DMA feature question.

[James Courtier-Dutton <James@superbug.demon.co.uk>]

I have a sound card that requires access to 2 DMA areas per substream.
1) Is for the audio samples buffer. I can already do that with:

err = snd_pcm_lib_preallocate_pages(substream, SNDRV_DMA_TYPE_DEV, 
snd_dma_pci_data(emu->pci), 32*1024, 32*1024);


2) Is for a table of periods..
This table will contain:-
{ u32 Pointer_into_samples_buffer,
u32 number_of_bytes }
So, each record in the table is 8 bytes long, and identify each period 
in the buffer.

So, the table will contain a list of the different periods.
So, if there are 8 periods, the table will have 8 entries, each 8 bytes 
long, so I will need a DMA map for 64 bytes.

Is there any way to use the snd_pcm_lib_preallocate_pages() for this 
"table or periods".

If not, I will just have to make (1) a bit bigger, and place the "table 
of periods" in there.

Cheers

James


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