On Mon, Nov 24, 2008 at 03:45:33PM +0200, Jarkko Nikula wrote: > My problem was this kind of switching correct to do in machine driver? > cpu_dai->playback.channels_min = 1; > cpu_dai->playback.channels_max = 1; > cpu_dai->capture.channels_min = 1; > cpu_dai->capture.channels_max = 1; No, these should be constant. Any dynamic constraints should be applied with the constraints API. > Defining channels_min = 1 in omap_mcbsp_dai initializer would cause that > link is then switching between mono/stereo depending what user space is > asking. Yes. > Like "aplay -c 1 /dev/urandom" causes that all machines having codec > with "channels_min = 1" and "channels_max = 2" would cause incorrect > mono link configuration where alsalib should do the mono->stereo > conversion instead and vice versa for pure mono link. So, this is a bit messy at the moment since we don't really have any DAPM-style routing on the digital side yet. What most of these codecs should probably be doing is declaring a 2 channel minimuim - normally that's what they require as a wire format even if they only actually use the data from one of those channels. This will be less efficient when these devices are used in a mono configuration but is safer until we can map out the digital side better in software; it's roughly what you're trying to do here on the CPU side. _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
