SPI Neopixel required Clock

[Shahin97]

hello, 

I have a neo pixel running on my nrf52840 using SPI. I still require the SPI clock pin to be configured to a pin even though it is unused. This wastes a pin, is there a way round this? 

Here is my DTS

&spi2 { /* MOSI on P0.17 */
	pinctrl-0 = <&spi2_alt>;
	pinctrl-1 = <&spi2_sleep_alt>;
	pinctrl-names = "default", "sleep";
	status = "okay";
	led_strip: ws2812@0 {
		compatible = "worldsemi,ws2812-spi";

		/* SPI */
		reg = <0>; /* ignored, but necessary for SPI bindings */
		spi-max-frequency = <4000000>;

		/* WS2812 */
		chain-length = <1>; /* arbitrary; change at will */
		color-mapping = < LED_COLOR_ID_GREEN
						  LED_COLOR_ID_RED
						  LED_COLOR_ID_BLUE >;
		spi-one-frame = <0x70>;
		spi-zero-frame = <0x40>;
		power-domains = <&domain_5v_sw>;
		supply-gpios = <&gpio0 20 GPIO_ACTIVE_HIGH>;
	};
};

[Turbo J]

Nopers. The SPIM refuses to work when it can't clock out the SCK signal.

Probably a good idea to write a driver for the ws2812 LED stuff that actually uses the PWM peripherial properly, but I don't see one yet. If you really needed to save that one pin, that would be your task to do here...

[Shahin97]

I don't need the pin, it was more of an optimization. I do like contributing to zephyr so might be a fun side quest when I'm free,  I may look into the PWM peripheral for this.