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