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
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.
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>
26 const struct of_device_id of_default_bus_match_table
[] = {
27 { .compatible
= "simple-bus", },
28 { .compatible
= "simple-mfd", },
29 #ifdef CONFIG_ARM_AMBA
30 { .compatible
= "arm,amba-bus", },
31 #endif /* CONFIG_ARM_AMBA */
32 {} /* Empty terminated list */
35 static int of_dev_node_match(struct device
*dev
, void *data
)
37 return dev
->of_node
== data
;
41 * of_find_device_by_node - Find the platform_device associated with a node
42 * @np: Pointer to device tree node
44 * Returns platform_device pointer, or NULL if not found
46 struct platform_device
*of_find_device_by_node(struct device_node
*np
)
50 dev
= bus_find_device(&platform_bus_type
, NULL
, np
, of_dev_node_match
);
51 return dev
? to_platform_device(dev
) : NULL
;
53 EXPORT_SYMBOL(of_find_device_by_node
);
55 #ifdef CONFIG_OF_ADDRESS
57 * The following routines scan a subtree and registers a device for
58 * each applicable node.
60 * Note: sparc doesn't use these routines because it has a different
61 * mechanism for creating devices from device tree nodes.
65 * of_device_make_bus_id - Use the device node data to assign a unique name
66 * @dev: pointer to device structure that is linked to a device tree node
68 * This routine will first try using the translated bus address to
69 * derive a unique name. If it cannot, then it will prepend names from
70 * parent nodes until a unique name can be derived.
72 void of_device_make_bus_id(struct device
*dev
)
74 struct device_node
*node
= dev
->of_node
;
78 /* Construct the name, using parent nodes if necessary to ensure uniqueness */
79 while (node
->parent
) {
81 * If the address can be translated, then that is as much
82 * uniqueness as we need. Make it the first component and return
84 reg
= of_get_property(node
, "reg", NULL
);
85 if (reg
&& (addr
= of_translate_address(node
, reg
)) != OF_BAD_ADDR
) {
86 dev_set_name(dev
, dev_name(dev
) ? "%llx.%s:%s" : "%llx.%s",
87 (unsigned long long)addr
, node
->name
,
92 /* format arguments only used if dev_name() resolves to NULL */
93 dev_set_name(dev
, dev_name(dev
) ? "%s:%s" : "%s",
94 strrchr(node
->full_name
, '/') + 1, dev_name(dev
));
100 * of_device_alloc - Allocate and initialize an of_device
101 * @np: device node to assign to device
102 * @bus_id: Name to assign to the device. May be null to use default name.
103 * @parent: Parent device.
105 struct platform_device
*of_device_alloc(struct device_node
*np
,
107 struct device
*parent
)
109 struct platform_device
*dev
;
110 int rc
, i
, num_reg
= 0, num_irq
;
111 struct resource
*res
, temp_res
;
113 dev
= platform_device_alloc("", -1);
117 /* count the io and irq resources */
118 while (of_address_to_resource(np
, num_reg
, &temp_res
) == 0)
120 num_irq
= of_irq_count(np
);
122 /* Populate the resource table */
123 if (num_irq
|| num_reg
) {
124 res
= kzalloc(sizeof(*res
) * (num_irq
+ num_reg
), GFP_KERNEL
);
126 platform_device_put(dev
);
130 dev
->num_resources
= num_reg
+ num_irq
;
132 for (i
= 0; i
< num_reg
; i
++, res
++) {
133 rc
= of_address_to_resource(np
, i
, res
);
136 if (of_irq_to_resource_table(np
, res
, num_irq
) != num_irq
)
137 pr_debug("not all legacy IRQ resources mapped for %s\n",
141 dev
->dev
.of_node
= of_node_get(np
);
142 dev
->dev
.parent
= parent
? : &platform_bus
;
145 dev_set_name(&dev
->dev
, "%s", bus_id
);
147 of_device_make_bus_id(&dev
->dev
);
151 EXPORT_SYMBOL(of_device_alloc
);
153 static void of_dma_deconfigure(struct device
*dev
)
155 arch_teardown_dma_ops(dev
);
159 * of_platform_device_create_pdata - Alloc, initialize and register an of_device
160 * @np: pointer to node to create device for
161 * @bus_id: name to assign device
162 * @platform_data: pointer to populate platform_data pointer with
163 * @parent: Linux device model parent device.
165 * Returns pointer to created platform device, or NULL if a device was not
166 * registered. Unavailable devices will not get registered.
168 static struct platform_device
*of_platform_device_create_pdata(
169 struct device_node
*np
,
172 struct device
*parent
)
174 struct platform_device
*dev
;
176 if (!of_device_is_available(np
) ||
177 of_node_test_and_set_flag(np
, OF_POPULATED
))
180 dev
= of_device_alloc(np
, bus_id
, parent
);
184 dev
->dev
.bus
= &platform_bus_type
;
185 dev
->dev
.platform_data
= platform_data
;
186 of_dma_configure(&dev
->dev
, dev
->dev
.of_node
);
187 of_msi_configure(&dev
->dev
, dev
->dev
.of_node
);
189 if (of_device_add(dev
) != 0) {
190 of_dma_deconfigure(&dev
->dev
);
191 platform_device_put(dev
);
198 of_node_clear_flag(np
, OF_POPULATED
);
203 * of_platform_device_create - Alloc, initialize and register an of_device
204 * @np: pointer to node to create device for
205 * @bus_id: name to assign device
206 * @parent: Linux device model parent device.
208 * Returns pointer to created platform device, or NULL if a device was not
209 * registered. Unavailable devices will not get registered.
211 struct platform_device
*of_platform_device_create(struct device_node
*np
,
213 struct device
*parent
)
215 return of_platform_device_create_pdata(np
, bus_id
, NULL
, parent
);
217 EXPORT_SYMBOL(of_platform_device_create
);
219 #ifdef CONFIG_ARM_AMBA
220 static struct amba_device
*of_amba_device_create(struct device_node
*node
,
223 struct device
*parent
)
225 struct amba_device
*dev
;
229 pr_debug("Creating amba device %s\n", node
->full_name
);
231 if (!of_device_is_available(node
) ||
232 of_node_test_and_set_flag(node
, OF_POPULATED
))
235 dev
= amba_device_alloc(NULL
, 0, 0);
237 pr_err("%s(): amba_device_alloc() failed for %s\n",
238 __func__
, node
->full_name
);
242 /* setup generic device info */
243 dev
->dev
.of_node
= of_node_get(node
);
244 dev
->dev
.parent
= parent
? : &platform_bus
;
245 dev
->dev
.platform_data
= platform_data
;
247 dev_set_name(&dev
->dev
, "%s", bus_id
);
249 of_device_make_bus_id(&dev
->dev
);
250 of_dma_configure(&dev
->dev
, dev
->dev
.of_node
);
252 /* Allow the HW Peripheral ID to be overridden */
253 prop
= of_get_property(node
, "arm,primecell-periphid", NULL
);
255 dev
->periphid
= of_read_ulong(prop
, 1);
257 /* Decode the IRQs and address ranges */
258 for (i
= 0; i
< AMBA_NR_IRQS
; i
++)
259 dev
->irq
[i
] = irq_of_parse_and_map(node
, i
);
261 ret
= of_address_to_resource(node
, 0, &dev
->res
);
263 pr_err("%s(): of_address_to_resource() failed (%d) for %s\n",
264 __func__
, ret
, node
->full_name
);
268 ret
= amba_device_add(dev
, &iomem_resource
);
270 pr_err("%s(): amba_device_add() failed (%d) for %s\n",
271 __func__
, ret
, node
->full_name
);
278 amba_device_put(dev
);
280 of_node_clear_flag(node
, OF_POPULATED
);
283 #else /* CONFIG_ARM_AMBA */
284 static struct amba_device
*of_amba_device_create(struct device_node
*node
,
287 struct device
*parent
)
291 #endif /* CONFIG_ARM_AMBA */
294 * of_devname_lookup() - Given a device node, lookup the preferred Linux name
296 static const struct of_dev_auxdata
*of_dev_lookup(const struct of_dev_auxdata
*lookup
,
297 struct device_node
*np
)
304 for(; lookup
->compatible
!= NULL
; lookup
++) {
305 if (!of_device_is_compatible(np
, lookup
->compatible
))
307 if (!of_address_to_resource(np
, 0, &res
))
308 if (res
.start
!= lookup
->phys_addr
)
310 pr_debug("%s: devname=%s\n", np
->full_name
, lookup
->name
);
318 * of_platform_bus_create() - Create a device for a node and its children.
319 * @bus: device node of the bus to instantiate
320 * @matches: match table for bus nodes
321 * @lookup: auxdata table for matching id and platform_data with device nodes
322 * @parent: parent for new device, or NULL for top level.
323 * @strict: require compatible property
325 * Creates a platform_device for the provided device_node, and optionally
326 * recursively create devices for all the child nodes.
328 static int of_platform_bus_create(struct device_node
*bus
,
329 const struct of_device_id
*matches
,
330 const struct of_dev_auxdata
*lookup
,
331 struct device
*parent
, bool strict
)
333 const struct of_dev_auxdata
*auxdata
;
334 struct device_node
*child
;
335 struct platform_device
*dev
;
336 const char *bus_id
= NULL
;
337 void *platform_data
= NULL
;
340 /* Make sure it has a compatible property */
341 if (strict
&& (!of_get_property(bus
, "compatible", NULL
))) {
342 pr_debug("%s() - skipping %s, no compatible prop\n",
343 __func__
, bus
->full_name
);
347 auxdata
= of_dev_lookup(lookup
, bus
);
349 bus_id
= auxdata
->name
;
350 platform_data
= auxdata
->platform_data
;
353 if (of_device_is_compatible(bus
, "arm,primecell")) {
355 * Don't return an error here to keep compatibility with older
358 of_amba_device_create(bus
, bus_id
, platform_data
, parent
);
362 dev
= of_platform_device_create_pdata(bus
, bus_id
, platform_data
, parent
);
363 if (!dev
|| !of_match_node(matches
, bus
))
366 for_each_child_of_node(bus
, child
) {
367 pr_debug(" create child: %s\n", child
->full_name
);
368 rc
= of_platform_bus_create(child
, matches
, lookup
, &dev
->dev
, strict
);
374 of_node_set_flag(bus
, OF_POPULATED_BUS
);
379 * of_platform_bus_probe() - Probe the device-tree for platform buses
380 * @root: parent of the first level to probe or NULL for the root of the tree
381 * @matches: match table for bus nodes
382 * @parent: parent to hook devices from, NULL for toplevel
384 * Note that children of the provided root are not instantiated as devices
385 * unless the specified root itself matches the bus list and is not NULL.
387 int of_platform_bus_probe(struct device_node
*root
,
388 const struct of_device_id
*matches
,
389 struct device
*parent
)
391 struct device_node
*child
;
394 root
= root
? of_node_get(root
) : of_find_node_by_path("/");
398 pr_debug("of_platform_bus_probe()\n");
399 pr_debug(" starting at: %s\n", root
->full_name
);
401 /* Do a self check of bus type, if there's a match, create children */
402 if (of_match_node(matches
, root
)) {
403 rc
= of_platform_bus_create(root
, matches
, NULL
, parent
, false);
404 } else for_each_child_of_node(root
, child
) {
405 if (!of_match_node(matches
, child
))
407 rc
= of_platform_bus_create(child
, matches
, NULL
, parent
, false);
417 EXPORT_SYMBOL(of_platform_bus_probe
);
420 * of_platform_populate() - Populate platform_devices from device tree data
421 * @root: parent of the first level to probe or NULL for the root of the tree
422 * @matches: match table, NULL to use the default
423 * @lookup: auxdata table for matching id and platform_data with device nodes
424 * @parent: parent to hook devices from, NULL for toplevel
426 * Similar to of_platform_bus_probe(), this function walks the device tree
427 * and creates devices from nodes. It differs in that it follows the modern
428 * convention of requiring all device nodes to have a 'compatible' property,
429 * and it is suitable for creating devices which are children of the root
430 * node (of_platform_bus_probe will only create children of the root which
431 * are selected by the @matches argument).
433 * New board support should be using this function instead of
434 * of_platform_bus_probe().
436 * Returns 0 on success, < 0 on failure.
438 int of_platform_populate(struct device_node
*root
,
439 const struct of_device_id
*matches
,
440 const struct of_dev_auxdata
*lookup
,
441 struct device
*parent
)
443 struct device_node
*child
;
446 root
= root
? of_node_get(root
) : of_find_node_by_path("/");
450 for_each_child_of_node(root
, child
) {
451 rc
= of_platform_bus_create(child
, matches
, lookup
, parent
, true);
457 of_node_set_flag(root
, OF_POPULATED_BUS
);
462 EXPORT_SYMBOL_GPL(of_platform_populate
);
464 int of_platform_default_populate(struct device_node
*root
,
465 const struct of_dev_auxdata
*lookup
,
466 struct device
*parent
)
468 return of_platform_populate(root
, of_default_bus_match_table
, lookup
,
471 EXPORT_SYMBOL_GPL(of_platform_default_populate
);
473 static int of_platform_device_destroy(struct device
*dev
, void *data
)
475 /* Do not touch devices not populated from the device tree */
476 if (!dev
->of_node
|| !of_node_check_flag(dev
->of_node
, OF_POPULATED
))
479 /* Recurse for any nodes that were treated as busses */
480 if (of_node_check_flag(dev
->of_node
, OF_POPULATED_BUS
))
481 device_for_each_child(dev
, NULL
, of_platform_device_destroy
);
483 if (dev
->bus
== &platform_bus_type
)
484 platform_device_unregister(to_platform_device(dev
));
485 #ifdef CONFIG_ARM_AMBA
486 else if (dev
->bus
== &amba_bustype
)
487 amba_device_unregister(to_amba_device(dev
));
490 of_dma_deconfigure(dev
);
491 of_node_clear_flag(dev
->of_node
, OF_POPULATED
);
492 of_node_clear_flag(dev
->of_node
, OF_POPULATED_BUS
);
497 * of_platform_depopulate() - Remove devices populated from device tree
498 * @parent: device which children will be removed
500 * Complementary to of_platform_populate(), this function removes children
501 * of the given device (and, recurrently, their children) that have been
502 * created from their respective device tree nodes (and only those,
503 * leaving others - eg. manually created - unharmed).
505 * Returns 0 when all children devices have been removed or
506 * -EBUSY when some children remained.
508 void of_platform_depopulate(struct device
*parent
)
510 if (parent
->of_node
&& of_node_check_flag(parent
->of_node
, OF_POPULATED_BUS
)) {
511 device_for_each_child(parent
, NULL
, of_platform_device_destroy
);
512 of_node_clear_flag(parent
->of_node
, OF_POPULATED_BUS
);
515 EXPORT_SYMBOL_GPL(of_platform_depopulate
);
517 #ifdef CONFIG_OF_DYNAMIC
518 static int of_platform_notify(struct notifier_block
*nb
,
519 unsigned long action
, void *arg
)
521 struct of_reconfig_data
*rd
= arg
;
522 struct platform_device
*pdev_parent
, *pdev
;
525 switch (of_reconfig_get_state_change(action
, rd
)) {
526 case OF_RECONFIG_CHANGE_ADD
:
527 /* verify that the parent is a bus */
528 if (!of_node_check_flag(rd
->dn
->parent
, OF_POPULATED_BUS
))
529 return NOTIFY_OK
; /* not for us */
531 /* already populated? (driver using of_populate manually) */
532 if (of_node_check_flag(rd
->dn
, OF_POPULATED
))
535 /* pdev_parent may be NULL when no bus platform device */
536 pdev_parent
= of_find_device_by_node(rd
->dn
->parent
);
537 pdev
= of_platform_device_create(rd
->dn
, NULL
,
538 pdev_parent
? &pdev_parent
->dev
: NULL
);
539 of_dev_put(pdev_parent
);
542 pr_err("%s: failed to create for '%s'\n",
543 __func__
, rd
->dn
->full_name
);
544 /* of_platform_device_create tosses the error code */
545 return notifier_from_errno(-EINVAL
);
549 case OF_RECONFIG_CHANGE_REMOVE
:
551 /* already depopulated? */
552 if (!of_node_check_flag(rd
->dn
, OF_POPULATED
))
555 /* find our device by node */
556 pdev
= of_find_device_by_node(rd
->dn
);
558 return NOTIFY_OK
; /* no? not meant for us */
560 /* unregister takes one ref away */
561 of_platform_device_destroy(&pdev
->dev
, &children_left
);
563 /* and put the reference of the find */
571 static struct notifier_block platform_of_notifier
= {
572 .notifier_call
= of_platform_notify
,
575 void of_platform_register_reconfig_notifier(void)
577 WARN_ON(of_reconfig_notifier_register(&platform_of_notifier
));
579 #endif /* CONFIG_OF_DYNAMIC */
581 #endif /* CONFIG_OF_ADDRESS */