int DMAbuf_open(int dev, int mode)
{
struct audio_operations *adev = audio_devs[dev];
int retval;
struct dma_buffparms *dmap_in = NULL;
struct dma_buffparms *dmap_out = NULL;
if (!adev)
return -ENXIO;
if (!(adev->flags & DMA_DUPLEX))
adev->dmap_in = adev->dmap_out;
check_driver(adev->d);
if ((retval = adev->d->open(dev, mode)) < 0)
return retval;
dmap_out = adev->dmap_out;
dmap_in = adev->dmap_in;
if (dmap_in == dmap_out)
adev->flags &= ~DMA_DUPLEX;
if (mode & OPEN_WRITE) {
if ((retval = open_dmap(adev, mode, dmap_out)) < 0) {
adev->d->close(dev);
return retval;
}
}
adev->enable_bits = mode;
if (mode == OPEN_READ || (mode != OPEN_WRITE && (adev->flags & DMA_DUPLEX))) {
if ((retval = open_dmap(adev, mode, dmap_in)) < 0) {
adev->d->close(dev);
if (mode & OPEN_WRITE)
close_dmap(adev, dmap_out);
return retval;
}
}
adev->open_mode = mode;
adev->go = 1;
adev->d->set_bits(dev, 8);
adev->d->set_channels(dev, 1);
adev->d->set_speed(dev, DSP_DEFAULT_SPEED);
if (adev->dmap_out->dma_mode == DMODE_OUTPUT)
memset(adev->dmap_out->raw_buf, adev->dmap_out->neutral_byte,
adev->dmap_out->bytes_in_use);
return 0;
}
int DMAbuf_open_dma(int dev)
{
/*
* NOTE! This routine opens only the primary DMA channel (output).
*/
struct audio_operations *adev = audio_devs[dev];
int err;
if ((err = open_dmap(adev, OPEN_READWRITE, adev->dmap_out)) < 0)
return -EBUSY;
dma_init_buffers(adev->dmap_out);
adev->dmap_out->flags |= DMA_ALLOC_DONE;
adev->dmap_out->fragment_size = adev->dmap_out->buffsize;
if (adev->dmap_out->dma >= 0) {
unsigned long flags;
flags=claim_dma_lock();
clear_dma_ff(adev->dmap_out->dma);
disable_dma(adev->dmap_out->dma);
release_dma_lock(flags);
}
return 0;
}