[alsa-devel] DMA Physical Address through "snd_pcm_lib_malloc_pages"

Takashi Iwai tiwai at suse.de
Thu Jun 24 09:15:28 CEST 2010

At Thu, 24 Jun 2010 12:38:35 +0530,
Adish Kuvelker wrote:
> Hello Takashi,
> I am developing a DMA Controller driver to service the PCM out data to
> the Audio controller on the arm-based ATLASIII procesor. In case you
> need any more information on the architecture I can pass.
> Since the DMA isn't on PCI bus I am pre-allocation continuous memero
> using the "snd_pcm_lib_preallocate_pages_for_all" passing
> SNDDRV_DMA_TYPE_DEV and "snd_dma_continuous_data" as appropriate
> parameters.

snd_dma_continuous_data() is only for SNDRV_DMA_TYPE_CONTINUOUS.
In this case, the pages aren't for DMA.

For SNDRV_DMA_TYPE_DEV, simply pass the device pointer you use.


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