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 */
fan_get_max_state(struct thermal_cooling_device * cdev,char * buf)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
fan_get_cur_state(struct thermal_cooling_device * cdev,char * buf)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
fan_set_cur_state(struct thermal_cooling_device * cdev,unsigned int state)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
acpi_fan_read_state(struct seq_file * seq,void * offset)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
acpi_fan_state_open_fs(struct inode * inode,struct file * file)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
acpi_fan_write_state(struct file * file,const char __user * buffer,size_t count,loff_t * ppos)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
acpi_fan_add_fs(struct acpi_device * device)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
acpi_fan_remove_fs(struct acpi_device * device)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
acpi_fan_add_fs(struct acpi_device * device)222 static int acpi_fan_add_fs(struct acpi_device *device)
223 {
224 return 0;
225 }
226
acpi_fan_remove_fs(struct acpi_device * device)227 static int acpi_fan_remove_fs(struct acpi_device *device)
228 {
229 return 0;
230 }
231 #endif
232 /* --------------------------------------------------------------------------
233 Driver Interface
234 -------------------------------------------------------------------------- */
235
acpi_fan_add(struct acpi_device * device)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
acpi_fan_remove(struct acpi_device * device,int type)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
acpi_fan_suspend(struct acpi_device * device,pm_message_t state)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
acpi_fan_resume(struct acpi_device * device)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
acpi_fan_init(void)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
acpi_fan_exit(void)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);
374