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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
7 *
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.
12 *
13 */
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>
25
26const 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 */
32};
33
34static int of_dev_node_match(struct device *dev, void *data)
35{
36 return dev->of_node == data;
37}
38
39/**
40 * of_find_device_by_node - Find the platform_device associated with a node
41 * @np: Pointer to device tree node
42 *
43 * Returns platform_device pointer, or NULL if not found
44 */
45struct platform_device *of_find_device_by_node(struct device_node *np)
46{
47 struct device *dev;
48
49 dev = bus_find_device(&platform_bus_type, NULL, np, of_dev_node_match);
50 return dev ? to_platform_device(dev) : NULL;
51}
52EXPORT_SYMBOL(of_find_device_by_node);
53
54#if defined(CONFIG_PPC_DCR)
55#include <asm/dcr.h>
56#endif
57
58#if !defined(CONFIG_SPARC)
59/*
60 * The following routines scan a subtree and registers a device for
61 * each applicable node.
62 *
63 * Note: sparc doesn't use these routines because it has a different
64 * mechanism for creating devices from device tree nodes.
65 */
66
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
70 *
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.
74 */
75void of_device_make_bus_id(struct device *dev)
76{
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;
82
83#ifdef CONFIG_PPC_DCR
84 /*
85 * If it's a DCR based device, use 'd' for native DCRs
86 * and 'D' for MMIO DCRs.
87 */
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;
98 }
99#endif /* !CONFIG_PPC_DCR_NATIVE */
100 }
101#endif /* CONFIG_PPC_DCR */
102
103 /*
104 * For MMIO, get the physical address
105 */
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;
113 }
114 }
115
116 /*
117 * No BusID, use the node name and add a globally incremented
118 * counter (and pray...)
119 */
120 magic = atomic_add_return(1, &bus_no_reg_magic);
121 dev_set_name(dev, "%s.%d", node->name, magic - 1);
122}
123
124/**
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.
129 */
130struct platform_device *of_device_alloc(struct device_node *np,
131 const char *bus_id,
132 struct device *parent)
133{
134 struct platform_device *dev;
135 int rc, i, num_reg = 0, num_irq;
136 struct resource *res, temp_res;
137
138 dev = platform_device_alloc("", -1);
139 if (!dev)
140 return NULL;
141
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);
146
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;
153 }
154
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);
160 }
161 WARN_ON(of_irq_to_resource_table(np, res, num_irq) != num_irq);
162 }
163
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;
169
170 if (bus_id)
171 dev_set_name(&dev->dev, "%s", bus_id);
172 else
173 of_device_make_bus_id(&dev->dev);
174
175 return dev;
176}
177EXPORT_SYMBOL(of_device_alloc);
178
179/**
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.
185 *
186 * Returns pointer to created platform device, or NULL if a device was not
187 * registered. Unavailable devices will not get registered.
188 */
189struct 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)
194{
195 struct platform_device *dev;
196
197 if (!of_device_is_available(np))
198 return NULL;
199
200 dev = of_device_alloc(np, bus_id, parent);
201 if (!dev)
202 return NULL;
203
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;
210
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
214 */
215
216 if (of_device_add(dev) != 0) {
217 platform_device_put(dev);
218 return NULL;
219 }
220
221 return dev;
222}
223
224/**
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.
229 *
230 * Returns pointer to created platform device, or NULL if a device was not
231 * registered. Unavailable devices will not get registered.
232 */
233struct platform_device *of_platform_device_create(struct device_node *np,
234 const char *bus_id,
235 struct device *parent)
236{
237 return of_platform_device_create_pdata(np, bus_id, NULL, parent);
238}
239EXPORT_SYMBOL(of_platform_device_create);
240
241#ifdef CONFIG_ARM_AMBA
242static struct amba_device *of_amba_device_create(struct device_node *node,
243 const char *bus_id,
244 void *platform_data,
245 struct device *parent)
246{
247 struct amba_device *dev;
248 const void *prop;
249 int i, ret;
250
251 pr_debug("Creating amba device %s\n", node->full_name);
252
253 if (!of_device_is_available(node))
254 return NULL;
255
256 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
257 if (!dev)
258 return NULL;
259
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);
269
270 /* setup amba-specific device info */
271 dev->dma_mask = ~0;
272
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);
277
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);
281
282 ret = of_address_to_resource(node, 0, &dev->res);
283 if (ret)
284 goto err_free;
285
286 ret = amba_device_register(dev, &iomem_resource);
287 if (ret)
288 goto err_free;
289
290 return dev;
291
292err_free:
293 kfree(dev);
294 return NULL;
295}
296#else /* CONFIG_ARM_AMBA */
297static struct amba_device *of_amba_device_create(struct device_node *node,
298 const char *bus_id,
299 void *platform_data,
300 struct device *parent)
301{
302 return NULL;
303}
304#endif /* CONFIG_ARM_AMBA */
305
306/**
307 * of_devname_lookup() - Given a device node, lookup the preferred Linux name
308 */
309static const struct of_dev_auxdata *of_dev_lookup(const struct of_dev_auxdata *lookup,
310 struct device_node *np)
311{
312 struct resource res;
313 if (lookup) {
314 for(; lookup->name != NULL; lookup++) {
315 if (!of_device_is_compatible(np, lookup->compatible))
316 continue;
317 if (of_address_to_resource(np, 0, &res))
318 continue;
319 if (res.start != lookup->phys_addr)
320 continue;
321 pr_debug("%s: devname=%s\n", np->full_name, lookup->name);
322 return lookup;
323 }
324 }
325 return NULL;
326}
327
328/**
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.
334 *
335 * Creates a platform_device for the provided device_node, and optionally
336 * recursively create devices for all the child nodes.
337 */
338static 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)
342{
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;
348 int rc = 0;
349
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);
354 return 0;
355 }
356
357 auxdata = of_dev_lookup(lookup, bus);
358 if (auxdata) {
359 bus_id = auxdata->name;
360 platform_data = auxdata->platform_data;
361 }
362
363 if (of_device_is_compatible(bus, "arm,primecell")) {
364 of_amba_device_create(bus, bus_id, platform_data, parent);
365 return 0;
366 }
367
368 dev = of_platform_device_create_pdata(bus, bus_id, platform_data, parent);
369 if (!dev || !of_match_node(matches, bus))
370 return 0;
371
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);
375 if (rc) {
376 of_node_put(child);
377 break;
378 }
379 }
380 return rc;
381}
382
383/**
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
388 *
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.
391 */
392int of_platform_bus_probe(struct device_node *root,
393 const struct of_device_id *matches,
394 struct device *parent)
395{
396 struct device_node *child;
397 int rc = 0;
398
399 root = root ? of_node_get(root) : of_find_node_by_path("/");
400 if (!root)
401 return -EINVAL;
402
403 pr_debug("of_platform_bus_probe()\n");
404 pr_debug(" starting at: %s\n", root->full_name);
405
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))
411 continue;
412 rc = of_platform_bus_create(child, matches, NULL, parent, false);
413 if (rc)
414 break;
415 }
416
417 of_node_put(root);
418 return rc;
419}
420EXPORT_SYMBOL(of_platform_bus_probe);
421
422/**
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
427 *
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).
434 *
435 * New board support should be using this function instead of
436 * of_platform_bus_probe().
437 *
438 * Returns 0 on success, < 0 on failure.
439 */
440int 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)
444{
445 struct device_node *child;
446 int rc = 0;
447
448 root = root ? of_node_get(root) : of_find_node_by_path("/");
449 if (!root)
450 return -EINVAL;
451
452 for_each_child_of_node(root, child) {
453 rc = of_platform_bus_create(child, matches, lookup, parent, true);
454 if (rc)
455 break;
456 }
457
458 of_node_put(root);
459 return rc;
460}
461#endif /* !CONFIG_SPARC */
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
7 *
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.
12 *
13 */
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>
25
26const struct of_device_id of_default_bus_match_table[] = {
27 { .compatible = "simple-bus", },
28 { .compatible = "simple-mfd", },
29#ifdef CONFIG_ARM_AMBA
30 { .compatible = "arm,amba-bus", },
31#endif /* CONFIG_ARM_AMBA */
32 {} /* Empty terminated list */
33};
34EXPORT_SYMBOL(of_default_bus_match_table);
35
36static int of_dev_node_match(struct device *dev, void *data)
37{
38 return dev->of_node == data;
39}
40
41/**
42 * of_find_device_by_node - Find the platform_device associated with a node
43 * @np: Pointer to device tree node
44 *
45 * Returns platform_device pointer, or NULL if not found
46 */
47struct platform_device *of_find_device_by_node(struct device_node *np)
48{
49 struct device *dev;
50
51 dev = bus_find_device(&platform_bus_type, NULL, np, of_dev_node_match);
52 return dev ? to_platform_device(dev) : NULL;
53}
54EXPORT_SYMBOL(of_find_device_by_node);
55
56#ifdef CONFIG_OF_ADDRESS
57/*
58 * The following routines scan a subtree and registers a device for
59 * each applicable node.
60 *
61 * Note: sparc doesn't use these routines because it has a different
62 * mechanism for creating devices from device tree nodes.
63 */
64
65/**
66 * of_device_make_bus_id - Use the device node data to assign a unique name
67 * @dev: pointer to device structure that is linked to a device tree node
68 *
69 * This routine will first try using the translated bus address to
70 * derive a unique name. If it cannot, then it will prepend names from
71 * parent nodes until a unique name can be derived.
72 */
73void of_device_make_bus_id(struct device *dev)
74{
75 struct device_node *node = dev->of_node;
76 const __be32 *reg;
77 u64 addr;
78
79 /* Construct the name, using parent nodes if necessary to ensure uniqueness */
80 while (node->parent) {
81 /*
82 * If the address can be translated, then that is as much
83 * uniqueness as we need. Make it the first component and return
84 */
85 reg = of_get_property(node, "reg", NULL);
86 if (reg && (addr = of_translate_address(node, reg)) != OF_BAD_ADDR) {
87 dev_set_name(dev, dev_name(dev) ? "%llx.%s:%s" : "%llx.%s",
88 (unsigned long long)addr, node->name,
89 dev_name(dev));
90 return;
91 }
92
93 /* format arguments only used if dev_name() resolves to NULL */
94 dev_set_name(dev, dev_name(dev) ? "%s:%s" : "%s",
95 strrchr(node->full_name, '/') + 1, dev_name(dev));
96 node = node->parent;
97 }
98}
99
100/**
101 * of_device_alloc - Allocate and initialize an of_device
102 * @np: device node to assign to device
103 * @bus_id: Name to assign to the device. May be null to use default name.
104 * @parent: Parent device.
105 */
106struct platform_device *of_device_alloc(struct device_node *np,
107 const char *bus_id,
108 struct device *parent)
109{
110 struct platform_device *dev;
111 int rc, i, num_reg = 0, num_irq;
112 struct resource *res, temp_res;
113
114 dev = platform_device_alloc("", -1);
115 if (!dev)
116 return NULL;
117
118 /* count the io and irq resources */
119 while (of_address_to_resource(np, num_reg, &temp_res) == 0)
120 num_reg++;
121 num_irq = of_irq_count(np);
122
123 /* Populate the resource table */
124 if (num_irq || num_reg) {
125 res = kzalloc(sizeof(*res) * (num_irq + num_reg), GFP_KERNEL);
126 if (!res) {
127 platform_device_put(dev);
128 return NULL;
129 }
130
131 dev->num_resources = num_reg + num_irq;
132 dev->resource = res;
133 for (i = 0; i < num_reg; i++, res++) {
134 rc = of_address_to_resource(np, i, res);
135 WARN_ON(rc);
136 }
137 if (of_irq_to_resource_table(np, res, num_irq) != num_irq)
138 pr_debug("not all legacy IRQ resources mapped for %s\n",
139 np->name);
140 }
141
142 dev->dev.of_node = of_node_get(np);
143 dev->dev.parent = parent ? : &platform_bus;
144
145 if (bus_id)
146 dev_set_name(&dev->dev, "%s", bus_id);
147 else
148 of_device_make_bus_id(&dev->dev);
149
150 return dev;
151}
152EXPORT_SYMBOL(of_device_alloc);
153
154static void of_dma_deconfigure(struct device *dev)
155{
156 arch_teardown_dma_ops(dev);
157}
158
159/**
160 * of_platform_device_create_pdata - Alloc, initialize and register an of_device
161 * @np: pointer to node to create device for
162 * @bus_id: name to assign device
163 * @platform_data: pointer to populate platform_data pointer with
164 * @parent: Linux device model parent device.
165 *
166 * Returns pointer to created platform device, or NULL if a device was not
167 * registered. Unavailable devices will not get registered.
168 */
169static struct platform_device *of_platform_device_create_pdata(
170 struct device_node *np,
171 const char *bus_id,
172 void *platform_data,
173 struct device *parent)
174{
175 struct platform_device *dev;
176
177 if (!of_device_is_available(np) ||
178 of_node_test_and_set_flag(np, OF_POPULATED))
179 return NULL;
180
181 dev = of_device_alloc(np, bus_id, parent);
182 if (!dev)
183 goto err_clear_flag;
184
185 dev->dev.bus = &platform_bus_type;
186 dev->dev.platform_data = platform_data;
187 of_dma_configure(&dev->dev, dev->dev.of_node);
188 of_msi_configure(&dev->dev, dev->dev.of_node);
189
190 if (of_device_add(dev) != 0) {
191 of_dma_deconfigure(&dev->dev);
192 platform_device_put(dev);
193 goto err_clear_flag;
194 }
195
196 return dev;
197
198err_clear_flag:
199 of_node_clear_flag(np, OF_POPULATED);
200 return NULL;
201}
202
203/**
204 * of_platform_device_create - Alloc, initialize and register an of_device
205 * @np: pointer to node to create device for
206 * @bus_id: name to assign device
207 * @parent: Linux device model parent device.
208 *
209 * Returns pointer to created platform device, or NULL if a device was not
210 * registered. Unavailable devices will not get registered.
211 */
212struct platform_device *of_platform_device_create(struct device_node *np,
213 const char *bus_id,
214 struct device *parent)
215{
216 return of_platform_device_create_pdata(np, bus_id, NULL, parent);
217}
218EXPORT_SYMBOL(of_platform_device_create);
219
220#ifdef CONFIG_ARM_AMBA
221static struct amba_device *of_amba_device_create(struct device_node *node,
222 const char *bus_id,
223 void *platform_data,
224 struct device *parent)
225{
226 struct amba_device *dev;
227 const void *prop;
228 int i, ret;
229
230 pr_debug("Creating amba device %s\n", node->full_name);
231
232 if (!of_device_is_available(node) ||
233 of_node_test_and_set_flag(node, OF_POPULATED))
234 return NULL;
235
236 dev = amba_device_alloc(NULL, 0, 0);
237 if (!dev) {
238 pr_err("%s(): amba_device_alloc() failed for %s\n",
239 __func__, node->full_name);
240 goto err_clear_flag;
241 }
242
243 /* setup generic device info */
244 dev->dev.of_node = of_node_get(node);
245 dev->dev.parent = parent ? : &platform_bus;
246 dev->dev.platform_data = platform_data;
247 if (bus_id)
248 dev_set_name(&dev->dev, "%s", bus_id);
249 else
250 of_device_make_bus_id(&dev->dev);
251 of_dma_configure(&dev->dev, dev->dev.of_node);
252
253 /* Allow the HW Peripheral ID to be overridden */
254 prop = of_get_property(node, "arm,primecell-periphid", NULL);
255 if (prop)
256 dev->periphid = of_read_ulong(prop, 1);
257
258 /* Decode the IRQs and address ranges */
259 for (i = 0; i < AMBA_NR_IRQS; i++)
260 dev->irq[i] = irq_of_parse_and_map(node, i);
261
262 ret = of_address_to_resource(node, 0, &dev->res);
263 if (ret) {
264 pr_err("%s(): of_address_to_resource() failed (%d) for %s\n",
265 __func__, ret, node->full_name);
266 goto err_free;
267 }
268
269 ret = amba_device_add(dev, &iomem_resource);
270 if (ret) {
271 pr_err("%s(): amba_device_add() failed (%d) for %s\n",
272 __func__, ret, node->full_name);
273 goto err_free;
274 }
275
276 return dev;
277
278err_free:
279 amba_device_put(dev);
280err_clear_flag:
281 of_node_clear_flag(node, OF_POPULATED);
282 return NULL;
283}
284#else /* CONFIG_ARM_AMBA */
285static struct amba_device *of_amba_device_create(struct device_node *node,
286 const char *bus_id,
287 void *platform_data,
288 struct device *parent)
289{
290 return NULL;
291}
292#endif /* CONFIG_ARM_AMBA */
293
294/**
295 * of_devname_lookup() - Given a device node, lookup the preferred Linux name
296 */
297static const struct of_dev_auxdata *of_dev_lookup(const struct of_dev_auxdata *lookup,
298 struct device_node *np)
299{
300 struct resource res;
301
302 if (!lookup)
303 return NULL;
304
305 for(; lookup->compatible != NULL; lookup++) {
306 if (!of_device_is_compatible(np, lookup->compatible))
307 continue;
308 if (!of_address_to_resource(np, 0, &res))
309 if (res.start != lookup->phys_addr)
310 continue;
311 pr_debug("%s: devname=%s\n", np->full_name, lookup->name);
312 return lookup;
313 }
314
315 return NULL;
316}
317
318/**
319 * of_platform_bus_create() - Create a device for a node and its children.
320 * @bus: device node of the bus to instantiate
321 * @matches: match table for bus nodes
322 * @lookup: auxdata table for matching id and platform_data with device nodes
323 * @parent: parent for new device, or NULL for top level.
324 * @strict: require compatible property
325 *
326 * Creates a platform_device for the provided device_node, and optionally
327 * recursively create devices for all the child nodes.
328 */
329static int of_platform_bus_create(struct device_node *bus,
330 const struct of_device_id *matches,
331 const struct of_dev_auxdata *lookup,
332 struct device *parent, bool strict)
333{
334 const struct of_dev_auxdata *auxdata;
335 struct device_node *child;
336 struct platform_device *dev;
337 const char *bus_id = NULL;
338 void *platform_data = NULL;
339 int rc = 0;
340
341 /* Make sure it has a compatible property */
342 if (strict && (!of_get_property(bus, "compatible", NULL))) {
343 pr_debug("%s() - skipping %s, no compatible prop\n",
344 __func__, bus->full_name);
345 return 0;
346 }
347
348 auxdata = of_dev_lookup(lookup, bus);
349 if (auxdata) {
350 bus_id = auxdata->name;
351 platform_data = auxdata->platform_data;
352 }
353
354 if (of_device_is_compatible(bus, "arm,primecell")) {
355 /*
356 * Don't return an error here to keep compatibility with older
357 * device tree files.
358 */
359 of_amba_device_create(bus, bus_id, platform_data, parent);
360 return 0;
361 }
362
363 dev = of_platform_device_create_pdata(bus, bus_id, platform_data, parent);
364 if (!dev || !of_match_node(matches, bus))
365 return 0;
366
367 for_each_child_of_node(bus, child) {
368 pr_debug(" create child: %s\n", child->full_name);
369 rc = of_platform_bus_create(child, matches, lookup, &dev->dev, strict);
370 if (rc) {
371 of_node_put(child);
372 break;
373 }
374 }
375 of_node_set_flag(bus, OF_POPULATED_BUS);
376 return rc;
377}
378
379/**
380 * of_platform_bus_probe() - Probe the device-tree for platform buses
381 * @root: parent of the first level to probe or NULL for the root of the tree
382 * @matches: match table for bus nodes
383 * @parent: parent to hook devices from, NULL for toplevel
384 *
385 * Note that children of the provided root are not instantiated as devices
386 * unless the specified root itself matches the bus list and is not NULL.
387 */
388int of_platform_bus_probe(struct device_node *root,
389 const struct of_device_id *matches,
390 struct device *parent)
391{
392 struct device_node *child;
393 int rc = 0;
394
395 root = root ? of_node_get(root) : of_find_node_by_path("/");
396 if (!root)
397 return -EINVAL;
398
399 pr_debug("of_platform_bus_probe()\n");
400 pr_debug(" starting at: %s\n", root->full_name);
401
402 /* Do a self check of bus type, if there's a match, create children */
403 if (of_match_node(matches, root)) {
404 rc = of_platform_bus_create(root, matches, NULL, parent, false);
405 } else for_each_child_of_node(root, child) {
406 if (!of_match_node(matches, child))
407 continue;
408 rc = of_platform_bus_create(child, matches, NULL, parent, false);
409 if (rc) {
410 of_node_put(child);
411 break;
412 }
413 }
414
415 of_node_put(root);
416 return rc;
417}
418EXPORT_SYMBOL(of_platform_bus_probe);
419
420/**
421 * of_platform_populate() - Populate platform_devices from device tree data
422 * @root: parent of the first level to probe or NULL for the root of the tree
423 * @matches: match table, NULL to use the default
424 * @lookup: auxdata table for matching id and platform_data with device nodes
425 * @parent: parent to hook devices from, NULL for toplevel
426 *
427 * Similar to of_platform_bus_probe(), this function walks the device tree
428 * and creates devices from nodes. It differs in that it follows the modern
429 * convention of requiring all device nodes to have a 'compatible' property,
430 * and it is suitable for creating devices which are children of the root
431 * node (of_platform_bus_probe will only create children of the root which
432 * are selected by the @matches argument).
433 *
434 * New board support should be using this function instead of
435 * of_platform_bus_probe().
436 *
437 * Returns 0 on success, < 0 on failure.
438 */
439int of_platform_populate(struct device_node *root,
440 const struct of_device_id *matches,
441 const struct of_dev_auxdata *lookup,
442 struct device *parent)
443{
444 struct device_node *child;
445 int rc = 0;
446
447 root = root ? of_node_get(root) : of_find_node_by_path("/");
448 if (!root)
449 return -EINVAL;
450
451 for_each_child_of_node(root, child) {
452 rc = of_platform_bus_create(child, matches, lookup, parent, true);
453 if (rc) {
454 of_node_put(child);
455 break;
456 }
457 }
458 of_node_set_flag(root, OF_POPULATED_BUS);
459
460 of_node_put(root);
461 return rc;
462}
463EXPORT_SYMBOL_GPL(of_platform_populate);
464
465int of_platform_default_populate(struct device_node *root,
466 const struct of_dev_auxdata *lookup,
467 struct device *parent)
468{
469 return of_platform_populate(root, of_default_bus_match_table, lookup,
470 parent);
471}
472EXPORT_SYMBOL_GPL(of_platform_default_populate);
473
474static int of_platform_device_destroy(struct device *dev, void *data)
475{
476 /* Do not touch devices not populated from the device tree */
477 if (!dev->of_node || !of_node_check_flag(dev->of_node, OF_POPULATED))
478 return 0;
479
480 /* Recurse for any nodes that were treated as busses */
481 if (of_node_check_flag(dev->of_node, OF_POPULATED_BUS))
482 device_for_each_child(dev, NULL, of_platform_device_destroy);
483
484 if (dev->bus == &platform_bus_type)
485 platform_device_unregister(to_platform_device(dev));
486#ifdef CONFIG_ARM_AMBA
487 else if (dev->bus == &amba_bustype)
488 amba_device_unregister(to_amba_device(dev));
489#endif
490
491 of_dma_deconfigure(dev);
492 of_node_clear_flag(dev->of_node, OF_POPULATED);
493 of_node_clear_flag(dev->of_node, OF_POPULATED_BUS);
494 return 0;
495}
496
497/**
498 * of_platform_depopulate() - Remove devices populated from device tree
499 * @parent: device which children will be removed
500 *
501 * Complementary to of_platform_populate(), this function removes children
502 * of the given device (and, recurrently, their children) that have been
503 * created from their respective device tree nodes (and only those,
504 * leaving others - eg. manually created - unharmed).
505 *
506 * Returns 0 when all children devices have been removed or
507 * -EBUSY when some children remained.
508 */
509void of_platform_depopulate(struct device *parent)
510{
511 if (parent->of_node && of_node_check_flag(parent->of_node, OF_POPULATED_BUS)) {
512 device_for_each_child(parent, NULL, of_platform_device_destroy);
513 of_node_clear_flag(parent->of_node, OF_POPULATED_BUS);
514 }
515}
516EXPORT_SYMBOL_GPL(of_platform_depopulate);
517
518#ifdef CONFIG_OF_DYNAMIC
519static int of_platform_notify(struct notifier_block *nb,
520 unsigned long action, void *arg)
521{
522 struct of_reconfig_data *rd = arg;
523 struct platform_device *pdev_parent, *pdev;
524 bool children_left;
525
526 switch (of_reconfig_get_state_change(action, rd)) {
527 case OF_RECONFIG_CHANGE_ADD:
528 /* verify that the parent is a bus */
529 if (!of_node_check_flag(rd->dn->parent, OF_POPULATED_BUS))
530 return NOTIFY_OK; /* not for us */
531
532 /* already populated? (driver using of_populate manually) */
533 if (of_node_check_flag(rd->dn, OF_POPULATED))
534 return NOTIFY_OK;
535
536 /* pdev_parent may be NULL when no bus platform device */
537 pdev_parent = of_find_device_by_node(rd->dn->parent);
538 pdev = of_platform_device_create(rd->dn, NULL,
539 pdev_parent ? &pdev_parent->dev : NULL);
540 of_dev_put(pdev_parent);
541
542 if (pdev == NULL) {
543 pr_err("%s: failed to create for '%s'\n",
544 __func__, rd->dn->full_name);
545 /* of_platform_device_create tosses the error code */
546 return notifier_from_errno(-EINVAL);
547 }
548 break;
549
550 case OF_RECONFIG_CHANGE_REMOVE:
551
552 /* already depopulated? */
553 if (!of_node_check_flag(rd->dn, OF_POPULATED))
554 return NOTIFY_OK;
555
556 /* find our device by node */
557 pdev = of_find_device_by_node(rd->dn);
558 if (pdev == NULL)
559 return NOTIFY_OK; /* no? not meant for us */
560
561 /* unregister takes one ref away */
562 of_platform_device_destroy(&pdev->dev, &children_left);
563
564 /* and put the reference of the find */
565 of_dev_put(pdev);
566 break;
567 }
568
569 return NOTIFY_OK;
570}
571
572static struct notifier_block platform_of_notifier = {
573 .notifier_call = of_platform_notify,
574};
575
576void of_platform_register_reconfig_notifier(void)
577{
578 WARN_ON(of_reconfig_notifier_register(&platform_of_notifier));
579}
580#endif /* CONFIG_OF_DYNAMIC */
581
582#endif /* CONFIG_OF_ADDRESS */