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_irq.h>
21 #include <linux/of_platform.h>
22 #include <linux/platform_device.h>
23 #include <linux/sysfb.h>
25 #include "of_private.h"
27 const 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 */
38 * of_find_device_by_node - Find the platform_device associated with a node
39 * @np: Pointer to device tree node
41 * Takes a reference to the embedded struct device which needs to be dropped
44 * Return: 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_by_of_node(&platform_bus_type
, np
);
51 return dev
? to_platform_device(dev
) : NULL
;
53 EXPORT_SYMBOL(of_find_device_by_node
);
55 int of_device_add(struct platform_device
*ofdev
)
57 BUG_ON(ofdev
->dev
.of_node
== NULL
);
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
;
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.
69 set_dev_node(&ofdev
->dev
, of_node_to_nid(ofdev
->dev
.of_node
));
71 return device_add(&ofdev
->dev
);
74 int of_device_register(struct platform_device
*pdev
)
76 device_initialize(&pdev
->dev
);
77 return of_device_add(pdev
);
79 EXPORT_SYMBOL(of_device_register
);
81 void of_device_unregister(struct platform_device
*ofdev
)
83 device_unregister(&ofdev
->dev
);
85 EXPORT_SYMBOL(of_device_unregister
);
87 #ifdef CONFIG_OF_ADDRESS
88 static const struct of_device_id of_skipped_node_table
[] = {
89 { .compatible
= "operating-points-v2", },
90 {} /* Empty terminated list */
94 * The following routines scan a subtree and registers a device for
95 * each applicable node.
97 * Note: sparc doesn't use these routines because it has a different
98 * mechanism for creating devices from device tree nodes.
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;
113 struct resource
*res
;
115 dev
= platform_device_alloc("", PLATFORM_DEVID_NONE
);
119 /* count the io resources */
120 num_reg
= of_address_count(np
);
122 /* Populate the resource table */
124 res
= kcalloc(num_reg
, sizeof(*res
), GFP_KERNEL
);
126 platform_device_put(dev
);
130 dev
->num_resources
= num_reg
;
132 for (i
= 0; i
< num_reg
; i
++, res
++) {
133 rc
= of_address_to_resource(np
, i
, res
);
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
;
143 dev_set_name(&dev
->dev
, "%s", bus_id
);
145 of_device_make_bus_id(&dev
->dev
);
149 EXPORT_SYMBOL(of_device_alloc
);
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.
158 * Return: Pointer to created platform device, or NULL if a device was not
159 * registered. Unavailable devices will not get registered.
161 static struct platform_device
*of_platform_device_create_pdata(
162 struct device_node
*np
,
165 struct device
*parent
)
167 struct platform_device
*dev
;
169 pr_debug("create platform device: %pOF\n", np
);
171 if (!of_device_is_available(np
) ||
172 of_node_test_and_set_flag(np
, OF_POPULATED
))
175 dev
= of_device_alloc(np
, bus_id
, parent
);
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
);
186 if (of_device_add(dev
) != 0) {
187 platform_device_put(dev
);
194 of_node_clear_flag(np
, OF_POPULATED
);
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.
204 * Return: Pointer to created platform device, or NULL if a device was not
205 * registered. Unavailable devices will not get registered.
207 struct platform_device
*of_platform_device_create(struct device_node
*np
,
209 struct device
*parent
)
211 return of_platform_device_create_pdata(np
, bus_id
, NULL
, parent
);
213 EXPORT_SYMBOL(of_platform_device_create
);
215 #ifdef CONFIG_ARM_AMBA
216 static struct amba_device
*of_amba_device_create(struct device_node
*node
,
219 struct device
*parent
)
221 struct amba_device
*dev
;
224 pr_debug("Creating amba device %pOF\n", node
);
226 if (!of_device_is_available(node
) ||
227 of_node_test_and_set_flag(node
, OF_POPULATED
))
230 dev
= amba_device_alloc(NULL
, 0, 0);
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
;
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
;
243 dev_set_name(&dev
->dev
, "%s", bus_id
);
245 of_device_make_bus_id(&dev
->dev
);
247 /* Allow the HW Peripheral ID to be overridden */
248 of_property_read_u32(node
, "arm,primecell-periphid", &dev
->periphid
);
250 ret
= of_address_to_resource(node
, 0, &dev
->res
);
252 pr_err("amba: of_address_to_resource() failed (%d) for %pOF\n",
257 ret
= amba_device_add(dev
, &iomem_resource
);
259 pr_err("amba_device_add() failed (%d) for %pOF\n",
267 amba_device_put(dev
);
269 of_node_clear_flag(node
, OF_POPULATED
);
272 #else /* CONFIG_ARM_AMBA */
273 static struct amba_device
*of_amba_device_create(struct device_node
*node
,
276 struct device
*parent
)
280 #endif /* CONFIG_ARM_AMBA */
283 * of_dev_lookup() - Given a device node, lookup the preferred Linux name
285 static const struct of_dev_auxdata
*of_dev_lookup(const struct of_dev_auxdata
*lookup
,
286 struct device_node
*np
)
288 const struct of_dev_auxdata
*auxdata
;
296 for (; auxdata
->compatible
; auxdata
++) {
297 if (!of_device_is_compatible(np
, auxdata
->compatible
))
300 if (!of_address_to_resource(np
, 0, &res
))
301 if (res
.start
!= auxdata
->phys_addr
)
303 pr_debug("%pOF: devname=%s\n", np
, auxdata
->name
);
310 /* Try compatible match if no phys_addr and name are specified */
312 for (; auxdata
->compatible
; auxdata
++) {
313 if (!of_device_is_compatible(np
, auxdata
->compatible
))
315 if (!auxdata
->phys_addr
&& !auxdata
->name
) {
316 pr_debug("%pOF: compatible match\n", np
);
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
332 * Creates a platform_device for the provided device_node, and optionally
333 * recursively create devices for all the child nodes.
335 static 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
)
340 const struct of_dev_auxdata
*auxdata
;
341 struct platform_device
*dev
;
342 const char *bus_id
= NULL
;
343 void *platform_data
= NULL
;
346 /* Make sure it has a compatible property */
347 if (strict
&& (!of_get_property(bus
, "compatible", NULL
))) {
348 pr_debug("%s() - skipping %pOF, no compatible prop\n",
353 /* Skip nodes for which we don't want to create devices */
354 if (unlikely(of_match_node(of_skipped_node_table
, bus
))) {
355 pr_debug("%s() - skipping %pOF node\n", __func__
, bus
);
359 if (of_node_check_flag(bus
, OF_POPULATED_BUS
)) {
360 pr_debug("%s() - skipping %pOF, already populated\n",
365 auxdata
= of_dev_lookup(lookup
, bus
);
367 bus_id
= auxdata
->name
;
368 platform_data
= auxdata
->platform_data
;
371 if (of_device_is_compatible(bus
, "arm,primecell")) {
373 * Don't return an error here to keep compatibility with older
376 of_amba_device_create(bus
, bus_id
, platform_data
, parent
);
380 dev
= of_platform_device_create_pdata(bus
, bus_id
, platform_data
, parent
);
381 if (!dev
|| !of_match_node(matches
, bus
))
384 for_each_child_of_node_scoped(bus
, child
) {
385 pr_debug(" create child: %pOF\n", child
);
386 rc
= of_platform_bus_create(child
, matches
, lookup
, &dev
->dev
, strict
);
390 of_node_set_flag(bus
, OF_POPULATED_BUS
);
395 * of_platform_bus_probe() - Probe the device-tree for platform buses
396 * @root: parent of the first level to probe or NULL for the root of the tree
397 * @matches: match table for bus nodes
398 * @parent: parent to hook devices from, NULL for toplevel
400 * Note that children of the provided root are not instantiated as devices
401 * unless the specified root itself matches the bus list and is not NULL.
403 int of_platform_bus_probe(struct device_node
*root
,
404 const struct of_device_id
*matches
,
405 struct device
*parent
)
407 struct device_node
*child
;
410 root
= root
? of_node_get(root
) : of_find_node_by_path("/");
414 pr_debug("%s()\n", __func__
);
415 pr_debug(" starting at: %pOF\n", root
);
417 /* Do a self check of bus type, if there's a match, create children */
418 if (of_match_node(matches
, root
)) {
419 rc
= of_platform_bus_create(root
, matches
, NULL
, parent
, false);
420 } else for_each_child_of_node(root
, child
) {
421 if (!of_match_node(matches
, child
))
423 rc
= of_platform_bus_create(child
, matches
, NULL
, parent
, false);
433 EXPORT_SYMBOL(of_platform_bus_probe
);
436 * of_platform_populate() - Populate platform_devices from device tree data
437 * @root: parent of the first level to probe or NULL for the root of the tree
438 * @matches: match table, NULL to use the default
439 * @lookup: auxdata table for matching id and platform_data with device nodes
440 * @parent: parent to hook devices from, NULL for toplevel
442 * Similar to of_platform_bus_probe(), this function walks the device tree
443 * and creates devices from nodes. It differs in that it follows the modern
444 * convention of requiring all device nodes to have a 'compatible' property,
445 * and it is suitable for creating devices which are children of the root
446 * node (of_platform_bus_probe will only create children of the root which
447 * are selected by the @matches argument).
449 * New board support should be using this function instead of
450 * of_platform_bus_probe().
452 * Return: 0 on success, < 0 on failure.
454 int of_platform_populate(struct device_node
*root
,
455 const struct of_device_id
*matches
,
456 const struct of_dev_auxdata
*lookup
,
457 struct device
*parent
)
461 root
= root
? of_node_get(root
) : of_find_node_by_path("/");
465 pr_debug("%s()\n", __func__
);
466 pr_debug(" starting at: %pOF\n", root
);
468 device_links_supplier_sync_state_pause();
469 for_each_child_of_node_scoped(root
, child
) {
470 rc
= of_platform_bus_create(child
, matches
, lookup
, parent
, true);
474 device_links_supplier_sync_state_resume();
476 of_node_set_flag(root
, OF_POPULATED_BUS
);
481 EXPORT_SYMBOL_GPL(of_platform_populate
);
483 int of_platform_default_populate(struct device_node
*root
,
484 const struct of_dev_auxdata
*lookup
,
485 struct device
*parent
)
487 return of_platform_populate(root
, of_default_bus_match_table
, lookup
,
490 EXPORT_SYMBOL_GPL(of_platform_default_populate
);
492 static const struct of_device_id reserved_mem_matches
[] = {
493 { .compatible
= "phram" },
494 { .compatible
= "qcom,rmtfs-mem" },
495 { .compatible
= "qcom,cmd-db" },
496 { .compatible
= "qcom,smem" },
497 { .compatible
= "ramoops" },
498 { .compatible
= "nvmem-rmem" },
499 { .compatible
= "google,open-dice" },
503 static int __init
of_platform_default_populate_init(void)
505 struct device_node
*node
;
507 device_links_supplier_sync_state_pause();
509 if (IS_ENABLED(CONFIG_PPC
)) {
510 struct device_node
*boot_display
= NULL
;
511 struct platform_device
*dev
;
512 int display_number
= 0;
515 /* Check if we have a MacOS display without a node spec */
516 if (of_property_present(of_chosen
, "linux,bootx-noscreen")) {
518 * The old code tried to work out which node was the MacOS
519 * display based on the address. I'm dropping that since the
520 * lack of a node spec only happens with old BootX versions
521 * (users can update) and with this code, they'll still get
522 * a display (just not the palette hacks).
524 dev
= platform_device_alloc("bootx-noscreen", 0);
527 ret
= platform_device_add(dev
);
529 platform_device_put(dev
);
535 * For OF framebuffers, first create the device for the boot display,
536 * then for the other framebuffers. Only fail for the boot display;
537 * ignore errors for the rest.
539 for_each_node_by_type(node
, "display") {
540 if (!of_get_property(node
, "linux,opened", NULL
) ||
541 !of_get_property(node
, "linux,boot-display", NULL
))
543 dev
= of_platform_device_create(node
, "of-display", NULL
);
551 for_each_node_by_type(node
, "display") {
553 const char *of_display_format
= "of-display.%d";
555 if (!of_get_property(node
, "linux,opened", NULL
) || node
== boot_display
)
557 ret
= snprintf(buf
, sizeof(buf
), of_display_format
, display_number
++);
558 if (ret
< sizeof(buf
))
559 of_platform_device_create(node
, buf
, NULL
);
564 * Handle certain compatibles explicitly, since we don't want to create
565 * platform_devices for every node in /reserved-memory with a
568 for_each_matching_node(node
, reserved_mem_matches
)
569 of_platform_device_create(node
, NULL
, NULL
);
571 node
= of_find_node_by_path("/firmware");
573 of_platform_populate(node
, NULL
, NULL
, NULL
);
577 node
= of_get_compatible_child(of_chosen
, "simple-framebuffer");
580 * Since a "simple-framebuffer" device is already added
581 * here, disable the Generic System Framebuffers (sysfb)
582 * to prevent it from registering another device for the
583 * system framebuffer later (e.g: using the screen_info
584 * data that may had been filled as well).
586 * This can happen for example on DT systems that do EFI
587 * booting and may provide a GOP handle to the EFI stub.
590 of_platform_device_create(node
, NULL
, NULL
);
594 /* Populate everything else. */
595 of_platform_default_populate(NULL
, NULL
, NULL
);
600 arch_initcall_sync(of_platform_default_populate_init
);
602 static int __init
of_platform_sync_state_init(void)
604 device_links_supplier_sync_state_resume();
607 late_initcall_sync(of_platform_sync_state_init
);
609 int of_platform_device_destroy(struct device
*dev
, void *data
)
611 /* Do not touch devices not populated from the device tree */
612 if (!dev
->of_node
|| !of_node_check_flag(dev
->of_node
, OF_POPULATED
))
615 /* Recurse for any nodes that were treated as busses */
616 if (of_node_check_flag(dev
->of_node
, OF_POPULATED_BUS
))
617 device_for_each_child(dev
, NULL
, of_platform_device_destroy
);
619 of_node_clear_flag(dev
->of_node
, OF_POPULATED
);
620 of_node_clear_flag(dev
->of_node
, OF_POPULATED_BUS
);
622 if (dev
->bus
== &platform_bus_type
)
623 platform_device_unregister(to_platform_device(dev
));
624 #ifdef CONFIG_ARM_AMBA
625 else if (dev
->bus
== &amba_bustype
)
626 amba_device_unregister(to_amba_device(dev
));
631 EXPORT_SYMBOL_GPL(of_platform_device_destroy
);
634 * of_platform_depopulate() - Remove devices populated from device tree
635 * @parent: device which children will be removed
637 * Complementary to of_platform_populate(), this function removes children
638 * of the given device (and, recursively, their children) that have been
639 * created from their respective device tree nodes (and only those,
640 * leaving others - eg. manually created - unharmed).
642 void of_platform_depopulate(struct device
*parent
)
644 if (parent
->of_node
&& of_node_check_flag(parent
->of_node
, OF_POPULATED_BUS
)) {
645 device_for_each_child_reverse(parent
, NULL
, of_platform_device_destroy
);
646 of_node_clear_flag(parent
->of_node
, OF_POPULATED_BUS
);
649 EXPORT_SYMBOL_GPL(of_platform_depopulate
);
651 static void devm_of_platform_populate_release(struct device
*dev
, void *res
)
653 of_platform_depopulate(*(struct device
**)res
);
657 * devm_of_platform_populate() - Populate platform_devices from device tree data
658 * @dev: device that requested to populate from device tree data
660 * Similar to of_platform_populate(), but will automatically call
661 * of_platform_depopulate() when the device is unbound from the bus.
663 * Return: 0 on success, < 0 on failure.
665 int devm_of_platform_populate(struct device
*dev
)
673 ptr
= devres_alloc(devm_of_platform_populate_release
,
674 sizeof(*ptr
), GFP_KERNEL
);
678 ret
= of_platform_populate(dev
->of_node
, NULL
, NULL
, dev
);
683 devres_add(dev
, ptr
);
688 EXPORT_SYMBOL_GPL(devm_of_platform_populate
);
690 static int devm_of_platform_match(struct device
*dev
, void *res
, void *data
)
692 struct device
**ptr
= res
;
703 * devm_of_platform_depopulate() - Remove devices populated from device tree
704 * @dev: device that requested to depopulate from device tree data
706 * Complementary to devm_of_platform_populate(), this function removes children
707 * of the given device (and, recursively, their children) that have been
708 * created from their respective device tree nodes (and only those,
709 * leaving others - eg. manually created - unharmed).
711 void devm_of_platform_depopulate(struct device
*dev
)
715 ret
= devres_release(dev
, devm_of_platform_populate_release
,
716 devm_of_platform_match
, dev
);
720 EXPORT_SYMBOL_GPL(devm_of_platform_depopulate
);
722 #ifdef CONFIG_OF_DYNAMIC
723 static int of_platform_notify(struct notifier_block
*nb
,
724 unsigned long action
, void *arg
)
726 struct of_reconfig_data
*rd
= arg
;
727 struct platform_device
*pdev_parent
, *pdev
;
729 struct device_node
*parent
;
731 switch (of_reconfig_get_state_change(action
, rd
)) {
732 case OF_RECONFIG_CHANGE_ADD
:
733 parent
= rd
->dn
->parent
;
734 /* verify that the parent is a bus (or the root node) */
735 if (!of_node_is_root(parent
) &&
736 !of_node_check_flag(parent
, OF_POPULATED_BUS
))
737 return NOTIFY_OK
; /* not for us */
739 /* already populated? (driver using of_populate manually) */
740 if (of_node_check_flag(rd
->dn
, OF_POPULATED
))
744 * Clear the flag before adding the device so that fw_devlink
745 * doesn't skip adding consumers to this device.
747 rd
->dn
->fwnode
.flags
&= ~FWNODE_FLAG_NOT_DEVICE
;
748 /* pdev_parent may be NULL when no bus platform device */
749 pdev_parent
= of_find_device_by_node(parent
);
750 pdev
= of_platform_device_create(rd
->dn
, NULL
,
751 pdev_parent
? &pdev_parent
->dev
: NULL
);
752 platform_device_put(pdev_parent
);
755 pr_err("%s: failed to create for '%pOF'\n",
757 /* of_platform_device_create tosses the error code */
758 return notifier_from_errno(-EINVAL
);
762 case OF_RECONFIG_CHANGE_REMOVE
:
764 /* already depopulated? */
765 if (!of_node_check_flag(rd
->dn
, OF_POPULATED
))
768 /* find our device by node */
769 pdev
= of_find_device_by_node(rd
->dn
);
771 return NOTIFY_OK
; /* no? not meant for us */
773 /* unregister takes one ref away */
774 of_platform_device_destroy(&pdev
->dev
, &children_left
);
776 /* and put the reference of the find */
777 platform_device_put(pdev
);
784 static struct notifier_block platform_of_notifier
= {
785 .notifier_call
= of_platform_notify
,
788 void of_platform_register_reconfig_notifier(void)
790 WARN_ON(of_reconfig_notifier_register(&platform_of_notifier
));
792 #endif /* CONFIG_OF_DYNAMIC */
794 #endif /* CONFIG_OF_ADDRESS */