There is a bug in spim init in NCS SDK 3.21

[zoroada]

After initialization, pin 0 will be configured as the ss_pin by default

[Kazi Afroza Sultana]

Hello.

Can you tell a bit detail about your issue? Which application you are trying to use? What is the NCS version and SoC?

[zoroada]

Using the nRF low-level driver SPIM to drive the WS2818 lights, initializing only with the .mosi_pin pin, which is P0.17. The ss_pin is set to NRF_SPIM_PIN_NOT_CONNECTED to indicate it is not used. After initialization, as shown in Figures 1.2 above, P0.0 is used as the default ss_pin. When using nrfx_spim_uninit(&spi_ws2812), it will call this function for P0.0:

static void spim_pin_uninit(uint32_t pin)
{
if (pin == NRF_SPIM_PIN_NOT_CONNECTED ||
#if defined(SPIM_DCX_DISCONNECTED_READBACK)
pin == SPIM_DCX_DISCONNECTED_READBACK ||
#endif
0)
{
return;
}

nrfy_gpio_cfg_default(pin);
}

[zoroada]

My P0.0 pin is being used by other peripherals, so after calling nrfx_spim_uninit(&spi_ws2812), it causes issues with the other peripherals.

[zoroada]

Issue resolved. After switching from SDK 3.11 to 3.21, the original struct required the const modifier. In 3.21, const can no longer be used, and using it causes ss_pin to default to 0 and become unmodifiable.