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  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
15  */
16 
17 #include <linux/kernel.h>
18 #include <linux/module.h>
19 #include <linux/init.h>
20 #include <linux/acpi.h>
21 #include <linux/types.h>
22 #include <linux/proc_fs.h>
23 #include <linux/seq_file.h>
24 #include <acpi/acpi_bus.h>
25 #include <acpi/acpi_drivers.h>
26 
27 #define PREFIX "ACPI: "
28 
29 ACPI_MODULE_NAME("cm_sbs");
30 #define ACPI_AC_CLASS		"ac_adapter"
31 #define ACPI_BATTERY_CLASS	"battery"
32 #define _COMPONENT		ACPI_SBS_COMPONENT
33 static struct proc_dir_entry *acpi_ac_dir;
34 static struct proc_dir_entry *acpi_battery_dir;
35 
36 static DEFINE_MUTEX(cm_sbs_mutex);
37 
38 static int lock_ac_dir_cnt;
39 static int lock_battery_dir_cnt;
40 
acpi_lock_ac_dir(void)41 struct proc_dir_entry *acpi_lock_ac_dir(void)
42 {
43 	mutex_lock(&cm_sbs_mutex);
44 	if (!acpi_ac_dir)
45 		acpi_ac_dir = proc_mkdir(ACPI_AC_CLASS, acpi_root_dir);
46 	if (acpi_ac_dir) {
47 		lock_ac_dir_cnt++;
48 	} else {
49 		printk(KERN_ERR PREFIX
50 				  "Cannot create %s\n", ACPI_AC_CLASS);
51 	}
52 	mutex_unlock(&cm_sbs_mutex);
53 	return acpi_ac_dir;
54 }
55 EXPORT_SYMBOL(acpi_lock_ac_dir);
56 
acpi_unlock_ac_dir(struct proc_dir_entry * acpi_ac_dir_param)57 void acpi_unlock_ac_dir(struct proc_dir_entry *acpi_ac_dir_param)
58 {
59 	mutex_lock(&cm_sbs_mutex);
60 	if (acpi_ac_dir_param)
61 		lock_ac_dir_cnt--;
62 	if (lock_ac_dir_cnt == 0 && acpi_ac_dir_param && acpi_ac_dir) {
63 		remove_proc_entry(ACPI_AC_CLASS, acpi_root_dir);
64 		acpi_ac_dir = NULL;
65 	}
66 	mutex_unlock(&cm_sbs_mutex);
67 }
68 EXPORT_SYMBOL(acpi_unlock_ac_dir);
69 
acpi_lock_battery_dir(void)70 struct proc_dir_entry *acpi_lock_battery_dir(void)
71 {
72 	mutex_lock(&cm_sbs_mutex);
73 	if (!acpi_battery_dir) {
74 		acpi_battery_dir =
75 		    proc_mkdir(ACPI_BATTERY_CLASS, acpi_root_dir);
76 	}
77 	if (acpi_battery_dir) {
78 		lock_battery_dir_cnt++;
79 	} else {
80 		printk(KERN_ERR PREFIX
81 				  "Cannot create %s\n", ACPI_BATTERY_CLASS);
82 	}
83 	mutex_unlock(&cm_sbs_mutex);
84 	return acpi_battery_dir;
85 }
86 EXPORT_SYMBOL(acpi_lock_battery_dir);
87 
acpi_unlock_battery_dir(struct proc_dir_entry * acpi_battery_dir_param)88 void acpi_unlock_battery_dir(struct proc_dir_entry *acpi_battery_dir_param)
89 {
90 	mutex_lock(&cm_sbs_mutex);
91 	if (acpi_battery_dir_param)
92 		lock_battery_dir_cnt--;
93 	if (lock_battery_dir_cnt == 0 && acpi_battery_dir_param
94 	    && acpi_battery_dir) {
95 		remove_proc_entry(ACPI_BATTERY_CLASS, acpi_root_dir);
96 		acpi_battery_dir = NULL;
97 	}
98 	mutex_unlock(&cm_sbs_mutex);
99 	return;
100 }
101 EXPORT_SYMBOL(acpi_unlock_battery_dir);
102