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
  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 /* --------------------------------------------------------------------------
  72                               FS Interface (/proc)
  73    -------------------------------------------------------------------------- */
  74
  75 static struct proc_dir_entry *acpi_fan_dir;
  76
  77 static int acpi_fan_read_state(struct seq_file *seq, void *offset)
  78 {
  79         struct acpi_device *device = seq->private;
  80         int state = 0;
  81
  82
  83         if (device) {
  84                 if (acpi_bus_get_power(device->handle, &state))
  85                         seq_printf(seq, "status:                  ERROR\n");
  86                 else
  87                         seq_printf(seq, "status:                  %s\n",
  88                                    !state ? "on" : "off");
  89         }
  90         return 0;
  91 }
  92
  93 static int acpi_fan_state_open_fs(struct inode *inode, struct file *file)
  94 {
  95         return single_open(file, acpi_fan_read_state, PDE(inode)->data);
  96 }
  97
  98 static ssize_t
  99 acpi_fan_write_state(struct file *file, const char __user * buffer,
 100                      size_t count, loff_t * ppos)
 101 {
 102         int result = 0;
 103         struct seq_file *m = file->private_data;
 104         struct acpi_device *device = m->private;
 105         char state_string[12] = { '\0' };
 106
 107         if (count > sizeof(state_string) - 1)
 108                 return -EINVAL;
 109
 110         if (copy_from_user(state_string, buffer, count))
 111                 return -EFAULT;
 112
 113         state_string[count] = '\0';
 114
 115         result = acpi_bus_set_power(device->handle,
 116                                     simple_strtoul(state_string, NULL, 0));
 117         if (result)
 118                 return result;
 119
 120         return count;
 121 }
 122
 123 static const struct file_operations acpi_fan_state_ops = {
 124         .open = acpi_fan_state_open_fs,
 125         .read = seq_read,
 126         .write = acpi_fan_write_state,
 127         .llseek = seq_lseek,
 128         .release = single_release,
 129         .owner = THIS_MODULE,
 130 };
 131
 132 static int acpi_fan_add_fs(struct acpi_device *device)
 133 {
 134         struct proc_dir_entry *entry = NULL;
 135
 136
 137         if (!device)
 138                 return -EINVAL;
 139
 140         if (!acpi_device_dir(device)) {
 141                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 142                                                      acpi_fan_dir);
 143                 if (!acpi_device_dir(device))
 144                         return -ENODEV;
 145                 acpi_device_dir(device)->owner = THIS_MODULE;
 146         }
 147
 148         /* 'status' [R/W] */
 149         entry = create_proc_entry(ACPI_FAN_FILE_STATE,
 150                                   S_IFREG | S_IRUGO | S_IWUSR,
 151                                   acpi_device_dir(device));
 152         if (!entry)
 153                 return -ENODEV;
 154         else {
 155                 entry->proc_fops = &acpi_fan_state_ops;
 156                 entry->data = device;
 157                 entry->owner = THIS_MODULE;
 158         }
 159
 160         return 0;
 161 }
 162
 163 static int acpi_fan_remove_fs(struct acpi_device *device)
 164 {
 165
 166         if (acpi_device_dir(device)) {
 167                 remove_proc_entry(ACPI_FAN_FILE_STATE, acpi_device_dir(device));
 168                 remove_proc_entry(acpi_device_bid(device), acpi_fan_dir);
 169                 acpi_device_dir(device) = NULL;
 170         }
 171
 172         return 0;
 173 }
 174
 175 /* --------------------------------------------------------------------------
 176                                  Driver Interface
 177    -------------------------------------------------------------------------- */
 178
 179 static int acpi_fan_add(struct acpi_device *device)
 180 {
 181         int result = 0;
 182         struct acpi_fan *fan = NULL;
 183         int state = 0;
 184
 185
 186         if (!device)
 187                 return -EINVAL;
 188
 189         strcpy(acpi_device_name(device), "Fan");
 190         strcpy(acpi_device_class(device), ACPI_FAN_CLASS);
 191
 192         result = acpi_bus_get_power(device->handle, &state);
 193         if (result) {
 194                 printk(KERN_ERR PREFIX "Reading power state\n");
 195                 goto end;
 196         }
 197
 198         device->flags.force_power_state = 1;
 199         acpi_bus_set_power(device->handle, state);
 200         device->flags.force_power_state = 0;
 201
 202         result = acpi_fan_add_fs(device);
 203         if (result)
 204                 goto end;
 205
 206         printk(KERN_INFO PREFIX "%s [%s] (%s)\n",
 207                acpi_device_name(device), acpi_device_bid(device),
 208                !device->power.state ? "on" : "off");
 209
 210       end:
 211         if (result)
 212                 kfree(fan);
 213
 214         return result;
 215 }
 216
 217 static int acpi_fan_remove(struct acpi_device *device, int type)
 218 {
 219         if (!device || !acpi_driver_data(device))
 220                 return -EINVAL;
 221
 222         acpi_fan_remove_fs(device);
 223
 224         return 0;
 225 }
 226
 227 static int acpi_fan_suspend(struct acpi_device *device, pm_message_t state)
 228 {
 229         if (!device)
 230                 return -EINVAL;
 231
 232         acpi_bus_set_power(device->handle, ACPI_STATE_D0);
 233
 234         return AE_OK;
 235 }
 236
 237 static int acpi_fan_resume(struct acpi_device *device)
 238 {
 239         int result = 0;
 240         int power_state = 0;
 241
 242         if (!device)
 243                 return -EINVAL;
 244
 245         result = acpi_bus_get_power(device->handle, &power_state);
 246         if (result) {
 247                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
 248                                   "Error reading fan power state\n"));
 249                 return result;
 250         }
 251
 252         device->flags.force_power_state = 1;
 253         acpi_bus_set_power(device->handle, power_state);
 254         device->flags.force_power_state = 0;
 255
 256         return result;
 257 }
 258
 259 static int __init acpi_fan_init(void)
 260 {
 261         int result = 0;
 262
 263
 264         acpi_fan_dir = proc_mkdir(ACPI_FAN_CLASS, acpi_root_dir);
 265         if (!acpi_fan_dir)
 266                 return -ENODEV;
 267         acpi_fan_dir->owner = THIS_MODULE;
 268
 269         result = acpi_bus_register_driver(&acpi_fan_driver);
 270         if (result < 0) {
 271                 remove_proc_entry(ACPI_FAN_CLASS, acpi_root_dir);
 272                 return -ENODEV;
 273         }
 274
 275         return 0;
 276 }
 277
 278 static void __exit acpi_fan_exit(void)
 279 {
 280
 281         acpi_bus_unregister_driver(&acpi_fan_driver);
 282
 283         remove_proc_entry(ACPI_FAN_CLASS, acpi_root_dir);
 284
 285         return;
 286 }
 287
 288 module_init(acpi_fan_init);
 289 module_exit(acpi_fan_exit);