Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost
[cris-mirror.git] / arch / x86 / kernel / i8237.c
blob8eeaa81de0668cbb898bca660d344ffd148e0f28
1 /*
2 * 8237A DMA controller suspend functions.
4 * Written by Pierre Ossman, 2005.
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.
12 #include <linux/init.h>
13 #include <linux/syscore_ops.h>
15 #include <asm/dma.h>
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.
24 static void i8237A_resume(void)
26 unsigned long flags;
27 int i;
29 flags = claim_dma_lock();
31 dma_outb(0, DMA1_RESET_REG);
32 dma_outb(0, DMA2_RESET_REG);
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);
40 /* Enable cascade DMA or channel 0-3 won't work */
41 enable_dma(4);
43 release_dma_lock(flags);
46 static struct syscore_ops i8237_syscore_ops = {
47 .resume = i8237A_resume,
50 static int __init i8237A_init_ops(void)
52 register_syscore_ops(&i8237_syscore_ops);
53 return 0;
55 device_initcall(i8237A_init_ops);