Documentation cleanup: trivial misspelling, punctuation, and grammar corrections.
[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 #include <linux/thermal.h>
34 #include <acpi/acpi_bus.h>
35 #include <acpi/acpi_drivers.h>
36
37 #define ACPI_FAN_COMPONENT              0x00200000
38 #define ACPI_FAN_CLASS                  "fan"
39 #define ACPI_FAN_FILE_STATE             "state"
40
41 #define _COMPONENT              ACPI_FAN_COMPONENT
42 ACPI_MODULE_NAME("fan");
43
44 MODULE_AUTHOR("Paul Diefenbaugh");
45 MODULE_DESCRIPTION("ACPI Fan Driver");
46 MODULE_LICENSE("GPL");
47
48 static int acpi_fan_add(struct acpi_device *device);
49 static int acpi_fan_remove(struct acpi_device *device, int type);
50 static int acpi_fan_suspend(struct acpi_device *device, pm_message_t state);
51 static int acpi_fan_resume(struct acpi_device *device);
52
53 static const struct acpi_device_id fan_device_ids[] = {
54         {"PNP0C0B", 0},
55         {"", 0},
56 };
57 MODULE_DEVICE_TABLE(acpi, fan_device_ids);
58
59 static struct acpi_driver acpi_fan_driver = {
60         .name = "fan",
61         .class = ACPI_FAN_CLASS,
62         .ids = fan_device_ids,
63         .ops = {
64                 .add = acpi_fan_add,
65                 .remove = acpi_fan_remove,
66                 .suspend = acpi_fan_suspend,
67                 .resume = acpi_fan_resume,
68                 },
69 };
70
71 /* thermal cooling device callbacks */
72 static int fan_get_max_state(struct thermal_cooling_device *cdev, char *buf)
73 {
74         /* ACPI fan device only support two states: ON/OFF */
75         return sprintf(buf, "1\n");
76 }
77
78 static int fan_get_cur_state(struct thermal_cooling_device *cdev, char *buf)
79 {
80         struct acpi_device *device = cdev->devdata;
81         int state;
82         int result;
83
84         if (!device)
85                 return -EINVAL;
86
87         result = acpi_bus_get_power(device->handle, &state);
88         if (result)
89                 return result;
90
91         return sprintf(buf, "%s\n", state == ACPI_STATE_D3 ? "0" :
92                          (state == ACPI_STATE_D0 ? "1" : "unknown"));
93 }
94
95 static int
96 fan_set_cur_state(struct thermal_cooling_device *cdev, unsigned int state)
97 {
98         struct acpi_device *device = cdev->devdata;
99         int result;
100
101         if (!device || (state != 0 && state != 1))
102                 return -EINVAL;
103
104         result = acpi_bus_set_power(device->handle,
105                                 state ? ACPI_STATE_D0 : ACPI_STATE_D3);
106
107         return result;
108 }
109
110 static struct thermal_cooling_device_ops fan_cooling_ops = {
111         .get_max_state = fan_get_max_state,
112         .get_cur_state = fan_get_cur_state,
113         .set_cur_state = fan_set_cur_state,
114 };
115
116 /* --------------------------------------------------------------------------
117                               FS Interface (/proc)
118    -------------------------------------------------------------------------- */
119 #ifdef CONFIG_ACPI_PROCFS
120
121 static struct proc_dir_entry *acpi_fan_dir;
122
123 static int acpi_fan_read_state(struct seq_file *seq, void *offset)
124 {
125         struct acpi_device *device = seq->private;
126         int state = 0;
127
128
129         if (device) {
130                 if (acpi_bus_get_power(device->handle, &state))
131                         seq_printf(seq, "status:                  ERROR\n");
132                 else
133                         seq_printf(seq, "status:                  %s\n",
134                                    !state ? "on" : "off");
135         }
136         return 0;
137 }
138
139 static int acpi_fan_state_open_fs(struct inode *inode, struct file *file)
140 {
141         return single_open(file, acpi_fan_read_state, PDE(inode)->data);
142 }
143
144 static ssize_t
145 acpi_fan_write_state(struct file *file, const char __user * buffer,
146                      size_t count, loff_t * ppos)
147 {
148         int result = 0;
149         struct seq_file *m = file->private_data;
150         struct acpi_device *device = m->private;
151         char state_string[3] = { '\0' };
152
153         if (count > sizeof(state_string) - 1)
154                 return -EINVAL;
155
156         if (copy_from_user(state_string, buffer, count))
157                 return -EFAULT;
158
159         state_string[count] = '\0';
160         if ((state_string[0] < '0') || (state_string[0] > '3'))
161                 return -EINVAL;
162         if (state_string[1] == '\n')
163                 state_string[1] = '\0';
164         if (state_string[1] != '\0')
165                 return -EINVAL;
166
167         result = acpi_bus_set_power(device->handle,
168                                     simple_strtoul(state_string, NULL, 0));
169         if (result)
170                 return result;
171
172         return count;
173 }
174
175 static const struct file_operations acpi_fan_state_ops = {
176         .open = acpi_fan_state_open_fs,
177         .read = seq_read,
178         .write = acpi_fan_write_state,
179         .llseek = seq_lseek,
180         .release = single_release,
181         .owner = THIS_MODULE,
182 };
183
184 static int acpi_fan_add_fs(struct acpi_device *device)
185 {
186         struct proc_dir_entry *entry = NULL;
187
188
189         if (!device)
190                 return -EINVAL;
191
192         if (!acpi_device_dir(device)) {
193                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
194                                                      acpi_fan_dir);
195                 if (!acpi_device_dir(device))
196                         return -ENODEV;
197                 acpi_device_dir(device)->owner = THIS_MODULE;
198         }
199
200         /* 'status' [R/W] */
201         entry = proc_create_data(ACPI_FAN_FILE_STATE,
202                                  S_IFREG | S_IRUGO | S_IWUSR,
203                                  acpi_device_dir(device),
204                                  &acpi_fan_state_ops,
205                                  device);
206         if (!entry)
207                 return -ENODEV;
208         return 0;
209 }
210
211 static int acpi_fan_remove_fs(struct acpi_device *device)
212 {
213
214         if (acpi_device_dir(device)) {
215                 remove_proc_entry(ACPI_FAN_FILE_STATE, acpi_device_dir(device));
216                 remove_proc_entry(acpi_device_bid(device), acpi_fan_dir);
217                 acpi_device_dir(device) = NULL;
218         }
219
220         return 0;
221 }
222 #else
223 static int acpi_fan_add_fs(struct acpi_device *device)
224 {
225         return 0;
226 }
227
228 static int acpi_fan_remove_fs(struct acpi_device *device)
229 {
230         return 0;
231 }
232 #endif
233 /* --------------------------------------------------------------------------
234                                  Driver Interface
235    -------------------------------------------------------------------------- */
236
237 static int acpi_fan_add(struct acpi_device *device)
238 {
239         int result = 0;
240         int state = 0;
241         struct thermal_cooling_device *cdev;
242
243         if (!device)
244                 return -EINVAL;
245
246         strcpy(acpi_device_name(device), "Fan");
247         strcpy(acpi_device_class(device), ACPI_FAN_CLASS);
248
249         result = acpi_bus_get_power(device->handle, &state);
250         if (result) {
251                 printk(KERN_ERR PREFIX "Reading power state\n");
252                 goto end;
253         }
254
255         device->flags.force_power_state = 1;
256         acpi_bus_set_power(device->handle, state);
257         device->flags.force_power_state = 0;
258
259         cdev = thermal_cooling_device_register("Fan", device,
260                                                 &fan_cooling_ops);
261         if (IS_ERR(cdev)) {
262                 result = PTR_ERR(cdev);
263                 goto end;
264         }
265
266         dev_info(&device->dev, "registered as cooling_device%d\n", cdev->id);
267
268         acpi_driver_data(device) = cdev;
269         result = sysfs_create_link(&device->dev.kobj,
270                                    &cdev->device.kobj,
271                                    "thermal_cooling");
272         if (result)
273                 dev_err(&device->dev, "Failed to create sysfs link "
274                         "'thermal_cooling'\n");
275
276         result = sysfs_create_link(&cdev->device.kobj,
277                                    &device->dev.kobj,
278                                    "device");
279         if (result)
280                 dev_err(&device->dev, "Failed to create sysfs link "
281                         "'device'\n");
282
283         result = acpi_fan_add_fs(device);
284         if (result)
285                 goto end;
286
287         printk(KERN_INFO PREFIX "%s [%s] (%s)\n",
288                acpi_device_name(device), acpi_device_bid(device),
289                !device->power.state ? "on" : "off");
290
291       end:
292         return result;
293 }
294
295 static int acpi_fan_remove(struct acpi_device *device, int type)
296 {
297         struct thermal_cooling_device *cdev = acpi_driver_data(device);
298
299         if (!device || !cdev)
300                 return -EINVAL;
301
302         acpi_fan_remove_fs(device);
303         sysfs_remove_link(&device->dev.kobj, "thermal_cooling");
304         sysfs_remove_link(&cdev->device.kobj, "device");
305         thermal_cooling_device_unregister(cdev);
306
307         return 0;
308 }
309
310 static int acpi_fan_suspend(struct acpi_device *device, pm_message_t state)
311 {
312         if (!device)
313                 return -EINVAL;
314
315         acpi_bus_set_power(device->handle, ACPI_STATE_D0);
316
317         return AE_OK;
318 }
319
320 static int acpi_fan_resume(struct acpi_device *device)
321 {
322         int result = 0;
323         int power_state = 0;
324
325         if (!device)
326                 return -EINVAL;
327
328         result = acpi_bus_get_power(device->handle, &power_state);
329         if (result) {
330                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
331                                   "Error reading fan power state\n"));
332                 return result;
333         }
334
335         device->flags.force_power_state = 1;
336         acpi_bus_set_power(device->handle, power_state);
337         device->flags.force_power_state = 0;
338
339         return result;
340 }
341
342 static int __init acpi_fan_init(void)
343 {
344         int result = 0;
345
346
347 #ifdef CONFIG_ACPI_PROCFS
348         acpi_fan_dir = proc_mkdir(ACPI_FAN_CLASS, acpi_root_dir);
349         if (!acpi_fan_dir)
350                 return -ENODEV;
351         acpi_fan_dir->owner = THIS_MODULE;
352 #endif
353
354         result = acpi_bus_register_driver(&acpi_fan_driver);
355         if (result < 0) {
356                 remove_proc_entry(ACPI_FAN_CLASS, acpi_root_dir);
357                 return -ENODEV;
358         }
359
360         return 0;
361 }
362
363 static void __exit acpi_fan_exit(void)
364 {
365
366         acpi_bus_unregister_driver(&acpi_fan_driver);
367
368         remove_proc_entry(ACPI_FAN_CLASS, acpi_root_dir);
369
370         return;
371 }
372
373 module_init(acpi_fan_init);
374 module_exit(acpi_fan_exit);