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Hi,
I'm writing an ALSA driver using no pci or isa
preallocation memory (i'm using
snd_pcm_lib_preallocate_pages_for_all).
I've some questions according to the alsa mecanism
to transfert datas.
I'm using ALSA 0.9.6
when i send a wav file to the /dev/audio0
file:
dd if=ring.wav of=/dev/audio0
In my ops function, i've added:
snd_....._playback_copy(snd_pcm_substream_t
*substream, int channel, snd_pcm_uframes_t pos, void* src, snd_pcm_uframes_t
count) 1) Why the src pointer doesn't point to the data
source (the ring.wav data) when this function is called by ALSA.
2) why the count parameter is always 200? is
it possible to change this offset in order to copy more data?
3) it seams more complicated to manage memory than
using pci or isa preallocation.
Could i use one of these structure ethen if i don't
have ISA or PCI bus/dma on my board?
Thanks in advance.
Mathieu Rondonneau
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