[linux.git] / drivers / acpi / event.c

/*
 * event.c - exporting ACPI events via procfs
 *
 *  Copyright (C) 2001, 2002 Andy Grover <[email protected]>
 *  Copyright (C) 2001, 2002 Paul Diefenbaugh <[email protected]>
 *
 */

#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;


	if (!chars_remaining) {
		memset(&event, 0, sizeof(struct acpi_bus_event));

		if ((file->f_flags & O_NONBLOCK)
		    && (list_empty(&acpi_bus_event_list)))
			return -EAGAIN;

		result = acpi_bus_receive_event(&event);
		if (result)
			return 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 -EFAULT;

	*ppos += count;
	chars_remaining -= count;
	ptr += count;

	return 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 const 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;


	if (acpi_disabled)
		return 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 error;
}

subsys_initcall(acpi_event_init);
Commit	Line	Data
1da177e4 LT	1	/*
	2	* event.c - exporting ACPI events via procfs
	3	*
	4	* Copyright (C) 2001, 2002 Andy Grover <[email protected]>
	5	* Copyright (C) 2001, 2002 Paul Diefenbaugh <[email protected]>
	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;
1da177e4 LT	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,
4be44fcd LB	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	50
1da177e4 LT	51
	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)))
d550d98d	57	return -EAGAIN;
1da177e4 LT	58
1da177e4 LT	59	result = acpi_bus_receive_event(&event);
5cc9eeef	60	if (result)
d550d98d	61	return result;
1da177e4	62
4be44fcd LB	63	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);
1da177e4 LT	69	ptr = str;
	70	}
	71
	72	if (chars_remaining < count) {
	73	count = chars_remaining;
	74	}
	75
	76	if (copy_to_user(buffer, ptr, count))
d550d98d	77	return -EFAULT;
1da177e4 LT	78
	79	*ppos += count;
	80	chars_remaining -= count;
	81	ptr += count;
	82
d550d98d	83	return count;
1da177e4 LT	84	}
1da177e4 LT	85
4be44fcd	86	static int acpi_system_close_event(struct inode inode, struct file file)
1da177e4	87	{
4be44fcd	88	spin_lock_irq(&acpi_system_event_lock);
1da177e4	89	event_is_open = 0;
4be44fcd	90	spin_unlock_irq(&acpi_system_event_lock);
1da177e4 LT	91	return 0;
	92	}
	93
4be44fcd	94	static unsigned int acpi_system_poll_event(struct file file, poll_table wait)
1da177e4 LT	95	{
	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
d7508032	102	static const struct file_operations acpi_system_event_ops = {
4be44fcd LB	103	.open = acpi_system_open_event,
	104	.read = acpi_system_read_event,
	105	.release = acpi_system_close_event,
	106	.poll = acpi_system_poll_event,
1da177e4 LT	107	};
	108
	109	static int __init acpi_event_init(void)
	110	{
4be44fcd	111	struct proc_dir_entry *entry;
1da177e4 LT	112	int error = 0;
1da177e4 LT	113
1da177e4 LT	114
1da177e4 LT	115	if (acpi_disabled)
d550d98d	116	return 0;
1da177e4 LT	117
	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 {
a6fc6720	123	error = -ENODEV;
1da177e4	124	}
d550d98d	125	return error;
1da177e4 LT	126	}
	127
	128	subsys_initcall(acpi_event_init);