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v5.14.15
  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 */
v4.17
  1// SPDX-License-Identifier: GPL-2.0+
  2/*
  3 *    Copyright (C) 2006 Benjamin Herrenschmidt, IBM Corp.
  4 *			 <benh@kernel.crashing.org>
  5 *    and		 Arnd Bergmann, IBM Corp.
  6 *    Merged from powerpc/kernel/of_platform.c and
  7 *    sparc{,64}/kernel/of_device.c by Stephen Rothwell
  8 */
  9
 10#define pr_fmt(fmt)	"OF: " fmt
 11
 12#include <linux/errno.h>
 13#include <linux/module.h>
 14#include <linux/amba/bus.h>
 15#include <linux/device.h>
 16#include <linux/dma-mapping.h>
 17#include <linux/slab.h>
 18#include <linux/of_address.h>
 19#include <linux/of_device.h>
 20#include <linux/of_iommu.h>
 21#include <linux/of_irq.h>
 22#include <linux/of_platform.h>
 23#include <linux/platform_device.h>
 24
 25const struct of_device_id of_default_bus_match_table[] = {
 26	{ .compatible = "simple-bus", },
 27	{ .compatible = "simple-mfd", },
 28	{ .compatible = "isa", },
 29#ifdef CONFIG_ARM_AMBA
 30	{ .compatible = "arm,amba-bus", },
 31#endif /* CONFIG_ARM_AMBA */
 32	{} /* Empty terminated list */
 33};
 34
 35static int of_dev_node_match(struct device *dev, void *data)
 36{
 37	return dev->of_node == data;
 38}
 39
 40/**
 41 * of_find_device_by_node - Find the platform_device associated with a node
 42 * @np: Pointer to device tree node
 43 *
 44 * Takes a reference to the embedded struct device which needs to be dropped
 45 * after use.
 46 *
 47 * Returns platform_device pointer, or NULL if not found
 48 */
 49struct platform_device *of_find_device_by_node(struct device_node *np)
 50{
 51	struct device *dev;
 52
 53	dev = bus_find_device(&platform_bus_type, NULL, np, of_dev_node_match);
 54	return dev ? to_platform_device(dev) : NULL;
 55}
 56EXPORT_SYMBOL(of_find_device_by_node);
 57
 58#ifdef CONFIG_OF_ADDRESS
 59/*
 60 * The following routines scan a subtree and registers a device for
 61 * each applicable node.
 62 *
 63 * Note: sparc doesn't use these routines because it has a different
 64 * mechanism for creating devices from device tree nodes.
 65 */
 66
 67/**
 68 * of_device_make_bus_id - Use the device node data to assign a unique name
 69 * @dev: pointer to device structure that is linked to a device tree node
 70 *
 71 * This routine will first try using the translated bus address to
 72 * derive a unique name. If it cannot, then it will prepend names from
 73 * parent nodes until a unique name can be derived.
 74 */
 75static void of_device_make_bus_id(struct device *dev)
 76{
 77	struct device_node *node = dev->of_node;
 78	const __be32 *reg;
 79	u64 addr;
 80
 81	/* Construct the name, using parent nodes if necessary to ensure uniqueness */
 82	while (node->parent) {
 83		/*
 84		 * If the address can be translated, then that is as much
 85		 * uniqueness as we need. Make it the first component and return
 86		 */
 87		reg = of_get_property(node, "reg", NULL);
 88		if (reg && (addr = of_translate_address(node, reg)) != OF_BAD_ADDR) {
 89			dev_set_name(dev, dev_name(dev) ? "%llx.%s:%s" : "%llx.%s",
 90				     (unsigned long long)addr, node->name,
 91				     dev_name(dev));
 92			return;
 93		}
 94
 95		/* format arguments only used if dev_name() resolves to NULL */
 96		dev_set_name(dev, dev_name(dev) ? "%s:%s" : "%s",
 97			     kbasename(node->full_name), dev_name(dev));
 98		node = node->parent;
 99	}
100}
101
102/**
103 * of_device_alloc - Allocate and initialize an of_device
104 * @np: device node to assign to device
105 * @bus_id: Name to assign to the device.  May be null to use default name.
106 * @parent: Parent device.
107 */
108struct platform_device *of_device_alloc(struct device_node *np,
109				  const char *bus_id,
110				  struct device *parent)
111{
112	struct platform_device *dev;
113	int rc, i, num_reg = 0, num_irq;
114	struct resource *res, temp_res;
115
116	dev = platform_device_alloc("", PLATFORM_DEVID_NONE);
117	if (!dev)
118		return NULL;
119
120	/* count the io and irq resources */
121	while (of_address_to_resource(np, num_reg, &temp_res) == 0)
122		num_reg++;
123	num_irq = of_irq_count(np);
124
125	/* Populate the resource table */
126	if (num_irq || num_reg) {
127		res = kzalloc(sizeof(*res) * (num_irq + num_reg), GFP_KERNEL);
128		if (!res) {
129			platform_device_put(dev);
130			return NULL;
131		}
132
133		dev->num_resources = num_reg + num_irq;
134		dev->resource = res;
135		for (i = 0; i < num_reg; i++, res++) {
136			rc = of_address_to_resource(np, i, res);
137			WARN_ON(rc);
138		}
139		if (of_irq_to_resource_table(np, res, num_irq) != num_irq)
140			pr_debug("not all legacy IRQ resources mapped for %s\n",
141				 np->name);
142	}
143
144	dev->dev.of_node = of_node_get(np);
145	dev->dev.fwnode = &np->fwnode;
146	dev->dev.parent = parent ? : &platform_bus;
147
148	if (bus_id)
149		dev_set_name(&dev->dev, "%s", bus_id);
150	else
151		of_device_make_bus_id(&dev->dev);
152
153	return dev;
154}
155EXPORT_SYMBOL(of_device_alloc);
156
157/**
158 * of_platform_device_create_pdata - Alloc, initialize and register an of_device
159 * @np: pointer to node to create device for
160 * @bus_id: name to assign device
161 * @platform_data: pointer to populate platform_data pointer with
162 * @parent: Linux device model parent device.
163 *
164 * Returns pointer to created platform device, or NULL if a device was not
165 * registered.  Unavailable devices will not get registered.
166 */
167static struct platform_device *of_platform_device_create_pdata(
168					struct device_node *np,
169					const char *bus_id,
170					void *platform_data,
171					struct device *parent)
172{
173	struct platform_device *dev;
174
175	if (!of_device_is_available(np) ||
176	    of_node_test_and_set_flag(np, OF_POPULATED))
177		return NULL;
178
179	dev = of_device_alloc(np, bus_id, parent);
180	if (!dev)
181		goto err_clear_flag;
182
 
 
 
183	dev->dev.bus = &platform_bus_type;
184	dev->dev.platform_data = platform_data;
185	of_msi_configure(&dev->dev, dev->dev.of_node);
186
187	if (of_device_add(dev) != 0) {
188		platform_device_put(dev);
189		goto err_clear_flag;
190	}
191
192	return dev;
193
194err_clear_flag:
195	of_node_clear_flag(np, OF_POPULATED);
196	return NULL;
197}
198
199/**
200 * of_platform_device_create - Alloc, initialize and register an of_device
201 * @np: pointer to node to create device for
202 * @bus_id: name to assign device
203 * @parent: Linux device model parent device.
204 *
205 * Returns pointer to created platform device, or NULL if a device was not
206 * registered.  Unavailable devices will not get registered.
207 */
208struct platform_device *of_platform_device_create(struct device_node *np,
209					    const char *bus_id,
210					    struct device *parent)
211{
212	return of_platform_device_create_pdata(np, bus_id, NULL, parent);
213}
214EXPORT_SYMBOL(of_platform_device_create);
215
216#ifdef CONFIG_ARM_AMBA
217static struct amba_device *of_amba_device_create(struct device_node *node,
218						 const char *bus_id,
219						 void *platform_data,
220						 struct device *parent)
221{
222	struct amba_device *dev;
223	const void *prop;
224	int i, ret;
225
226	pr_debug("Creating amba device %pOF\n", node);
227
228	if (!of_device_is_available(node) ||
229	    of_node_test_and_set_flag(node, OF_POPULATED))
230		return NULL;
231
232	dev = amba_device_alloc(NULL, 0, 0);
233	if (!dev)
234		goto err_clear_flag;
235
 
 
 
 
236	/* setup generic device info */
237	dev->dev.of_node = of_node_get(node);
238	dev->dev.fwnode = &node->fwnode;
239	dev->dev.parent = parent ? : &platform_bus;
240	dev->dev.platform_data = platform_data;
241	if (bus_id)
242		dev_set_name(&dev->dev, "%s", bus_id);
243	else
244		of_device_make_bus_id(&dev->dev);
245
246	/* Allow the HW Peripheral ID to be overridden */
247	prop = of_get_property(node, "arm,primecell-periphid", NULL);
248	if (prop)
249		dev->periphid = of_read_ulong(prop, 1);
250
251	/* Decode the IRQs and address ranges */
252	for (i = 0; i < AMBA_NR_IRQS; i++)
253		dev->irq[i] = irq_of_parse_and_map(node, i);
254
255	ret = of_address_to_resource(node, 0, &dev->res);
256	if (ret) {
257		pr_err("amba: of_address_to_resource() failed (%d) for %pOF\n",
258		       ret, node);
259		goto err_free;
260	}
261
262	ret = amba_device_add(dev, &iomem_resource);
263	if (ret) {
264		pr_err("amba_device_add() failed (%d) for %pOF\n",
265		       ret, node);
266		goto err_free;
267	}
268
269	return dev;
270
271err_free:
272	amba_device_put(dev);
273err_clear_flag:
274	of_node_clear_flag(node, OF_POPULATED);
275	return NULL;
276}
277#else /* CONFIG_ARM_AMBA */
278static struct amba_device *of_amba_device_create(struct device_node *node,
279						 const char *bus_id,
280						 void *platform_data,
281						 struct device *parent)
282{
283	return NULL;
284}
285#endif /* CONFIG_ARM_AMBA */
286
287/**
288 * of_devname_lookup() - Given a device node, lookup the preferred Linux name
289 */
290static const struct of_dev_auxdata *of_dev_lookup(const struct of_dev_auxdata *lookup,
291				 struct device_node *np)
292{
293	const struct of_dev_auxdata *auxdata;
294	struct resource res;
295	int compatible = 0;
296
297	if (!lookup)
298		return NULL;
299
300	auxdata = lookup;
301	for (; auxdata->compatible; auxdata++) {
302		if (!of_device_is_compatible(np, auxdata->compatible))
303			continue;
304		compatible++;
305		if (!of_address_to_resource(np, 0, &res))
306			if (res.start != auxdata->phys_addr)
307				continue;
308		pr_debug("%pOF: devname=%s\n", np, auxdata->name);
309		return auxdata;
310	}
311
312	if (!compatible)
313		return NULL;
314
315	/* Try compatible match if no phys_addr and name are specified */
316	auxdata = lookup;
317	for (; auxdata->compatible; auxdata++) {
318		if (!of_device_is_compatible(np, auxdata->compatible))
319			continue;
320		if (!auxdata->phys_addr && !auxdata->name) {
321			pr_debug("%pOF: compatible match\n", np);
322			return auxdata;
323		}
324	}
325
326	return NULL;
327}
328
329/**
330 * of_platform_bus_create() - Create a device for a node and its children.
331 * @bus: device node of the bus to instantiate
332 * @matches: match table for bus nodes
333 * @lookup: auxdata table for matching id and platform_data with device nodes
334 * @parent: parent for new device, or NULL for top level.
335 * @strict: require compatible property
336 *
337 * Creates a platform_device for the provided device_node, and optionally
338 * recursively create devices for all the child nodes.
339 */
340static int of_platform_bus_create(struct device_node *bus,
341				  const struct of_device_id *matches,
342				  const struct of_dev_auxdata *lookup,
343				  struct device *parent, bool strict)
344{
345	const struct of_dev_auxdata *auxdata;
346	struct device_node *child;
347	struct platform_device *dev;
348	const char *bus_id = NULL;
349	void *platform_data = NULL;
350	int rc = 0;
351
352	/* Make sure it has a compatible property */
353	if (strict && (!of_get_property(bus, "compatible", NULL))) {
354		pr_debug("%s() - skipping %pOF, no compatible prop\n",
355			 __func__, bus);
356		return 0;
357	}
358
 
 
 
 
 
 
359	if (of_node_check_flag(bus, OF_POPULATED_BUS)) {
360		pr_debug("%s() - skipping %pOF, already populated\n",
361			__func__, bus);
362		return 0;
363	}
364
365	auxdata = of_dev_lookup(lookup, bus);
366	if (auxdata) {
367		bus_id = auxdata->name;
368		platform_data = auxdata->platform_data;
369	}
370
371	if (of_device_is_compatible(bus, "arm,primecell")) {
372		/*
373		 * Don't return an error here to keep compatibility with older
374		 * device tree files.
375		 */
376		of_amba_device_create(bus, bus_id, platform_data, parent);
377		return 0;
378	}
379
380	dev = of_platform_device_create_pdata(bus, bus_id, platform_data, parent);
381	if (!dev || !of_match_node(matches, bus))
382		return 0;
383
384	for_each_child_of_node(bus, child) {
385		pr_debug("   create child: %pOF\n", child);
386		rc = of_platform_bus_create(child, matches, lookup, &dev->dev, strict);
387		if (rc) {
388			of_node_put(child);
389			break;
390		}
391	}
392	of_node_set_flag(bus, OF_POPULATED_BUS);
393	return rc;
394}
395
396/**
397 * of_platform_bus_probe() - Probe the device-tree for platform buses
398 * @root: parent of the first level to probe or NULL for the root of the tree
399 * @matches: match table for bus nodes
400 * @parent: parent to hook devices from, NULL for toplevel
401 *
402 * Note that children of the provided root are not instantiated as devices
403 * unless the specified root itself matches the bus list and is not NULL.
404 */
405int of_platform_bus_probe(struct device_node *root,
406			  const struct of_device_id *matches,
407			  struct device *parent)
408{
409	struct device_node *child;
410	int rc = 0;
411
412	root = root ? of_node_get(root) : of_find_node_by_path("/");
413	if (!root)
414		return -EINVAL;
415
416	pr_debug("%s()\n", __func__);
417	pr_debug(" starting at: %pOF\n", root);
418
419	/* Do a self check of bus type, if there's a match, create children */
420	if (of_match_node(matches, root)) {
421		rc = of_platform_bus_create(root, matches, NULL, parent, false);
422	} else for_each_child_of_node(root, child) {
423		if (!of_match_node(matches, child))
424			continue;
425		rc = of_platform_bus_create(child, matches, NULL, parent, false);
426		if (rc) {
427			of_node_put(child);
428			break;
429		}
430	}
431
432	of_node_put(root);
433	return rc;
434}
435EXPORT_SYMBOL(of_platform_bus_probe);
436
437/**
438 * of_platform_populate() - Populate platform_devices from device tree data
439 * @root: parent of the first level to probe or NULL for the root of the tree
440 * @matches: match table, NULL to use the default
441 * @lookup: auxdata table for matching id and platform_data with device nodes
442 * @parent: parent to hook devices from, NULL for toplevel
443 *
444 * Similar to of_platform_bus_probe(), this function walks the device tree
445 * and creates devices from nodes.  It differs in that it follows the modern
446 * convention of requiring all device nodes to have a 'compatible' property,
447 * and it is suitable for creating devices which are children of the root
448 * node (of_platform_bus_probe will only create children of the root which
449 * are selected by the @matches argument).
450 *
451 * New board support should be using this function instead of
452 * of_platform_bus_probe().
453 *
454 * Returns 0 on success, < 0 on failure.
455 */
456int of_platform_populate(struct device_node *root,
457			const struct of_device_id *matches,
458			const struct of_dev_auxdata *lookup,
459			struct device *parent)
460{
461	struct device_node *child;
462	int rc = 0;
463
464	root = root ? of_node_get(root) : of_find_node_by_path("/");
465	if (!root)
466		return -EINVAL;
467
468	pr_debug("%s()\n", __func__);
469	pr_debug(" starting at: %pOF\n", root);
470
 
471	for_each_child_of_node(root, child) {
472		rc = of_platform_bus_create(child, matches, lookup, parent, true);
473		if (rc) {
474			of_node_put(child);
475			break;
476		}
477	}
 
 
478	of_node_set_flag(root, OF_POPULATED_BUS);
479
480	of_node_put(root);
481	return rc;
482}
483EXPORT_SYMBOL_GPL(of_platform_populate);
484
485int of_platform_default_populate(struct device_node *root,
486				 const struct of_dev_auxdata *lookup,
487				 struct device *parent)
488{
489	return of_platform_populate(root, of_default_bus_match_table, lookup,
490				    parent);
491}
492EXPORT_SYMBOL_GPL(of_platform_default_populate);
493
494#ifndef CONFIG_PPC
495static const struct of_device_id reserved_mem_matches[] = {
496	{ .compatible = "qcom,rmtfs-mem" },
 
497	{ .compatible = "ramoops" },
 
498	{}
499};
500
501static int __init of_platform_default_populate_init(void)
502{
503	struct device_node *node;
504
 
 
505	if (!of_have_populated_dt())
506		return -ENODEV;
507
508	/*
509	 * Handle certain compatibles explicitly, since we don't want to create
510	 * platform_devices for every node in /reserved-memory with a
511	 * "compatible",
512	 */
513	for_each_matching_node(node, reserved_mem_matches)
514		of_platform_device_create(node, NULL, NULL);
515
516	node = of_find_node_by_path("/firmware");
517	if (node) {
518		of_platform_populate(node, NULL, NULL, NULL);
519		of_node_put(node);
520	}
521
522	/* Populate everything else. */
523	of_platform_default_populate(NULL, NULL, NULL);
524
525	return 0;
526}
527arch_initcall_sync(of_platform_default_populate_init);
 
 
 
 
 
 
 
528#endif
529
530int of_platform_device_destroy(struct device *dev, void *data)
531{
532	/* Do not touch devices not populated from the device tree */
533	if (!dev->of_node || !of_node_check_flag(dev->of_node, OF_POPULATED))
534		return 0;
535
536	/* Recurse for any nodes that were treated as busses */
537	if (of_node_check_flag(dev->of_node, OF_POPULATED_BUS))
538		device_for_each_child(dev, NULL, of_platform_device_destroy);
539
 
 
 
540	if (dev->bus == &platform_bus_type)
541		platform_device_unregister(to_platform_device(dev));
542#ifdef CONFIG_ARM_AMBA
543	else if (dev->bus == &amba_bustype)
544		amba_device_unregister(to_amba_device(dev));
545#endif
546
547	of_node_clear_flag(dev->of_node, OF_POPULATED);
548	of_node_clear_flag(dev->of_node, OF_POPULATED_BUS);
549	return 0;
550}
551EXPORT_SYMBOL_GPL(of_platform_device_destroy);
552
553/**
554 * of_platform_depopulate() - Remove devices populated from device tree
555 * @parent: device which children will be removed
556 *
557 * Complementary to of_platform_populate(), this function removes children
558 * of the given device (and, recurrently, their children) that have been
559 * created from their respective device tree nodes (and only those,
560 * leaving others - eg. manually created - unharmed).
561 */
562void of_platform_depopulate(struct device *parent)
563{
564	if (parent->of_node && of_node_check_flag(parent->of_node, OF_POPULATED_BUS)) {
565		device_for_each_child(parent, NULL, of_platform_device_destroy);
566		of_node_clear_flag(parent->of_node, OF_POPULATED_BUS);
567	}
568}
569EXPORT_SYMBOL_GPL(of_platform_depopulate);
570
571static void devm_of_platform_populate_release(struct device *dev, void *res)
572{
573	of_platform_depopulate(*(struct device **)res);
574}
575
576/**
577 * devm_of_platform_populate() - Populate platform_devices from device tree data
578 * @dev: device that requested to populate from device tree data
579 *
580 * Similar to of_platform_populate(), but will automatically call
581 * of_platform_depopulate() when the device is unbound from the bus.
582 *
583 * Returns 0 on success, < 0 on failure.
584 */
585int devm_of_platform_populate(struct device *dev)
586{
587	struct device **ptr;
588	int ret;
589
590	if (!dev)
591		return -EINVAL;
592
593	ptr = devres_alloc(devm_of_platform_populate_release,
594			   sizeof(*ptr), GFP_KERNEL);
595	if (!ptr)
596		return -ENOMEM;
597
598	ret = of_platform_populate(dev->of_node, NULL, NULL, dev);
599	if (ret) {
600		devres_free(ptr);
601	} else {
602		*ptr = dev;
603		devres_add(dev, ptr);
604	}
605
606	return ret;
607}
608EXPORT_SYMBOL_GPL(devm_of_platform_populate);
609
610static int devm_of_platform_match(struct device *dev, void *res, void *data)
611{
612	struct device **ptr = res;
613
614	if (!ptr) {
615		WARN_ON(!ptr);
616		return 0;
617	}
618
619	return *ptr == data;
620}
621
622/**
623 * devm_of_platform_depopulate() - Remove devices populated from device tree
624 * @dev: device that requested to depopulate from device tree data
625 *
626 * Complementary to devm_of_platform_populate(), this function removes children
627 * of the given device (and, recurrently, their children) that have been
628 * created from their respective device tree nodes (and only those,
629 * leaving others - eg. manually created - unharmed).
630 */
631void devm_of_platform_depopulate(struct device *dev)
632{
633	int ret;
634
635	ret = devres_release(dev, devm_of_platform_populate_release,
636			     devm_of_platform_match, dev);
637
638	WARN_ON(ret);
639}
640EXPORT_SYMBOL_GPL(devm_of_platform_depopulate);
641
642#ifdef CONFIG_OF_DYNAMIC
643static int of_platform_notify(struct notifier_block *nb,
644				unsigned long action, void *arg)
645{
646	struct of_reconfig_data *rd = arg;
647	struct platform_device *pdev_parent, *pdev;
648	bool children_left;
649
650	switch (of_reconfig_get_state_change(action, rd)) {
651	case OF_RECONFIG_CHANGE_ADD:
652		/* verify that the parent is a bus */
653		if (!of_node_check_flag(rd->dn->parent, OF_POPULATED_BUS))
654			return NOTIFY_OK;	/* not for us */
655
656		/* already populated? (driver using of_populate manually) */
657		if (of_node_check_flag(rd->dn, OF_POPULATED))
658			return NOTIFY_OK;
659
660		/* pdev_parent may be NULL when no bus platform device */
661		pdev_parent = of_find_device_by_node(rd->dn->parent);
662		pdev = of_platform_device_create(rd->dn, NULL,
663				pdev_parent ? &pdev_parent->dev : NULL);
664		of_dev_put(pdev_parent);
665
666		if (pdev == NULL) {
667			pr_err("%s: failed to create for '%pOF'\n",
668					__func__, rd->dn);
669			/* of_platform_device_create tosses the error code */
670			return notifier_from_errno(-EINVAL);
671		}
672		break;
673
674	case OF_RECONFIG_CHANGE_REMOVE:
675
676		/* already depopulated? */
677		if (!of_node_check_flag(rd->dn, OF_POPULATED))
678			return NOTIFY_OK;
679
680		/* find our device by node */
681		pdev = of_find_device_by_node(rd->dn);
682		if (pdev == NULL)
683			return NOTIFY_OK;	/* no? not meant for us */
684
685		/* unregister takes one ref away */
686		of_platform_device_destroy(&pdev->dev, &children_left);
687
688		/* and put the reference of the find */
689		of_dev_put(pdev);
690		break;
691	}
692
693	return NOTIFY_OK;
694}
695
696static struct notifier_block platform_of_notifier = {
697	.notifier_call = of_platform_notify,
698};
699
700void of_platform_register_reconfig_notifier(void)
701{
702	WARN_ON(of_reconfig_notifier_register(&platform_of_notifier));
703}
704#endif /* CONFIG_OF_DYNAMIC */
705
706#endif /* CONFIG_OF_ADDRESS */