gma500: Fix cdv warning on unused variable
[zen-stable.git] / drivers / acpi / fan.c
blob467479f07c1fd35932390cba80ffe90add0dba65
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 <asm/uaccess.h>
31 #include <linux/thermal.h>
32 #include <acpi/acpi_bus.h>
33 #include <acpi/acpi_drivers.h>
35 #define PREFIX "ACPI: "
37 #define ACPI_FAN_CLASS "fan"
38 #define ACPI_FAN_FILE_STATE "state"
40 #define _COMPONENT ACPI_FAN_COMPONENT
41 ACPI_MODULE_NAME("fan");
43 MODULE_AUTHOR("Paul Diefenbaugh");
44 MODULE_DESCRIPTION("ACPI Fan Driver");
45 MODULE_LICENSE("GPL");
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);
52 static const struct acpi_device_id fan_device_ids[] = {
53 {"PNP0C0B", 0},
54 {"", 0},
56 MODULE_DEVICE_TABLE(acpi, fan_device_ids);
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,
70 /* thermal cooling device callbacks */
71 static int fan_get_max_state(struct thermal_cooling_device *cdev, unsigned long
72 *state)
74 /* ACPI fan device only support two states: ON/OFF */
75 *state = 1;
76 return 0;
79 static int fan_get_cur_state(struct thermal_cooling_device *cdev, unsigned long
80 *state)
82 struct acpi_device *device = cdev->devdata;
83 int result;
84 int acpi_state;
86 if (!device)
87 return -EINVAL;
89 result = acpi_bus_update_power(device->handle, &acpi_state);
90 if (result)
91 return result;
93 *state = (acpi_state == ACPI_STATE_D3 ? 0 :
94 (acpi_state == ACPI_STATE_D0 ? 1 : -1));
95 return 0;
98 static int
99 fan_set_cur_state(struct thermal_cooling_device *cdev, unsigned long state)
101 struct acpi_device *device = cdev->devdata;
102 int result;
104 if (!device || (state != 0 && state != 1))
105 return -EINVAL;
107 result = acpi_bus_set_power(device->handle,
108 state ? ACPI_STATE_D0 : ACPI_STATE_D3);
110 return result;
113 static struct thermal_cooling_device_ops fan_cooling_ops = {
114 .get_max_state = fan_get_max_state,
115 .get_cur_state = fan_get_cur_state,
116 .set_cur_state = fan_set_cur_state,
119 /* --------------------------------------------------------------------------
120 Driver Interface
121 -------------------------------------------------------------------------- */
123 static int acpi_fan_add(struct acpi_device *device)
125 int result = 0;
126 struct thermal_cooling_device *cdev;
128 if (!device)
129 return -EINVAL;
131 strcpy(acpi_device_name(device), "Fan");
132 strcpy(acpi_device_class(device), ACPI_FAN_CLASS);
134 result = acpi_bus_update_power(device->handle, NULL);
135 if (result) {
136 printk(KERN_ERR PREFIX "Setting initial power state\n");
137 goto end;
140 cdev = thermal_cooling_device_register("Fan", device,
141 &fan_cooling_ops);
142 if (IS_ERR(cdev)) {
143 result = PTR_ERR(cdev);
144 goto end;
147 dev_dbg(&device->dev, "registered as cooling_device%d\n", cdev->id);
149 device->driver_data = cdev;
150 result = sysfs_create_link(&device->dev.kobj,
151 &cdev->device.kobj,
152 "thermal_cooling");
153 if (result)
154 dev_err(&device->dev, "Failed to create sysfs link "
155 "'thermal_cooling'\n");
157 result = sysfs_create_link(&cdev->device.kobj,
158 &device->dev.kobj,
159 "device");
160 if (result)
161 dev_err(&device->dev, "Failed to create sysfs link "
162 "'device'\n");
164 printk(KERN_INFO PREFIX "%s [%s] (%s)\n",
165 acpi_device_name(device), acpi_device_bid(device),
166 !device->power.state ? "on" : "off");
168 end:
169 return result;
172 static int acpi_fan_remove(struct acpi_device *device, int type)
174 struct thermal_cooling_device *cdev = acpi_driver_data(device);
176 if (!device || !cdev)
177 return -EINVAL;
179 sysfs_remove_link(&device->dev.kobj, "thermal_cooling");
180 sysfs_remove_link(&cdev->device.kobj, "device");
181 thermal_cooling_device_unregister(cdev);
183 return 0;
186 static int acpi_fan_suspend(struct acpi_device *device, pm_message_t state)
188 if (!device)
189 return -EINVAL;
191 acpi_bus_set_power(device->handle, ACPI_STATE_D0);
193 return AE_OK;
196 static int acpi_fan_resume(struct acpi_device *device)
198 int result;
200 if (!device)
201 return -EINVAL;
203 result = acpi_bus_update_power(device->handle, NULL);
204 if (result)
205 printk(KERN_ERR PREFIX "Error updating fan power state\n");
207 return result;
210 static int __init acpi_fan_init(void)
212 int result = 0;
214 result = acpi_bus_register_driver(&acpi_fan_driver);
215 if (result < 0)
216 return -ENODEV;
218 return 0;
221 static void __exit acpi_fan_exit(void)
224 acpi_bus_unregister_driver(&acpi_fan_driver);
226 return;
229 module_init(acpi_fan_init);
230 module_exit(acpi_fan_exit);