drivers/acpi/cm_sbs.c

   1 /*
   2  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   3  *
   4  *  This program is free software; you can redistribute it and/or modify
   5  *  it under the terms of the GNU General Public License as published by
   6  *  the Free Software Foundation; either version 2 of the License, or (at
   7  *  your option) any later version.
   8  *
   9  *  This program is distributed in the hope that it will be useful, but
  10  *  WITHOUT ANY WARRANTY; without even the implied warranty of
  11  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  *  General Public License for more details.
  13  *
  14  *  You should have received a copy of the GNU General Public License along
  15  *  with this program; if not, write to the Free Software Foundation, Inc.,
  16  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  17  *
  18  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  19  */
  20
  21 #include <linux/kernel.h>
  22 #include <linux/module.h>
  23 #include <linux/init.h>
  24 #include <linux/acpi.h>
  25 #include <linux/types.h>
  26 #include <linux/proc_fs.h>
  27 #include <linux/seq_file.h>
  28 #include <acpi/acpi_bus.h>
  29 #include <acpi/acpi_drivers.h>
  30
  31 ACPI_MODULE_NAME("cm_sbs");
  32 #define ACPI_AC_CLASS           "ac_adapter"
  33 #define ACPI_BATTERY_CLASS      "battery"
  34 #define _COMPONENT              ACPI_SBS_COMPONENT
  35 static struct proc_dir_entry *acpi_ac_dir;
  36 static struct proc_dir_entry *acpi_battery_dir;
  37
  38 static DEFINE_MUTEX(cm_sbs_mutex);
  39
  40 static int lock_ac_dir_cnt;
  41 static int lock_battery_dir_cnt;
  42
  43 struct proc_dir_entry *acpi_lock_ac_dir(void)
  44 {
  45         mutex_lock(&cm_sbs_mutex);
  46         if (!acpi_ac_dir)
  47                 acpi_ac_dir = proc_mkdir(ACPI_AC_CLASS, acpi_root_dir);
  48         if (acpi_ac_dir) {
  49                 lock_ac_dir_cnt++;
  50         } else {
  51                 printk(KERN_ERR PREFIX
  52                                   "Cannot create %s\n", ACPI_AC_CLASS);
  53         }
  54         mutex_unlock(&cm_sbs_mutex);
  55         return acpi_ac_dir;
  56 }
  57 EXPORT_SYMBOL(acpi_lock_ac_dir);
  58
  59 void acpi_unlock_ac_dir(struct proc_dir_entry *acpi_ac_dir_param)
  60 {
  61         mutex_lock(&cm_sbs_mutex);
  62         if (acpi_ac_dir_param)
  63                 lock_ac_dir_cnt--;
  64         if (lock_ac_dir_cnt == 0 && acpi_ac_dir_param && acpi_ac_dir) {
  65                 remove_proc_entry(ACPI_AC_CLASS, acpi_root_dir);
  66                 acpi_ac_dir = NULL;
  67         }
  68         mutex_unlock(&cm_sbs_mutex);
  69 }
  70 EXPORT_SYMBOL(acpi_unlock_ac_dir);
  71
  72 struct proc_dir_entry *acpi_lock_battery_dir(void)
  73 {
  74         mutex_lock(&cm_sbs_mutex);
  75         if (!acpi_battery_dir) {
  76                 acpi_battery_dir =
  77                     proc_mkdir(ACPI_BATTERY_CLASS, acpi_root_dir);
  78         }
  79         if (acpi_battery_dir) {
  80                 lock_battery_dir_cnt++;
  81         } else {
  82                 printk(KERN_ERR PREFIX
  83                                   "Cannot create %s\n", ACPI_BATTERY_CLASS);
  84         }
  85         mutex_unlock(&cm_sbs_mutex);
  86         return acpi_battery_dir;
  87 }
  88 EXPORT_SYMBOL(acpi_lock_battery_dir);
  89
  90 void acpi_unlock_battery_dir(struct proc_dir_entry *acpi_battery_dir_param)
  91 {
  92         mutex_lock(&cm_sbs_mutex);
  93         if (acpi_battery_dir_param)
  94                 lock_battery_dir_cnt--;
  95         if (lock_battery_dir_cnt == 0 && acpi_battery_dir_param
  96             && acpi_battery_dir) {
  97                 remove_proc_entry(ACPI_BATTERY_CLASS, acpi_root_dir);
  98                 acpi_battery_dir = NULL;
  99         }
 100         mutex_unlock(&cm_sbs_mutex);
 101         return;
 102 }
 103 EXPORT_SYMBOL(acpi_unlock_battery_dir);