i.MX8mm EVK ESPI2 CS0 is always occupied on L5.15.71_2.2.0

[yao_feng]

Porting NRC7394 802.11ah device on ESPI2

skip all other spi device in device tree DTS file

My settings: based on imx8mm-evk.dtsi
https://github.com/nxp-imx/linux-imx/blob/lf-5.15.y/arch/arm64/boot/dts/freescale/imx8mm-evk.dtsi

modification:

/*skip default one

&ecspi2 {

#address-cells = <1>;

#size-cells = <0>;

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

pinctrl-names = "default";

pinctrl-0 = <&pinctrl_ecspi2 &pinctrl_ecspi2_cs>;

cs-gpios = <&gpio5 13 GPIO_ACTIVE_LOW>;

status = "okay";

spidev0: spi@0 {

reg = <0>;

compatible = "rohm,dh2228fv";

spi-max-frequency = <500000>;

};

};

*/

//add for nrc7394

&ecspi2 {

        #address-cells = <1>;

        #size-cells = <0>;

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

        pinctrl-names = "default";

        //pinctrl-0 = <&pinctrl_nrc_spi &pinctrl_ecspi2_cs>;

        pinctrl-0 = <&pinctrl_nrc_spi>;

        cs-gpios = <&gpio5 13 GPIO_ACTIVE_LOW>;

        status = "okay";

        nrc: nrc-cspi@0 {

                reg = <0>;

                compatible = "nrc80211";

                spi-max-frequency = <20000000>;

                interrupt-parent = <&gpio5>;

                interrupts = <9 8>;

        };

};

...

/*skip

pinctrl_ecspi2: ecspi2grp {

fsl,pins = <

MX8MM_IOMUXC_ECSPI2_SCLK_ECSPI2_SCLK 0x82

MX8MM_IOMUXC_ECSPI2_MOSI_ECSPI2_MOSI 0x82

MX8MM_IOMUXC_ECSPI2_MISO_ECSPI2_MISO 0x82

>;

};

*/

//add for nrc7394

        pinctrl_nrc_spi: nrcspigrp {

                fsl,pins = <

                        MX8MM_IOMUXC_ECSPI2_SCLK_ECSPI2_SCLK            0x82

                        MX8MM_IOMUXC_ECSPI2_MOSI_ECSPI2_MOSI            0x82

                        MX8MM_IOMUXC_ECSPI2_MISO_ECSPI2_MISO            0x82

                        //MX8MM_IOMUXC_ECSPI1_SS0_GPIO5_IO9               0x19

                >;

        };

But after insmod nrc.ko, I always get: Chip select 0 is occupied 

[   20.944333] nrc: loading out-of-tree module taints kernel.
[   20.954075] spi_imx 30830000.spi: chipselect 0 already in use
[   20.960032] spi_master spi1: Failed to instantiate a new spi device.
[   20.966510] nrc80211 spi1.0: [Error] gpio_reqeust() is failed (5)
[   20.972655] nrc80211 spi1.0: Failed to nrc_cspi_gpio_alloc
[   20.978185] nrc80211: probe of spi1.0 failed with error -22

I can see spi1.0 device is only the nrc one and there is no other spix.x in spi_master
cat /sys/class/spi_master/spi1/spi1.0/modalias
spi:nrc80211

I also try prebuild image LF_v6.1.55-2.2.0, there is no this issue with same DTS settings.
want to know if its the kernel 5.15 known issue?

Thanks.

[pengyong_zhang]

Hi @yao_feng 

Please make sure GPIO05_IO13 has not been Reuse  besides ecspi2 CS single in kernel 5.15.

B.R

[pengyong_zhang]

Hi @yao_feng 

Please do not comment out this line of code.

//pinctrl-0 = <&pinctrl_nrc_spi &pinctrl_ecspi2_cs>;

B.R

[yao_feng]

Hi NXP

Thanks for supporting

both settings I have tried

pinctrl-0 = <&pinctrl_nrc_spi>;
or
pinctrl-0 = <&pinctrl_nrc_spi &pinctrl_ecspi2_cs>;

Both are failed on kernel 5.15

but works on Kernel 6.1, 6.6
attached works log (kernel 6.6)

[pengyong_zhang]

Hi @yao_feng 

Following the log, it's the GPIO pin occupied. You also should configure the CS at pinctrl-0. If convenience, please share your dts file. not the part of spi setting code.

B.R

B.R

[yao_feng]

attached

[pengyong_zhang]

Hi @yao_feng 

Please share your full .dts file. cause i can not find the SPI CS setting in your dts code.

B.R

[yao_feng]

this 2 lines:

&ecspi2 {
#address-cells = <1>;
#size-cells = <0>;
fsl,spi-num-chipselects = <1>;
pinctrl-names = "default";
//pinctrl-0 = <&pinctrl_nrc_spi &pinctrl_ecspi2_cs>;
pinctrl-0 = <&pinctrl_nrc_spi>;
cs-gpios = <&gpio5 13 GPIO_ACTIVE_LOW>;
status = "okay";

nrc: nrc-cspi@0 {
reg = <0>;
compatible = "nrc80211";
spi-max-frequency = <20000000>;
interrupt-parent = <&gpio5>;
interrupts = <9 8>;
};
};