How to add ssi in TDM (network) mode to device tree imx6

[jesseforgues]

How to add ssi in TDM (network) mode to device tree imx6

Since the above issue was answered I was curious of anyone had a Device Tree example of using the SSI in TDM (network) mode.

I am trying to use 2 or 3 SSIs to do 8 channels of TDM on each (due to 8ch TDM codec limitations/ AK5388).

[alejandrolozan1]

Hi,

The iMX6 Sabre Auto platforms supports CS42800 which has a 8 channel playback capability. CS42888 codec uses ESAI interface, and the driver enabled TDM.

It is worth taking a look at it. In the above link Fabio provided the answer, FabioEstevam​, do you have something that can help Jesse?

Best Regards,

/Alejandro

[fabio_estevam]

Current SSI driver only supports up to two channels. ESAI driver supports multichannel.

Regards,

Fabio Estevam

[josbijma]

Hi,

Are there any developments going on to support mulichannel with SSI? We need 4 channel support with SSI interface and cannot use ESAI due to pinout.

Or could you give some pointers what we need to do to develop multichannel support in the SSI-driver?

[fabio_estevam]

Hi Jos,

I am not aware of any current activities in this area.

I would suggest to trying to understand from a register level what are the required configurations to get this mode working and then implement it in the ssi driver.

Unfortunately I don't have any hardware that can support such mode here.

Regards,

Fabio Estevam

[jesseforgues]

I see, can you clarify a few things. So the current SSI driver only supports 2 channels.

Wasn't multichannel TDM supported in the SSI driver at one point prior to 3.10? (prior to device tree)

According to the ref manual the hardware can support it but the software support is no longer present?

Is this correct?

[fabio_estevam]

Hi Jesse,

Just looked at the 3.0 driver and it also does not support multichannel.

Regards,

Fabio Estevam

[jesseforgues]

And just to share why, I am already using the ESAI port for another codec.

[alejandrolozan1]

Thanks Fabio!!