How to add spi node in "/dev"

[JunpapaCS]

Hello?

Based on imx8mm-evk board, I'm trying to control IC  with connecting through ecspi2 ports of "EXP CN"  attached.
After adding some codes imx8mm-evk.dts like the below, updated imx8mm-evk.dtb on boot disc, but there's no any "spi device" on directory, "/dev".

Could anyone help to resolve this?

&ecspi2 {
#address-cells = <1>;
#size-cells = <0>;
fsl,spi-num-chipselects = <1>;
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_ecspi2>;
cs-gpios = <&gpio5 13 GPIO_ACTIVE_LOW>;
status = "okay";

spidev1: spi@0 {
reg = <0>;
compatible = "rohm,dh2228fv";
spi-max-frequency = <500000>;
};
};

pinctrl_ecspi2: ecspi2grp {
fsl,pins = <
MX8MM_IOMUXC_ECSPI2_SCLK_ECSPI2_SCLK 0x19 //0x11
MX8MM_IOMUXC_ECSPI2_MOSI_ECSPI2_MOSI 0x19 //0x11
MX8MM_IOMUXC_ECSPI2_MISO_ECSPI2_MISO 0x19 //0x11
>;
};

[JunpapaCS]

Hi 

I got the result of the below.

SPI stack is alive but not working. 

SW: rel_imx_5.4.47_2.2.0

HW: imx8mm EVK Board,

The below is Imx8mm-evk.dts

&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";

spidev@0 {

reg = <0>;

compatible = "spidev";

spi-max-frequency = <500000>;     //<100000>;

};

};

pinctrl_ecspi2: ecspi2grp {

fsl,pins = <

MX8MM_IOMUXC_ECSPI2_SCLK_ECSPI2_SCLK               0x82  //0x175 //0x00001916 //0x11

MX8MM_IOMUXC_ECSPI2_MOSI_ECSPI2_MOSI             0x82  //0x175 //00000116  //0x11

MX8MM_IOMUXC_ECSPI2_MISO_ECSPI2_MISO             0x82  //0x175 // 00000116  //0x1

>;

};

pinctrl_ecspi2_cs: ecspi2cs {

fsl,pins = <

MX8MM_IOMUXC_ECSPI2_SS0_GPIO5_IO13       0x40000

>;

}

• Spi node : created “spidev1.0” in “/dev”  folder

• Loopback : Connect SDI & SDO directly , pin 19 & 21 of EXP CN(attached)

• Refet to EXP CN Page 13, “SPF-31407_C2 EVK-BASE Board Circuit .pdf”

• Test : $  ./spidev_test -v -D /dev/spidev1.0  (the result is attached)
• The value of CLK, DSO, & SS ports never changed.

root@imx8mmevk:/run/media/mmcblk1p3# ./spidev_test -v -D /dev/spidev1.0
spi mode: 0x0
bits per word: 8
max speed: 500000 Hz (500 KHz)
TX | FF FF FF FF FF FF 40 00 00 00 00 95 FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF F0 0D |......@.........................|
RX | 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................................|

Refer to result “dmesg | grep spi”

root@imx8mmevk:/run/media/mmcblk1p3# dmesg | grep spi
[ 1.354391] spi_imx 30830000.spi: registered master spi1
[ 1.354503] spi spi1.0: spi_imx_setup: mode 1, 8 bpw, 1000000 hz
[ 1.354512] spi spi1.0: setup mode 1, 8 bits/w, 1000000 Hz max --> 0
[ 1.354772] spi_imx 30830000.spi: registered child spi1.0
[ 1.354778] spi_imx 30830000.spi: probed
[ 1.359164] imx8mm-pinctrl 30330000.pinctrl: pin MX8MM_IOMUXC_NAND_ALE already requested by 30830000.spi; cannot claim for 30bb0000.spi
[ 1.371350] imx8mm-pinctrl 30330000.pinctrl: pin-61 (30bb0000.spi) status -22
[ 1.378498] imx8mm-pinctrl 30330000.pinctrl: could not request pin 61 (MX8MM_IOMUXC_NAND_ALE) from group flexspi0grp on device 30330000.pinctrl
[ 1.391459] nxp-fspi 30bb0000.spi: Error applying setting, reverse things back
[ 1.398697] nxp-fspi: probe of 30bb0000.spi failed with error -22
[ 51.841387] spidev spi1.0: spi_imx_setup: mode 0, 8 bpw, 1000000 hz
[ 51.841399] spidev spi1.0: setup mode 0, 8 bits/w, 1000000 Hz max --> 0
[ 51.841403] spidev spi1.0: spi mode 0
[ 51.841413] spidev spi1.0: spi_imx_setup: mode 0, 8 bpw, 1000000 hz
[ 51.841423] spidev spi1.0: setup mode 0, 8 bits/w, 1000000 Hz max --> 0
[ 51.841426] spidev spi1.0: 8 bits per word
[ 51.841436] spidev spi1.0: spi_imx_setup: mode 0, 8 bpw, 500000 hz
[ 51.841442] spidev spi1.0: setup mode 0, 8 bits/w, 500000 Hz max --> 0
[ 51.841699] spi_imx 30830000.spi: mx51_ecspi_clkdiv: fin: 50000000, fspi: 500000, post: 3, pre: 12
[ 75.901686] spidev spi1.0: spi_imx_setup: mode 0, 8 bpw, 1000000 hz
[ 75.901699] spidev spi1.0: setup mode 0, 8 bits/w, 1000000 Hz max --> 0
[ 75.901704] spidev spi1.0: spi mode 0
[ 75.901713] spidev spi1.0: spi_imx_setup: mode 0, 8 bpw, 1000000 hz
[ 75.901722] spidev spi1.0: setup mode 0, 8 bits/w, 1000000 Hz max --> 0
[ 75.901726] spidev spi1.0: 8 bits per word
[ 75.901735] spidev spi1.0: spi_imx_setup: mode 0, 8 bpw, 500000 hz
[ 75.901741] spidev spi1.0: setup mode 0, 8 bits/w, 500000 Hz max --> 0
[ 75.902104] spi_imx 30830000.spi: mx51_ecspi_clkdiv: fin: 50000000, fspi: 500000, post: 3, pre: 12
[ 149

[JunpapaCS]

I got..

"The last integer CONFIG is the pad setting value like pull-up on this pin. Please refer to i.MX8M Mini Reference Manual for detailed CONFIG settings."

"8.2.5.279 Pad Control Register"
(IOMUXC_SW_PAD_CTL_PAD_ECSPI2_SCLK)

Thanks! 

BR

Weidong

[JunpapaCS]

Hi, Weidong

On the imx8mm-evk board for new project, I just copied a spi codes from imx7ulp.dts used in an old project.

so I'm not sure  that "dh2228fv" chip is used or not in the EVK board. so it should be changed.  (I'm a complete novice at Linux)
I realized there's some setting issues in imx8mm-evk.dts through "dmesg | grep spi" and "booting messages",  so I'm trying to find a solution through reading related documents and manual.

I don't know what "xxxx" means in the below codes.
(??  initial values or setting values in a register )

Could you let me give any reference related about the usage ?

Thank you in advance.

------------------
pinctrl_ecspi2: ecspi2grp {
fsl,pins = <
MX8MM_IOMUXC_ECSPI2_SCLK_ECSPI2_SCLK  "xxxx"
MX8MM_IOMUXC_ECSPI2_MOSI_ECSPI2_MOSI  "xxxx"
MX8MM_IOMUXC_ECSPI2_MISO_ECSPI2_MISO  "xxxx"
MX8MM_IOMUXC_ECSPI2_SS0_ECSPI2_SS0       "xxxx"
>;
};

[weidong_sun · Accepted solution]

Hi,

You can refer to imx8mn-evk.dts.

See below, please!

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
>;
};

pinctrl_ecspi2_cs: ecspi2cs {
fsl,pins = <
MX8MM_IOMUXC_ECSPI2_SS0_GPIO5_IO13  0x40000
>;
};

......

&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>;
};
};

Have a nice day!

B.R,

weidong

[Dandroid4NXP]

I'm having similar issues to what is described in this forum thread. I've been spending several days trying to get the escpi2 on the imx8 work, by having the imx-spi.c and spi.c linux drivers use the chip select SS0 line configured for GPIO5_IO13. I've seen similar configuration settings used in several other NXP posts to configure the chip select (CS) for escpi2.

Can you please explain the line:

MX8MM_IOMUXC_ECSPI2_SS0_GPIO5_IO13  0x40000

The 0x40000 sets reserved bit 18.

Can you please provide a definition for bit 18 ?

Are there any other secret reserved bits that exist in this register?

Can you please update the documentation to describe these secret reserved bits ?

I also tried to use the i.MX_CFG_v12 Config Tools for i.MX Version 12 and was unable to find my answer there.

[weidong_sun]

Hi,

   1. you should confirm if dh2228fv driver is in kernel.

   2. GPIO5_13 pin should be multiplexed in device tree.

have a nice day!

B.R,

weidong