[PATCH] Fix ide-disk.c oops caused by hwif == NULL
[linux-2.6] / drivers / acpi / fan.c
1 /*
2  *  acpi_fan.c - ACPI Fan Driver ($Revision: 29 $)
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 #include <linux/proc_fs.h>
31 #include <linux/seq_file.h>
32 #include <asm/uaccess.h>
33
34 #include <acpi/acpi_bus.h>
35 #include <acpi/acpi_drivers.h>
36
37
38 #define ACPI_FAN_COMPONENT              0x00200000
39 #define ACPI_FAN_CLASS                  "fan"
40 #define ACPI_FAN_HID                    "PNP0C0B"
41 #define ACPI_FAN_DRIVER_NAME            "ACPI Fan Driver"
42 #define ACPI_FAN_DEVICE_NAME            "Fan"
43 #define ACPI_FAN_FILE_STATE             "state"
44 #define ACPI_FAN_NOTIFY_STATUS          0x80
45
46 #define _COMPONENT              ACPI_FAN_COMPONENT
47 ACPI_MODULE_NAME                ("acpi_fan")
48
49 MODULE_AUTHOR("Paul Diefenbaugh");
50 MODULE_DESCRIPTION(ACPI_FAN_DRIVER_NAME);
51 MODULE_LICENSE("GPL");
52
53 static int acpi_fan_add (struct acpi_device *device);
54 static int acpi_fan_remove (struct acpi_device *device, int type);
55
56 static struct acpi_driver acpi_fan_driver = {
57         .name =         ACPI_FAN_DRIVER_NAME,
58         .class =        ACPI_FAN_CLASS,
59         .ids =          ACPI_FAN_HID,
60         .ops =          {
61                                 .add =          acpi_fan_add,
62                                 .remove =       acpi_fan_remove,
63                         },
64 };
65
66 struct acpi_fan {
67         acpi_handle             handle;
68 };
69
70
71 /* --------------------------------------------------------------------------
72                               FS Interface (/proc)
73    -------------------------------------------------------------------------- */
74
75 static struct proc_dir_entry    *acpi_fan_dir;
76
77
78 static int
79 acpi_fan_read_state (struct seq_file *seq, void *offset)
80 {
81         struct acpi_fan         *fan = seq->private;
82         int                     state = 0;
83
84         ACPI_FUNCTION_TRACE("acpi_fan_read_state");
85
86         if (fan) {
87                 if (acpi_bus_get_power(fan->handle, &state))
88                         seq_printf(seq, "status:                  ERROR\n");
89                 else
90                         seq_printf(seq, "status:                  %s\n",
91                                      !state?"on":"off");
92         }
93         return_VALUE(0);
94 }
95
96 static int acpi_fan_state_open_fs(struct inode *inode, struct file *file)
97 {
98         return single_open(file, acpi_fan_read_state, PDE(inode)->data);
99 }
100
101 static ssize_t
102 acpi_fan_write_state (
103         struct file             *file,
104         const char              __user *buffer,
105         size_t                  count,
106         loff_t                  *ppos)
107 {
108         int                     result = 0;
109         struct seq_file         *m = (struct seq_file *)file->private_data;
110         struct acpi_fan         *fan = (struct acpi_fan *) m->private;
111         char                    state_string[12] = {'\0'};
112
113         ACPI_FUNCTION_TRACE("acpi_fan_write_state");
114
115         if (!fan || (count > sizeof(state_string) - 1))
116                 return_VALUE(-EINVAL);
117         
118         if (copy_from_user(state_string, buffer, count))
119                 return_VALUE(-EFAULT);
120         
121         state_string[count] = '\0';
122         
123         result = acpi_bus_set_power(fan->handle, 
124                 simple_strtoul(state_string, NULL, 0));
125         if (result)
126                 return_VALUE(result);
127
128         return_VALUE(count);
129 }
130
131 static struct file_operations acpi_fan_state_ops = {
132         .open           = acpi_fan_state_open_fs,
133         .read           = seq_read,
134         .write          = acpi_fan_write_state,
135         .llseek         = seq_lseek,
136         .release        = single_release,
137         .owner = THIS_MODULE,
138 };
139
140 static int
141 acpi_fan_add_fs (
142         struct acpi_device      *device)
143 {
144         struct proc_dir_entry   *entry = NULL;
145
146         ACPI_FUNCTION_TRACE("acpi_fan_add_fs");
147
148         if (!device)
149                 return_VALUE(-EINVAL);
150
151         if (!acpi_device_dir(device)) {
152                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
153                         acpi_fan_dir);
154                 if (!acpi_device_dir(device))
155                         return_VALUE(-ENODEV);
156                 acpi_device_dir(device)->owner = THIS_MODULE;
157         }
158
159         /* 'status' [R/W] */
160         entry = create_proc_entry(ACPI_FAN_FILE_STATE,
161                 S_IFREG|S_IRUGO|S_IWUSR, acpi_device_dir(device));
162         if (!entry)
163                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
164                         "Unable to create '%s' fs entry\n",
165                         ACPI_FAN_FILE_STATE));
166         else {
167                 entry->proc_fops = &acpi_fan_state_ops;
168                 entry->data = acpi_driver_data(device);
169                 entry->owner = THIS_MODULE;
170         }
171
172         return_VALUE(0);
173 }
174
175
176 static int
177 acpi_fan_remove_fs (
178         struct acpi_device      *device)
179 {
180         ACPI_FUNCTION_TRACE("acpi_fan_remove_fs");
181
182         if (acpi_device_dir(device)) {
183                 remove_proc_entry(ACPI_FAN_FILE_STATE,
184                                   acpi_device_dir(device));
185                 remove_proc_entry(acpi_device_bid(device), acpi_fan_dir);
186                 acpi_device_dir(device) = NULL;
187         }
188
189         return_VALUE(0);
190 }
191
192
193 /* --------------------------------------------------------------------------
194                                  Driver Interface
195    -------------------------------------------------------------------------- */
196
197 static int
198 acpi_fan_add (
199         struct acpi_device      *device)
200 {
201         int                     result = 0;
202         struct acpi_fan         *fan = NULL;
203         int                     state = 0;
204
205         ACPI_FUNCTION_TRACE("acpi_fan_add");
206
207         if (!device)
208                 return_VALUE(-EINVAL);
209
210         fan = kmalloc(sizeof(struct acpi_fan), GFP_KERNEL);
211         if (!fan)
212                 return_VALUE(-ENOMEM);
213         memset(fan, 0, sizeof(struct acpi_fan));
214
215         fan->handle = device->handle;
216         strcpy(acpi_device_name(device), ACPI_FAN_DEVICE_NAME);
217         strcpy(acpi_device_class(device), ACPI_FAN_CLASS);
218         acpi_driver_data(device) = fan;
219
220         result = acpi_bus_get_power(fan->handle, &state);
221         if (result) {
222                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
223                         "Error reading power state\n"));
224                 goto end;
225         }
226
227         result = acpi_fan_add_fs(device);
228         if (result)
229                 goto end;
230
231         printk(KERN_INFO PREFIX "%s [%s] (%s)\n",
232                 acpi_device_name(device), acpi_device_bid(device),
233                 !device->power.state?"on":"off");
234
235 end:
236         if (result)
237                 kfree(fan);
238
239         return_VALUE(result);
240 }
241
242
243 static int
244 acpi_fan_remove (
245         struct acpi_device      *device,
246         int                     type)
247 {
248         struct acpi_fan         *fan = NULL;
249
250         ACPI_FUNCTION_TRACE("acpi_fan_remove");
251
252         if (!device || !acpi_driver_data(device))
253                 return_VALUE(-EINVAL);
254
255         fan = (struct acpi_fan *) acpi_driver_data(device);
256
257         acpi_fan_remove_fs(device);
258
259         kfree(fan);
260
261         return_VALUE(0);
262 }
263
264
265 static int __init
266 acpi_fan_init (void)
267 {
268         int                     result = 0;
269
270         ACPI_FUNCTION_TRACE("acpi_fan_init");
271
272         acpi_fan_dir = proc_mkdir(ACPI_FAN_CLASS, acpi_root_dir);
273         if (!acpi_fan_dir)
274                 return_VALUE(-ENODEV);
275         acpi_fan_dir->owner = THIS_MODULE;
276
277         result = acpi_bus_register_driver(&acpi_fan_driver);
278         if (result < 0) {
279                 remove_proc_entry(ACPI_FAN_CLASS, acpi_root_dir);
280                 return_VALUE(-ENODEV);
281         }
282
283         return_VALUE(0);
284 }
285
286
287 static void __exit
288 acpi_fan_exit (void)
289 {
290         ACPI_FUNCTION_TRACE("acpi_fan_exit");
291
292         acpi_bus_unregister_driver(&acpi_fan_driver);
293
294         remove_proc_entry(ACPI_FAN_CLASS, acpi_root_dir);
295
296         return_VOID;
297 }
298
299
300 module_init(acpi_fan_init);
301 module_exit(acpi_fan_exit);
302