sndbuf_dma.c

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/*-
 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
 *
 * Copyright (c) 1999 Cameron Grant <cg@freebsd.org>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */
 
#ifdef HAVE_KERNEL_OPTION_HEADERS
#include "opt_snd.h"
#endif
 
#include <dev/sound/pcm/sound.h>
 
#include <isa/isavar.h>
 
SND_DECLARE_FILE("$FreeBSD$");
 
int
sndbuf_dmasetup(struct snd_dbuf *b, struct resource *drq)
{
        /* should do isa_dma_acquire/isa_dma_release here */
        if (drq == NULL) {
                b->dmachan = -1;
        } else {
                sndbuf_setflags(b, SNDBUF_F_DMA, 1);
                b->dmachan = rman_get_start(drq);
        }
        return 0;
}
 
int
sndbuf_dmasetdir(struct snd_dbuf *b, int dir)
{
        KASSERT(b, ("sndbuf_dmasetdir called with b == NULL"));
        KASSERT(sndbuf_getflags(b) & SNDBUF_F_DMA, ("sndbuf_dmasetdir called on non-ISA buffer"));
 
        b->dir = (dir == PCMDIR_PLAY)? ISADMA_WRITE : ISADMA_READ;
        return 0;
}
 
void
sndbuf_dma(struct snd_dbuf *b, int go)
{
        KASSERT(b, ("sndbuf_dma called with b == NULL"));
        KASSERT(sndbuf_getflags(b) & SNDBUF_F_DMA, ("sndbuf_dma called on non-ISA buffer"));
 
        switch (go) {
        case PCMTRIG_START:
                /* isa_dmainit(b->chan, size); */
                isa_dmastart(b->dir | ISADMA_RAW, b->buf, b->bufsize, b->dmachan);
                break;
 
        case PCMTRIG_STOP:
        case PCMTRIG_ABORT:
                isa_dmastop(b->dmachan);
                isa_dmadone(b->dir | ISADMA_RAW, b->buf, b->bufsize, b->dmachan);
                break;
        }
 
        DEB(printf("buf 0x%p ISA DMA %s, channel %d\n",
                b,
                (go == PCMTRIG_START)? "started" : "stopped",
                b->dmachan));
}
 
int
sndbuf_dmaptr(struct snd_dbuf *b)
{
        int i;
 
        KASSERT(b, ("sndbuf_dmaptr called with b == NULL"));
        KASSERT(sndbuf_getflags(b) & SNDBUF_F_DMA, ("sndbuf_dmaptr called on non-ISA buffer"));
 
        if (!sndbuf_runsz(b))
                return 0;
        i = isa_dmastatus(b->dmachan);
        KASSERT(i >= 0, ("isa_dmastatus returned %d", i));
        return b->bufsize - i;
}
 
void
sndbuf_dmabounce(struct snd_dbuf *b)
{
        KASSERT(b, ("sndbuf_dmabounce called with b == NULL"));
        KASSERT(sndbuf_getflags(b) & SNDBUF_F_DMA, ("sndbuf_dmabounce called on non-ISA buffer"));
 
        /* tell isa_dma to bounce data in/out */
}