On Thu, Mar 21, 2013 at 04:06:27PM +0100, Lars-Peter Clausen wrote:
Hm, I only saw this series today would have been good to be on Cc. I've been working on something very similar. My series goes a bit further though, it implements an (almost generic) dmaengine based PCM driver using the of bindings. So you need almost no platform code. The only things that are platform specific at the moment is the pcm_hardware struct, but I'd like to replace that in the future with something that queries the pcm hardware parameter like max_period from the DMA engine driver. And another bit that is still driver specific is a callback that fills the dma_slave_config struct.
FWIW it might be worth looking at the one rmk wrote but has never wanted to submit for whatever reason.
In my series the channels are requested at probe time, so it is possible to handle -EPROBE_DEFER properly and also we can allocate the audio buffers with the dma device instead of the sound device, so stupid hacks like
card->dev->dma_mask = &dma_mask; card->dev->coherent_dma_mask = DMA_BIT_MASK(32);
anymore. I'll try to post the series tomorrow.
This is the main thing his code has got that the library hasn't, it's certainly the only issue he keeps mentioning.