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