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 <linux/proc_fs.h>
  31 #include <linux/seq_file.h>
  32 #include <asm/uaccess.h>
  33 #include <linux/thermal.h>
  34 #include <acpi/acpi_bus.h>
  35 #include <acpi/acpi_drivers.h>
  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                               FS Interface (/proc)
 121    -------------------------------------------------------------------------- */
 122 #ifdef CONFIG_ACPI_PROCFS
 123
 124 static struct proc_dir_entry *acpi_fan_dir;
 125
 126 static int acpi_fan_read_state(struct seq_file *seq, void *offset)
 127 {
 128         struct acpi_device *device = seq->private;
 129         int state = 0;
 130
 131
 132         if (device) {
 133                 if (acpi_bus_get_power(device->handle, &state))
 134                         seq_printf(seq, "status:                  ERROR\n");
 135                 else
 136                         seq_printf(seq, "status:                  %s\n",
 137                                    !state ? "on" : "off");
 138         }
 139         return 0;
 140 }
 141
 142 static int acpi_fan_state_open_fs(struct inode *inode, struct file *file)
 143 {
 144         return single_open(file, acpi_fan_read_state, PDE(inode)->data);
 145 }
 146
 147 static ssize_t
 148 acpi_fan_write_state(struct file *file, const char __user * buffer,
 149                      size_t count, loff_t * ppos)
 150 {
 151         int result = 0;
 152         struct seq_file *m = file->private_data;
 153         struct acpi_device *device = m->private;
 154         char state_string[3] = { '\0' };
 155
 156         if (count > sizeof(state_string) - 1)
 157                 return -EINVAL;
 158
 159         if (copy_from_user(state_string, buffer, count))
 160                 return -EFAULT;
 161
 162         state_string[count] = '\0';
 163         if ((state_string[0] < '0') || (state_string[0] > '3'))
 164                 return -EINVAL;
 165         if (state_string[1] == '\n')
 166                 state_string[1] = '\0';
 167         if (state_string[1] != '\0')
 168                 return -EINVAL;
 169
 170         result = acpi_bus_set_power(device->handle,
 171                                     simple_strtoul(state_string, NULL, 0));
 172         if (result)
 173                 return result;
 174
 175         return count;
 176 }
 177
 178 static const struct file_operations acpi_fan_state_ops = {
 179         .open = acpi_fan_state_open_fs,
 180         .read = seq_read,
 181         .write = acpi_fan_write_state,
 182         .llseek = seq_lseek,
 183         .release = single_release,
 184         .owner = THIS_MODULE,
 185 };
 186
 187 static int acpi_fan_add_fs(struct acpi_device *device)
 188 {
 189         struct proc_dir_entry *entry = NULL;
 190
 191
 192         if (!device)
 193                 return -EINVAL;
 194
 195         if (!acpi_device_dir(device)) {
 196                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 197                                                      acpi_fan_dir);
 198                 if (!acpi_device_dir(device))
 199                         return -ENODEV;
 200         }
 201
 202         /* 'status' [R/W] */
 203         entry = proc_create_data(ACPI_FAN_FILE_STATE,
 204                                  S_IFREG | S_IRUGO | S_IWUSR,
 205                                  acpi_device_dir(device),
 206                                  &acpi_fan_state_ops,
 207                                  device);
 208         if (!entry)
 209                 return -ENODEV;
 210         return 0;
 211 }
 212
 213 static int acpi_fan_remove_fs(struct acpi_device *device)
 214 {
 215
 216         if (acpi_device_dir(device)) {
 217                 remove_proc_entry(ACPI_FAN_FILE_STATE, acpi_device_dir(device));
 218                 remove_proc_entry(acpi_device_bid(device), acpi_fan_dir);
 219                 acpi_device_dir(device) = NULL;
 220         }
 221
 222         return 0;
 223 }
 224 #else
 225 static int acpi_fan_add_fs(struct acpi_device *device)
 226 {
 227         return 0;
 228 }
 229
 230 static int acpi_fan_remove_fs(struct acpi_device *device)
 231 {
 232         return 0;
 233 }
 234 #endif
 235 /* --------------------------------------------------------------------------
 236                                  Driver Interface
 237    -------------------------------------------------------------------------- */
 238
 239 static int acpi_fan_add(struct acpi_device *device)
 240 {
 241         int result = 0;
 242         int state = 0;
 243         struct thermal_cooling_device *cdev;
 244
 245         if (!device)
 246                 return -EINVAL;
 247
 248         strcpy(acpi_device_name(device), "Fan");
 249         strcpy(acpi_device_class(device), ACPI_FAN_CLASS);
 250
 251         result = acpi_bus_get_power(device->handle, &state);
 252         if (result) {
 253                 printk(KERN_ERR PREFIX "Reading power state\n");
 254                 goto end;
 255         }
 256
 257         device->flags.force_power_state = 1;
 258         acpi_bus_set_power(device->handle, state);
 259         device->flags.force_power_state = 0;
 260
 261         cdev = thermal_cooling_device_register("Fan", device,
 262                                                 &fan_cooling_ops);
 263         if (IS_ERR(cdev)) {
 264                 result = PTR_ERR(cdev);
 265                 goto end;
 266         }
 267
 268         dev_info(&device->dev, "registered as cooling_device%d\n", cdev->id);
 269
 270         device->driver_data = cdev;
 271         result = sysfs_create_link(&device->dev.kobj,
 272                                    &cdev->device.kobj,
 273                                    "thermal_cooling");
 274         if (result)
 275                 dev_err(&device->dev, "Failed to create sysfs link "
 276                         "'thermal_cooling'\n");
 277
 278         result = sysfs_create_link(&cdev->device.kobj,
 279                                    &device->dev.kobj,
 280                                    "device");
 281         if (result)
 282                 dev_err(&device->dev, "Failed to create sysfs link "
 283                         "'device'\n");
 284
 285         result = acpi_fan_add_fs(device);
 286         if (result)
 287                 goto end;
 288
 289         printk(KERN_INFO PREFIX "%s [%s] (%s)\n",
 290                acpi_device_name(device), acpi_device_bid(device),
 291                !device->power.state ? "on" : "off");
 292
 293       end:
 294         return result;
 295 }
 296
 297 static int acpi_fan_remove(struct acpi_device *device, int type)
 298 {
 299         struct thermal_cooling_device *cdev = acpi_driver_data(device);
 300
 301         if (!device || !cdev)
 302                 return -EINVAL;
 303
 304         acpi_fan_remove_fs(device);
 305         sysfs_remove_link(&device->dev.kobj, "thermal_cooling");
 306         sysfs_remove_link(&cdev->device.kobj, "device");
 307         thermal_cooling_device_unregister(cdev);
 308
 309         return 0;
 310 }
 311
 312 static int acpi_fan_suspend(struct acpi_device *device, pm_message_t state)
 313 {
 314         if (!device)
 315                 return -EINVAL;
 316
 317         acpi_bus_set_power(device->handle, ACPI_STATE_D0);
 318
 319         return AE_OK;
 320 }
 321
 322 static int acpi_fan_resume(struct acpi_device *device)
 323 {
 324         int result = 0;
 325         int power_state = 0;
 326
 327         if (!device)
 328                 return -EINVAL;
 329
 330         result = acpi_bus_get_power(device->handle, &power_state);
 331         if (result) {
 332                 printk(KERN_ERR PREFIX
 333                                   "Error reading fan power state\n");
 334                 return result;
 335         }
 336
 337         device->flags.force_power_state = 1;
 338         acpi_bus_set_power(device->handle, power_state);
 339         device->flags.force_power_state = 0;
 340
 341         return result;
 342 }
 343
 344 static int __init acpi_fan_init(void)
 345 {
 346         int result = 0;
 347
 348
 349 #ifdef CONFIG_ACPI_PROCFS
 350         acpi_fan_dir = proc_mkdir(ACPI_FAN_CLASS, acpi_root_dir);
 351         if (!acpi_fan_dir)
 352                 return -ENODEV;
 353 #endif
 354
 355         result = acpi_bus_register_driver(&acpi_fan_driver);
 356         if (result < 0) {
 357                 remove_proc_entry(ACPI_FAN_CLASS, acpi_root_dir);
 358                 return -ENODEV;
 359         }
 360
 361         return 0;
 362 }
 363
 364 static void __exit acpi_fan_exit(void)
 365 {
 366
 367         acpi_bus_unregister_driver(&acpi_fan_driver);
 368
 369         remove_proc_entry(ACPI_FAN_CLASS, acpi_root_dir);
 370
 371         return;
 372 }
 373
 374 module_init(acpi_fan_init);
 375 module_exit(acpi_fan_exit);