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 #include <acpi/acmacros.h>
  31 #include <acpi/actypes.h>
  32 #include <acpi/acutils.h>
  33
  34 ACPI_MODULE_NAME("cm_sbs");
  35 #define ACPI_AC_CLASS           "ac_adapter"
  36 #define ACPI_BATTERY_CLASS      "battery"
  37 #define _COMPONENT              ACPI_SBS_COMPONENT
  38 static struct proc_dir_entry *acpi_ac_dir;
  39 static struct proc_dir_entry *acpi_battery_dir;
  40
  41 static DEFINE_MUTEX(cm_sbs_mutex);
  42
  43 static int lock_ac_dir_cnt;
  44 static int lock_battery_dir_cnt;
  45
  46 struct proc_dir_entry *acpi_lock_ac_dir(void)
  47 {
  48         mutex_lock(&cm_sbs_mutex);
  49         if (!acpi_ac_dir)
  50                 acpi_ac_dir = proc_mkdir(ACPI_AC_CLASS, acpi_root_dir);
  51         if (acpi_ac_dir) {
  52                 lock_ac_dir_cnt++;
  53         } else {
  54                 printk(KERN_ERR PREFIX
  55                                   "Cannot create %s\n", ACPI_AC_CLASS);
  56         }
  57         mutex_unlock(&cm_sbs_mutex);
  58         return acpi_ac_dir;
  59 }
  60 EXPORT_SYMBOL(acpi_lock_ac_dir);
  61
  62 void acpi_unlock_ac_dir(struct proc_dir_entry *acpi_ac_dir_param)
  63 {
  64         mutex_lock(&cm_sbs_mutex);
  65         if (acpi_ac_dir_param)
  66                 lock_ac_dir_cnt--;
  67         if (lock_ac_dir_cnt == 0 && acpi_ac_dir_param && acpi_ac_dir) {
  68                 remove_proc_entry(ACPI_AC_CLASS, acpi_root_dir);
  69                 acpi_ac_dir = NULL;
  70         }
  71         mutex_unlock(&cm_sbs_mutex);
  72 }
  73 EXPORT_SYMBOL(acpi_unlock_ac_dir);
  74
  75 struct proc_dir_entry *acpi_lock_battery_dir(void)
  76 {
  77         mutex_lock(&cm_sbs_mutex);
  78         if (!acpi_battery_dir) {
  79                 acpi_battery_dir =
  80                     proc_mkdir(ACPI_BATTERY_CLASS, acpi_root_dir);
  81         }
  82         if (acpi_battery_dir) {
  83                 lock_battery_dir_cnt++;
  84         } else {
  85                 printk(KERN_ERR PREFIX
  86                                   "Cannot create %s\n", ACPI_BATTERY_CLASS);
  87         }
  88         mutex_unlock(&cm_sbs_mutex);
  89         return acpi_battery_dir;
  90 }
  91 EXPORT_SYMBOL(acpi_lock_battery_dir);
  92
  93 void acpi_unlock_battery_dir(struct proc_dir_entry *acpi_battery_dir_param)
  94 {
  95         mutex_lock(&cm_sbs_mutex);
  96         if (acpi_battery_dir_param)
  97                 lock_battery_dir_cnt--;
  98         if (lock_battery_dir_cnt == 0 && acpi_battery_dir_param
  99             && acpi_battery_dir) {
 100                 remove_proc_entry(ACPI_BATTERY_CLASS, acpi_root_dir);
 101                 acpi_battery_dir = NULL;
 102         }
 103         mutex_unlock(&cm_sbs_mutex);
 104         return;
 105 }
 106 EXPORT_SYMBOL(acpi_unlock_battery_dir);