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 <linux/acpi.h>
  33
  34 #define PREFIX "ACPI: "
  35
  36 #define ACPI_FAN_CLASS                  "fan"
  37 #define ACPI_FAN_FILE_STATE             "state"
  38
  39 #define _COMPONENT              ACPI_FAN_COMPONENT
  40 ACPI_MODULE_NAME("fan");
  41
  42 MODULE_AUTHOR("Paul Diefenbaugh");
  43 MODULE_DESCRIPTION("ACPI Fan Driver");
  44 MODULE_LICENSE("GPL");
  45
  46 static int acpi_fan_add(struct acpi_device *device);
  47 static int acpi_fan_remove(struct acpi_device *device);
  48
  49 static const struct acpi_device_id fan_device_ids[] = {
  50         {"PNP0C0B", 0},
  51         {"", 0},
  52 };
  53 MODULE_DEVICE_TABLE(acpi, fan_device_ids);
  54
  55 #ifdef CONFIG_PM_SLEEP
  56 static int acpi_fan_suspend(struct device *dev);
  57 static int acpi_fan_resume(struct device *dev);
  58 #endif
  59 static SIMPLE_DEV_PM_OPS(acpi_fan_pm, acpi_fan_suspend, acpi_fan_resume);
  60
  61 static struct acpi_driver acpi_fan_driver = {
  62         .name = "fan",
  63         .class = ACPI_FAN_CLASS,
  64         .ids = fan_device_ids,
  65         .ops = {
  66                 .add = acpi_fan_add,
  67                 .remove = acpi_fan_remove,
  68                 },
  69         .drv.pm = &acpi_fan_pm,
  70 };
  71
  72 /* thermal cooling device callbacks */
  73 static int fan_get_max_state(struct thermal_cooling_device *cdev, unsigned long
  74                              *state)
  75 {
  76         /* ACPI fan device only support two states: ON/OFF */
  77         *state = 1;
  78         return 0;
  79 }
  80
  81 static int fan_get_cur_state(struct thermal_cooling_device *cdev, unsigned long
  82                              *state)
  83 {
  84         struct acpi_device *device = cdev->devdata;
  85         int result;
  86         int acpi_state = ACPI_STATE_D0;
  87
  88         if (!device)
  89                 return -EINVAL;
  90
  91         result = acpi_bus_update_power(device->handle, &acpi_state);
  92         if (result)
  93                 return result;
  94
  95         *state = (acpi_state == ACPI_STATE_D3_COLD ? 0 :
  96                  (acpi_state == ACPI_STATE_D0 ? 1 : -1));
  97         return 0;
  98 }
  99
 100 static int
 101 fan_set_cur_state(struct thermal_cooling_device *cdev, unsigned long state)
 102 {
 103         struct acpi_device *device = cdev->devdata;
 104         int result;
 105
 106         if (!device || (state != 0 && state != 1))
 107                 return -EINVAL;
 108
 109         result = acpi_bus_set_power(device->handle,
 110                                 state ? ACPI_STATE_D0 : ACPI_STATE_D3_COLD);
 111
 112         return result;
 113 }
 114
 115 static const struct thermal_cooling_device_ops fan_cooling_ops = {
 116         .get_max_state = fan_get_max_state,
 117         .get_cur_state = fan_get_cur_state,
 118         .set_cur_state = fan_set_cur_state,
 119 };
 120
 121 /* --------------------------------------------------------------------------
 122                                  Driver Interface
 123    -------------------------------------------------------------------------- */
 124
 125 static int acpi_fan_add(struct acpi_device *device)
 126 {
 127         int result = 0;
 128         struct thermal_cooling_device *cdev;
 129
 130         if (!device)
 131                 return -EINVAL;
 132
 133         strcpy(acpi_device_name(device), "Fan");
 134         strcpy(acpi_device_class(device), ACPI_FAN_CLASS);
 135
 136         result = acpi_bus_update_power(device->handle, NULL);
 137         if (result) {
 138                 printk(KERN_ERR PREFIX "Setting initial power state\n");
 139                 goto end;
 140         }
 141
 142         cdev = thermal_cooling_device_register("Fan", device,
 143                                                 &fan_cooling_ops);
 144         if (IS_ERR(cdev)) {
 145                 result = PTR_ERR(cdev);
 146                 goto end;
 147         }
 148
 149         dev_dbg(&device->dev, "registered as cooling_device%d\n", cdev->id);
 150
 151         device->driver_data = cdev;
 152         result = sysfs_create_link(&device->dev.kobj,
 153                                    &cdev->device.kobj,
 154                                    "thermal_cooling");
 155         if (result)
 156                 dev_err(&device->dev, "Failed to create sysfs link "
 157                         "'thermal_cooling'\n");
 158
 159         result = sysfs_create_link(&cdev->device.kobj,
 160                                    &device->dev.kobj,
 161                                    "device");
 162         if (result)
 163                 dev_err(&device->dev, "Failed to create sysfs link "
 164                         "'device'\n");
 165
 166         printk(KERN_INFO PREFIX "%s [%s] (%s)\n",
 167                acpi_device_name(device), acpi_device_bid(device),
 168                !device->power.state ? "on" : "off");
 169
 170 end:
 171         return result;
 172 }
 173
 174 static int acpi_fan_remove(struct acpi_device *device)
 175 {
 176         struct thermal_cooling_device *cdev;
 177
 178         if (!device)
 179                 return -EINVAL;
 180
 181         cdev =  acpi_driver_data(device);
 182         if (!cdev)
 183                 return -EINVAL;
 184
 185         sysfs_remove_link(&device->dev.kobj, "thermal_cooling");
 186         sysfs_remove_link(&cdev->device.kobj, "device");
 187         thermal_cooling_device_unregister(cdev);
 188
 189         return 0;
 190 }
 191
 192 #ifdef CONFIG_PM_SLEEP
 193 static int acpi_fan_suspend(struct device *dev)
 194 {
 195         if (!dev)
 196                 return -EINVAL;
 197
 198         acpi_bus_set_power(to_acpi_device(dev)->handle, ACPI_STATE_D0);
 199
 200         return AE_OK;
 201 }
 202
 203 static int acpi_fan_resume(struct device *dev)
 204 {
 205         int result;
 206
 207         if (!dev)
 208                 return -EINVAL;
 209
 210         result = acpi_bus_update_power(to_acpi_device(dev)->handle, NULL);
 211         if (result)
 212                 printk(KERN_ERR PREFIX "Error updating fan power state\n");
 213
 214         return result;
 215 }
 216 #endif
 217
 218 module_acpi_driver(acpi_fan_driver);