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authorTakashi Iwai <tiwai@suse.de>2008-06-17 16:39:06 +0200
committerTakashi Iwai <tiwai@suse.de>2009-07-08 14:20:20 +0200
commitcc6a8acdeee932f6911d8b236d2c7d6bcc4616f6 (patch)
treeebaadf1a406cf073fd4ce59d5f1f20d499f9cde1 /include/sound/pcm.h
parent8e4a718ff38d8539938ec3421935904c27e00c39 (diff)
downloadlwn-cc6a8acdeee932f6911d8b236d2c7d6bcc4616f6.tar.gz
lwn-cc6a8acdeee932f6911d8b236d2c7d6bcc4616f6.zip
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 <tiwai@suse.de>
Diffstat (limited to 'include/sound/pcm.h')
-rw-r--r--include/sound/pcm.h23
1 files changed, 23 insertions, 0 deletions
diff --git a/include/sound/pcm.h b/include/sound/pcm.h
index 23893523dc8c..1691c7fe35af 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)
{