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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 */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
v4.10.11
  1/*
  2 *    Copyright (C) 2006 Benjamin Herrenschmidt, IBM Corp.
  3 *			 <benh@kernel.crashing.org>
  4 *    and		 Arnd Bergmann, IBM Corp.
  5 *    Merged from powerpc/kernel/of_platform.c and
  6 *    sparc{,64}/kernel/of_device.c by Stephen Rothwell
  7 *
  8 *  This program is free software; you can redistribute it and/or
  9 *  modify it under the terms of the GNU General Public License
 10 *  as published by the Free Software Foundation; either version
 11 *  2 of the License, or (at your option) any later version.
 12 *
 13 */
 14
 15#define pr_fmt(fmt)	"OF: " fmt
 16
 17#include <linux/errno.h>
 18#include <linux/module.h>
 19#include <linux/amba/bus.h>
 20#include <linux/device.h>
 21#include <linux/dma-mapping.h>
 22#include <linux/slab.h>
 23#include <linux/of_address.h>
 24#include <linux/of_device.h>
 25#include <linux/of_irq.h>
 26#include <linux/of_platform.h>
 27#include <linux/platform_device.h>
 28
 29const struct of_device_id of_default_bus_match_table[] = {
 30	{ .compatible = "simple-bus", },
 31	{ .compatible = "simple-mfd", },
 32	{ .compatible = "isa", },
 33#ifdef CONFIG_ARM_AMBA
 34	{ .compatible = "arm,amba-bus", },
 35#endif /* CONFIG_ARM_AMBA */
 36	{} /* Empty terminated list */
 37};
 38
 39static int of_dev_node_match(struct device *dev, void *data)
 40{
 41	return dev->of_node == data;
 42}
 43
 44/**
 45 * of_find_device_by_node - Find the platform_device associated with a node
 46 * @np: Pointer to device tree node
 47 *
 48 * Takes a reference to the embedded struct device which needs to be dropped
 49 * after use.
 50 *
 51 * Returns platform_device pointer, or NULL if not found
 52 */
 53struct platform_device *of_find_device_by_node(struct device_node *np)
 54{
 55	struct device *dev;
 56
 57	dev = bus_find_device(&platform_bus_type, NULL, np, of_dev_node_match);
 58	return dev ? to_platform_device(dev) : NULL;
 59}
 60EXPORT_SYMBOL(of_find_device_by_node);
 61
 62#ifdef CONFIG_OF_ADDRESS
 
 
 
 
 63/*
 64 * The following routines scan a subtree and registers a device for
 65 * each applicable node.
 66 *
 67 * Note: sparc doesn't use these routines because it has a different
 68 * mechanism for creating devices from device tree nodes.
 69 */
 70
 71/**
 72 * of_device_make_bus_id - Use the device node data to assign a unique name
 73 * @dev: pointer to device structure that is linked to a device tree node
 74 *
 75 * This routine will first try using the translated bus address to
 76 * derive a unique name. If it cannot, then it will prepend names from
 77 * parent nodes until a unique name can be derived.
 78 */
 79void of_device_make_bus_id(struct device *dev)
 80{
 
 81	struct device_node *node = dev->of_node;
 82	const __be32 *reg;
 83	u64 addr;
 
 84
 85	/* Construct the name, using parent nodes if necessary to ensure uniqueness */
 86	while (node->parent) {
 87		/*
 88		 * If the address can be translated, then that is as much
 89		 * uniqueness as we need. Make it the first component and return
 90		 */
 91		reg = of_get_property(node, "reg", NULL);
 92		if (reg && (addr = of_translate_address(node, reg)) != OF_BAD_ADDR) {
 93			dev_set_name(dev, dev_name(dev) ? "%llx.%s:%s" : "%llx.%s",
 94				     (unsigned long long)addr, node->name,
 95				     dev_name(dev));
 
 
 
 96			return;
 97		}
 
 
 
 98
 99		/* format arguments only used if dev_name() resolves to NULL */
100		dev_set_name(dev, dev_name(dev) ? "%s:%s" : "%s",
101			     strrchr(node->full_name, '/') + 1, dev_name(dev));
102		node = node->parent;
 
 
 
 
 
 
 
103	}
 
 
 
 
 
 
 
104}
105
106/**
107 * of_device_alloc - Allocate and initialize an of_device
108 * @np: device node to assign to device
109 * @bus_id: Name to assign to the device.  May be null to use default name.
110 * @parent: Parent device.
111 */
112struct platform_device *of_device_alloc(struct device_node *np,
113				  const char *bus_id,
114				  struct device *parent)
115{
116	struct platform_device *dev;
117	int rc, i, num_reg = 0, num_irq;
118	struct resource *res, temp_res;
119
120	dev = platform_device_alloc("", -1);
121	if (!dev)
122		return NULL;
123
124	/* count the io and irq resources */
125	while (of_address_to_resource(np, num_reg, &temp_res) == 0)
126		num_reg++;
127	num_irq = of_irq_count(np);
128
129	/* Populate the resource table */
130	if (num_irq || num_reg) {
131		res = kzalloc(sizeof(*res) * (num_irq + num_reg), GFP_KERNEL);
132		if (!res) {
133			platform_device_put(dev);
134			return NULL;
135		}
136
137		dev->num_resources = num_reg + num_irq;
138		dev->resource = res;
139		for (i = 0; i < num_reg; i++, res++) {
140			rc = of_address_to_resource(np, i, res);
141			WARN_ON(rc);
142		}
143		if (of_irq_to_resource_table(np, res, num_irq) != num_irq)
144			pr_debug("not all legacy IRQ resources mapped for %s\n",
145				 np->name);
146	}
147
148	dev->dev.of_node = of_node_get(np);
149	dev->dev.fwnode = &np->fwnode;
150	dev->dev.parent = parent ? : &platform_bus;
 
 
151
152	if (bus_id)
153		dev_set_name(&dev->dev, "%s", bus_id);
154	else
155		of_device_make_bus_id(&dev->dev);
156
157	return dev;
158}
159EXPORT_SYMBOL(of_device_alloc);
160
161static void of_dma_deconfigure(struct device *dev)
162{
163	arch_teardown_dma_ops(dev);
164}
165
166/**
167 * of_platform_device_create_pdata - Alloc, initialize and register an of_device
168 * @np: pointer to node to create device for
169 * @bus_id: name to assign device
170 * @platform_data: pointer to populate platform_data pointer with
171 * @parent: Linux device model parent device.
172 *
173 * Returns pointer to created platform device, or NULL if a device was not
174 * registered.  Unavailable devices will not get registered.
175 */
176static struct platform_device *of_platform_device_create_pdata(
177					struct device_node *np,
178					const char *bus_id,
179					void *platform_data,
180					struct device *parent)
181{
182	struct platform_device *dev;
183
184	if (!of_device_is_available(np) ||
185	    of_node_test_and_set_flag(np, OF_POPULATED))
186		return NULL;
187
188	dev = of_device_alloc(np, bus_id, parent);
189	if (!dev)
190		goto err_clear_flag;
191
 
 
 
 
192	dev->dev.bus = &platform_bus_type;
193	dev->dev.platform_data = platform_data;
194	of_dma_configure(&dev->dev, dev->dev.of_node);
195	of_msi_configure(&dev->dev, dev->dev.of_node);
 
 
 
196
197	if (of_device_add(dev) != 0) {
198		of_dma_deconfigure(&dev->dev);
199		platform_device_put(dev);
200		goto err_clear_flag;
201	}
202
203	return dev;
204
205err_clear_flag:
206	of_node_clear_flag(np, OF_POPULATED);
207	return NULL;
208}
209
210/**
211 * of_platform_device_create - Alloc, initialize and register an of_device
212 * @np: pointer to node to create device for
213 * @bus_id: name to assign device
214 * @parent: Linux device model parent device.
215 *
216 * Returns pointer to created platform device, or NULL if a device was not
217 * registered.  Unavailable devices will not get registered.
218 */
219struct platform_device *of_platform_device_create(struct device_node *np,
220					    const char *bus_id,
221					    struct device *parent)
222{
223	return of_platform_device_create_pdata(np, bus_id, NULL, parent);
224}
225EXPORT_SYMBOL(of_platform_device_create);
226
227#ifdef CONFIG_ARM_AMBA
228static struct amba_device *of_amba_device_create(struct device_node *node,
229						 const char *bus_id,
230						 void *platform_data,
231						 struct device *parent)
232{
233	struct amba_device *dev;
234	const void *prop;
235	int i, ret;
236
237	pr_debug("Creating amba device %s\n", node->full_name);
238
239	if (!of_device_is_available(node) ||
240	    of_node_test_and_set_flag(node, OF_POPULATED))
241		return NULL;
242
243	dev = amba_device_alloc(NULL, 0, 0);
244	if (!dev)
245		goto err_clear_flag;
246
247	/* setup generic device info */
 
248	dev->dev.of_node = of_node_get(node);
249	dev->dev.fwnode = &node->fwnode;
250	dev->dev.parent = parent ? : &platform_bus;
251	dev->dev.platform_data = platform_data;
252	if (bus_id)
253		dev_set_name(&dev->dev, "%s", bus_id);
254	else
255		of_device_make_bus_id(&dev->dev);
256	of_dma_configure(&dev->dev, dev->dev.of_node);
 
 
257
258	/* Allow the HW Peripheral ID to be overridden */
259	prop = of_get_property(node, "arm,primecell-periphid", NULL);
260	if (prop)
261		dev->periphid = of_read_ulong(prop, 1);
262
263	/* Decode the IRQs and address ranges */
264	for (i = 0; i < AMBA_NR_IRQS; i++)
265		dev->irq[i] = irq_of_parse_and_map(node, i);
266
267	ret = of_address_to_resource(node, 0, &dev->res);
268	if (ret) {
269		pr_err("amba: of_address_to_resource() failed (%d) for %s\n",
270		       ret, node->full_name);
271		goto err_free;
272	}
273
274	ret = amba_device_add(dev, &iomem_resource);
275	if (ret) {
276		pr_err("amba_device_add() failed (%d) for %s\n",
277		       ret, node->full_name);
278		goto err_free;
279	}
280
281	return dev;
282
283err_free:
284	amba_device_put(dev);
285err_clear_flag:
286	of_node_clear_flag(node, OF_POPULATED);
287	return NULL;
288}
289#else /* CONFIG_ARM_AMBA */
290static struct amba_device *of_amba_device_create(struct device_node *node,
291						 const char *bus_id,
292						 void *platform_data,
293						 struct device *parent)
294{
295	return NULL;
296}
297#endif /* CONFIG_ARM_AMBA */
298
299/**
300 * of_devname_lookup() - Given a device node, lookup the preferred Linux name
301 */
302static const struct of_dev_auxdata *of_dev_lookup(const struct of_dev_auxdata *lookup,
303				 struct device_node *np)
304{
305	const struct of_dev_auxdata *auxdata;
306	struct resource res;
307	int compatible = 0;
308
309	if (!lookup)
310		return NULL;
311
312	auxdata = lookup;
313	for (; auxdata->compatible; auxdata++) {
314		if (!of_device_is_compatible(np, auxdata->compatible))
315			continue;
316		compatible++;
317		if (!of_address_to_resource(np, 0, &res))
318			if (res.start != auxdata->phys_addr)
319				continue;
320		pr_debug("%s: devname=%s\n", np->full_name, auxdata->name);
321		return auxdata;
322	}
323
324	if (!compatible)
325		return NULL;
326
327	/* Try compatible match if no phys_addr and name are specified */
328	auxdata = lookup;
329	for (; auxdata->compatible; auxdata++) {
330		if (!of_device_is_compatible(np, auxdata->compatible))
331			continue;
332		if (!auxdata->phys_addr && !auxdata->name) {
333			pr_debug("%s: compatible match\n", np->full_name);
334			return auxdata;
335		}
336	}
337
338	return NULL;
339}
340
341/**
342 * of_platform_bus_create() - Create a device for a node and its children.
343 * @bus: device node of the bus to instantiate
344 * @matches: match table for bus nodes
345 * @lookup: auxdata table for matching id and platform_data with device nodes
346 * @parent: parent for new device, or NULL for top level.
347 * @strict: require compatible property
348 *
349 * Creates a platform_device for the provided device_node, and optionally
350 * recursively create devices for all the child nodes.
351 */
352static int of_platform_bus_create(struct device_node *bus,
353				  const struct of_device_id *matches,
354				  const struct of_dev_auxdata *lookup,
355				  struct device *parent, bool strict)
356{
357	const struct of_dev_auxdata *auxdata;
358	struct device_node *child;
359	struct platform_device *dev;
360	const char *bus_id = NULL;
361	void *platform_data = NULL;
362	int rc = 0;
363
364	/* Make sure it has a compatible property */
365	if (strict && (!of_get_property(bus, "compatible", NULL))) {
366		pr_debug("%s() - skipping %s, no compatible prop\n",
367			 __func__, bus->full_name);
368		return 0;
369	}
370
371	if (of_node_check_flag(bus, OF_POPULATED_BUS)) {
372		pr_debug("%s() - skipping %s, already populated\n",
373			__func__, bus->full_name);
374		return 0;
375	}
376
377	auxdata = of_dev_lookup(lookup, bus);
378	if (auxdata) {
379		bus_id = auxdata->name;
380		platform_data = auxdata->platform_data;
381	}
382
383	if (of_device_is_compatible(bus, "arm,primecell")) {
384		/*
385		 * Don't return an error here to keep compatibility with older
386		 * device tree files.
387		 */
388		of_amba_device_create(bus, bus_id, platform_data, parent);
389		return 0;
390	}
391
392	dev = of_platform_device_create_pdata(bus, bus_id, platform_data, parent);
393	if (!dev || !of_match_node(matches, bus))
394		return 0;
395
396	for_each_child_of_node(bus, child) {
397		pr_debug("   create child: %s\n", child->full_name);
398		rc = of_platform_bus_create(child, matches, lookup, &dev->dev, strict);
399		if (rc) {
400			of_node_put(child);
401			break;
402		}
403	}
404	of_node_set_flag(bus, OF_POPULATED_BUS);
405	return rc;
406}
407
408/**
409 * of_platform_bus_probe() - Probe the device-tree for platform buses
410 * @root: parent of the first level to probe or NULL for the root of the tree
411 * @matches: match table for bus nodes
412 * @parent: parent to hook devices from, NULL for toplevel
413 *
414 * Note that children of the provided root are not instantiated as devices
415 * unless the specified root itself matches the bus list and is not NULL.
416 */
417int of_platform_bus_probe(struct device_node *root,
418			  const struct of_device_id *matches,
419			  struct device *parent)
420{
421	struct device_node *child;
422	int rc = 0;
423
424	root = root ? of_node_get(root) : of_find_node_by_path("/");
425	if (!root)
426		return -EINVAL;
427
428	pr_debug("%s()\n", __func__);
429	pr_debug(" starting at: %s\n", root->full_name);
430
431	/* Do a self check of bus type, if there's a match, create children */
432	if (of_match_node(matches, root)) {
433		rc = of_platform_bus_create(root, matches, NULL, parent, false);
434	} else for_each_child_of_node(root, child) {
435		if (!of_match_node(matches, child))
436			continue;
437		rc = of_platform_bus_create(child, matches, NULL, parent, false);
438		if (rc) {
439			of_node_put(child);
440			break;
441		}
442	}
443
444	of_node_put(root);
445	return rc;
446}
447EXPORT_SYMBOL(of_platform_bus_probe);
448
449/**
450 * of_platform_populate() - Populate platform_devices from device tree data
451 * @root: parent of the first level to probe or NULL for the root of the tree
452 * @matches: match table, NULL to use the default
453 * @lookup: auxdata table for matching id and platform_data with device nodes
454 * @parent: parent to hook devices from, NULL for toplevel
455 *
456 * Similar to of_platform_bus_probe(), this function walks the device tree
457 * and creates devices from nodes.  It differs in that it follows the modern
458 * convention of requiring all device nodes to have a 'compatible' property,
459 * and it is suitable for creating devices which are children of the root
460 * node (of_platform_bus_probe will only create children of the root which
461 * are selected by the @matches argument).
462 *
463 * New board support should be using this function instead of
464 * of_platform_bus_probe().
465 *
466 * Returns 0 on success, < 0 on failure.
467 */
468int of_platform_populate(struct device_node *root,
469			const struct of_device_id *matches,
470			const struct of_dev_auxdata *lookup,
471			struct device *parent)
472{
473	struct device_node *child;
474	int rc = 0;
475
476	root = root ? of_node_get(root) : of_find_node_by_path("/");
477	if (!root)
478		return -EINVAL;
479
480	pr_debug("%s()\n", __func__);
481	pr_debug(" starting at: %s\n", root->full_name);
482
483	for_each_child_of_node(root, child) {
484		rc = of_platform_bus_create(child, matches, lookup, parent, true);
485		if (rc) {
486			of_node_put(child);
487			break;
488		}
489	}
490	of_node_set_flag(root, OF_POPULATED_BUS);
491
492	of_node_put(root);
493	return rc;
494}
495EXPORT_SYMBOL_GPL(of_platform_populate);
496
497int of_platform_default_populate(struct device_node *root,
498				 const struct of_dev_auxdata *lookup,
499				 struct device *parent)
500{
501	return of_platform_populate(root, of_default_bus_match_table, lookup,
502				    parent);
503}
504EXPORT_SYMBOL_GPL(of_platform_default_populate);
505
506#ifndef CONFIG_PPC
507static int __init of_platform_default_populate_init(void)
508{
509	struct device_node *node;
510
511	if (!of_have_populated_dt())
512		return -ENODEV;
513
514	/*
515	 * Handle ramoops explicitly, since it is inside /reserved-memory,
516	 * which lacks a "compatible" property.
517	 */
518	node = of_find_node_by_path("/reserved-memory");
519	if (node) {
520		node = of_find_compatible_node(node, NULL, "ramoops");
521		if (node)
522			of_platform_device_create(node, NULL, NULL);
523	}
524
525	/* Populate everything else. */
526	of_platform_default_populate(NULL, NULL, NULL);
527
528	return 0;
529}
530arch_initcall_sync(of_platform_default_populate_init);
531#endif
532
533static int of_platform_device_destroy(struct device *dev, void *data)
534{
535	/* Do not touch devices not populated from the device tree */
536	if (!dev->of_node || !of_node_check_flag(dev->of_node, OF_POPULATED))
537		return 0;
538
539	/* Recurse for any nodes that were treated as busses */
540	if (of_node_check_flag(dev->of_node, OF_POPULATED_BUS))
541		device_for_each_child(dev, NULL, of_platform_device_destroy);
542
543	if (dev->bus == &platform_bus_type)
544		platform_device_unregister(to_platform_device(dev));
545#ifdef CONFIG_ARM_AMBA
546	else if (dev->bus == &amba_bustype)
547		amba_device_unregister(to_amba_device(dev));
548#endif
549
550	of_dma_deconfigure(dev);
551	of_node_clear_flag(dev->of_node, OF_POPULATED);
552	of_node_clear_flag(dev->of_node, OF_POPULATED_BUS);
553	return 0;
554}
555
556/**
557 * of_platform_depopulate() - Remove devices populated from device tree
558 * @parent: device which children will be removed
559 *
560 * Complementary to of_platform_populate(), this function removes children
561 * of the given device (and, recurrently, their children) that have been
562 * created from their respective device tree nodes (and only those,
563 * leaving others - eg. manually created - unharmed).
564 */
565void of_platform_depopulate(struct device *parent)
566{
567	if (parent->of_node && of_node_check_flag(parent->of_node, OF_POPULATED_BUS)) {
568		device_for_each_child(parent, NULL, of_platform_device_destroy);
569		of_node_clear_flag(parent->of_node, OF_POPULATED_BUS);
570	}
571}
572EXPORT_SYMBOL_GPL(of_platform_depopulate);
573
574#ifdef CONFIG_OF_DYNAMIC
575static int of_platform_notify(struct notifier_block *nb,
576				unsigned long action, void *arg)
577{
578	struct of_reconfig_data *rd = arg;
579	struct platform_device *pdev_parent, *pdev;
580	bool children_left;
581
582	switch (of_reconfig_get_state_change(action, rd)) {
583	case OF_RECONFIG_CHANGE_ADD:
584		/* verify that the parent is a bus */
585		if (!of_node_check_flag(rd->dn->parent, OF_POPULATED_BUS))
586			return NOTIFY_OK;	/* not for us */
587
588		/* already populated? (driver using of_populate manually) */
589		if (of_node_check_flag(rd->dn, OF_POPULATED))
590			return NOTIFY_OK;
591
592		/* pdev_parent may be NULL when no bus platform device */
593		pdev_parent = of_find_device_by_node(rd->dn->parent);
594		pdev = of_platform_device_create(rd->dn, NULL,
595				pdev_parent ? &pdev_parent->dev : NULL);
596		of_dev_put(pdev_parent);
597
598		if (pdev == NULL) {
599			pr_err("%s: failed to create for '%s'\n",
600					__func__, rd->dn->full_name);
601			/* of_platform_device_create tosses the error code */
602			return notifier_from_errno(-EINVAL);
603		}
604		break;
605
606	case OF_RECONFIG_CHANGE_REMOVE:
607
608		/* already depopulated? */
609		if (!of_node_check_flag(rd->dn, OF_POPULATED))
610			return NOTIFY_OK;
611
612		/* find our device by node */
613		pdev = of_find_device_by_node(rd->dn);
614		if (pdev == NULL)
615			return NOTIFY_OK;	/* no? not meant for us */
616
617		/* unregister takes one ref away */
618		of_platform_device_destroy(&pdev->dev, &children_left);
619
620		/* and put the reference of the find */
621		of_dev_put(pdev);
622		break;
623	}
624
625	return NOTIFY_OK;
626}
627
628static struct notifier_block platform_of_notifier = {
629	.notifier_call = of_platform_notify,
630};
631
632void of_platform_register_reconfig_notifier(void)
633{
634	WARN_ON(of_reconfig_notifier_register(&platform_of_notifier));
635}
636#endif /* CONFIG_OF_DYNAMIC */
637
638#endif /* CONFIG_OF_ADDRESS */