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v6.8
  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 */
v3.1
 
  1/*
  2 *    Copyright (C) 2006 Benjamin Herrenschmidt, IBM Corp.
  3 *			 <benh@kernel.crashing.org>
  4 *    and		 Arnd Bergmann, IBM Corp.
  5 *    Merged from powerpc/kernel/of_platform.c and
  6 *    sparc{,64}/kernel/of_device.c by Stephen Rothwell
  7 *
  8 *  This program is free software; you can redistribute it and/or
  9 *  modify it under the terms of the GNU General Public License
 10 *  as published by the Free Software Foundation; either version
 11 *  2 of the License, or (at your option) any later version.
 12 *
 13 */
 
 
 
 14#include <linux/errno.h>
 15#include <linux/module.h>
 16#include <linux/amba/bus.h>
 17#include <linux/device.h>
 18#include <linux/dma-mapping.h>
 19#include <linux/slab.h>
 20#include <linux/of_address.h>
 21#include <linux/of_device.h>
 22#include <linux/of_irq.h>
 23#include <linux/of_platform.h>
 24#include <linux/platform_device.h>
 
 
 
 25
 26const struct of_device_id of_default_bus_match_table[] = {
 27	{ .compatible = "simple-bus", },
 
 
 28#ifdef CONFIG_ARM_AMBA
 29	{ .compatible = "arm,amba-bus", },
 30#endif /* CONFIG_ARM_AMBA */
 31	{} /* Empty terminated list */
 32};
 33
 34static int of_dev_node_match(struct device *dev, void *data)
 35{
 36	return dev->of_node == data;
 37}
 38
 39/**
 40 * of_find_device_by_node - Find the platform_device associated with a node
 41 * @np: Pointer to device tree node
 42 *
 43 * Returns platform_device pointer, or NULL if not found
 
 
 
 44 */
 45struct platform_device *of_find_device_by_node(struct device_node *np)
 46{
 47	struct device *dev;
 48
 49	dev = bus_find_device(&platform_bus_type, NULL, np, of_dev_node_match);
 50	return dev ? to_platform_device(dev) : NULL;
 51}
 52EXPORT_SYMBOL(of_find_device_by_node);
 53
 54#if defined(CONFIG_PPC_DCR)
 55#include <asm/dcr.h>
 56#endif
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 57
 58#if !defined(CONFIG_SPARC)
 59/*
 60 * The following routines scan a subtree and registers a device for
 61 * each applicable node.
 62 *
 63 * Note: sparc doesn't use these routines because it has a different
 64 * mechanism for creating devices from device tree nodes.
 65 */
 66
 67/**
 68 * of_device_make_bus_id - Use the device node data to assign a unique name
 69 * @dev: pointer to device structure that is linked to a device tree node
 70 *
 71 * This routine will first try using either the dcr-reg or the reg property
 72 * value to derive a unique name.  As a last resort it will use the node
 73 * name followed by a unique number.
 74 */
 75void of_device_make_bus_id(struct device *dev)
 76{
 77	static atomic_t bus_no_reg_magic;
 78	struct device_node *node = dev->of_node;
 79	const u32 *reg;
 80	u64 addr;
 81	int magic;
 82
 83#ifdef CONFIG_PPC_DCR
 84	/*
 85	 * If it's a DCR based device, use 'd' for native DCRs
 86	 * and 'D' for MMIO DCRs.
 87	 */
 88	reg = of_get_property(node, "dcr-reg", NULL);
 89	if (reg) {
 90#ifdef CONFIG_PPC_DCR_NATIVE
 91		dev_set_name(dev, "d%x.%s", *reg, node->name);
 92#else /* CONFIG_PPC_DCR_NATIVE */
 93		u64 addr = of_translate_dcr_address(node, *reg, NULL);
 94		if (addr != OF_BAD_ADDR) {
 95			dev_set_name(dev, "D%llx.%s",
 96				     (unsigned long long)addr, node->name);
 97			return;
 98		}
 99#endif /* !CONFIG_PPC_DCR_NATIVE */
100	}
101#endif /* CONFIG_PPC_DCR */
102
103	/*
104	 * For MMIO, get the physical address
105	 */
106	reg = of_get_property(node, "reg", NULL);
107	if (reg) {
108		addr = of_translate_address(node, reg);
109		if (addr != OF_BAD_ADDR) {
110			dev_set_name(dev, "%llx.%s",
111				     (unsigned long long)addr, node->name);
112			return;
113		}
114	}
115
116	/*
117	 * No BusID, use the node name and add a globally incremented
118	 * counter (and pray...)
119	 */
120	magic = atomic_add_return(1, &bus_no_reg_magic);
121	dev_set_name(dev, "%s.%d", node->name, magic - 1);
122}
123
124/**
125 * of_device_alloc - Allocate and initialize an of_device
126 * @np: device node to assign to device
127 * @bus_id: Name to assign to the device.  May be null to use default name.
128 * @parent: Parent device.
129 */
130struct platform_device *of_device_alloc(struct device_node *np,
131				  const char *bus_id,
132				  struct device *parent)
133{
134	struct platform_device *dev;
135	int rc, i, num_reg = 0, num_irq;
136	struct resource *res, temp_res;
137
138	dev = platform_device_alloc("", -1);
139	if (!dev)
140		return NULL;
141
142	/* count the io and irq resources */
143	while (of_address_to_resource(np, num_reg, &temp_res) == 0)
144		num_reg++;
145	num_irq = of_irq_count(np);
146
147	/* Populate the resource table */
148	if (num_irq || num_reg) {
149		res = kzalloc(sizeof(*res) * (num_irq + num_reg), GFP_KERNEL);
150		if (!res) {
151			platform_device_put(dev);
152			return NULL;
153		}
154
155		dev->num_resources = num_reg + num_irq;
156		dev->resource = res;
157		for (i = 0; i < num_reg; i++, res++) {
158			rc = of_address_to_resource(np, i, res);
159			WARN_ON(rc);
160		}
161		WARN_ON(of_irq_to_resource_table(np, res, num_irq) != num_irq);
162	}
163
164	dev->dev.of_node = of_node_get(np);
165#if defined(CONFIG_MICROBLAZE)
166	dev->dev.dma_mask = &dev->archdata.dma_mask;
167#endif
168	dev->dev.parent = parent;
169
170	if (bus_id)
171		dev_set_name(&dev->dev, "%s", bus_id);
172	else
173		of_device_make_bus_id(&dev->dev);
174
175	return dev;
176}
177EXPORT_SYMBOL(of_device_alloc);
178
179/**
180 * of_platform_device_create_pdata - Alloc, initialize and register an of_device
181 * @np: pointer to node to create device for
182 * @bus_id: name to assign device
183 * @platform_data: pointer to populate platform_data pointer with
184 * @parent: Linux device model parent device.
185 *
186 * Returns pointer to created platform device, or NULL if a device was not
187 * registered.  Unavailable devices will not get registered.
188 */
189struct platform_device *of_platform_device_create_pdata(
190					struct device_node *np,
191					const char *bus_id,
192					void *platform_data,
193					struct device *parent)
194{
195	struct platform_device *dev;
196
197	if (!of_device_is_available(np))
 
198		return NULL;
199
200	dev = of_device_alloc(np, bus_id, parent);
201	if (!dev)
202		return NULL;
203
204#if defined(CONFIG_MICROBLAZE)
205	dev->archdata.dma_mask = 0xffffffffUL;
206#endif
207	dev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
 
 
208	dev->dev.bus = &platform_bus_type;
209	dev->dev.platform_data = platform_data;
210
211	/* We do not fill the DMA ops for platform devices by default.
212	 * This is currently the responsibility of the platform code
213	 * to do such, possibly using a device notifier
214	 */
215
216	if (of_device_add(dev) != 0) {
217		platform_device_put(dev);
218		return NULL;
219	}
220
221	return dev;
 
 
 
 
222}
223
224/**
225 * of_platform_device_create - Alloc, initialize and register an of_device
226 * @np: pointer to node to create device for
227 * @bus_id: name to assign device
228 * @parent: Linux device model parent device.
229 *
230 * Returns pointer to created platform device, or NULL if a device was not
231 * registered.  Unavailable devices will not get registered.
232 */
233struct platform_device *of_platform_device_create(struct device_node *np,
234					    const char *bus_id,
235					    struct device *parent)
236{
237	return of_platform_device_create_pdata(np, bus_id, NULL, parent);
238}
239EXPORT_SYMBOL(of_platform_device_create);
240
241#ifdef CONFIG_ARM_AMBA
242static struct amba_device *of_amba_device_create(struct device_node *node,
243						 const char *bus_id,
244						 void *platform_data,
245						 struct device *parent)
246{
247	struct amba_device *dev;
248	const void *prop;
249	int i, ret;
250
251	pr_debug("Creating amba device %s\n", node->full_name);
252
253	if (!of_device_is_available(node))
 
254		return NULL;
255
256	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
257	if (!dev)
258		return NULL;
 
 
 
 
259
260	/* setup generic device info */
261	dev->dev.coherent_dma_mask = ~0;
262	dev->dev.of_node = of_node_get(node);
263	dev->dev.parent = parent;
264	dev->dev.platform_data = platform_data;
265	if (bus_id)
266		dev_set_name(&dev->dev, "%s", bus_id);
267	else
268		of_device_make_bus_id(&dev->dev);
269
270	/* setup amba-specific device info */
271	dev->dma_mask = ~0;
272
273	/* Allow the HW Peripheral ID to be overridden */
274	prop = of_get_property(node, "arm,primecell-periphid", NULL);
275	if (prop)
276		dev->periphid = of_read_ulong(prop, 1);
277
278	/* Decode the IRQs and address ranges */
279	for (i = 0; i < AMBA_NR_IRQS; i++)
280		dev->irq[i] = irq_of_parse_and_map(node, i);
281
282	ret = of_address_to_resource(node, 0, &dev->res);
283	if (ret)
 
 
284		goto err_free;
 
285
286	ret = amba_device_register(dev, &iomem_resource);
287	if (ret)
 
 
288		goto err_free;
 
289
290	return dev;
291
292err_free:
293	kfree(dev);
 
 
294	return NULL;
295}
296#else /* CONFIG_ARM_AMBA */
297static struct amba_device *of_amba_device_create(struct device_node *node,
298						 const char *bus_id,
299						 void *platform_data,
300						 struct device *parent)
301{
302	return NULL;
303}
304#endif /* CONFIG_ARM_AMBA */
305
306/**
307 * of_devname_lookup() - Given a device node, lookup the preferred Linux name
308 */
309static const struct of_dev_auxdata *of_dev_lookup(const struct of_dev_auxdata *lookup,
310				 struct device_node *np)
311{
 
312	struct resource res;
313	if (lookup) {
314		for(; lookup->name != NULL; lookup++) {
315			if (!of_device_is_compatible(np, lookup->compatible))
 
 
 
 
 
 
 
 
 
316				continue;
317			if (of_address_to_resource(np, 0, &res))
318				continue;
319			if (res.start != lookup->phys_addr)
320				continue;
321			pr_debug("%s: devname=%s\n", np->full_name, lookup->name);
322			return lookup;
 
 
 
 
 
 
 
 
 
323		}
324	}
 
325	return NULL;
326}
327
328/**
329 * of_platform_bus_create() - Create a device for a node and its children.
330 * @bus: device node of the bus to instantiate
331 * @matches: match table for bus nodes
332 * disallow recursive creation of child buses
333 * @parent: parent for new device, or NULL for top level.
 
334 *
335 * Creates a platform_device for the provided device_node, and optionally
336 * recursively create devices for all the child nodes.
337 */
338static int of_platform_bus_create(struct device_node *bus,
339				  const struct of_device_id *matches,
340				  const struct of_dev_auxdata *lookup,
341				  struct device *parent, bool strict)
342{
343	const struct of_dev_auxdata *auxdata;
344	struct device_node *child;
345	struct platform_device *dev;
346	const char *bus_id = NULL;
347	void *platform_data = NULL;
348	int rc = 0;
349
350	/* Make sure it has a compatible property */
351	if (strict && (!of_get_property(bus, "compatible", NULL))) {
352		pr_debug("%s() - skipping %s, no compatible prop\n",
353			 __func__, bus->full_name);
 
 
 
 
 
 
 
 
 
 
 
 
354		return 0;
355	}
356
357	auxdata = of_dev_lookup(lookup, bus);
358	if (auxdata) {
359		bus_id = auxdata->name;
360		platform_data = auxdata->platform_data;
361	}
362
363	if (of_device_is_compatible(bus, "arm,primecell")) {
 
 
 
 
364		of_amba_device_create(bus, bus_id, platform_data, parent);
365		return 0;
366	}
367
368	dev = of_platform_device_create_pdata(bus, bus_id, platform_data, parent);
369	if (!dev || !of_match_node(matches, bus))
370		return 0;
371
372	for_each_child_of_node(bus, child) {
373		pr_debug("   create child: %s\n", child->full_name);
374		rc = of_platform_bus_create(child, matches, lookup, &dev->dev, strict);
375		if (rc) {
376			of_node_put(child);
377			break;
378		}
379	}
 
380	return rc;
381}
382
383/**
384 * of_platform_bus_probe() - Probe the device-tree for platform buses
385 * @root: parent of the first level to probe or NULL for the root of the tree
386 * @matches: match table for bus nodes
387 * @parent: parent to hook devices from, NULL for toplevel
388 *
389 * Note that children of the provided root are not instantiated as devices
390 * unless the specified root itself matches the bus list and is not NULL.
391 */
392int of_platform_bus_probe(struct device_node *root,
393			  const struct of_device_id *matches,
394			  struct device *parent)
395{
396	struct device_node *child;
397	int rc = 0;
398
399	root = root ? of_node_get(root) : of_find_node_by_path("/");
400	if (!root)
401		return -EINVAL;
402
403	pr_debug("of_platform_bus_probe()\n");
404	pr_debug(" starting at: %s\n", root->full_name);
405
406	/* Do a self check of bus type, if there's a match, create children */
407	if (of_match_node(matches, root)) {
408		rc = of_platform_bus_create(root, matches, NULL, parent, false);
409	} else for_each_child_of_node(root, child) {
410		if (!of_match_node(matches, child))
411			continue;
412		rc = of_platform_bus_create(child, matches, NULL, parent, false);
413		if (rc)
 
414			break;
 
415	}
416
417	of_node_put(root);
418	return rc;
419}
420EXPORT_SYMBOL(of_platform_bus_probe);
421
422/**
423 * of_platform_populate() - Populate platform_devices from device tree data
424 * @root: parent of the first level to probe or NULL for the root of the tree
425 * @matches: match table, NULL to use the default
 
426 * @parent: parent to hook devices from, NULL for toplevel
427 *
428 * Similar to of_platform_bus_probe(), this function walks the device tree
429 * and creates devices from nodes.  It differs in that it follows the modern
430 * convention of requiring all device nodes to have a 'compatible' property,
431 * and it is suitable for creating devices which are children of the root
432 * node (of_platform_bus_probe will only create children of the root which
433 * are selected by the @matches argument).
434 *
435 * New board support should be using this function instead of
436 * of_platform_bus_probe().
437 *
438 * Returns 0 on success, < 0 on failure.
439 */
440int of_platform_populate(struct device_node *root,
441			const struct of_device_id *matches,
442			const struct of_dev_auxdata *lookup,
443			struct device *parent)
444{
445	struct device_node *child;
446	int rc = 0;
447
448	root = root ? of_node_get(root) : of_find_node_by_path("/");
449	if (!root)
450		return -EINVAL;
451
 
 
 
 
452	for_each_child_of_node(root, child) {
453		rc = of_platform_bus_create(child, matches, lookup, parent, true);
454		if (rc)
 
455			break;
 
456	}
 
 
 
457
458	of_node_put(root);
459	return rc;
460}
461#endif /* !CONFIG_SPARC */