NLM: Fix reclaim races
[linux-2.6/suspend2-2.6.18.git] / drivers / acpi / container.c
blobb69a8cad82b7ca424f3915c1e0eca54e702be08a
1 /*
2 * acpi_container.c - ACPI Generic Container Driver
3 * ($Revision: )
5 * Copyright (C) 2004 Anil S Keshavamurthy (anil.s.keshavamurthy@intel.com)
6 * Copyright (C) 2004 Keiichiro Tokunaga (tokunaga.keiich@jp.fujitsu.com)
7 * Copyright (C) 2004 Motoyuki Ito (motoyuki@soft.fujitsu.com)
8 * Copyright (C) 2004 Intel Corp.
9 * Copyright (C) 2004 FUJITSU LIMITED
11 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
13 * This program is free software; you can redistribute it and/or modify
14 * it under the terms of the GNU General Public License as published by
15 * the Free Software Foundation; either version 2 of the License, or (at
16 * your option) any later version.
18 * This program is distributed in the hope that it will be useful, but
19 * WITHOUT ANY WARRANTY; without even the implied warranty of
20 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
21 * General Public License for more details.
23 * You should have received a copy of the GNU General Public License along
24 * with this program; if not, write to the Free Software Foundation, Inc.,
25 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
27 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
29 #include <linux/kernel.h>
30 #include <linux/module.h>
31 #include <linux/init.h>
32 #include <linux/types.h>
33 #include <linux/acpi.h>
34 #include <acpi/acpi_bus.h>
35 #include <acpi/acpi_drivers.h>
36 #include <acpi/container.h>
38 #define ACPI_CONTAINER_DRIVER_NAME "ACPI container driver"
39 #define ACPI_CONTAINER_DEVICE_NAME "ACPI container device"
40 #define ACPI_CONTAINER_CLASS "container"
42 #define INSTALL_NOTIFY_HANDLER 1
43 #define UNINSTALL_NOTIFY_HANDLER 2
45 #define ACPI_CONTAINER_COMPONENT 0x01000000
46 #define _COMPONENT ACPI_CONTAINER_COMPONENT
47 ACPI_MODULE_NAME("acpi_container")
49 MODULE_AUTHOR("Anil S Keshavamurthy");
50 MODULE_DESCRIPTION(ACPI_CONTAINER_DRIVER_NAME);
51 MODULE_LICENSE("GPL");
53 #define ACPI_STA_PRESENT (0x00000001)
55 static int acpi_container_add(struct acpi_device *device);
56 static int acpi_container_remove(struct acpi_device *device, int type);
58 static struct acpi_driver acpi_container_driver = {
59 .name = ACPI_CONTAINER_DRIVER_NAME,
60 .class = ACPI_CONTAINER_CLASS,
61 .ids = "ACPI0004,PNP0A05,PNP0A06",
62 .ops = {
63 .add = acpi_container_add,
64 .remove = acpi_container_remove,
68 /*******************************************************************/
70 static int is_device_present(acpi_handle handle)
72 acpi_handle temp;
73 acpi_status status;
74 unsigned long sta;
76 ACPI_FUNCTION_TRACE("is_device_present");
78 status = acpi_get_handle(handle, "_STA", &temp);
79 if (ACPI_FAILURE(status))
80 return_VALUE(1); /* _STA not found, assmue device present */
82 status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
83 if (ACPI_FAILURE(status))
84 return_VALUE(0); /* Firmware error */
86 return_VALUE((sta & ACPI_STA_PRESENT) == ACPI_STA_PRESENT);
89 /*******************************************************************/
90 static int acpi_container_add(struct acpi_device *device)
92 struct acpi_container *container;
94 ACPI_FUNCTION_TRACE("acpi_container_add");
96 if (!device) {
97 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "device is NULL\n"));
98 return_VALUE(-EINVAL);
101 container = kmalloc(sizeof(struct acpi_container), GFP_KERNEL);
102 if (!container)
103 return_VALUE(-ENOMEM);
105 memset(container, 0, sizeof(struct acpi_container));
106 container->handle = device->handle;
107 strcpy(acpi_device_name(device), ACPI_CONTAINER_DEVICE_NAME);
108 strcpy(acpi_device_class(device), ACPI_CONTAINER_CLASS);
109 acpi_driver_data(device) = container;
111 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device <%s> bid <%s>\n",
112 acpi_device_name(device), acpi_device_bid(device)));
114 return_VALUE(0);
117 static int acpi_container_remove(struct acpi_device *device, int type)
119 acpi_status status = AE_OK;
120 struct acpi_container *pc = NULL;
122 pc = (struct acpi_container *)acpi_driver_data(device);
123 kfree(pc);
124 return status;
127 static int container_device_add(struct acpi_device **device, acpi_handle handle)
129 acpi_handle phandle;
130 struct acpi_device *pdev;
131 int result;
133 ACPI_FUNCTION_TRACE("container_device_add");
135 if (acpi_get_parent(handle, &phandle)) {
136 return_VALUE(-ENODEV);
139 if (acpi_bus_get_device(phandle, &pdev)) {
140 return_VALUE(-ENODEV);
143 if (acpi_bus_add(device, pdev, handle, ACPI_BUS_TYPE_DEVICE)) {
144 return_VALUE(-ENODEV);
147 result = acpi_bus_start(*device);
149 return_VALUE(result);
152 static void container_notify_cb(acpi_handle handle, u32 type, void *context)
154 struct acpi_device *device = NULL;
155 int result;
156 int present;
157 acpi_status status;
159 ACPI_FUNCTION_TRACE("container_notify_cb");
161 present = is_device_present(handle);
163 switch (type) {
164 case ACPI_NOTIFY_BUS_CHECK:
165 /* Fall through */
166 case ACPI_NOTIFY_DEVICE_CHECK:
167 printk("Container driver received %s event\n",
168 (type == ACPI_NOTIFY_BUS_CHECK) ?
169 "ACPI_NOTIFY_BUS_CHECK" : "ACPI_NOTIFY_DEVICE_CHECK");
170 status = acpi_bus_get_device(handle, &device);
171 if (present) {
172 if (ACPI_FAILURE(status) || !device) {
173 result = container_device_add(&device, handle);
174 if (!result)
175 kobject_uevent(&device->kobj,
176 KOBJ_ONLINE);
177 else
178 printk("Failed to add container\n");
180 } else {
181 if (ACPI_SUCCESS(status)) {
182 /* device exist and this is a remove request */
183 kobject_uevent(&device->kobj, KOBJ_OFFLINE);
186 break;
187 case ACPI_NOTIFY_EJECT_REQUEST:
188 if (!acpi_bus_get_device(handle, &device) && device) {
189 kobject_uevent(&device->kobj, KOBJ_OFFLINE);
191 break;
192 default:
193 break;
195 return_VOID;
198 static acpi_status
199 container_walk_namespace_cb(acpi_handle handle,
200 u32 lvl, void *context, void **rv)
202 char *hid = NULL;
203 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
204 struct acpi_device_info *info;
205 acpi_status status;
206 int *action = context;
208 ACPI_FUNCTION_TRACE("container_walk_namespace_cb");
210 status = acpi_get_object_info(handle, &buffer);
211 if (ACPI_FAILURE(status) || !buffer.pointer) {
212 return_ACPI_STATUS(AE_OK);
215 info = buffer.pointer;
216 if (info->valid & ACPI_VALID_HID)
217 hid = info->hardware_id.value;
219 if (hid == NULL) {
220 goto end;
223 if (strcmp(hid, "ACPI0004") && strcmp(hid, "PNP0A05") &&
224 strcmp(hid, "PNP0A06")) {
225 goto end;
228 switch (*action) {
229 case INSTALL_NOTIFY_HANDLER:
230 acpi_install_notify_handler(handle,
231 ACPI_SYSTEM_NOTIFY,
232 container_notify_cb, NULL);
233 break;
234 case UNINSTALL_NOTIFY_HANDLER:
235 acpi_remove_notify_handler(handle,
236 ACPI_SYSTEM_NOTIFY,
237 container_notify_cb);
238 break;
239 default:
240 break;
243 end:
244 acpi_os_free(buffer.pointer);
246 return_ACPI_STATUS(AE_OK);
249 static int __init acpi_container_init(void)
251 int result = 0;
252 int action = INSTALL_NOTIFY_HANDLER;
254 result = acpi_bus_register_driver(&acpi_container_driver);
255 if (result < 0) {
256 return (result);
259 /* register notify handler to every container device */
260 acpi_walk_namespace(ACPI_TYPE_DEVICE,
261 ACPI_ROOT_OBJECT,
262 ACPI_UINT32_MAX,
263 container_walk_namespace_cb, &action, NULL);
265 return (0);
268 static void __exit acpi_container_exit(void)
270 int action = UNINSTALL_NOTIFY_HANDLER;
272 ACPI_FUNCTION_TRACE("acpi_container_exit");
274 acpi_walk_namespace(ACPI_TYPE_DEVICE,
275 ACPI_ROOT_OBJECT,
276 ACPI_UINT32_MAX,
277 container_walk_namespace_cb, &action, NULL);
279 acpi_bus_unregister_driver(&acpi_container_driver);
281 return_VOID;
284 module_init(acpi_container_init);
285 module_exit(acpi_container_exit);