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 static int acpi_fan_suspend(struct acpi_device *device, pm_message_t state);
  50 static int acpi_fan_resume(struct acpi_device *device);
  51
  52 static const struct acpi_device_id fan_device_ids[] = {
  53         {"PNP0C0B", 0},
  54         {"", 0},
  55 };
  56 MODULE_DEVICE_TABLE(acpi, fan_device_ids);
  57
  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,
  67                 },
  68 };
  69
  70 /* thermal cooling device callbacks */
  71 static int fan_get_max_state(struct thermal_cooling_device *cdev, unsigned long
  72                              *state)
  73 {
  74         /* ACPI fan device only support two states: ON/OFF */
  75         *state = 1;
  76         return 0;
  77 }
  78
  79 static int fan_get_cur_state(struct thermal_cooling_device *cdev, unsigned long
  80                              *state)
  81 {
  82         struct acpi_device *device = cdev->devdata;
  83         int result;
  84         int acpi_state;
  85
  86         if (!device)
  87                 return -EINVAL;
  88
  89         result = acpi_bus_get_power(device->handle, &acpi_state);
  90         if (result)
  91                 return result;
  92
  93         *state = (acpi_state == ACPI_STATE_D3 ? 0 :
  94                  (acpi_state == ACPI_STATE_D0 ? 1 : -1));
  95         return 0;
  96 }
  97
  98 static int
  99 fan_set_cur_state(struct thermal_cooling_device *cdev, unsigned long state)
 100 {
 101         struct acpi_device *device = cdev->devdata;
 102         int result;
 103
 104         if (!device || (state != 0 && state != 1))
 105                 return -EINVAL;
 106
 107         result = acpi_bus_set_power(device->handle,
 108                                 state ? ACPI_STATE_D0 : ACPI_STATE_D3);
 109
 110         return result;
 111 }
 112
 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,
 117 };
 118
 119 /* --------------------------------------------------------------------------
 120                                  Driver Interface
 121    -------------------------------------------------------------------------- */
 122
 123 static int acpi_fan_add(struct acpi_device *device)
 124 {
 125         int result = 0;
 126         int state = 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_get_power(device->handle, &state);
 136         if (result) {
 137                 printk(KERN_ERR PREFIX "Reading power state\n");
 138                 goto end;
 139         }
 140
 141         device->flags.force_power_state = 1;
 142         acpi_bus_set_power(device->handle, state);
 143         device->flags.force_power_state = 0;
 144
 145         cdev = thermal_cooling_device_register("Fan", device,
 146                                                 &fan_cooling_ops);
 147         if (IS_ERR(cdev)) {
 148                 result = PTR_ERR(cdev);
 149                 goto end;
 150         }
 151
 152         dev_dbg(&device->dev, "registered as cooling_device%d\n", cdev->id);
 153
 154         device->driver_data = cdev;
 155         result = sysfs_create_link(&device->dev.kobj,
 156                                    &cdev->device.kobj,
 157                                    "thermal_cooling");
 158         if (result)
 159                 dev_err(&device->dev, "Failed to create sysfs link "
 160                         "'thermal_cooling'\n");
 161
 162         result = sysfs_create_link(&cdev->device.kobj,
 163                                    &device->dev.kobj,
 164                                    "device");
 165         if (result)
 166                 dev_err(&device->dev, "Failed to create sysfs link "
 167                         "'device'\n");
 168
 169         printk(KERN_INFO PREFIX "%s [%s] (%s)\n",
 170                acpi_device_name(device), acpi_device_bid(device),
 171                !device->power.state ? "on" : "off");
 172
 173       end:
 174         return result;
 175 }
 176
 177 static int acpi_fan_remove(struct acpi_device *device, int type)
 178 {
 179         struct thermal_cooling_device *cdev = acpi_driver_data(device);
 180
 181         if (!device || !cdev)
 182                 return -EINVAL;
 183
 184         sysfs_remove_link(&device->dev.kobj, "thermal_cooling");
 185         sysfs_remove_link(&cdev->device.kobj, "device");
 186         thermal_cooling_device_unregister(cdev);
 187
 188         return 0;
 189 }
 190
 191 static int acpi_fan_suspend(struct acpi_device *device, pm_message_t state)
 192 {
 193         if (!device)
 194                 return -EINVAL;
 195
 196         acpi_bus_set_power(device->handle, ACPI_STATE_D0);
 197
 198         return AE_OK;
 199 }
 200
 201 static int acpi_fan_resume(struct acpi_device *device)
 202 {
 203         int result = 0;
 204         int power_state = 0;
 205
 206         if (!device)
 207                 return -EINVAL;
 208
 209         result = acpi_bus_get_power(device->handle, &power_state);
 210         if (result) {
 211                 printk(KERN_ERR PREFIX
 212                                   "Error reading fan power state\n");
 213                 return result;
 214         }
 215
 216         device->flags.force_power_state = 1;
 217         acpi_bus_set_power(device->handle, power_state);
 218         device->flags.force_power_state = 0;
 219
 220         return result;
 221 }
 222
 223 static int __init acpi_fan_init(void)
 224 {
 225         int result = 0;
 226
 227         result = acpi_bus_register_driver(&acpi_fan_driver);
 228         if (result < 0)
 229                 return -ENODEV;
 230
 231         return 0;
 232 }
 233
 234 static void __exit acpi_fan_exit(void)
 235 {
 236
 237         acpi_bus_unregister_driver(&acpi_fan_driver);
 238
 239         return;
 240 }
 241
 242 module_init(acpi_fan_init);
 243 module_exit(acpi_fan_exit);