/* * 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/core.h> #include <sound/pcm.h> #include "devdma.h" void devdma_hw_free(struct device *dev, struct snd_pcm_substream *substream) { struct snd_pcm_runtime *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, struct snd_pcm_substream *substream, size_t size) { struct snd_pcm_runtime *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, struct snd_pcm_substream *substream, struct vm_area_struct *vma) { struct snd_pcm_runtime *runtime = substream->runtime; return dma_mmap_coherent(dev, vma, runtime->dma_area, runtime->dma_addr, runtime->dma_bytes); }