Not able to read from spi imx6ul evk

[pratyushtomar]

I am using a wifi device on spi 4. I am able to compile drivers successfully. By debugging driver and using oscilloscope I am able to observe that driver sends packet to wifi module and wifi also replies back but at imx6 ul evk spi end no data is received. I am using spi 4 on imx6ul evk and I am using following dts configuration

&ecspi4 {

         fsl,spi-num-chipselects = <1>;

         pinctrl-names = "default";

         pinctrl-0 = <&pinctrl_ecspi4>;

         status = "okay";

        wilc_spi@0 {

             compatible = "atmel,wilc_spi";

             spi-max-frequency = <6000000>;

             reg = <0>;

             status = "okay";

        };

};

pinctrl_ecspi4: ecspi4grp {

       fsl,pins = <

                  MX6UL_PAD_ENET2_TX_CLK__ECSPI4_MISO   0x100b1

                  MX6UL_PAD_ENET2_TX_EN__ECSPI4_MOSI    0x100b1

                  MX6UL_PAD_ENET2_TX_DATA1__ECSPI4_SCLK 0x100b1

       >;

  };

[pratyushtomar]

In my case problem was with wifi module connected to spi on board and thus imxul evk board spi was working fine.

[igorpadykov · Accepted solution]

Hi Pratyush

one can test if it is working with loopback and check if spi input signal is used

in uboot/linux as part of enet2 (fec2):

pinctrl_enet2..

MX6UL_PAD_ENET2_TX_CLK__ENET2_REF_CLK2

also as ENET2_TX_CLK could be driven with reference clock, it makes

sense to check GPR1[ENET2_CLK_SEL]

Best regards

igor

-----------------------------------------------------------------------------------------------------------------------

Note: If this post answers your question, please click the Correct Answer button. Thank you!

-----------------------------------------------------------------------------------------------------------------------

[vfilip]

Hi,

were you able to get the MISO line working on ECSPI4? Seems I have similar problem. The connected device is responding correctly on incoming command but when connected to the board via Arduino header the signal I get is only edge ~2V.

I have also populated R1724, R1725, R1756, R1727 and removed R1633 (near to sd slot), R1634, R1635, R1636 (bottom).

When the signal is routed directly to the MCu, SPI works. Seems like a board issue.

best regards

Vojtech Filip

[vfilip]

Hi,

on new board revision C is necessary also to remove C416 capacitor on CPU board to get the ECSPI4 communication working.

best rgeards

Vojtech Filip