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v3.15
  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 */
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 */