Devicetree for many peripherals (UART, I2C, SPI)

Question

I have a custom board based on the nRF5340. I have 3 UART, 2 SPI, and 4 I2C busses (9 total).

I've tried to put these in my devicetree like so:

&uart0 {
	status = "okay";
	current-speed = <115200>;
	pinctrl-0 = <&uart0_default>;
	pinctrl-1 = <&uart0_sleep>;
	pinctrl-names = "default", "sleep";
};
&uart1 {
	status = "okay";
	current-speed = <115200>;
	pinctrl-0 = <&uart1_default>;
	pinctrl-1 = <&uart1_sleep>;
	pinctrl-names = "default", "sleep";
};
&uart2 {
	status = "okay";
	current-speed = <115200>;
	pinctrl-0 = <&uart2_default>;
	pinctrl-1 = <&uart2_sleep>;
	pinctrl-names = "default", "sleep";
};

&i2c3 {
	compatible = "nordic,nrf-twim";
	status = "okay";
	clock-frequency = <I2C_BITRATE_FAST>;
	pinctrl-0 = <&i2c3_default>;
	pinctrl-1 = <&i2c3_sleep>;
	pinctrl-names = "default", "sleep";
};

&i2c4 {
	compatible = "nordic,nrf-twim";
	status = "okay";
	clock-frequency = <I2C_BITRATE_FAST>;
	pinctrl-0 = <&i2c4_default>;
	pinctrl-1 = <&i2c4_sleep>;
	pinctrl-names = "default", "sleep";
};

&i2c6 {
	compatible = "nordic,nrf-twim";
	status = "okay";
	clock-frequency = <I2C_BITRATE_FAST>;
	pinctrl-0 = <&i2c6_default>;
	pinctrl-1 = <&i2c6_sleep>;
	pinctrl-names = "default", "sleep";
};

&i2c7 {
	compatible = "nordic,nrf-twim";
	status = "okay";
	clock-frequency = <I2C_BITRATE_FAST>;
	pinctrl-0 = <&i2c7_default>;
	pinctrl-1 = <&i2c7_sleep>;
	pinctrl-names = "default", "sleep";
};

&spi8 {
	compatible = "nordic,nrf-spim";
	status = "okay";
	cs-gpios = <&gpio0 11 GPIO_ACTIVE_LOW>, // Thermistors
	<&gpio0 31 GPIO_ACTIVE_LOW>, // Empty
	<&gpio0 4 GPIO_ACTIVE_LOW>,  // TEC DAC
	<&gpio0 5 GPIO_ACTIVE_LOW>; // Empty

	pinctrl-0 = <&spi8_default>;
	pinctrl-1 = <&spi8_sleep>;
	pinctrl-names = "default", "sleep";
};

&spi9 {
	compatible = "nordic,nrf-spim";
	status = "okay";
	cs-gpios = <&gpio0 19 GPIO_ACTIVE_LOW>, // Ethernet
	<&gpio0 12 GPIO_ACTIVE_LOW>; // Empty

	pinctrl-0 = <&spi9_default>;
	pinctrl-1 = <&spi9_sleep>;
	pinctrl-names = "default", "sleep";
};

This throws an error that "i2c4" is an "unknown label", because it's not defined in `nrf5340_cpuapp_peripherals.dtsi`.

I can't double up on the peripheral indexes (e.g. `uart0` and `i2c0`), because they both share the same address in `nrf5340_cpuapp_peripherals.dtsi` and it throws an error saying "only one of the following peripherals can be enabled...".

Is there a way to define more then 4 UART/I2C/SPI peripherals on an nRF5340?

Naeem Maroof · Accepted Answer

Number of peripherals and IDs are as defined in the product specification, so you can not add more. 
 But as for the serial bus (I2C and SPI) is concerned, what you can do is put multiple devices on single bus and address them as per your use case.

Devicetree for many peripherals (UART, I2C, SPI)

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