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