At Wed, 07 Jun 2006 14:52:25 +0200, Johannes Berg wrote: > > On Wed, 2006-06-07 at 14:49 +0200, Takashi Iwai wrote: > > > Sorry, s/pci_to_dev/snd_dma_pci_data/ > > So then you're saying that indeed, snd_pcm_lib_preallocate_pages_for_all > has the side effect of setting a pointer somewhere else? Well, I don't understand what you mean "side-effect" here. The device pointer is passed to the memory allocator, so if you pass a bogus value there, it'll cause surely oops. > I just don't understand why it all blows up when I leave off the > preallocate call. From the function name that says 'preallocate pages' > it seemed to me that I should be allowed to just leave it off, risking > that later an open() or prepare() fails because no pages could be > allocated. IIF you use snd_pcm_lib_malloc_pages(), the pre-allocation is mandatory. That's the definition. (And, as mentioned, snd_pcm_lib_malloc_pages() checks the pre-allocation when debug option is set. If you don't set the debug option, it assumes that the pre-allocation was already executed.) You're free to use dma_alloc_coherent() or whatever in hw_params callback. Takashi _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.sourceforge.net/lists/listinfo/alsa-devel
