i.MX6 SPI Slave mode

[stevekwon]

I'm wanting to use the SPI in slave mode (as a platform_device) in Linux 3.0.35.  Is this possible?  I've set the SPI registers (slave mode, CPOL/CPHA etc) but I don't seem to be getting anything in ECSPIx_RXDATA register when the master on the other side is sending data.  I've checked the SPI lines and it seems valid.

Here are my SPI register values:

ECSPI2_CONREG	= 0x01f00001
ECSPI2_CONFREG	= 0x00000000
ECSPI2_INTREG	= 0x00000024
ECSPI2_DMAREG	= 0x00010001
ECSPI2_STATREG	= 0x00000003

Is there anything obviously wrong in the register values or do I need to set registers other than the SPI specific registers to make it work?

[cheersalam]

Steve

If you set burst length as 32 then you will get second word as zeros. And it happens again after 128 words.

I played with all the registers and the results are all same. ss_ctl is not supported in slave mode. this issue is something deeper.

I am still trying to find a solution for it.

If you find something interesting please update us.

Alam

[cheersalam · Accepted solution]

You are not setting Chip Select signal polarity. Set the value of SS_POL as 1 (Active high) on ECSPIx_CONFIGREG register for slave mode.

[sebimohan]

Hi Mohammad Alam

   I am writing a custom driver to enable spi slave in i.MX6 using DMA.  Do we need to enable any type of clock configuration or clock form i.MX6 side for spi slave to work?

Thanks

Sebi

[robert99]

Hello Sebi,

I'm just curious about your success writing an i.MX6 SPI Slave driver supporting DMA? Can you give me a brief conclusion about your experiences?

Thank's a lot,

Robert

[peterw]

Hi Seb,

I also started with a custom SPI driver using the DMA. Can you share your SPI slave configurations?

Thanks

Peter

[robert99]

Hello Peter,

I'm just curious about your success writing an i.MX6 SPI Slave driver supporting DMA? Can you give me a brief conclusion about your experiences?

Thank's a lot,

Robert

[kiruthikavarada]

Hi Steve,

  Can you share your custom SPI slave driver using DMA on IMX6

  My email is kiruthikanv@gmail.com

Thanks,

Kiruthika

[robert99]

Hello Kiruthika,

I'm just curious about your success writing an i.MX6 SPI Slave driver supporting DMA? Can you give me a brief conclusion about your experiences?

Thank's a lot,

Robert

[YixingKong]

Steve, please click Correct Answer/Helpful Answer if your question had been answered.

Thanks,

Yixing

[fushi_peng]

Is the BURST_LENGTH data had received from bus ?

Did  you fixed TX_FIFO before receive data ?

Can you check the  interrupt  of RFEN RDREN RREN  , is these  triggered?