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, char *buf)
  72 {
  73         /* ACPI fan device only support two states: ON/OFF */
  74         return sprintf(buf, "1\n");
  75 }
  76
  77 static int fan_get_cur_state(struct thermal_cooling_device *cdev, char *buf)
  78 {
  79         struct acpi_device *device = cdev->devdata;
  80         int state;
  81         int result;
  82
  83         if (!device)
  84                 return -EINVAL;
  85
  86         result = acpi_bus_get_power(device->handle, &state);
  87         if (result)
  88                 return result;
  89
  90         return sprintf(buf, "%s\n", state == ACPI_STATE_D3 ? "0" :
  91                          (state == ACPI_STATE_D0 ? "1" : "unknown"));
  92 }
  93
  94 static int
  95 fan_set_cur_state(struct thermal_cooling_device *cdev, unsigned int state)
  96 {
  97         struct acpi_device *device = cdev->devdata;
  98         int result;
  99
 100         if (!device || (state != 0 && state != 1))
 101                 return -EINVAL;
 102
 103         result = acpi_bus_set_power(device->handle,
 104                                 state ? ACPI_STATE_D0 : ACPI_STATE_D3);
 105
 106         return result;
 107 }
 108
 109 static struct thermal_cooling_device_ops fan_cooling_ops = {
 110         .get_max_state = fan_get_max_state,
 111         .get_cur_state = fan_get_cur_state,
 112         .set_cur_state = fan_set_cur_state,
 113 };
 114
 115 /* --------------------------------------------------------------------------
 116                               FS Interface (/proc)
 117    -------------------------------------------------------------------------- */
 118 #ifdef CONFIG_ACPI_PROCFS
 119
 120 static struct proc_dir_entry *acpi_fan_dir;
 121
 122 static int acpi_fan_read_state(struct seq_file *seq, void *offset)
 123 {
 124         struct acpi_device *device = seq->private;
 125         int state = 0;
 126
 127
 128         if (device) {
 129                 if (acpi_bus_get_power(device->handle, &state))
 130                         seq_printf(seq, "status:                  ERROR\n");
 131                 else
 132                         seq_printf(seq, "status:                  %s\n",
 133                                    !state ? "on" : "off");
 134         }
 135         return 0;
 136 }
 137
 138 static int acpi_fan_state_open_fs(struct inode *inode, struct file *file)
 139 {
 140         return single_open(file, acpi_fan_read_state, PDE(inode)->data);
 141 }
 142
 143 static ssize_t
 144 acpi_fan_write_state(struct file *file, const char __user * buffer,
 145                      size_t count, loff_t * ppos)
 146 {
 147         int result = 0;
 148         struct seq_file *m = file->private_data;
 149         struct acpi_device *device = m->private;
 150         char state_string[3] = { '\0' };
 151
 152         if (count > sizeof(state_string) - 1)
 153                 return -EINVAL;
 154
 155         if (copy_from_user(state_string, buffer, count))
 156                 return -EFAULT;
 157
 158         state_string[count] = '\0';
 159         if ((state_string[0] < '0') || (state_string[0] > '3'))
 160                 return -EINVAL;
 161         if (state_string[1] == '\n')
 162                 state_string[1] = '\0';
 163         if (state_string[1] != '\0')
 164                 return -EINVAL;
 165
 166         result = acpi_bus_set_power(device->handle,
 167                                     simple_strtoul(state_string, NULL, 0));
 168         if (result)
 169                 return result;
 170
 171         return count;
 172 }
 173
 174 static const struct file_operations acpi_fan_state_ops = {
 175         .open = acpi_fan_state_open_fs,
 176         .read = seq_read,
 177         .write = acpi_fan_write_state,
 178         .llseek = seq_lseek,
 179         .release = single_release,
 180         .owner = THIS_MODULE,
 181 };
 182
 183 static int acpi_fan_add_fs(struct acpi_device *device)
 184 {
 185         struct proc_dir_entry *entry = NULL;
 186
 187
 188         if (!device)
 189                 return -EINVAL;
 190
 191         if (!acpi_device_dir(device)) {
 192                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 193                                                      acpi_fan_dir);
 194                 if (!acpi_device_dir(device))
 195                         return -ENODEV;
 196         }
 197
 198         /* 'status' [R/W] */
 199         entry = proc_create_data(ACPI_FAN_FILE_STATE,
 200                                  S_IFREG | S_IRUGO | S_IWUSR,
 201                                  acpi_device_dir(device),
 202                                  &acpi_fan_state_ops,
 203                                  device);
 204         if (!entry)
 205                 return -ENODEV;
 206         return 0;
 207 }
 208
 209 static int acpi_fan_remove_fs(struct acpi_device *device)
 210 {
 211
 212         if (acpi_device_dir(device)) {
 213                 remove_proc_entry(ACPI_FAN_FILE_STATE, acpi_device_dir(device));
 214                 remove_proc_entry(acpi_device_bid(device), acpi_fan_dir);
 215                 acpi_device_dir(device) = NULL;
 216         }
 217
 218         return 0;
 219 }
 220 #else
 221 static int acpi_fan_add_fs(struct acpi_device *device)
 222 {
 223         return 0;
 224 }
 225
 226 static int acpi_fan_remove_fs(struct acpi_device *device)
 227 {
 228         return 0;
 229 }
 230 #endif
 231 /* --------------------------------------------------------------------------
 232                                  Driver Interface
 233    -------------------------------------------------------------------------- */
 234
 235 static int acpi_fan_add(struct acpi_device *device)
 236 {
 237         int result = 0;
 238         int state = 0;
 239         struct thermal_cooling_device *cdev;
 240
 241         if (!device)
 242                 return -EINVAL;
 243
 244         strcpy(acpi_device_name(device), "Fan");
 245         strcpy(acpi_device_class(device), ACPI_FAN_CLASS);
 246
 247         result = acpi_bus_get_power(device->handle, &state);
 248         if (result) {
 249                 printk(KERN_ERR PREFIX "Reading power state\n");
 250                 goto end;
 251         }
 252
 253         device->flags.force_power_state = 1;
 254         acpi_bus_set_power(device->handle, state);
 255         device->flags.force_power_state = 0;
 256
 257         cdev = thermal_cooling_device_register("Fan", device,
 258                                                 &fan_cooling_ops);
 259         if (IS_ERR(cdev)) {
 260                 result = PTR_ERR(cdev);
 261                 goto end;
 262         }
 263
 264         dev_info(&device->dev, "registered as cooling_device%d\n", cdev->id);
 265
 266         device->driver_data = cdev;
 267         result = sysfs_create_link(&device->dev.kobj,
 268                                    &cdev->device.kobj,
 269                                    "thermal_cooling");
 270         if (result)
 271                 dev_err(&device->dev, "Failed to create sysfs link "
 272                         "'thermal_cooling'\n");
 273
 274         result = sysfs_create_link(&cdev->device.kobj,
 275                                    &device->dev.kobj,
 276                                    "device");
 277         if (result)
 278                 dev_err(&device->dev, "Failed to create sysfs link "
 279                         "'device'\n");
 280
 281         result = acpi_fan_add_fs(device);
 282         if (result)
 283                 goto end;
 284
 285         printk(KERN_INFO PREFIX "%s [%s] (%s)\n",
 286                acpi_device_name(device), acpi_device_bid(device),
 287                !device->power.state ? "on" : "off");
 288
 289       end:
 290         return result;
 291 }
 292
 293 static int acpi_fan_remove(struct acpi_device *device, int type)
 294 {
 295         struct thermal_cooling_device *cdev = acpi_driver_data(device);
 296
 297         if (!device || !cdev)
 298                 return -EINVAL;
 299
 300         acpi_fan_remove_fs(device);
 301         sysfs_remove_link(&device->dev.kobj, "thermal_cooling");
 302         sysfs_remove_link(&cdev->device.kobj, "device");
 303         thermal_cooling_device_unregister(cdev);
 304
 305         return 0;
 306 }
 307
 308 static int acpi_fan_suspend(struct acpi_device *device, pm_message_t state)
 309 {
 310         if (!device)
 311                 return -EINVAL;
 312
 313         acpi_bus_set_power(device->handle, ACPI_STATE_D0);
 314
 315         return AE_OK;
 316 }
 317
 318 static int acpi_fan_resume(struct acpi_device *device)
 319 {
 320         int result = 0;
 321         int power_state = 0;
 322
 323         if (!device)
 324                 return -EINVAL;
 325
 326         result = acpi_bus_get_power(device->handle, &power_state);
 327         if (result) {
 328                 printk(KERN_ERR PREFIX
 329                                   "Error reading fan power state\n");
 330                 return result;
 331         }
 332
 333         device->flags.force_power_state = 1;
 334         acpi_bus_set_power(device->handle, power_state);
 335         device->flags.force_power_state = 0;
 336
 337         return result;
 338 }
 339
 340 static int __init acpi_fan_init(void)
 341 {
 342         int result = 0;
 343
 344
 345 #ifdef CONFIG_ACPI_PROCFS
 346         acpi_fan_dir = proc_mkdir(ACPI_FAN_CLASS, acpi_root_dir);
 347         if (!acpi_fan_dir)
 348                 return -ENODEV;
 349 #endif
 350
 351         result = acpi_bus_register_driver(&acpi_fan_driver);
 352         if (result < 0) {
 353                 remove_proc_entry(ACPI_FAN_CLASS, acpi_root_dir);
 354                 return -ENODEV;
 355         }
 356
 357         return 0;
 358 }
 359
 360 static void __exit acpi_fan_exit(void)
 361 {
 362
 363         acpi_bus_unregister_driver(&acpi_fan_driver);
 364
 365         remove_proc_entry(ACPI_FAN_CLASS, acpi_root_dir);
 366
 367         return;
 368 }
 369
 370 module_init(acpi_fan_init);
 371 module_exit(acpi_fan_exit);