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_COMPONENT              0x00200000
  38 #define ACPI_FAN_CLASS                  "fan"
  39 #define ACPI_FAN_FILE_STATE             "state"
  40
  41 #define _COMPONENT              ACPI_FAN_COMPONENT
  42 ACPI_MODULE_NAME("fan");
  43
  44 MODULE_AUTHOR("Paul Diefenbaugh");
  45 MODULE_DESCRIPTION("ACPI Fan Driver");
  46 MODULE_LICENSE("GPL");
  47
  48 static int acpi_fan_add(struct acpi_device *device);
  49 static int acpi_fan_remove(struct acpi_device *device, int type);
  50 static int acpi_fan_suspend(struct acpi_device *device, pm_message_t state);
  51 static int acpi_fan_resume(struct acpi_device *device);
  52
  53 static const struct acpi_device_id fan_device_ids[] = {
  54         {"PNP0C0B", 0},
  55         {"", 0},
  56 };
  57 MODULE_DEVICE_TABLE(acpi, fan_device_ids);
  58
  59 static struct acpi_driver acpi_fan_driver = {
  60         .name = "fan",
  61         .class = ACPI_FAN_CLASS,
  62         .ids = fan_device_ids,
  63         .ops = {
  64                 .add = acpi_fan_add,
  65                 .remove = acpi_fan_remove,
  66                 .suspend = acpi_fan_suspend,
  67                 .resume = acpi_fan_resume,
  68                 },
  69 };
  70
  71 /* thermal cooling device callbacks */
  72 static int fan_get_max_state(struct thermal_cooling_device *cdev, char *buf)
  73 {
  74         /* ACPI fan device only support two states: ON/OFF */
  75         return sprintf(buf, "1\n");
  76 }
  77
  78 static int fan_get_cur_state(struct thermal_cooling_device *cdev, char *buf)
  79 {
  80         struct acpi_device *device = cdev->devdata;
  81         int state;
  82         int result;
  83
  84         if (!device)
  85                 return -EINVAL;
  86
  87         result = acpi_bus_get_power(device->handle, &state);
  88         if (result)
  89                 return result;
  90
  91         return sprintf(buf, "%s\n", state == ACPI_STATE_D3 ? "0" :
  92                          (state == ACPI_STATE_D0 ? "1" : "unknown"));
  93 }
  94
  95 static int
  96 fan_set_cur_state(struct thermal_cooling_device *cdev, unsigned int state)
  97 {
  98         struct acpi_device *device = cdev->devdata;
  99         int result;
 100
 101         if (!device || (state != 0 && state != 1))
 102                 return -EINVAL;
 103
 104         result = acpi_bus_set_power(device->handle,
 105                                 state ? ACPI_STATE_D0 : ACPI_STATE_D3);
 106
 107         return result;
 108 }
 109
 110 static struct thermal_cooling_device_ops fan_cooling_ops = {
 111         .get_max_state = fan_get_max_state,
 112         .get_cur_state = fan_get_cur_state,
 113         .set_cur_state = fan_set_cur_state,
 114 };
 115
 116 /* --------------------------------------------------------------------------
 117                               FS Interface (/proc)
 118    -------------------------------------------------------------------------- */
 119 #ifdef CONFIG_ACPI_PROCFS
 120
 121 static struct proc_dir_entry *acpi_fan_dir;
 122
 123 static int acpi_fan_read_state(struct seq_file *seq, void *offset)
 124 {
 125         struct acpi_device *device = seq->private;
 126         int state = 0;
 127
 128
 129         if (device) {
 130                 if (acpi_bus_get_power(device->handle, &state))
 131                         seq_printf(seq, "status:                  ERROR\n");
 132                 else
 133                         seq_printf(seq, "status:                  %s\n",
 134                                    !state ? "on" : "off");
 135         }
 136         return 0;
 137 }
 138
 139 static int acpi_fan_state_open_fs(struct inode *inode, struct file *file)
 140 {
 141         return single_open(file, acpi_fan_read_state, PDE(inode)->data);
 142 }
 143
 144 static ssize_t
 145 acpi_fan_write_state(struct file *file, const char __user * buffer,
 146                      size_t count, loff_t * ppos)
 147 {
 148         int result = 0;
 149         struct seq_file *m = file->private_data;
 150         struct acpi_device *device = m->private;
 151         char state_string[3] = { '\0' };
 152
 153         if (count > sizeof(state_string) - 1)
 154                 return -EINVAL;
 155
 156         if (copy_from_user(state_string, buffer, count))
 157                 return -EFAULT;
 158
 159         state_string[count] = '\0';
 160         if ((state_string[0] < '0') || (state_string[0] > '3'))
 161                 return -EINVAL;
 162         if (state_string[1] == '\n')
 163                 state_string[1] = '\0';
 164         if (state_string[1] != '\0')
 165                 return -EINVAL;
 166
 167         result = acpi_bus_set_power(device->handle,
 168                                     simple_strtoul(state_string, NULL, 0));
 169         if (result)
 170                 return result;
 171
 172         return count;
 173 }
 174
 175 static const struct file_operations acpi_fan_state_ops = {
 176         .open = acpi_fan_state_open_fs,
 177         .read = seq_read,
 178         .write = acpi_fan_write_state,
 179         .llseek = seq_lseek,
 180         .release = single_release,
 181         .owner = THIS_MODULE,
 182 };
 183
 184 static int acpi_fan_add_fs(struct acpi_device *device)
 185 {
 186         struct proc_dir_entry *entry = NULL;
 187
 188
 189         if (!device)
 190                 return -EINVAL;
 191
 192         if (!acpi_device_dir(device)) {
 193                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 194                                                      acpi_fan_dir);
 195                 if (!acpi_device_dir(device))
 196                         return -ENODEV;
 197                 acpi_device_dir(device)->owner = THIS_MODULE;
 198         }
 199
 200         /* 'status' [R/W] */
 201         entry = proc_create_data(ACPI_FAN_FILE_STATE,
 202                                  S_IFREG | S_IRUGO | S_IWUSR,
 203                                  acpi_device_dir(device),
 204                                  &acpi_fan_state_ops,
 205                                  device);
 206         if (!entry)
 207                 return -ENODEV;
 208         return 0;
 209 }
 210
 211 static int acpi_fan_remove_fs(struct acpi_device *device)
 212 {
 213
 214         if (acpi_device_dir(device)) {
 215                 remove_proc_entry(ACPI_FAN_FILE_STATE, acpi_device_dir(device));
 216                 remove_proc_entry(acpi_device_bid(device), acpi_fan_dir);
 217                 acpi_device_dir(device) = NULL;
 218         }
 219
 220         return 0;
 221 }
 222 #else
 223 static int acpi_fan_add_fs(struct acpi_device *device)
 224 {
 225         return 0;
 226 }
 227
 228 static int acpi_fan_remove_fs(struct acpi_device *device)
 229 {
 230         return 0;
 231 }
 232 #endif
 233 /* --------------------------------------------------------------------------
 234                                  Driver Interface
 235    -------------------------------------------------------------------------- */
 236
 237 static int acpi_fan_add(struct acpi_device *device)
 238 {
 239         int result = 0;
 240         int state = 0;
 241         struct thermal_cooling_device *cdev;
 242
 243         if (!device)
 244                 return -EINVAL;
 245
 246         strcpy(acpi_device_name(device), "Fan");
 247         strcpy(acpi_device_class(device), ACPI_FAN_CLASS);
 248
 249         result = acpi_bus_get_power(device->handle, &state);
 250         if (result) {
 251                 printk(KERN_ERR PREFIX "Reading power state\n");
 252                 goto end;
 253         }
 254
 255         device->flags.force_power_state = 1;
 256         acpi_bus_set_power(device->handle, state);
 257         device->flags.force_power_state = 0;
 258
 259         cdev = thermal_cooling_device_register("Fan", device,
 260                                                 &fan_cooling_ops);
 261         if (IS_ERR(cdev)) {
 262                 result = PTR_ERR(cdev);
 263                 goto end;
 264         }
 265
 266         dev_info(&device->dev, "registered as cooling_device%d\n", cdev->id);
 267
 268         device->driver_data = cdev;
 269         result = sysfs_create_link(&device->dev.kobj,
 270                                    &cdev->device.kobj,
 271                                    "thermal_cooling");
 272         if (result)
 273                 dev_err(&device->dev, "Failed to create sysfs link "
 274                         "'thermal_cooling'\n");
 275
 276         result = sysfs_create_link(&cdev->device.kobj,
 277                                    &device->dev.kobj,
 278                                    "device");
 279         if (result)
 280                 dev_err(&device->dev, "Failed to create sysfs link "
 281                         "'device'\n");
 282
 283         result = acpi_fan_add_fs(device);
 284         if (result)
 285                 goto end;
 286
 287         printk(KERN_INFO PREFIX "%s [%s] (%s)\n",
 288                acpi_device_name(device), acpi_device_bid(device),
 289                !device->power.state ? "on" : "off");
 290
 291       end:
 292         return result;
 293 }
 294
 295 static int acpi_fan_remove(struct acpi_device *device, int type)
 296 {
 297         struct thermal_cooling_device *cdev = acpi_driver_data(device);
 298
 299         if (!device || !cdev)
 300                 return -EINVAL;
 301
 302         acpi_fan_remove_fs(device);
 303         sysfs_remove_link(&device->dev.kobj, "thermal_cooling");
 304         sysfs_remove_link(&cdev->device.kobj, "device");
 305         thermal_cooling_device_unregister(cdev);
 306
 307         return 0;
 308 }
 309
 310 static int acpi_fan_suspend(struct acpi_device *device, pm_message_t state)
 311 {
 312         if (!device)
 313                 return -EINVAL;
 314
 315         acpi_bus_set_power(device->handle, ACPI_STATE_D0);
 316
 317         return AE_OK;
 318 }
 319
 320 static int acpi_fan_resume(struct acpi_device *device)
 321 {
 322         int result = 0;
 323         int power_state = 0;
 324
 325         if (!device)
 326                 return -EINVAL;
 327
 328         result = acpi_bus_get_power(device->handle, &power_state);
 329         if (result) {
 330                 printk(KERN_ERR PREFIX
 331                                   "Error reading fan power state\n");
 332                 return result;
 333         }
 334
 335         device->flags.force_power_state = 1;
 336         acpi_bus_set_power(device->handle, power_state);
 337         device->flags.force_power_state = 0;
 338
 339         return result;
 340 }
 341
 342 static int __init acpi_fan_init(void)
 343 {
 344         int result = 0;
 345
 346
 347 #ifdef CONFIG_ACPI_PROCFS
 348         acpi_fan_dir = proc_mkdir(ACPI_FAN_CLASS, acpi_root_dir);
 349         if (!acpi_fan_dir)
 350                 return -ENODEV;
 351         acpi_fan_dir->owner = THIS_MODULE;
 352 #endif
 353
 354         result = acpi_bus_register_driver(&acpi_fan_driver);
 355         if (result < 0) {
 356                 remove_proc_entry(ACPI_FAN_CLASS, acpi_root_dir);
 357                 return -ENODEV;
 358         }
 359
 360         return 0;
 361 }
 362
 363 static void __exit acpi_fan_exit(void)
 364 {
 365
 366         acpi_bus_unregister_driver(&acpi_fan_driver);
 367
 368         remove_proc_entry(ACPI_FAN_CLASS, acpi_root_dir);
 369
 370         return;
 371 }
 372
 373 module_init(acpi_fan_init);
 374 module_exit(acpi_fan_exit);