blob: a901b23e95e7b38e53378e5af4140182ab6cd86f [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
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
Len Brown4be44fc2005-08-05 00:44:28 -040016ACPI_MODULE_NAME("event")
Linus Torvalds1da177e2005-04-16 15:20:36 -070017
18/* Global vars for handling event proc entry */
19static DEFINE_SPINLOCK(acpi_system_event_lock);
Len Brown4be44fc2005-08-05 00:44:28 -040020int event_is_open = 0;
21extern struct list_head acpi_bus_event_list;
22extern wait_queue_head_t acpi_bus_event_queue;
Linus Torvalds1da177e2005-04-16 15:20:36 -070023
Len Brown4be44fc2005-08-05 00:44:28 -040024static int acpi_system_open_event(struct inode *inode, struct file *file)
Linus Torvalds1da177e2005-04-16 15:20:36 -070025{
Pavel Machekc65ade42005-08-05 00:37:45 -040026 spin_lock_irq(&acpi_system_event_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -070027
Pavel Machekc65ade42005-08-05 00:37:45 -040028 if (event_is_open)
Linus Torvalds1da177e2005-04-16 15:20:36 -070029 goto out_busy;
30
31 event_is_open = 1;
32
Pavel Machekc65ade42005-08-05 00:37:45 -040033 spin_unlock_irq(&acpi_system_event_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -070034 return 0;
35
Len Brown4be44fc2005-08-05 00:44:28 -040036 out_busy:
Pavel Machekc65ade42005-08-05 00:37:45 -040037 spin_unlock_irq(&acpi_system_event_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -070038 return -EBUSY;
39}
40
41static ssize_t
Len Brown4be44fc2005-08-05 00:44:28 -040042acpi_system_read_event(struct file *file, char __user * buffer, size_t count,
43 loff_t * ppos)
Linus Torvalds1da177e2005-04-16 15:20:36 -070044{
Len Brown4be44fc2005-08-05 00:44:28 -040045 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;
Linus Torvalds1da177e2005-04-16 15:20:36 -070050
Linus Torvalds1da177e2005-04-16 15:20:36 -070051
52 if (!chars_remaining) {
53 memset(&event, 0, sizeof(struct acpi_bus_event));
54
55 if ((file->f_flags & O_NONBLOCK)
56 && (list_empty(&acpi_bus_event_list)))
Patrick Mocheld550d982006-06-27 00:41:40 -040057 return -EAGAIN;
Linus Torvalds1da177e2005-04-16 15:20:36 -070058
59 result = acpi_bus_receive_event(&event);
Pavel Machek5cc9eee2005-10-17 16:43:31 -070060 if (result)
Patrick Mocheld550d982006-06-27 00:41:40 -040061 return result;
Linus Torvalds1da177e2005-04-16 15:20:36 -070062
Len Brown4be44fc2005-08-05 00:44:28 -040063 chars_remaining = sprintf(str, "%s %s %08x %08x\n",
64 event.device_class ? event.
65 device_class : "<unknown>",
66 event.bus_id ? event.
67 bus_id : "<unknown>", event.type,
68 event.data);
Linus Torvalds1da177e2005-04-16 15:20:36 -070069 ptr = str;
70 }
71
72 if (chars_remaining < count) {
73 count = chars_remaining;
74 }
75
76 if (copy_to_user(buffer, ptr, count))
Patrick Mocheld550d982006-06-27 00:41:40 -040077 return -EFAULT;
Linus Torvalds1da177e2005-04-16 15:20:36 -070078
79 *ppos += count;
80 chars_remaining -= count;
81 ptr += count;
82
Patrick Mocheld550d982006-06-27 00:41:40 -040083 return count;
Linus Torvalds1da177e2005-04-16 15:20:36 -070084}
85
Len Brown4be44fc2005-08-05 00:44:28 -040086static int acpi_system_close_event(struct inode *inode, struct file *file)
Linus Torvalds1da177e2005-04-16 15:20:36 -070087{
Len Brown4be44fc2005-08-05 00:44:28 -040088 spin_lock_irq(&acpi_system_event_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -070089 event_is_open = 0;
Len Brown4be44fc2005-08-05 00:44:28 -040090 spin_unlock_irq(&acpi_system_event_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -070091 return 0;
92}
93
Len Brown4be44fc2005-08-05 00:44:28 -040094static unsigned int acpi_system_poll_event(struct file *file, poll_table * wait)
Linus Torvalds1da177e2005-04-16 15:20:36 -070095{
96 poll_wait(file, &acpi_bus_event_queue, wait);
97 if (!list_empty(&acpi_bus_event_list))
98 return POLLIN | POLLRDNORM;
99 return 0;
100}
101
102static struct file_operations acpi_system_event_ops = {
Len Brown4be44fc2005-08-05 00:44:28 -0400103 .open = acpi_system_open_event,
104 .read = acpi_system_read_event,
105 .release = acpi_system_close_event,
106 .poll = acpi_system_poll_event,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700107};
108
109static int __init acpi_event_init(void)
110{
Len Brown4be44fc2005-08-05 00:44:28 -0400111 struct proc_dir_entry *entry;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700112 int error = 0;
113
Linus Torvalds1da177e2005-04-16 15:20:36 -0700114
115 if (acpi_disabled)
Patrick Mocheld550d982006-06-27 00:41:40 -0400116 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700117
118 /* 'event' [R] */
119 entry = create_proc_entry("event", S_IRUSR, acpi_root_dir);
120 if (entry)
121 entry->proc_fops = &acpi_system_event_ops;
122 else {
Thomas Renningera6fc6722006-06-26 23:58:43 -0400123 error = -ENODEV;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700124 }
Patrick Mocheld550d982006-06-27 00:41:40 -0400125 return error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700126}
127
128subsys_initcall(acpi_event_init);