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_DRIVER_NAME            "ACPI Fan Driver"
  40 #define ACPI_FAN_FILE_STATE             "state"
  41
  42 #define _COMPONENT              ACPI_FAN_COMPONENT
  43 ACPI_MODULE_NAME("acpi_fan")
  44
  45     MODULE_AUTHOR("Paul Diefenbaugh");
  46 MODULE_DESCRIPTION(ACPI_FAN_DRIVER_NAME);
  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 struct acpi_driver acpi_fan_driver = {
  55         .name = ACPI_FAN_DRIVER_NAME,
  56         .class = ACPI_FAN_CLASS,
  57         .ids = "PNP0C0B",
  58         .ops = {
  59                 .add = acpi_fan_add,
  60                 .remove = acpi_fan_remove,
  61                 .suspend = acpi_fan_suspend,
  62                 .resume = acpi_fan_resume,
  63                 },
  64 };
  65
  66 struct acpi_fan {
  67         struct acpi_device * device;
  68 };
  69
  70 /* --------------------------------------------------------------------------
  71                               FS Interface (/proc)
  72    -------------------------------------------------------------------------- */
  73
  74 static struct proc_dir_entry *acpi_fan_dir;
  75
  76 static int acpi_fan_read_state(struct seq_file *seq, void *offset)
  77 {
  78         struct acpi_fan *fan = seq->private;
  79         int state = 0;
  80
  81
  82         if (fan) {
  83                 if (acpi_bus_get_power(fan->device->handle, &state))
  84                         seq_printf(seq, "status:                  ERROR\n");
  85                 else
  86                         seq_printf(seq, "status:                  %s\n",
  87                                    !state ? "on" : "off");
  88         }
  89         return 0;
  90 }
  91
  92 static int acpi_fan_state_open_fs(struct inode *inode, struct file *file)
  93 {
  94         return single_open(file, acpi_fan_read_state, PDE(inode)->data);
  95 }
  96
  97 static ssize_t
  98 acpi_fan_write_state(struct file *file, const char __user * buffer,
  99                      size_t count, loff_t * ppos)
 100 {
 101         int result = 0;
 102         struct seq_file *m = file->private_data;
 103         struct acpi_fan *fan = m->private;
 104         char state_string[12] = { '\0' };
 105
 106
 107         if (!fan || (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(fan->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 = acpi_driver_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         fan = kzalloc(sizeof(struct acpi_fan), GFP_KERNEL);
 190         if (!fan)
 191                 return -ENOMEM;
 192
 193         fan->device = device;
 194         strcpy(acpi_device_name(device), "Fan");
 195         strcpy(acpi_device_class(device), ACPI_FAN_CLASS);
 196         acpi_driver_data(device) = fan;
 197
 198         result = acpi_bus_get_power(device->handle, &state);
 199         if (result) {
 200                 printk(KERN_ERR PREFIX "Reading power state\n");
 201                 goto end;
 202         }
 203
 204         device->flags.force_power_state = 1;
 205         acpi_bus_set_power(device->handle, state);
 206         device->flags.force_power_state = 0;
 207
 208         result = acpi_fan_add_fs(device);
 209         if (result)
 210                 goto end;
 211
 212         printk(KERN_INFO PREFIX "%s [%s] (%s)\n",
 213                acpi_device_name(device), acpi_device_bid(device),
 214                !device->power.state ? "on" : "off");
 215
 216       end:
 217         if (result)
 218                 kfree(fan);
 219
 220         return result;
 221 }
 222
 223 static int acpi_fan_remove(struct acpi_device *device, int type)
 224 {
 225         struct acpi_fan *fan = NULL;
 226
 227
 228         if (!device || !acpi_driver_data(device))
 229                 return -EINVAL;
 230
 231         fan = acpi_driver_data(device);
 232
 233         acpi_fan_remove_fs(device);
 234
 235         kfree(fan);
 236
 237         return 0;
 238 }
 239
 240 static int acpi_fan_suspend(struct acpi_device *device, pm_message_t state)
 241 {
 242         if (!device)
 243                 return -EINVAL;
 244
 245         acpi_bus_set_power(device->handle, ACPI_STATE_D0);
 246
 247         return AE_OK;
 248 }
 249
 250 static int acpi_fan_resume(struct acpi_device *device)
 251 {
 252         int result = 0;
 253         int power_state = 0;
 254
 255         if (!device)
 256                 return -EINVAL;
 257
 258         result = acpi_bus_get_power(device->handle, &power_state);
 259         if (result) {
 260                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
 261                                   "Error reading fan power state\n"));
 262                 return result;
 263         }
 264
 265         device->flags.force_power_state = 1;
 266         acpi_bus_set_power(device->handle, power_state);
 267         device->flags.force_power_state = 0;
 268
 269         return result;
 270 }
 271
 272 static int __init acpi_fan_init(void)
 273 {
 274         int result = 0;
 275
 276
 277         acpi_fan_dir = proc_mkdir(ACPI_FAN_CLASS, acpi_root_dir);
 278         if (!acpi_fan_dir)
 279                 return -ENODEV;
 280         acpi_fan_dir->owner = THIS_MODULE;
 281
 282         result = acpi_bus_register_driver(&acpi_fan_driver);
 283         if (result < 0) {
 284                 remove_proc_entry(ACPI_FAN_CLASS, acpi_root_dir);
 285                 return -ENODEV;
 286         }
 287
 288         return 0;
 289 }
 290
 291 static void __exit acpi_fan_exit(void)
 292 {
 293
 294         acpi_bus_unregister_driver(&acpi_fan_driver);
 295
 296         remove_proc_entry(ACPI_FAN_CLASS, acpi_root_dir);
 297
 298         return;
 299 }
 300
 301 module_init(acpi_fan_init);
 302 module_exit(acpi_fan_exit);