]>
Commit | Line | Data |
---|---|---|
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 | |
16 | ACPI_MODULE_NAME ("event") | |
17 | ||
18 | /* Global vars for handling event proc entry */ | |
19 | static DEFINE_SPINLOCK(acpi_system_event_lock); | |
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; | |
23 | ||
24 | static int | |
25 | acpi_system_open_event(struct inode *inode, struct file *file) | |
26 | { | |
c65ade4d | 27 | spin_lock_irq(&acpi_system_event_lock); |
1da177e4 | 28 | |
c65ade4d | 29 | if (event_is_open) |
1da177e4 LT |
30 | goto out_busy; |
31 | ||
32 | event_is_open = 1; | |
33 | ||
c65ade4d | 34 | spin_unlock_irq(&acpi_system_event_lock); |
1da177e4 LT |
35 | return 0; |
36 | ||
37 | out_busy: | |
c65ade4d | 38 | spin_unlock_irq(&acpi_system_event_lock); |
1da177e4 LT |
39 | return -EBUSY; |
40 | } | |
41 | ||
42 | static ssize_t | |
c65ade4d | 43 | acpi_system_read_event(struct file *file, char __user *buffer, size_t count, loff_t *ppos) |
1da177e4 LT |
44 | { |
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; | |
50 | ||
51 | ||
52 | ACPI_FUNCTION_TRACE("acpi_system_read_event"); | |
53 | ||
54 | if (!chars_remaining) { | |
55 | memset(&event, 0, sizeof(struct acpi_bus_event)); | |
56 | ||
57 | if ((file->f_flags & O_NONBLOCK) | |
58 | && (list_empty(&acpi_bus_event_list))) | |
59 | return_VALUE(-EAGAIN); | |
60 | ||
61 | result = acpi_bus_receive_event(&event); | |
62 | if (result) { | |
63 | return_VALUE(-EIO); | |
64 | } | |
65 | ||
66 | chars_remaining = sprintf(str, "%s %s %08x %08x\n", | |
67 | event.device_class?event.device_class:"<unknown>", | |
68 | event.bus_id?event.bus_id:"<unknown>", | |
69 | event.type, event.data); | |
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 | ||
87 | static int | |
88 | acpi_system_close_event(struct inode *inode, struct file *file) | |
89 | { | |
90 | spin_lock_irq (&acpi_system_event_lock); | |
91 | event_is_open = 0; | |
92 | spin_unlock_irq (&acpi_system_event_lock); | |
93 | return 0; | |
94 | } | |
95 | ||
96 | static unsigned int | |
c65ade4d | 97 | acpi_system_poll_event(struct file *file, poll_table *wait) |
1da177e4 LT |
98 | { |
99 | poll_wait(file, &acpi_bus_event_queue, wait); | |
100 | if (!list_empty(&acpi_bus_event_list)) | |
101 | return POLLIN | POLLRDNORM; | |
102 | return 0; | |
103 | } | |
104 | ||
105 | static struct file_operations acpi_system_event_ops = { | |
106 | .open = acpi_system_open_event, | |
107 | .read = acpi_system_read_event, | |
108 | .release = acpi_system_close_event, | |
109 | .poll = acpi_system_poll_event, | |
110 | }; | |
111 | ||
112 | static int __init acpi_event_init(void) | |
113 | { | |
114 | struct proc_dir_entry *entry; | |
115 | int error = 0; | |
116 | ||
117 | ACPI_FUNCTION_TRACE("acpi_event_init"); | |
118 | ||
119 | if (acpi_disabled) | |
120 | return_VALUE(0); | |
121 | ||
122 | /* 'event' [R] */ | |
123 | entry = create_proc_entry("event", S_IRUSR, acpi_root_dir); | |
124 | if (entry) | |
125 | entry->proc_fops = &acpi_system_event_ops; | |
126 | else { | |
127 | ACPI_DEBUG_PRINT((ACPI_DB_ERROR, | |
128 | "Unable to create '%s' proc fs entry\n","event" )); | |
129 | error = -EFAULT; | |
130 | } | |
131 | return_VALUE(error); | |
132 | } | |
133 | ||
134 | subsys_initcall(acpi_event_init); |