Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * event.c - exporting ACPI events via procfs | |
3 | * | |
4 | * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com> | |
5 | * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com> | |
6 | * | |
7 | */ | |
8 | ||
9 | #include <linux/spinlock.h> | |
10 | #include <linux/proc_fs.h> | |
11 | #include <linux/init.h> | |
12 | #include <linux/poll.h> | |
13 | #include <acpi/acpi_drivers.h> | |
14 | ||
15 | #define _COMPONENT ACPI_SYSTEM_COMPONENT | |
4be44fcd | 16 | ACPI_MODULE_NAME("event") |
1da177e4 LT |
17 | |
18 | /* Global vars for handling event proc entry */ | |
19 | static DEFINE_SPINLOCK(acpi_system_event_lock); | |
4be44fcd LB |
20 | int event_is_open = 0; |
21 | extern struct list_head acpi_bus_event_list; | |
22 | extern wait_queue_head_t acpi_bus_event_queue; | |
1da177e4 | 23 | |
4be44fcd | 24 | static int acpi_system_open_event(struct inode *inode, struct file *file) |
1da177e4 | 25 | { |
c65ade4d | 26 | spin_lock_irq(&acpi_system_event_lock); |
1da177e4 | 27 | |
c65ade4d | 28 | if (event_is_open) |
1da177e4 LT |
29 | goto out_busy; |
30 | ||
31 | event_is_open = 1; | |
32 | ||
c65ade4d | 33 | spin_unlock_irq(&acpi_system_event_lock); |
1da177e4 LT |
34 | return 0; |
35 | ||
4be44fcd | 36 | out_busy: |
c65ade4d | 37 | spin_unlock_irq(&acpi_system_event_lock); |
1da177e4 LT |
38 | return -EBUSY; |
39 | } | |
40 | ||
41 | static ssize_t | |
4be44fcd LB |
42 | acpi_system_read_event(struct file *file, char __user * buffer, size_t count, |
43 | loff_t * ppos) | |
1da177e4 | 44 | { |
4be44fcd LB |
45 | int result = 0; |
46 | struct acpi_bus_event event; | |
47 | static char str[ACPI_MAX_STRING]; | |
48 | static int chars_remaining = 0; | |
49 | static char *ptr; | |
1da177e4 LT |
50 | |
51 | ACPI_FUNCTION_TRACE("acpi_system_read_event"); | |
52 | ||
53 | if (!chars_remaining) { | |
54 | memset(&event, 0, sizeof(struct acpi_bus_event)); | |
55 | ||
56 | if ((file->f_flags & O_NONBLOCK) | |
57 | && (list_empty(&acpi_bus_event_list))) | |
58 | return_VALUE(-EAGAIN); | |
59 | ||
60 | result = acpi_bus_receive_event(&event); | |
5cc9eeef PM |
61 | if (result) |
62 | return_VALUE(result); | |
1da177e4 | 63 | |
4be44fcd LB |
64 | chars_remaining = sprintf(str, "%s %s %08x %08x\n", |
65 | event.device_class ? event. | |
66 | device_class : "<unknown>", | |
67 | event.bus_id ? event. | |
68 | bus_id : "<unknown>", event.type, | |
69 | event.data); | |
1da177e4 LT |
70 | ptr = str; |
71 | } | |
72 | ||
73 | if (chars_remaining < count) { | |
74 | count = chars_remaining; | |
75 | } | |
76 | ||
77 | if (copy_to_user(buffer, ptr, count)) | |
78 | return_VALUE(-EFAULT); | |
79 | ||
80 | *ppos += count; | |
81 | chars_remaining -= count; | |
82 | ptr += count; | |
83 | ||
84 | return_VALUE(count); | |
85 | } | |
86 | ||
4be44fcd | 87 | static int acpi_system_close_event(struct inode *inode, struct file *file) |
1da177e4 | 88 | { |
4be44fcd | 89 | spin_lock_irq(&acpi_system_event_lock); |
1da177e4 | 90 | event_is_open = 0; |
4be44fcd | 91 | spin_unlock_irq(&acpi_system_event_lock); |
1da177e4 LT |
92 | return 0; |
93 | } | |
94 | ||
4be44fcd | 95 | static unsigned int acpi_system_poll_event(struct file *file, poll_table * wait) |
1da177e4 LT |
96 | { |
97 | poll_wait(file, &acpi_bus_event_queue, wait); | |
98 | if (!list_empty(&acpi_bus_event_list)) | |
99 | return POLLIN | POLLRDNORM; | |
100 | return 0; | |
101 | } | |
102 | ||
103 | static struct file_operations acpi_system_event_ops = { | |
4be44fcd LB |
104 | .open = acpi_system_open_event, |
105 | .read = acpi_system_read_event, | |
106 | .release = acpi_system_close_event, | |
107 | .poll = acpi_system_poll_event, | |
1da177e4 LT |
108 | }; |
109 | ||
110 | static int __init acpi_event_init(void) | |
111 | { | |
4be44fcd | 112 | struct proc_dir_entry *entry; |
1da177e4 LT |
113 | int error = 0; |
114 | ||
115 | ACPI_FUNCTION_TRACE("acpi_event_init"); | |
116 | ||
117 | if (acpi_disabled) | |
118 | return_VALUE(0); | |
119 | ||
120 | /* 'event' [R] */ | |
121 | entry = create_proc_entry("event", S_IRUSR, acpi_root_dir); | |
122 | if (entry) | |
123 | entry->proc_fops = &acpi_system_event_ops; | |
124 | else { | |
4be44fcd LB |
125 | ACPI_DEBUG_PRINT((ACPI_DB_ERROR, |
126 | "Unable to create '%s' proc fs entry\n", | |
127 | "event")); | |
1da177e4 LT |
128 | error = -EFAULT; |
129 | } | |
130 | return_VALUE(error); | |
131 | } | |
132 | ||
133 | subsys_initcall(acpi_event_init); |