On Mon, 29 Oct 2007, Alexander E. Patrakov wrote:
Even though mmap seems to be supported in the driver source (judging from .info = SNDRV_PCM_INFO_MMAP | other flags), I could not figure out the parameters that work. Moreover, the driver seems to accept the same hardware parameters without the mmap, and I could not find parameters that the driver accepts for mmap.
I do not think the saa7134-alsa driver supports mmap. The cx88-alsa driver also claimed to support mmap, but it never worked until I fixed it. It's pretty clear that the code in saa7134-alsa was based on the same code as cx88-alsa, so it's likely it has the same bug.
One more question: since plug doesn't work at all on devices without mmap available, does this mean that I should scrap my original idea about using plug to convert everything into S24?
Does plug require mmap? It does it just require that devices which claim to support mmap actually work in mmap mode?