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
  88         if (!ac)
  89                 return -EINVAL;
  90
  91         status = acpi_evaluate_integer(ac->handle, "_PSR", NULL, &ac->state);
  92         if (ACPI_FAILURE(status)) {
  93                 ACPI_EXCEPTION((AE_INFO, status, "Error reading AC Adapter state"));
  94                 ac->state = ACPI_AC_STATUS_UNKNOWN;
  95                 return -ENODEV;
  96         }
  97
  98         return 0;
  99 }
 100
 101 /* --------------------------------------------------------------------------
 102                               FS Interface (/proc)
 103    -------------------------------------------------------------------------- */
 104
 105 static struct proc_dir_entry *acpi_ac_dir;
 106
 107 static int acpi_ac_seq_show(struct seq_file *seq, void *offset)
 108 {
 109         struct acpi_ac *ac = (struct acpi_ac *)seq->private;
 110
 111
 112         if (!ac)
 113                 return 0;
 114
 115         if (acpi_ac_get_state(ac)) {
 116                 seq_puts(seq, "ERROR: Unable to read AC Adapter state\n");
 117                 return 0;
 118         }
 119
 120         seq_puts(seq, "state:                   ");
 121         switch (ac->state) {
 122         case ACPI_AC_STATUS_OFFLINE:
 123                 seq_puts(seq, "off-line\n");
 124                 break;
 125         case ACPI_AC_STATUS_ONLINE:
 126                 seq_puts(seq, "on-line\n");
 127                 break;
 128         default:
 129                 seq_puts(seq, "unknown\n");
 130                 break;
 131         }
 132
 133         return 0;
 134 }
 135
 136 static int acpi_ac_open_fs(struct inode *inode, struct file *file)
 137 {
 138         return single_open(file, acpi_ac_seq_show, PDE(inode)->data);
 139 }
 140
 141 static int acpi_ac_add_fs(struct acpi_device *device)
 142 {
 143         struct proc_dir_entry *entry = NULL;
 144
 145
 146         if (!acpi_device_dir(device)) {
 147                 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
 148                                                      acpi_ac_dir);
 149                 if (!acpi_device_dir(device))
 150                         return -ENODEV;
 151                 acpi_device_dir(device)->owner = THIS_MODULE;
 152         }
 153
 154         /* 'state' [R] */
 155         entry = create_proc_entry(ACPI_AC_FILE_STATE,
 156                                   S_IRUGO, acpi_device_dir(device));
 157         if (!entry)
 158                 return -ENODEV;
 159         else {
 160                 entry->proc_fops = &acpi_ac_fops;
 161                 entry->data = acpi_driver_data(device);
 162                 entry->owner = THIS_MODULE;
 163         }
 164
 165         return 0;
 166 }
 167
 168 static int acpi_ac_remove_fs(struct acpi_device *device)
 169 {
 170
 171         if (acpi_device_dir(device)) {
 172                 remove_proc_entry(ACPI_AC_FILE_STATE, acpi_device_dir(device));
 173
 174                 remove_proc_entry(acpi_device_bid(device), acpi_ac_dir);
 175                 acpi_device_dir(device) = NULL;
 176         }
 177
 178         return 0;
 179 }
 180
 181 /* --------------------------------------------------------------------------
 182                                    Driver Model
 183    -------------------------------------------------------------------------- */
 184
 185 static void acpi_ac_notify(acpi_handle handle, u32 event, void *data)
 186 {
 187         struct acpi_ac *ac = (struct acpi_ac *)data;
 188         struct acpi_device *device = NULL;
 189
 190
 191         if (!ac)
 192                 return;
 193
 194         if (acpi_bus_get_device(ac->handle, &device))
 195                 return;
 196
 197         switch (event) {
 198         case ACPI_AC_NOTIFY_STATUS:
 199                 acpi_ac_get_state(ac);
 200                 acpi_bus_generate_event(device, event, (u32) ac->state);
 201                 break;
 202         default:
 203                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 204                                   "Unsupported event [0x%x]\n", event));
 205                 break;
 206         }
 207
 208         return;
 209 }
 210
 211 static int acpi_ac_add(struct acpi_device *device)
 212 {
 213         int result = 0;
 214         acpi_status status = AE_OK;
 215         struct acpi_ac *ac = NULL;
 216
 217
 218         if (!device)
 219                 return -EINVAL;
 220
 221         ac = kmalloc(sizeof(struct acpi_ac), GFP_KERNEL);
 222         if (!ac)
 223                 return -ENOMEM;
 224         memset(ac, 0, sizeof(struct acpi_ac));
 225
 226         ac->handle = device->handle;
 227         strcpy(acpi_device_name(device), ACPI_AC_DEVICE_NAME);
 228         strcpy(acpi_device_class(device), ACPI_AC_CLASS);
 229         acpi_driver_data(device) = ac;
 230
 231         result = acpi_ac_get_state(ac);
 232         if (result)
 233                 goto end;
 234
 235         result = acpi_ac_add_fs(device);
 236         if (result)
 237                 goto end;
 238
 239         status = acpi_install_notify_handler(ac->handle,
 240                                              ACPI_DEVICE_NOTIFY, acpi_ac_notify,
 241                                              ac);
 242         if (ACPI_FAILURE(status)) {
 243                 result = -ENODEV;
 244                 goto end;
 245         }
 246
 247         printk(KERN_INFO PREFIX "%s [%s] (%s)\n",
 248                acpi_device_name(device), acpi_device_bid(device),
 249                ac->state ? "on-line" : "off-line");
 250
 251       end:
 252         if (result) {
 253                 acpi_ac_remove_fs(device);
 254                 kfree(ac);
 255         }
 256
 257         return result;
 258 }
 259
 260 static int acpi_ac_remove(struct acpi_device *device, int type)
 261 {
 262         acpi_status status = AE_OK;
 263         struct acpi_ac *ac = NULL;
 264
 265
 266         if (!device || !acpi_driver_data(device))
 267                 return -EINVAL;
 268
 269         ac = (struct acpi_ac *)acpi_driver_data(device);
 270
 271         status = acpi_remove_notify_handler(ac->handle,
 272                                             ACPI_DEVICE_NOTIFY, acpi_ac_notify);
 273
 274         acpi_ac_remove_fs(device);
 275
 276         kfree(ac);
 277
 278         return 0;
 279 }
 280
 281 static int __init acpi_ac_init(void)
 282 {
 283         int result = 0;
 284
 285
 286         acpi_ac_dir = proc_mkdir(ACPI_AC_CLASS, acpi_root_dir);
 287         if (!acpi_ac_dir)
 288                 return -ENODEV;
 289         acpi_ac_dir->owner = THIS_MODULE;
 290
 291         result = acpi_bus_register_driver(&acpi_ac_driver);
 292         if (result < 0) {
 293                 remove_proc_entry(ACPI_AC_CLASS, acpi_root_dir);
 294                 return -ENODEV;
 295         }
 296
 297         return 0;
 298 }
 299
 300 static void __exit acpi_ac_exit(void)
 301 {
 302
 303         acpi_bus_unregister_driver(&acpi_ac_driver);
 304
 305         remove_proc_entry(ACPI_AC_CLASS, acpi_root_dir);
 306
 307         return;
 308 }
 309
 310 module_init(acpi_ac_init);
 311 module_exit(acpi_ac_exit);