1/*
2 *  acpi_fan.c - ACPI Fan Driver ($Revision: 1.1.1.1 $)
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#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
42ACPI_MODULE_NAME("fan");
43
44MODULE_AUTHOR("Paul Diefenbaugh");
45MODULE_DESCRIPTION("ACPI Fan Driver");
46MODULE_LICENSE("GPL");
47
48static int acpi_fan_add(struct acpi_device *device);
49static int acpi_fan_remove(struct acpi_device *device, int type);
50static int acpi_fan_suspend(struct acpi_device *device, pm_message_t state);
51static int acpi_fan_resume(struct acpi_device *device);
52
53static struct acpi_driver acpi_fan_driver = {
54	.name = "fan",
55	.class = ACPI_FAN_CLASS,
56	.ids = "PNP0C0B",
57	.ops = {
58		.add = acpi_fan_add,
59		.remove = acpi_fan_remove,
60		.suspend = acpi_fan_suspend,
61		.resume = acpi_fan_resume,
62		},
63};
64
65struct acpi_fan {
66	struct acpi_device * device;
67};
68
69/* --------------------------------------------------------------------------
70                              FS Interface (/proc)
71   -------------------------------------------------------------------------- */
72
73static struct proc_dir_entry *acpi_fan_dir;
74
75static int acpi_fan_read_state(struct seq_file *seq, void *offset)
76{
77	struct acpi_fan *fan = seq->private;
78	int state = 0;
79
80
81	if (fan) {
82		if (acpi_bus_get_power(fan->device->handle, &state))
83			seq_printf(seq, "status:                  ERROR\n");
84		else
85			seq_printf(seq, "status:                  %s\n",
86				   !state ? "on" : "off");
87	}
88	return 0;
89}
90
91static int acpi_fan_state_open_fs(struct inode *inode, struct file *file)
92{
93	return single_open(file, acpi_fan_read_state, PDE(inode)->data);
94}
95
96static ssize_t
97acpi_fan_write_state(struct file *file, const char __user * buffer,
98		     size_t count, loff_t * ppos)
99{
100	int result = 0;
101	struct seq_file *m = file->private_data;
102	struct acpi_fan *fan = m->private;
103	char state_string[12] = { '\0' };
104
105
106	if (!fan || (count > sizeof(state_string) - 1))
107		return -EINVAL;
108
109	if (copy_from_user(state_string, buffer, count))
110		return -EFAULT;
111
112	state_string[count] = '\0';
113
114	result = acpi_bus_set_power(fan->device->handle,
115				    simple_strtoul(state_string, NULL, 0));
116	if (result)
117		return result;
118
119	return count;
120}
121
122static const struct file_operations acpi_fan_state_ops = {
123	.open = acpi_fan_state_open_fs,
124	.read = seq_read,
125	.write = acpi_fan_write_state,
126	.llseek = seq_lseek,
127	.release = single_release,
128	.owner = THIS_MODULE,
129};
130
131static int acpi_fan_add_fs(struct acpi_device *device)
132{
133	struct proc_dir_entry *entry = NULL;
134
135
136	if (!device)
137		return -EINVAL;
138
139	if (!acpi_device_dir(device)) {
140		acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
141						     acpi_fan_dir);
142		if (!acpi_device_dir(device))
143			return -ENODEV;
144		acpi_device_dir(device)->owner = THIS_MODULE;
145	}
146
147	/* 'status' [R/W] */
148	entry = create_proc_entry(ACPI_FAN_FILE_STATE,
149				  S_IFREG | S_IRUGO | S_IWUSR,
150				  acpi_device_dir(device));
151	if (!entry)
152		return -ENODEV;
153	else {
154		entry->proc_fops = &acpi_fan_state_ops;
155		entry->data = acpi_driver_data(device);
156		entry->owner = THIS_MODULE;
157	}
158
159	return 0;
160}
161
162static int acpi_fan_remove_fs(struct acpi_device *device)
163{
164
165	if (acpi_device_dir(device)) {
166		remove_proc_entry(ACPI_FAN_FILE_STATE, acpi_device_dir(device));
167		remove_proc_entry(acpi_device_bid(device), acpi_fan_dir);
168		acpi_device_dir(device) = NULL;
169	}
170
171	return 0;
172}
173
174/* --------------------------------------------------------------------------
175                                 Driver Interface
176   -------------------------------------------------------------------------- */
177
178static int acpi_fan_add(struct acpi_device *device)
179{
180	int result = 0;
181	struct acpi_fan *fan = NULL;
182	int state = 0;
183
184
185	if (!device)
186		return -EINVAL;
187
188	fan = kzalloc(sizeof(struct acpi_fan), GFP_KERNEL);
189	if (!fan)
190		return -ENOMEM;
191
192	fan->device = device;
193	strcpy(acpi_device_name(device), "Fan");
194	strcpy(acpi_device_class(device), ACPI_FAN_CLASS);
195	acpi_driver_data(device) = fan;
196
197	result = acpi_bus_get_power(device->handle, &state);
198	if (result) {
199		printk(KERN_ERR PREFIX "Reading power state\n");
200		goto end;
201	}
202
203	device->flags.force_power_state = 1;
204	acpi_bus_set_power(device->handle, state);
205	device->flags.force_power_state = 0;
206
207	result = acpi_fan_add_fs(device);
208	if (result)
209		goto end;
210
211	printk(KERN_INFO PREFIX "%s [%s] (%s)\n",
212	       acpi_device_name(device), acpi_device_bid(device),
213	       !device->power.state ? "on" : "off");
214
215      end:
216	if (result)
217		kfree(fan);
218
219	return result;
220}
221
222static int acpi_fan_remove(struct acpi_device *device, int type)
223{
224	struct acpi_fan *fan = NULL;
225
226
227	if (!device || !acpi_driver_data(device))
228		return -EINVAL;
229
230	fan = acpi_driver_data(device);
231
232	acpi_fan_remove_fs(device);
233
234	kfree(fan);
235
236	return 0;
237}
238
239static int acpi_fan_suspend(struct acpi_device *device, pm_message_t state)
240{
241	if (!device)
242		return -EINVAL;
243
244	acpi_bus_set_power(device->handle, ACPI_STATE_D0);
245
246	return AE_OK;
247}
248
249static int acpi_fan_resume(struct acpi_device *device)
250{
251	int result = 0;
252	int power_state = 0;
253
254	if (!device)
255		return -EINVAL;
256
257	result = acpi_bus_get_power(device->handle, &power_state);
258	if (result) {
259		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
260				  "Error reading fan power state\n"));
261		return result;
262	}
263
264	device->flags.force_power_state = 1;
265	acpi_bus_set_power(device->handle, power_state);
266	device->flags.force_power_state = 0;
267
268	return result;
269}
270
271static int __init acpi_fan_init(void)
272{
273	int result = 0;
274
275
276	acpi_fan_dir = proc_mkdir(ACPI_FAN_CLASS, acpi_root_dir);
277	if (!acpi_fan_dir)
278		return -ENODEV;
279	acpi_fan_dir->owner = THIS_MODULE;
280
281	result = acpi_bus_register_driver(&acpi_fan_driver);
282	if (result < 0) {
283		remove_proc_entry(ACPI_FAN_CLASS, acpi_root_dir);
284		return -ENODEV;
285	}
286
287	return 0;
288}
289
290static void __exit acpi_fan_exit(void)
291{
292
293	acpi_bus_unregister_driver(&acpi_fan_driver);
294
295	remove_proc_entry(ACPI_FAN_CLASS, acpi_root_dir);
296
297	return;
298}
299
300module_init(acpi_fan_init);
301module_exit(acpi_fan_exit);
302