ProjektMaus/src/custom_hid.rs

use crate::{serial::Serial, MouseInfoSender};

use rp_pico as bsp;

use bsp::{
    hal::{
        clocks::ClocksManager,
        pac,
        pac::{interrupt, Interrupt},
        usb::UsbBus,
    },
    pac::{RESETS, USBCTRL_DPRAM, USBCTRL_REGS},
};

use usb_device::{class_prelude::*, prelude::*};
use usbd_hid::descriptor::MouseReport;

static mut USB_BUS: Option<UsbBusAllocator<UsbBus>> = None;
static mut USB_SERIAL: Option<Serial> = None;
static mut USB_DEVICE: Option<UsbDevice<UsbBus>> = None;

pub struct CustomHID<'a> {
    out_ep: EndpointOut<'a, UsbBus>,
    in_ep: EndpointIn<'a, UsbBus>,
}

impl<'a> CustomHID<'a> {
    pub fn new(
        usbctrl_reg: USBCTRL_REGS,
        usbctrl_dpram: USBCTRL_DPRAM,
        resets: &mut RESETS,
        clocks: ClocksManager,
        poll_ms: u8,
    ) -> Self {
        // Set up the USB driver
        unsafe {
            USB_BUS = Some(UsbBusAllocator::new(UsbBus::new(
                usbctrl_reg,
                usbctrl_dpram,
                clocks.usb_clock,
                true,
                resets,
            )))
        };

        unsafe {
            USB_SERIAL = Some(Serial::new(USB_BUS.as_ref().unwrap()));
        }

        unsafe {
            USB_DEVICE = Some(
                UsbDeviceBuilder::new(USB_BUS.as_ref().unwrap(), UsbVidPid(0x16c0, 0x27dd))
                    .manufacturer("Fake company")
                    .product("Serial port")
                    .serial_number("TEST")
                    .device_class(2) // from: https://www.usb.org/defined-class-codes
                    .build(),
            );
        }

        let (in_ep, out_ep) = unsafe {
            pac::NVIC::unmask(Interrupt::USBCTRL_IRQ);

            (
                USB_BUS.as_ref().unwrap().interrupt(64, poll_ms),
                USB_BUS.as_ref().unwrap().interrupt(64, poll_ms),
            )
        };

        Self { in_ep, out_ep }
    }
}

impl<'a> MouseInfoSender for CustomHID<'a> {
    fn send(&mut self, x: i8, y: i8, buttons: u8, wheel: i8, pan: i8) {
        push_mouse_movement(MouseReport {
            x,
            y,
            buttons,
            wheel,
            pan,
        })
    }
}

/// with interrupts disabled, to avoid a race hazard with the USB IRQ.
fn push_mouse_movement(report: MouseReport) {
    critical_section::with(|_| unsafe {
        let serial = USB_SERIAL.as_mut().unwrap();

        serial.send_text("x");
        serial.send_number(report.x, 10);

        serial.send_text("y");
        serial.send_number(report.y, 10);
    });
}

#[allow(non_snake_case)]
#[interrupt]
unsafe fn USBCTRL_IRQ() {
    // Handle USB request
    let usb_dev = USB_DEVICE.as_mut().unwrap();
    let usb_hid = USB_SERIAL.as_mut().unwrap();
    usb_dev.poll(&mut [usb_hid]);
}