esp-hal/hil-test/tests/spi_half_duplex_read.rs

//! SPI Half Duplex Read Test
//!
//! Folowing pins are used:
//! SCLK    GPIO0
//! MISO    GPIO2
//!
//! GPIO    GPIO3
//!
//! Connect MISO (GPIO2) and GPIO (GPIO3) pins.

//% CHIPS: esp32 esp32c2 esp32c3 esp32c6 esp32h2 esp32s2 esp32s3

#![no_std]
#![no_main]

use esp_hal::{
    clock::ClockControl,
    dma::{Dma, DmaPriority, DmaRxBuf},
    dma_buffers,
    gpio::{GpioPin, Io, Level, Output},
    peripherals::{Peripherals, SPI2},
    prelude::*,
    spi::{
        master::{dma::SpiDma, Address, Command, Spi},
        HalfDuplexMode,
        SpiDataMode,
        SpiMode,
    },
    system::SystemControl,
    Blocking,
};
use hil_test as _;

cfg_if::cfg_if! {
    if #[cfg(any(
        feature = "esp32",
        feature = "esp32s2",
    ))] {
        use esp_hal::dma::Spi2DmaChannel as DmaChannel0;
    } else {
        use esp_hal::dma::DmaChannel0;
    }
}

struct Context {
    spi: SpiDma<'static, SPI2, DmaChannel0, HalfDuplexMode, Blocking>,
    miso_mirror: Output<'static, GpioPin<3>>,
}

#[cfg(test)]
#[embedded_test::tests]
mod tests {
    use defmt::assert_eq;

    use super::*;

    #[init]
    fn init() -> Context {
        let peripherals = Peripherals::take();
        let system = SystemControl::new(peripherals.SYSTEM);
        let clocks = ClockControl::boot_defaults(system.clock_control).freeze();

        let io = Io::new(peripherals.GPIO, peripherals.IO_MUX);
        let sclk = io.pins.gpio0;
        let miso = io.pins.gpio2;

        let miso_mirror = Output::new(io.pins.gpio3, Level::High);

        let dma = Dma::new(peripherals.DMA);

        cfg_if::cfg_if! {
            if #[cfg(any(feature = "esp32", feature = "esp32s2"))] {
                let dma_channel = dma.spi2channel;
            } else {
                let dma_channel = dma.channel0;
            }
        }

        let spi = Spi::new_half_duplex(peripherals.SPI2, 100.kHz(), SpiMode::Mode0, &clocks)
            .with_sck(sclk)
            .with_miso(miso)
            .with_dma(dma_channel.configure(false, DmaPriority::Priority0));

        Context { spi, miso_mirror }
    }

    #[test]
    #[timeout(3)]
    fn test_spi_reads_correctly_from_gpio_pin(mut ctx: Context) {
        const DMA_BUFFER_SIZE: usize = 4;

        let (buffer, descriptors, _, _) = dma_buffers!(DMA_BUFFER_SIZE, 0);
        let mut dma_rx_buf = DmaRxBuf::new(descriptors, buffer).unwrap();

        // SPI should read '0's from the MISO pin
        ctx.miso_mirror.set_low();

        let mut spi = ctx.spi;

        let transfer = spi
            .read(
                SpiDataMode::Single,
                Command::None,
                Address::None,
                0,
                dma_rx_buf,
            )
            .map_err(|e| e.0)
            .unwrap();
        (spi, dma_rx_buf) = transfer.wait();

        assert_eq!(dma_rx_buf.as_slice(), &[0x00; DMA_BUFFER_SIZE]);

        // SPI should read '1's from the MISO pin
        ctx.miso_mirror.set_high();

        let transfer = spi
            .read(
                SpiDataMode::Single,
                Command::None,
                Address::None,
                0,
                dma_rx_buf,
            )
            .map_err(|e| e.0)
            .unwrap();

        (_, dma_rx_buf) = transfer.wait();

        assert_eq!(dma_rx_buf.as_slice(), &[0xFF; DMA_BUFFER_SIZE]);
    }
}