i2c-eg20t: change timeout value 50msec to 1000msec
[zen-stable.git] / drivers / of / platform.c
blob63b3ec48c203a43f3d8a9d395e459d765fd7f7b0
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 #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.
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 u32 *reg;
80 u64 addr;
81 int magic;
83 #ifdef CONFIG_PPC_DCR
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);
89 if (reg) {
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);
97 return;
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);
107 if (reg) {
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);
112 return;
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,
131 const char *bus_id,
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);
139 if (!dev)
140 return NULL;
142 /* count the io and irq resources */
143 while (of_address_to_resource(np, num_reg, &temp_res) == 0)
144 num_reg++;
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);
150 if (!res) {
151 platform_device_put(dev);
152 return NULL;
155 dev->num_resources = num_reg + num_irq;
156 dev->resource = res;
157 for (i = 0; i < num_reg; i++, res++) {
158 rc = of_address_to_resource(np, i, res);
159 WARN_ON(rc);
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;
167 #endif
168 dev->dev.parent = parent;
170 if (bus_id)
171 dev_set_name(&dev->dev, "%s", bus_id);
172 else
173 of_device_make_bus_id(&dev->dev);
175 return 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,
191 const char *bus_id,
192 void *platform_data,
193 struct device *parent)
195 struct platform_device *dev;
197 if (!of_device_is_available(np))
198 return NULL;
200 dev = of_device_alloc(np, bus_id, parent);
201 if (!dev)
202 return NULL;
204 #if defined(CONFIG_MICROBLAZE)
205 dev->archdata.dma_mask = 0xffffffffUL;
206 #endif
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);
218 return NULL;
221 return 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,
234 const char *bus_id,
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,
243 const char *bus_id,
244 void *platform_data,
245 struct device *parent)
247 struct amba_device *dev;
248 const void *prop;
249 int i, ret;
251 pr_debug("Creating amba device %s\n", node->full_name);
253 if (!of_device_is_available(node))
254 return NULL;
256 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
257 if (!dev)
258 return NULL;
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;
265 if (bus_id)
266 dev_set_name(&dev->dev, "%s", bus_id);
267 else
268 of_device_make_bus_id(&dev->dev);
270 /* setup amba-specific device info */
271 dev->dma_mask = ~0;
273 /* Allow the HW Peripheral ID to be overridden */
274 prop = of_get_property(node, "arm,primecell-periphid", NULL);
275 if (prop)
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);
283 if (ret)
284 goto err_free;
286 ret = amba_device_register(dev, &iomem_resource);
287 if (ret)
288 goto err_free;
290 return dev;
292 err_free:
293 kfree(dev);
294 return NULL;
296 #else /* CONFIG_ARM_AMBA */
297 static struct amba_device *of_amba_device_create(struct device_node *node,
298 const char *bus_id,
299 void *platform_data,
300 struct device *parent)
302 return NULL;
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)
312 struct resource res;
314 if (!lookup)
315 return NULL;
317 for(; lookup->compatible != NULL; lookup++) {
318 if (!of_device_is_compatible(np, lookup->compatible))
319 continue;
320 if (of_address_to_resource(np, 0, &res))
321 continue;
322 if (res.start != lookup->phys_addr)
323 continue;
324 pr_debug("%s: devname=%s\n", np->full_name, lookup->name);
325 return lookup;
328 return NULL;
332 * of_platform_bus_create() - Create a device for a node and its children.
333 * @bus: device node of the bus to instantiate
334 * @matches: match table for bus nodes
335 * @lookup: auxdata table for matching id and platform_data with device nodes
336 * @parent: parent for new device, or NULL for top level.
337 * @strict: require compatible property
339 * Creates a platform_device for the provided device_node, and optionally
340 * recursively create devices for all the child nodes.
342 static int of_platform_bus_create(struct device_node *bus,
343 const struct of_device_id *matches,
344 const struct of_dev_auxdata *lookup,
345 struct device *parent, bool strict)
347 const struct of_dev_auxdata *auxdata;
348 struct device_node *child;
349 struct platform_device *dev;
350 const char *bus_id = NULL;
351 void *platform_data = NULL;
352 int rc = 0;
354 /* Make sure it has a compatible property */
355 if (strict && (!of_get_property(bus, "compatible", NULL))) {
356 pr_debug("%s() - skipping %s, no compatible prop\n",
357 __func__, bus->full_name);
358 return 0;
361 auxdata = of_dev_lookup(lookup, bus);
362 if (auxdata) {
363 bus_id = auxdata->name;
364 platform_data = auxdata->platform_data;
367 if (of_device_is_compatible(bus, "arm,primecell")) {
368 of_amba_device_create(bus, bus_id, platform_data, parent);
369 return 0;
372 dev = of_platform_device_create_pdata(bus, bus_id, platform_data, parent);
373 if (!dev || !of_match_node(matches, bus))
374 return 0;
376 for_each_child_of_node(bus, child) {
377 pr_debug(" create child: %s\n", child->full_name);
378 rc = of_platform_bus_create(child, matches, lookup, &dev->dev, strict);
379 if (rc) {
380 of_node_put(child);
381 break;
384 return rc;
388 * of_platform_bus_probe() - Probe the device-tree for platform buses
389 * @root: parent of the first level to probe or NULL for the root of the tree
390 * @matches: match table for bus nodes
391 * @parent: parent to hook devices from, NULL for toplevel
393 * Note that children of the provided root are not instantiated as devices
394 * unless the specified root itself matches the bus list and is not NULL.
396 int of_platform_bus_probe(struct device_node *root,
397 const struct of_device_id *matches,
398 struct device *parent)
400 struct device_node *child;
401 int rc = 0;
403 root = root ? of_node_get(root) : of_find_node_by_path("/");
404 if (!root)
405 return -EINVAL;
407 pr_debug("of_platform_bus_probe()\n");
408 pr_debug(" starting at: %s\n", root->full_name);
410 /* Do a self check of bus type, if there's a match, create children */
411 if (of_match_node(matches, root)) {
412 rc = of_platform_bus_create(root, matches, NULL, parent, false);
413 } else for_each_child_of_node(root, child) {
414 if (!of_match_node(matches, child))
415 continue;
416 rc = of_platform_bus_create(child, matches, NULL, parent, false);
417 if (rc)
418 break;
421 of_node_put(root);
422 return rc;
424 EXPORT_SYMBOL(of_platform_bus_probe);
427 * of_platform_populate() - Populate platform_devices from device tree data
428 * @root: parent of the first level to probe or NULL for the root of the tree
429 * @matches: match table, NULL to use the default
430 * @parent: parent to hook devices from, NULL for toplevel
432 * Similar to of_platform_bus_probe(), this function walks the device tree
433 * and creates devices from nodes. It differs in that it follows the modern
434 * convention of requiring all device nodes to have a 'compatible' property,
435 * and it is suitable for creating devices which are children of the root
436 * node (of_platform_bus_probe will only create children of the root which
437 * are selected by the @matches argument).
439 * New board support should be using this function instead of
440 * of_platform_bus_probe().
442 * Returns 0 on success, < 0 on failure.
444 int of_platform_populate(struct device_node *root,
445 const struct of_device_id *matches,
446 const struct of_dev_auxdata *lookup,
447 struct device *parent)
449 struct device_node *child;
450 int rc = 0;
452 root = root ? of_node_get(root) : of_find_node_by_path("/");
453 if (!root)
454 return -EINVAL;
456 for_each_child_of_node(root, child) {
457 rc = of_platform_bus_create(child, matches, lookup, parent, true);
458 if (rc)
459 break;
462 of_node_put(root);
463 return rc;
465 #endif /* !CONFIG_SPARC */