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/*
* 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(-EIO);
}
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 {
ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
"Unable to create '%s' proc fs entry\n","event" ));
error = -EFAULT;
}
return_VALUE(error);
}
subsys_initcall(acpi_event_init);
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