SUNRPC: Fix a potential race in rpc_wake_up_task()
[linux-2.6/mini2440.git] / drivers / acpi / fan.c
blob045c89477e59b2929f125ac536226928e949a73a
1 /*
2 * acpi_fan.c - ACPI Fan Driver ($Revision: 29 $)
4 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
5 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
7 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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.
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.
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.
23 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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>
34 #include <acpi/acpi_bus.h>
35 #include <acpi/acpi_drivers.h>
37 #define ACPI_FAN_COMPONENT 0x00200000
38 #define ACPI_FAN_CLASS "fan"
39 #define ACPI_FAN_DRIVER_NAME "ACPI Fan Driver"
40 #define ACPI_FAN_FILE_STATE "state"
42 #define _COMPONENT ACPI_FAN_COMPONENT
43 ACPI_MODULE_NAME("acpi_fan")
45 MODULE_AUTHOR("Paul Diefenbaugh");
46 MODULE_DESCRIPTION(ACPI_FAN_DRIVER_NAME);
47 MODULE_LICENSE("GPL");
49 static int acpi_fan_add(struct acpi_device *device);
50 static int acpi_fan_remove(struct acpi_device *device, int type);
51 static int acpi_fan_suspend(struct acpi_device *device, int state);
52 static int acpi_fan_resume(struct acpi_device *device, int state);
54 static struct acpi_driver acpi_fan_driver = {
55 .name = ACPI_FAN_DRIVER_NAME,
56 .class = ACPI_FAN_CLASS,
57 .ids = "PNP0C0B",
58 .ops = {
59 .add = acpi_fan_add,
60 .remove = acpi_fan_remove,
61 .suspend = acpi_fan_suspend,
62 .resume = acpi_fan_resume,
66 struct acpi_fan {
67 struct acpi_device * device;
70 /* --------------------------------------------------------------------------
71 FS Interface (/proc)
72 -------------------------------------------------------------------------- */
74 static struct proc_dir_entry *acpi_fan_dir;
76 static int acpi_fan_read_state(struct seq_file *seq, void *offset)
78 struct acpi_fan *fan = seq->private;
79 int state = 0;
82 if (fan) {
83 if (acpi_bus_get_power(fan->device->handle, &state))
84 seq_printf(seq, "status: ERROR\n");
85 else
86 seq_printf(seq, "status: %s\n",
87 !state ? "on" : "off");
89 return 0;
92 static int acpi_fan_state_open_fs(struct inode *inode, struct file *file)
94 return single_open(file, acpi_fan_read_state, PDE(inode)->data);
97 static ssize_t
98 acpi_fan_write_state(struct file *file, const char __user * buffer,
99 size_t count, loff_t * ppos)
101 int result = 0;
102 struct seq_file *m = (struct seq_file *)file->private_data;
103 struct acpi_fan *fan = (struct acpi_fan *)m->private;
104 char state_string[12] = { '\0' };
107 if (!fan || (count > sizeof(state_string) - 1))
108 return -EINVAL;
110 if (copy_from_user(state_string, buffer, count))
111 return -EFAULT;
113 state_string[count] = '\0';
115 result = acpi_bus_set_power(fan->device->handle,
116 simple_strtoul(state_string, NULL, 0));
117 if (result)
118 return result;
120 return count;
123 static const struct file_operations acpi_fan_state_ops = {
124 .open = acpi_fan_state_open_fs,
125 .read = seq_read,
126 .write = acpi_fan_write_state,
127 .llseek = seq_lseek,
128 .release = single_release,
129 .owner = THIS_MODULE,
132 static int acpi_fan_add_fs(struct acpi_device *device)
134 struct proc_dir_entry *entry = NULL;
137 if (!device)
138 return -EINVAL;
140 if (!acpi_device_dir(device)) {
141 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
142 acpi_fan_dir);
143 if (!acpi_device_dir(device))
144 return -ENODEV;
145 acpi_device_dir(device)->owner = THIS_MODULE;
148 /* 'status' [R/W] */
149 entry = create_proc_entry(ACPI_FAN_FILE_STATE,
150 S_IFREG | S_IRUGO | S_IWUSR,
151 acpi_device_dir(device));
152 if (!entry)
153 return -ENODEV;
154 else {
155 entry->proc_fops = &acpi_fan_state_ops;
156 entry->data = acpi_driver_data(device);
157 entry->owner = THIS_MODULE;
160 return 0;
163 static int acpi_fan_remove_fs(struct acpi_device *device)
166 if (acpi_device_dir(device)) {
167 remove_proc_entry(ACPI_FAN_FILE_STATE, acpi_device_dir(device));
168 remove_proc_entry(acpi_device_bid(device), acpi_fan_dir);
169 acpi_device_dir(device) = NULL;
172 return 0;
175 /* --------------------------------------------------------------------------
176 Driver Interface
177 -------------------------------------------------------------------------- */
179 static int acpi_fan_add(struct acpi_device *device)
181 int result = 0;
182 struct acpi_fan *fan = NULL;
183 int state = 0;
186 if (!device)
187 return -EINVAL;
189 fan = kmalloc(sizeof(struct acpi_fan), GFP_KERNEL);
190 if (!fan)
191 return -ENOMEM;
192 memset(fan, 0, sizeof(struct acpi_fan));
194 fan->device = device;
195 strcpy(acpi_device_name(device), "Fan");
196 strcpy(acpi_device_class(device), ACPI_FAN_CLASS);
197 acpi_driver_data(device) = fan;
199 result = acpi_bus_get_power(device->handle, &state);
200 if (result) {
201 printk(KERN_ERR PREFIX "Reading power state\n");
202 goto end;
205 device->flags.force_power_state = 1;
206 acpi_bus_set_power(device->handle, state);
207 device->flags.force_power_state = 0;
209 result = acpi_fan_add_fs(device);
210 if (result)
211 goto end;
213 printk(KERN_INFO PREFIX "%s [%s] (%s)\n",
214 acpi_device_name(device), acpi_device_bid(device),
215 !device->power.state ? "on" : "off");
217 end:
218 if (result)
219 kfree(fan);
221 return result;
224 static int acpi_fan_remove(struct acpi_device *device, int type)
226 struct acpi_fan *fan = NULL;
229 if (!device || !acpi_driver_data(device))
230 return -EINVAL;
232 fan = (struct acpi_fan *)acpi_driver_data(device);
234 acpi_fan_remove_fs(device);
236 kfree(fan);
238 return 0;
241 static int acpi_fan_suspend(struct acpi_device *device, int state)
243 if (!device)
244 return -EINVAL;
246 acpi_bus_set_power(device->handle, ACPI_STATE_D0);
248 return AE_OK;
251 static int acpi_fan_resume(struct acpi_device *device, int state)
253 int result = 0;
254 int power_state = 0;
256 if (!device)
257 return -EINVAL;
259 result = acpi_bus_get_power(device->handle, &power_state);
260 if (result) {
261 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
262 "Error reading fan power state\n"));
263 return result;
266 device->flags.force_power_state = 1;
267 acpi_bus_set_power(device->handle, power_state);
268 device->flags.force_power_state = 0;
270 return result;
273 static int __init acpi_fan_init(void)
275 int result = 0;
278 acpi_fan_dir = proc_mkdir(ACPI_FAN_CLASS, acpi_root_dir);
279 if (!acpi_fan_dir)
280 return -ENODEV;
281 acpi_fan_dir->owner = THIS_MODULE;
283 result = acpi_bus_register_driver(&acpi_fan_driver);
284 if (result < 0) {
285 remove_proc_entry(ACPI_FAN_CLASS, acpi_root_dir);
286 return -ENODEV;
289 return 0;
292 static void __exit acpi_fan_exit(void)
295 acpi_bus_unregister_driver(&acpi_fan_driver);
297 remove_proc_entry(ACPI_FAN_CLASS, acpi_root_dir);
299 return;
302 module_init(acpi_fan_init);
303 module_exit(acpi_fan_exit);