Surround Audio over SPDIF, HDMI and I2S

Hello,

Is it possible to have 4ch or more output from firefly? As far as I see from RK3288 datasheet it is possible through I2S but SPDIF just has has two channels. And what about HDMI, I couldnt see any information, as far as I know HDMI uses same output like SPDIF so it has to be 2 channels as well.

Could you please clarify these?

Thank you.

Hello,

The RK3288 can provide up to 4 I2S outputs. If you look at page 12 of the Firefly board schematics you can see that only I2S_SDO0 is connected to the processor pins. So having 4 channels or more would require these channels to be interleaved on a single output stream. I don’t know if this is possible, or even if it is implemented within the audio driver. I’ve just began to study the i2s/pcm manual chapter and the way it works is not yet clear in my mind.

Maybe Linux rock chip specialists could answer that?

Thx

Is same possible with RK3128 (8channel I2S)?