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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 */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
v6.9.4
  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_irq.h>
 21#include <linux/of_platform.h>
 22#include <linux/platform_device.h>
 23#include <linux/sysfb.h>
 24
 25#include "of_private.h"
 26
 27const struct of_device_id of_default_bus_match_table[] = {
 28	{ .compatible = "simple-bus", },
 29	{ .compatible = "simple-mfd", },
 30	{ .compatible = "isa", },
 31#ifdef CONFIG_ARM_AMBA
 32	{ .compatible = "arm,amba-bus", },
 33#endif /* CONFIG_ARM_AMBA */
 34	{} /* Empty terminated list */
 35};
 36
 
 
 
 
 
 37/**
 38 * of_find_device_by_node - Find the platform_device associated with a node
 39 * @np: Pointer to device tree node
 40 *
 41 * Takes a reference to the embedded struct device which needs to be dropped
 42 * after use.
 43 *
 44 * Return: platform_device pointer, or NULL if not found
 45 */
 46struct platform_device *of_find_device_by_node(struct device_node *np)
 47{
 48	struct device *dev;
 49
 50	dev = bus_find_device_by_of_node(&platform_bus_type, np);
 51	return dev ? to_platform_device(dev) : NULL;
 52}
 53EXPORT_SYMBOL(of_find_device_by_node);
 54
 55int of_device_add(struct platform_device *ofdev)
 56{
 57	BUG_ON(ofdev->dev.of_node == NULL);
 58
 59	/* name and id have to be set so that the platform bus doesn't get
 60	 * confused on matching */
 61	ofdev->name = dev_name(&ofdev->dev);
 62	ofdev->id = PLATFORM_DEVID_NONE;
 63
 64	/*
 65	 * If this device has not binding numa node in devicetree, that is
 66	 * of_node_to_nid returns NUMA_NO_NODE. device_add will assume that this
 67	 * device is on the same node as the parent.
 68	 */
 69	set_dev_node(&ofdev->dev, of_node_to_nid(ofdev->dev.of_node));
 70
 71	return device_add(&ofdev->dev);
 72}
 73
 74int of_device_register(struct platform_device *pdev)
 75{
 76	device_initialize(&pdev->dev);
 77	return of_device_add(pdev);
 78}
 79EXPORT_SYMBOL(of_device_register);
 80
 81void of_device_unregister(struct platform_device *ofdev)
 82{
 83	device_unregister(&ofdev->dev);
 84}
 85EXPORT_SYMBOL(of_device_unregister);
 86
 87#ifdef CONFIG_OF_ADDRESS
 88static const struct of_device_id of_skipped_node_table[] = {
 89	{ .compatible = "operating-points-v2", },
 90	{} /* Empty terminated list */
 91};
 92
 
 93/*
 94 * The following routines scan a subtree and registers a device for
 95 * each applicable node.
 96 *
 97 * Note: sparc doesn't use these routines because it has a different
 98 * mechanism for creating devices from device tree nodes.
 99 */
100
101/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
102 * of_device_alloc - Allocate and initialize an of_device
103 * @np: device node to assign to device
104 * @bus_id: Name to assign to the device.  May be null to use default name.
105 * @parent: Parent device.
106 */
107struct platform_device *of_device_alloc(struct device_node *np,
108				  const char *bus_id,
109				  struct device *parent)
110{
111	struct platform_device *dev;
112	int rc, i, num_reg = 0;
113	struct resource *res;
114
115	dev = platform_device_alloc("", PLATFORM_DEVID_NONE);
116	if (!dev)
117		return NULL;
118
119	/* count the io resources */
120	num_reg = of_address_count(np);
 
 
121
122	/* Populate the resource table */
123	if (num_reg) {
124		res = kcalloc(num_reg, sizeof(*res), GFP_KERNEL);
125		if (!res) {
126			platform_device_put(dev);
127			return NULL;
128		}
129
130		dev->num_resources = num_reg;
131		dev->resource = res;
132		for (i = 0; i < num_reg; i++, res++) {
133			rc = of_address_to_resource(np, i, res);
134			WARN_ON(rc);
135		}
 
136	}
137
138	/* setup generic device info */
139	device_set_node(&dev->dev, of_fwnode_handle(of_node_get(np)));
140	dev->dev.parent = parent ? : &platform_bus;
 
 
141
142	if (bus_id)
143		dev_set_name(&dev->dev, "%s", bus_id);
144	else
145		of_device_make_bus_id(&dev->dev);
146
147	return dev;
148}
149EXPORT_SYMBOL(of_device_alloc);
150
151/**
152 * of_platform_device_create_pdata - Alloc, initialize and register an of_device
153 * @np: pointer to node to create device for
154 * @bus_id: name to assign device
155 * @platform_data: pointer to populate platform_data pointer with
156 * @parent: Linux device model parent device.
157 *
158 * Return: Pointer to created platform device, or NULL if a device was not
159 * registered.  Unavailable devices will not get registered.
160 */
161static struct platform_device *of_platform_device_create_pdata(
162					struct device_node *np,
163					const char *bus_id,
164					void *platform_data,
165					struct device *parent)
166{
167	struct platform_device *dev;
168
169	pr_debug("create platform device: %pOF\n", np);
170
171	if (!of_device_is_available(np) ||
172	    of_node_test_and_set_flag(np, OF_POPULATED))
173		return NULL;
174
175	dev = of_device_alloc(np, bus_id, parent);
176	if (!dev)
177		goto err_clear_flag;
178
 
 
 
179	dev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
180	if (!dev->dev.dma_mask)
181		dev->dev.dma_mask = &dev->dev.coherent_dma_mask;
182	dev->dev.bus = &platform_bus_type;
183	dev->dev.platform_data = platform_data;
184	of_msi_configure(&dev->dev, dev->dev.of_node);
 
 
 
 
185
186	if (of_device_add(dev) != 0) {
187		platform_device_put(dev);
188		goto err_clear_flag;
189	}
190
191	return dev;
192
193err_clear_flag:
194	of_node_clear_flag(np, OF_POPULATED);
195	return NULL;
196}
197
198/**
199 * of_platform_device_create - Alloc, initialize and register an of_device
200 * @np: pointer to node to create device for
201 * @bus_id: name to assign device
202 * @parent: Linux device model parent device.
203 *
204 * Return: Pointer to created platform device, or NULL if a device was not
205 * registered.  Unavailable devices will not get registered.
206 */
207struct platform_device *of_platform_device_create(struct device_node *np,
208					    const char *bus_id,
209					    struct device *parent)
210{
211	return of_platform_device_create_pdata(np, bus_id, NULL, parent);
212}
213EXPORT_SYMBOL(of_platform_device_create);
214
215#ifdef CONFIG_ARM_AMBA
216static struct amba_device *of_amba_device_create(struct device_node *node,
217						 const char *bus_id,
218						 void *platform_data,
219						 struct device *parent)
220{
221	struct amba_device *dev;
222	int ret;
 
223
224	pr_debug("Creating amba device %pOF\n", node);
225
226	if (!of_device_is_available(node) ||
227	    of_node_test_and_set_flag(node, OF_POPULATED))
228		return NULL;
229
230	dev = amba_device_alloc(NULL, 0, 0);
231	if (!dev)
232		goto err_clear_flag;
233
234	/* AMBA devices only support a single DMA mask */
235	dev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
236	dev->dev.dma_mask = &dev->dev.coherent_dma_mask;
237
238	/* setup generic device info */
239	device_set_node(&dev->dev, of_fwnode_handle(node));
240	dev->dev.parent = parent ? : &platform_bus;
 
241	dev->dev.platform_data = platform_data;
242	if (bus_id)
243		dev_set_name(&dev->dev, "%s", bus_id);
244	else
245		of_device_make_bus_id(&dev->dev);
246
 
 
 
247	/* Allow the HW Peripheral ID to be overridden */
248	of_property_read_u32(node, "arm,primecell-periphid", &dev->periphid);
 
 
 
 
 
 
249
250	ret = of_address_to_resource(node, 0, &dev->res);
251	if (ret) {
252		pr_err("amba: of_address_to_resource() failed (%d) for %pOF\n",
253		       ret, node);
254		goto err_free;
255	}
256
257	ret = amba_device_add(dev, &iomem_resource);
258	if (ret) {
259		pr_err("amba_device_add() failed (%d) for %pOF\n",
260		       ret, node);
261		goto err_free;
262	}
263
264	return dev;
265
266err_free:
267	amba_device_put(dev);
268err_clear_flag:
269	of_node_clear_flag(node, OF_POPULATED);
270	return NULL;
271}
272#else /* CONFIG_ARM_AMBA */
273static struct amba_device *of_amba_device_create(struct device_node *node,
274						 const char *bus_id,
275						 void *platform_data,
276						 struct device *parent)
277{
278	return NULL;
279}
280#endif /* CONFIG_ARM_AMBA */
281
282/*
283 * of_dev_lookup() - Given a device node, lookup the preferred Linux name
284 */
285static const struct of_dev_auxdata *of_dev_lookup(const struct of_dev_auxdata *lookup,
286				 struct device_node *np)
287{
288	const struct of_dev_auxdata *auxdata;
289	struct resource res;
290	int compatible = 0;
291
292	if (!lookup)
293		return NULL;
294
295	auxdata = lookup;
296	for (; auxdata->compatible; auxdata++) {
297		if (!of_device_is_compatible(np, auxdata->compatible))
298			continue;
299		compatible++;
300		if (!of_address_to_resource(np, 0, &res))
301			if (res.start != auxdata->phys_addr)
302				continue;
303		pr_debug("%pOF: devname=%s\n", np, auxdata->name);
304		return auxdata;
305	}
306
307	if (!compatible)
308		return NULL;
309
310	/* Try compatible match if no phys_addr and name are specified */
311	auxdata = lookup;
312	for (; auxdata->compatible; auxdata++) {
313		if (!of_device_is_compatible(np, auxdata->compatible))
314			continue;
315		if (!auxdata->phys_addr && !auxdata->name) {
316			pr_debug("%pOF: compatible match\n", np);
317			return auxdata;
318		}
319	}
320
321	return NULL;
322}
323
324/**
325 * of_platform_bus_create() - Create a device for a node and its children.
326 * @bus: device node of the bus to instantiate
327 * @matches: match table for bus nodes
328 * @lookup: auxdata table for matching id and platform_data with device nodes
329 * @parent: parent for new device, or NULL for top level.
330 * @strict: require compatible property
331 *
332 * Creates a platform_device for the provided device_node, and optionally
333 * recursively create devices for all the child nodes.
334 */
335static int of_platform_bus_create(struct device_node *bus,
336				  const struct of_device_id *matches,
337				  const struct of_dev_auxdata *lookup,
338				  struct device *parent, bool strict)
339{
340	const struct of_dev_auxdata *auxdata;
341	struct device_node *child;
342	struct platform_device *dev;
343	const char *bus_id = NULL;
344	void *platform_data = NULL;
345	int rc = 0;
346
347	/* Make sure it has a compatible property */
348	if (strict && (!of_get_property(bus, "compatible", NULL))) {
349		pr_debug("%s() - skipping %pOF, no compatible prop\n",
350			 __func__, bus);
351		return 0;
352	}
353
354	/* Skip nodes for which we don't want to create devices */
355	if (unlikely(of_match_node(of_skipped_node_table, bus))) {
356		pr_debug("%s() - skipping %pOF node\n", __func__, bus);
357		return 0;
358	}
359
360	if (of_node_check_flag(bus, OF_POPULATED_BUS)) {
361		pr_debug("%s() - skipping %pOF, already populated\n",
362			__func__, bus);
363		return 0;
364	}
365
366	auxdata = of_dev_lookup(lookup, bus);
367	if (auxdata) {
368		bus_id = auxdata->name;
369		platform_data = auxdata->platform_data;
370	}
371
372	if (of_device_is_compatible(bus, "arm,primecell")) {
373		/*
374		 * Don't return an error here to keep compatibility with older
375		 * device tree files.
376		 */
377		of_amba_device_create(bus, bus_id, platform_data, parent);
378		return 0;
379	}
380
381	dev = of_platform_device_create_pdata(bus, bus_id, platform_data, parent);
382	if (!dev || !of_match_node(matches, bus))
383		return 0;
384
385	for_each_child_of_node(bus, child) {
386		pr_debug("   create child: %pOF\n", child);
387		rc = of_platform_bus_create(child, matches, lookup, &dev->dev, strict);
388		if (rc) {
389			of_node_put(child);
390			break;
391		}
392	}
393	of_node_set_flag(bus, OF_POPULATED_BUS);
394	return rc;
395}
396
397/**
398 * of_platform_bus_probe() - Probe the device-tree for platform buses
399 * @root: parent of the first level to probe or NULL for the root of the tree
400 * @matches: match table for bus nodes
401 * @parent: parent to hook devices from, NULL for toplevel
402 *
403 * Note that children of the provided root are not instantiated as devices
404 * unless the specified root itself matches the bus list and is not NULL.
405 */
406int of_platform_bus_probe(struct device_node *root,
407			  const struct of_device_id *matches,
408			  struct device *parent)
409{
410	struct device_node *child;
411	int rc = 0;
412
413	root = root ? of_node_get(root) : of_find_node_by_path("/");
414	if (!root)
415		return -EINVAL;
416
417	pr_debug("%s()\n", __func__);
418	pr_debug(" starting at: %pOF\n", root);
419
420	/* Do a self check of bus type, if there's a match, create children */
421	if (of_match_node(matches, root)) {
422		rc = of_platform_bus_create(root, matches, NULL, parent, false);
423	} else for_each_child_of_node(root, child) {
424		if (!of_match_node(matches, child))
425			continue;
426		rc = of_platform_bus_create(child, matches, NULL, parent, false);
427		if (rc) {
428			of_node_put(child);
429			break;
430		}
431	}
432
433	of_node_put(root);
434	return rc;
435}
436EXPORT_SYMBOL(of_platform_bus_probe);
437
438/**
439 * of_platform_populate() - Populate platform_devices from device tree data
440 * @root: parent of the first level to probe or NULL for the root of the tree
441 * @matches: match table, NULL to use the default
442 * @lookup: auxdata table for matching id and platform_data with device nodes
443 * @parent: parent to hook devices from, NULL for toplevel
444 *
445 * Similar to of_platform_bus_probe(), this function walks the device tree
446 * and creates devices from nodes.  It differs in that it follows the modern
447 * convention of requiring all device nodes to have a 'compatible' property,
448 * and it is suitable for creating devices which are children of the root
449 * node (of_platform_bus_probe will only create children of the root which
450 * are selected by the @matches argument).
451 *
452 * New board support should be using this function instead of
453 * of_platform_bus_probe().
454 *
455 * Return: 0 on success, < 0 on failure.
456 */
457int of_platform_populate(struct device_node *root,
458			const struct of_device_id *matches,
459			const struct of_dev_auxdata *lookup,
460			struct device *parent)
461{
462	struct device_node *child;
463	int rc = 0;
464
465	root = root ? of_node_get(root) : of_find_node_by_path("/");
466	if (!root)
467		return -EINVAL;
468
469	pr_debug("%s()\n", __func__);
470	pr_debug(" starting at: %pOF\n", root);
471
472	device_links_supplier_sync_state_pause();
473	for_each_child_of_node(root, child) {
474		rc = of_platform_bus_create(child, matches, lookup, parent, true);
475		if (rc) {
476			of_node_put(child);
477			break;
478		}
479	}
480	device_links_supplier_sync_state_resume();
481
482	of_node_set_flag(root, OF_POPULATED_BUS);
483
484	of_node_put(root);
485	return rc;
486}
487EXPORT_SYMBOL_GPL(of_platform_populate);
488
489int of_platform_default_populate(struct device_node *root,
490				 const struct of_dev_auxdata *lookup,
491				 struct device *parent)
492{
493	return of_platform_populate(root, of_default_bus_match_table, lookup,
494				    parent);
495}
496EXPORT_SYMBOL_GPL(of_platform_default_populate);
497
498static const struct of_device_id reserved_mem_matches[] = {
499	{ .compatible = "phram" },
500	{ .compatible = "qcom,rmtfs-mem" },
501	{ .compatible = "qcom,cmd-db" },
502	{ .compatible = "qcom,smem" },
503	{ .compatible = "ramoops" },
504	{ .compatible = "nvmem-rmem" },
505	{ .compatible = "google,open-dice" },
506	{}
507};
508
509static int __init of_platform_default_populate_init(void)
510{
511	struct device_node *node;
512
513	device_links_supplier_sync_state_pause();
514
515	if (IS_ENABLED(CONFIG_PPC)) {
516		struct device_node *boot_display = NULL;
517		struct platform_device *dev;
518		int display_number = 0;
519		int ret;
520
521		/* Check if we have a MacOS display without a node spec */
522		if (of_property_present(of_chosen, "linux,bootx-noscreen")) {
523			/*
524			 * The old code tried to work out which node was the MacOS
525			 * display based on the address. I'm dropping that since the
526			 * lack of a node spec only happens with old BootX versions
527			 * (users can update) and with this code, they'll still get
528			 * a display (just not the palette hacks).
529			 */
530			dev = platform_device_alloc("bootx-noscreen", 0);
531			if (WARN_ON(!dev))
532				return -ENOMEM;
533			ret = platform_device_add(dev);
534			if (WARN_ON(ret)) {
535				platform_device_put(dev);
536				return ret;
537			}
538		}
539
540		/*
541		 * For OF framebuffers, first create the device for the boot display,
542		 * then for the other framebuffers. Only fail for the boot display;
543		 * ignore errors for the rest.
544		 */
545		for_each_node_by_type(node, "display") {
546			if (!of_get_property(node, "linux,opened", NULL) ||
547			    !of_get_property(node, "linux,boot-display", NULL))
548				continue;
549			dev = of_platform_device_create(node, "of-display", NULL);
550			of_node_put(node);
551			if (WARN_ON(!dev))
552				return -ENOMEM;
553			boot_display = node;
554			display_number++;
555			break;
556		}
557		for_each_node_by_type(node, "display") {
558			char buf[14];
559			const char *of_display_format = "of-display.%d";
560
561			if (!of_get_property(node, "linux,opened", NULL) || node == boot_display)
562				continue;
563			ret = snprintf(buf, sizeof(buf), of_display_format, display_number++);
564			if (ret < sizeof(buf))
565				of_platform_device_create(node, buf, NULL);
566		}
567
568	} else {
569		/*
570		 * Handle certain compatibles explicitly, since we don't want to create
571		 * platform_devices for every node in /reserved-memory with a
572		 * "compatible",
573		 */
574		for_each_matching_node(node, reserved_mem_matches)
575			of_platform_device_create(node, NULL, NULL);
576
577		node = of_find_node_by_path("/firmware");
578		if (node) {
579			of_platform_populate(node, NULL, NULL, NULL);
580			of_node_put(node);
581		}
582
583		node = of_get_compatible_child(of_chosen, "simple-framebuffer");
584		if (node) {
585			/*
586			 * Since a "simple-framebuffer" device is already added
587			 * here, disable the Generic System Framebuffers (sysfb)
588			 * to prevent it from registering another device for the
589			 * system framebuffer later (e.g: using the screen_info
590			 * data that may had been filled as well).
591			 *
592			 * This can happen for example on DT systems that do EFI
593			 * booting and may provide a GOP handle to the EFI stub.
594			 */
595			sysfb_disable();
596			of_platform_device_create(node, NULL, NULL);
597			of_node_put(node);
598		}
599
600		/* Populate everything else. */
601		of_platform_default_populate(NULL, NULL, NULL);
602	}
603
604	return 0;
605}
606arch_initcall_sync(of_platform_default_populate_init);
607
608static int __init of_platform_sync_state_init(void)
609{
610	device_links_supplier_sync_state_resume();
611	return 0;
612}
613late_initcall_sync(of_platform_sync_state_init);
614
615int of_platform_device_destroy(struct device *dev, void *data)
616{
617	/* Do not touch devices not populated from the device tree */
618	if (!dev->of_node || !of_node_check_flag(dev->of_node, OF_POPULATED))
619		return 0;
620
621	/* Recurse for any nodes that were treated as busses */
622	if (of_node_check_flag(dev->of_node, OF_POPULATED_BUS))
623		device_for_each_child(dev, NULL, of_platform_device_destroy);
624
625	of_node_clear_flag(dev->of_node, OF_POPULATED);
626	of_node_clear_flag(dev->of_node, OF_POPULATED_BUS);
627
628	if (dev->bus == &platform_bus_type)
629		platform_device_unregister(to_platform_device(dev));
630#ifdef CONFIG_ARM_AMBA
631	else if (dev->bus == &amba_bustype)
632		amba_device_unregister(to_amba_device(dev));
633#endif
634
635	return 0;
636}
637EXPORT_SYMBOL_GPL(of_platform_device_destroy);
638
639/**
640 * of_platform_depopulate() - Remove devices populated from device tree
641 * @parent: device which children will be removed
642 *
643 * Complementary to of_platform_populate(), this function removes children
644 * of the given device (and, recursively, their children) that have been
645 * created from their respective device tree nodes (and only those,
646 * leaving others - eg. manually created - unharmed).
647 */
648void of_platform_depopulate(struct device *parent)
649{
650	if (parent->of_node && of_node_check_flag(parent->of_node, OF_POPULATED_BUS)) {
651		device_for_each_child_reverse(parent, NULL, of_platform_device_destroy);
652		of_node_clear_flag(parent->of_node, OF_POPULATED_BUS);
653	}
654}
655EXPORT_SYMBOL_GPL(of_platform_depopulate);
656
657static void devm_of_platform_populate_release(struct device *dev, void *res)
658{
659	of_platform_depopulate(*(struct device **)res);
660}
661
662/**
663 * devm_of_platform_populate() - Populate platform_devices from device tree data
664 * @dev: device that requested to populate from device tree data
665 *
666 * Similar to of_platform_populate(), but will automatically call
667 * of_platform_depopulate() when the device is unbound from the bus.
668 *
669 * Return: 0 on success, < 0 on failure.
670 */
671int devm_of_platform_populate(struct device *dev)
672{
673	struct device **ptr;
674	int ret;
675
676	if (!dev)
677		return -EINVAL;
678
679	ptr = devres_alloc(devm_of_platform_populate_release,
680			   sizeof(*ptr), GFP_KERNEL);
681	if (!ptr)
682		return -ENOMEM;
683
684	ret = of_platform_populate(dev->of_node, NULL, NULL, dev);
685	if (ret) {
686		devres_free(ptr);
687	} else {
688		*ptr = dev;
689		devres_add(dev, ptr);
690	}
691
692	return ret;
693}
694EXPORT_SYMBOL_GPL(devm_of_platform_populate);
695
696static int devm_of_platform_match(struct device *dev, void *res, void *data)
697{
698	struct device **ptr = res;
699
700	if (!ptr) {
701		WARN_ON(!ptr);
702		return 0;
703	}
704
705	return *ptr == data;
706}
707
708/**
709 * devm_of_platform_depopulate() - Remove devices populated from device tree
710 * @dev: device that requested to depopulate from device tree data
711 *
712 * Complementary to devm_of_platform_populate(), this function removes children
713 * of the given device (and, recursively, their children) that have been
714 * created from their respective device tree nodes (and only those,
715 * leaving others - eg. manually created - unharmed).
716 */
717void devm_of_platform_depopulate(struct device *dev)
718{
719	int ret;
720
721	ret = devres_release(dev, devm_of_platform_populate_release,
722			     devm_of_platform_match, dev);
723
724	WARN_ON(ret);
725}
726EXPORT_SYMBOL_GPL(devm_of_platform_depopulate);
727
728#ifdef CONFIG_OF_DYNAMIC
729static int of_platform_notify(struct notifier_block *nb,
730				unsigned long action, void *arg)
731{
732	struct of_reconfig_data *rd = arg;
733	struct platform_device *pdev_parent, *pdev;
734	bool children_left;
735
736	switch (of_reconfig_get_state_change(action, rd)) {
737	case OF_RECONFIG_CHANGE_ADD:
738		/* verify that the parent is a bus */
739		if (!of_node_check_flag(rd->dn->parent, OF_POPULATED_BUS))
740			return NOTIFY_OK;	/* not for us */
741
742		/* already populated? (driver using of_populate manually) */
743		if (of_node_check_flag(rd->dn, OF_POPULATED))
744			return NOTIFY_OK;
745
746		/*
747		 * Clear the flag before adding the device so that fw_devlink
748		 * doesn't skip adding consumers to this device.
749		 */
750		rd->dn->fwnode.flags &= ~FWNODE_FLAG_NOT_DEVICE;
751		/* pdev_parent may be NULL when no bus platform device */
752		pdev_parent = of_find_device_by_node(rd->dn->parent);
753		pdev = of_platform_device_create(rd->dn, NULL,
754				pdev_parent ? &pdev_parent->dev : NULL);
755		platform_device_put(pdev_parent);
756
757		if (pdev == NULL) {
758			pr_err("%s: failed to create for '%pOF'\n",
759					__func__, rd->dn);
760			/* of_platform_device_create tosses the error code */
761			return notifier_from_errno(-EINVAL);
762		}
763		break;
764
765	case OF_RECONFIG_CHANGE_REMOVE:
766
767		/* already depopulated? */
768		if (!of_node_check_flag(rd->dn, OF_POPULATED))
769			return NOTIFY_OK;
770
771		/* find our device by node */
772		pdev = of_find_device_by_node(rd->dn);
773		if (pdev == NULL)
774			return NOTIFY_OK;	/* no? not meant for us */
775
776		/* unregister takes one ref away */
777		of_platform_device_destroy(&pdev->dev, &children_left);
778
779		/* and put the reference of the find */
780		platform_device_put(pdev);
781		break;
782	}
783
784	return NOTIFY_OK;
785}
786
787static struct notifier_block platform_of_notifier = {
788	.notifier_call = of_platform_notify,
789};
790
791void of_platform_register_reconfig_notifier(void)
792{
793	WARN_ON(of_reconfig_notifier_register(&platform_of_notifier));
794}
795#endif /* CONFIG_OF_DYNAMIC */
796
797#endif /* CONFIG_OF_ADDRESS */