Hi Robert > So the next issue I'm now facing is that the MCLK to SCLK divider is not being > set properly in either the Audio Formatter (MM2S Fs Multiplier register) or in > the I2S Transmitter (I2S Timing Control register). The xlnx_i2s driver has a > set_clkdiv function defined in its snd_soc_dai_ops structure, however that > doesn't appear to be getting called. And the xlnx_formatter_pcm driver doesn't > seem to have any code to set XLNX_AUD_FS_MULTIPLIER at all. > > In this case I have a sample rate to MCLK divider of 256, so it looks like I > should add mclk-fs = <256> into the dai-link nodes in the device tree, but > there will need to be some code added to the xlnx_formatter_pcm to do something > with that information? And then should that driver have code to trigger the > call to set_clkdiv on the CPU DAI as well? > > These drivers originated in the Xilinx kernel tree ( > https://jpn01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgithub.com%2FXilinx%2Flinux-xlnx%2Ftree%2Fmaster%2Fsound%2Fsoc%2Fxilinx&data=04%7C01%7Ckuninori.morimoto.gx%40renesas.com%7C48c9c4633dae479df6a408d9424d9abd%7C53d82571da1947e49cb4625a166a4a2a%7C0%7C0%7C637613723347710960%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&sdata=nMnJI78dvM12Yj8mqB8TzJfxtm3V1tUeJpVQ1FR1bhE%3D&reserved=0) and in that > tree they've got a top-level xlnx_pl_snd_card.c driver which is defining the > MCLK divider and instantiating the other components, however that driver is not > in mainline and seems like it is kind of a hack. It seems like this SCLK > divider setting is the main thing that is still needed to getting the Xilinx > audio cores working in mainline using simple-sound-card.. Hmm... clock is one of difficult point to be generic, I guess. audio-graph / audio-graph2 has customize feature in such case, but simple-card doesn't. - create generic clock handling way on simple-card ? - add customize feature to simple-card ? - switch to audio-graph / audio-graph2, and use customize feature ? Thank you for your help !! Best regards --- Kuninori Morimoto
