topic IMX8MP ECSPI3 MISO Problem in i.MX Processors

IMX8MP ECSPI3 MISO Problem

AlfTeleco — Wed, 22 Sep 2021 08:27:57 GMT

Hello,

We are having some problems using ECSPI3 at an imx8mp custom board.

Mosi, SCLK and CS seems to be working okay, but MISO is no even working in loopback mode.

Any idea? Is there any kernel problem or special configuration at dts?

Thanks a lot!

Re: IMX8MP ECSPI3 MISO Problem

igorpadykov — Wed, 22 Sep 2021 10:29:08 GMT

Hi Alvaro

what bsp used in the case. May be recommended to try latest Linux 5.10.35_2.0.0

https://source.codeaurora.org/external/imx/linux-imx/tree/?h=lf-5.10.y

with unit test

https://source.codeaurora.org/external/imx/imx-test/tree/test/mxc_spi_test?h=lf-5.10.y_2.0.0

Best regards
igor

Re: IMX8MP ECSPI3 MISO Problem

AlfTeleco — Wed, 22 Sep 2021 13:52:59 GMT

Hi Igor and thanks for the quick answer.

We are using imx kernel 5.4.70. The problem seems to be related to CS signal. CS seems to be going inactive between writes and reads, maybe making the slave become unavailable. The problem is shown in this picture:

Any idea will be much appreciated, thank you