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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#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 */