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