Merge tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm...
[linux-2.6.git] / drivers / of / platform.c
blob404d1daebefa7d7a5d02cbfb611e9585077c00b0
1 /*
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;
39 /**
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)
47 struct device *dev;
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)
55 #include <asm/dcr.h>
56 #endif
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.
67 /**
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;
79 const __be32 *reg;
80 u64 addr;
81 const __be32 *addrp;
82 int magic;
84 #ifdef CONFIG_PPC_DCR
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);
90 if (reg) {
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);
98 return;
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);
108 if (reg) {
109 if (of_can_translate_address(node)) {
110 addr = of_translate_address(node, reg);
111 } else {
112 addrp = of_get_address(node, 0, NULL, NULL);
113 if (addrp)
114 addr = of_read_number(addrp, 1);
115 else
116 addr = OF_BAD_ADDR;
118 if (addr != OF_BAD_ADDR) {
119 dev_set_name(dev, "%llx.%s",
120 (unsigned long long)addr, node->name);
121 return;
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,
140 const char *bus_id,
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);
148 if (!dev)
149 return NULL;
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)
154 num_reg++;
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);
160 if (!res) {
161 platform_device_put(dev);
162 return NULL;
165 dev->num_resources = num_reg + num_irq;
166 dev->resource = res;
167 for (i = 0; i < num_reg; i++, res++) {
168 rc = of_address_to_resource(np, i, res);
169 WARN_ON(rc);
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;
177 #endif
178 dev->dev.parent = parent;
180 if (bus_id)
181 dev_set_name(&dev->dev, "%s", bus_id);
182 else
183 of_device_make_bus_id(&dev->dev);
185 return 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,
201 const char *bus_id,
202 void *platform_data,
203 struct device *parent)
205 struct platform_device *dev;
207 if (!of_device_is_available(np))
208 return NULL;
210 dev = of_device_alloc(np, bus_id, parent);
211 if (!dev)
212 return NULL;
214 #if defined(CONFIG_MICROBLAZE)
215 dev->archdata.dma_mask = 0xffffffffUL;
216 #endif
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);
230 return NULL;
233 return 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,
246 const char *bus_id,
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,
255 const char *bus_id,
256 void *platform_data,
257 struct device *parent)
259 struct amba_device *dev;
260 const void *prop;
261 int i, ret;
263 pr_debug("Creating amba device %s\n", node->full_name);
265 if (!of_device_is_available(node))
266 return NULL;
268 dev = amba_device_alloc(NULL, 0, 0);
269 if (!dev) {
270 pr_err("%s(): amba_device_alloc() failed for %s\n",
271 __func__, node->full_name);
272 return NULL;
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;
280 if (bus_id)
281 dev_set_name(&dev->dev, "%s", bus_id);
282 else
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);
287 if (prop)
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);
295 if (ret) {
296 pr_err("%s(): of_address_to_resource() failed (%d) for %s\n",
297 __func__, ret, node->full_name);
298 goto err_free;
301 ret = amba_device_add(dev, &iomem_resource);
302 if (ret) {
303 pr_err("%s(): amba_device_add() failed (%d) for %s\n",
304 __func__, ret, node->full_name);
305 goto err_free;
308 return dev;
310 err_free:
311 amba_device_put(dev);
312 return NULL;
314 #else /* CONFIG_ARM_AMBA */
315 static struct amba_device *of_amba_device_create(struct device_node *node,
316 const char *bus_id,
317 void *platform_data,
318 struct device *parent)
320 return NULL;
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)
330 struct resource res;
332 if (!lookup)
333 return NULL;
335 for(; lookup->compatible != NULL; lookup++) {
336 if (!of_device_is_compatible(np, lookup->compatible))
337 continue;
338 if (!of_address_to_resource(np, 0, &res))
339 if (res.start != lookup->phys_addr)
340 continue;
341 pr_debug("%s: devname=%s\n", np->full_name, lookup->name);
342 return lookup;
345 return NULL;
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;
369 int rc = 0;
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);
375 return 0;
378 auxdata = of_dev_lookup(lookup, bus);
379 if (auxdata) {
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
387 * device tree files.
389 of_amba_device_create(bus, bus_id, platform_data, parent);
390 return 0;
393 dev = of_platform_device_create_pdata(bus, bus_id, platform_data, parent);
394 if (!dev || !of_match_node(matches, bus))
395 return 0;
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);
400 if (rc) {
401 of_node_put(child);
402 break;
405 return rc;
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;
422 int rc = 0;
424 root = root ? of_node_get(root) : of_find_node_by_path("/");
425 if (!root)
426 return -EINVAL;
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))
436 continue;
437 rc = of_platform_bus_create(child, matches, NULL, parent, false);
438 if (rc)
439 break;
442 of_node_put(root);
443 return rc;
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;
472 int rc = 0;
474 root = root ? of_node_get(root) : of_find_node_by_path("/");
475 if (!root)
476 return -EINVAL;
478 for_each_child_of_node(root, child) {
479 rc = of_platform_bus_create(child, matches, lookup, parent, true);
480 if (rc)
481 break;
484 of_node_put(root);
485 return rc;
487 EXPORT_SYMBOL_GPL(of_platform_populate);
488 #endif /* CONFIG_OF_ADDRESS */