ACPI: Remove unnecessary from/to-void* and to-void casts in drivers/acpi
[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 = 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                 find->handle = handle;
193         status = AE_OK;
194       exit:
195         kfree(buffer.pointer);
196         return status;
197 }
198
199 acpi_handle acpi_get_pci_rootbridge_handle(unsigned int seg, unsigned int bus)
200 {
201         struct acpi_find_pci_root find = { seg, bus, NULL };
202
203         acpi_get_devices(PCI_ROOT_HID_STRING, find_pci_rootbridge, &find, NULL);
204         return find.handle;
205 }
206 EXPORT_SYMBOL_GPL(acpi_get_pci_rootbridge_handle);
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 = 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                 kfree(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                 kfree(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);