topic Re: IMX6UL, linux configuration for two codecs on a single SAI in i.MX Processors

IMX6UL, linux configuration for two codecs on a single SAI

jmsebastian — Fri, 03 May 2019 10:50:45 GMT

Hi there,

I am working on a custom platform with a iMX6UL processor. I need to connect two codecs, each one with two DACs and two ADCs, to the same SAI. I need to send/receive pcm data to/from both codecs simultaneously, so I need to use TDM mode with 4 words.

I am not being able to write a correct device tree: if I set two dai-links (something similar to this link: https://community.nxp.com/message/1126123?commentID=1126123#comment-1126123), one for each codec, I cannot use both simultaneously. An error is displayed for the second playback, saying that sai is already in use.

Is it possible to use sai + tdm + 2 codecs simultaneously with current linux drivers of SAI? How should I configure the device tree?

Any help will be highy appreciated.

Regards,

Miguel

Re: IMX6UL, linux configuration for two codecs on a single SAI

igorpadykov — Fri, 03 May 2019 23:38:31 GMT

Hi Miguel

>Is it possible to use sai + tdm + 2 codecs simultaneously with current linux drivers of SAI?

I am afraid such configuration is not supported in current linux.

In general sai driver supports multiple slots in linux/sound/soc/fsl/fsl_sai.c

fsl_sai.c\fsl\soc\sound - linux-imx - i.MX Linux kernel

.."slots = sai->slots"..

so one can try to debug it.

Also several codecs should be connected appropriately using sai clocks/data description in

Figure 42-1. I2S/SAI block diagram i.MX6UL Reference Manual

http://www.nxp.com/docs/en/reference-manual/IMX6ULRM.pdf

Best regards
igor
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Re: IMX6UL, linux configuration for two codecs on a single SAI

jmsebastian — Thu, 09 May 2019 09:25:18 GMT

Thanks for your anser, Igor.

I'll try to debug it, as you suggest.

Best Regards,

Miguel