ESP32C3 spi_read_async always returns ENOTSUP

[jkorenj]

Hello,

I am trying to implement SPI communication on ESP32C3 development boards .
I managed to implement SPI communication in blocking mode, but I need it to be implemented in async mode because I have quite a lot of data to be send.

This is my overlay file:

/ {
	chosen {
		zephyr,bt-c2h-uart = &uart1;
		zephyr,stm32-spi-telemetry = &spi2;
	};

	buttons {
		compatible = "gpio-keys";
		dry: dry_0 {
			gpios = <&gpio0 18 (GPIO_PULL_DOWN | GPIO_ACTIVE_HIGH)>;
			label = "STM RDY";
		};	
	};

	leds {
		compatible = "gpio-leds";
		drq: drq_0 {
			gpios = <&gpio0 19 GPIO_ACTIVE_HIGH>;
		};

		cs: cs_0 {
			gpios = <&gpio0 8 GPIO_ACTIVE_HIGH>;
		};
	};

};

&pinctrl {

	uart1_default: uart1_default {
		group1 {
			pinmux = <UART1_TX_GPIO7>,
				 <UART1_RX_GPIO6>,
				 <UART1_RTS_GPIO4>;
		};
		group2 {
			pinmux = <UART1_CTS_GPIO5>;
			bias-pull-up;
		};
	};

	spim2_default: spim2_default {
		group1 {
			pinmux = <SPIM2_CSEL_GPIO0>,
					 <SPIM2_SCLK_GPIO1>,
					 <SPIM2_MOSI_GPIO3>,	
					 <SPIM2_MISO_GPIO2>;			 
		};
	};

};



&uart1 {
	status = "okay";
	current-speed = <115200>;
	pinctrl-0 = <&uart1_default>;
	pinctrl-names = "default";
	hw-flow-control;
};

&spi2 {
	status = "okay";
	clock-frequency = <100000>;
	pinctrl-0 = <&spim2_default>;
	/delete-property/ half-duplex;
	dma-enabled;
};

&wifi {
	status = "okay";
};

&gpio0 {
	status = "okay";
};

I've created a new thread
This is my spi configuration

static const struct spi_buf tx_buf = {
    .buf = tx_data,
    .len = 4,
    };

    static const struct spi_buf_set tx_array_buf = {
        .buffers = &tx_buf,
        .count = 1,
    };

    static const struct spi_buf rx_buf = {  
        .buf = rx_data,
        .len = 5,
    };

    static const struct spi_buf_set rx_array_buf = {
        .buffers = &rx_buf,
        .count = 1,
    };

    static const struct spi_config spi_cfg = {
        .frequency = 100000,         // SPI frequency in Hz
        .operation = SPI_WORD_SET(8) | SPI_TRANSFER_MSB | SPI_OP_MODE_MASTER | SPI_FULL_DUPLEX,
        .slave = 0,                  // Slave number, if the SPI controller supports multiple slaves
        .cs = NULL,                  // Pointer to the CS config, if using a GPIO driven CS
        // For GPIO driven CS, specify the GPIO in a spi_cs_control struct
    };

Everything works if I call

int err = spi_read(spi_telemetry_comm, &spi_cfg, &rx_array_buf);

but when I change it to

int err = spi_read_async(spi_telemetry_comm, &spi_cfg, &rx_array_buf, &sig);

ENOTSUP error is returned.
I tried to enable SPI LOG but I received nothing that would point me to this problem.

Thank you.