Linux Audio

Check our new training course

Embedded Linux training

Mar 10-20, 2025, special US time zones
Register
Loading...
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 */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
v4.17
  1// SPDX-License-Identifier: GPL-2.0+
  2/*
  3 *    Copyright (C) 2006 Benjamin Herrenschmidt, IBM Corp.
  4 *			 <benh@kernel.crashing.org>
  5 *    and		 Arnd Bergmann, IBM Corp.
  6 *    Merged from powerpc/kernel/of_platform.c and
  7 *    sparc{,64}/kernel/of_device.c by Stephen Rothwell
 
 
 
 
 
 
  8 */
  9
 10#define pr_fmt(fmt)	"OF: " fmt
 11
 12#include <linux/errno.h>
 13#include <linux/module.h>
 14#include <linux/amba/bus.h>
 15#include <linux/device.h>
 16#include <linux/dma-mapping.h>
 17#include <linux/slab.h>
 18#include <linux/of_address.h>
 19#include <linux/of_device.h>
 20#include <linux/of_iommu.h>
 21#include <linux/of_irq.h>
 22#include <linux/of_platform.h>
 23#include <linux/platform_device.h>
 24
 25const struct of_device_id of_default_bus_match_table[] = {
 26	{ .compatible = "simple-bus", },
 27	{ .compatible = "simple-mfd", },
 28	{ .compatible = "isa", },
 29#ifdef CONFIG_ARM_AMBA
 30	{ .compatible = "arm,amba-bus", },
 31#endif /* CONFIG_ARM_AMBA */
 32	{} /* Empty terminated list */
 33};
 34
 35static int of_dev_node_match(struct device *dev, void *data)
 36{
 37	return dev->of_node == data;
 38}
 39
 40/**
 41 * of_find_device_by_node - Find the platform_device associated with a node
 42 * @np: Pointer to device tree node
 43 *
 44 * Takes a reference to the embedded struct device which needs to be dropped
 45 * after use.
 46 *
 47 * Returns platform_device pointer, or NULL if not found
 48 */
 49struct platform_device *of_find_device_by_node(struct device_node *np)
 50{
 51	struct device *dev;
 52
 53	dev = bus_find_device(&platform_bus_type, NULL, np, of_dev_node_match);
 54	return dev ? to_platform_device(dev) : NULL;
 55}
 56EXPORT_SYMBOL(of_find_device_by_node);
 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 the translated bus address to
 72 * derive a unique name. If it cannot, then it will prepend names from
 73 * parent nodes until a unique name can be derived.
 74 */
 75static void of_device_make_bus_id(struct device *dev)
 76{
 
 77	struct device_node *node = dev->of_node;
 78	const __be32 *reg;
 79	u64 addr;
 
 80
 81	/* Construct the name, using parent nodes if necessary to ensure uniqueness */
 82	while (node->parent) {
 83		/*
 84		 * If the address can be translated, then that is as much
 85		 * uniqueness as we need. Make it the first component and return
 86		 */
 87		reg = of_get_property(node, "reg", NULL);
 88		if (reg && (addr = of_translate_address(node, reg)) != OF_BAD_ADDR) {
 89			dev_set_name(dev, dev_name(dev) ? "%llx.%s:%s" : "%llx.%s",
 90				     (unsigned long long)addr, node->name,
 91				     dev_name(dev));
 
 
 
 92			return;
 93		}
 
 
 
 94
 95		/* format arguments only used if dev_name() resolves to NULL */
 96		dev_set_name(dev, dev_name(dev) ? "%s:%s" : "%s",
 97			     kbasename(node->full_name), dev_name(dev));
 98		node = node->parent;
 
 
 
 
 
 
 
 99	}
 
 
 
 
 
 
 
100}
101
102/**
103 * of_device_alloc - Allocate and initialize an of_device
104 * @np: device node to assign to device
105 * @bus_id: Name to assign to the device.  May be null to use default name.
106 * @parent: Parent device.
107 */
108struct platform_device *of_device_alloc(struct device_node *np,
109				  const char *bus_id,
110				  struct device *parent)
111{
112	struct platform_device *dev;
113	int rc, i, num_reg = 0, num_irq;
114	struct resource *res, temp_res;
115
116	dev = platform_device_alloc("", PLATFORM_DEVID_NONE);
117	if (!dev)
118		return NULL;
119
120	/* count the io and irq resources */
121	while (of_address_to_resource(np, num_reg, &temp_res) == 0)
122		num_reg++;
123	num_irq = of_irq_count(np);
124
125	/* Populate the resource table */
126	if (num_irq || num_reg) {
127		res = kzalloc(sizeof(*res) * (num_irq + num_reg), GFP_KERNEL);
128		if (!res) {
129			platform_device_put(dev);
130			return NULL;
131		}
132
133		dev->num_resources = num_reg + num_irq;
134		dev->resource = res;
135		for (i = 0; i < num_reg; i++, res++) {
136			rc = of_address_to_resource(np, i, res);
137			WARN_ON(rc);
138		}
139		if (of_irq_to_resource_table(np, res, num_irq) != num_irq)
140			pr_debug("not all legacy IRQ resources mapped for %s\n",
141				 np->name);
142	}
143
144	dev->dev.of_node = of_node_get(np);
145	dev->dev.fwnode = &np->fwnode;
146	dev->dev.parent = parent ? : &platform_bus;
 
 
147
148	if (bus_id)
149		dev_set_name(&dev->dev, "%s", bus_id);
150	else
151		of_device_make_bus_id(&dev->dev);
152
153	return dev;
154}
155EXPORT_SYMBOL(of_device_alloc);
156
157/**
158 * of_platform_device_create_pdata - Alloc, initialize and register an of_device
159 * @np: pointer to node to create device for
160 * @bus_id: name to assign device
161 * @platform_data: pointer to populate platform_data pointer with
162 * @parent: Linux device model parent device.
163 *
164 * Returns pointer to created platform device, or NULL if a device was not
165 * registered.  Unavailable devices will not get registered.
166 */
167static struct platform_device *of_platform_device_create_pdata(
168					struct device_node *np,
169					const char *bus_id,
170					void *platform_data,
171					struct device *parent)
172{
173	struct platform_device *dev;
174
175	if (!of_device_is_available(np) ||
176	    of_node_test_and_set_flag(np, OF_POPULATED))
177		return NULL;
178
179	dev = of_device_alloc(np, bus_id, parent);
180	if (!dev)
181		goto err_clear_flag;
182
 
 
 
 
183	dev->dev.bus = &platform_bus_type;
184	dev->dev.platform_data = platform_data;
185	of_msi_configure(&dev->dev, dev->dev.of_node);
 
 
 
 
186
187	if (of_device_add(dev) != 0) {
188		platform_device_put(dev);
189		goto err_clear_flag;
190	}
191
192	return dev;
193
194err_clear_flag:
195	of_node_clear_flag(np, OF_POPULATED);
196	return NULL;
197}
198
199/**
200 * of_platform_device_create - Alloc, initialize and register an of_device
201 * @np: pointer to node to create device for
202 * @bus_id: name to assign device
203 * @parent: Linux device model parent device.
204 *
205 * Returns pointer to created platform device, or NULL if a device was not
206 * registered.  Unavailable devices will not get registered.
207 */
208struct platform_device *of_platform_device_create(struct device_node *np,
209					    const char *bus_id,
210					    struct device *parent)
211{
212	return of_platform_device_create_pdata(np, bus_id, NULL, parent);
213}
214EXPORT_SYMBOL(of_platform_device_create);
215
216#ifdef CONFIG_ARM_AMBA
217static struct amba_device *of_amba_device_create(struct device_node *node,
218						 const char *bus_id,
219						 void *platform_data,
220						 struct device *parent)
221{
222	struct amba_device *dev;
223	const void *prop;
224	int i, ret;
225
226	pr_debug("Creating amba device %pOF\n", node);
227
228	if (!of_device_is_available(node) ||
229	    of_node_test_and_set_flag(node, OF_POPULATED))
230		return NULL;
231
232	dev = amba_device_alloc(NULL, 0, 0);
233	if (!dev)
234		goto err_clear_flag;
235
236	/* setup generic device info */
 
237	dev->dev.of_node = of_node_get(node);
238	dev->dev.fwnode = &node->fwnode;
239	dev->dev.parent = parent ? : &platform_bus;
240	dev->dev.platform_data = platform_data;
241	if (bus_id)
242		dev_set_name(&dev->dev, "%s", bus_id);
243	else
244		of_device_make_bus_id(&dev->dev);
245
 
 
 
246	/* Allow the HW Peripheral ID to be overridden */
247	prop = of_get_property(node, "arm,primecell-periphid", NULL);
248	if (prop)
249		dev->periphid = of_read_ulong(prop, 1);
250
251	/* Decode the IRQs and address ranges */
252	for (i = 0; i < AMBA_NR_IRQS; i++)
253		dev->irq[i] = irq_of_parse_and_map(node, i);
254
255	ret = of_address_to_resource(node, 0, &dev->res);
256	if (ret) {
257		pr_err("amba: of_address_to_resource() failed (%d) for %pOF\n",
258		       ret, node);
259		goto err_free;
260	}
261
262	ret = amba_device_add(dev, &iomem_resource);
263	if (ret) {
264		pr_err("amba_device_add() failed (%d) for %pOF\n",
265		       ret, node);
266		goto err_free;
267	}
268
269	return dev;
270
271err_free:
272	amba_device_put(dev);
273err_clear_flag:
274	of_node_clear_flag(node, OF_POPULATED);
275	return NULL;
276}
277#else /* CONFIG_ARM_AMBA */
278static struct amba_device *of_amba_device_create(struct device_node *node,
279						 const char *bus_id,
280						 void *platform_data,
281						 struct device *parent)
282{
283	return NULL;
284}
285#endif /* CONFIG_ARM_AMBA */
286
287/**
288 * of_devname_lookup() - Given a device node, lookup the preferred Linux name
289 */
290static const struct of_dev_auxdata *of_dev_lookup(const struct of_dev_auxdata *lookup,
291				 struct device_node *np)
292{
293	const struct of_dev_auxdata *auxdata;
294	struct resource res;
295	int compatible = 0;
296
297	if (!lookup)
298		return NULL;
299
300	auxdata = lookup;
301	for (; auxdata->compatible; auxdata++) {
302		if (!of_device_is_compatible(np, auxdata->compatible))
303			continue;
304		compatible++;
305		if (!of_address_to_resource(np, 0, &res))
306			if (res.start != auxdata->phys_addr)
307				continue;
308		pr_debug("%pOF: devname=%s\n", np, auxdata->name);
309		return auxdata;
310	}
311
312	if (!compatible)
313		return NULL;
314
315	/* Try compatible match if no phys_addr and name are specified */
316	auxdata = lookup;
317	for (; auxdata->compatible; auxdata++) {
318		if (!of_device_is_compatible(np, auxdata->compatible))
319			continue;
320		if (!auxdata->phys_addr && !auxdata->name) {
321			pr_debug("%pOF: compatible match\n", np);
322			return auxdata;
323		}
324	}
325
326	return NULL;
327}
328
329/**
330 * of_platform_bus_create() - Create a device for a node and its children.
331 * @bus: device node of the bus to instantiate
332 * @matches: match table for bus nodes
333 * @lookup: auxdata table for matching id and platform_data with device nodes
334 * @parent: parent for new device, or NULL for top level.
335 * @strict: require compatible property
336 *
337 * Creates a platform_device for the provided device_node, and optionally
338 * recursively create devices for all the child nodes.
339 */
340static int of_platform_bus_create(struct device_node *bus,
341				  const struct of_device_id *matches,
342				  const struct of_dev_auxdata *lookup,
343				  struct device *parent, bool strict)
344{
345	const struct of_dev_auxdata *auxdata;
346	struct device_node *child;
347	struct platform_device *dev;
348	const char *bus_id = NULL;
349	void *platform_data = NULL;
350	int rc = 0;
351
352	/* Make sure it has a compatible property */
353	if (strict && (!of_get_property(bus, "compatible", NULL))) {
354		pr_debug("%s() - skipping %pOF, no compatible prop\n",
355			 __func__, bus);
356		return 0;
357	}
358
359	if (of_node_check_flag(bus, OF_POPULATED_BUS)) {
360		pr_debug("%s() - skipping %pOF, already populated\n",
361			__func__, bus);
362		return 0;
363	}
364
365	auxdata = of_dev_lookup(lookup, bus);
366	if (auxdata) {
367		bus_id = auxdata->name;
368		platform_data = auxdata->platform_data;
369	}
370
371	if (of_device_is_compatible(bus, "arm,primecell")) {
372		/*
373		 * Don't return an error here to keep compatibility with older
374		 * device tree files.
375		 */
376		of_amba_device_create(bus, bus_id, platform_data, parent);
377		return 0;
378	}
379
380	dev = of_platform_device_create_pdata(bus, bus_id, platform_data, parent);
381	if (!dev || !of_match_node(matches, bus))
382		return 0;
383
384	for_each_child_of_node(bus, child) {
385		pr_debug("   create child: %pOF\n", child);
386		rc = of_platform_bus_create(child, matches, lookup, &dev->dev, strict);
387		if (rc) {
388			of_node_put(child);
389			break;
390		}
391	}
392	of_node_set_flag(bus, OF_POPULATED_BUS);
393	return rc;
394}
395
396/**
397 * of_platform_bus_probe() - Probe the device-tree for platform buses
398 * @root: parent of the first level to probe or NULL for the root of the tree
399 * @matches: match table for bus nodes
400 * @parent: parent to hook devices from, NULL for toplevel
401 *
402 * Note that children of the provided root are not instantiated as devices
403 * unless the specified root itself matches the bus list and is not NULL.
404 */
405int of_platform_bus_probe(struct device_node *root,
406			  const struct of_device_id *matches,
407			  struct device *parent)
408{
409	struct device_node *child;
410	int rc = 0;
411
412	root = root ? of_node_get(root) : of_find_node_by_path("/");
413	if (!root)
414		return -EINVAL;
415
416	pr_debug("%s()\n", __func__);
417	pr_debug(" starting at: %pOF\n", root);
418
419	/* Do a self check of bus type, if there's a match, create children */
420	if (of_match_node(matches, root)) {
421		rc = of_platform_bus_create(root, matches, NULL, parent, false);
422	} else for_each_child_of_node(root, child) {
423		if (!of_match_node(matches, child))
424			continue;
425		rc = of_platform_bus_create(child, matches, NULL, parent, false);
426		if (rc) {
427			of_node_put(child);
428			break;
429		}
430	}
431
432	of_node_put(root);
433	return rc;
434}
435EXPORT_SYMBOL(of_platform_bus_probe);
436
437/**
438 * of_platform_populate() - Populate platform_devices from device tree data
439 * @root: parent of the first level to probe or NULL for the root of the tree
440 * @matches: match table, NULL to use the default
441 * @lookup: auxdata table for matching id and platform_data with device nodes
442 * @parent: parent to hook devices from, NULL for toplevel
443 *
444 * Similar to of_platform_bus_probe(), this function walks the device tree
445 * and creates devices from nodes.  It differs in that it follows the modern
446 * convention of requiring all device nodes to have a 'compatible' property,
447 * and it is suitable for creating devices which are children of the root
448 * node (of_platform_bus_probe will only create children of the root which
449 * are selected by the @matches argument).
450 *
451 * New board support should be using this function instead of
452 * of_platform_bus_probe().
453 *
454 * Returns 0 on success, < 0 on failure.
455 */
456int of_platform_populate(struct device_node *root,
457			const struct of_device_id *matches,
458			const struct of_dev_auxdata *lookup,
459			struct device *parent)
460{
461	struct device_node *child;
462	int rc = 0;
463
464	root = root ? of_node_get(root) : of_find_node_by_path("/");
465	if (!root)
466		return -EINVAL;
467
468	pr_debug("%s()\n", __func__);
469	pr_debug(" starting at: %pOF\n", root);
470
471	for_each_child_of_node(root, child) {
472		rc = of_platform_bus_create(child, matches, lookup, parent, true);
473		if (rc) {
474			of_node_put(child);
475			break;
476		}
477	}
478	of_node_set_flag(root, OF_POPULATED_BUS);
479
480	of_node_put(root);
481	return rc;
482}
483EXPORT_SYMBOL_GPL(of_platform_populate);
484
485int of_platform_default_populate(struct device_node *root,
486				 const struct of_dev_auxdata *lookup,
487				 struct device *parent)
488{
489	return of_platform_populate(root, of_default_bus_match_table, lookup,
490				    parent);
491}
492EXPORT_SYMBOL_GPL(of_platform_default_populate);
493
494#ifndef CONFIG_PPC
495static const struct of_device_id reserved_mem_matches[] = {
496	{ .compatible = "qcom,rmtfs-mem" },
497	{ .compatible = "ramoops" },
498	{}
499};
500
501static int __init of_platform_default_populate_init(void)
502{
503	struct device_node *node;
504
505	if (!of_have_populated_dt())
506		return -ENODEV;
507
508	/*
509	 * Handle certain compatibles explicitly, since we don't want to create
510	 * platform_devices for every node in /reserved-memory with a
511	 * "compatible",
512	 */
513	for_each_matching_node(node, reserved_mem_matches)
514		of_platform_device_create(node, NULL, NULL);
515
516	node = of_find_node_by_path("/firmware");
517	if (node) {
518		of_platform_populate(node, NULL, NULL, NULL);
519		of_node_put(node);
520	}
521
522	/* Populate everything else. */
523	of_platform_default_populate(NULL, NULL, NULL);
524
525	return 0;
526}
527arch_initcall_sync(of_platform_default_populate_init);
528#endif
529
530int of_platform_device_destroy(struct device *dev, void *data)
531{
532	/* Do not touch devices not populated from the device tree */
533	if (!dev->of_node || !of_node_check_flag(dev->of_node, OF_POPULATED))
534		return 0;
535
536	/* Recurse for any nodes that were treated as busses */
537	if (of_node_check_flag(dev->of_node, OF_POPULATED_BUS))
538		device_for_each_child(dev, NULL, of_platform_device_destroy);
539
540	if (dev->bus == &platform_bus_type)
541		platform_device_unregister(to_platform_device(dev));
542#ifdef CONFIG_ARM_AMBA
543	else if (dev->bus == &amba_bustype)
544		amba_device_unregister(to_amba_device(dev));
545#endif
546
547	of_node_clear_flag(dev->of_node, OF_POPULATED);
548	of_node_clear_flag(dev->of_node, OF_POPULATED_BUS);
549	return 0;
550}
551EXPORT_SYMBOL_GPL(of_platform_device_destroy);
552
553/**
554 * of_platform_depopulate() - Remove devices populated from device tree
555 * @parent: device which children will be removed
556 *
557 * Complementary to of_platform_populate(), this function removes children
558 * of the given device (and, recurrently, their children) that have been
559 * created from their respective device tree nodes (and only those,
560 * leaving others - eg. manually created - unharmed).
561 */
562void of_platform_depopulate(struct device *parent)
563{
564	if (parent->of_node && of_node_check_flag(parent->of_node, OF_POPULATED_BUS)) {
565		device_for_each_child(parent, NULL, of_platform_device_destroy);
566		of_node_clear_flag(parent->of_node, OF_POPULATED_BUS);
567	}
568}
569EXPORT_SYMBOL_GPL(of_platform_depopulate);
570
571static void devm_of_platform_populate_release(struct device *dev, void *res)
572{
573	of_platform_depopulate(*(struct device **)res);
574}
575
576/**
577 * devm_of_platform_populate() - Populate platform_devices from device tree data
578 * @dev: device that requested to populate from device tree data
579 *
580 * Similar to of_platform_populate(), but will automatically call
581 * of_platform_depopulate() when the device is unbound from the bus.
582 *
583 * Returns 0 on success, < 0 on failure.
584 */
585int devm_of_platform_populate(struct device *dev)
586{
587	struct device **ptr;
588	int ret;
589
590	if (!dev)
591		return -EINVAL;
592
593	ptr = devres_alloc(devm_of_platform_populate_release,
594			   sizeof(*ptr), GFP_KERNEL);
595	if (!ptr)
596		return -ENOMEM;
597
598	ret = of_platform_populate(dev->of_node, NULL, NULL, dev);
599	if (ret) {
600		devres_free(ptr);
601	} else {
602		*ptr = dev;
603		devres_add(dev, ptr);
604	}
605
606	return ret;
607}
608EXPORT_SYMBOL_GPL(devm_of_platform_populate);
609
610static int devm_of_platform_match(struct device *dev, void *res, void *data)
611{
612	struct device **ptr = res;
613
614	if (!ptr) {
615		WARN_ON(!ptr);
616		return 0;
617	}
618
619	return *ptr == data;
620}
621
622/**
623 * devm_of_platform_depopulate() - Remove devices populated from device tree
624 * @dev: device that requested to depopulate from device tree data
625 *
626 * Complementary to devm_of_platform_populate(), this function removes children
627 * of the given device (and, recurrently, their children) that have been
628 * created from their respective device tree nodes (and only those,
629 * leaving others - eg. manually created - unharmed).
630 */
631void devm_of_platform_depopulate(struct device *dev)
632{
633	int ret;
634
635	ret = devres_release(dev, devm_of_platform_populate_release,
636			     devm_of_platform_match, dev);
637
638	WARN_ON(ret);
639}
640EXPORT_SYMBOL_GPL(devm_of_platform_depopulate);
641
642#ifdef CONFIG_OF_DYNAMIC
643static int of_platform_notify(struct notifier_block *nb,
644				unsigned long action, void *arg)
645{
646	struct of_reconfig_data *rd = arg;
647	struct platform_device *pdev_parent, *pdev;
648	bool children_left;
649
650	switch (of_reconfig_get_state_change(action, rd)) {
651	case OF_RECONFIG_CHANGE_ADD:
652		/* verify that the parent is a bus */
653		if (!of_node_check_flag(rd->dn->parent, OF_POPULATED_BUS))
654			return NOTIFY_OK;	/* not for us */
655
656		/* already populated? (driver using of_populate manually) */
657		if (of_node_check_flag(rd->dn, OF_POPULATED))
658			return NOTIFY_OK;
659
660		/* pdev_parent may be NULL when no bus platform device */
661		pdev_parent = of_find_device_by_node(rd->dn->parent);
662		pdev = of_platform_device_create(rd->dn, NULL,
663				pdev_parent ? &pdev_parent->dev : NULL);
664		of_dev_put(pdev_parent);
665
666		if (pdev == NULL) {
667			pr_err("%s: failed to create for '%pOF'\n",
668					__func__, rd->dn);
669			/* of_platform_device_create tosses the error code */
670			return notifier_from_errno(-EINVAL);
671		}
672		break;
673
674	case OF_RECONFIG_CHANGE_REMOVE:
675
676		/* already depopulated? */
677		if (!of_node_check_flag(rd->dn, OF_POPULATED))
678			return NOTIFY_OK;
679
680		/* find our device by node */
681		pdev = of_find_device_by_node(rd->dn);
682		if (pdev == NULL)
683			return NOTIFY_OK;	/* no? not meant for us */
684
685		/* unregister takes one ref away */
686		of_platform_device_destroy(&pdev->dev, &children_left);
687
688		/* and put the reference of the find */
689		of_dev_put(pdev);
690		break;
691	}
692
693	return NOTIFY_OK;
694}
695
696static struct notifier_block platform_of_notifier = {
697	.notifier_call = of_platform_notify,
698};
699
700void of_platform_register_reconfig_notifier(void)
701{
702	WARN_ON(of_reconfig_notifier_register(&platform_of_notifier));
703}
704#endif /* CONFIG_OF_DYNAMIC */
705
706#endif /* CONFIG_OF_ADDRESS */