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imx6 ssi in network mode

Question asked by j-g on Mar 25, 2014
Latest reply on Dec 16, 2016 by marco rosciio

Hello,

 

I am trying to configure the imx6 ssi to transmit 8 channels in network mode (TDM).  I have a DSP that is providing frame sync (one clock bit) and bit clock to the imx6 (both are confirmed working).  Frame sync is 48khz, bit clock is 6.144mhz (8 channels, 16 bits per channel)

 

SSI_SCR = 0x118  (network mode enabled, Synchronous mode selected, Two-channel mode enabled.)

SSI_STCR = 0x38F (Transmit frame sync is initiated one bit before the data is transmitted, one clock bit, active low frame sync, falling edge data, transmit FIFO 0 enabled, transmit FIFO 1 enabled, LSB Aligned)

SSI_STCCR = 0x4E700 (PM = 0, DC = 7, Word Length Control = 7, PSR = 0, DIV2 = 1)

 

In imx-ssi.c structure snd_soc_dai_driver_imx_ssi_dai I changed channels_min = 8 and channels_max = 8
In imx-pcm-dma-mx2.c structure snd_imx_hardware I changed channels_min = 8 and channels_max = 8

 

I use aplay to play a wav file, and get no data on the data line, aplay hangs.  I should add that I did have this configured as I2S Slave (2 channel) with the DSP setup appropriately and that did work.  Now that I'm trying to switch to network mode and 8 channels, I can't seem to get any data out.

 

Any advice/links/info would be greatly appreciated.

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