irqdomain: Remove powerpc dependency from debugfs file
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / arch / um / kernel / sigio.c
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8e367065 1/*
c5d4bb17 2 * Copyright (C) 2002 - 2007 Jeff Dike (jdike@{linux.intel,addtoit}.com)
1da177e4
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3 * Licensed under the GPL
4 */
5
c5d4bb17 6#include <linux/interrupt.h>
1da177e4 7#include "irq_kern.h"
8e367065 8#include "os.h"
c5d4bb17 9#include "sigio.h"
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10
11/* Protected by sigio_lock() called from write_sigio_workaround */
12static int sigio_irq_fd = -1;
13
7bea96fd 14static irqreturn_t sigio_interrupt(int irq, void *data)
1da177e4 15{
8e367065
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16 char c;
17
a6ea4cce 18 os_read_file(sigio_irq_fd, &c, sizeof(c));
1da177e4 19 reactivate_fd(sigio_irq_fd, SIGIO_WRITE_IRQ);
4cffb7fa 20 return IRQ_HANDLED;
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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,
c0b79a90 28 IRQF_SAMPLE_RANDOM, "write sigio",
1da177e4 29 NULL);
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30 if (err) {
31 printk(KERN_ERR "write_sigio_irq : um_request_irq failed, "
32 "err = %d\n", err);
4cffb7fa 33 return -1;
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34 }
35 sigio_irq_fd = fd;
4cffb7fa 36 return 0;
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37}
38
d9f9d319 39/* These are called from os-Linux/sigio.c to protect its pollfds arrays. */
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40static DEFINE_SPINLOCK(sigio_spinlock);
41
42void sigio_lock(void)
43{
44 spin_lock(&sigio_spinlock);
45}
46
47void sigio_unlock(void)
48{
49 spin_unlock(&sigio_spinlock);
50}