drivers/acpi/cm_sbs.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2
   3 #include <linux/kernel.h>
   4 #include <linux/module.h>
   5 #include <linux/init.h>
   6 #include <linux/acpi.h>
   7 #include <linux/types.h>
   8 #include <linux/proc_fs.h>
   9 #include <linux/seq_file.h>
  10 #include <acpi/acpi_bus.h>
  11 #include <acpi/acpi_drivers.h>
  12
  13 #define PREFIX "ACPI: "
  14
  15 ACPI_MODULE_NAME("cm_sbs");
  16 #define ACPI_AC_CLASS           "ac_adapter"
  17 #define ACPI_BATTERY_CLASS      "battery"
  18 #define _COMPONENT              ACPI_SBS_COMPONENT
  19 static struct proc_dir_entry *acpi_ac_dir;
  20 static struct proc_dir_entry *acpi_battery_dir;
  21
  22 static DEFINE_MUTEX(cm_sbs_mutex);
  23
  24 static int lock_ac_dir_cnt;
  25 static int lock_battery_dir_cnt;
  26
  27 struct proc_dir_entry *acpi_lock_ac_dir(void)
  28 {
  29         mutex_lock(&cm_sbs_mutex);
  30         if (!acpi_ac_dir)
  31                 acpi_ac_dir = proc_mkdir(ACPI_AC_CLASS, acpi_root_dir);
  32         if (acpi_ac_dir) {
  33                 lock_ac_dir_cnt++;
  34         } else {
  35                 printk(KERN_ERR PREFIX
  36                                   "Cannot create %s\n", ACPI_AC_CLASS);
  37         }
  38         mutex_unlock(&cm_sbs_mutex);
  39         return acpi_ac_dir;
  40 }
  41 EXPORT_SYMBOL(acpi_lock_ac_dir);
  42
  43 void acpi_unlock_ac_dir(struct proc_dir_entry *acpi_ac_dir_param)
  44 {
  45         mutex_lock(&cm_sbs_mutex);
  46         if (acpi_ac_dir_param)
  47                 lock_ac_dir_cnt--;
  48         if (lock_ac_dir_cnt == 0 && acpi_ac_dir_param && acpi_ac_dir) {
  49                 remove_proc_entry(ACPI_AC_CLASS, acpi_root_dir);
  50                 acpi_ac_dir = NULL;
  51         }
  52         mutex_unlock(&cm_sbs_mutex);
  53 }
  54 EXPORT_SYMBOL(acpi_unlock_ac_dir);
  55
  56 struct proc_dir_entry *acpi_lock_battery_dir(void)
  57 {
  58         mutex_lock(&cm_sbs_mutex);
  59         if (!acpi_battery_dir) {
  60                 acpi_battery_dir =
  61                     proc_mkdir(ACPI_BATTERY_CLASS, acpi_root_dir);
  62         }
  63         if (acpi_battery_dir) {
  64                 lock_battery_dir_cnt++;
  65         } else {
  66                 printk(KERN_ERR PREFIX
  67                                   "Cannot create %s\n", ACPI_BATTERY_CLASS);
  68         }
  69         mutex_unlock(&cm_sbs_mutex);
  70         return acpi_battery_dir;
  71 }
  72 EXPORT_SYMBOL(acpi_lock_battery_dir);
  73
  74 void acpi_unlock_battery_dir(struct proc_dir_entry *acpi_battery_dir_param)
  75 {
  76         mutex_lock(&cm_sbs_mutex);
  77         if (acpi_battery_dir_param)
  78                 lock_battery_dir_cnt--;
  79         if (lock_battery_dir_cnt == 0 && acpi_battery_dir_param
  80             && acpi_battery_dir) {
  81                 remove_proc_entry(ACPI_BATTERY_CLASS, acpi_root_dir);
  82                 acpi_battery_dir = NULL;
  83         }
  84         mutex_unlock(&cm_sbs_mutex);
  85         return;
  86 }
  87 EXPORT_SYMBOL(acpi_unlock_battery_dir);