Subversion Repositories or1k_soc_on_altera_embedded_dev_kit

/*

 * 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/sysdev.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 int i8237A_resume(struct sys_device *dev)

{

        unsigned long flags;

        int i;

        flags = claim_dma_lock();

        dma_outb(DMA1_RESET_REG, 0);

        dma_outb(DMA2_RESET_REG, 0);

        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);

        return 0;

}

static int i8237A_suspend(struct sys_device *dev, pm_message_t state)

{

        return 0;

}

static struct sysdev_class i8237_sysdev_class = {

        set_kset_name("i8237"),

        .suspend = i8237A_suspend,

        .resume = i8237A_resume,

};

static struct sys_device device_i8237A = {

        .id     = 0,

        .cls    = &i8237_sysdev_class,

};

static int __init i8237A_init_sysfs(void)

{

        int error = sysdev_class_register(&i8237_sysdev_class);

        if (!error)

                error = sysdev_register(&device_i8237A);

        return error;

}

device_initcall(i8237A_init_sysfs);