aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/acpi/fan.c
blob: 8a02944bf92d687e4b1cf5c3e79b8efce59c9d6a (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
/*
 *  acpi_fan.c - ACPI Fan Driver ($Revision: 29 $)
 *
 *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
 *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
 *
 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or (at
 *  your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful, but
 *  WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 *  General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License along
 *  with this program; if not, write to the Free Software Foundation, Inc.,
 *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
 *
 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <asm/uaccess.h>
#include <linux/thermal.h>
#include <acpi/acpi_bus.h>
#include <acpi/acpi_drivers.h>

#define ACPI_FAN_CLASS			"fan"
#define ACPI_FAN_FILE_STATE		"state"

#define _COMPONENT		ACPI_FAN_COMPONENT
ACPI_MODULE_NAME("fan");

MODULE_AUTHOR("Paul Diefenbaugh");
MODULE_DESCRIPTION("ACPI Fan Driver");
MODULE_LICENSE("GPL");

static int acpi_fan_add(struct acpi_device *device);
static int acpi_fan_remove(struct acpi_device *device, int type);
static int acpi_fan_suspend(struct acpi_device *device, pm_message_t state);
static int acpi_fan_resume(struct acpi_device *device);

static const struct acpi_device_id fan_device_ids[] = {
	{"PNP0C0B", 0},
	{"", 0},
};
MODULE_DEVICE_TABLE(acpi, fan_device_ids);

static struct acpi_driver acpi_fan_driver = {
	.name = "fan",
	.class = ACPI_FAN_CLASS,
	.ids = fan_device_ids,
	.ops = {
		.add = acpi_fan_add,
		.remove = acpi_fan_remove,
		.suspend = acpi_fan_suspend,
		.resume = acpi_fan_resume,
		},
};

/* thermal cooling device callbacks */
static int fan_get_max_state(struct thermal_cooling_device *cdev, char *buf)
{
	/* ACPI fan device only support two states: ON/OFF */
	return sprintf(buf, "1\n");
}

static int fan_get_cur_state(struct thermal_cooling_device *cdev, char *buf)
{
	struct acpi_device *device = cdev->devdata;
	int state;
	int result;

	if (!device)
		return -EINVAL;

	result = acpi_bus_get_power(device->handle, &state);
	if (result)
		return result;

	return sprintf(buf, "%s\n", state == ACPI_STATE_D3 ? "0" :
			 (state == ACPI_STATE_D0 ? "1" : "unknown"));
}

static int
fan_set_cur_state(struct thermal_cooling_device *cdev, unsigned int state)
{
	struct acpi_device *device = cdev->devdata;
	int result;

	if (!device || (state != 0 && state != 1))
		return -EINVAL;

	result = acpi_bus_set_power(device->handle,
				state ? ACPI_STATE_D0 : ACPI_STATE_D3);

	return result;
}

static struct thermal_cooling_device_ops fan_cooling_ops = {
	.get_max_state = fan_get_max_state,
	.get_cur_state = fan_get_cur_state,
	.set_cur_state = fan_set_cur_state,
};

/* --------------------------------------------------------------------------
                              FS Interface (/proc)
   -------------------------------------------------------------------------- */
#ifdef CONFIG_ACPI_PROCFS

static struct proc_dir_entry *acpi_fan_dir;

static int acpi_fan_read_state(struct seq_file *seq, void *offset)
{
	struct acpi_device *device = seq->private;
	int state = 0;


	if (device) {
		if (acpi_bus_get_power(device->handle, &state))
			seq_printf(seq, "status:                  ERROR\n");
		else
			seq_printf(seq, "status:                  %s\n",
				   !state ? "on" : "off");
	}
	return 0;
}

static int acpi_fan_state_open_fs(struct inode *inode, struct file *file)
{
	return single_open(file, acpi_fan_read_state, PDE(inode)->data);
}

static ssize_t
acpi_fan_write_state(struct file *file, const char __user * buffer,
		     size_t count, loff_t * ppos)
{
	int result = 0;
	struct seq_file *m = file->private_data;
	struct acpi_device *device = m->private;
	char state_string[3] = { '\0' };

	if (count > sizeof(state_string) - 1)
		return -EINVAL;

	if (copy_from_user(state_string, buffer, count))
		return -EFAULT;

	state_string[count] = '\0';
	if ((state_string[0] < '0') || (state_string[0] > '3'))
		return -EINVAL;
	if (state_string[1] == '\n')
		state_string[1] = '\0';
	if (state_string[1] != '\0')
		return -EINVAL;

	result = acpi_bus_set_power(device->handle,
				    simple_strtoul(state_string, NULL, 0));
	if (result)
		return result;

	return count;
}

static const struct file_operations acpi_fan_state_ops = {
	.open = acpi_fan_state_open_fs,
	.read = seq_read,
	.write = acpi_fan_write_state,
	.llseek = seq_lseek,
	.release = single_release,
	.owner = THIS_MODULE,
};

static int acpi_fan_add_fs(struct acpi_device *device)
{
	struct proc_dir_entry *entry = NULL;


	if (!device)
		return -EINVAL;

	if (!acpi_device_dir(device)) {
		acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
						     acpi_fan_dir);
		if (!acpi_device_dir(device))
			return -ENODEV;
	}

	/* 'status' [R/W] */
	entry = proc_create_data(ACPI_FAN_FILE_STATE,
				 S_IFREG | S_IRUGO | S_IWUSR,
				 acpi_device_dir(device),
				 &acpi_fan_state_ops,
				 device);
	if (!entry)
		return -ENODEV;
	return 0;
}

static int acpi_fan_remove_fs(struct acpi_device *device)
{

	if (acpi_device_dir(device)) {
		remove_proc_entry(ACPI_FAN_FILE_STATE, acpi_device_dir(device));
		remove_proc_entry(acpi_device_bid(device), acpi_fan_dir);
		acpi_device_dir(device) = NULL;
	}

	return 0;
}
#else
static int acpi_fan_add_fs(struct acpi_device *device)
{
	return 0;
}

static int acpi_fan_remove_fs(struct acpi_device *device)
{
	return 0;
}
#endif
/* --------------------------------------------------------------------------
                                 Driver Interface
   -------------------------------------------------------------------------- */

static int acpi_fan_add(struct acpi_device *device)
{
	int result = 0;
	int state = 0;
	struct thermal_cooling_device *cdev;

	if (!device)
		return -EINVAL;

	strcpy(acpi_device_name(device), "Fan");
	strcpy(acpi_device_class(device), ACPI_FAN_CLASS);

	result = acpi_bus_get_power(device->handle, &state);
	if (result) {
		printk(KERN_ERR PREFIX "Reading power state\n");
		goto end;
	}

	device->flags.force_power_state = 1;
	acpi_bus_set_power(device->handle, state);
	device->flags.force_power_state = 0;

	cdev = thermal_cooling_device_register("Fan", device,
						&fan_cooling_ops);
	if (IS_ERR(cdev)) {
		result = PTR_ERR(cdev);
		goto end;
	}

	dev_info(&device->dev, "registered as cooling_device%d\n", cdev->id);

	device->driver_data = cdev;
	result = sysfs_create_link(&device->dev.kobj,
				   &cdev->device.kobj,
				   "thermal_cooling");
	if (result)
		dev_err(&device->dev, "Failed to create sysfs link "
			"'thermal_cooling'\n");

	result = sysfs_create_link(&cdev->device.kobj,
				   &device->dev.kobj,
				   "device");
	if (result)
		dev_err(&device->dev, "Failed to create sysfs link "
			"'device'\n");

	result = acpi_fan_add_fs(device);
	if (result)
		goto end;

	printk(KERN_INFO PREFIX "%s [%s] (%s)\n",
	       acpi_device_name(device), acpi_device_bid(device),
	       !device->power.state ? "on" : "off");

      end:
	return result;
}

static int acpi_fan_remove(struct acpi_device *device, int type)
{
	struct thermal_cooling_device *cdev = acpi_driver_data(device);

	if (!device || !cdev)
		return -EINVAL;

	acpi_fan_remove_fs(device);
	sysfs_remove_link(&device->dev.kobj, "thermal_cooling");
	sysfs_remove_link(&cdev->device.kobj, "device");
	thermal_cooling_device_unregister(cdev);

	return 0;
}

static int acpi_fan_suspend(struct acpi_device *device, pm_message_t state)
{
	if (!device)
		return -EINVAL;

	acpi_bus_set_power(device->handle, ACPI_STATE_D0);

	return AE_OK;
}

static int acpi_fan_resume(struct acpi_device *device)
{
	int result = 0;
	int power_state = 0;

	if (!device)
		return -EINVAL;

	result = acpi_bus_get_power(device->handle, &power_state);
	if (result) {
		printk(KERN_ERR PREFIX
				  "Error reading fan power state\n");
		return result;
	}

	device->flags.force_power_state = 1;
	acpi_bus_set_power(device->handle, power_state);
	device->flags.force_power_state = 0;

	return result;
}

static int __init acpi_fan_init(void)
{
	int result = 0;


#ifdef CONFIG_ACPI_PROCFS
	acpi_fan_dir = proc_mkdir(ACPI_FAN_CLASS, acpi_root_dir);
	if (!acpi_fan_dir)
		return -ENODEV;
#endif

	result = acpi_bus_register_driver(&acpi_fan_driver);
	if (result < 0) {
		remove_proc_entry(ACPI_FAN_CLASS, acpi_root_dir);
		return -ENODEV;
	}

	return 0;
}

static void __exit acpi_fan_exit(void)
{

	acpi_bus_unregister_driver(&acpi_fan_driver);

	remove_proc_entry(ACPI_FAN_CLASS, acpi_root_dir);

	return;
}

module_init(acpi_fan_init);
module_exit(acpi_fan_exit);