Using on esp32 with embassy hangs on Epd2in9bc::new

[JohnTheCoolingFan]

Hello, I am trying to drive an epaper display (2.9inch b/w/r from weact, analogous to waveshare module, working with GxEPD2) using this library, running on esp32 using embassy. The lack of examples really makes it difficult, but I'm trying to figure it out.
One problem is that the library doesn't allow to just use the esp_hal::spi::master::Spi and instead one has to "wrap" it through embassy_embedded_hal::blocking::spi::SpiDevice, which itself requires a lot of setup.

So, here's my code so far, based on a template from esp-generate:

#![no_std]
#![no_main]

use core::cell::RefCell;

use embassy_embedded_hal::shared_bus::blocking::spi::SpiDevice;
use embassy_executor::Spawner;
use embassy_sync::blocking_mutex::NoopMutex;
use embassy_time::{Duration, Timer};
use embedded_graphics::{
    prelude::{Point, Primitive},
    primitives::{Line, PrimitiveStyle},
    Drawable,
};
use esp_backtrace as _;
use esp_hal::{
    gpio::{Input, Level, NoPin, Output, Pull},
    prelude::*,
    spi::{
        master::{Config, Spi},
        SpiMode,
    },
    Blocking,
};
use log::info;

extern crate alloc;

use epd_waveshare::{epd2in9bc::*, prelude::*};
use static_cell::StaticCell;
#[main]
async fn main(spawner: Spawner) {
    let peripherals = esp_hal::init({
        let mut config = esp_hal::Config::default();
        config.cpu_clock = CpuClock::max();
        config
    });

    esp_alloc::heap_allocator!(72 * 1024);

    esp_println::logger::init_logger_from_env();

    let timer0 = esp_hal::timer::timg::TimerGroup::new(peripherals.TIMG1);
    esp_hal_embassy::init(timer0.timer0);

    info!("Embassy initialized!");

    /*
    let timer1 = esp_hal::timer::timg::TimerGroup::new(peripherals.TIMG0);
    let _init = esp_wifi::init(
        timer1.timer0,
        esp_hal::rng::Rng::new(peripherals.RNG),
        peripherals.RADIO_CLK,
    )
    .unwrap();
    */

    info!("Initializing spi bus");

    static SPI_BUS: StaticCell<NoopMutex<RefCell<Spi<'static, Blocking>>>> = StaticCell::new();
    let spi_bus = Spi::new(peripherals.SPI2)
        //.with_cs(peripherals.GPIO5)
        .with_cs(NoPin)
        .with_sck(peripherals.GPIO18)
        .with_mosi(peripherals.GPIO23)
        .with_miso(NoPin);
    let spi_bus = NoopMutex::new(RefCell::new(spi_bus));
    let spi_bus = SPI_BUS.init(spi_bus);

    info!("Initializing spi device");

    let mut spi = SpiDevice::new(spi_bus, Output::new(peripherals.GPIO5, Level::Low));

    info!("Initializing pins");

    let busy_in = Input::new(peripherals.GPIO4, Pull::Down);
    let dc = Output::new(peripherals.GPIO17, Level::Low);
    let rst = Output::new(peripherals.GPIO16, Level::High);

    let mut delay = embassy_time::Delay;

    info!("Initializing epd");

    let mut epd =
        Epd2in9bc::new(&mut spi, busy_in, dc, rst, &mut delay, None).expect("EPD creation error");

    info!("Drawing");

    let mut mono_display = Display2in9bc::default();

    let _ = Line::new(Point::new(0, 120), Point::new(0, 200))
        .into_styled(PrimitiveStyle::with_stroke(Color::Black, 1))
        .draw(&mut mono_display);

    let mut chromatic_display = Display2in9bc::default();

    let _ = Line::new(Point::new(15, 120), Point::new(15, 200))
        .into_styled(PrimitiveStyle::with_stroke(Color::Black, 1))
        .draw(&mut chromatic_display);

    info!("Updating color frame");

    epd.update_color_frame(
        &mut spi,
        &mut delay,
        mono_display.buffer(),
        chromatic_display.buffer(),
    )
    .unwrap();

    epd.display_frame(&mut spi, &mut delay).unwrap();

    info!("Pre sleep");

    epd.sleep(&mut spi, &mut delay).unwrap();

    info!("Post sleep");

    // TODO: Spawn some tasks
    let _ = spawner;

    loop {
        info!("Hello world!");
        Timer::after(Duration::from_secs(1)).await;
    }

    // for inspiration have a look at the examples at https://github.com/esp-rs/esp-hal/tree/v0.22.0/examples/src/bin
}

With the debug logs in place, the point in the program where it stops is after info!("Initializing epd");.
Did I do something obviously wrong in my code? What can I do to diagnose the issue further to find out why it's hung?

[JohnTheCoolingFan]

Potentially related issues, none of which have an answer:

• Fail to interact with epd3in7 display #140 faulty original code and the comment focuses on the code part that was added to test the spi and just gives a vague example with their HAL
• Epd4in2::new() waits forever #155 No answer from original author
• 7.5" V2 display driver does not work #70 old and outdated, uses a different module, code links are not permalinks so no idea what was the library code linked

[JohnTheCoolingFan]

Also, a pin mapping:

EPD	ESP32
GND	GND
VCC	3V3
SDA	P23 (VSPI MOSI)
SCL	P18 (VSPI SCLK)
CS	P5
D/C	P17
RES	P16
BUSY	P4

Same as what I've used to run GxEPD2 example

[JohnTheCoolingFan]

For info, here are the crate versions I'm using:

esp-backtrace = { version = "0.14.2", features = [
    "esp32",
    "exception-handler",
    "panic-handler",
    "println",
]}

esp-hal = { version = "0.22.0", features = [
    "esp32",
] }
esp-println = { version = "0.12.0", features = ["esp32", "log"] }
log = { version = "0.4.21" }
esp-alloc = { version = "0.5.0" }
embedded-io = "0.6.1"

embedded-io-async = "0.6.1"
embassy-net = { version = "0.4.0", features = [ "tcp", "udp", "dhcpv4", "medium-ethernet"] }

esp-wifi = { version = "0.11.0", default-features=false, features = [
    "esp32",
    "utils",
    "wifi",
    "esp-alloc",
    "log",
] }
heapless = { version = "0.8.0", default-features = false }
smoltcp = { version = "0.11.0", default-features = false, features = [
    "medium-ethernet",
    "proto-dhcpv4",
    "proto-igmp",
    "proto-ipv4",
    "socket-dhcpv4",
    "socket-icmp",
    "socket-raw",
    "socket-tcp",
    "socket-udp",
] }
embassy-executor = { version = "0.6.0",  features = [
    "task-arena-size-12288",
] }
embassy-time     = { version = "0.3.1",  features = ["generic-queue-8"] }
esp-hal-embassy  = { version = "0.5.0",  features = ["esp32"] }
static_cell      = { version = "2.1.0",  features = ["nightly"] }
critical-section = "1.2.0"
epd-waveshare = "0.6.0"
embedded-graphics = "0.8.1"
embassy-embedded-hal = "0.2.0"
embassy-sync = "0.6.1"
embedded-hal-bus = "0.2.0"

[JohnTheCoolingFan]

I've checked some things and I think this library has a problem with Epd2in9bc::new or Epd2in9bc::init specifically.

I've used https://github.com/GnomedDev/epaper-simplyplural-badge/tree/0440c798289a3b36dcfb42f4938d9fc3a9111da9 as a base project to verify whether the project that was linked to me would work if I tweak it to my hardware. I've done some incremental changes: first changing gpio pins, then adding logging, and at the end changing from epd2in13_v2 to epd2in9bc. The last one caused the program to break. Source code here: https://github.com/JohnTheCoolingFan/epaper-simplyplural-badge/tree/f58ac26fcb97d9d7a89a55d27dc0b1b0afd37201

[JohnTheCoolingFan]

Also, switching to Epd2in9 goes past new so now I am quite confident there's a bug in the implementation of epd2in9bc. I'll check whether it depends on the platform (esp32) later