Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/shaggy...
[linux-2.6] / 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 #define ACPI_GLUE_DEBUG 0
16 #if ACPI_GLUE_DEBUG
17 #define DBG(x...) printk(PREFIX x)
18 #else
19 #define DBG(x...) do { } while(0)
20 #endif
21 static LIST_HEAD(bus_type_list);
22 static DECLARE_RWSEM(bus_type_sem);
23
24 int register_acpi_bus_type(struct acpi_bus_type *type)
25 {
26         if (acpi_disabled)
27                 return -ENODEV;
28         if (type && type->bus && type->find_device) {
29                 down_write(&bus_type_sem);
30                 list_add_tail(&type->list, &bus_type_list);
31                 up_write(&bus_type_sem);
32                 printk(KERN_INFO PREFIX "bus type %s registered\n",
33                        type->bus->name);
34                 return 0;
35         }
36         return -ENODEV;
37 }
38
39 int unregister_acpi_bus_type(struct acpi_bus_type *type)
40 {
41         if (acpi_disabled)
42                 return 0;
43         if (type) {
44                 down_write(&bus_type_sem);
45                 list_del_init(&type->list);
46                 up_write(&bus_type_sem);
47                 printk(KERN_INFO PREFIX "ACPI bus type %s unregistered\n",
48                        type->bus->name);
49                 return 0;
50         }
51         return -ENODEV;
52 }
53
54 static struct acpi_bus_type *acpi_get_bus_type(struct bus_type *type)
55 {
56         struct acpi_bus_type *tmp, *ret = NULL;
57
58         down_read(&bus_type_sem);
59         list_for_each_entry(tmp, &bus_type_list, list) {
60                 if (tmp->bus == type) {
61                         ret = tmp;
62                         break;
63                 }
64         }
65         up_read(&bus_type_sem);
66         return ret;
67 }
68
69 static int acpi_find_bridge_device(struct device *dev, acpi_handle * handle)
70 {
71         struct acpi_bus_type *tmp;
72         int ret = -ENODEV;
73
74         down_read(&bus_type_sem);
75         list_for_each_entry(tmp, &bus_type_list, list) {
76                 if (tmp->find_bridge && !tmp->find_bridge(dev, handle)) {
77                         ret = 0;
78                         break;
79                 }
80         }
81         up_read(&bus_type_sem);
82         return ret;
83 }
84
85 /* Get device's handler per its address under its parent */
86 struct acpi_find_child {
87         acpi_handle handle;
88         acpi_integer address;
89 };
90
91 static acpi_status
92 do_acpi_find_child(acpi_handle handle, u32 lvl, void *context, void **rv)
93 {
94         acpi_status status;
95         struct acpi_device_info *info;
96         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
97         struct acpi_find_child *find = context;
98
99         status = acpi_get_object_info(handle, &buffer);
100         if (ACPI_SUCCESS(status)) {
101                 info = buffer.pointer;
102                 if (info->address == find->address)
103                         find->handle = handle;
104                 kfree(buffer.pointer);
105         }
106         return AE_OK;
107 }
108
109 acpi_handle acpi_get_child(acpi_handle parent, acpi_integer 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, &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                                    u32 function, 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 /* ToDo: When a PCI bridge is found, return the PCI device behind the bridge
144  *       This should work in general, but did not on a Lenovo T61 for the
145  *       graphics card. But this must be fixed when the PCI device is
146  *       bound and the kernel device struct is attached to the acpi device
147  * Note: A success call will increase reference count by one
148  *       Do call put_device(dev) on the returned device then
149  */
150 struct device *acpi_get_physical_pci_device(acpi_handle handle)
151 {
152         struct device *dev;
153         long long device_id;
154         acpi_status status;
155
156         status =
157                 acpi_evaluate_integer(handle, "_ADR", NULL, &device_id);
158
159         if (ACPI_FAILURE(status))
160                 return NULL;
161
162         /* We need to attempt to determine whether the _ADR refers to a
163            PCI device or not. There's no terribly good way to do this,
164            so the best we can hope for is to assume that there'll never
165            be a device in the host bridge */
166         if (device_id >= 0x10000) {
167                 /* It looks like a PCI device. Does it exist? */
168                 dev = acpi_get_physical_device(handle);
169         } else {
170                 /* It doesn't look like a PCI device. Does its parent
171                    exist? */
172                 acpi_handle phandle;
173                 if (acpi_get_parent(handle, &phandle))
174                         return NULL;
175                 dev = acpi_get_physical_device(phandle);
176         }
177         if (!dev)
178                 return NULL;
179         return dev;
180 }
181 EXPORT_SYMBOL(acpi_get_physical_pci_device);
182
183 static int acpi_bind_one(struct device *dev, acpi_handle handle)
184 {
185         struct acpi_device *acpi_dev;
186         acpi_status status;
187
188         if (dev->archdata.acpi_handle) {
189                 dev_warn(dev, "Drivers changed 'acpi_handle'\n");
190                 return -EINVAL;
191         }
192         get_device(dev);
193         status = acpi_attach_data(handle, acpi_glue_data_handler, dev);
194         if (ACPI_FAILURE(status)) {
195                 put_device(dev);
196                 return -EINVAL;
197         }
198         dev->archdata.acpi_handle = handle;
199
200         status = acpi_bus_get_device(handle, &acpi_dev);
201         if (!ACPI_FAILURE(status)) {
202                 int ret;
203
204                 ret = sysfs_create_link(&dev->kobj, &acpi_dev->dev.kobj,
205                                 "firmware_node");
206                 ret = sysfs_create_link(&acpi_dev->dev.kobj, &dev->kobj,
207                                 "physical_node");
208                 if (acpi_dev->wakeup.flags.valid) {
209                         device_set_wakeup_capable(dev, true);
210                         device_set_wakeup_enable(dev,
211                                                 acpi_dev->wakeup.state.enabled);
212                 }
213         }
214
215         return 0;
216 }
217
218 static int acpi_unbind_one(struct device *dev)
219 {
220         if (!dev->archdata.acpi_handle)
221                 return 0;
222         if (dev == acpi_get_physical_device(dev->archdata.acpi_handle)) {
223                 struct acpi_device *acpi_dev;
224
225                 /* acpi_get_physical_device increase refcnt by one */
226                 put_device(dev);
227
228                 if (!acpi_bus_get_device(dev->archdata.acpi_handle,
229                                         &acpi_dev)) {
230                         sysfs_remove_link(&dev->kobj, "firmware_node");
231                         sysfs_remove_link(&acpi_dev->dev.kobj, "physical_node");
232                 }
233
234                 acpi_detach_data(dev->archdata.acpi_handle,
235                                  acpi_glue_data_handler);
236                 dev->archdata.acpi_handle = NULL;
237                 /* acpi_bind_one increase refcnt by one */
238                 put_device(dev);
239         } else {
240                 dev_err(dev, "Oops, 'acpi_handle' corrupt\n");
241         }
242         return 0;
243 }
244
245 static int acpi_platform_notify(struct device *dev)
246 {
247         struct acpi_bus_type *type;
248         acpi_handle handle;
249         int ret = -EINVAL;
250
251         if (!dev->bus || !dev->parent) {
252                 /* bridge devices genernally haven't bus or parent */
253                 ret = acpi_find_bridge_device(dev, &handle);
254                 goto end;
255         }
256         type = acpi_get_bus_type(dev->bus);
257         if (!type) {
258                 DBG("No ACPI bus support for %s\n", dev_name(dev));
259                 ret = -EINVAL;
260                 goto end;
261         }
262         if ((ret = type->find_device(dev, &handle)) != 0)
263                 DBG("Can't get handler for %s\n", dev_name(dev));
264       end:
265         if (!ret)
266                 acpi_bind_one(dev, handle);
267
268 #if ACPI_GLUE_DEBUG
269         if (!ret) {
270                 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
271
272                 acpi_get_name(dev->archdata.acpi_handle,
273                               ACPI_FULL_PATHNAME, &buffer);
274                 DBG("Device %s -> %s\n", dev_name(dev), (char *)buffer.pointer);
275                 kfree(buffer.pointer);
276         } else
277                 DBG("Device %s -> No ACPI support\n", dev_name(dev));
278 #endif
279
280         return ret;
281 }
282
283 static int acpi_platform_notify_remove(struct device *dev)
284 {
285         acpi_unbind_one(dev);
286         return 0;
287 }
288
289 static int __init init_acpi_device_notify(void)
290 {
291         if (acpi_disabled)
292                 return 0;
293         if (platform_notify || platform_notify_remove) {
294                 printk(KERN_ERR PREFIX "Can't use platform_notify\n");
295                 return 0;
296         }
297         platform_notify = acpi_platform_notify;
298         platform_notify_remove = acpi_platform_notify_remove;
299         return 0;
300 }
301
302 arch_initcall(init_acpi_device_notify);