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  1/*
  2 *    Copyright (C) 2006 Benjamin Herrenschmidt, IBM Corp.
  3 *			 <benh@kernel.crashing.org>
  4 *    and		 Arnd Bergmann, IBM Corp.
  5 *    Merged from powerpc/kernel/of_platform.c and
  6 *    sparc{,64}/kernel/of_device.c by Stephen Rothwell
  7 *
  8 *  This program is free software; you can redistribute it and/or
  9 *  modify it under the terms of the GNU General Public License
 10 *  as published by the Free Software Foundation; either version
 11 *  2 of the License, or (at your option) any later version.
 12 *
 13 */
 14#include <linux/errno.h>
 15#include <linux/module.h>
 16#include <linux/amba/bus.h>
 17#include <linux/device.h>
 18#include <linux/dma-mapping.h>
 19#include <linux/slab.h>
 20#include <linux/of_address.h>
 21#include <linux/of_device.h>
 22#include <linux/of_irq.h>
 23#include <linux/of_platform.h>
 24#include <linux/platform_device.h>
 25
 26const struct of_device_id of_default_bus_match_table[] = {
 27	{ .compatible = "simple-bus", },
 
 28#ifdef CONFIG_ARM_AMBA
 29	{ .compatible = "arm,amba-bus", },
 30#endif /* CONFIG_ARM_AMBA */
 31	{} /* Empty terminated list */
 32};
 
 33
 34static int of_dev_node_match(struct device *dev, void *data)
 35{
 36	return dev->of_node == data;
 37}
 38
 39/**
 40 * of_find_device_by_node - Find the platform_device associated with a node
 41 * @np: Pointer to device tree node
 42 *
 43 * Returns platform_device pointer, or NULL if not found
 44 */
 45struct platform_device *of_find_device_by_node(struct device_node *np)
 46{
 47	struct device *dev;
 48
 49	dev = bus_find_device(&platform_bus_type, NULL, np, of_dev_node_match);
 50	return dev ? to_platform_device(dev) : NULL;
 51}
 52EXPORT_SYMBOL(of_find_device_by_node);
 53
 54#if defined(CONFIG_PPC_DCR)
 55#include <asm/dcr.h>
 56#endif
 57
 58#ifdef CONFIG_OF_ADDRESS
 59/*
 60 * The following routines scan a subtree and registers a device for
 61 * each applicable node.
 62 *
 63 * Note: sparc doesn't use these routines because it has a different
 64 * mechanism for creating devices from device tree nodes.
 65 */
 66
 67/**
 68 * of_device_make_bus_id - Use the device node data to assign a unique name
 69 * @dev: pointer to device structure that is linked to a device tree node
 70 *
 71 * This routine will first try using either the dcr-reg or the reg property
 72 * value to derive a unique name.  As a last resort it will use the node
 73 * name followed by a unique number.
 74 */
 75void of_device_make_bus_id(struct device *dev)
 76{
 77	static atomic_t bus_no_reg_magic;
 78	struct device_node *node = dev->of_node;
 79	const __be32 *reg;
 80	u64 addr;
 81	const __be32 *addrp;
 82	int magic;
 83
 84#ifdef CONFIG_PPC_DCR
 85	/*
 86	 * If it's a DCR based device, use 'd' for native DCRs
 87	 * and 'D' for MMIO DCRs.
 88	 */
 89	reg = of_get_property(node, "dcr-reg", NULL);
 90	if (reg) {
 91#ifdef CONFIG_PPC_DCR_NATIVE
 92		dev_set_name(dev, "d%x.%s", *reg, node->name);
 93#else /* CONFIG_PPC_DCR_NATIVE */
 94		u64 addr = of_translate_dcr_address(node, *reg, NULL);
 95		if (addr != OF_BAD_ADDR) {
 96			dev_set_name(dev, "D%llx.%s",
 97				     (unsigned long long)addr, node->name);
 98			return;
 99		}
100#endif /* !CONFIG_PPC_DCR_NATIVE */
101	}
102#endif /* CONFIG_PPC_DCR */
103
104	/*
105	 * For MMIO, get the physical address
106	 */
107	reg = of_get_property(node, "reg", NULL);
108	if (reg) {
109		if (of_can_translate_address(node)) {
110			addr = of_translate_address(node, reg);
111		} else {
112			addrp = of_get_address(node, 0, NULL, NULL);
113			if (addrp)
114				addr = of_read_number(addrp, 1);
115			else
116				addr = OF_BAD_ADDR;
117		}
118		if (addr != OF_BAD_ADDR) {
119			dev_set_name(dev, "%llx.%s",
120				     (unsigned long long)addr, node->name);
121			return;
122		}
123	}
124
125	/*
126	 * No BusID, use the node name and add a globally incremented
127	 * counter (and pray...)
128	 */
129	magic = atomic_add_return(1, &bus_no_reg_magic);
130	dev_set_name(dev, "%s.%d", node->name, magic - 1);
131}
132
133/**
134 * of_device_alloc - Allocate and initialize an of_device
135 * @np: device node to assign to device
136 * @bus_id: Name to assign to the device.  May be null to use default name.
137 * @parent: Parent device.
138 */
139struct platform_device *of_device_alloc(struct device_node *np,
140				  const char *bus_id,
141				  struct device *parent)
142{
143	struct platform_device *dev;
144	int rc, i, num_reg = 0, num_irq;
145	struct resource *res, temp_res;
146
147	dev = platform_device_alloc("", -1);
148	if (!dev)
149		return NULL;
150
151	/* count the io and irq resources */
152	if (of_can_translate_address(np))
153		while (of_address_to_resource(np, num_reg, &temp_res) == 0)
154			num_reg++;
155	num_irq = of_irq_count(np);
156
157	/* Populate the resource table */
158	if (num_irq || num_reg) {
159		res = kzalloc(sizeof(*res) * (num_irq + num_reg), GFP_KERNEL);
160		if (!res) {
161			platform_device_put(dev);
162			return NULL;
163		}
164
165		dev->num_resources = num_reg + num_irq;
166		dev->resource = res;
167		for (i = 0; i < num_reg; i++, res++) {
168			rc = of_address_to_resource(np, i, res);
169			WARN_ON(rc);
170		}
171		if (of_irq_to_resource_table(np, res, num_irq) != num_irq)
172			pr_debug("not all legacy IRQ resources mapped for %s\n",
173				 np->name);
174	}
175
176	dev->dev.of_node = of_node_get(np);
177#if defined(CONFIG_MICROBLAZE)
178	dev->dev.dma_mask = &dev->archdata.dma_mask;
179#endif
180	dev->dev.parent = parent;
181
182	if (bus_id)
183		dev_set_name(&dev->dev, "%s", bus_id);
184	else
185		of_device_make_bus_id(&dev->dev);
186
187	return dev;
188}
189EXPORT_SYMBOL(of_device_alloc);
190
 
 
 
 
 
191/**
192 * of_platform_device_create_pdata - Alloc, initialize and register an of_device
193 * @np: pointer to node to create device for
194 * @bus_id: name to assign device
195 * @platform_data: pointer to populate platform_data pointer with
196 * @parent: Linux device model parent device.
197 *
198 * Returns pointer to created platform device, or NULL if a device was not
199 * registered.  Unavailable devices will not get registered.
200 */
201static struct platform_device *of_platform_device_create_pdata(
202					struct device_node *np,
203					const char *bus_id,
204					void *platform_data,
205					struct device *parent)
206{
207	struct platform_device *dev;
208
209	if (!of_device_is_available(np))
 
210		return NULL;
211
212	dev = of_device_alloc(np, bus_id, parent);
213	if (!dev)
214		return NULL;
215
216#if defined(CONFIG_MICROBLAZE)
217	dev->archdata.dma_mask = 0xffffffffUL;
218#endif
219	dev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
220	if (!dev->dev.dma_mask)
221		dev->dev.dma_mask = &dev->dev.coherent_dma_mask;
222	dev->dev.bus = &platform_bus_type;
223	dev->dev.platform_data = platform_data;
224
225	/* We do not fill the DMA ops for platform devices by default.
226	 * This is currently the responsibility of the platform code
227	 * to do such, possibly using a device notifier
228	 */
229
230	if (of_device_add(dev) != 0) {
 
231		platform_device_put(dev);
232		return NULL;
233	}
234
235	return dev;
 
 
 
 
236}
237
238/**
239 * of_platform_device_create - Alloc, initialize and register an of_device
240 * @np: pointer to node to create device for
241 * @bus_id: name to assign device
242 * @parent: Linux device model parent device.
243 *
244 * Returns pointer to created platform device, or NULL if a device was not
245 * registered.  Unavailable devices will not get registered.
246 */
247struct platform_device *of_platform_device_create(struct device_node *np,
248					    const char *bus_id,
249					    struct device *parent)
250{
251	return of_platform_device_create_pdata(np, bus_id, NULL, parent);
252}
253EXPORT_SYMBOL(of_platform_device_create);
254
255#ifdef CONFIG_ARM_AMBA
256static struct amba_device *of_amba_device_create(struct device_node *node,
257						 const char *bus_id,
258						 void *platform_data,
259						 struct device *parent)
260{
261	struct amba_device *dev;
262	const void *prop;
263	int i, ret;
264
265	pr_debug("Creating amba device %s\n", node->full_name);
266
267	if (!of_device_is_available(node))
 
268		return NULL;
269
270	dev = amba_device_alloc(NULL, 0, 0);
271	if (!dev) {
272		pr_err("%s(): amba_device_alloc() failed for %s\n",
273		       __func__, node->full_name);
274		return NULL;
275	}
276
277	/* setup generic device info */
278	dev->dev.coherent_dma_mask = ~0;
279	dev->dev.of_node = of_node_get(node);
280	dev->dev.parent = parent;
281	dev->dev.platform_data = platform_data;
282	if (bus_id)
283		dev_set_name(&dev->dev, "%s", bus_id);
284	else
285		of_device_make_bus_id(&dev->dev);
 
286
287	/* Allow the HW Peripheral ID to be overridden */
288	prop = of_get_property(node, "arm,primecell-periphid", NULL);
289	if (prop)
290		dev->periphid = of_read_ulong(prop, 1);
291
292	/* Decode the IRQs and address ranges */
293	for (i = 0; i < AMBA_NR_IRQS; i++)
294		dev->irq[i] = irq_of_parse_and_map(node, i);
295
296	ret = of_address_to_resource(node, 0, &dev->res);
297	if (ret) {
298		pr_err("%s(): of_address_to_resource() failed (%d) for %s\n",
299		       __func__, ret, node->full_name);
300		goto err_free;
301	}
302
303	ret = amba_device_add(dev, &iomem_resource);
304	if (ret) {
305		pr_err("%s(): amba_device_add() failed (%d) for %s\n",
306		       __func__, ret, node->full_name);
307		goto err_free;
308	}
309
310	return dev;
311
312err_free:
313	amba_device_put(dev);
 
 
314	return NULL;
315}
316#else /* CONFIG_ARM_AMBA */
317static struct amba_device *of_amba_device_create(struct device_node *node,
318						 const char *bus_id,
319						 void *platform_data,
320						 struct device *parent)
321{
322	return NULL;
323}
324#endif /* CONFIG_ARM_AMBA */
325
326/**
327 * of_devname_lookup() - Given a device node, lookup the preferred Linux name
328 */
329static const struct of_dev_auxdata *of_dev_lookup(const struct of_dev_auxdata *lookup,
330				 struct device_node *np)
331{
332	struct resource res;
333
334	if (!lookup)
335		return NULL;
336
337	for(; lookup->compatible != NULL; lookup++) {
338		if (!of_device_is_compatible(np, lookup->compatible))
339			continue;
340		if (!of_address_to_resource(np, 0, &res))
341			if (res.start != lookup->phys_addr)
342				continue;
343		pr_debug("%s: devname=%s\n", np->full_name, lookup->name);
344		return lookup;
345	}
346
347	return NULL;
348}
349
350/**
351 * of_platform_bus_create() - Create a device for a node and its children.
352 * @bus: device node of the bus to instantiate
353 * @matches: match table for bus nodes
354 * @lookup: auxdata table for matching id and platform_data with device nodes
355 * @parent: parent for new device, or NULL for top level.
356 * @strict: require compatible property
357 *
358 * Creates a platform_device for the provided device_node, and optionally
359 * recursively create devices for all the child nodes.
360 */
361static int of_platform_bus_create(struct device_node *bus,
362				  const struct of_device_id *matches,
363				  const struct of_dev_auxdata *lookup,
364				  struct device *parent, bool strict)
365{
366	const struct of_dev_auxdata *auxdata;
367	struct device_node *child;
368	struct platform_device *dev;
369	const char *bus_id = NULL;
370	void *platform_data = NULL;
371	int rc = 0;
372
373	/* Make sure it has a compatible property */
374	if (strict && (!of_get_property(bus, "compatible", NULL))) {
375		pr_debug("%s() - skipping %s, no compatible prop\n",
376			 __func__, bus->full_name);
377		return 0;
378	}
379
380	auxdata = of_dev_lookup(lookup, bus);
381	if (auxdata) {
382		bus_id = auxdata->name;
383		platform_data = auxdata->platform_data;
384	}
385
386	if (of_device_is_compatible(bus, "arm,primecell")) {
387		/*
388		 * Don't return an error here to keep compatibility with older
389		 * device tree files.
390		 */
391		of_amba_device_create(bus, bus_id, platform_data, parent);
392		return 0;
393	}
394
395	dev = of_platform_device_create_pdata(bus, bus_id, platform_data, parent);
396	if (!dev || !of_match_node(matches, bus))
397		return 0;
398
399	for_each_child_of_node(bus, child) {
400		pr_debug("   create child: %s\n", child->full_name);
401		rc = of_platform_bus_create(child, matches, lookup, &dev->dev, strict);
402		if (rc) {
403			of_node_put(child);
404			break;
405		}
406	}
 
407	return rc;
408}
409
410/**
411 * of_platform_bus_probe() - Probe the device-tree for platform buses
412 * @root: parent of the first level to probe or NULL for the root of the tree
413 * @matches: match table for bus nodes
414 * @parent: parent to hook devices from, NULL for toplevel
415 *
416 * Note that children of the provided root are not instantiated as devices
417 * unless the specified root itself matches the bus list and is not NULL.
418 */
419int of_platform_bus_probe(struct device_node *root,
420			  const struct of_device_id *matches,
421			  struct device *parent)
422{
423	struct device_node *child;
424	int rc = 0;
425
426	root = root ? of_node_get(root) : of_find_node_by_path("/");
427	if (!root)
428		return -EINVAL;
429
430	pr_debug("of_platform_bus_probe()\n");
431	pr_debug(" starting at: %s\n", root->full_name);
432
433	/* Do a self check of bus type, if there's a match, create children */
434	if (of_match_node(matches, root)) {
435		rc = of_platform_bus_create(root, matches, NULL, parent, false);
436	} else for_each_child_of_node(root, child) {
437		if (!of_match_node(matches, child))
438			continue;
439		rc = of_platform_bus_create(child, matches, NULL, parent, false);
440		if (rc)
 
441			break;
 
442	}
443
444	of_node_put(root);
445	return rc;
446}
447EXPORT_SYMBOL(of_platform_bus_probe);
448
449/**
450 * of_platform_populate() - Populate platform_devices from device tree data
451 * @root: parent of the first level to probe or NULL for the root of the tree
452 * @matches: match table, NULL to use the default
453 * @lookup: auxdata table for matching id and platform_data with device nodes
454 * @parent: parent to hook devices from, NULL for toplevel
455 *
456 * Similar to of_platform_bus_probe(), this function walks the device tree
457 * and creates devices from nodes.  It differs in that it follows the modern
458 * convention of requiring all device nodes to have a 'compatible' property,
459 * and it is suitable for creating devices which are children of the root
460 * node (of_platform_bus_probe will only create children of the root which
461 * are selected by the @matches argument).
462 *
463 * New board support should be using this function instead of
464 * of_platform_bus_probe().
465 *
466 * Returns 0 on success, < 0 on failure.
467 */
468int of_platform_populate(struct device_node *root,
469			const struct of_device_id *matches,
470			const struct of_dev_auxdata *lookup,
471			struct device *parent)
472{
473	struct device_node *child;
474	int rc = 0;
475
476	root = root ? of_node_get(root) : of_find_node_by_path("/");
477	if (!root)
478		return -EINVAL;
479
480	for_each_child_of_node(root, child) {
481		rc = of_platform_bus_create(child, matches, lookup, parent, true);
482		if (rc)
 
483			break;
 
484	}
 
485
486	of_node_put(root);
487	return rc;
488}
489EXPORT_SYMBOL_GPL(of_platform_populate);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
490#endif /* CONFIG_OF_ADDRESS */
  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	{ .compatible = "simple-mfd", },
 29#ifdef CONFIG_ARM_AMBA
 30	{ .compatible = "arm,amba-bus", },
 31#endif /* CONFIG_ARM_AMBA */
 32	{} /* Empty terminated list */
 33};
 34EXPORT_SYMBOL(of_default_bus_match_table);
 35
 36static int of_dev_node_match(struct device *dev, void *data)
 37{
 38	return dev->of_node == data;
 39}
 40
 41/**
 42 * of_find_device_by_node - Find the platform_device associated with a node
 43 * @np: Pointer to device tree node
 44 *
 45 * Returns platform_device pointer, or NULL if not found
 46 */
 47struct platform_device *of_find_device_by_node(struct device_node *np)
 48{
 49	struct device *dev;
 50
 51	dev = bus_find_device(&platform_bus_type, NULL, np, of_dev_node_match);
 52	return dev ? to_platform_device(dev) : NULL;
 53}
 54EXPORT_SYMBOL(of_find_device_by_node);
 55
 
 
 
 
 56#ifdef CONFIG_OF_ADDRESS
 57/*
 58 * The following routines scan a subtree and registers a device for
 59 * each applicable node.
 60 *
 61 * Note: sparc doesn't use these routines because it has a different
 62 * mechanism for creating devices from device tree nodes.
 63 */
 64
 65/**
 66 * of_device_make_bus_id - Use the device node data to assign a unique name
 67 * @dev: pointer to device structure that is linked to a device tree node
 68 *
 69 * This routine will first try using the translated bus address to
 70 * derive a unique name. If it cannot, then it will prepend names from
 71 * parent nodes until a unique name can be derived.
 72 */
 73void of_device_make_bus_id(struct device *dev)
 74{
 
 75	struct device_node *node = dev->of_node;
 76	const __be32 *reg;
 77	u64 addr;
 
 
 78
 79	/* Construct the name, using parent nodes if necessary to ensure uniqueness */
 80	while (node->parent) {
 81		/*
 82		 * If the address can be translated, then that is as much
 83		 * uniqueness as we need. Make it the first component and return
 84		 */
 85		reg = of_get_property(node, "reg", NULL);
 86		if (reg && (addr = of_translate_address(node, reg)) != OF_BAD_ADDR) {
 87			dev_set_name(dev, dev_name(dev) ? "%llx.%s:%s" : "%llx.%s",
 88				     (unsigned long long)addr, node->name,
 89				     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			     strrchr(node->full_name, '/') + 1, 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("", -1);
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 = kzalloc(sizeof(*res) * (num_irq + num_reg), 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 %s\n",
139				 np->name);
140	}
141
142	dev->dev.of_node = of_node_get(np);
143	dev->dev.parent = parent ? : &platform_bus;
 
 
 
144
145	if (bus_id)
146		dev_set_name(&dev->dev, "%s", bus_id);
147	else
148		of_device_make_bus_id(&dev->dev);
149
150	return dev;
151}
152EXPORT_SYMBOL(of_device_alloc);
153
154static void of_dma_deconfigure(struct device *dev)
155{
156	arch_teardown_dma_ops(dev);
157}
158
159/**
160 * of_platform_device_create_pdata - Alloc, initialize and register an of_device
161 * @np: pointer to node to create device for
162 * @bus_id: name to assign device
163 * @platform_data: pointer to populate platform_data pointer with
164 * @parent: Linux device model parent device.
165 *
166 * Returns pointer to created platform device, or NULL if a device was not
167 * registered.  Unavailable devices will not get registered.
168 */
169static struct platform_device *of_platform_device_create_pdata(
170					struct device_node *np,
171					const char *bus_id,
172					void *platform_data,
173					struct device *parent)
174{
175	struct platform_device *dev;
176
177	if (!of_device_is_available(np) ||
178	    of_node_test_and_set_flag(np, OF_POPULATED))
179		return NULL;
180
181	dev = of_device_alloc(np, bus_id, parent);
182	if (!dev)
183		goto err_clear_flag;
184
 
 
 
 
 
 
185	dev->dev.bus = &platform_bus_type;
186	dev->dev.platform_data = platform_data;
187	of_dma_configure(&dev->dev, dev->dev.of_node);
188	of_msi_configure(&dev->dev, dev->dev.of_node);
 
 
 
189
190	if (of_device_add(dev) != 0) {
191		of_dma_deconfigure(&dev->dev);
192		platform_device_put(dev);
193		goto err_clear_flag;
194	}
195
196	return dev;
197
198err_clear_flag:
199	of_node_clear_flag(np, OF_POPULATED);
200	return NULL;
201}
202
203/**
204 * of_platform_device_create - Alloc, initialize and register an of_device
205 * @np: pointer to node to create device for
206 * @bus_id: name to assign device
207 * @parent: Linux device model parent device.
208 *
209 * Returns pointer to created platform device, or NULL if a device was not
210 * registered.  Unavailable devices will not get registered.
211 */
212struct platform_device *of_platform_device_create(struct device_node *np,
213					    const char *bus_id,
214					    struct device *parent)
215{
216	return of_platform_device_create_pdata(np, bus_id, NULL, parent);
217}
218EXPORT_SYMBOL(of_platform_device_create);
219
220#ifdef CONFIG_ARM_AMBA
221static struct amba_device *of_amba_device_create(struct device_node *node,
222						 const char *bus_id,
223						 void *platform_data,
224						 struct device *parent)
225{
226	struct amba_device *dev;
227	const void *prop;
228	int i, ret;
229
230	pr_debug("Creating amba device %s\n", node->full_name);
231
232	if (!of_device_is_available(node) ||
233	    of_node_test_and_set_flag(node, OF_POPULATED))
234		return NULL;
235
236	dev = amba_device_alloc(NULL, 0, 0);
237	if (!dev) {
238		pr_err("%s(): amba_device_alloc() failed for %s\n",
239		       __func__, node->full_name);
240		goto err_clear_flag;
241	}
242
243	/* setup generic device info */
 
244	dev->dev.of_node = of_node_get(node);
245	dev->dev.parent = parent ? : &platform_bus;
246	dev->dev.platform_data = platform_data;
247	if (bus_id)
248		dev_set_name(&dev->dev, "%s", bus_id);
249	else
250		of_device_make_bus_id(&dev->dev);
251	of_dma_configure(&dev->dev, dev->dev.of_node);
252
253	/* Allow the HW Peripheral ID to be overridden */
254	prop = of_get_property(node, "arm,primecell-periphid", NULL);
255	if (prop)
256		dev->periphid = of_read_ulong(prop, 1);
257
258	/* Decode the IRQs and address ranges */
259	for (i = 0; i < AMBA_NR_IRQS; i++)
260		dev->irq[i] = irq_of_parse_and_map(node, i);
261
262	ret = of_address_to_resource(node, 0, &dev->res);
263	if (ret) {
264		pr_err("%s(): of_address_to_resource() failed (%d) for %s\n",
265		       __func__, ret, node->full_name);
266		goto err_free;
267	}
268
269	ret = amba_device_add(dev, &iomem_resource);
270	if (ret) {
271		pr_err("%s(): amba_device_add() failed (%d) for %s\n",
272		       __func__, ret, node->full_name);
273		goto err_free;
274	}
275
276	return dev;
277
278err_free:
279	amba_device_put(dev);
280err_clear_flag:
281	of_node_clear_flag(node, OF_POPULATED);
282	return NULL;
283}
284#else /* CONFIG_ARM_AMBA */
285static struct amba_device *of_amba_device_create(struct device_node *node,
286						 const char *bus_id,
287						 void *platform_data,
288						 struct device *parent)
289{
290	return NULL;
291}
292#endif /* CONFIG_ARM_AMBA */
293
294/**
295 * of_devname_lookup() - Given a device node, lookup the preferred Linux name
296 */
297static const struct of_dev_auxdata *of_dev_lookup(const struct of_dev_auxdata *lookup,
298				 struct device_node *np)
299{
300	struct resource res;
301
302	if (!lookup)
303		return NULL;
304
305	for(; lookup->compatible != NULL; lookup++) {
306		if (!of_device_is_compatible(np, lookup->compatible))
307			continue;
308		if (!of_address_to_resource(np, 0, &res))
309			if (res.start != lookup->phys_addr)
310				continue;
311		pr_debug("%s: devname=%s\n", np->full_name, lookup->name);
312		return lookup;
313	}
314
315	return NULL;
316}
317
318/**
319 * of_platform_bus_create() - Create a device for a node and its children.
320 * @bus: device node of the bus to instantiate
321 * @matches: match table for bus nodes
322 * @lookup: auxdata table for matching id and platform_data with device nodes
323 * @parent: parent for new device, or NULL for top level.
324 * @strict: require compatible property
325 *
326 * Creates a platform_device for the provided device_node, and optionally
327 * recursively create devices for all the child nodes.
328 */
329static int of_platform_bus_create(struct device_node *bus,
330				  const struct of_device_id *matches,
331				  const struct of_dev_auxdata *lookup,
332				  struct device *parent, bool strict)
333{
334	const struct of_dev_auxdata *auxdata;
335	struct device_node *child;
336	struct platform_device *dev;
337	const char *bus_id = NULL;
338	void *platform_data = NULL;
339	int rc = 0;
340
341	/* Make sure it has a compatible property */
342	if (strict && (!of_get_property(bus, "compatible", NULL))) {
343		pr_debug("%s() - skipping %s, no compatible prop\n",
344			 __func__, bus->full_name);
345		return 0;
346	}
347
348	auxdata = of_dev_lookup(lookup, bus);
349	if (auxdata) {
350		bus_id = auxdata->name;
351		platform_data = auxdata->platform_data;
352	}
353
354	if (of_device_is_compatible(bus, "arm,primecell")) {
355		/*
356		 * Don't return an error here to keep compatibility with older
357		 * device tree files.
358		 */
359		of_amba_device_create(bus, bus_id, platform_data, parent);
360		return 0;
361	}
362
363	dev = of_platform_device_create_pdata(bus, bus_id, platform_data, parent);
364	if (!dev || !of_match_node(matches, bus))
365		return 0;
366
367	for_each_child_of_node(bus, child) {
368		pr_debug("   create child: %s\n", child->full_name);
369		rc = of_platform_bus_create(child, matches, lookup, &dev->dev, strict);
370		if (rc) {
371			of_node_put(child);
372			break;
373		}
374	}
375	of_node_set_flag(bus, OF_POPULATED_BUS);
376	return rc;
377}
378
379/**
380 * of_platform_bus_probe() - Probe the device-tree for platform buses
381 * @root: parent of the first level to probe or NULL for the root of the tree
382 * @matches: match table for bus nodes
383 * @parent: parent to hook devices from, NULL for toplevel
384 *
385 * Note that children of the provided root are not instantiated as devices
386 * unless the specified root itself matches the bus list and is not NULL.
387 */
388int of_platform_bus_probe(struct device_node *root,
389			  const struct of_device_id *matches,
390			  struct device *parent)
391{
392	struct device_node *child;
393	int rc = 0;
394
395	root = root ? of_node_get(root) : of_find_node_by_path("/");
396	if (!root)
397		return -EINVAL;
398
399	pr_debug("of_platform_bus_probe()\n");
400	pr_debug(" starting at: %s\n", root->full_name);
401
402	/* Do a self check of bus type, if there's a match, create children */
403	if (of_match_node(matches, root)) {
404		rc = of_platform_bus_create(root, matches, NULL, parent, false);
405	} else for_each_child_of_node(root, child) {
406		if (!of_match_node(matches, child))
407			continue;
408		rc = of_platform_bus_create(child, matches, NULL, parent, false);
409		if (rc) {
410			of_node_put(child);
411			break;
412		}
413	}
414
415	of_node_put(root);
416	return rc;
417}
418EXPORT_SYMBOL(of_platform_bus_probe);
419
420/**
421 * of_platform_populate() - Populate platform_devices from device tree data
422 * @root: parent of the first level to probe or NULL for the root of the tree
423 * @matches: match table, NULL to use the default
424 * @lookup: auxdata table for matching id and platform_data with device nodes
425 * @parent: parent to hook devices from, NULL for toplevel
426 *
427 * Similar to of_platform_bus_probe(), this function walks the device tree
428 * and creates devices from nodes.  It differs in that it follows the modern
429 * convention of requiring all device nodes to have a 'compatible' property,
430 * and it is suitable for creating devices which are children of the root
431 * node (of_platform_bus_probe will only create children of the root which
432 * are selected by the @matches argument).
433 *
434 * New board support should be using this function instead of
435 * of_platform_bus_probe().
436 *
437 * Returns 0 on success, < 0 on failure.
438 */
439int of_platform_populate(struct device_node *root,
440			const struct of_device_id *matches,
441			const struct of_dev_auxdata *lookup,
442			struct device *parent)
443{
444	struct device_node *child;
445	int rc = 0;
446
447	root = root ? of_node_get(root) : of_find_node_by_path("/");
448	if (!root)
449		return -EINVAL;
450
451	for_each_child_of_node(root, child) {
452		rc = of_platform_bus_create(child, matches, lookup, parent, true);
453		if (rc) {
454			of_node_put(child);
455			break;
456		}
457	}
458	of_node_set_flag(root, OF_POPULATED_BUS);
459
460	of_node_put(root);
461	return rc;
462}
463EXPORT_SYMBOL_GPL(of_platform_populate);
464
465int of_platform_default_populate(struct device_node *root,
466				 const struct of_dev_auxdata *lookup,
467				 struct device *parent)
468{
469	return of_platform_populate(root, of_default_bus_match_table, lookup,
470				    parent);
471}
472EXPORT_SYMBOL_GPL(of_platform_default_populate);
473
474static int of_platform_device_destroy(struct device *dev, void *data)
475{
476	/* Do not touch devices not populated from the device tree */
477	if (!dev->of_node || !of_node_check_flag(dev->of_node, OF_POPULATED))
478		return 0;
479
480	/* Recurse for any nodes that were treated as busses */
481	if (of_node_check_flag(dev->of_node, OF_POPULATED_BUS))
482		device_for_each_child(dev, NULL, of_platform_device_destroy);
483
484	if (dev->bus == &platform_bus_type)
485		platform_device_unregister(to_platform_device(dev));
486#ifdef CONFIG_ARM_AMBA
487	else if (dev->bus == &amba_bustype)
488		amba_device_unregister(to_amba_device(dev));
489#endif
490
491	of_dma_deconfigure(dev);
492	of_node_clear_flag(dev->of_node, OF_POPULATED);
493	of_node_clear_flag(dev->of_node, OF_POPULATED_BUS);
494	return 0;
495}
496
497/**
498 * of_platform_depopulate() - Remove devices populated from device tree
499 * @parent: device which children will be removed
500 *
501 * Complementary to of_platform_populate(), this function removes children
502 * of the given device (and, recurrently, their children) that have been
503 * created from their respective device tree nodes (and only those,
504 * leaving others - eg. manually created - unharmed).
505 *
506 * Returns 0 when all children devices have been removed or
507 * -EBUSY when some children remained.
508 */
509void of_platform_depopulate(struct device *parent)
510{
511	if (parent->of_node && of_node_check_flag(parent->of_node, OF_POPULATED_BUS)) {
512		device_for_each_child(parent, NULL, of_platform_device_destroy);
513		of_node_clear_flag(parent->of_node, OF_POPULATED_BUS);
514	}
515}
516EXPORT_SYMBOL_GPL(of_platform_depopulate);
517
518#ifdef CONFIG_OF_DYNAMIC
519static int of_platform_notify(struct notifier_block *nb,
520				unsigned long action, void *arg)
521{
522	struct of_reconfig_data *rd = arg;
523	struct platform_device *pdev_parent, *pdev;
524	bool children_left;
525
526	switch (of_reconfig_get_state_change(action, rd)) {
527	case OF_RECONFIG_CHANGE_ADD:
528		/* verify that the parent is a bus */
529		if (!of_node_check_flag(rd->dn->parent, OF_POPULATED_BUS))
530			return NOTIFY_OK;	/* not for us */
531
532		/* already populated? (driver using of_populate manually) */
533		if (of_node_check_flag(rd->dn, OF_POPULATED))
534			return NOTIFY_OK;
535
536		/* pdev_parent may be NULL when no bus platform device */
537		pdev_parent = of_find_device_by_node(rd->dn->parent);
538		pdev = of_platform_device_create(rd->dn, NULL,
539				pdev_parent ? &pdev_parent->dev : NULL);
540		of_dev_put(pdev_parent);
541
542		if (pdev == NULL) {
543			pr_err("%s: failed to create for '%s'\n",
544					__func__, rd->dn->full_name);
545			/* of_platform_device_create tosses the error code */
546			return notifier_from_errno(-EINVAL);
547		}
548		break;
549
550	case OF_RECONFIG_CHANGE_REMOVE:
551
552		/* already depopulated? */
553		if (!of_node_check_flag(rd->dn, OF_POPULATED))
554			return NOTIFY_OK;
555
556		/* find our device by node */
557		pdev = of_find_device_by_node(rd->dn);
558		if (pdev == NULL)
559			return NOTIFY_OK;	/* no? not meant for us */
560
561		/* unregister takes one ref away */
562		of_platform_device_destroy(&pdev->dev, &children_left);
563
564		/* and put the reference of the find */
565		of_dev_put(pdev);
566		break;
567	}
568
569	return NOTIFY_OK;
570}
571
572static struct notifier_block platform_of_notifier = {
573	.notifier_call = of_platform_notify,
574};
575
576void of_platform_register_reconfig_notifier(void)
577{
578	WARN_ON(of_reconfig_notifier_register(&platform_of_notifier));
579}
580#endif /* CONFIG_OF_DYNAMIC */
581
582#endif /* CONFIG_OF_ADDRESS */