Revert "ARM: tegra: tegratab: dummy change"
[linux-2.6.git] / drivers / acpi / glue.c
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(x...) printk(PREFIX x)
22 #else
23 #define DBG(x...) do { } while(0)
24 #endif
25 static LIST_HEAD(bus_type_list);
26 static DECLARE_RWSEM(bus_type_sem);
27
28 int register_acpi_bus_type(struct acpi_bus_type *type)
29 {
30         if (acpi_disabled)
31                 return -ENODEV;
32         if (type && type->bus && type->find_device) {
33                 down_write(&bus_type_sem);
34                 list_add_tail(&type->list, &bus_type_list);
35                 up_write(&bus_type_sem);
36                 printk(KERN_INFO PREFIX "bus type %s registered\n",
37                        type->bus->name);
38                 return 0;
39         }
40         return -ENODEV;
41 }
42
43 int unregister_acpi_bus_type(struct acpi_bus_type *type)
44 {
45         if (acpi_disabled)
46                 return 0;
47         if (type) {
48                 down_write(&bus_type_sem);
49                 list_del_init(&type->list);
50                 up_write(&bus_type_sem);
51                 printk(KERN_INFO PREFIX "ACPI bus type %s unregistered\n",
52                        type->bus->name);
53                 return 0;
54         }
55         return -ENODEV;
56 }
57
58 static struct acpi_bus_type *acpi_get_bus_type(struct bus_type *type)
59 {
60         struct acpi_bus_type *tmp, *ret = NULL;
61
62         down_read(&bus_type_sem);
63         list_for_each_entry(tmp, &bus_type_list, list) {
64                 if (tmp->bus == type) {
65                         ret = tmp;
66                         break;
67                 }
68         }
69         up_read(&bus_type_sem);
70         return ret;
71 }
72
73 static int acpi_find_bridge_device(struct device *dev, acpi_handle * handle)
74 {
75         struct acpi_bus_type *tmp;
76         int ret = -ENODEV;
77
78         down_read(&bus_type_sem);
79         list_for_each_entry(tmp, &bus_type_list, list) {
80                 if (tmp->find_bridge && !tmp->find_bridge(dev, handle)) {
81                         ret = 0;
82                         break;
83                 }
84         }
85         up_read(&bus_type_sem);
86         return ret;
87 }
88
89 /* Get device's handler per its address under its parent */
90 struct acpi_find_child {
91         acpi_handle handle;
92         u64 address;
93 };
94
95 static acpi_status
96 do_acpi_find_child(acpi_handle handle, u32 lvl, void *context, void **rv)
97 {
98         acpi_status status;
99         struct acpi_device_info *info;
100         struct acpi_find_child *find = context;
101
102         status = acpi_get_object_info(handle, &info);
103         if (ACPI_SUCCESS(status)) {
104                 if ((info->address == find->address)
105                         && (info->valid & ACPI_VALID_ADR))
106                         find->handle = handle;
107                 kfree(info);
108         }
109         return AE_OK;
110 }
111
112 acpi_handle acpi_get_child(acpi_handle parent, u64 address)
113 {
114         struct acpi_find_child find = { NULL, address };
115
116         if (!parent)
117                 return NULL;
118         acpi_walk_namespace(ACPI_TYPE_DEVICE, parent,
119                             1, do_acpi_find_child, NULL, &find, NULL);
120         return find.handle;
121 }
122
123 EXPORT_SYMBOL(acpi_get_child);
124
125 /* Link ACPI devices with physical devices */
126 static void acpi_glue_data_handler(acpi_handle handle,
127                                    void *context)
128 {
129         /* we provide an empty handler */
130 }
131
132 /* Note: a success call will increase reference count by one */
133 struct device *acpi_get_physical_device(acpi_handle handle)
134 {
135         acpi_status status;
136         struct device *dev;
137
138         status = acpi_get_data(handle, acpi_glue_data_handler, (void **)&dev);
139         if (ACPI_SUCCESS(status))
140                 return get_device(dev);
141         return NULL;
142 }
143
144 EXPORT_SYMBOL(acpi_get_physical_device);
145
146 static int acpi_bind_one(struct device *dev, acpi_handle handle)
147 {
148         struct acpi_device *acpi_dev;
149         acpi_status status;
150
151         if (dev->archdata.acpi_handle) {
152                 dev_warn(dev, "Drivers changed 'acpi_handle'\n");
153                 return -EINVAL;
154         }
155         get_device(dev);
156         status = acpi_attach_data(handle, acpi_glue_data_handler, dev);
157         if (ACPI_FAILURE(status)) {
158                 put_device(dev);
159                 return -EINVAL;
160         }
161         dev->archdata.acpi_handle = handle;
162
163         status = acpi_bus_get_device(handle, &acpi_dev);
164         if (!ACPI_FAILURE(status)) {
165                 int ret;
166
167                 ret = sysfs_create_link(&dev->kobj, &acpi_dev->dev.kobj,
168                                 "firmware_node");
169                 ret = sysfs_create_link(&acpi_dev->dev.kobj, &dev->kobj,
170                                 "physical_node");
171                 if (acpi_dev->wakeup.flags.valid)
172                         device_set_wakeup_capable(dev, true);
173         }
174
175         return 0;
176 }
177
178 static int acpi_unbind_one(struct device *dev)
179 {
180         if (!dev->archdata.acpi_handle)
181                 return 0;
182         if (dev == acpi_get_physical_device(dev->archdata.acpi_handle)) {
183                 struct acpi_device *acpi_dev;
184
185                 /* acpi_get_physical_device increase refcnt by one */
186                 put_device(dev);
187
188                 if (!acpi_bus_get_device(dev->archdata.acpi_handle,
189                                         &acpi_dev)) {
190                         sysfs_remove_link(&dev->kobj, "firmware_node");
191                         sysfs_remove_link(&acpi_dev->dev.kobj, "physical_node");
192                 }
193
194                 acpi_detach_data(dev->archdata.acpi_handle,
195                                  acpi_glue_data_handler);
196                 dev->archdata.acpi_handle = NULL;
197                 /* acpi_bind_one increase refcnt by one */
198                 put_device(dev);
199         } else {
200                 dev_err(dev, "Oops, 'acpi_handle' corrupt\n");
201         }
202         return 0;
203 }
204
205 static int acpi_platform_notify(struct device *dev)
206 {
207         struct acpi_bus_type *type;
208         acpi_handle handle;
209         int ret = -EINVAL;
210
211         if (!dev->bus || !dev->parent) {
212                 /* bridge devices genernally haven't bus or parent */
213                 ret = acpi_find_bridge_device(dev, &handle);
214                 goto end;
215         }
216         type = acpi_get_bus_type(dev->bus);
217         if (!type) {
218                 DBG("No ACPI bus support for %s\n", dev_name(dev));
219                 ret = -EINVAL;
220                 goto end;
221         }
222         if ((ret = type->find_device(dev, &handle)) != 0)
223                 DBG("Can't get handler for %s\n", dev_name(dev));
224       end:
225         if (!ret)
226                 acpi_bind_one(dev, handle);
227
228 #if ACPI_GLUE_DEBUG
229         if (!ret) {
230                 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
231
232                 acpi_get_name(dev->archdata.acpi_handle,
233                               ACPI_FULL_PATHNAME, &buffer);
234                 DBG("Device %s -> %s\n", dev_name(dev), (char *)buffer.pointer);
235                 kfree(buffer.pointer);
236         } else
237                 DBG("Device %s -> No ACPI support\n", dev_name(dev));
238 #endif
239
240         return ret;
241 }
242
243 static int acpi_platform_notify_remove(struct device *dev)
244 {
245         acpi_unbind_one(dev);
246         return 0;
247 }
248
249 int __init init_acpi_device_notify(void)
250 {
251         if (platform_notify || platform_notify_remove) {
252                 printk(KERN_ERR PREFIX "Can't use platform_notify\n");
253                 return 0;
254         }
255         platform_notify = acpi_platform_notify;
256         platform_notify_remove = acpi_platform_notify_remove;
257         return 0;
258 }