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Viewing changes to drivers/acpi/glue.c

  • Committer: Package Import Robot
  • Author(s): Alessio Igor Bogani
  • Date: 2011-10-26 11:13:05 UTC
  • Revision ID: package-import@ubuntu.com-20111026111305-tz023xykf0i6eosh
Tags: upstream-3.2.0
Import upstream version 3.2.0

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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/export.h>
 
10
#include <linux/init.h>
 
11
#include <linux/list.h>
 
12
#include <linux/device.h>
 
13
#include <linux/slab.h>
 
14
#include <linux/rwsem.h>
 
15
#include <linux/acpi.h>
 
16
 
 
17
#include "internal.h"
 
18
 
 
19
#define ACPI_GLUE_DEBUG 0
 
20
#if ACPI_GLUE_DEBUG
 
21
#define DBG(x...) printk(PREFIX x)
 
22
#else
 
23
#define DBG(x...) do { } while(0)
 
24
#endif
 
25
static LIST_HEAD(bus_type_list);
 
26
static DECLARE_RWSEM(bus_type_sem);
 
27
 
 
28
int register_acpi_bus_type(struct acpi_bus_type *type)
 
29
{
 
30
        if (acpi_disabled)
 
31
                return -ENODEV;
 
32
        if (type && type->bus && type->find_device) {
 
33
                down_write(&bus_type_sem);
 
34
                list_add_tail(&type->list, &bus_type_list);
 
35
                up_write(&bus_type_sem);
 
36
                printk(KERN_INFO PREFIX "bus type %s registered\n",
 
37
                       type->bus->name);
 
38
                return 0;
 
39
        }
 
40
        return -ENODEV;
 
41
}
 
42
 
 
43
int unregister_acpi_bus_type(struct acpi_bus_type *type)
 
44
{
 
45
        if (acpi_disabled)
 
46
                return 0;
 
47
        if (type) {
 
48
                down_write(&bus_type_sem);
 
49
                list_del_init(&type->list);
 
50
                up_write(&bus_type_sem);
 
51
                printk(KERN_INFO PREFIX "ACPI bus type %s unregistered\n",
 
52
                       type->bus->name);
 
53
                return 0;
 
54
        }
 
55
        return -ENODEV;
 
56
}
 
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 device's handler per its address under its parent */
 
90
struct acpi_find_child {
 
91
        acpi_handle handle;
 
92
        u64 address;
 
93
};
 
94
 
 
95
static acpi_status
 
96
do_acpi_find_child(acpi_handle handle, u32 lvl, void *context, void **rv)
 
97
{
 
98
        acpi_status status;
 
99
        struct acpi_device_info *info;
 
100
        struct acpi_find_child *find = context;
 
101
 
 
102
        status = acpi_get_object_info(handle, &info);
 
103
        if (ACPI_SUCCESS(status)) {
 
104
                if ((info->address == find->address)
 
105
                        && (info->valid & ACPI_VALID_ADR))
 
106
                        find->handle = handle;
 
107
                kfree(info);
 
108
        }
 
109
        return AE_OK;
 
110
}
 
111
 
 
112
acpi_handle acpi_get_child(acpi_handle parent, u64 address)
 
113
{
 
114
        struct acpi_find_child find = { NULL, address };
 
115
 
 
116
        if (!parent)
 
117
                return NULL;
 
118
        acpi_walk_namespace(ACPI_TYPE_DEVICE, parent,
 
119
                            1, do_acpi_find_child, NULL, &find, NULL);
 
120
        return find.handle;
 
121
}
 
122
 
 
123
EXPORT_SYMBOL(acpi_get_child);
 
124
 
 
125
/* Link ACPI devices with physical devices */
 
126
static void acpi_glue_data_handler(acpi_handle handle,
 
127
                                   void *context)
 
128
{
 
129
        /* we provide an empty handler */
 
130
}
 
131
 
 
132
/* Note: a success call will increase reference count by one */
 
133
struct device *acpi_get_physical_device(acpi_handle handle)
 
134
{
 
135
        acpi_status status;
 
136
        struct device *dev;
 
137
 
 
138
        status = acpi_get_data(handle, acpi_glue_data_handler, (void **)&dev);
 
139
        if (ACPI_SUCCESS(status))
 
140
                return get_device(dev);
 
141
        return NULL;
 
142
}
 
143
 
 
144
EXPORT_SYMBOL(acpi_get_physical_device);
 
145
 
 
146
static int acpi_bind_one(struct device *dev, acpi_handle handle)
 
147
{
 
148
        struct acpi_device *acpi_dev;
 
149
        acpi_status status;
 
150
 
 
151
        if (dev->archdata.acpi_handle) {
 
152
                dev_warn(dev, "Drivers changed 'acpi_handle'\n");
 
153
                return -EINVAL;
 
154
        }
 
155
        get_device(dev);
 
156
        status = acpi_attach_data(handle, acpi_glue_data_handler, dev);
 
157
        if (ACPI_FAILURE(status)) {
 
158
                put_device(dev);
 
159
                return -EINVAL;
 
160
        }
 
161
        dev->archdata.acpi_handle = handle;
 
162
 
 
163
        status = acpi_bus_get_device(handle, &acpi_dev);
 
164
        if (!ACPI_FAILURE(status)) {
 
165
                int ret;
 
166
 
 
167
                ret = sysfs_create_link(&dev->kobj, &acpi_dev->dev.kobj,
 
168
                                "firmware_node");
 
169
                ret = sysfs_create_link(&acpi_dev->dev.kobj, &dev->kobj,
 
170
                                "physical_node");
 
171
                if (acpi_dev->wakeup.flags.valid)
 
172
                        device_set_wakeup_capable(dev, true);
 
173
        }
 
174
 
 
175
        return 0;
 
176
}
 
177
 
 
178
static int acpi_unbind_one(struct device *dev)
 
179
{
 
180
        if (!dev->archdata.acpi_handle)
 
181
                return 0;
 
182
        if (dev == acpi_get_physical_device(dev->archdata.acpi_handle)) {
 
183
                struct acpi_device *acpi_dev;
 
184
 
 
185
                /* acpi_get_physical_device increase refcnt by one */
 
186
                put_device(dev);
 
187
 
 
188
                if (!acpi_bus_get_device(dev->archdata.acpi_handle,
 
189
                                        &acpi_dev)) {
 
190
                        sysfs_remove_link(&dev->kobj, "firmware_node");
 
191
                        sysfs_remove_link(&acpi_dev->dev.kobj, "physical_node");
 
192
                }
 
193
 
 
194
                acpi_detach_data(dev->archdata.acpi_handle,
 
195
                                 acpi_glue_data_handler);
 
196
                dev->archdata.acpi_handle = NULL;
 
197
                /* acpi_bind_one increase refcnt by one */
 
198
                put_device(dev);
 
199
        } else {
 
200
                dev_err(dev, "Oops, 'acpi_handle' corrupt\n");
 
201
        }
 
202
        return 0;
 
203
}
 
204
 
 
205
static int acpi_platform_notify(struct device *dev)
 
206
{
 
207
        struct acpi_bus_type *type;
 
208
        acpi_handle handle;
 
209
        int ret = -EINVAL;
 
210
 
 
211
        if (!dev->bus || !dev->parent) {
 
212
                /* bridge devices genernally haven't bus or parent */
 
213
                ret = acpi_find_bridge_device(dev, &handle);
 
214
                goto end;
 
215
        }
 
216
        type = acpi_get_bus_type(dev->bus);
 
217
        if (!type) {
 
218
                DBG("No ACPI bus support for %s\n", dev_name(dev));
 
219
                ret = -EINVAL;
 
220
                goto end;
 
221
        }
 
222
        if ((ret = type->find_device(dev, &handle)) != 0)
 
223
                DBG("Can't get handler for %s\n", dev_name(dev));
 
224
      end:
 
225
        if (!ret)
 
226
                acpi_bind_one(dev, handle);
 
227
 
 
228
#if ACPI_GLUE_DEBUG
 
229
        if (!ret) {
 
230
                struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 
231
 
 
232
                acpi_get_name(dev->archdata.acpi_handle,
 
233
                              ACPI_FULL_PATHNAME, &buffer);
 
234
                DBG("Device %s -> %s\n", dev_name(dev), (char *)buffer.pointer);
 
235
                kfree(buffer.pointer);
 
236
        } else
 
237
                DBG("Device %s -> No ACPI support\n", dev_name(dev));
 
238
#endif
 
239
 
 
240
        return ret;
 
241
}
 
242
 
 
243
static int acpi_platform_notify_remove(struct device *dev)
 
244
{
 
245
        acpi_unbind_one(dev);
 
246
        return 0;
 
247
}
 
248
 
 
249
int __init init_acpi_device_notify(void)
 
250
{
 
251
        if (platform_notify || platform_notify_remove) {
 
252
                printk(KERN_ERR PREFIX "Can't use platform_notify\n");
 
253
                return 0;
 
254
        }
 
255
        platform_notify = acpi_platform_notify;
 
256
        platform_notify_remove = acpi_platform_notify_remove;
 
257
        return 0;
 
258
}