1 // SPDX-License-Identifier: GPL-2.0+
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
10 #define pr_fmt(fmt) "OF: " fmt
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>
25 const 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 */
35 static const struct of_device_id of_skipped_node_table
[] = {
36 { .compatible
= "operating-points-v2", },
37 {} /* Empty terminated list */
41 * of_find_device_by_node - Find the platform_device associated with a node
42 * @np: Pointer to device tree node
44 * Takes a reference to the embedded struct device which needs to be dropped
47 * Returns platform_device pointer, or NULL if not found
49 struct platform_device
*of_find_device_by_node(struct device_node
*np
)
53 dev
= bus_find_device_by_of_node(&platform_bus_type
, np
);
54 return dev
? to_platform_device(dev
) : NULL
;
56 EXPORT_SYMBOL(of_find_device_by_node
);
58 #ifdef CONFIG_OF_ADDRESS
60 * The following routines scan a subtree and registers a device for
61 * each applicable node.
63 * Note: sparc doesn't use these routines because it has a different
64 * mechanism for creating devices from device tree nodes.
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
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.
75 static void of_device_make_bus_id(struct device
*dev
)
77 struct device_node
*node
= dev
->of_node
;
81 /* Construct the name, using parent nodes if necessary to ensure uniqueness */
82 while (node
->parent
) {
84 * If the address can be translated, then that is as much
85 * uniqueness as we need. Make it the first component and return
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.%pOFn:%s" : "%llx.%pOFn",
90 addr
, node
, dev_name(dev
));
94 /* format arguments only used if dev_name() resolves to NULL */
95 dev_set_name(dev
, dev_name(dev
) ? "%s:%s" : "%s",
96 kbasename(node
->full_name
), dev_name(dev
));
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.
107 struct platform_device
*of_device_alloc(struct device_node
*np
,
109 struct device
*parent
)
111 struct platform_device
*dev
;
112 int rc
, i
, num_reg
= 0, num_irq
;
113 struct resource
*res
, temp_res
;
115 dev
= platform_device_alloc("", PLATFORM_DEVID_NONE
);
119 /* count the io and irq resources */
120 while (of_address_to_resource(np
, num_reg
, &temp_res
) == 0)
122 num_irq
= of_irq_count(np
);
124 /* Populate the resource table */
125 if (num_irq
|| num_reg
) {
126 res
= kcalloc(num_irq
+ num_reg
, sizeof(*res
), GFP_KERNEL
);
128 platform_device_put(dev
);
132 dev
->num_resources
= num_reg
+ num_irq
;
134 for (i
= 0; i
< num_reg
; i
++, res
++) {
135 rc
= of_address_to_resource(np
, i
, res
);
138 if (of_irq_to_resource_table(np
, res
, num_irq
) != num_irq
)
139 pr_debug("not all legacy IRQ resources mapped for %pOFn\n",
143 dev
->dev
.of_node
= of_node_get(np
);
144 dev
->dev
.fwnode
= &np
->fwnode
;
145 dev
->dev
.parent
= parent
? : &platform_bus
;
148 dev_set_name(&dev
->dev
, "%s", bus_id
);
150 of_device_make_bus_id(&dev
->dev
);
154 EXPORT_SYMBOL(of_device_alloc
);
157 * of_platform_device_create_pdata - Alloc, initialize and register an of_device
158 * @np: pointer to node to create device for
159 * @bus_id: name to assign device
160 * @platform_data: pointer to populate platform_data pointer with
161 * @parent: Linux device model parent device.
163 * Returns pointer to created platform device, or NULL if a device was not
164 * registered. Unavailable devices will not get registered.
166 static struct platform_device
*of_platform_device_create_pdata(
167 struct device_node
*np
,
170 struct device
*parent
)
172 struct platform_device
*dev
;
174 if (!of_device_is_available(np
) ||
175 of_node_test_and_set_flag(np
, OF_POPULATED
))
178 dev
= of_device_alloc(np
, bus_id
, parent
);
182 dev
->dev
.coherent_dma_mask
= DMA_BIT_MASK(32);
183 if (!dev
->dev
.dma_mask
)
184 dev
->dev
.dma_mask
= &dev
->dev
.coherent_dma_mask
;
185 dev
->dev
.bus
= &platform_bus_type
;
186 dev
->dev
.platform_data
= platform_data
;
187 of_msi_configure(&dev
->dev
, dev
->dev
.of_node
);
189 if (of_device_add(dev
) != 0) {
190 platform_device_put(dev
);
197 of_node_clear_flag(np
, OF_POPULATED
);
202 * of_platform_device_create - Alloc, initialize and register an of_device
203 * @np: pointer to node to create device for
204 * @bus_id: name to assign device
205 * @parent: Linux device model parent device.
207 * Returns pointer to created platform device, or NULL if a device was not
208 * registered. Unavailable devices will not get registered.
210 struct platform_device
*of_platform_device_create(struct device_node
*np
,
212 struct device
*parent
)
214 return of_platform_device_create_pdata(np
, bus_id
, NULL
, parent
);
216 EXPORT_SYMBOL(of_platform_device_create
);
218 #ifdef CONFIG_ARM_AMBA
219 static struct amba_device
*of_amba_device_create(struct device_node
*node
,
222 struct device
*parent
)
224 struct amba_device
*dev
;
228 pr_debug("Creating amba device %pOF\n", node
);
230 if (!of_device_is_available(node
) ||
231 of_node_test_and_set_flag(node
, OF_POPULATED
))
234 dev
= amba_device_alloc(NULL
, 0, 0);
238 /* AMBA devices only support a single DMA mask */
239 dev
->dev
.coherent_dma_mask
= DMA_BIT_MASK(32);
240 dev
->dev
.dma_mask
= &dev
->dev
.coherent_dma_mask
;
242 /* setup generic device info */
243 dev
->dev
.of_node
= of_node_get(node
);
244 dev
->dev
.fwnode
= &node
->fwnode
;
245 dev
->dev
.parent
= parent
? : &platform_bus
;
246 dev
->dev
.platform_data
= platform_data
;
248 dev_set_name(&dev
->dev
, "%s", bus_id
);
250 of_device_make_bus_id(&dev
->dev
);
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("amba: of_address_to_resource() failed (%d) for %pOF\n",
268 ret
= amba_device_add(dev
, &iomem_resource
);
270 pr_err("amba_device_add() failed (%d) for %pOF\n",
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
)
299 const struct of_dev_auxdata
*auxdata
;
307 for (; auxdata
->compatible
; auxdata
++) {
308 if (!of_device_is_compatible(np
, auxdata
->compatible
))
311 if (!of_address_to_resource(np
, 0, &res
))
312 if (res
.start
!= auxdata
->phys_addr
)
314 pr_debug("%pOF: devname=%s\n", np
, auxdata
->name
);
321 /* Try compatible match if no phys_addr and name are specified */
323 for (; auxdata
->compatible
; auxdata
++) {
324 if (!of_device_is_compatible(np
, auxdata
->compatible
))
326 if (!auxdata
->phys_addr
&& !auxdata
->name
) {
327 pr_debug("%pOF: compatible match\n", np
);
336 * of_platform_bus_create() - Create a device for a node and its children.
337 * @bus: device node of the bus to instantiate
338 * @matches: match table for bus nodes
339 * @lookup: auxdata table for matching id and platform_data with device nodes
340 * @parent: parent for new device, or NULL for top level.
341 * @strict: require compatible property
343 * Creates a platform_device for the provided device_node, and optionally
344 * recursively create devices for all the child nodes.
346 static int of_platform_bus_create(struct device_node
*bus
,
347 const struct of_device_id
*matches
,
348 const struct of_dev_auxdata
*lookup
,
349 struct device
*parent
, bool strict
)
351 const struct of_dev_auxdata
*auxdata
;
352 struct device_node
*child
;
353 struct platform_device
*dev
;
354 const char *bus_id
= NULL
;
355 void *platform_data
= NULL
;
358 /* Make sure it has a compatible property */
359 if (strict
&& (!of_get_property(bus
, "compatible", NULL
))) {
360 pr_debug("%s() - skipping %pOF, no compatible prop\n",
365 /* Skip nodes for which we don't want to create devices */
366 if (unlikely(of_match_node(of_skipped_node_table
, bus
))) {
367 pr_debug("%s() - skipping %pOF node\n", __func__
, bus
);
371 if (of_node_check_flag(bus
, OF_POPULATED_BUS
)) {
372 pr_debug("%s() - skipping %pOF, already populated\n",
377 auxdata
= of_dev_lookup(lookup
, bus
);
379 bus_id
= auxdata
->name
;
380 platform_data
= auxdata
->platform_data
;
383 if (of_device_is_compatible(bus
, "arm,primecell")) {
385 * Don't return an error here to keep compatibility with older
388 of_amba_device_create(bus
, bus_id
, platform_data
, parent
);
392 dev
= of_platform_device_create_pdata(bus
, bus_id
, platform_data
, parent
);
393 if (!dev
|| !of_match_node(matches
, bus
))
396 for_each_child_of_node(bus
, child
) {
397 pr_debug(" create child: %pOF\n", child
);
398 rc
= of_platform_bus_create(child
, matches
, lookup
, &dev
->dev
, strict
);
404 of_node_set_flag(bus
, OF_POPULATED_BUS
);
409 * of_platform_bus_probe() - Probe the device-tree for platform buses
410 * @root: parent of the first level to probe or NULL for the root of the tree
411 * @matches: match table for bus nodes
412 * @parent: parent to hook devices from, NULL for toplevel
414 * Note that children of the provided root are not instantiated as devices
415 * unless the specified root itself matches the bus list and is not NULL.
417 int of_platform_bus_probe(struct device_node
*root
,
418 const struct of_device_id
*matches
,
419 struct device
*parent
)
421 struct device_node
*child
;
424 root
= root
? of_node_get(root
) : of_find_node_by_path("/");
428 pr_debug("%s()\n", __func__
);
429 pr_debug(" starting at: %pOF\n", root
);
431 /* Do a self check of bus type, if there's a match, create children */
432 if (of_match_node(matches
, root
)) {
433 rc
= of_platform_bus_create(root
, matches
, NULL
, parent
, false);
434 } else for_each_child_of_node(root
, child
) {
435 if (!of_match_node(matches
, child
))
437 rc
= of_platform_bus_create(child
, matches
, NULL
, parent
, false);
447 EXPORT_SYMBOL(of_platform_bus_probe
);
450 * of_platform_populate() - Populate platform_devices from device tree data
451 * @root: parent of the first level to probe or NULL for the root of the tree
452 * @matches: match table, NULL to use the default
453 * @lookup: auxdata table for matching id and platform_data with device nodes
454 * @parent: parent to hook devices from, NULL for toplevel
456 * Similar to of_platform_bus_probe(), this function walks the device tree
457 * and creates devices from nodes. It differs in that it follows the modern
458 * convention of requiring all device nodes to have a 'compatible' property,
459 * and it is suitable for creating devices which are children of the root
460 * node (of_platform_bus_probe will only create children of the root which
461 * are selected by the @matches argument).
463 * New board support should be using this function instead of
464 * of_platform_bus_probe().
466 * Returns 0 on success, < 0 on failure.
468 int of_platform_populate(struct device_node
*root
,
469 const struct of_device_id
*matches
,
470 const struct of_dev_auxdata
*lookup
,
471 struct device
*parent
)
473 struct device_node
*child
;
476 root
= root
? of_node_get(root
) : of_find_node_by_path("/");
480 pr_debug("%s()\n", __func__
);
481 pr_debug(" starting at: %pOF\n", root
);
483 for_each_child_of_node(root
, child
) {
484 rc
= of_platform_bus_create(child
, matches
, lookup
, parent
, true);
490 of_node_set_flag(root
, OF_POPULATED_BUS
);
495 EXPORT_SYMBOL_GPL(of_platform_populate
);
497 int of_platform_default_populate(struct device_node
*root
,
498 const struct of_dev_auxdata
*lookup
,
499 struct device
*parent
)
501 return of_platform_populate(root
, of_default_bus_match_table
, lookup
,
504 EXPORT_SYMBOL_GPL(of_platform_default_populate
);
507 static const struct of_device_id reserved_mem_matches
[] = {
508 { .compatible
= "qcom,rmtfs-mem" },
509 { .compatible
= "qcom,cmd-db" },
510 { .compatible
= "ramoops" },
514 static int __init
of_platform_default_populate_init(void)
516 struct device_node
*node
;
518 if (!of_have_populated_dt())
522 * Handle certain compatibles explicitly, since we don't want to create
523 * platform_devices for every node in /reserved-memory with a
526 for_each_matching_node(node
, reserved_mem_matches
)
527 of_platform_device_create(node
, NULL
, NULL
);
529 node
= of_find_node_by_path("/firmware");
531 of_platform_populate(node
, NULL
, NULL
, NULL
);
535 /* Populate everything else. */
536 of_platform_default_populate(NULL
, NULL
, NULL
);
540 arch_initcall_sync(of_platform_default_populate_init
);
543 int of_platform_device_destroy(struct device
*dev
, void *data
)
545 /* Do not touch devices not populated from the device tree */
546 if (!dev
->of_node
|| !of_node_check_flag(dev
->of_node
, OF_POPULATED
))
549 /* Recurse for any nodes that were treated as busses */
550 if (of_node_check_flag(dev
->of_node
, OF_POPULATED_BUS
))
551 device_for_each_child(dev
, NULL
, of_platform_device_destroy
);
553 of_node_clear_flag(dev
->of_node
, OF_POPULATED
);
554 of_node_clear_flag(dev
->of_node
, OF_POPULATED_BUS
);
556 if (dev
->bus
== &platform_bus_type
)
557 platform_device_unregister(to_platform_device(dev
));
558 #ifdef CONFIG_ARM_AMBA
559 else if (dev
->bus
== &amba_bustype
)
560 amba_device_unregister(to_amba_device(dev
));
565 EXPORT_SYMBOL_GPL(of_platform_device_destroy
);
568 * of_platform_depopulate() - Remove devices populated from device tree
569 * @parent: device which children will be removed
571 * Complementary to of_platform_populate(), this function removes children
572 * of the given device (and, recurrently, their children) that have been
573 * created from their respective device tree nodes (and only those,
574 * leaving others - eg. manually created - unharmed).
576 void of_platform_depopulate(struct device
*parent
)
578 if (parent
->of_node
&& of_node_check_flag(parent
->of_node
, OF_POPULATED_BUS
)) {
579 device_for_each_child(parent
, NULL
, of_platform_device_destroy
);
580 of_node_clear_flag(parent
->of_node
, OF_POPULATED_BUS
);
583 EXPORT_SYMBOL_GPL(of_platform_depopulate
);
585 static void devm_of_platform_populate_release(struct device
*dev
, void *res
)
587 of_platform_depopulate(*(struct device
**)res
);
591 * devm_of_platform_populate() - Populate platform_devices from device tree data
592 * @dev: device that requested to populate from device tree data
594 * Similar to of_platform_populate(), but will automatically call
595 * of_platform_depopulate() when the device is unbound from the bus.
597 * Returns 0 on success, < 0 on failure.
599 int devm_of_platform_populate(struct device
*dev
)
607 ptr
= devres_alloc(devm_of_platform_populate_release
,
608 sizeof(*ptr
), GFP_KERNEL
);
612 ret
= of_platform_populate(dev
->of_node
, NULL
, NULL
, dev
);
617 devres_add(dev
, ptr
);
622 EXPORT_SYMBOL_GPL(devm_of_platform_populate
);
624 static int devm_of_platform_match(struct device
*dev
, void *res
, void *data
)
626 struct device
**ptr
= res
;
637 * devm_of_platform_depopulate() - Remove devices populated from device tree
638 * @dev: device that requested to depopulate from device tree data
640 * Complementary to devm_of_platform_populate(), this function removes children
641 * of the given device (and, recurrently, their children) that have been
642 * created from their respective device tree nodes (and only those,
643 * leaving others - eg. manually created - unharmed).
645 void devm_of_platform_depopulate(struct device
*dev
)
649 ret
= devres_release(dev
, devm_of_platform_populate_release
,
650 devm_of_platform_match
, dev
);
654 EXPORT_SYMBOL_GPL(devm_of_platform_depopulate
);
656 #ifdef CONFIG_OF_DYNAMIC
657 static int of_platform_notify(struct notifier_block
*nb
,
658 unsigned long action
, void *arg
)
660 struct of_reconfig_data
*rd
= arg
;
661 struct platform_device
*pdev_parent
, *pdev
;
664 switch (of_reconfig_get_state_change(action
, rd
)) {
665 case OF_RECONFIG_CHANGE_ADD
:
666 /* verify that the parent is a bus */
667 if (!of_node_check_flag(rd
->dn
->parent
, OF_POPULATED_BUS
))
668 return NOTIFY_OK
; /* not for us */
670 /* already populated? (driver using of_populate manually) */
671 if (of_node_check_flag(rd
->dn
, OF_POPULATED
))
674 /* pdev_parent may be NULL when no bus platform device */
675 pdev_parent
= of_find_device_by_node(rd
->dn
->parent
);
676 pdev
= of_platform_device_create(rd
->dn
, NULL
,
677 pdev_parent
? &pdev_parent
->dev
: NULL
);
678 of_dev_put(pdev_parent
);
681 pr_err("%s: failed to create for '%pOF'\n",
683 /* of_platform_device_create tosses the error code */
684 return notifier_from_errno(-EINVAL
);
688 case OF_RECONFIG_CHANGE_REMOVE
:
690 /* already depopulated? */
691 if (!of_node_check_flag(rd
->dn
, OF_POPULATED
))
694 /* find our device by node */
695 pdev
= of_find_device_by_node(rd
->dn
);
697 return NOTIFY_OK
; /* no? not meant for us */
699 /* unregister takes one ref away */
700 of_platform_device_destroy(&pdev
->dev
, &children_left
);
702 /* and put the reference of the find */
710 static struct notifier_block platform_of_notifier
= {
711 .notifier_call
= of_platform_notify
,
714 void of_platform_register_reconfig_notifier(void)
716 WARN_ON(of_reconfig_notifier_register(&platform_of_notifier
));
718 #endif /* CONFIG_OF_DYNAMIC */
720 #endif /* CONFIG_OF_ADDRESS */