Return Self from Usbd::new

Author: Jonas Schievink

Cargo.toml

@@ -1,8 +1,6 @@
 [workspace]
-members = [
-    ".",
-    "example",
-]
+members = [".", "example"]
+default-members = [".", "example"]
 
 [package]
 name = "nrf-usbd"

example/src/main.rs

@@ -5,6 +5,7 @@ use defmt_rtt as _;
 use nrf_usbd::{UsbPeripheral, Usbd};
 // global logger
 use panic_probe as _;
+use usb_device::class_prelude::UsbBusAllocator;
 
 use core::str;
 use core::sync::atomic::{AtomicUsize, Ordering};
@@ -40,7 +41,7 @@ fn main() -> ! {
 
     info!("starting...");
 
-    let usb_bus = Usbd::new(Peripheral);
+    let usb_bus = UsbBusAllocator::new(Usbd::new(Peripheral));
     let mut serial = SerialPort::new(&usb_bus);
 
     let mut usb_dev = UsbDeviceBuilder::new(&usb_bus, UsbVidPid(0x16c0, 0x27dd))

src/usbd.rs

@@ -11,7 +11,7 @@ use core::mem::MaybeUninit;
 use core::sync::atomic::{compiler_fence, Ordering};
 use critical_section::{CriticalSection, Mutex};
 use usb_device::{
-    bus::{PollResult, UsbBus, UsbBusAllocator},
+    bus::{PollResult, UsbBus},
     endpoint::{EndpointAddress, EndpointType},
     UsbDirection, UsbError,
 };
@@ -57,6 +57,11 @@ struct EP0State {
 }
 
 /// USB device implementation.
+///
+/// This type implements the [`UsbBus`] trait and can be passed to a [`UsbBusAllocator`] to
+/// configure and use the USB device.
+///
+/// [`UsbBusAllocator`]: usb_device::bus::UsbBusAllocator
 pub struct Usbd<T: UsbPeripheral> {
     _periph: Mutex<T>,
     // argument passed to `UsbDeviceBuilder.max_packet_size_0`
@@ -71,14 +76,14 @@ pub struct Usbd<T: UsbPeripheral> {
 }
 
 impl<T: UsbPeripheral> Usbd<T> {
-    /// Creates a new USB bus, taking ownership of the raw peripheral.
+    /// Creates a new USB device wrapper, taking ownership of the raw peripheral.
     ///
     /// # Parameters
     ///
     /// * `periph`: The raw USBD peripheral.
     #[inline]
-    pub fn new(periph: T) -> UsbBusAllocator<Self> {
-        UsbBusAllocator::new(Self {
+    pub fn new(periph: T) -> Self {
+        Self {
             _periph: Mutex::new(periph),
             max_packet_size_0: 0,
             bufs: Buffers::new(),
@@ -93,7 +98,7 @@ impl<T: UsbPeripheral> Usbd<T> {
                 is_set_address: false,
             })),
             busy_in_endpoints: Mutex::new(Cell::new(0)),
-        })
+        }
     }
 
     fn regs<'a>(&self, _cs: &'a CriticalSection) -> &'a RegisterBlock {