Using NRFX SPIS in nRF Connect SDK

[Anthony]

Hello,

I'm trying to use a SPIS peripheral from the NRFX library in a nRF Connect SDK 2.7.0 project. The reason for using the NRFX library is to clear a GPIO pin in the SPI ISR when the transfer is finished.

The prj.conf contains the following options (i'm using the SPIS1 peripheral):

CONFIG_SPI=y
CONFIG_SPI_NRFX=y
CONFIG_NRFX_SPIS1=y

The device tree overlay contains the following SPI slave peripheral:

&spi1 {
    compatible = "nordic,nrf-spis";
    status = "disabled";  // tried "okay" but nrfx_spis_init returns NRFX_ERROR_ALREADY
    def-char = <0xff>;
};

I followed the code in modules/hal/nordic/nrfx/samples/src/nrfx_spim_spis/advanced_non_blocking/main.c in the NCS root directory. I didn't use the line IRQ_CONNECT(NRFX_IRQ_NUMBER_GET(NRF_SPIS_INST_GET(SPIS_INST_IDX)...) because it didn't compile. Maybe this line isn't necessary when SPI is enabled in the prj.conf file.

The SPI is initialized with nrfx_spis_init() as follows. Then the nrfx_spis_init_check() function returns true.

    nrfx_spis_config_t spis_config = {
        .miso_pin     = 38,
        .mosi_pin     = 37,
        .sck_pin      = 36,
        .csn_pin      = 35,
        .mode         = NRF_SPIS_MODE_0,
        .bit_order    = NRF_SPIS_BIT_ORDER_LSB_FIRST,
        .csn_pullup   = NRF_GPIO_PIN_NOPULL,
        .miso_drive   = NRF_GPIO_PIN_S0S1,
        .def          = 0xFF, 
        .orc          = 0xFF, 
        .irq_priority = 6, 
    };
    nrfx_err_t err = nrfx_spis_init(&spis, &spis_config, &nrfx_spis_event_handler, NULL);

The problem is that `nrfx_spis_buffers_set()` never returns:

err = nrfx_spis_buffers_set(&spis, m_tx_buf, m_tx_len, m_rx_buf, m_rx_len); // Stays blocked here

Would you have an idea of what could be the problem ?

[Turbo J]

The status property must be set to "okay". Might fix the IRQ_CONNECT() problem.

Not sure if you needed more changes in the device tree - look at the combined tree files in the build/zephyr directory.

[Anthony]

Thank you for you answer.

I tried to set the `status` field of the SPIS1 peripheral to "okay" in the device tree.
When I put the line with IRQ_CONNECT(...), the following compile error occurs:

C:/ncs/v2.7.0/zephyr/include/zephyr/arch/arm/irq.h:117:1: error: expected identifier or '(' before '{' token
  117 | { \
      | ^
C:/ncs/v2.7.0/zephyr/include/zephyr/irq.h:49:9: note: in expansion of macro 'ARCH_IRQ_CONNECT'
   49 |         ARCH_IRQ_CONNECT(irq_p, priority_p, isr_p, isr_param_p, flags_p)
   

where the IRQ_CONNECT line is as follows :

#define SPIM_INST_IDX 1

IRQ_CONNECT(NRFX_IRQ_NUMBER_GET(NRF_SPIS_INST_GET(SPIS_INST_IDX)), IRQ_PRIO_LOWEST, NRFX_SPIS_INST_HANDLER_GET(SPIS_INST_IDX), 0, 0);

If I remove the IRQ_CONNECT line, the project compiles but nrfx_spis_init() returns NRFX_ERROR_ALREADY.

I tried several other combinations. I also tried to define the SPI pin numbers in the device tree, but that didn't solve the problem :

&pinctrl {
    spis_default: spis_default {
        group1 {
            psels = <NRF_PSEL(SPIS_SCK, 1, 04)>,
                <NRF_PSEL(SPIS_MISO, 1, 06)>,
                <NRF_PSEL(SPIS_MOSI, 1, 05)>;
        };
    };
};

This is how the spis1 peripheral appears in the combined device tree in build/zephyr/zephyr.dts :

		spi1: spi@40004000 {
			compatible = "nordic,nrf-spis";
			#address-cells = < 0x1 >;
			#size-cells = < 0x0 >;
			reg = < 0x40004000 0x1000 >;
			interrupts = < 0x4 0x1 >;
			max-frequency = < 0x7a1200 >;
			easydma-maxcnt-bits = < 0x10 >;
			status = "okay";
			pinctrl-0 = < &spis_default >;
			pinctrl-1 = < &spi1_sleep >;
			pinctrl-names = "default", "sleep";
			def-char = < 0xff >;
		};

I also tried to compile the example in modules/hal/nordic/nrfx/samples/src/nrfx_spim_spis/advanced_non_blocking/ using `west build -b nrf52840dk_nrf52840`, but the compilation fails (CMake Error at CMakeLists.txt:11 GET_DEVICE_CONFIG_FILES Macro invoked with incorrect arguments).

Would you have other ideas that I can try ? I can upload the succinct source file of my project if needed.

[Turbo J]

Any reason why you try to code yourself instead of just using the existing driver in zephyr/drivers/spi/spi_nrfx_spis.c source file? It would get enabled via correct DT automagically.