[alsa-devel] Buffer memory does not get allocated?

Radivoje Jovanovic radivojejovanovic at gmail.com
Thu Nov 4 22:12:33 CET 2010

I am allocating memory for the buffers in my init call by doing:
snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_CONTINUOUS,
snd_dma_continuous_data(GFP_KERNEL), 256*1024, 256*1024);

in my hw_params call I have:
ret= snd_pcm_lib_malloc_pages(substream, params_buffer_bytes(hw_params));

here is the output from my hw_params call:

called snd_pcm_lib_malloc_pages return=1

Size of DMA area=32768

Buffer size in bytes=262144

Buffer virt address=9dc00000

Buffer phys address=0

Now I am not sure why is my buffer size bigger than my DMA area. I assume
that memory is not linear because of that and that is why I do not have phys
address to the buffer. How do I fix this?


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