Linux/TDA2E: why Mcspi Register value has reseted after write value?

anand kumar3

Intellectual 260 points

Part Number: TDA2E

Tool/software: Linux

Hi,

I am writing SPI Slave device driver, which make McSPI 1 controller as Slave device.

For this, I configured McSPI register, writing value to MCSPI_MODULCTRL register for configure as Slave.

But, value is not set in register and also verify with reading back value from this register.

This activity, I tried with another register also but same result: NOT ABLE TO WRITE VALUE TO Register.

I gone through Data sheet also but didnot get any good pointers to solve this issue.

SOC: TDA2Ex

SPI- MCSPI1

Is any register, which i have to write first or any protocol?

if you have any pointer/document/suggestion to solve this issue, Please share it.

Thanks,

Anand Kumar

over 6 years ago

0 Shravan Karthik over 6 years ago

TI__Genius 14650 points

Hi Anand,

Couple of questions:

1. Where is the intended to run from? Linux or TI-RTOS?
2. If Linux, where are you making the modifications? Is the device enabled from the device tree?

SPI driver in slave mode isn't supported on Processor-SDK Linux.

Regards
Shravan

0 anand kumar3 over 6 years ago in reply to Shravan Karthik

Intellectual 260 points

Hi Shravan,

1.run from linux only.

2. i added driver as module in kernel and also enable from device tree.

Yes, SPI driver in slave mode is not available in linux kernel.

Therefore, i added driver for slave mode in kernel.

but problem is that it is not able to write on spi register.

Is any clock/register need to enable before writing SPI register.

Thanks,

Anand Kumar

0 anand kumar3 over 6 years ago in reply to anand kumar3

Intellectual 260 points

Hi Shravan,

Now, i am trying to configure McSPI1 to master.
Here, SPI driver in Master mode is supported in kernel.

I enable the driver and device tree node.
Clock is generated, able to see on CRO
but, CS line always at high state.

CS no-0
Vision SDK:03_04
SOC: TDA2Ex

Please give any pointer/suggestion to solve this problem.

Is device tree need pinmux values?

Thanks,
Anand Kumar

0 Shravan Karthik over 6 years ago in reply to anand kumar3

TI__Genius 14650 points

Hi Anand,

If you're able to notice the clock being generated but CS is always high, it is a pin-mux issue.
The pin-mux is set-up in u-boot (and not in kernel) and you would need to check your pinmux configuration here (board/ti/dra7xx/mux_data.h).

Regards
Shravan

0 anand kumar3 over 6 years ago in reply to Shravan Karthik

Intellectual 260 points

Thanks Shravan.

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Linux/TDA2E: why Mcspi Register value has reseted after write value?