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 #if !defined(CONFIG_SPARC)
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
;
85 * If it's a DCR based device, use 'd' for native DCRs
86 * and 'D' for MMIO DCRs.
88 reg
= of_get_property(node
, "dcr-reg", NULL
);
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
);
99 #endif /* !CONFIG_PPC_DCR_NATIVE */
101 #endif /* CONFIG_PPC_DCR */
104 * For MMIO, get the physical address
106 reg
= of_get_property(node
, "reg", NULL
);
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
);
117 * No BusID, use the node name and add a globally incremented
118 * counter (and pray...)
120 magic
= atomic_add_return(1, &bus_no_reg_magic
);
121 dev_set_name(dev
, "%s.%d", node
->name
, magic
- 1);
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.
130 struct platform_device
*of_device_alloc(struct device_node
*np
,
132 struct device
*parent
)
134 struct platform_device
*dev
;
135 int rc
, i
, num_reg
= 0, num_irq
;
136 struct resource
*res
, temp_res
;
138 dev
= platform_device_alloc("", -1);
142 /* count the io and irq resources */
143 while (of_address_to_resource(np
, num_reg
, &temp_res
) == 0)
145 num_irq
= of_irq_count(np
);
147 /* Populate the resource table */
148 if (num_irq
|| num_reg
) {
149 res
= kzalloc(sizeof(*res
) * (num_irq
+ num_reg
), GFP_KERNEL
);
151 platform_device_put(dev
);
155 dev
->num_resources
= num_reg
+ num_irq
;
157 for (i
= 0; i
< num_reg
; i
++, res
++) {
158 rc
= of_address_to_resource(np
, i
, res
);
161 WARN_ON(of_irq_to_resource_table(np
, res
, num_irq
) != num_irq
);
164 dev
->dev
.of_node
= of_node_get(np
);
165 #if defined(CONFIG_MICROBLAZE)
166 dev
->dev
.dma_mask
= &dev
->archdata
.dma_mask
;
168 dev
->dev
.parent
= parent
;
171 dev_set_name(&dev
->dev
, "%s", bus_id
);
173 of_device_make_bus_id(&dev
->dev
);
177 EXPORT_SYMBOL(of_device_alloc
);
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.
186 * Returns pointer to created platform device, or NULL if a device was not
187 * registered. Unavailable devices will not get registered.
189 struct platform_device
*of_platform_device_create_pdata(
190 struct device_node
*np
,
193 struct device
*parent
)
195 struct platform_device
*dev
;
197 if (!of_device_is_available(np
))
200 dev
= of_device_alloc(np
, bus_id
, parent
);
204 #if defined(CONFIG_MICROBLAZE)
205 dev
->archdata
.dma_mask
= 0xffffffffUL
;
207 dev
->dev
.coherent_dma_mask
= DMA_BIT_MASK(32);
208 dev
->dev
.bus
= &platform_bus_type
;
209 dev
->dev
.platform_data
= platform_data
;
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
216 if (of_device_add(dev
) != 0) {
217 platform_device_put(dev
);
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.
230 * Returns pointer to created platform device, or NULL if a device was not
231 * registered. Unavailable devices will not get registered.
233 struct platform_device
*of_platform_device_create(struct device_node
*np
,
235 struct device
*parent
)
237 return of_platform_device_create_pdata(np
, bus_id
, NULL
, parent
);
239 EXPORT_SYMBOL(of_platform_device_create
);
241 #ifdef CONFIG_ARM_AMBA
242 static struct amba_device
*of_amba_device_create(struct device_node
*node
,
245 struct device
*parent
)
247 struct amba_device
*dev
;
251 pr_debug("Creating amba device %s\n", node
->full_name
);
253 if (!of_device_is_available(node
))
256 dev
= kzalloc(sizeof(*dev
), GFP_KERNEL
);
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
;
266 dev_set_name(&dev
->dev
, "%s", bus_id
);
268 of_device_make_bus_id(&dev
->dev
);
270 /* setup amba-specific device info */
273 /* Allow the HW Peripheral ID to be overridden */
274 prop
= of_get_property(node
, "arm,primecell-periphid", NULL
);
276 dev
->periphid
= of_read_ulong(prop
, 1);
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
);
282 ret
= of_address_to_resource(node
, 0, &dev
->res
);
286 ret
= amba_device_register(dev
, &iomem_resource
);
296 #else /* CONFIG_ARM_AMBA */
297 static struct amba_device
*of_amba_device_create(struct device_node
*node
,
300 struct device
*parent
)
304 #endif /* CONFIG_ARM_AMBA */
307 * of_devname_lookup() - Given a device node, lookup the preferred Linux name
309 static const struct of_dev_auxdata
*of_dev_lookup(const struct of_dev_auxdata
*lookup
,
310 struct device_node
*np
)
314 for(; lookup
->name
!= NULL
; lookup
++) {
315 if (!of_device_is_compatible(np
, lookup
->compatible
))
317 if (of_address_to_resource(np
, 0, &res
))
319 if (res
.start
!= lookup
->phys_addr
)
321 pr_debug("%s: devname=%s\n", np
->full_name
, lookup
->name
);
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.
335 * Creates a platform_device for the provided device_node, and optionally
336 * recursively create devices for all the child nodes.
338 static 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
)
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
;
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
);
357 auxdata
= of_dev_lookup(lookup
, bus
);
359 bus_id
= auxdata
->name
;
360 platform_data
= auxdata
->platform_data
;
363 if (of_device_is_compatible(bus
, "arm,primecell")) {
364 of_amba_device_create(bus
, bus_id
, platform_data
, parent
);
368 dev
= of_platform_device_create_pdata(bus
, bus_id
, platform_data
, parent
);
369 if (!dev
|| !of_match_node(matches
, bus
))
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
);
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
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.
392 int of_platform_bus_probe(struct device_node
*root
,
393 const struct of_device_id
*matches
,
394 struct device
*parent
)
396 struct device_node
*child
;
399 root
= root
? of_node_get(root
) : of_find_node_by_path("/");
403 pr_debug("of_platform_bus_probe()\n");
404 pr_debug(" starting at: %s\n", root
->full_name
);
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
))
412 rc
= of_platform_bus_create(child
, matches
, NULL
, parent
, false);
420 EXPORT_SYMBOL(of_platform_bus_probe
);
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
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).
435 * New board support should be using this function instead of
436 * of_platform_bus_probe().
438 * Returns 0 on success, < 0 on failure.
440 int 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
)
445 struct device_node
*child
;
448 root
= root
? of_node_get(root
) : of_find_node_by_path("/");
452 for_each_child_of_node(root
, child
) {
453 rc
= of_platform_bus_create(child
, matches
, lookup
, parent
, true);
461 #endif /* !CONFIG_SPARC */