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