From cc6a8acdeee932f6911d8b236d2c7d6bcc4616f6 Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Tue, 17 Jun 2008 16:39:06 +0200 Subject: ALSA: Fix SG-buffer DMA with non-coherent architectures Using SG-buffers with dma_alloc_coherent() is often very inefficient on non-coherent architectures because a tracking record could be allocated in addition for each dma_alloc_coherent() call. Instead, simply disable SG-buffers but just allocate normal continuous buffers on non-supported (currently all but x86) architectures. Signed-off-by: Takashi Iwai --- include/sound/pcm.h | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) (limited to 'include/sound/pcm.h') diff --git a/include/sound/pcm.h b/include/sound/pcm.h index 2389352..1691c7f 100644 --- a/include/sound/pcm.h +++ b/include/sound/pcm.h @@ -902,6 +902,7 @@ int snd_pcm_lib_preallocate_pages_for_all(struct snd_pcm *pcm, int snd_pcm_lib_malloc_pages(struct snd_pcm_substream *substream, size_t size); int snd_pcm_lib_free_pages(struct snd_pcm_substream *substream); +#ifdef CONFIG_SND_DMA_SGBUF /* * SG-buffer handling */ @@ -927,6 +928,28 @@ struct page *snd_pcm_sgbuf_ops_page(struct snd_pcm_substream *substream, unsigned int snd_pcm_sgbuf_get_chunk_size(struct snd_pcm_substream *substream, unsigned int ofs, unsigned int size); +#else /* !SND_DMA_SGBUF */ +/* + * fake using a continuous buffer + */ +static inline dma_addr_t +snd_pcm_sgbuf_get_addr(struct snd_pcm_substream *substream, unsigned int ofs) +{ + return substream->runtime->dma_addr + ofs; +} + +static inline void * +snd_pcm_sgbuf_get_ptr(struct snd_pcm_substream *substream, unsigned int ofs) +{ + return substream->runtime->dma_area + ofs; +} + +#define snd_pcm_sgbuf_ops_page NULL + +#define snd_pcm_sgbuf_get_chunk_size(subs, ofs, size) (size) + +#endif /* SND_DMA_SGBUF */ + /* handle mmap counter - PCM mmap callback should handle this counter properly */ static inline void snd_pcm_mmap_data_open(struct vm_area_struct *area) { -- cgit v1.1