drivers/acpi/fan.c

   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 <asm/uaccess.h>
  31 #include <linux/thermal.h>
  32 #include <acpi/acpi_bus.h>
  33 #include <acpi/acpi_drivers.h>
  34
  35 #define PREFIX "ACPI: "
  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
  50 static const struct acpi_device_id fan_device_ids[] = {
  51         {"PNP0C0B", 0},
  52         {"", 0},
  53 };
  54 MODULE_DEVICE_TABLE(acpi, fan_device_ids);
  55
  56 static int acpi_fan_suspend(struct device *dev);
  57 static int acpi_fan_resume(struct device *dev);
  58 static SIMPLE_DEV_PM_OPS(acpi_fan_pm, acpi_fan_suspend, acpi_fan_resume);
  59
  60 static struct acpi_driver acpi_fan_driver = {
  61         .name = "fan",
  62         .class = ACPI_FAN_CLASS,
  63         .ids = fan_device_ids,
  64         .ops = {
  65                 .add = acpi_fan_add,
  66                 .remove = acpi_fan_remove,
  67                 },
  68         .drv.pm = &acpi_fan_pm,
  69 };
  70
  71 /* thermal cooling device callbacks */
  72 static int fan_get_max_state(struct thermal_cooling_device *cdev, unsigned long
  73                              *state)
  74 {
  75         /* ACPI fan device only support two states: ON/OFF */
  76         *state = 1;
  77         return 0;
  78 }
  79
  80 static int fan_get_cur_state(struct thermal_cooling_device *cdev, unsigned long
  81                              *state)
  82 {
  83         struct acpi_device *device = cdev->devdata;
  84         int result;
  85         int acpi_state;
  86
  87         if (!device)
  88                 return -EINVAL;
  89
  90         result = acpi_bus_update_power(device->handle, &acpi_state);
  91         if (result)
  92                 return result;
  93
  94         *state = (acpi_state == ACPI_STATE_D3 ? 0 :
  95                  (acpi_state == ACPI_STATE_D0 ? 1 : -1));
  96         return 0;
  97 }
  98
  99 static int
 100 fan_set_cur_state(struct thermal_cooling_device *cdev, unsigned long state)
 101 {
 102         struct acpi_device *device = cdev->devdata;
 103         int result;
 104
 105         if (!device || (state != 0 && state != 1))
 106                 return -EINVAL;
 107
 108         result = acpi_bus_set_power(device->handle,
 109                                 state ? ACPI_STATE_D0 : ACPI_STATE_D3);
 110
 111         return result;
 112 }
 113
 114 static const struct thermal_cooling_device_ops fan_cooling_ops = {
 115         .get_max_state = fan_get_max_state,
 116         .get_cur_state = fan_get_cur_state,
 117         .set_cur_state = fan_set_cur_state,
 118 };
 119
 120 /* --------------------------------------------------------------------------
 121                                  Driver Interface
 122    -------------------------------------------------------------------------- */
 123
 124 static int acpi_fan_add(struct acpi_device *device)
 125 {
 126         int result = 0;
 127         struct thermal_cooling_device *cdev;
 128
 129         if (!device)
 130                 return -EINVAL;
 131
 132         strcpy(acpi_device_name(device), "Fan");
 133         strcpy(acpi_device_class(device), ACPI_FAN_CLASS);
 134
 135         result = acpi_bus_update_power(device->handle, NULL);
 136         if (result) {
 137                 printk(KERN_ERR PREFIX "Setting initial power state\n");
 138                 goto end;
 139         }
 140
 141         cdev = thermal_cooling_device_register("Fan", device,
 142                                                 &fan_cooling_ops);
 143         if (IS_ERR(cdev)) {
 144                 result = PTR_ERR(cdev);
 145                 goto end;
 146         }
 147
 148         dev_dbg(&device->dev, "registered as cooling_device%d\n", cdev->id);
 149
 150         device->driver_data = cdev;
 151         result = sysfs_create_link(&device->dev.kobj,
 152                                    &cdev->device.kobj,
 153                                    "thermal_cooling");
 154         if (result)
 155                 dev_err(&device->dev, "Failed to create sysfs link "
 156                         "'thermal_cooling'\n");
 157
 158         result = sysfs_create_link(&cdev->device.kobj,
 159                                    &device->dev.kobj,
 160                                    "device");
 161         if (result)
 162                 dev_err(&device->dev, "Failed to create sysfs link "
 163                         "'device'\n");
 164
 165         printk(KERN_INFO PREFIX "%s [%s] (%s)\n",
 166                acpi_device_name(device), acpi_device_bid(device),
 167                !device->power.state ? "on" : "off");
 168
 169       end:
 170         return result;
 171 }
 172
 173 static int acpi_fan_remove(struct acpi_device *device, int type)
 174 {
 175         struct thermal_cooling_device *cdev = acpi_driver_data(device);
 176
 177         if (!device || !cdev)
 178                 return -EINVAL;
 179
 180         sysfs_remove_link(&device->dev.kobj, "thermal_cooling");
 181         sysfs_remove_link(&cdev->device.kobj, "device");
 182         thermal_cooling_device_unregister(cdev);
 183
 184         return 0;
 185 }
 186
 187 static int acpi_fan_suspend(struct device *dev)
 188 {
 189         if (!dev)
 190                 return -EINVAL;
 191
 192         acpi_bus_set_power(to_acpi_device(dev)->handle, ACPI_STATE_D0);
 193
 194         return AE_OK;
 195 }
 196
 197 static int acpi_fan_resume(struct device *dev)
 198 {
 199         int result;
 200
 201         if (!dev)
 202                 return -EINVAL;
 203
 204         result = acpi_bus_update_power(to_acpi_device(dev)->handle, NULL);
 205         if (result)
 206                 printk(KERN_ERR PREFIX "Error updating fan power state\n");
 207
 208         return result;
 209 }
 210
 211 static int __init acpi_fan_init(void)
 212 {
 213         int result = 0;
 214
 215         result = acpi_bus_register_driver(&acpi_fan_driver);
 216         if (result < 0)
 217                 return -ENODEV;
 218
 219         return 0;
 220 }
 221
 222 static void __exit acpi_fan_exit(void)
 223 {
 224
 225         acpi_bus_unregister_driver(&acpi_fan_driver);
 226
 227         return;
 228 }
 229
 230 module_init(acpi_fan_init);
 231 module_exit(acpi_fan_exit);