/spare/repo/libata-dev branch 'v2.6.13'
[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...)
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", type->bus->name);
33                 return 0;
34         }
35         return -ENODEV;
36 }
37
38 EXPORT_SYMBOL(register_acpi_bus_type);
39
40 int unregister_acpi_bus_type(struct acpi_bus_type *type)
41 {
42         if (acpi_disabled)
43                 return 0;
44         if (type) {
45                 down_write(&bus_type_sem);
46                 list_del_init(&type->list);
47                 up_write(&bus_type_sem);
48                 printk(KERN_INFO PREFIX "ACPI bus type %s unregistered\n", type->bus->name);
49                 return 0;
50         }
51         return -ENODEV;
52 }
53
54 EXPORT_SYMBOL(unregister_acpi_bus_type);
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 PCI root bridge's handle from its segment and bus number */
88 struct acpi_find_pci_root {
89         unsigned int seg;
90         unsigned int bus;
91         acpi_handle handle;
92 };
93
94 static acpi_status
95 do_root_bridge_busnr_callback(struct acpi_resource *resource, void *data)
96 {
97         int *busnr = (int *)data;
98         struct acpi_resource_address64 address;
99
100         if (resource->id != ACPI_RSTYPE_ADDRESS16 &&
101             resource->id != ACPI_RSTYPE_ADDRESS32 &&
102             resource->id != ACPI_RSTYPE_ADDRESS64)
103                 return AE_OK;
104
105         acpi_resource_to_address64(resource, &address);
106         if ((address.address_length > 0) &&
107             (address.resource_type == ACPI_BUS_NUMBER_RANGE))
108                 *busnr = address.min_address_range;
109
110         return AE_OK;
111 }
112
113 static int get_root_bridge_busnr(acpi_handle handle)
114 {
115         acpi_status status;
116         int bus, bbn;
117         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
118
119         acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
120
121         status = acpi_evaluate_integer(handle, METHOD_NAME__BBN, NULL,
122                                        (unsigned long *)&bbn);
123         if (status == AE_NOT_FOUND) {
124                 /* Assume bus = 0 */
125                 printk(KERN_INFO PREFIX
126                        "Assume root bridge [%s] bus is 0\n",
127                        (char *)buffer.pointer);
128                 status = AE_OK;
129                 bbn = 0;
130         }
131         if (ACPI_FAILURE(status)) {
132                 bbn = -ENODEV;
133                 goto exit;
134         }
135         if (bbn > 0)
136                 goto exit;
137
138         /* _BBN in some systems return 0 for all root bridges */
139         bus = -1;
140         status = acpi_walk_resources(handle, METHOD_NAME__CRS,
141                                      do_root_bridge_busnr_callback, &bus);
142         /* If _CRS failed, we just use _BBN */
143         if (ACPI_FAILURE(status) || (bus == -1))
144                 goto exit;
145         /* We select _CRS */
146         if (bbn != bus) {
147                 printk(KERN_INFO PREFIX
148                        "_BBN and _CRS returns different value for %s. Select _CRS\n",
149                        (char *)buffer.pointer);
150                 bbn = bus;
151         }
152       exit:
153         acpi_os_free(buffer.pointer);
154         return bbn;
155 }
156
157 static acpi_status
158 find_pci_rootbridge(acpi_handle handle, u32 lvl, void *context, void **rv)
159 {
160         struct acpi_find_pci_root *find = (struct acpi_find_pci_root *)context;
161         unsigned long seg, bus;
162         acpi_status status;
163         int tmp;
164         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
165
166         acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
167
168         status = acpi_evaluate_integer(handle, METHOD_NAME__SEG, NULL, &seg);
169         if (status == AE_NOT_FOUND) {
170                 /* Assume seg = 0 */
171                 printk(KERN_INFO PREFIX
172                        "Assume root bridge [%s] segment is 0\n",
173                        (char *)buffer.pointer);
174                 status = AE_OK;
175                 seg = 0;
176         }
177         if (ACPI_FAILURE(status)) {
178                 status = AE_CTRL_DEPTH;
179                 goto exit;
180         }
181
182         tmp = get_root_bridge_busnr(handle);
183         if (tmp < 0) {
184                 printk(KERN_ERR PREFIX
185                        "Find root bridge failed for %s\n",
186                        (char *)buffer.pointer);
187                 status = AE_CTRL_DEPTH;
188                 goto exit;
189         }
190         bus = tmp;
191
192         if (seg == find->seg && bus == find->bus)
193                 find->handle = handle;
194         status = AE_OK;
195       exit:
196         acpi_os_free(buffer.pointer);
197         return status;
198 }
199
200 acpi_handle acpi_get_pci_rootbridge_handle(unsigned int seg, unsigned int bus)
201 {
202         struct acpi_find_pci_root find = { seg, bus, NULL };
203
204         acpi_get_devices(PCI_ROOT_HID_STRING, find_pci_rootbridge, &find, NULL);
205         return find.handle;
206 }
207
208 /* Get device's handler per its address under its parent */
209 struct acpi_find_child {
210         acpi_handle handle;
211         acpi_integer address;
212 };
213
214 static acpi_status
215 do_acpi_find_child(acpi_handle handle, u32 lvl, void *context, void **rv)
216 {
217         acpi_status status;
218         struct acpi_device_info *info;
219         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
220         struct acpi_find_child *find = (struct acpi_find_child *)context;
221
222         status = acpi_get_object_info(handle, &buffer);
223         if (ACPI_SUCCESS(status)) {
224                 info = buffer.pointer;
225                 if (info->address == find->address)
226                         find->handle = handle;
227                 acpi_os_free(buffer.pointer);
228         }
229         return AE_OK;
230 }
231
232 acpi_handle acpi_get_child(acpi_handle parent, acpi_integer address)
233 {
234         struct acpi_find_child find = { NULL, address };
235
236         if (!parent)
237                 return NULL;
238         acpi_walk_namespace(ACPI_TYPE_DEVICE, parent,
239                             1, do_acpi_find_child, &find, NULL);
240         return find.handle;
241 }
242
243 EXPORT_SYMBOL(acpi_get_child);
244
245 /* Link ACPI devices with physical devices */
246 static void acpi_glue_data_handler(acpi_handle handle,
247                                    u32 function, void *context)
248 {
249         /* we provide an empty handler */
250 }
251
252 /* Note: a success call will increase reference count by one */
253 struct device *acpi_get_physical_device(acpi_handle handle)
254 {
255         acpi_status status;
256         struct device *dev;
257
258         status = acpi_get_data(handle, acpi_glue_data_handler, (void **)&dev);
259         if (ACPI_SUCCESS(status))
260                 return get_device(dev);
261         return NULL;
262 }
263
264 EXPORT_SYMBOL(acpi_get_physical_device);
265
266 static int acpi_bind_one(struct device *dev, acpi_handle handle)
267 {
268         acpi_status status;
269
270         if (dev->firmware_data) {
271                 printk(KERN_WARNING PREFIX
272                        "Drivers changed 'firmware_data' for %s\n", dev->bus_id);
273                 return -EINVAL;
274         }
275         get_device(dev);
276         status = acpi_attach_data(handle, acpi_glue_data_handler, dev);
277         if (ACPI_FAILURE(status)) {
278                 put_device(dev);
279                 return -EINVAL;
280         }
281         dev->firmware_data = handle;
282
283         return 0;
284 }
285
286 static int acpi_unbind_one(struct device *dev)
287 {
288         if (!dev->firmware_data)
289                 return 0;
290         if (dev == acpi_get_physical_device(dev->firmware_data)) {
291                 /* acpi_get_physical_device increase refcnt by one */
292                 put_device(dev);
293                 acpi_detach_data(dev->firmware_data, acpi_glue_data_handler);
294                 dev->firmware_data = NULL;
295                 /* acpi_bind_one increase refcnt by one */
296                 put_device(dev);
297         } else {
298                 printk(KERN_ERR PREFIX
299                        "Oops, 'firmware_data' corrupt for %s\n", dev->bus_id);
300         }
301         return 0;
302 }
303
304 static int acpi_platform_notify(struct device *dev)
305 {
306         struct acpi_bus_type *type;
307         acpi_handle handle;
308         int ret = -EINVAL;
309
310         if (!dev->bus || !dev->parent) {
311                 /* bridge devices genernally haven't bus or parent */
312                 ret = acpi_find_bridge_device(dev, &handle);
313                 goto end;
314         }
315         type = acpi_get_bus_type(dev->bus);
316         if (!type) {
317                 DBG("No ACPI bus support for %s\n", dev->bus_id);
318                 ret = -EINVAL;
319                 goto end;
320         }
321         if ((ret = type->find_device(dev, &handle)) != 0)
322                 DBG("Can't get handler for %s\n", dev->bus_id);
323       end:
324         if (!ret)
325                 acpi_bind_one(dev, handle);
326
327 #if ACPI_GLUE_DEBUG
328         if (!ret) {
329                 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
330
331                 acpi_get_name(dev->firmware_data, ACPI_FULL_PATHNAME, &buffer);
332                 DBG("Device %s -> %s\n", dev->bus_id, (char *)buffer.pointer);
333                 acpi_os_free(buffer.pointer);
334         } else
335                 DBG("Device %s -> No ACPI support\n", dev->bus_id);
336 #endif
337
338         return ret;
339 }
340
341 static int acpi_platform_notify_remove(struct device *dev)
342 {
343         acpi_unbind_one(dev);
344         return 0;
345 }
346
347 static int __init init_acpi_device_notify(void)
348 {
349         if (acpi_disabled)
350                 return 0;
351         if (platform_notify || platform_notify_remove) {
352                 printk(KERN_ERR PREFIX "Can't use platform_notify\n");
353                 return 0;
354         }
355         platform_notify = acpi_platform_notify;
356         platform_notify_remove = acpi_platform_notify_remove;
357         return 0;
358 }
359
360 arch_initcall(init_acpi_device_notify);