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
  51 static const struct acpi_device_id fan_device_ids[] = {
  52         {"PNP0C0B", 0},
  53         {"", 0},
  54 };
  55 MODULE_DEVICE_TABLE(acpi, fan_device_ids);
  56
  57 static struct acpi_driver acpi_fan_driver = {
  58         .name = "fan",
  59         .class = ACPI_FAN_CLASS,
  60         .ids = fan_device_ids,
  61         .ops = {
  62                 .add = acpi_fan_add,
  63                 .remove = acpi_fan_remove,
  64                 },
  65 };
  66
  67 /* --------------------------------------------------------------------------
  68                               FS Interface (/proc)
  69    -------------------------------------------------------------------------- */
  70
  71 static struct proc_dir_entry *acpi_fan_dir;
  72
  73 static int acpi_fan_read_state(struct seq_file *seq, void *offset)
  74 {
  75         struct acpi_device *device = seq->private;
  76         int state = 0;
  77
  78
  79         if (device) {
  80                 if (acpi_bus_get_power(device->handle, &state))
  81                         seq_printf(seq, "status:                  ERROR\n");
  82                 else
  83                         seq_printf(seq, "status:                  %s\n",
  84                                    !state ? "on" : "off");
  85         }
  86         return 0;
  87 }
  88
  89 static int acpi_fan_state_open_fs(struct inode *inode, struct file *file)
  90 {
  91         return single_open(file, acpi_fan_read_state, PDE(inode)->data);
  92 }
  93
  94 static ssize_t
  95 acpi_fan_write_state(struct file *file, const char __user * buffer,
  96                      size_t count, loff_t * ppos)
  97 {
  98         int result = 0;
  99         struct seq_file *m = file->private_data;
 100         struct acpi_device *device = m->private;
 101         char state_string[12] = { '\0' };
 102
 103         if (count > sizeof(state_string) - 1)
 104                 return -EINVAL;
 105
 106         if (copy_from_user(state_string, buffer, count))
 107                 return -EFAULT;
 108
 109         state_string[count] = '\0';
 110
 111         result = acpi_bus_set_power(device->handle,
 112                                     simple_strtoul(state_string, NULL, 0));
 113         if (result)
 114                 return result;
 115
 116         return count;
 117 }
 118
 119 static const struct file_operations acpi_fan_state_ops = {
 120         .open = acpi_fan_state_open_fs,
 121         .read = seq_read,
 122         .write = acpi_fan_write_state,
 123         .llseek = seq_lseek,
 124         .release = single_release,
 125         .owner = THIS_MODULE,
 126 };
 127
 128 static int acpi_fan_add_fs(struct acpi_device *device)
 129 {
 130         struct proc_dir_entry *entry = NULL;
 131
 132
 133         if (!device)
 134                 return -EINVAL;
 135
 136         if (!acpi_device_dir(device)) {
 137                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 138                                                      acpi_fan_dir);
 139                 if (!acpi_device_dir(device))
 140                         return -ENODEV;
 141                 acpi_device_dir(device)->owner = THIS_MODULE;
 142         }
 143
 144         /* 'status' [R/W] */
 145         entry = create_proc_entry(ACPI_FAN_FILE_STATE,
 146                                   S_IFREG | S_IRUGO | S_IWUSR,
 147                                   acpi_device_dir(device));
 148         if (!entry)
 149                 return -ENODEV;
 150         else {
 151                 entry->proc_fops = &acpi_fan_state_ops;
 152                 entry->data = device;
 153                 entry->owner = THIS_MODULE;
 154         }
 155
 156         return 0;
 157 }
 158
 159 static int acpi_fan_remove_fs(struct acpi_device *device)
 160 {
 161
 162         if (acpi_device_dir(device)) {
 163                 remove_proc_entry(ACPI_FAN_FILE_STATE, acpi_device_dir(device));
 164                 remove_proc_entry(acpi_device_bid(device), acpi_fan_dir);
 165                 acpi_device_dir(device) = NULL;
 166         }
 167
 168         return 0;
 169 }
 170
 171 /* --------------------------------------------------------------------------
 172                                  Driver Interface
 173    -------------------------------------------------------------------------- */
 174
 175 static int acpi_fan_add(struct acpi_device *device)
 176 {
 177         int result = 0;
 178         struct acpi_fan *fan = NULL;
 179         int state = 0;
 180
 181
 182         if (!device)
 183                 return -EINVAL;
 184
 185         strcpy(acpi_device_name(device), "Fan");
 186         strcpy(acpi_device_class(device), ACPI_FAN_CLASS);
 187
 188         result = acpi_bus_get_power(device->handle, &state);
 189         if (result) {
 190                 printk(KERN_ERR PREFIX "Reading power state\n");
 191                 goto end;
 192         }
 193
 194         result = acpi_fan_add_fs(device);
 195         if (result)
 196                 goto end;
 197
 198         printk(KERN_INFO PREFIX "%s [%s] (%s)\n",
 199                acpi_device_name(device), acpi_device_bid(device),
 200                !device->power.state ? "on" : "off");
 201
 202       end:
 203         if (result)
 204                 kfree(fan);
 205
 206         return result;
 207 }
 208
 209 static int acpi_fan_remove(struct acpi_device *device, int type)
 210 {
 211         if (!device || !acpi_driver_data(device))
 212                 return -EINVAL;
 213
 214         acpi_fan_remove_fs(device);
 215
 216         return 0;
 217 }
 218
 219 static int __init acpi_fan_init(void)
 220 {
 221         int result = 0;
 222
 223
 224         acpi_fan_dir = proc_mkdir(ACPI_FAN_CLASS, acpi_root_dir);
 225         if (!acpi_fan_dir)
 226                 return -ENODEV;
 227         acpi_fan_dir->owner = THIS_MODULE;
 228
 229         result = acpi_bus_register_driver(&acpi_fan_driver);
 230         if (result < 0) {
 231                 remove_proc_entry(ACPI_FAN_CLASS, acpi_root_dir);
 232                 return -ENODEV;
 233         }
 234
 235         return 0;
 236 }
 237
 238 static void __exit acpi_fan_exit(void)
 239 {
 240
 241         acpi_bus_unregister_driver(&acpi_fan_driver);
 242
 243         remove_proc_entry(ACPI_FAN_CLASS, acpi_root_dir);
 244
 245         return;
 246 }
 247
 248 module_init(acpi_fan_init);
 249 module_exit(acpi_fan_exit);