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_HID                     "ACPI0003"
  38 #define ACPI_AC_DRIVER_NAME             "ACPI AC Adapter Driver"
  39 #define ACPI_AC_DEVICE_NAME             "AC Adapter"
  40 #define ACPI_AC_FILE_STATE              "state"
  41 #define ACPI_AC_NOTIFY_STATUS           0x80
  42 #define ACPI_AC_STATUS_OFFLINE          0x00
  43 #define ACPI_AC_STATUS_ONLINE           0x01
  44 #define ACPI_AC_STATUS_UNKNOWN          0xFF
  45
  46 #define _COMPONENT              ACPI_AC_COMPONENT
  47 ACPI_MODULE_NAME("acpi_ac")
  48
  49     MODULE_AUTHOR("Paul Diefenbaugh");
  50 MODULE_DESCRIPTION(ACPI_AC_DRIVER_NAME);
  51 MODULE_LICENSE("GPL");
  52
  53 static int acpi_ac_add(struct acpi_device *device);
  54 static int acpi_ac_remove(struct acpi_device *device, int type);
  55 static int acpi_ac_open_fs(struct inode *inode, struct file *file);
  56
  57 static struct acpi_driver acpi_ac_driver = {
  58         .name = ACPI_AC_DRIVER_NAME,
  59         .class = ACPI_AC_CLASS,
  60         .ids = ACPI_AC_HID,
  61         .ops = {
  62                 .add = acpi_ac_add,
  63                 .remove = acpi_ac_remove,
  64                 },
  65 };
  66
  67 struct acpi_ac {
  68         acpi_handle handle;
  69         unsigned long state;
  70 };
  71
  72 static struct file_operations acpi_ac_fops = {
  73         .open = acpi_ac_open_fs,
  74         .read = seq_read,
  75         .llseek = seq_lseek,
  76         .release = single_release,
  77 };
  78
  79 /* --------------------------------------------------------------------------
  80                                AC Adapter Management
  81    -------------------------------------------------------------------------- */
  82
  83 static int acpi_ac_get_state(struct acpi_ac *ac)
  84 {
  85         acpi_status status = AE_OK;
  86
  87         ACPI_FUNCTION_TRACE("acpi_ac_get_state");
  88
  89         if (!ac)
  90                 return_VALUE(-EINVAL);
  91
  92         status = acpi_evaluate_integer(ac->handle, "_PSR", NULL, &ac->state);
  93         if (ACPI_FAILURE(status)) {
  94                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
  95                                   "Error reading AC Adapter state\n"));
  96                 ac->state = ACPI_AC_STATUS_UNKNOWN;
  97                 return_VALUE(-ENODEV);
  98         }
  99
 100         return_VALUE(0);
 101 }
 102
 103 /* --------------------------------------------------------------------------
 104                               FS Interface (/proc)
 105    -------------------------------------------------------------------------- */
 106
 107 static struct proc_dir_entry *acpi_ac_dir;
 108
 109 static int acpi_ac_seq_show(struct seq_file *seq, void *offset)
 110 {
 111         struct acpi_ac *ac = (struct acpi_ac *)seq->private;
 112
 113         ACPI_FUNCTION_TRACE("acpi_ac_seq_show");
 114
 115         if (!ac)
 116                 return_VALUE(0);
 117
 118         if (acpi_ac_get_state(ac)) {
 119                 seq_puts(seq, "ERROR: Unable to read AC Adapter state\n");
 120                 return_VALUE(0);
 121         }
 122
 123         seq_puts(seq, "state:                   ");
 124         switch (ac->state) {
 125         case ACPI_AC_STATUS_OFFLINE:
 126                 seq_puts(seq, "off-line\n");
 127                 break;
 128         case ACPI_AC_STATUS_ONLINE:
 129                 seq_puts(seq, "on-line\n");
 130                 break;
 131         default:
 132                 seq_puts(seq, "unknown\n");
 133                 break;
 134         }
 135
 136         return_VALUE(0);
 137 }
 138
 139 static int acpi_ac_open_fs(struct inode *inode, struct file *file)
 140 {
 141         return single_open(file, acpi_ac_seq_show, PDE(inode)->data);
 142 }
 143
 144 static int acpi_ac_add_fs(struct acpi_device *device)
 145 {
 146         struct proc_dir_entry *entry = NULL;
 147
 148         ACPI_FUNCTION_TRACE("acpi_ac_add_fs");
 149
 150         if (!acpi_device_dir(device)) {
 151                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 152                                                      acpi_ac_dir);
 153                 if (!acpi_device_dir(device))
 154                         return_VALUE(-ENODEV);
 155                 acpi_device_dir(device)->owner = THIS_MODULE;
 156         }
 157
 158         /* 'state' [R] */
 159         entry = create_proc_entry(ACPI_AC_FILE_STATE,
 160                                   S_IRUGO, acpi_device_dir(device));
 161         if (!entry)
 162                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
 163                                   "Unable to create '%s' fs entry\n",
 164                                   ACPI_AC_FILE_STATE));
 165         else {
 166                 entry->proc_fops = &acpi_ac_fops;
 167                 entry->data = acpi_driver_data(device);
 168                 entry->owner = THIS_MODULE;
 169         }
 170
 171         return_VALUE(0);
 172 }
 173
 174 static int acpi_ac_remove_fs(struct acpi_device *device)
 175 {
 176         ACPI_FUNCTION_TRACE("acpi_ac_remove_fs");
 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_VALUE(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 = (struct acpi_ac *)data;
 195         struct acpi_device *device = NULL;
 196
 197         ACPI_FUNCTION_TRACE("acpi_ac_notify");
 198
 199         if (!ac)
 200                 return_VOID;
 201
 202         if (acpi_bus_get_device(ac->handle, &device))
 203                 return_VOID;
 204
 205         switch (event) {
 206         case ACPI_AC_NOTIFY_STATUS:
 207                 acpi_ac_get_state(ac);
 208                 acpi_bus_generate_event(device, event, (u32) ac->state);
 209                 break;
 210         default:
 211                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 212                                   "Unsupported event [0x%x]\n", event));
 213                 break;
 214         }
 215
 216         return_VOID;
 217 }
 218
 219 static int acpi_ac_add(struct acpi_device *device)
 220 {
 221         int result = 0;
 222         acpi_status status = AE_OK;
 223         struct acpi_ac *ac = NULL;
 224
 225         ACPI_FUNCTION_TRACE("acpi_ac_add");
 226
 227         if (!device)
 228                 return_VALUE(-EINVAL);
 229
 230         ac = kmalloc(sizeof(struct acpi_ac), GFP_KERNEL);
 231         if (!ac)
 232                 return_VALUE(-ENOMEM);
 233         memset(ac, 0, sizeof(struct acpi_ac));
 234
 235         ac->handle = device->handle;
 236         strcpy(acpi_device_name(device), ACPI_AC_DEVICE_NAME);
 237         strcpy(acpi_device_class(device), ACPI_AC_CLASS);
 238         acpi_driver_data(device) = ac;
 239
 240         result = acpi_ac_get_state(ac);
 241         if (result)
 242                 goto end;
 243
 244         result = acpi_ac_add_fs(device);
 245         if (result)
 246                 goto end;
 247
 248         status = acpi_install_notify_handler(ac->handle,
 249                                              ACPI_DEVICE_NOTIFY, acpi_ac_notify,
 250                                              ac);
 251         if (ACPI_FAILURE(status)) {
 252                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
 253                                   "Error installing notify handler\n"));
 254                 result = -ENODEV;
 255                 goto end;
 256         }
 257
 258         printk(KERN_INFO PREFIX "%s [%s] (%s)\n",
 259                acpi_device_name(device), acpi_device_bid(device),
 260                ac->state ? "on-line" : "off-line");
 261
 262       end:
 263         if (result) {
 264                 acpi_ac_remove_fs(device);
 265                 kfree(ac);
 266         }
 267
 268         return_VALUE(result);
 269 }
 270
 271 static int acpi_ac_remove(struct acpi_device *device, int type)
 272 {
 273         acpi_status status = AE_OK;
 274         struct acpi_ac *ac = NULL;
 275
 276         ACPI_FUNCTION_TRACE("acpi_ac_remove");
 277
 278         if (!device || !acpi_driver_data(device))
 279                 return_VALUE(-EINVAL);
 280
 281         ac = (struct acpi_ac *)acpi_driver_data(device);
 282
 283         status = acpi_remove_notify_handler(ac->handle,
 284                                             ACPI_DEVICE_NOTIFY, acpi_ac_notify);
 285         if (ACPI_FAILURE(status))
 286                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
 287                                   "Error removing notify handler\n"));
 288
 289         acpi_ac_remove_fs(device);
 290
 291         kfree(ac);
 292
 293         return_VALUE(0);
 294 }
 295
 296 static int __init acpi_ac_init(void)
 297 {
 298         int result = 0;
 299
 300         ACPI_FUNCTION_TRACE("acpi_ac_init");
 301
 302         acpi_ac_dir = proc_mkdir(ACPI_AC_CLASS, acpi_root_dir);
 303         if (!acpi_ac_dir)
 304                 return_VALUE(-ENODEV);
 305         acpi_ac_dir->owner = THIS_MODULE;
 306
 307         result = acpi_bus_register_driver(&acpi_ac_driver);
 308         if (result < 0) {
 309                 remove_proc_entry(ACPI_AC_CLASS, acpi_root_dir);
 310                 return_VALUE(-ENODEV);
 311         }
 312
 313         return_VALUE(0);
 314 }
 315
 316 static void __exit acpi_ac_exit(void)
 317 {
 318         ACPI_FUNCTION_TRACE("acpi_ac_exit");
 319
 320         acpi_bus_unregister_driver(&acpi_ac_driver);
 321
 322         remove_proc_entry(ACPI_AC_CLASS, acpi_root_dir);
 323
 324         return_VOID;
 325 }
 326
 327 module_init(acpi_ac_init);
 328 module_exit(acpi_ac_exit);