xref: /linux/drivers/acpi/glue.c (revision ff5599816711d2e67da2d7561fd36ac48debd433)
1 /*
2  * Link physical devices with ACPI devices support
3  *
4  * Copyright (c) 2005 David Shaohua Li <shaohua.li@intel.com>
5  * Copyright (c) 2005 Intel Corp.
6  *
7  * This file is released under the GPLv2.
8  */
9 #include <linux/export.h>
10 #include <linux/init.h>
11 #include <linux/list.h>
12 #include <linux/device.h>
13 #include <linux/slab.h>
14 #include <linux/rwsem.h>
15 #include <linux/acpi.h>
16 
17 #include "internal.h"
18 
19 #define ACPI_GLUE_DEBUG	0
20 #if ACPI_GLUE_DEBUG
21 #define DBG(fmt, ...)						\
22 	printk(KERN_DEBUG PREFIX fmt, ##__VA_ARGS__)
23 #else
24 #define DBG(fmt, ...)						\
25 do {								\
26 	if (0)							\
27 		printk(KERN_DEBUG PREFIX fmt, ##__VA_ARGS__);	\
28 } while (0)
29 #endif
30 static LIST_HEAD(bus_type_list);
31 static DECLARE_RWSEM(bus_type_sem);
32 
33 #define PHYSICAL_NODE_STRING "physical_node"
34 
35 int register_acpi_bus_type(struct acpi_bus_type *type)
36 {
37 	if (acpi_disabled)
38 		return -ENODEV;
39 	if (type && type->match && type->find_device) {
40 		down_write(&bus_type_sem);
41 		list_add_tail(&type->list, &bus_type_list);
42 		up_write(&bus_type_sem);
43 		printk(KERN_INFO PREFIX "bus type %s registered\n", type->name);
44 		return 0;
45 	}
46 	return -ENODEV;
47 }
48 EXPORT_SYMBOL_GPL(register_acpi_bus_type);
49 
50 int unregister_acpi_bus_type(struct acpi_bus_type *type)
51 {
52 	if (acpi_disabled)
53 		return 0;
54 	if (type) {
55 		down_write(&bus_type_sem);
56 		list_del_init(&type->list);
57 		up_write(&bus_type_sem);
58 		printk(KERN_INFO PREFIX "bus type %s unregistered\n",
59 		       type->name);
60 		return 0;
61 	}
62 	return -ENODEV;
63 }
64 EXPORT_SYMBOL_GPL(unregister_acpi_bus_type);
65 
66 static struct acpi_bus_type *acpi_get_bus_type(struct device *dev)
67 {
68 	struct acpi_bus_type *tmp, *ret = NULL;
69 
70 	down_read(&bus_type_sem);
71 	list_for_each_entry(tmp, &bus_type_list, list) {
72 		if (tmp->match(dev)) {
73 			ret = tmp;
74 			break;
75 		}
76 	}
77 	up_read(&bus_type_sem);
78 	return ret;
79 }
80 
81 static acpi_status do_acpi_find_child(acpi_handle handle, u32 lvl_not_used,
82 				      void *addr_p, void **ret_p)
83 {
84 	unsigned long long addr, sta;
85 	acpi_status status;
86 
87 	status = acpi_evaluate_integer(handle, METHOD_NAME__ADR, NULL, &addr);
88 	if (ACPI_SUCCESS(status) && addr == *((u64 *)addr_p)) {
89 		*ret_p = handle;
90 		status = acpi_bus_get_status_handle(handle, &sta);
91 		if (ACPI_SUCCESS(status) && (sta & ACPI_STA_DEVICE_ENABLED))
92 			return AE_CTRL_TERMINATE;
93 	}
94 	return AE_OK;
95 }
96 
97 acpi_handle acpi_get_child(acpi_handle parent, u64 address)
98 {
99 	void *ret = NULL;
100 
101 	if (!parent)
102 		return NULL;
103 
104 	acpi_walk_namespace(ACPI_TYPE_DEVICE, parent, 1, NULL,
105 			    do_acpi_find_child, &address, &ret);
106 	return (acpi_handle)ret;
107 }
108 EXPORT_SYMBOL(acpi_get_child);
109 
110 int acpi_bind_one(struct device *dev, acpi_handle handle)
111 {
112 	struct acpi_device *acpi_dev;
113 	acpi_status status;
114 	struct acpi_device_physical_node *physical_node, *pn;
115 	char physical_node_name[sizeof(PHYSICAL_NODE_STRING) + 2];
116 	int retval = -EINVAL;
117 
118 	if (ACPI_HANDLE(dev)) {
119 		if (handle) {
120 			dev_warn(dev, "ACPI handle is already set\n");
121 			return -EINVAL;
122 		} else {
123 			handle = ACPI_HANDLE(dev);
124 		}
125 	}
126 	if (!handle)
127 		return -EINVAL;
128 
129 	get_device(dev);
130 	status = acpi_bus_get_device(handle, &acpi_dev);
131 	if (ACPI_FAILURE(status))
132 		goto err;
133 
134 	physical_node = kzalloc(sizeof(*physical_node), GFP_KERNEL);
135 	if (!physical_node) {
136 		retval = -ENOMEM;
137 		goto err;
138 	}
139 
140 	mutex_lock(&acpi_dev->physical_node_lock);
141 
142 	/* Sanity check. */
143 	list_for_each_entry(pn, &acpi_dev->physical_node_list, node)
144 		if (pn->dev == dev) {
145 			dev_warn(dev, "Already associated with ACPI node\n");
146 			goto err_free;
147 		}
148 
149 	/* allocate physical node id according to physical_node_id_bitmap */
150 	physical_node->node_id =
151 		find_first_zero_bit(acpi_dev->physical_node_id_bitmap,
152 		ACPI_MAX_PHYSICAL_NODE);
153 	if (physical_node->node_id >= ACPI_MAX_PHYSICAL_NODE) {
154 		retval = -ENOSPC;
155 		goto err_free;
156 	}
157 
158 	set_bit(physical_node->node_id, acpi_dev->physical_node_id_bitmap);
159 	physical_node->dev = dev;
160 	list_add_tail(&physical_node->node, &acpi_dev->physical_node_list);
161 	acpi_dev->physical_node_count++;
162 
163 	mutex_unlock(&acpi_dev->physical_node_lock);
164 
165 	if (!ACPI_HANDLE(dev))
166 		ACPI_HANDLE_SET(dev, acpi_dev->handle);
167 
168 	if (!physical_node->node_id)
169 		strcpy(physical_node_name, PHYSICAL_NODE_STRING);
170 	else
171 		sprintf(physical_node_name,
172 			"physical_node%d", physical_node->node_id);
173 	retval = sysfs_create_link(&acpi_dev->dev.kobj, &dev->kobj,
174 			physical_node_name);
175 	retval = sysfs_create_link(&dev->kobj, &acpi_dev->dev.kobj,
176 		"firmware_node");
177 
178 	if (acpi_dev->wakeup.flags.valid)
179 		device_set_wakeup_capable(dev, true);
180 
181 	return 0;
182 
183  err:
184 	ACPI_HANDLE_SET(dev, NULL);
185 	put_device(dev);
186 	return retval;
187 
188  err_free:
189 	mutex_unlock(&acpi_dev->physical_node_lock);
190 	kfree(physical_node);
191 	goto err;
192 }
193 EXPORT_SYMBOL_GPL(acpi_bind_one);
194 
195 int acpi_unbind_one(struct device *dev)
196 {
197 	struct acpi_device_physical_node *entry;
198 	struct acpi_device *acpi_dev;
199 	acpi_status status;
200 	struct list_head *node, *next;
201 
202 	if (!ACPI_HANDLE(dev))
203 		return 0;
204 
205 	status = acpi_bus_get_device(ACPI_HANDLE(dev), &acpi_dev);
206 	if (ACPI_FAILURE(status))
207 		goto err;
208 
209 	mutex_lock(&acpi_dev->physical_node_lock);
210 	list_for_each_safe(node, next, &acpi_dev->physical_node_list) {
211 		char physical_node_name[sizeof(PHYSICAL_NODE_STRING) + 2];
212 
213 		entry = list_entry(node, struct acpi_device_physical_node,
214 			node);
215 		if (entry->dev != dev)
216 			continue;
217 
218 		list_del(node);
219 		clear_bit(entry->node_id, acpi_dev->physical_node_id_bitmap);
220 
221 		acpi_dev->physical_node_count--;
222 
223 		if (!entry->node_id)
224 			strcpy(physical_node_name, PHYSICAL_NODE_STRING);
225 		else
226 			sprintf(physical_node_name,
227 				"physical_node%d", entry->node_id);
228 
229 		sysfs_remove_link(&acpi_dev->dev.kobj, physical_node_name);
230 		sysfs_remove_link(&dev->kobj, "firmware_node");
231 		ACPI_HANDLE_SET(dev, NULL);
232 		/* acpi_bind_one increase refcnt by one */
233 		put_device(dev);
234 		kfree(entry);
235 	}
236 	mutex_unlock(&acpi_dev->physical_node_lock);
237 
238 	return 0;
239 
240 err:
241 	dev_err(dev, "Oops, 'acpi_handle' corrupt\n");
242 	return -EINVAL;
243 }
244 EXPORT_SYMBOL_GPL(acpi_unbind_one);
245 
246 static int acpi_platform_notify(struct device *dev)
247 {
248 	struct acpi_bus_type *type = acpi_get_bus_type(dev);
249 	acpi_handle handle;
250 	int ret;
251 
252 	ret = acpi_bind_one(dev, NULL);
253 	if (ret && type) {
254 		ret = type->find_device(dev, &handle);
255 		if (ret) {
256 			DBG("Unable to get handle for %s\n", dev_name(dev));
257 			goto out;
258 		}
259 		ret = acpi_bind_one(dev, handle);
260 		if (ret)
261 			goto out;
262 	}
263 
264 	if (type && type->setup)
265 		type->setup(dev);
266 
267  out:
268 #if ACPI_GLUE_DEBUG
269 	if (!ret) {
270 		struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
271 
272 		acpi_get_name(ACPI_HANDLE(dev), ACPI_FULL_PATHNAME, &buffer);
273 		DBG("Device %s -> %s\n", dev_name(dev), (char *)buffer.pointer);
274 		kfree(buffer.pointer);
275 	} else
276 		DBG("Device %s -> No ACPI support\n", dev_name(dev));
277 #endif
278 
279 	return ret;
280 }
281 
282 static int acpi_platform_notify_remove(struct device *dev)
283 {
284 	struct acpi_bus_type *type;
285 
286 	type = acpi_get_bus_type(dev);
287 	if (type && type->cleanup)
288 		type->cleanup(dev);
289 
290 	acpi_unbind_one(dev);
291 	return 0;
292 }
293 
294 int __init init_acpi_device_notify(void)
295 {
296 	if (platform_notify || platform_notify_remove) {
297 		printk(KERN_ERR PREFIX "Can't use platform_notify\n");
298 		return 0;
299 	}
300 	platform_notify = acpi_platform_notify;
301 	platform_notify_remove = acpi_platform_notify_remove;
302 	return 0;
303 }
304