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- /*
- * 8237A DMA controller suspend functions.
- *
- * Written by Pierre Ossman, 2005.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or (at
- * your option) any later version.
- */
- #include <linux/init.h>
- #include <linux/syscore_ops.h>
- #include <asm/dma.h>
- /*
- * This module just handles suspend/resume issues with the
- * 8237A DMA controller (used for ISA and LPC).
- * Allocation is handled in kernel/dma.c and normal usage is
- * in asm/dma.h.
- */
- static void i8237A_resume(void)
- {
- unsigned long flags;
- int i;
- flags = claim_dma_lock();
- dma_outb(0, DMA1_RESET_REG);
- dma_outb(0, DMA2_RESET_REG);
- for (i = 0; i < 8; i++) {
- set_dma_addr(i, 0x000000);
- /* DMA count is a bit weird so this is not 0 */
- set_dma_count(i, 1);
- }
- /* Enable cascade DMA or channel 0-3 won't work */
- enable_dma(4);
- release_dma_lock(flags);
- }
- static struct syscore_ops i8237_syscore_ops = {
- .resume = i8237A_resume,
- };
- static int __init i8237A_init_ops(void)
- {
- register_syscore_ops(&i8237_syscore_ops);
- return 0;
- }
- device_initcall(i8237A_init_ops);
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