Hi Sylwester > > Is the main difference between "normal" and DPCM card that in case of the > > former the data flow routes are static and the latter allows dynamic > > reconfiguration of sound data routes? AFAIU DPCM stands here for Dynamic > > PCM [1], rather than Differential Pulse Code Modulation. > > DPCM is a Linux internal abstraction that doesn't represent what's going > on in a very generic fashion which makes it problematic when it appears > directly in DT bindings. It's very SoC centric. > > > It seems the graph based binding could cover above both cases. Apologies > > if this has been explained before, but what are main reasons for introducing > > the graph based binding? > > The simple card is creaking at the seams as it was only really designed > to represent very simple use cases but has been extended rather beyond > that. It's also not set up to cope with things like CODEC<->CODEC links > that don't involve the CPU as it really only has the idea of point to > point links between a CPU DAI and a CODEC DAI. > > > Is the SCU part in "ASoC simple SCU Sound Card" derived from "(S)ample Rate > > (C)onverter (U)nit" ? > > Yes. The original driver was created for Renesas SCU feature which needed DPCM's .be_hw_params_fixup() for converting. It was created based on simple card. At first, it was created as Renesas specific sound card, but I changed/moved it to one of simple card. Then I named it as simple scu card. Best regards --- Kuninori Morimoto -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html