On Tue, 2010-04-27 at 10:28 -0500, Timur Tabi wrote: > Liam Girdwood wrote: > > > Iirc, the SSI and DMA controllers on your SoC mean that each DMA device > > can only do one direction (either Playback or Capture). So I'm thinking > > we create two DAI link entries for your sound card (one for playback and > > the other for capture) and they both use the same SSI device but each > > would have it's own DMA device. > > Do you mean here: > > machine_data->card.probe = mpc8610_hpcd_machine_probe; > machine_data->card.remove = mpc8610_hpcd_machine_remove; > machine_data->card.name = "MPC8610 HPCD"; > machine_data->card.num_links = 1; > machine_data->card.dai_link = &machine_data->dai; > > So that num_links would be 2 instead of 1? > Yes. > I would need some way for fsl_dma_open() to get a pointer to private, > DMA-specific data. I'm not sure how I can do that. > In multi-component we now have platform_data and device private data (from the regular driver model). We also have stream snd_soc_dai_set_dma_data() for runtime DMA config. So it depends on who is setting your DMA data. If it's DTS then it would be the of_ platform equivalent, if it's your DMA probe() then dev data otherwise you can use the snd_soc_dai_set_dma_data(). > > This would result in two separate pcm devices being exported to > > userspace i.e one for playback only and the other for capture only. I > > think this is also a more accurate representation of your hardware too > > (since we have different DMA devices for each pcm stream direction). > > I can say for certain whether that will actually work. My gut tells > me that I might run into problems trying to implement that. The only > way to know for sure is to start hacking. Unfortunately, my window of > opportunity to work on this just closed, and it may not open for a > while. I know my current patch is less-than-ideal, but it does > restore functionality to the 8610, and without needing any U-Boot or > device-tree changes. So unless there are any real objections, I'd > like it to be merged. Otherwise, 8610 audio will be broken in the > next release. Ok, I can live with this providing we can mark it as a TODO: and have a PPC Ack. It may be easier to fix in the future too as the ASoC card registration clean-up should be complete/in-progress (i.e. card platform_data and private_data will be available for passing in anything you like). Thanks Liam -- Freelance Developer, SlimLogic Ltd ASoC and Voltage Regulator Maintainer. http://www.slimlogic.co.uk _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
