Pull trivial into test branch
[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 #define ACPI_GLUE_DEBUG 0
16 #if ACPI_GLUE_DEBUG
17 #define DBG(x...) printk(PREFIX x)
18 #else
19 #define DBG(x...)
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 EXPORT_SYMBOL(register_acpi_bus_type);
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 EXPORT_SYMBOL(unregister_acpi_bus_type);
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 PCI root bridge's handle from its segment and bus number */
90 struct acpi_find_pci_root {
91         unsigned int seg;
92         unsigned int bus;
93         acpi_handle handle;
94 };
95
96 static acpi_status
97 do_root_bridge_busnr_callback(struct acpi_resource *resource, void *data)
98 {
99         unsigned long *busnr = (unsigned long *)data;
100         struct acpi_resource_address64 address;
101
102         if (resource->type != ACPI_RESOURCE_TYPE_ADDRESS16 &&
103             resource->type != ACPI_RESOURCE_TYPE_ADDRESS32 &&
104             resource->type != ACPI_RESOURCE_TYPE_ADDRESS64)
105                 return AE_OK;
106
107         acpi_resource_to_address64(resource, &address);
108         if ((address.address_length > 0) &&
109             (address.resource_type == ACPI_BUS_NUMBER_RANGE))
110                 *busnr = address.minimum;
111
112         return AE_OK;
113 }
114
115 static int get_root_bridge_busnr(acpi_handle handle)
116 {
117         acpi_status status;
118         unsigned long bus, bbn;
119         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
120
121         acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
122
123         status = acpi_evaluate_integer(handle, METHOD_NAME__BBN, NULL,
124                                        &bbn);
125         if (status == AE_NOT_FOUND) {
126                 /* Assume bus = 0 */
127                 printk(KERN_INFO PREFIX
128                        "Assume root bridge [%s] bus is 0\n",
129                        (char *)buffer.pointer);
130                 status = AE_OK;
131                 bbn = 0;
132         }
133         if (ACPI_FAILURE(status)) {
134                 bbn = -ENODEV;
135                 goto exit;
136         }
137         if (bbn > 0)
138                 goto exit;
139
140         /* _BBN in some systems return 0 for all root bridges */
141         bus = -1;
142         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
143                                      do_root_bridge_busnr_callback, &bus);
144         /* If _CRS failed, we just use _BBN */
145         if (ACPI_FAILURE(status) || (bus == -1))
146                 goto exit;
147         /* We select _CRS */
148         if (bbn != bus) {
149                 printk(KERN_INFO PREFIX
150                        "_BBN and _CRS returns different value for %s. Select _CRS\n",
151                        (char *)buffer.pointer);
152                 bbn = bus;
153         }
154       exit:
155         kfree(buffer.pointer);
156         return (int)bbn;
157 }
158
159 static acpi_status
160 find_pci_rootbridge(acpi_handle handle, u32 lvl, void *context, void **rv)
161 {
162         struct acpi_find_pci_root *find = (struct acpi_find_pci_root *)context;
163         unsigned long seg, bus;
164         acpi_status status;
165         int tmp;
166         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
167
168         acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
169
170         status = acpi_evaluate_integer(handle, METHOD_NAME__SEG, NULL, &seg);
171         if (status == AE_NOT_FOUND) {
172                 /* Assume seg = 0 */
173                 status = AE_OK;
174                 seg = 0;
175         }
176         if (ACPI_FAILURE(status)) {
177                 status = AE_CTRL_DEPTH;
178                 goto exit;
179         }
180
181         tmp = get_root_bridge_busnr(handle);
182         if (tmp < 0) {
183                 printk(KERN_ERR PREFIX
184                        "Find root bridge failed for %s\n",
185                        (char *)buffer.pointer);
186                 status = AE_CTRL_DEPTH;
187                 goto exit;
188         }
189         bus = tmp;
190
191         if (seg == find->seg && bus == find->bus)
192         {
193                 find->handle = handle;
194                 status = AE_CTRL_TERMINATE;
195         }
196         else
197                 status = AE_OK;
198       exit:
199         kfree(buffer.pointer);
200         return status;
201 }
202
203 acpi_handle acpi_get_pci_rootbridge_handle(unsigned int seg, unsigned int bus)
204 {
205         struct acpi_find_pci_root find = { seg, bus, NULL };
206
207         acpi_get_devices(PCI_ROOT_HID_STRING, find_pci_rootbridge, &find, NULL);
208         return find.handle;
209 }
210 EXPORT_SYMBOL_GPL(acpi_get_pci_rootbridge_handle);
211
212 /* Get device's handler per its address under its parent */
213 struct acpi_find_child {
214         acpi_handle handle;
215         acpi_integer address;
216 };
217
218 static acpi_status
219 do_acpi_find_child(acpi_handle handle, u32 lvl, void *context, void **rv)
220 {
221         acpi_status status;
222         struct acpi_device_info *info;
223         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
224         struct acpi_find_child *find = (struct acpi_find_child *)context;
225
226         status = acpi_get_object_info(handle, &buffer);
227         if (ACPI_SUCCESS(status)) {
228                 info = buffer.pointer;
229                 if (info->address == find->address)
230                         find->handle = handle;
231                 kfree(buffer.pointer);
232         }
233         return AE_OK;
234 }
235
236 acpi_handle acpi_get_child(acpi_handle parent, acpi_integer address)
237 {
238         struct acpi_find_child find = { NULL, address };
239
240         if (!parent)
241                 return NULL;
242         acpi_walk_namespace(ACPI_TYPE_DEVICE, parent,
243                             1, do_acpi_find_child, &find, NULL);
244         return find.handle;
245 }
246
247 EXPORT_SYMBOL(acpi_get_child);
248
249 /* Link ACPI devices with physical devices */
250 static void acpi_glue_data_handler(acpi_handle handle,
251                                    u32 function, void *context)
252 {
253         /* we provide an empty handler */
254 }
255
256 /* Note: a success call will increase reference count by one */
257 struct device *acpi_get_physical_device(acpi_handle handle)
258 {
259         acpi_status status;
260         struct device *dev;
261
262         status = acpi_get_data(handle, acpi_glue_data_handler, (void **)&dev);
263         if (ACPI_SUCCESS(status))
264                 return get_device(dev);
265         return NULL;
266 }
267
268 EXPORT_SYMBOL(acpi_get_physical_device);
269
270 static int acpi_bind_one(struct device *dev, acpi_handle handle)
271 {
272         acpi_status status;
273
274         if (dev->archdata.acpi_handle) {
275                 printk(KERN_WARNING PREFIX
276                        "Drivers changed 'acpi_handle' for %s\n", dev->bus_id);
277                 return -EINVAL;
278         }
279         get_device(dev);
280         status = acpi_attach_data(handle, acpi_glue_data_handler, dev);
281         if (ACPI_FAILURE(status)) {
282                 put_device(dev);
283                 return -EINVAL;
284         }
285         dev->archdata.acpi_handle = handle;
286
287         return 0;
288 }
289
290 static int acpi_unbind_one(struct device *dev)
291 {
292         if (!dev->archdata.acpi_handle)
293                 return 0;
294         if (dev == acpi_get_physical_device(dev->archdata.acpi_handle)) {
295                 /* acpi_get_physical_device increase refcnt by one */
296                 put_device(dev);
297                 acpi_detach_data(dev->archdata.acpi_handle,
298                                  acpi_glue_data_handler);
299                 dev->archdata.acpi_handle = NULL;
300                 /* acpi_bind_one increase refcnt by one */
301                 put_device(dev);
302         } else {
303                 printk(KERN_ERR PREFIX
304                        "Oops, 'acpi_handle' corrupt for %s\n", dev->bus_id);
305         }
306         return 0;
307 }
308
309 static int acpi_platform_notify(struct device *dev)
310 {
311         struct acpi_bus_type *type;
312         acpi_handle handle;
313         int ret = -EINVAL;
314
315         if (!dev->bus || !dev->parent) {
316                 /* bridge devices genernally haven't bus or parent */
317                 ret = acpi_find_bridge_device(dev, &handle);
318                 goto end;
319         }
320         type = acpi_get_bus_type(dev->bus);
321         if (!type) {
322                 DBG("No ACPI bus support for %s\n", dev->bus_id);
323                 ret = -EINVAL;
324                 goto end;
325         }
326         if ((ret = type->find_device(dev, &handle)) != 0)
327                 DBG("Can't get handler for %s\n", dev->bus_id);
328       end:
329         if (!ret)
330                 acpi_bind_one(dev, handle);
331
332 #if ACPI_GLUE_DEBUG
333         if (!ret) {
334                 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
335
336                 acpi_get_name(dev->archdata.acpi_handle,
337                               ACPI_FULL_PATHNAME, &buffer);
338                 DBG("Device %s -> %s\n", dev->bus_id, (char *)buffer.pointer);
339                 kfree(buffer.pointer);
340         } else
341                 DBG("Device %s -> No ACPI support\n", dev->bus_id);
342 #endif
343
344         return ret;
345 }
346
347 static int acpi_platform_notify_remove(struct device *dev)
348 {
349         acpi_unbind_one(dev);
350         return 0;
351 }
352
353 static int __init init_acpi_device_notify(void)
354 {
355         if (acpi_disabled)
356                 return 0;
357         if (platform_notify || platform_notify_remove) {
358                 printk(KERN_ERR PREFIX "Can't use platform_notify\n");
359                 return 0;
360         }
361         platform_notify = acpi_platform_notify;
362         platform_notify_remove = acpi_platform_notify_remove;
363         return 0;
364 }
365
366 arch_initcall(init_acpi_device_notify);