It's been nearly one year since I requested, both in their forum and here but still no solution. Other vendor like CompuLab here have a solution to change their dts to support spidev, but not SolidRun.
Checking from their dts even in the latest sr-imx8-debian-bullseye-20191201-cli-imx8mq-sdh.. image, it seems like all ecspi0,1,2 are still disabled. The HBPulse has a mikroBus interface that uses ecspi2, so this is the bus that I would like to enable. I tried changing to status to 'okay', but apparently I need to also add another node to the dts with the following entry. I'm not sure what to fill in the pinctrl-0, cs-gpios, and reg fields? Perhaps someone can look at the HbPulse schematic that I attached and provide me the info?
&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 = "epson,s1d13c00";
spi-max-frequency = <500000>;
};
};
After some readings about dtb in general this is the modified:
ecspi@30830000 {
#address-cells = <0x01>;
#size-cells = <0x00>;
compatible = "spidev,fsl,imx8mq-ecspi\0fsl,imx51-ecspi";
reg = <0x00 0x30830000 0x00 0x10000>;
interrupts = <0x00 0x20 0x04>;
clocks = <0x04 0xc2 0x04 0xc2>;
clock-names = "ipg\0per";
status = "okay";
fsl,spi-num-chipselects = <1>;
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_ecspi2 &pinctrl_ecspi2_cs>;
cs-gpios = <&gpio5 13 GPIO_ACTIVE_LOW>;
spidev0: spi@0 {
reg = <0>;
compatible = "spidev";
spi-max-frequency = <500000>;
status = "okay";
};
The pinctrl that handles io muxing is very complex and I'm still yet to know what to define, there is no pinctrl_ecspi2 defined anywhere in the dts.
Useful reference regarding imx8 to help modify the dts:
pinfunc - linux/imx8mq-pinfunc.h at master · torvalds/linux · GitHub
Device Tree Customization
linux/arch/arm64/boot/dts/freescale at master · torvalds/linux · GitHub
https://www.nxp.com/docs/en/user-guide/i.MX_BSP_Porting_Guide_Linux.pdf (pg.31-32)
Serial Peripheral Interface (SPI)
Really wish these could be enabled by default.
