adt7470: make automatic fan control really work
[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_CLASS                  "fan"
38 #define ACPI_FAN_FILE_STATE             "state"
39
40 #define _COMPONENT              ACPI_FAN_COMPONENT
41 ACPI_MODULE_NAME("fan");
42
43 MODULE_AUTHOR("Paul Diefenbaugh");
44 MODULE_DESCRIPTION("ACPI Fan Driver");
45 MODULE_LICENSE("GPL");
46
47 static int acpi_fan_add(struct acpi_device *device);
48 static int acpi_fan_remove(struct acpi_device *device, int type);
49 static int acpi_fan_suspend(struct acpi_device *device, pm_message_t state);
50 static int acpi_fan_resume(struct acpi_device *device);
51
52 static const struct acpi_device_id fan_device_ids[] = {
53         {"PNP0C0B", 0},
54         {"", 0},
55 };
56 MODULE_DEVICE_TABLE(acpi, fan_device_ids);
57
58 static struct acpi_driver acpi_fan_driver = {
59         .name = "fan",
60         .class = ACPI_FAN_CLASS,
61         .ids = fan_device_ids,
62         .ops = {
63                 .add = acpi_fan_add,
64                 .remove = acpi_fan_remove,
65                 .suspend = acpi_fan_suspend,
66                 .resume = acpi_fan_resume,
67                 },
68 };
69
70 /* thermal cooling device callbacks */
71 static int fan_get_max_state(struct thermal_cooling_device *cdev, char *buf)
72 {
73         /* ACPI fan device only support two states: ON/OFF */
74         return sprintf(buf, "1\n");
75 }
76
77 static int fan_get_cur_state(struct thermal_cooling_device *cdev, char *buf)
78 {
79         struct acpi_device *device = cdev->devdata;
80         int state;
81         int result;
82
83         if (!device)
84                 return -EINVAL;
85
86         result = acpi_bus_get_power(device->handle, &state);
87         if (result)
88                 return result;
89
90         return sprintf(buf, "%s\n", state == ACPI_STATE_D3 ? "0" :
91                          (state == ACPI_STATE_D0 ? "1" : "unknown"));
92 }
93
94 static int
95 fan_set_cur_state(struct thermal_cooling_device *cdev, unsigned int state)
96 {
97         struct acpi_device *device = cdev->devdata;
98         int result;
99
100         if (!device || (state != 0 && state != 1))
101                 return -EINVAL;
102
103         result = acpi_bus_set_power(device->handle,
104                                 state ? ACPI_STATE_D0 : ACPI_STATE_D3);
105
106         return result;
107 }
108
109 static struct thermal_cooling_device_ops fan_cooling_ops = {
110         .get_max_state = fan_get_max_state,
111         .get_cur_state = fan_get_cur_state,
112         .set_cur_state = fan_set_cur_state,
113 };
114
115 /* --------------------------------------------------------------------------
116                               FS Interface (/proc)
117    -------------------------------------------------------------------------- */
118 #ifdef CONFIG_ACPI_PROCFS
119
120 static struct proc_dir_entry *acpi_fan_dir;
121
122 static int acpi_fan_read_state(struct seq_file *seq, void *offset)
123 {
124         struct acpi_device *device = seq->private;
125         int state = 0;
126
127
128         if (device) {
129                 if (acpi_bus_get_power(device->handle, &state))
130                         seq_printf(seq, "status:                  ERROR\n");
131                 else
132                         seq_printf(seq, "status:                  %s\n",
133                                    !state ? "on" : "off");
134         }
135         return 0;
136 }
137
138 static int acpi_fan_state_open_fs(struct inode *inode, struct file *file)
139 {
140         return single_open(file, acpi_fan_read_state, PDE(inode)->data);
141 }
142
143 static ssize_t
144 acpi_fan_write_state(struct file *file, const char __user * buffer,
145                      size_t count, loff_t * ppos)
146 {
147         int result = 0;
148         struct seq_file *m = file->private_data;
149         struct acpi_device *device = m->private;
150         char state_string[3] = { '\0' };
151
152         if (count > sizeof(state_string) - 1)
153                 return -EINVAL;
154
155         if (copy_from_user(state_string, buffer, count))
156                 return -EFAULT;
157
158         state_string[count] = '\0';
159         if ((state_string[0] < '0') || (state_string[0] > '3'))
160                 return -EINVAL;
161         if (state_string[1] == '\n')
162                 state_string[1] = '\0';
163         if (state_string[1] != '\0')
164                 return -EINVAL;
165
166         result = acpi_bus_set_power(device->handle,
167                                     simple_strtoul(state_string, NULL, 0));
168         if (result)
169                 return result;
170
171         return count;
172 }
173
174 static const struct file_operations acpi_fan_state_ops = {
175         .open = acpi_fan_state_open_fs,
176         .read = seq_read,
177         .write = acpi_fan_write_state,
178         .llseek = seq_lseek,
179         .release = single_release,
180         .owner = THIS_MODULE,
181 };
182
183 static int acpi_fan_add_fs(struct acpi_device *device)
184 {
185         struct proc_dir_entry *entry = NULL;
186
187
188         if (!device)
189                 return -EINVAL;
190
191         if (!acpi_device_dir(device)) {
192                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
193                                                      acpi_fan_dir);
194                 if (!acpi_device_dir(device))
195                         return -ENODEV;
196                 acpi_device_dir(device)->owner = THIS_MODULE;
197         }
198
199         /* 'status' [R/W] */
200         entry = proc_create_data(ACPI_FAN_FILE_STATE,
201                                  S_IFREG | S_IRUGO | S_IWUSR,
202                                  acpi_device_dir(device),
203                                  &acpi_fan_state_ops,
204                                  device);
205         if (!entry)
206                 return -ENODEV;
207         return 0;
208 }
209
210 static int acpi_fan_remove_fs(struct acpi_device *device)
211 {
212
213         if (acpi_device_dir(device)) {
214                 remove_proc_entry(ACPI_FAN_FILE_STATE, acpi_device_dir(device));
215                 remove_proc_entry(acpi_device_bid(device), acpi_fan_dir);
216                 acpi_device_dir(device) = NULL;
217         }
218
219         return 0;
220 }
221 #else
222 static int acpi_fan_add_fs(struct acpi_device *device)
223 {
224         return 0;
225 }
226
227 static int acpi_fan_remove_fs(struct acpi_device *device)
228 {
229         return 0;
230 }
231 #endif
232 /* --------------------------------------------------------------------------
233                                  Driver Interface
234    -------------------------------------------------------------------------- */
235
236 static int acpi_fan_add(struct acpi_device *device)
237 {
238         int result = 0;
239         int state = 0;
240         struct thermal_cooling_device *cdev;
241
242         if (!device)
243                 return -EINVAL;
244
245         strcpy(acpi_device_name(device), "Fan");
246         strcpy(acpi_device_class(device), ACPI_FAN_CLASS);
247
248         result = acpi_bus_get_power(device->handle, &state);
249         if (result) {
250                 printk(KERN_ERR PREFIX "Reading power state\n");
251                 goto end;
252         }
253
254         device->flags.force_power_state = 1;
255         acpi_bus_set_power(device->handle, state);
256         device->flags.force_power_state = 0;
257
258         cdev = thermal_cooling_device_register("Fan", device,
259                                                 &fan_cooling_ops);
260         if (IS_ERR(cdev)) {
261                 result = PTR_ERR(cdev);
262                 goto end;
263         }
264
265         dev_info(&device->dev, "registered as cooling_device%d\n", cdev->id);
266
267         device->driver_data = cdev;
268         result = sysfs_create_link(&device->dev.kobj,
269                                    &cdev->device.kobj,
270                                    "thermal_cooling");
271         if (result)
272                 dev_err(&device->dev, "Failed to create sysfs link "
273                         "'thermal_cooling'\n");
274
275         result = sysfs_create_link(&cdev->device.kobj,
276                                    &device->dev.kobj,
277                                    "device");
278         if (result)
279                 dev_err(&device->dev, "Failed to create sysfs link "
280                         "'device'\n");
281
282         result = acpi_fan_add_fs(device);
283         if (result)
284                 goto end;
285
286         printk(KERN_INFO PREFIX "%s [%s] (%s)\n",
287                acpi_device_name(device), acpi_device_bid(device),
288                !device->power.state ? "on" : "off");
289
290       end:
291         return result;
292 }
293
294 static int acpi_fan_remove(struct acpi_device *device, int type)
295 {
296         struct thermal_cooling_device *cdev = acpi_driver_data(device);
297
298         if (!device || !cdev)
299                 return -EINVAL;
300
301         acpi_fan_remove_fs(device);
302         sysfs_remove_link(&device->dev.kobj, "thermal_cooling");
303         sysfs_remove_link(&cdev->device.kobj, "device");
304         thermal_cooling_device_unregister(cdev);
305
306         return 0;
307 }
308
309 static int acpi_fan_suspend(struct acpi_device *device, pm_message_t state)
310 {
311         if (!device)
312                 return -EINVAL;
313
314         acpi_bus_set_power(device->handle, ACPI_STATE_D0);
315
316         return AE_OK;
317 }
318
319 static int acpi_fan_resume(struct acpi_device *device)
320 {
321         int result = 0;
322         int power_state = 0;
323
324         if (!device)
325                 return -EINVAL;
326
327         result = acpi_bus_get_power(device->handle, &power_state);
328         if (result) {
329                 printk(KERN_ERR PREFIX
330                                   "Error reading fan power state\n");
331                 return result;
332         }
333
334         device->flags.force_power_state = 1;
335         acpi_bus_set_power(device->handle, power_state);
336         device->flags.force_power_state = 0;
337
338         return result;
339 }
340
341 static int __init acpi_fan_init(void)
342 {
343         int result = 0;
344
345
346 #ifdef CONFIG_ACPI_PROCFS
347         acpi_fan_dir = proc_mkdir(ACPI_FAN_CLASS, acpi_root_dir);
348         if (!acpi_fan_dir)
349                 return -ENODEV;
350         acpi_fan_dir->owner = THIS_MODULE;
351 #endif
352
353         result = acpi_bus_register_driver(&acpi_fan_driver);
354         if (result < 0) {
355                 remove_proc_entry(ACPI_FAN_CLASS, acpi_root_dir);
356                 return -ENODEV;
357         }
358
359         return 0;
360 }
361
362 static void __exit acpi_fan_exit(void)
363 {
364
365         acpi_bus_unregister_driver(&acpi_fan_driver);
366
367         remove_proc_entry(ACPI_FAN_CLASS, acpi_root_dir);
368
369         return;
370 }
371
372 module_init(acpi_fan_init);
373 module_exit(acpi_fan_exit);