drivers/acpi/ac.c

   1 /*
   2  *  acpi_ac.c - ACPI AC Adapter Driver ($Revision: 27 $)
   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 <acpi/acpi_bus.h>
  33 #include <acpi/acpi_drivers.h>
  34
  35 #define ACPI_AC_COMPONENT               0x00020000
  36 #define ACPI_AC_CLASS                   "ac_adapter"
  37 #define ACPI_AC_DEVICE_NAME             "AC Adapter"
  38 #define ACPI_AC_FILE_STATE              "state"
  39 #define ACPI_AC_NOTIFY_STATUS           0x80
  40 #define ACPI_AC_STATUS_OFFLINE          0x00
  41 #define ACPI_AC_STATUS_ONLINE           0x01
  42 #define ACPI_AC_STATUS_UNKNOWN          0xFF
  43
  44 #define _COMPONENT              ACPI_AC_COMPONENT
  45 ACPI_MODULE_NAME("ac");
  46
  47 MODULE_AUTHOR("Paul Diefenbaugh");
  48 MODULE_DESCRIPTION("ACPI AC Adapter Driver");
  49 MODULE_LICENSE("GPL");
  50
  51 extern struct proc_dir_entry *acpi_lock_ac_dir(void);
  52 extern void *acpi_unlock_ac_dir(struct proc_dir_entry *acpi_ac_dir);
  53
  54 static int acpi_ac_add(struct acpi_device *device);
  55 static int acpi_ac_remove(struct acpi_device *device, int type);
  56 static int acpi_ac_open_fs(struct inode *inode, struct file *file);
  57
  58 const static struct acpi_device_id ac_device_ids[] = {
  59         {"ACPI0003", 0},
  60         {"", 0},
  61 };
  62 MODULE_DEVICE_TABLE(acpi, ac_device_ids);
  63
  64 static struct acpi_driver acpi_ac_driver = {
  65         .name = "ac",
  66         .class = ACPI_AC_CLASS,
  67         .ids = ac_device_ids,
  68         .ops = {
  69                 .add = acpi_ac_add,
  70                 .remove = acpi_ac_remove,
  71                 },
  72 };
  73
  74 struct acpi_ac {
  75         struct acpi_device * device;
  76         unsigned long state;
  77 };
  78
  79 static const struct file_operations acpi_ac_fops = {
  80         .open = acpi_ac_open_fs,
  81         .read = seq_read,
  82         .llseek = seq_lseek,
  83         .release = single_release,
  84 };
  85
  86 /* --------------------------------------------------------------------------
  87                                AC Adapter Management
  88    -------------------------------------------------------------------------- */
  89
  90 static int acpi_ac_get_state(struct acpi_ac *ac)
  91 {
  92         acpi_status status = AE_OK;
  93
  94
  95         if (!ac)
  96                 return -EINVAL;
  97
  98         status = acpi_evaluate_integer(ac->device->handle, "_PSR", NULL, &ac->state);
  99         if (ACPI_FAILURE(status)) {
 100                 ACPI_EXCEPTION((AE_INFO, status, "Error reading AC Adapter state"));
 101                 ac->state = ACPI_AC_STATUS_UNKNOWN;
 102                 return -ENODEV;
 103         }
 104
 105         return 0;
 106 }
 107
 108 /* --------------------------------------------------------------------------
 109                               FS Interface (/proc)
 110    -------------------------------------------------------------------------- */
 111
 112 static struct proc_dir_entry *acpi_ac_dir;
 113
 114 static int acpi_ac_seq_show(struct seq_file *seq, void *offset)
 115 {
 116         struct acpi_ac *ac = seq->private;
 117
 118
 119         if (!ac)
 120                 return 0;
 121
 122         if (acpi_ac_get_state(ac)) {
 123                 seq_puts(seq, "ERROR: Unable to read AC Adapter state\n");
 124                 return 0;
 125         }
 126
 127         seq_puts(seq, "state:                   ");
 128         switch (ac->state) {
 129         case ACPI_AC_STATUS_OFFLINE:
 130                 seq_puts(seq, "off-line\n");
 131                 break;
 132         case ACPI_AC_STATUS_ONLINE:
 133                 seq_puts(seq, "on-line\n");
 134                 break;
 135         default:
 136                 seq_puts(seq, "unknown\n");
 137                 break;
 138         }
 139
 140         return 0;
 141 }
 142
 143 static int acpi_ac_open_fs(struct inode *inode, struct file *file)
 144 {
 145         return single_open(file, acpi_ac_seq_show, PDE(inode)->data);
 146 }
 147
 148 static int acpi_ac_add_fs(struct acpi_device *device)
 149 {
 150         struct proc_dir_entry *entry = NULL;
 151
 152
 153         if (!acpi_device_dir(device)) {
 154                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 155                                                      acpi_ac_dir);
 156                 if (!acpi_device_dir(device))
 157                         return -ENODEV;
 158                 acpi_device_dir(device)->owner = THIS_MODULE;
 159         }
 160
 161         /* 'state' [R] */
 162         entry = create_proc_entry(ACPI_AC_FILE_STATE,
 163                                   S_IRUGO, acpi_device_dir(device));
 164         if (!entry)
 165                 return -ENODEV;
 166         else {
 167                 entry->proc_fops = &acpi_ac_fops;
 168                 entry->data = acpi_driver_data(device);
 169                 entry->owner = THIS_MODULE;
 170         }
 171
 172         return 0;
 173 }
 174
 175 static int acpi_ac_remove_fs(struct acpi_device *device)
 176 {
 177
 178         if (acpi_device_dir(device)) {
 179                 remove_proc_entry(ACPI_AC_FILE_STATE, acpi_device_dir(device));
 180
 181                 remove_proc_entry(acpi_device_bid(device), acpi_ac_dir);
 182                 acpi_device_dir(device) = NULL;
 183         }
 184
 185         return 0;
 186 }
 187
 188 /* --------------------------------------------------------------------------
 189                                    Driver Model
 190    -------------------------------------------------------------------------- */
 191
 192 static void acpi_ac_notify(acpi_handle handle, u32 event, void *data)
 193 {
 194         struct acpi_ac *ac = data;
 195         struct acpi_device *device = NULL;
 196
 197
 198         if (!ac)
 199                 return;
 200
 201         device = ac->device;
 202         switch (event) {
 203         case ACPI_AC_NOTIFY_STATUS:
 204         case ACPI_NOTIFY_BUS_CHECK:
 205         case ACPI_NOTIFY_DEVICE_CHECK:
 206                 acpi_ac_get_state(ac);
 207                 acpi_bus_generate_event(device, event, (u32) ac->state);
 208                 break;
 209         default:
 210                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 211                                   "Unsupported event [0x%x]\n", event));
 212                 break;
 213         }
 214
 215         return;
 216 }
 217
 218 static int acpi_ac_add(struct acpi_device *device)
 219 {
 220         int result = 0;
 221         acpi_status status = AE_OK;
 222         struct acpi_ac *ac = NULL;
 223
 224
 225         if (!device)
 226                 return -EINVAL;
 227
 228         ac = kzalloc(sizeof(struct acpi_ac), GFP_KERNEL);
 229         if (!ac)
 230                 return -ENOMEM;
 231
 232         ac->device = device;
 233         strcpy(acpi_device_name(device), ACPI_AC_DEVICE_NAME);
 234         strcpy(acpi_device_class(device), ACPI_AC_CLASS);
 235         acpi_driver_data(device) = ac;
 236
 237         result = acpi_ac_get_state(ac);
 238         if (result)
 239                 goto end;
 240
 241         result = acpi_ac_add_fs(device);
 242         if (result)
 243                 goto end;
 244
 245         status = acpi_install_notify_handler(device->handle,
 246                                              ACPI_ALL_NOTIFY, acpi_ac_notify,
 247                                              ac);
 248         if (ACPI_FAILURE(status)) {
 249                 result = -ENODEV;
 250                 goto end;
 251         }
 252
 253         printk(KERN_INFO PREFIX "%s [%s] (%s)\n",
 254                acpi_device_name(device), acpi_device_bid(device),
 255                ac->state ? "on-line" : "off-line");
 256
 257       end:
 258         if (result) {
 259                 acpi_ac_remove_fs(device);
 260                 kfree(ac);
 261         }
 262
 263         return result;
 264 }
 265
 266 static int acpi_ac_remove(struct acpi_device *device, int type)
 267 {
 268         acpi_status status = AE_OK;
 269         struct acpi_ac *ac = NULL;
 270
 271
 272         if (!device || !acpi_driver_data(device))
 273                 return -EINVAL;
 274
 275         ac = acpi_driver_data(device);
 276
 277         status = acpi_remove_notify_handler(device->handle,
 278                                             ACPI_ALL_NOTIFY, acpi_ac_notify);
 279
 280         acpi_ac_remove_fs(device);
 281
 282         kfree(ac);
 283
 284         return 0;
 285 }
 286
 287 static int __init acpi_ac_init(void)
 288 {
 289         int result;
 290
 291         if (acpi_disabled)
 292                 return -ENODEV;
 293
 294         acpi_ac_dir = acpi_lock_ac_dir();
 295         if (!acpi_ac_dir)
 296                 return -ENODEV;
 297
 298         result = acpi_bus_register_driver(&acpi_ac_driver);
 299         if (result < 0) {
 300                 acpi_unlock_ac_dir(acpi_ac_dir);
 301                 return -ENODEV;
 302         }
 303
 304         return 0;
 305 }
 306
 307 static void __exit acpi_ac_exit(void)
 308 {
 309
 310         acpi_bus_unregister_driver(&acpi_ac_driver);
 311
 312         acpi_unlock_ac_dir(acpi_ac_dir);
 313
 314         return;
 315 }
 316
 317 module_init(acpi_ac_init);
 318 module_exit(acpi_ac_exit);