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 PREFIX "ACPI: "
  38
  39 #define ACPI_FAN_CLASS                  "fan"
  40 #define ACPI_FAN_FILE_STATE             "state"
  41
  42 #define _COMPONENT              ACPI_FAN_COMPONENT
  43 ACPI_MODULE_NAME("fan");
  44
  45 MODULE_AUTHOR("Paul Diefenbaugh");
  46 MODULE_DESCRIPTION("ACPI Fan Driver");
  47 MODULE_LICENSE("GPL");
  48
  49 static int acpi_fan_add(struct acpi_device *device);
  50 static int acpi_fan_remove(struct acpi_device *device, int type);
  51 static int acpi_fan_suspend(struct acpi_device *device, pm_message_t state);
  52 static int acpi_fan_resume(struct acpi_device *device);
  53
  54 static const struct acpi_device_id fan_device_ids[] = {
  55         {"PNP0C0B", 0},
  56         {"", 0},
  57 };
  58 MODULE_DEVICE_TABLE(acpi, fan_device_ids);
  59
  60 static struct acpi_driver acpi_fan_driver = {
  61         .name = "fan",
  62         .class = ACPI_FAN_CLASS,
  63         .ids = fan_device_ids,
  64         .ops = {
  65                 .add = acpi_fan_add,
  66                 .remove = acpi_fan_remove,
  67                 .suspend = acpi_fan_suspend,
  68                 .resume = acpi_fan_resume,
  69                 },
  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;
  87
  88         if (!device)
  89                 return -EINVAL;
  90
  91         result = acpi_bus_get_power(device->handle, &acpi_state);
  92         if (result)
  93                 return result;
  94
  95         *state = (acpi_state == ACPI_STATE_D3 ? 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);
 111
 112         return result;
 113 }
 114
 115 static 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                               FS Interface (/proc)
 123    -------------------------------------------------------------------------- */
 124 #ifdef CONFIG_ACPI_PROCFS
 125
 126 static struct proc_dir_entry *acpi_fan_dir;
 127
 128 static int acpi_fan_read_state(struct seq_file *seq, void *offset)
 129 {
 130         struct acpi_device *device = seq->private;
 131         int state = 0;
 132
 133
 134         if (device) {
 135                 if (acpi_bus_get_power(device->handle, &state))
 136                         seq_printf(seq, "status:                  ERROR\n");
 137                 else
 138                         seq_printf(seq, "status:                  %s\n",
 139                                    !state ? "on" : "off");
 140         }
 141         return 0;
 142 }
 143
 144 static int acpi_fan_state_open_fs(struct inode *inode, struct file *file)
 145 {
 146         return single_open(file, acpi_fan_read_state, PDE(inode)->data);
 147 }
 148
 149 static ssize_t
 150 acpi_fan_write_state(struct file *file, const char __user * buffer,
 151                      size_t count, loff_t * ppos)
 152 {
 153         int result = 0;
 154         struct seq_file *m = file->private_data;
 155         struct acpi_device *device = m->private;
 156         char state_string[3] = { '\0' };
 157
 158         if (count > sizeof(state_string) - 1)
 159                 return -EINVAL;
 160
 161         if (copy_from_user(state_string, buffer, count))
 162                 return -EFAULT;
 163
 164         state_string[count] = '\0';
 165         if ((state_string[0] < '0') || (state_string[0] > '3'))
 166                 return -EINVAL;
 167         if (state_string[1] == '\n')
 168                 state_string[1] = '\0';
 169         if (state_string[1] != '\0')
 170                 return -EINVAL;
 171
 172         result = acpi_bus_set_power(device->handle,
 173                                     simple_strtoul(state_string, NULL, 0));
 174         if (result)
 175                 return result;
 176
 177         return count;
 178 }
 179
 180 static const struct file_operations acpi_fan_state_ops = {
 181         .open = acpi_fan_state_open_fs,
 182         .read = seq_read,
 183         .write = acpi_fan_write_state,
 184         .llseek = seq_lseek,
 185         .release = single_release,
 186         .owner = THIS_MODULE,
 187 };
 188
 189 static int acpi_fan_add_fs(struct acpi_device *device)
 190 {
 191         struct proc_dir_entry *entry = NULL;
 192
 193
 194         if (!device)
 195                 return -EINVAL;
 196
 197         if (!acpi_device_dir(device)) {
 198                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 199                                                      acpi_fan_dir);
 200                 if (!acpi_device_dir(device))
 201                         return -ENODEV;
 202         }
 203
 204         /* 'status' [R/W] */
 205         entry = proc_create_data(ACPI_FAN_FILE_STATE,
 206                                  S_IFREG | S_IRUGO | S_IWUSR,
 207                                  acpi_device_dir(device),
 208                                  &acpi_fan_state_ops,
 209                                  device);
 210         if (!entry)
 211                 return -ENODEV;
 212         return 0;
 213 }
 214
 215 static int acpi_fan_remove_fs(struct acpi_device *device)
 216 {
 217
 218         if (acpi_device_dir(device)) {
 219                 remove_proc_entry(ACPI_FAN_FILE_STATE, acpi_device_dir(device));
 220                 remove_proc_entry(acpi_device_bid(device), acpi_fan_dir);
 221                 acpi_device_dir(device) = NULL;
 222         }
 223
 224         return 0;
 225 }
 226 #else
 227 static int acpi_fan_add_fs(struct acpi_device *device)
 228 {
 229         return 0;
 230 }
 231
 232 static int acpi_fan_remove_fs(struct acpi_device *device)
 233 {
 234         return 0;
 235 }
 236 #endif
 237 /* --------------------------------------------------------------------------
 238                                  Driver Interface
 239    -------------------------------------------------------------------------- */
 240
 241 static int acpi_fan_add(struct acpi_device *device)
 242 {
 243         int result = 0;
 244         int state = 0;
 245         struct thermal_cooling_device *cdev;
 246
 247         if (!device)
 248                 return -EINVAL;
 249
 250         strcpy(acpi_device_name(device), "Fan");
 251         strcpy(acpi_device_class(device), ACPI_FAN_CLASS);
 252
 253         result = acpi_bus_get_power(device->handle, &state);
 254         if (result) {
 255                 printk(KERN_ERR PREFIX "Reading power state\n");
 256                 goto end;
 257         }
 258
 259         device->flags.force_power_state = 1;
 260         acpi_bus_set_power(device->handle, state);
 261         device->flags.force_power_state = 0;
 262
 263         cdev = thermal_cooling_device_register("Fan", device,
 264                                                 &fan_cooling_ops);
 265         if (IS_ERR(cdev)) {
 266                 result = PTR_ERR(cdev);
 267                 goto end;
 268         }
 269
 270         dev_dbg(&device->dev, "registered as cooling_device%d\n", cdev->id);
 271
 272         device->driver_data = cdev;
 273         result = sysfs_create_link(&device->dev.kobj,
 274                                    &cdev->device.kobj,
 275                                    "thermal_cooling");
 276         if (result)
 277                 dev_err(&device->dev, "Failed to create sysfs link "
 278                         "'thermal_cooling'\n");
 279
 280         result = sysfs_create_link(&cdev->device.kobj,
 281                                    &device->dev.kobj,
 282                                    "device");
 283         if (result)
 284                 dev_err(&device->dev, "Failed to create sysfs link "
 285                         "'device'\n");
 286
 287         result = acpi_fan_add_fs(device);
 288         if (result)
 289                 goto end;
 290
 291         printk(KERN_INFO PREFIX "%s [%s] (%s)\n",
 292                acpi_device_name(device), acpi_device_bid(device),
 293                !device->power.state ? "on" : "off");
 294
 295       end:
 296         return result;
 297 }
 298
 299 static int acpi_fan_remove(struct acpi_device *device, int type)
 300 {
 301         struct thermal_cooling_device *cdev = acpi_driver_data(device);
 302
 303         if (!device || !cdev)
 304                 return -EINVAL;
 305
 306         acpi_fan_remove_fs(device);
 307         sysfs_remove_link(&device->dev.kobj, "thermal_cooling");
 308         sysfs_remove_link(&cdev->device.kobj, "device");
 309         thermal_cooling_device_unregister(cdev);
 310
 311         return 0;
 312 }
 313
 314 static int acpi_fan_suspend(struct acpi_device *device, pm_message_t state)
 315 {
 316         if (!device)
 317                 return -EINVAL;
 318
 319         acpi_bus_set_power(device->handle, ACPI_STATE_D0);
 320
 321         return AE_OK;
 322 }
 323
 324 static int acpi_fan_resume(struct acpi_device *device)
 325 {
 326         int result = 0;
 327         int power_state = 0;
 328
 329         if (!device)
 330                 return -EINVAL;
 331
 332         result = acpi_bus_get_power(device->handle, &power_state);
 333         if (result) {
 334                 printk(KERN_ERR PREFIX
 335                                   "Error reading fan power state\n");
 336                 return result;
 337         }
 338
 339         device->flags.force_power_state = 1;
 340         acpi_bus_set_power(device->handle, power_state);
 341         device->flags.force_power_state = 0;
 342
 343         return result;
 344 }
 345
 346 static int __init acpi_fan_init(void)
 347 {
 348         int result = 0;
 349
 350
 351 #ifdef CONFIG_ACPI_PROCFS
 352         acpi_fan_dir = proc_mkdir(ACPI_FAN_CLASS, acpi_root_dir);
 353         if (!acpi_fan_dir)
 354                 return -ENODEV;
 355 #endif
 356
 357         result = acpi_bus_register_driver(&acpi_fan_driver);
 358         if (result < 0) {
 359                 remove_proc_entry(ACPI_FAN_CLASS, acpi_root_dir);
 360                 return -ENODEV;
 361         }
 362
 363         return 0;
 364 }
 365
 366 static void __exit acpi_fan_exit(void)
 367 {
 368
 369         acpi_bus_unregister_driver(&acpi_fan_driver);
 370
 371         remove_proc_entry(ACPI_FAN_CLASS, acpi_root_dir);
 372
 373         return;
 374 }
 375
 376 module_init(acpi_fan_init);
 377 module_exit(acpi_fan_exit);