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
314	if (!lookup)
315		return NULL;
316
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;
326	}
327
328	return NULL;
329}
330
331/**
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
338 *
339 * Creates a platform_device for the provided device_node, and optionally
340 * recursively create devices for all the child nodes.
341 */
342static 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)
346{
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;
353
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;
359	}
360
361	auxdata = of_dev_lookup(lookup, bus);
362	if (auxdata) {
363		bus_id = auxdata->name;
364		platform_data = auxdata->platform_data;
365	}
366
367	if (of_device_is_compatible(bus, "arm,primecell")) {
368		of_amba_device_create(bus, bus_id, platform_data, parent);
369		return 0;
370	}
371
372	dev = of_platform_device_create_pdata(bus, bus_id, platform_data, parent);
373	if (!dev || !of_match_node(matches, bus))
374		return 0;
375
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;
382		}
383	}
384	return rc;
385}
386
387/**
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
392 *
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.
395 */
396int of_platform_bus_probe(struct device_node *root,
397			  const struct of_device_id *matches,
398			  struct device *parent)
399{
400	struct device_node *child;
401	int rc = 0;
402
403	root = root ? of_node_get(root) : of_find_node_by_path("/");
404	if (!root)
405		return -EINVAL;
406
407	pr_debug("of_platform_bus_probe()\n");
408	pr_debug(" starting at: %s\n", root->full_name);
409
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;
419	}
420
421	of_node_put(root);
422	return rc;
423}
424EXPORT_SYMBOL(of_platform_bus_probe);
425
426/**
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
431 *
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).
438 *
439 * New board support should be using this function instead of
440 * of_platform_bus_probe().
441 *
442 * Returns 0 on success, < 0 on failure.
443 */
444int 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)
448{
449	struct device_node *child;
450	int rc = 0;
451
452	root = root ? of_node_get(root) : of_find_node_by_path("/");
453	if (!root)
454		return -EINVAL;
455
456	for_each_child_of_node(root, child) {
457		rc = of_platform_bus_create(child, matches, lookup, parent, true);
458		if (rc)
459			break;
460	}
461
462	of_node_put(root);
463	return rc;
464}
465#endif /* !CONFIG_SPARC */
466