On Mon, Oct 20, 2008 at 02:51:04PM +0200, John Kacur wrote: > On Mon, Oct 20, 2008 at 2:40 PM, Mark Brown <broonie@xxxxxxxxxxxxx> wrote: > >> There is however no sound card, thus no PCM device. Now the question > >> is how to proceed? In other words what kind of minimal PCM layer do I > >> need if any? > > Could you please clarify what you're attempting to do here? > On a simple level, I'm just trying to provide sound, by implementing > an alsa driver. I've implemented a low-level library that can > manipulate all my hardware's i2s registers, and I've been mirroring > other alsa-soc drivers, and I'm at the point where I'm scratching my > head over what to do about PCM. The confusion to me, is that the code > seems to describe actually hardware - and the only thing I can think > of it what my hardware i2s is capable of transmitting, does that sound > right? I think you've misunderstood how this is supposed to work. None of the drivers for I2S or DMA controllers are responsible for creating a sound card by themselves. They provide support for the features of the I2S or DMA controller but then rely on a separate machine driver to describe how they are actually connected into the system. There's some documentation of the model that's being used here in: Documentation/sound/alsa/soc In your case you'll want to implement I2S and DMA drivers for your platform and a codec driver for the MAX5556 (looking at the datasheet it has no control of its own but you'll need to provide a DAI for it) and then provide a machine driver which connects them together. _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
