1/*
2 * Copyright (C) 2002 - 2007 Jeff Dike (jdike@{linux.intel,addtoit}.com)
3 * Licensed under the GPL
4 */
5
6#include <linux/interrupt.h>
7#include <irq_kern.h>
8#include <os.h>
9#include <sigio.h>
10
11/* Protected by sigio_lock() called from write_sigio_workaround */
12static int sigio_irq_fd = -1;
13
14static irqreturn_t sigio_interrupt(int irq, void *data)
15{
16	char c;
17
18	os_read_file(sigio_irq_fd, &c, sizeof(c));
19	reactivate_fd(sigio_irq_fd, SIGIO_WRITE_IRQ);
20	return IRQ_HANDLED;
21}
22
23int write_sigio_irq(int fd)
24{
25	int err;
26
27	err = um_request_irq(SIGIO_WRITE_IRQ, fd, IRQ_READ, sigio_interrupt,
28			     0, "write sigio", NULL);
29	if (err) {
30		printk(KERN_ERR "write_sigio_irq : um_request_irq failed, "
31		       "err = %d\n", err);
32		return -1;
33	}
34	sigio_irq_fd = fd;
35	return 0;
36}
37
38/* These are called from os-Linux/sigio.c to protect its pollfds arrays. */
39static DEFINE_SPINLOCK(sigio_spinlock);
40
41void sigio_lock(void)
42{
43	spin_lock(&sigio_spinlock);
44}
45
46void sigio_unlock(void)
47{
48	spin_unlock(&sigio_spinlock);
49}
50