1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
|
/*
* event.c - exporting ACPI events via procfs
*
* Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
* Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
*
*/
#include <linux/spinlock.h>
#include <linux/proc_fs.h>
#include <linux/init.h>
#include <linux/poll.h>
#include <acpi/acpi_drivers.h>
#define _COMPONENT ACPI_SYSTEM_COMPONENT
ACPI_MODULE_NAME("event")
/* Global vars for handling event proc entry */
static DEFINE_SPINLOCK(acpi_system_event_lock);
int event_is_open = 0;
extern struct list_head acpi_bus_event_list;
extern wait_queue_head_t acpi_bus_event_queue;
static int acpi_system_open_event(struct inode *inode, struct file *file)
{
spin_lock_irq(&acpi_system_event_lock);
if (event_is_open)
goto out_busy;
event_is_open = 1;
spin_unlock_irq(&acpi_system_event_lock);
return 0;
out_busy:
spin_unlock_irq(&acpi_system_event_lock);
return -EBUSY;
}
static ssize_t
acpi_system_read_event(struct file *file, char __user * buffer, size_t count,
loff_t * ppos)
{
int result = 0;
struct acpi_bus_event event;
static char str[ACPI_MAX_STRING];
static int chars_remaining = 0;
static char *ptr;
ACPI_FUNCTION_TRACE("acpi_system_read_event");
if (!chars_remaining) {
memset(&event, 0, sizeof(struct acpi_bus_event));
if ((file->f_flags & O_NONBLOCK)
&& (list_empty(&acpi_bus_event_list)))
return_VALUE(-EAGAIN);
result = acpi_bus_receive_event(&event);
if (result)
return_VALUE(result);
chars_remaining = sprintf(str, "%s %s %08x %08x\n",
event.device_class ? event.
device_class : "<unknown>",
event.bus_id ? event.
bus_id : "<unknown>", event.type,
event.data);
ptr = str;
}
if (chars_remaining < count) {
count = chars_remaining;
}
if (copy_to_user(buffer, ptr, count))
return_VALUE(-EFAULT);
*ppos += count;
chars_remaining -= count;
ptr += count;
return_VALUE(count);
}
static int acpi_system_close_event(struct inode *inode, struct file *file)
{
spin_lock_irq(&acpi_system_event_lock);
event_is_open = 0;
spin_unlock_irq(&acpi_system_event_lock);
return 0;
}
static unsigned int acpi_system_poll_event(struct file *file, poll_table * wait)
{
poll_wait(file, &acpi_bus_event_queue, wait);
if (!list_empty(&acpi_bus_event_list))
return POLLIN | POLLRDNORM;
return 0;
}
static struct file_operations acpi_system_event_ops = {
.open = acpi_system_open_event,
.read = acpi_system_read_event,
.release = acpi_system_close_event,
.poll = acpi_system_poll_event,
};
static int __init acpi_event_init(void)
{
struct proc_dir_entry *entry;
int error = 0;
ACPI_FUNCTION_TRACE("acpi_event_init");
if (acpi_disabled)
return_VALUE(0);
/* 'event' [R] */
entry = create_proc_entry("event", S_IRUSR, acpi_root_dir);
if (entry)
entry->proc_fops = &acpi_system_event_ops;
else {
error = -ENODEV;
}
return_VALUE(error);
}
subsys_initcall(acpi_event_init);
|
