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authorThomas Gleixner <tglx@linutronix.de>2007-10-11 05:17:01 -0400
committerThomas Gleixner <tglx@linutronix.de>2007-10-11 05:17:01 -0400
commit9a163ed8e0552fdcffe405d2ea7134819a81456e (patch)
treeb322fd2afbb812ba7ddfd22f3734aaab007c2aa5 /arch/x86/kernel/i8237.c
parentf7627e2513987bb5d4e8cb13c4e0a478352141ac (diff)
i386: move kernel
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'arch/x86/kernel/i8237.c')
-rw-r--r--arch/x86/kernel/i8237.c72
1 files changed, 72 insertions, 0 deletions
diff --git a/arch/x86/kernel/i8237.c b/arch/x86/kernel/i8237.c
new file mode 100644
index 000000000000..6f508e8d7c57
--- /dev/null
+++ b/arch/x86/kernel/i8237.c
@@ -0,0 +1,72 @@
1/*
2 * i8237.c: 8237A DMA controller suspend functions.
3 *
4 * Written by Pierre Ossman, 2005.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or (at
9 * your option) any later version.
10 */
11
12#include <linux/init.h>
13#include <linux/sysdev.h>
14
15#include <asm/dma.h>
16
17/*
18 * This module just handles suspend/resume issues with the
19 * 8237A DMA controller (used for ISA and LPC).
20 * Allocation is handled in kernel/dma.c and normal usage is
21 * in asm/dma.h.
22 */
23
24static int i8237A_resume(struct sys_device *dev)
25{
26 unsigned long flags;
27 int i;
28
29 flags = claim_dma_lock();
30
31 dma_outb(DMA1_RESET_REG, 0);
32 dma_outb(DMA2_RESET_REG, 0);
33
34 for (i = 0;i < 8;i++) {
35 set_dma_addr(i, 0x000000);
36 /* DMA count is a bit weird so this is not 0 */
37 set_dma_count(i, 1);
38 }
39
40 /* Enable cascade DMA or channel 0-3 won't work */
41 enable_dma(4);
42
43 release_dma_lock(flags);
44
45 return 0;
46}
47
48static int i8237A_suspend(struct sys_device *dev, pm_message_t state)
49{
50 return 0;
51}
52
53static struct sysdev_class i8237_sysdev_class = {
54 set_kset_name("i8237"),
55 .suspend = i8237A_suspend,
56 .resume = i8237A_resume,
57};
58
59static struct sys_device device_i8237A = {
60 .id = 0,
61 .cls = &i8237_sysdev_class,
62};
63
64static int __init i8237A_init_sysfs(void)
65{
66 int error = sysdev_class_register(&i8237_sysdev_class);
67 if (!error)
68 error = sysdev_register(&device_i8237A);
69 return error;
70}
71
72device_initcall(i8237A_init_sysfs);