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 #ifdef CONFIG_ARM_AMBA
29 { .compatible
= "arm,amba-bus", },
30 #endif /* CONFIG_ARM_AMBA */
31 {} /* Empty terminated list */
34 static int of_dev_node_match(struct device
*dev
, void *data
)
36 return dev
->of_node
== data
;
40 * of_find_device_by_node - Find the platform_device associated with a node
41 * @np: Pointer to device tree node
43 * Returns platform_device pointer, or NULL if not found
45 struct platform_device
*of_find_device_by_node(struct device_node
*np
)
49 dev
= bus_find_device(&platform_bus_type
, NULL
, np
, of_dev_node_match
);
50 return dev
? to_platform_device(dev
) : NULL
;
52 EXPORT_SYMBOL(of_find_device_by_node
);
54 #if defined(CONFIG_PPC_DCR)
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 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.
75 void of_device_make_bus_id(struct device
*dev
)
77 static atomic_t bus_no_reg_magic
;
78 struct device_node
*node
= dev
->of_node
;
86 * If it's a DCR based device, use 'd' for native DCRs
87 * and 'D' for MMIO DCRs.
89 reg
= of_get_property(node
, "dcr-reg", NULL
);
91 #ifdef CONFIG_PPC_DCR_NATIVE
92 dev_set_name(dev
, "d%x.%s", *reg
, node
->name
);
93 #else /* CONFIG_PPC_DCR_NATIVE */
94 u64 addr
= of_translate_dcr_address(node
, *reg
, NULL
);
95 if (addr
!= OF_BAD_ADDR
) {
96 dev_set_name(dev
, "D%llx.%s",
97 (unsigned long long)addr
, node
->name
);
100 #endif /* !CONFIG_PPC_DCR_NATIVE */
102 #endif /* CONFIG_PPC_DCR */
105 * For MMIO, get the physical address
107 reg
= of_get_property(node
, "reg", NULL
);
109 if (of_can_translate_address(node
)) {
110 addr
= of_translate_address(node
, reg
);
112 addrp
= of_get_address(node
, 0, NULL
, NULL
);
114 addr
= of_read_number(addrp
, 1);
118 if (addr
!= OF_BAD_ADDR
) {
119 dev_set_name(dev
, "%llx.%s",
120 (unsigned long long)addr
, node
->name
);
126 * No BusID, use the node name and add a globally incremented
127 * counter (and pray...)
129 magic
= atomic_add_return(1, &bus_no_reg_magic
);
130 dev_set_name(dev
, "%s.%d", node
->name
, magic
- 1);
134 * of_device_alloc - Allocate and initialize an of_device
135 * @np: device node to assign to device
136 * @bus_id: Name to assign to the device. May be null to use default name.
137 * @parent: Parent device.
139 struct platform_device
*of_device_alloc(struct device_node
*np
,
141 struct device
*parent
)
143 struct platform_device
*dev
;
144 int rc
, i
, num_reg
= 0, num_irq
;
145 struct resource
*res
, temp_res
;
147 dev
= platform_device_alloc("", -1);
151 /* count the io and irq resources */
152 if (of_can_translate_address(np
))
153 while (of_address_to_resource(np
, num_reg
, &temp_res
) == 0)
155 num_irq
= of_irq_count(np
);
157 /* Populate the resource table */
158 if (num_irq
|| num_reg
) {
159 res
= kzalloc(sizeof(*res
) * (num_irq
+ num_reg
), GFP_KERNEL
);
161 platform_device_put(dev
);
165 dev
->num_resources
= num_reg
+ num_irq
;
167 for (i
= 0; i
< num_reg
; i
++, res
++) {
168 rc
= of_address_to_resource(np
, i
, res
);
171 WARN_ON(of_irq_to_resource_table(np
, res
, num_irq
) != num_irq
);
174 dev
->dev
.of_node
= of_node_get(np
);
175 #if defined(CONFIG_MICROBLAZE)
176 dev
->dev
.dma_mask
= &dev
->archdata
.dma_mask
;
178 dev
->dev
.parent
= parent
;
181 dev_set_name(&dev
->dev
, "%s", bus_id
);
183 of_device_make_bus_id(&dev
->dev
);
187 EXPORT_SYMBOL(of_device_alloc
);
190 * of_platform_device_create_pdata - Alloc, initialize and register an of_device
191 * @np: pointer to node to create device for
192 * @bus_id: name to assign device
193 * @platform_data: pointer to populate platform_data pointer with
194 * @parent: Linux device model parent device.
196 * Returns pointer to created platform device, or NULL if a device was not
197 * registered. Unavailable devices will not get registered.
199 static struct platform_device
*of_platform_device_create_pdata(
200 struct device_node
*np
,
203 struct device
*parent
)
205 struct platform_device
*dev
;
207 if (!of_device_is_available(np
))
210 dev
= of_device_alloc(np
, bus_id
, parent
);
214 #if defined(CONFIG_MICROBLAZE)
215 dev
->archdata
.dma_mask
= 0xffffffffUL
;
217 dev
->dev
.coherent_dma_mask
= DMA_BIT_MASK(32);
218 if (!dev
->dev
.dma_mask
)
219 dev
->dev
.dma_mask
= &dev
->dev
.coherent_dma_mask
;
220 dev
->dev
.bus
= &platform_bus_type
;
221 dev
->dev
.platform_data
= platform_data
;
223 /* We do not fill the DMA ops for platform devices by default.
224 * This is currently the responsibility of the platform code
225 * to do such, possibly using a device notifier
228 if (of_device_add(dev
) != 0) {
229 platform_device_put(dev
);
237 * of_platform_device_create - Alloc, initialize and register an of_device
238 * @np: pointer to node to create device for
239 * @bus_id: name to assign device
240 * @parent: Linux device model parent device.
242 * Returns pointer to created platform device, or NULL if a device was not
243 * registered. Unavailable devices will not get registered.
245 struct platform_device
*of_platform_device_create(struct device_node
*np
,
247 struct device
*parent
)
249 return of_platform_device_create_pdata(np
, bus_id
, NULL
, parent
);
251 EXPORT_SYMBOL(of_platform_device_create
);
253 #ifdef CONFIG_ARM_AMBA
254 static struct amba_device
*of_amba_device_create(struct device_node
*node
,
257 struct device
*parent
)
259 struct amba_device
*dev
;
263 pr_debug("Creating amba device %s\n", node
->full_name
);
265 if (!of_device_is_available(node
))
268 dev
= amba_device_alloc(NULL
, 0, 0);
270 pr_err("%s(): amba_device_alloc() failed for %s\n",
271 __func__
, node
->full_name
);
275 /* setup generic device info */
276 dev
->dev
.coherent_dma_mask
= ~0;
277 dev
->dev
.of_node
= of_node_get(node
);
278 dev
->dev
.parent
= parent
;
279 dev
->dev
.platform_data
= platform_data
;
281 dev_set_name(&dev
->dev
, "%s", bus_id
);
283 of_device_make_bus_id(&dev
->dev
);
285 /* Allow the HW Peripheral ID to be overridden */
286 prop
= of_get_property(node
, "arm,primecell-periphid", NULL
);
288 dev
->periphid
= of_read_ulong(prop
, 1);
290 /* Decode the IRQs and address ranges */
291 for (i
= 0; i
< AMBA_NR_IRQS
; i
++)
292 dev
->irq
[i
] = irq_of_parse_and_map(node
, i
);
294 ret
= of_address_to_resource(node
, 0, &dev
->res
);
296 pr_err("%s(): of_address_to_resource() failed (%d) for %s\n",
297 __func__
, ret
, node
->full_name
);
301 ret
= amba_device_add(dev
, &iomem_resource
);
303 pr_err("%s(): amba_device_add() failed (%d) for %s\n",
304 __func__
, ret
, node
->full_name
);
311 amba_device_put(dev
);
314 #else /* CONFIG_ARM_AMBA */
315 static struct amba_device
*of_amba_device_create(struct device_node
*node
,
318 struct device
*parent
)
322 #endif /* CONFIG_ARM_AMBA */
325 * of_devname_lookup() - Given a device node, lookup the preferred Linux name
327 static const struct of_dev_auxdata
*of_dev_lookup(const struct of_dev_auxdata
*lookup
,
328 struct device_node
*np
)
335 for(; lookup
->compatible
!= NULL
; lookup
++) {
336 if (!of_device_is_compatible(np
, lookup
->compatible
))
338 if (!of_address_to_resource(np
, 0, &res
))
339 if (res
.start
!= lookup
->phys_addr
)
341 pr_debug("%s: devname=%s\n", np
->full_name
, lookup
->name
);
349 * of_platform_bus_create() - Create a device for a node and its children.
350 * @bus: device node of the bus to instantiate
351 * @matches: match table for bus nodes
352 * @lookup: auxdata table for matching id and platform_data with device nodes
353 * @parent: parent for new device, or NULL for top level.
354 * @strict: require compatible property
356 * Creates a platform_device for the provided device_node, and optionally
357 * recursively create devices for all the child nodes.
359 static int of_platform_bus_create(struct device_node
*bus
,
360 const struct of_device_id
*matches
,
361 const struct of_dev_auxdata
*lookup
,
362 struct device
*parent
, bool strict
)
364 const struct of_dev_auxdata
*auxdata
;
365 struct device_node
*child
;
366 struct platform_device
*dev
;
367 const char *bus_id
= NULL
;
368 void *platform_data
= NULL
;
371 /* Make sure it has a compatible property */
372 if (strict
&& (!of_get_property(bus
, "compatible", NULL
))) {
373 pr_debug("%s() - skipping %s, no compatible prop\n",
374 __func__
, bus
->full_name
);
378 auxdata
= of_dev_lookup(lookup
, bus
);
380 bus_id
= auxdata
->name
;
381 platform_data
= auxdata
->platform_data
;
384 if (of_device_is_compatible(bus
, "arm,primecell")) {
386 * Don't return an error here to keep compatibility with older
389 of_amba_device_create(bus
, bus_id
, platform_data
, parent
);
393 dev
= of_platform_device_create_pdata(bus
, bus_id
, platform_data
, parent
);
394 if (!dev
|| !of_match_node(matches
, bus
))
397 for_each_child_of_node(bus
, child
) {
398 pr_debug(" create child: %s\n", child
->full_name
);
399 rc
= of_platform_bus_create(child
, matches
, lookup
, &dev
->dev
, strict
);
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("of_platform_bus_probe()\n");
429 pr_debug(" starting at: %s\n", root
->full_name
);
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);
445 EXPORT_SYMBOL(of_platform_bus_probe
);
448 * of_platform_populate() - Populate platform_devices from device tree data
449 * @root: parent of the first level to probe or NULL for the root of the tree
450 * @matches: match table, NULL to use the default
451 * @lookup: auxdata table for matching id and platform_data with device nodes
452 * @parent: parent to hook devices from, NULL for toplevel
454 * Similar to of_platform_bus_probe(), this function walks the device tree
455 * and creates devices from nodes. It differs in that it follows the modern
456 * convention of requiring all device nodes to have a 'compatible' property,
457 * and it is suitable for creating devices which are children of the root
458 * node (of_platform_bus_probe will only create children of the root which
459 * are selected by the @matches argument).
461 * New board support should be using this function instead of
462 * of_platform_bus_probe().
464 * Returns 0 on success, < 0 on failure.
466 int of_platform_populate(struct device_node
*root
,
467 const struct of_device_id
*matches
,
468 const struct of_dev_auxdata
*lookup
,
469 struct device
*parent
)
471 struct device_node
*child
;
474 root
= root
? of_node_get(root
) : of_find_node_by_path("/");
478 for_each_child_of_node(root
, child
) {
479 rc
= of_platform_bus_create(child
, matches
, lookup
, parent
, true);
487 EXPORT_SYMBOL_GPL(of_platform_populate
);
488 #endif /* CONFIG_OF_ADDRESS */