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
register_acpi_bus_type(struct acpi_bus_type * type)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
unregister_acpi_bus_type(struct acpi_bus_type * type)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
acpi_get_bus_type(struct bus_type * type)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
acpi_find_bridge_device(struct device * dev,acpi_handle * handle)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
do_acpi_find_child(acpi_handle handle,u32 lvl,void * context,void ** rv)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
acpi_get_child(acpi_handle parent,acpi_integer address)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 */
acpi_glue_data_handler(acpi_handle handle,u32 function,void * context)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 */
acpi_get_physical_device(acpi_handle handle)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 */
acpi_get_physical_pci_device(acpi_handle handle)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
acpi_bind_one(struct device * dev,acpi_handle handle)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
acpi_unbind_one(struct device * dev)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
acpi_platform_notify(struct device * dev)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
acpi_platform_notify_remove(struct device * dev)283 static int acpi_platform_notify_remove(struct device *dev)
284 {
285 acpi_unbind_one(dev);
286 return 0;
287 }
288
init_acpi_device_notify(void)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);
303