Hello, I am trying to allocate memory for DMA buffer through "snd_pcm_lib_malloc_pages" in hw_params callout function, with prior use of "snd_pcm_lib_preallocate_pages_for_all". The chapter on PCM Interface in "writing an ALSA driver" states that if the standard function "snd_pcm_lib_malloc_pages" is use for allocating the DMA buffers then the DMA fields of dma_addr, dma_area, dma_bytes are set by the ALSA middle layer. However my code walk through didn't point me to the area where this physical memory setting is done. My DMA channel is not serving a PCI device. I would be very grateful if any of you guys can point me to the code where this settings get done by calling "snd_pcm_lib_malloc_pages". Going through the code for a few devices registered under "pci" I found that the call to "snd_pcm_lib_malloc_pages" is followed by call to "snd_pcm_sgbuf_get_addr" to get the physical address. Also a call to "__pa" is done in the "parisc/harmony.c". Do I have to set the dma parameters in the runtime structure even after allocating memory using "snd_pcm_lib_malloc_pages"? Regards; Aadish _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
