acpi: use non-racy method for proc entries creation
[safe/jmp/linux-2.6] / drivers / acpi / ac.c
1 /*
2  *  acpi_ac.c - ACPI AC Adapter Driver ($Revision: 27 $)
3  *
4  *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
5  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
6  *
7  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
8  *
9  *  This program is free software; you can redistribute it and/or modify
10  *  it under the terms of the GNU General Public License as published by
11  *  the Free Software Foundation; either version 2 of the License, or (at
12  *  your option) any later version.
13  *
14  *  This program is distributed in the hope that it will be useful, but
15  *  WITHOUT ANY WARRANTY; without even the implied warranty of
16  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17  *  General Public License for more details.
18  *
19  *  You should have received a copy of the GNU General Public License along
20  *  with this program; if not, write to the Free Software Foundation, Inc.,
21  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
22  *
23  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
24  */
25
26 #include <linux/kernel.h>
27 #include <linux/module.h>
28 #include <linux/init.h>
29 #include <linux/types.h>
30 #ifdef CONFIG_ACPI_PROCFS_POWER
31 #include <linux/proc_fs.h>
32 #include <linux/seq_file.h>
33 #endif
34 #ifdef CONFIG_ACPI_SYSFS_POWER
35 #include <linux/power_supply.h>
36 #endif
37 #include <acpi/acpi_bus.h>
38 #include <acpi/acpi_drivers.h>
39
40 #define ACPI_AC_COMPONENT               0x00020000
41 #define ACPI_AC_CLASS                   "ac_adapter"
42 #define ACPI_AC_DEVICE_NAME             "AC Adapter"
43 #define ACPI_AC_FILE_STATE              "state"
44 #define ACPI_AC_NOTIFY_STATUS           0x80
45 #define ACPI_AC_STATUS_OFFLINE          0x00
46 #define ACPI_AC_STATUS_ONLINE           0x01
47 #define ACPI_AC_STATUS_UNKNOWN          0xFF
48
49 #define _COMPONENT              ACPI_AC_COMPONENT
50 ACPI_MODULE_NAME("ac");
51
52 MODULE_AUTHOR("Paul Diefenbaugh");
53 MODULE_DESCRIPTION("ACPI AC Adapter Driver");
54 MODULE_LICENSE("GPL");
55
56 #ifdef CONFIG_ACPI_PROCFS_POWER
57 extern struct proc_dir_entry *acpi_lock_ac_dir(void);
58 extern void *acpi_unlock_ac_dir(struct proc_dir_entry *acpi_ac_dir);
59 static int acpi_ac_open_fs(struct inode *inode, struct file *file);
60 #endif
61
62 static int acpi_ac_add(struct acpi_device *device);
63 static int acpi_ac_remove(struct acpi_device *device, int type);
64 static int acpi_ac_resume(struct acpi_device *device);
65
66 static const struct acpi_device_id ac_device_ids[] = {
67         {"ACPI0003", 0},
68         {"", 0},
69 };
70 MODULE_DEVICE_TABLE(acpi, ac_device_ids);
71
72 static struct acpi_driver acpi_ac_driver = {
73         .name = "ac",
74         .class = ACPI_AC_CLASS,
75         .ids = ac_device_ids,
76         .ops = {
77                 .add = acpi_ac_add,
78                 .remove = acpi_ac_remove,
79                 .resume = acpi_ac_resume,
80                 },
81 };
82
83 struct acpi_ac {
84 #ifdef CONFIG_ACPI_SYSFS_POWER
85         struct power_supply charger;
86 #endif
87         struct acpi_device * device;
88         unsigned long state;
89 };
90
91 #define to_acpi_ac(x) container_of(x, struct acpi_ac, charger);
92
93 #ifdef CONFIG_ACPI_PROCFS_POWER
94 static const struct file_operations acpi_ac_fops = {
95         .owner = THIS_MODULE,
96         .open = acpi_ac_open_fs,
97         .read = seq_read,
98         .llseek = seq_lseek,
99         .release = single_release,
100 };
101 #endif
102 #ifdef CONFIG_ACPI_SYSFS_POWER
103 static int get_ac_property(struct power_supply *psy,
104                            enum power_supply_property psp,
105                            union power_supply_propval *val)
106 {
107         struct acpi_ac *ac = to_acpi_ac(psy);
108         switch (psp) {
109         case POWER_SUPPLY_PROP_ONLINE:
110                 val->intval = ac->state;
111                 break;
112         default:
113                 return -EINVAL;
114         }
115         return 0;
116 }
117
118 static enum power_supply_property ac_props[] = {
119         POWER_SUPPLY_PROP_ONLINE,
120 };
121 #endif
122 /* --------------------------------------------------------------------------
123                                AC Adapter Management
124    -------------------------------------------------------------------------- */
125
126 static int acpi_ac_get_state(struct acpi_ac *ac)
127 {
128         acpi_status status = AE_OK;
129
130
131         if (!ac)
132                 return -EINVAL;
133
134         status = acpi_evaluate_integer(ac->device->handle, "_PSR", NULL, &ac->state);
135         if (ACPI_FAILURE(status)) {
136                 ACPI_EXCEPTION((AE_INFO, status, "Error reading AC Adapter state"));
137                 ac->state = ACPI_AC_STATUS_UNKNOWN;
138                 return -ENODEV;
139         }
140
141         return 0;
142 }
143
144 #ifdef CONFIG_ACPI_PROCFS_POWER
145 /* --------------------------------------------------------------------------
146                               FS Interface (/proc)
147    -------------------------------------------------------------------------- */
148
149 static struct proc_dir_entry *acpi_ac_dir;
150
151 static int acpi_ac_seq_show(struct seq_file *seq, void *offset)
152 {
153         struct acpi_ac *ac = seq->private;
154
155
156         if (!ac)
157                 return 0;
158
159         if (acpi_ac_get_state(ac)) {
160                 seq_puts(seq, "ERROR: Unable to read AC Adapter state\n");
161                 return 0;
162         }
163
164         seq_puts(seq, "state:                   ");
165         switch (ac->state) {
166         case ACPI_AC_STATUS_OFFLINE:
167                 seq_puts(seq, "off-line\n");
168                 break;
169         case ACPI_AC_STATUS_ONLINE:
170                 seq_puts(seq, "on-line\n");
171                 break;
172         default:
173                 seq_puts(seq, "unknown\n");
174                 break;
175         }
176
177         return 0;
178 }
179
180 static int acpi_ac_open_fs(struct inode *inode, struct file *file)
181 {
182         return single_open(file, acpi_ac_seq_show, PDE(inode)->data);
183 }
184
185 static int acpi_ac_add_fs(struct acpi_device *device)
186 {
187         struct proc_dir_entry *entry = NULL;
188
189
190         if (!acpi_device_dir(device)) {
191                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
192                                                      acpi_ac_dir);
193                 if (!acpi_device_dir(device))
194                         return -ENODEV;
195                 acpi_device_dir(device)->owner = THIS_MODULE;
196         }
197
198         /* 'state' [R] */
199         entry = proc_create_data(ACPI_AC_FILE_STATE,
200                                  S_IRUGO, acpi_device_dir(device),
201                                  &acpi_ac_fops, acpi_driver_data(device));
202         if (!entry)
203                 return -ENODEV;
204         return 0;
205 }
206
207 static int acpi_ac_remove_fs(struct acpi_device *device)
208 {
209
210         if (acpi_device_dir(device)) {
211                 remove_proc_entry(ACPI_AC_FILE_STATE, acpi_device_dir(device));
212
213                 remove_proc_entry(acpi_device_bid(device), acpi_ac_dir);
214                 acpi_device_dir(device) = NULL;
215         }
216
217         return 0;
218 }
219 #endif
220
221 /* --------------------------------------------------------------------------
222                                    Driver Model
223    -------------------------------------------------------------------------- */
224
225 static void acpi_ac_notify(acpi_handle handle, u32 event, void *data)
226 {
227         struct acpi_ac *ac = data;
228         struct acpi_device *device = NULL;
229
230
231         if (!ac)
232                 return;
233
234         device = ac->device;
235         switch (event) {
236         case ACPI_AC_NOTIFY_STATUS:
237         case ACPI_NOTIFY_BUS_CHECK:
238         case ACPI_NOTIFY_DEVICE_CHECK:
239                 acpi_ac_get_state(ac);
240                 acpi_bus_generate_proc_event(device, event, (u32) ac->state);
241                 acpi_bus_generate_netlink_event(device->pnp.device_class,
242                                                   device->dev.bus_id, event,
243                                                   (u32) ac->state);
244 #ifdef CONFIG_ACPI_SYSFS_POWER
245                 kobject_uevent(&ac->charger.dev->kobj, KOBJ_CHANGE);
246 #endif
247                 break;
248         default:
249                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
250                                   "Unsupported event [0x%x]\n", event));
251                 break;
252         }
253
254         return;
255 }
256
257 static int acpi_ac_add(struct acpi_device *device)
258 {
259         int result = 0;
260         acpi_status status = AE_OK;
261         struct acpi_ac *ac = NULL;
262
263
264         if (!device)
265                 return -EINVAL;
266
267         ac = kzalloc(sizeof(struct acpi_ac), GFP_KERNEL);
268         if (!ac)
269                 return -ENOMEM;
270
271         ac->device = device;
272         strcpy(acpi_device_name(device), ACPI_AC_DEVICE_NAME);
273         strcpy(acpi_device_class(device), ACPI_AC_CLASS);
274         acpi_driver_data(device) = ac;
275
276         result = acpi_ac_get_state(ac);
277         if (result)
278                 goto end;
279
280 #ifdef CONFIG_ACPI_PROCFS_POWER
281         result = acpi_ac_add_fs(device);
282 #endif
283         if (result)
284                 goto end;
285 #ifdef CONFIG_ACPI_SYSFS_POWER
286         ac->charger.name = acpi_device_bid(device);
287         ac->charger.type = POWER_SUPPLY_TYPE_MAINS;
288         ac->charger.properties = ac_props;
289         ac->charger.num_properties = ARRAY_SIZE(ac_props);
290         ac->charger.get_property = get_ac_property;
291         power_supply_register(&ac->device->dev, &ac->charger);
292 #endif
293         status = acpi_install_notify_handler(device->handle,
294                                              ACPI_ALL_NOTIFY, acpi_ac_notify,
295                                              ac);
296         if (ACPI_FAILURE(status)) {
297                 result = -ENODEV;
298                 goto end;
299         }
300
301         printk(KERN_INFO PREFIX "%s [%s] (%s)\n",
302                acpi_device_name(device), acpi_device_bid(device),
303                ac->state ? "on-line" : "off-line");
304
305       end:
306         if (result) {
307 #ifdef CONFIG_ACPI_PROCFS_POWER
308                 acpi_ac_remove_fs(device);
309 #endif
310                 kfree(ac);
311         }
312
313         return result;
314 }
315
316 static int acpi_ac_resume(struct acpi_device *device)
317 {
318         struct acpi_ac *ac;
319         unsigned old_state;
320         if (!device || !acpi_driver_data(device))
321                 return -EINVAL;
322         ac = acpi_driver_data(device);
323         old_state = ac->state;
324         if (acpi_ac_get_state(ac))
325                 return 0;
326 #ifdef CONFIG_ACPI_SYSFS_POWER
327         if (old_state != ac->state)
328                 kobject_uevent(&ac->charger.dev->kobj, KOBJ_CHANGE);
329 #endif
330         return 0;
331 }
332
333 static int acpi_ac_remove(struct acpi_device *device, int type)
334 {
335         acpi_status status = AE_OK;
336         struct acpi_ac *ac = NULL;
337
338
339         if (!device || !acpi_driver_data(device))
340                 return -EINVAL;
341
342         ac = acpi_driver_data(device);
343
344         status = acpi_remove_notify_handler(device->handle,
345                                             ACPI_ALL_NOTIFY, acpi_ac_notify);
346 #ifdef CONFIG_ACPI_SYSFS_POWER
347         if (ac->charger.dev)
348                 power_supply_unregister(&ac->charger);
349 #endif
350 #ifdef CONFIG_ACPI_PROCFS_POWER
351         acpi_ac_remove_fs(device);
352 #endif
353
354         kfree(ac);
355
356         return 0;
357 }
358
359 static int __init acpi_ac_init(void)
360 {
361         int result;
362
363         if (acpi_disabled)
364                 return -ENODEV;
365
366 #ifdef CONFIG_ACPI_PROCFS_POWER
367         acpi_ac_dir = acpi_lock_ac_dir();
368         if (!acpi_ac_dir)
369                 return -ENODEV;
370 #endif
371
372         result = acpi_bus_register_driver(&acpi_ac_driver);
373         if (result < 0) {
374 #ifdef CONFIG_ACPI_PROCFS_POWER
375                 acpi_unlock_ac_dir(acpi_ac_dir);
376 #endif
377                 return -ENODEV;
378         }
379
380         return 0;
381 }
382
383 static void __exit acpi_ac_exit(void)
384 {
385
386         acpi_bus_unregister_driver(&acpi_ac_driver);
387
388 #ifdef CONFIG_ACPI_PROCFS_POWER
389         acpi_unlock_ac_dir(acpi_ac_dir);
390 #endif
391
392         return;
393 }
394
395 module_init(acpi_ac_init);
396 module_exit(acpi_ac_exit);