONE);
115 if (!dev)
116 return NULL;
117
118 /* count the io and irq resources */
119 while (of_address_to_resource(np, num_reg, &temp_res) == 0)
120 num_reg++;
121 num_irq = of_irq_count(np);
122
123 /* Populate the resource table */
124 if (num_irq || num_reg) {
125 res = kcalloc(num_irq + num_reg, sizeof(*res), GFP_KERNEL);
126 if (!res) {
127 platform_device_put(dev);
128 return NULL;
129 }
130
131 dev->num_resources = num_reg + num_irq;
132 dev->resource = res;
133 for (i = 0; i < num_reg; i++, res++) {
134 rc = of_address_to_resource(np, i, res);
135 WARN_ON(rc);
136 }
137 if (of_irq_to_resource_table(np, res, num_irq) != num_irq)
138 pr_debug("not all legacy IRQ resources mapped for %pOFn\n",
139 np);
140 }
141
142 dev->dev.of_node = of_node_get(np);
143 dev->dev.fwnode = &np->fwnode;
144 dev->dev.parent = parent ? : &platform_bus;
145
146 if (bus_id)
147 dev_set_name(&dev->dev, "%s", bus_id);
148 else
149 of_device_make_bus_id(&dev->dev);
150
151 return dev;
152}
153EXPORT_SYMBOL(of_device_alloc);
154
155/**
156 * of_platform_device_create_pdata - Alloc, initialize and register an of_device
157 * @np: pointer to node to create device for
158 * @bus_id: name to assign device
159 * @platform_data: pointer to populate platform_data pointer with
160 * @parent: Linux device model parent device.
161 *
162 * Return: Pointer to created platform device, or NULL if a device was not
163 * registered. Unavailable devices will not get registered.
164 */
165static struct platform_device *of_platform_device_create_pdata(
166 struct device_node *np,
167 const char *bus_id,
168 void *platform_data,
169 struct device *parent)
170{
171 struct platform_device *dev;
172
173 if (!of_device_is_available(np) ||
174 of_node_test_and_set_flag(np, OF_POPULATED))
175 return NULL;
176
177 dev = of_device_alloc(np, bus_id, parent);
178 if (!dev)
179 goto err_clear_flag;
180
181 dev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
182 if (!dev->dev.dma_mask)
183 dev->dev.dma_mask = &dev->dev.coherent_dma_mask;
184 dev->dev.bus = &platform_bus_type;
185 dev->dev.platform_data = platform_data;
186 of_msi_configure(&dev->dev, dev->dev.of_node);
187
188 if (of_device_add(dev) != 0) {
189 platform_device_put(dev);
190 goto err_clear_flag;
191 }
192
193 return dev;
194
195err_clear_flag:
196 of_node_clear_flag(np, OF_POPULATED);
197 return NULL;
198}
199
200/**
201 * of_platform_device_create - Alloc, initialize and register an of_device
202 * @np: pointer to node to create device for
203 * @bus_id: name to assign device
204 * @parent: Linux device model parent device.
205 *
206 * Return: Pointer to created platform device, or NULL if a device was not
207 * registered. Unavailable devices will not get registered.
208 */
209struct platform_device *of_platform_device_create(struct device_node *np,
210 const char *bus_id,
211 struct device *parent)
212{
213 return of_platform_device_create_pdata(np, bus_id, NULL, parent);
214}
215EXPORT_SYMBOL(of_platform_device_create);
216
217#ifdef CONFIG_ARM_AMBA
218static struct amba_device *of_amba_device_create(struct device_node *node,
219 const char *bus_id,
220 void *platform_data,
221 struct device *parent)
222{
223 struct amba_device *dev;
224 const void *prop;
225 int i, ret;
226
227 pr_debug("Creating amba device %pOF\n", node);
228
229 if (!of_device_is_available(node) ||
230 of_node_test_and_set_flag(node, OF_POPULATED))
231 return NULL;
232
233 dev = amba_device_alloc(NULL, 0, 0);
234 if (!dev)
235 goto err_clear_flag;
236
237 /* AMBA devices only support a single DMA mask */
238 dev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
239 dev->dev.dma_mask = &dev->dev.coherent_dma_mask;
240
241 /* setup generic device info */
242 dev->dev.of_node = of_node_get(node);
243 dev->dev.fwnode = &node->fwnode;
244 dev->dev.parent = parent ? : &platform_bus;
245 dev->dev.platform_data = platform_data;
246 if (bus_id)
247 dev_set_name(&dev->dev, "%s", bus_id);
248 else
249 of_device_make_bus_id(&dev->dev);
250
251 /* Allow the HW Peripheral ID to be overridden */
252 prop = of_get_property(node, "arm,primecell-periphid", NULL);
253 if (prop)
254 dev->periphid = of_read_ulong(prop, 1);
255
256 /* Decode the IRQs and address ranges */
257 for (i = 0; i < AMBA_NR_IRQS; i++)
258 dev->irq[i] = irq_of_parse_and_map(node, i);
259
260 ret = of_address_to_resource(node, 0, &dev->res);
261 if (ret) {
262 pr_err("amba: of_address_to_resource() failed (%d) for %pOF\n",
263 ret, node);
264 goto err_free;
265 }
266
267 ret = amba_device_add(dev, &iomem_resource);
268 if (ret) {
269 pr_err("amba_device_add() failed (%d) for %pOF\n",
270 ret, node);
271 goto err_free;
272 }
273
274 return dev;
275
276err_free:
277 amba_device_put(dev);
278err_clear_flag:
279 of_node_clear_flag(node, OF_POPULATED);
280 return NULL;
281}
282#else /* CONFIG_ARM_AMBA */
283static struct amba_device *of_amba_device_create(struct device_node *node,
284 const char *bus_id,
285 void *platform_data,
286 struct device *parent)
287{
288 return NULL;
289}
290#endif /* CONFIG_ARM_AMBA */
291
292/*
293 * of_dev_lookup() - Given a device node, lookup the preferred Linux name
294 */
295static const struct of_dev_auxdata *of_dev_lookup(const struct of_dev_auxdata *lookup,
296 struct device_node *np)
297{
298 const struct of_dev_auxdata *auxdata;
299 struct resource res;
300 int compatible = 0;
301
302 if (!lookup)
303 return NULL;
304
305 auxdata = lookup;
306 for (; auxdata->compatible; auxdata++) {
307 if (!of_device_is_compatible(np, auxdata->compatible))
308 continue;
309 compatible++;
310 if (!of_address_to_resource(np, 0, &res))
311 if (res.start != auxdata->phys_addr)
312 continue;
313 pr_debug("%pOF: devname=%s\n", np, auxdata->name);
314 return auxdata;
315 }
316
317 if (!compatible)
318 return NULL;
319
320 /* Try compatible match if no phys_addr and name are specified */
321 auxdata = lookup;
322 for (; auxdata->compatible; auxdata++) {
323 if (!of_device_is_compatible(np, auxdata->compatible))
324 continue;
325 if (!auxdata->phys_addr && !auxdata->name) {
326 pr_debug("%pOF: compatible match\n", np);
327 return auxdata;
328 }
329 }
330
331 return NULL;
332}
333
334/**
335 * of_platform_bus_create() - Create a device for a node and its children.
336 * @bus: device node of the bus to instantiate
337 * @matches: match table for bus nodes
338 * @lookup: auxdata table for matching id and platform_data with device nodes
339 * @parent: parent for new device, or NULL for top level.
340 * @strict: require compatible property
341 *
342 * Creates a platform_device for the provided device_node, and optionally
343 * recursively create devices for all the child nodes.
344 */
345static int of_platform_bus_create(struct device_node *bus,
346 const struct of_device_id *matches,
347 const struct of_dev_auxdata *lookup,
348 struct device *parent, bool strict)
349{
350 const struct of_dev_auxdata *auxdata;
351 struct device_node *child;
352 struct platform_device *dev;
353 const char *bus_id = NULL;
354 void *platform_data = NULL;
355 int rc = 0;
356
357 /* Make sure it has a compatible property */
358 if (strict && (!of_get_property(bus, "compatible", NULL))) {
359 pr_debug("%s() - skipping %pOF, no compatible prop\n",
360 __func__, bus);
361 return 0;
362 }
363
364 /* Skip nodes for which we don't want to create devices */
365 if (unlikely(of_match_node(of_skipped_node_table, bus))) {
366 pr_debug("%s() - skipping %pOF node\n", __func__, bus);
367 return 0;
368 }
369
370 if (of_node_check_flag(bus, OF_POPULATED_BUS)) {
371 pr_debug("%s() - skipping %pOF, already populated\n",
372 __func__, bus);
373 return 0;
374 }
375
376 auxdata = of_dev_lookup(lookup, bus);
377 if (auxdata) {
378 bus_id = auxdata->name;
379 platform_data = auxdata->platform_data;
380 }
381
382 if (of_device_is_compatible(bus, "arm,primecell")) {
383 /*
384 * Don't return an error here to keep compatibility with older
385 * device tree files.
386 */
387 of_amba_device_create(bus, bus_id, platform_data, parent);
388 return 0;
389 }
390
391 dev = of_platform_device_create_pdata(bus, bus_id, platform_data, parent);
392 if (!dev || !of_match_node(matches, bus))
393 return 0;
394
395 for_each_child_of_node(bus, child) {
396 pr_debug(" create child: %pOF\n", child);
397 rc = of_platform_bus_create(child, matches, lookup, &dev->dev, strict);
398 if (rc) {
399 of_node_put(child);
400 break;
401 }
402 }
403 of_node_set_flag(bus, OF_POPULATED_BUS);
404 return rc;
405}
406
407/**
408 * of_platform_bus_probe() - Probe the device-tree for platform buses
409 * @root: parent of the first level to probe or NULL for the root of the tree
410 * @matches: match table for bus nodes
411 * @parent: parent to hook devices from, NULL for toplevel
412 *
413 * Note that children of the provided root are not instantiated as devices
414 * unless the specified root itself matches the bus list and is not NULL.
415 */
416int of_platform_bus_probe(struct device_node *root,
417 const struct of_device_id *matches,
418 struct device *parent)
419{
420 struct device_node *child;
421 int rc = 0;
422
423 root = root ? of_node_get(root) : of_find_node_by_path("/");
424 if (!root)
425 return -EINVAL;
426
427 pr_debug("%s()\n", __func__);
428 pr_debug(" starting at: %pOF\n", root);
429
430 /* Do a self check of bus type, if there's a match, create children */
431 if (of_match_node(matches, root)) {
432 rc = of_platform_bus_create(root, matches, NULL, parent, false);
433 } else for_each_child_of_node(root, child) {
434 if (!of_match_node(matches, child))
435 continue;
436 rc = of_platform_bus_create(child, matches, NULL, parent, false);
437 if (rc) {
438 of_node_put(child);
439 break;
440 }
441 }
442
443 of_node_put(root);
444 return rc;
445}
446EXPORT_SYMBOL(of_platform_bus_probe);
447
448/**
449 * of_platform_populate() - Populate platform_devices from device tree data
450 * @root: parent of the first level to probe or NULL for the root of the tree
451 * @matches: match table, NULL to use the default
452 * @lookup: auxdata table for matching id and platform_data with device nodes
453 * @parent: parent to hook devices from, NULL for toplevel
454 *
455 * Similar to of_platform_bus_probe(), this function walks the device tree
456 * and creates devices from nodes. It differs in that it follows the modern
457 * convention of requiring all device nodes to have a 'compatible' property,
458 * and it is suitable for creating devices which are children of the root
459 * node (of_platform_bus_probe will only create children of the root which
460 * are selected by the @matches argument).
461 *
462 * New board support should be using this function instead of
463 * of_platform_bus_probe().
464 *
465 * Return: 0 on success, < 0 on failure.
466 */
467int of_platform_populate(struct device_node *root,
468 const struct of_device_id *matches,
469 const struct of_dev_auxdata *lookup,
470 struct device *parent)
471{
472 struct device_node *child;
473 int rc = 0;
474
475 root = root ? of_node_get(root) : of_find_node_by_path("/");
476 if (!root)
477 return -EINVAL;
478
479 pr_debug("%s()\n", __func__);
480 pr_debug(" starting at: %pOF\n", root);
481
482 device_links_supplier_sync_state_pause();
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 device_links_supplier_sync_state_resume();
491
492 of_node_set_flag(root, OF_POPULATED_BUS);
493
494 of_node_put(root);
495 return rc;
496}
497EXPORT_SYMBOL_GPL(of_platform_populate);
498
499int of_platform_default_populate(struct device_node *root,
500 const struct of_dev_auxdata *lookup,
501 struct device *parent)
502{
503 return of_platform_populate(root, of_default_bus_match_table, lookup,
504 parent);
505}
506EXPORT_SYMBOL_GPL(of_platform_default_populate);
507
508#ifndef CONFIG_PPC
509static const struct of_device_id reserved_mem_matches[] = {
510 { .compatible = "qcom,rmtfs-mem" },
511 { .compatible = "qcom,cmd-db" },
512 { .compatible = "ramoops" },
513 { .compatible = "nvmem-rmem" },
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 of_platform_default_populate(NULL, NULL, NULL);
542
543 return 0;
544}
545arch_initcall_sync(of_platform_default_populate_init);
546
547static int __init of_platform_sync_state_init(void)
548{
549 device_links_supplier_sync_state_resume();
550 return 0;
551}
552late_initcall_sync(of_platform_sync_state_init);
553#endif
554
555int of_platform_device_destroy(struct device *dev, void *data)
556{
557 /* Do not touch devices not populated from the device tree */
558 if (!dev->of_node || !of_node_check_flag(dev->of_node, OF_POPULATED))
559 return 0;
560
561 /* Recurse for any nodes that were treated as busses */
562 if (of_node_check_flag(dev->of_node, OF_POPULATED_BUS))
563 device_for_each_child(dev, NULL, of_platform_device_destroy);
564
565 of_node_clear_flag(dev->of_node, OF_POPULATED);
566 of_node_clear_flag(dev->of_node, OF_POPULATED_BUS);
567
568 if (dev->bus == &platform_bus_type)
569 platform_device_unregister(to_platform_device(dev));
570#ifdef CONFIG_ARM_AMBA
571 else if (dev->bus == &amba_bustype)
572 amba_device_unregister(to_amba_device(dev));
573#endif
574
575 return 0;
576}
577EXPORT_SYMBOL_GPL(of_platform_device_destroy);
578
579/**
580 * of_platform_depopulate() - Remove devices populated from device tree
581 * @parent: device which children will be removed
582 *
583 * Complementary to of_platform_populate(), this function removes children
584 * of the given device (and, recurrently, their children) that have been
585 * created from their respective device tree nodes (and only those,
586 * leaving others - eg. manually created - unharmed).
587 */
588void of_platform_depopulate(struct device *parent)
589{
590 if (parent->of_node && of_node_check_flag(parent->of_node, OF_POPULATED_BUS)) {
591 device_for_each_child_reverse(parent, NULL, of_platform_device_destroy);
592 of_node_clear_flag(parent->of_node, OF_POPULATED_BUS);
593 }
594}
595EXPORT_SYMBOL_GPL(of_platform_depopulate);
596
597static void devm_of_platform_populate_release(struct device *dev, void *res)
598{
599 of_platform_depopulate(*(struct device **)res);
600}
601
602/**
603 * devm_of_platform_populate() - Populate platform_devices from device tree data
604 * @dev: device that requested to populate from device tree data
605 *
606 * Similar to of_platform_populate(), but will automatically call
607 * of_platform_depopulate() when the device is unbound from the bus.
608 *
609 * Return: 0 on success, < 0 on failure.
610 */
611int devm_of_platform_populate(struct device *dev)
612{
613 struct device **ptr;
614 int ret;
615
616 if (!dev)
617 return -EINVAL;
618
619 ptr = devres_alloc(devm_of_platform_populate_release,
620 sizeof(*ptr), GFP_KERNEL);
621 if (!ptr)
622 return -ENOMEM;
623
624 ret = of_platform_populate(dev->of_node, NULL, NULL, dev);
625 if (ret) {
626 devres_free(ptr);
627 } else {
628 *ptr = dev;
629 devres_add(dev, ptr);
630 }
631
632 return ret;
633}
634EXPORT_SYMBOL_GPL(devm_of_platform_populate);
635
636static int devm_of_platform_match(struct device *dev, void *res, void *data)
637{
638 struct device **ptr = res;
639
640 if (!ptr) {
641 WARN_ON(!ptr);
642 return 0;
643 }
644
645 return *ptr == data;
646}
647
648/**
649 * devm_of_platform_depopulate() - Remove devices populated from device tree
650 * @dev: device that requested to depopulate from device tree data
651 *
652 * Complementary to devm_of_platform_populate(), this function removes children
653 * of the given device (and, recurrently, their children) that have been
654 * created from their respective device tree nodes (and only those,
655 * leaving others - eg. manually created - unharmed).
656 */
657void devm_of_platform_depopulate(struct device *dev)
658{
659 int ret;
660
661 ret = devres_release(dev, devm_of_platform_populate_release,
662 devm_of_platform_match, dev);
663
664 WARN_ON(ret);
665}
666EXPORT_SYMBOL_GPL(devm_of_platform_depopulate);
667
668#ifdef CONFIG_OF_DYNAMIC
669static int of_platform_notify(struct notifier_block *nb,
670 unsigned long action, void *arg)
671{
672 struct of_reconfig_data *rd = arg;
673 struct platform_device *pdev_parent, *pdev;
674 bool children_left;
675
676 switch (of_reconfig_get_state_change(action, rd)) {
677 case OF_RECONFIG_CHANGE_ADD:
678 /* verify that the parent is a bus */
679 if (!of_node_check_flag(rd->dn->parent, OF_POPULATED_BUS))
680 return NOTIFY_OK; /* not for us */
681
682 /* already populated? (driver using of_populate manually) */
683 if (of_node_check_flag(rd->dn, OF_POPULATED))
684 return NOTIFY_OK;
685
686 /* pdev_parent may be NULL when no bus platform device */
687 pdev_parent = of_find_device_by_node(rd->dn->parent);
688 pdev = of_platform_device_create(rd->dn, NULL,
689 pdev_parent ? &pdev_parent->dev : NULL);
690 platform_device_put(pdev_parent);
691
692 if (pdev == NULL) {
693 pr_err("%s: failed to create for '%pOF'\n",
694 __func__, rd->dn);
695 /* of_platform_device_create tosses the error code */
696 return notifier_from_errno(-EINVAL);
697 }
698 break;
699
700 case OF_RECONFIG_CHANGE_REMOVE:
701
702 /* already depopulated? */
703 if (!of_node_check_flag(rd->dn, OF_POPULATED))
704 return NOTIFY_OK;
705
706 /* find our device by node */
707 pdev = of_find_device_by_node(rd->dn);
708 if (pdev == NULL)
709 return NOTIFY_OK; /* no? not meant for us */
710
711 /* unregister takes one ref away */
712 of_platform_device_destroy(&pdev->dev, &children_left);
713
714 /* and put the reference of the find */
715 platform_device_put(pdev);
716 break;
717 }
718
719 return NOTIFY_OK;
720}
721
722static struct notifier_block platform_of_notifier = {
723 .notifier_call = of_platform_notify,
724};
725
726void of_platform_register_reconfig_notifier(void)
727{
728 WARN_ON(of_reconfig_notifier_register(&platform_of_notifier));
729}
730#endif /* CONFIG_OF_DYNAMIC */
731
732#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#include <linux/errno.h>
15#include <linux/module.h>
16#include <linux/amba/bus.h>
17#include <linux/device.h>
18#include <linux/dma-mapping.h>
19#include <linux/slab.h>
20#include <linux/of_address.h>
21#include <linux/of_device.h>
22#include <linux/of_irq.h>
23#include <linux/of_platform.h>
24#include <linux/platform_device.h>
25
26const struct of_device_id of_default_bus_match_table[] = {
27 { .compatible = "simple-bus", },
28#ifdef CONFIG_ARM_AMBA
29 { .compatible = "arm,amba-bus", },
30#endif /* CONFIG_ARM_AMBA */
31 {} /* Empty terminated list */
32};
33
34static int of_dev_node_match(struct device *dev, void *data)
35{
36 return dev->of_node == data;
37}
38
39/**
40 * of_find_device_by_node - Find the platform_device associated with a node
41 * @np: Pointer to device tree node
42 *
43 * Returns platform_device pointer, or NULL if not found
44 */
45struct platform_device *of_find_device_by_node(struct device_node *np)
46{
47 struct device *dev;
48
49 dev = bus_find_device(&platform_bus_type, NULL, np, of_dev_node_match);
50 return dev ? to_platform_device(dev) : NULL;
51}
52EXPORT_SYMBOL(of_find_device_by_node);
53
54#if defined(CONFIG_PPC_DCR)
55#include <asm/dcr.h>
56#endif
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 either the dcr-reg or the reg property
72 * value to derive a unique name. As a last resort it will use the node
73 * name followed by a unique number.
74 */
75void of_device_make_bus_id(struct device *dev)
76{
77 static atomic_t bus_no_reg_magic;
78 struct device_node *node = dev->of_node;
79 const __be32 *reg;
80 u64 addr;
81 const __be32 *addrp;
82 int magic;
83
84#ifdef CONFIG_PPC_DCR
85 /*
86 * If it's a DCR based device, use 'd' for native DCRs
87 * and 'D' for MMIO DCRs.
88 */
89 reg = of_get_property(node, "dcr-reg", NULL);
90 if (reg) {
91#ifdef CONFIG_PPC_DCR_NATIVE
92 dev_set_name(dev, "d%x.%s", *reg, node->name);
93#else /* CONFIG_PPC_DCR_NATIVE */
94 u64 addr = of_translate_dcr_address(node, *reg, NULL);
95 if (addr != OF_BAD_ADDR) {
96 dev_set_name(dev, "D%llx.%s",
97 (unsigned long long)addr, node->name);
98 return;
99 }
100#endif /* !CONFIG_PPC_DCR_NATIVE */
101 }
102#endif /* CONFIG_PPC_DCR */
103
104 /*
105 * For MMIO, get the physical address
106 */
107 reg = of_get_property(node, "reg", NULL);
108 if (reg) {
109 if (of_can_translate_address(node)) {
110 addr = of_translate_address(node, reg);
111 } else {
112 addrp = of_get_address(node, 0, NULL, NULL);
113 if (addrp)
114 addr = of_read_number(addrp, 1);
115 else
116 addr = OF_BAD_ADDR;
117 }
118 if (addr != OF_BAD_ADDR) {
119 dev_set_name(dev, "%llx.%s",
120 (unsigned long long)addr, node->name);
121 return;
122 }
123 }
124
125 /*
126 * No BusID, use the node name and add a globally incremented
127 * counter (and pray...)
128 */
129 magic = atomic_add_return(1, &bus_no_reg_magic);
130 dev_set_name(dev, "%s.%d", node->name, magic - 1);
131}
132
133/**
134 * of_device_alloc - Allocate and initialize an of_device
135 * @np: device node to assign to device
136 * @bus_id: Name to assign to the device. May be null to use default name.
137 * @parent: Parent device.
138 */
139struct platform_device *of_device_alloc(struct device_node *np,
140 const char *bus_id,
141 struct device *parent)
142{
143 struct platform_device *dev;
144 int rc, i, num_reg = 0, num_irq;
145 struct resource *res, temp_res;
146
147 dev = platform_device_alloc("", -1);
148 if (!dev)
149 return NULL;
150
151 /* count the io and irq resources */
152 if (of_can_translate_address(np))
153 while (of_address_to_resource(np, num_reg, &temp_res) == 0)
154 num_reg++;
155 num_irq = of_irq_count(np);
156
157 /* Populate the resource table */
158 if (num_irq || num_reg) {
159 res = kzalloc(sizeof(*res) * (num_irq + num_reg), GFP_KERNEL);
160 if (!res) {
161 platform_device_put(dev);
162 return NULL;
163 }
164
165 dev->num_resources = num_reg + num_irq;
166 dev->resource = res;
167 for (i = 0; i < num_reg; i++, res++) {
168 rc = of_address_to_resource(np, i, res);
169 WARN_ON(rc);
170 }
171 if (of_irq_to_resource_table(np, res, num_irq) != num_irq)
172 pr_debug("not all legacy IRQ resources mapped for %s\n",
173 np->name);
174 }
175
176 dev->dev.of_node = of_node_get(np);
177#if defined(CONFIG_MICROBLAZE)
178 dev->dev.dma_mask = &dev->archdata.dma_mask;
179#endif
180 dev->dev.parent = parent;
181
182 if (bus_id)
183 dev_set_name(&dev->dev, "%s", bus_id);
184 else
185 of_device_make_bus_id(&dev->dev);
186
187 return dev;
188}
189EXPORT_SYMBOL(of_device_alloc);
190
191/**
192 * of_platform_device_create_pdata - Alloc, initialize and register an of_device
193 * @np: pointer to node to create device for
194 * @bus_id: name to assign device
195 * @platform_data: pointer to populate platform_data pointer with
196 * @parent: Linux device model parent device.
197 *
198 * Returns pointer to created platform device, or NULL if a device was not
199 * registered. Unavailable devices will not get registered.
200 */
201static struct platform_device *of_platform_device_create_pdata(
202 struct device_node *np,
203 const char *bus_id,
204 void *platform_data,
205 struct device *parent)
206{
207 struct platform_device *dev;
208
209 if (!of_device_is_available(np))
210 return NULL;
211
212 dev = of_device_alloc(np, bus_id, parent);
213 if (!dev)
214 return NULL;
215
216#if defined(CONFIG_MICROBLAZE)
217 dev->archdata.dma_mask = 0xffffffffUL;
218#endif
219 dev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
220 if (!dev->dev.dma_mask)
221 dev->dev.dma_mask = &dev->dev.coherent_dma_mask;
222 dev->dev.bus = &platform_bus_type;
223 dev->dev.platform_data = platform_data;
224
225 /* We do not fill the DMA ops for platform devices by default.
226 * This is currently the responsibility of the platform code
227 * to do such, possibly using a device notifier
228 */
229
230 if (of_device_add(dev) != 0) {
231 platform_device_put(dev);
232 return NULL;
233 }
234
235 return dev;
236}
237
238/**
239 * of_platform_device_create - Alloc, initialize and register an of_device
240 * @np: pointer to node to create device for
241 * @bus_id: name to assign device
242 * @parent: Linux device model parent device.
243 *
244 * Returns pointer to created platform device, or NULL if a device was not
245 * registered. Unavailable devices will not get registered.
246 */
247struct platform_device *of_platform_device_create(struct device_node *np,
248 const char *bus_id,
249 struct device *parent)
250{
251 return of_platform_device_create_pdata(np, bus_id, NULL, parent);
252}
253EXPORT_SYMBOL(of_platform_device_create);
254
255#ifdef CONFIG_ARM_AMBA
256static struct amba_device *of_amba_device_create(struct device_node *node,
257 const char *bus_id,
258 void *platform_data,
259 struct device *parent)
260{
261 struct amba_device *dev;
262 const void *prop;
263 int i, ret;
264
265 pr_debug("Creating amba device %s\n", node->full_name);
266
267 if (!of_device_is_available(node))
268 return NULL;
269
270 dev = amba_device_alloc(NULL, 0, 0);
271 if (!dev) {
272 pr_err("%s(): amba_device_alloc() failed for %s\n",
273 __func__, node->full_name);
274 return NULL;
275 }
276
277 /* setup generic device info */
278 dev->dev.coherent_dma_mask = ~0;
279 dev->dev.of_node = of_node_get(node);
280 dev->dev.parent = parent;
281 dev->dev.platform_data = platform_data;
282 if (bus_id)
283 dev_set_name(&dev->dev, "%s", bus_id);
284 else
285 of_device_make_bus_id(&dev->dev);
286
287 /* Allow the HW Peripheral ID to be overridden */
288 prop = of_get_property(node, "arm,primecell-periphid", NULL);
289 if (prop)
290 dev->periphid = of_read_ulong(prop, 1);
291
292 /* Decode the IRQs and address ranges */
293 for (i = 0; i < AMBA_NR_IRQS; i++)
294 dev->irq[i] = irq_of_parse_and_map(node, i);
295
296 ret = of_address_to_resource(node, 0, &dev->res);
297 if (ret) {
298 pr_err("%s(): of_address_to_resource() failed (%d) for %s\n",
299 __func__, ret, node->full_name);
300 goto err_free;
301 }
302
303 ret = amba_device_add(dev, &iomem_resource);
304 if (ret) {
305 pr_err("%s(): amba_device_add() failed (%d) for %s\n",
306 __func__, ret, node->full_name);
307 goto err_free;
308 }
309
310 return dev;
311
312err_free:
313 amba_device_put(dev);
314 return NULL;
315}
316#else /* CONFIG_ARM_AMBA */
317static struct amba_device *of_amba_device_create(struct device_node *node,
318 const char *bus_id,
319 void *platform_data,
320 struct device *parent)
321{
322 return NULL;
323}
324#endif /* CONFIG_ARM_AMBA */
325
326/**
327 * of_devname_lookup() - Given a device node, lookup the preferred Linux name
328 */
329static const struct of_dev_auxdata *of_dev_lookup(const struct of_dev_auxdata *lookup,
330 struct device_node *np)
331{
332 struct resource res;
333
334 if (!lookup)
335 return NULL;
336
337 for(; lookup->compatible != NULL; lookup++) {
338 if (!of_device_is_compatible(np, lookup->compatible))
339 continue;
340 if (!of_address_to_resource(np, 0, &res))
341 if (res.start != lookup->phys_addr)
342 continue;
343 pr_debug("%s: devname=%s\n", np->full_name, lookup->name);
344 return lookup;
345 }
346
347 return NULL;
348}
349
350/**
351 * of_platform_bus_create() - Create a device for a node and its children.
352 * @bus: device node of the bus to instantiate
353 * @matches: match table for bus nodes
354 * @lookup: auxdata table for matching id and platform_data with device nodes
355 * @parent: parent for new device, or NULL for top level.
356 * @strict: require compatible property
357 *
358 * Creates a platform_device for the provided device_node, and optionally
359 * recursively create devices for all the child nodes.
360 */
361static int of_platform_bus_create(struct device_node *bus,
362 const struct of_device_id *matches,
363 const struct of_dev_auxdata *lookup,
364 struct device *parent, bool strict)
365{
366 const struct of_dev_auxdata *auxdata;
367 struct device_node *child;
368 struct platform_device *dev;
369 const char *bus_id = NULL;
370 void *platform_data = NULL;
371 int rc = 0;
372
373 /* Make sure it has a compatible property */
374 if (strict && (!of_get_property(bus, "compatible", NULL))) {
375 pr_debug("%s() - skipping %s, no compatible prop\n",
376 __func__, bus->full_name);
377 return 0;
378 }
379
380 auxdata = of_dev_lookup(lookup, bus);
381 if (auxdata) {
382 bus_id = auxdata->name;
383 platform_data = auxdata->platform_data;
384 }
385
386 if (of_device_is_compatible(bus, "arm,primecell")) {
387 /*
388 * Don't return an error here to keep compatibility with older
389 * device tree files.
390 */
391 of_amba_device_create(bus, bus_id, platform_data, parent);
392 return 0;
393 }
394
395 dev = of_platform_device_create_pdata(bus, bus_id, platform_data, parent);
396 if (!dev || !of_match_node(matches, bus))
397 return 0;
398
399 for_each_child_of_node(bus, child) {
400 pr_debug(" create child: %s\n", child->full_name);
401 rc = of_platform_bus_create(child, matches, lookup, &dev->dev, strict);
402 if (rc) {
403 of_node_put(child);
404 break;
405 }
406 }
407 return rc;
408}
409
410/**
411 * of_platform_bus_probe() - Probe the device-tree for platform buses
412 * @root: parent of the first level to probe or NULL for the root of the tree
413 * @matches: match table for bus nodes
414 * @parent: parent to hook devices from, NULL for toplevel
415 *
416 * Note that children of the provided root are not instantiated as devices
417 * unless the specified root itself matches the bus list and is not NULL.
418 */
419int of_platform_bus_probe(struct device_node *root,
420 const struct of_device_id *matches,
421 struct device *parent)
422{
423 struct device_node *child;
424 int rc = 0;
425
426 root = root ? of_node_get(root) : of_find_node_by_path("/");
427 if (!root)
428 return -EINVAL;
429
430 pr_debug("of_platform_bus_probe()\n");
431 pr_debug(" starting at: %s\n", root->full_name);
432
433 /* Do a self check of bus type, if there's a match, create children */
434 if (of_match_node(matches, root)) {
435 rc = of_platform_bus_create(root, matches, NULL, parent, false);
436 } else for_each_child_of_node(root, child) {
437 if (!of_match_node(matches, child))
438 continue;
439 rc = of_platform_bus_create(child, matches, NULL, parent, false);
440 if (rc)
441 break;
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 for_each_child_of_node(root, child) {
481 rc = of_platform_bus_create(child, matches, lookup, parent, true);
482 if (rc)
483 break;
484 }
485
486 of_node_put(root);
487 return rc;
488}
489EXPORT_SYMBOL_GPL(of_platform_populate);
490#endif /* CONFIG_OF_ADDRESS */