Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6
[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/init.h>
10 #include <linux/list.h>
11 #include <linux/device.h>
12 #include <linux/rwsem.h>
13 #include <linux/acpi.h>
14
15 #include "internal.h"
16
17 #define ACPI_GLUE_DEBUG 0
18 #if ACPI_GLUE_DEBUG
19 #define DBG(x...) printk(PREFIX x)
20 #else
21 #define DBG(x...) do { } while(0)
22 #endif
23 static LIST_HEAD(bus_type_list);
24 static DECLARE_RWSEM(bus_type_sem);
25
26 int register_acpi_bus_type(struct acpi_bus_type *type)
27 {
28         if (acpi_disabled)
29                 return -ENODEV;
30         if (type && type->bus && type->find_device) {
31                 down_write(&bus_type_sem);
32                 list_add_tail(&type->list, &bus_type_list);
33                 up_write(&bus_type_sem);
34                 printk(KERN_INFO PREFIX "bus type %s registered\n",
35                        type->bus->name);
36                 return 0;
37         }
38         return -ENODEV;
39 }
40
41 int unregister_acpi_bus_type(struct acpi_bus_type *type)
42 {
43         if (acpi_disabled)
44                 return 0;
45         if (type) {
46                 down_write(&bus_type_sem);
47                 list_del_init(&type->list);
48                 up_write(&bus_type_sem);
49                 printk(KERN_INFO PREFIX "ACPI bus type %s unregistered\n",
50                        type->bus->name);
51                 return 0;
52         }
53         return -ENODEV;
54 }
55
56 static struct acpi_bus_type *acpi_get_bus_type(struct bus_type *type)
57 {
58         struct acpi_bus_type *tmp, *ret = NULL;
59
60         down_read(&bus_type_sem);
61         list_for_each_entry(tmp, &bus_type_list, list) {
62                 if (tmp->bus == type) {
63                         ret = tmp;
64                         break;
65                 }
66         }
67         up_read(&bus_type_sem);
68         return ret;
69 }
70
71 static int acpi_find_bridge_device(struct device *dev, acpi_handle * handle)
72 {
73         struct acpi_bus_type *tmp;
74         int ret = -ENODEV;
75
76         down_read(&bus_type_sem);
77         list_for_each_entry(tmp, &bus_type_list, list) {
78                 if (tmp->find_bridge && !tmp->find_bridge(dev, handle)) {
79                         ret = 0;
80                         break;
81                 }
82         }
83         up_read(&bus_type_sem);
84         return ret;
85 }
86
87 /* Get device's handler per its address under its parent */
88 struct acpi_find_child {
89         acpi_handle handle;
90         u64 address;
91 };
92
93 static acpi_status
94 do_acpi_find_child(acpi_handle handle, u32 lvl, void *context, void **rv)
95 {
96         acpi_status status;
97         struct acpi_device_info *info;
98         struct acpi_find_child *find = context;
99
100         status = acpi_get_object_info(handle, &info);
101         if (ACPI_SUCCESS(status)) {
102                 if (info->address == find->address)
103                         find->handle = handle;
104                 kfree(info);
105         }
106         return AE_OK;
107 }
108
109 acpi_handle acpi_get_child(acpi_handle parent, u64 address)
110 {
111         struct acpi_find_child find = { NULL, address };
112
113         if (!parent)
114                 return NULL;
115         acpi_walk_namespace(ACPI_TYPE_DEVICE, parent,
116                             1, do_acpi_find_child, NULL, &find, NULL);
117         return find.handle;
118 }
119
120 EXPORT_SYMBOL(acpi_get_child);
121
122 /* Link ACPI devices with physical devices */
123 static void acpi_glue_data_handler(acpi_handle handle,
124                                    void *context)
125 {
126         /* we provide an empty handler */
127 }
128
129 /* Note: a success call will increase reference count by one */
130 struct device *acpi_get_physical_device(acpi_handle handle)
131 {
132         acpi_status status;
133         struct device *dev;
134
135         status = acpi_get_data(handle, acpi_glue_data_handler, (void **)&dev);
136         if (ACPI_SUCCESS(status))
137                 return get_device(dev);
138         return NULL;
139 }
140
141 EXPORT_SYMBOL(acpi_get_physical_device);
142
143 static int acpi_bind_one(struct device *dev, acpi_handle handle)
144 {
145         struct acpi_device *acpi_dev;
146         acpi_status status;
147
148         if (dev->archdata.acpi_handle) {
149                 dev_warn(dev, "Drivers changed 'acpi_handle'\n");
150                 return -EINVAL;
151         }
152         get_device(dev);
153         status = acpi_attach_data(handle, acpi_glue_data_handler, dev);
154         if (ACPI_FAILURE(status)) {
155                 put_device(dev);
156                 return -EINVAL;
157         }
158         dev->archdata.acpi_handle = handle;
159
160         status = acpi_bus_get_device(handle, &acpi_dev);
161         if (!ACPI_FAILURE(status)) {
162                 int ret;
163
164                 ret = sysfs_create_link(&dev->kobj, &acpi_dev->dev.kobj,
165                                 "firmware_node");
166                 ret = sysfs_create_link(&acpi_dev->dev.kobj, &dev->kobj,
167                                 "physical_node");
168                 if (acpi_dev->wakeup.flags.valid) {
169                         device_set_wakeup_capable(dev, true);
170                         device_set_wakeup_enable(dev,
171                                                 acpi_dev->wakeup.state.enabled);
172                 }
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 }