9b9a5afffd
ARM DMA routines The patch below adds a convenient re-usable shim around the extended ARM DMA API, and is used by several ARM ALSA drivers. Signed-off-by: Russell King <rmk@arm.linux.org.uk> Signed-off-by: Takashi Iwai <tiwai@suse.de>
81 lines
2 KiB
C
81 lines
2 KiB
C
/*
|
|
* linux/sound/arm/devdma.c
|
|
*
|
|
* Copyright (C) 2003-2004 Russell King, All rights reserved.
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
* published by the Free Software Foundation.
|
|
*
|
|
* ARM DMA shim for ALSA.
|
|
*/
|
|
#include <linux/device.h>
|
|
#include <linux/dma-mapping.h>
|
|
|
|
#include <sound/driver.h>
|
|
#include <sound/core.h>
|
|
#include <sound/pcm.h>
|
|
|
|
#include "devdma.h"
|
|
|
|
void devdma_hw_free(struct device *dev, snd_pcm_substream_t *substream)
|
|
{
|
|
snd_pcm_runtime_t *runtime = substream->runtime;
|
|
struct snd_dma_buffer *buf = runtime->dma_buffer_p;
|
|
|
|
if (runtime->dma_area == NULL)
|
|
return;
|
|
|
|
if (buf != &substream->dma_buffer) {
|
|
dma_free_coherent(buf->dev.dev, buf->bytes, buf->area, buf->addr);
|
|
kfree(runtime->dma_buffer_p);
|
|
}
|
|
|
|
snd_pcm_set_runtime_buffer(substream, NULL);
|
|
}
|
|
|
|
int devdma_hw_alloc(struct device *dev, snd_pcm_substream_t *substream, size_t size)
|
|
{
|
|
snd_pcm_runtime_t *runtime = substream->runtime;
|
|
struct snd_dma_buffer *buf = runtime->dma_buffer_p;
|
|
int ret = 0;
|
|
|
|
if (buf) {
|
|
if (buf->bytes >= size)
|
|
goto out;
|
|
devdma_hw_free(dev, substream);
|
|
}
|
|
|
|
if (substream->dma_buffer.area != NULL && substream->dma_buffer.bytes >= size) {
|
|
buf = &substream->dma_buffer;
|
|
} else {
|
|
buf = kmalloc(sizeof(struct snd_dma_buffer), GFP_KERNEL);
|
|
if (!buf)
|
|
goto nomem;
|
|
|
|
buf->dev.type = SNDRV_DMA_TYPE_DEV;
|
|
buf->dev.dev = dev;
|
|
buf->area = dma_alloc_coherent(dev, size, &buf->addr, GFP_KERNEL);
|
|
buf->bytes = size;
|
|
buf->private_data = NULL;
|
|
|
|
if (!buf->area)
|
|
goto free;
|
|
}
|
|
snd_pcm_set_runtime_buffer(substream, buf);
|
|
ret = 1;
|
|
out:
|
|
runtime->dma_bytes = size;
|
|
return ret;
|
|
|
|
free:
|
|
kfree(buf);
|
|
nomem:
|
|
return -ENOMEM;
|
|
}
|
|
|
|
int devdma_mmap(struct device *dev, snd_pcm_substream_t *substream, struct vm_area_struct *vma)
|
|
{
|
|
snd_pcm_runtime_t *runtime = substream->runtime;
|
|
return dma_mmap_coherent(dev, vma, runtime->dma_area, runtime->dma_addr, runtime->dma_bytes);
|
|
}
|