Remove embassy_hal_common::usb.

The replacement is `embassy-usb`. There's a WIP driver for stm32 USBD in #709,
there's no WIP driver for stm32 USB_OTG. This means we're left without
USB_OTG support for now.

Reason for removing is I'm going to soon remove `embassy::io`, and
USB uses it. I don't want to spend time maintaining "dead" code
that is going to be removed. Volunteers welcome, either to update
old USB to the new IO, or write a USB_OTG driver fo the new USB.

14 files changed, 39 insertions, 1342 deletions

diff --git a/embassy-hal-common/Cargo.toml b/embassy-hal-common/Cargo.toml
index 2028b0e0c..fee6da6ff 100644
--- a/embassy-hal-common/Cargo.toml
+++ b/embassy-hal-common/Cargo.toml
@@ -12,5 +12,4 @@ embassy = { version = "0.1.0", path = "../embassy" }
 defmt = { version = "0.3", optional = true }
 log = { version = "0.4.14", optional = true }
 cortex-m = "0.7.3"
-usb-device = "0.2.8"
 num-traits = { version = "0.2.14", default-features = false }
diff --git a/embassy-hal-common/src/lib.rs b/embassy-hal-common/src/lib.rs
index 1af30c6b4..6ee2ccd59 100644
--- a/embassy-hal-common/src/lib.rs
+++ b/embassy-hal-common/src/lib.rs
@@ -10,7 +10,6 @@ mod macros;
 pub mod peripheral;
 pub mod ratio;
 pub mod ring_buffer;
-pub mod usb;
 
 /// Low power blocking wait loop using WFE/SEV.
 pub fn low_power_wait_until(mut condition: impl FnMut() -> bool) {
diff --git a/embassy-hal-common/src/usb/cdc_acm.rs b/embassy-hal-common/src/usb/cdc_acm.rs
deleted file mode 100644
index 5a85b3846..000000000
--- a/embassy-hal-common/src/usb/cdc_acm.rs
+++ /dev/null
@@ -1,338 +0,0 @@
-// Copied from https://github.com/mvirkkunen/usbd-serial
-#![allow(dead_code)]
-
-use core::convert::TryInto;
-use core::mem;
-use usb_device::class_prelude::*;
-use usb_device::Result;
-
-/// This should be used as `device_class` when building the `UsbDevice`.
-pub const USB_CLASS_CDC: u8 = 0x02;
-
-const USB_CLASS_CDC_DATA: u8 = 0x0a;
-const CDC_SUBCLASS_ACM: u8 = 0x02;
-const CDC_PROTOCOL_NONE: u8 = 0x00;
-
-const CS_INTERFACE: u8 = 0x24;
-const CDC_TYPE_HEADER: u8 = 0x00;
-const CDC_TYPE_CALL_MANAGEMENT: u8 = 0x01;
-const CDC_TYPE_ACM: u8 = 0x02;
-const CDC_TYPE_UNION: u8 = 0x06;
-
-const REQ_SEND_ENCAPSULATED_COMMAND: u8 = 0x00;
-#[allow(unused)]
-const REQ_GET_ENCAPSULATED_COMMAND: u8 = 0x01;
-const REQ_SET_LINE_CODING: u8 = 0x20;
-const REQ_GET_LINE_CODING: u8 = 0x21;
-const REQ_SET_CONTROL_LINE_STATE: u8 = 0x22;
-
-/// Packet level implementation of a CDC-ACM serial port.
-///
-/// This class can be used directly and it has the least overhead due to directly reading and
-/// writing USB packets with no intermediate buffers, but it will not act like a stream-like serial
-/// port. The following constraints must be followed if you use this class directly:
-///
-/// - `read_packet` must be called with a buffer large enough to hold max_packet_size bytes, and the
-///   method will return a `WouldBlock` error if there is no packet to be read.
-/// - `write_packet` must not be called with a buffer larger than max_packet_size bytes, and the
-///   method will return a `WouldBlock` error if the previous packet has not been sent yet.
-/// - If you write a packet that is exactly max_packet_size bytes long, it won't be processed by the
-///   host operating system until a subsequent shorter packet is sent. A zero-length packet (ZLP)
-///   can be sent if there is no other data to send. This is because USB bulk transactions must be
-///   terminated with a short packet, even if the bulk endpoint is used for stream-like data.
-pub struct CdcAcmClass<'a, B: UsbBus> {
-    comm_if: InterfaceNumber,
-    comm_ep: EndpointIn<'a, B>,
-    data_if: InterfaceNumber,
-    read_ep: EndpointOut<'a, B>,
-    write_ep: EndpointIn<'a, B>,
-    line_coding: LineCoding,
-    dtr: bool,
-    rts: bool,
-}
-
-impl<B: UsbBus> CdcAcmClass<'_, B> {
-    /// Creates a new CdcAcmClass with the provided UsbBus and max_packet_size in bytes. For
-    /// full-speed devices, max_packet_size has to be one of 8, 16, 32 or 64.
-    pub fn new(alloc: &UsbBusAllocator<B>, max_packet_size: u16) -> CdcAcmClass<'_, B> {
-        CdcAcmClass {
-            comm_if: alloc.interface(),
-            comm_ep: alloc.interrupt(8, 255),
-            data_if: alloc.interface(),
-            read_ep: alloc.bulk(max_packet_size),
-            write_ep: alloc.bulk(max_packet_size),
-            line_coding: LineCoding {
-                stop_bits: StopBits::One,
-                data_bits: 8,
-                parity_type: ParityType::None,
-                data_rate: 8_000,
-            },
-            dtr: false,
-            rts: false,
-        }
-    }
-
-    /// Gets the maximum packet size in bytes.
-    pub fn max_packet_size(&self) -> u16 {
-        // The size is the same for both endpoints.
-        self.read_ep.max_packet_size()
-    }
-
-    /// Gets the current line coding. The line coding contains information that's mainly relevant
-    /// for USB to UART serial port emulators, and can be ignored if not relevant.
-    pub fn line_coding(&self) -> &LineCoding {
-        &self.line_coding
-    }
-
-    /// Gets the DTR (data terminal ready) state
-    pub fn dtr(&self) -> bool {
-        self.dtr
-    }
-
-    /// Gets the RTS (request to send) state
-    pub fn rts(&self) -> bool {
-        self.rts
-    }
-
-    /// Writes a single packet into the IN endpoint.
-    pub fn write_packet(&mut self, data: &[u8]) -> Result<usize> {
-        self.write_ep.write(data)
-    }
-
-    /// Reads a single packet from the OUT endpoint.
-    pub fn read_packet(&mut self, data: &mut [u8]) -> Result<usize> {
-        self.read_ep.read(data)
-    }
-
-    /// Gets the address of the IN endpoint.
-    pub fn write_ep_address(&self) -> EndpointAddress {
-        self.write_ep.address()
-    }
-
-    /// Gets the address of the OUT endpoint.
-    pub fn read_ep_address(&self) -> EndpointAddress {
-        self.read_ep.address()
-    }
-}
-
-impl<B: UsbBus> UsbClass<B> for CdcAcmClass<'_, B> {
-    fn get_configuration_descriptors(&self, writer: &mut DescriptorWriter) -> Result<()> {
-        writer.iad(
-            self.comm_if,
-            2,
-            USB_CLASS_CDC,
-            CDC_SUBCLASS_ACM,
-            CDC_PROTOCOL_NONE,
-        )?;
-
-        writer.interface(
-            self.comm_if,
-            USB_CLASS_CDC,
-            CDC_SUBCLASS_ACM,
-            CDC_PROTOCOL_NONE,
-        )?;
-
-        writer.write(
-            CS_INTERFACE,
-            &[
-                CDC_TYPE_HEADER, // bDescriptorSubtype
-                0x10,
-                0x01, // bcdCDC (1.10)
-            ],
-        )?;
-
-        writer.write(
-            CS_INTERFACE,
-            &[
-                CDC_TYPE_ACM, // bDescriptorSubtype
-                0x00,         // bmCapabilities
-            ],
-        )?;
-
-        writer.write(
-            CS_INTERFACE,
-            &[
-                CDC_TYPE_UNION,      // bDescriptorSubtype
-                self.comm_if.into(), // bControlInterface
-                self.data_if.into(), // bSubordinateInterface
-            ],
-        )?;
-
-        writer.write(
-            CS_INTERFACE,
-            &[
-                CDC_TYPE_CALL_MANAGEMENT, // bDescriptorSubtype
-                0x00,                     // bmCapabilities
-                self.data_if.into(),      // bDataInterface
-            ],
-        )?;
-
-        writer.endpoint(&self.comm_ep)?;
-
-        writer.interface(self.data_if, USB_CLASS_CDC_DATA, 0x00, 0x00)?;
-
-        writer.endpoint(&self.write_ep)?;
-        writer.endpoint(&self.read_ep)?;
-
-        Ok(())
-    }
-
-    fn reset(&mut self) {
-        self.line_coding = LineCoding::default();
-        self.dtr = false;
-        self.rts = false;
-    }
-
-    fn control_in(&mut self, xfer: ControlIn<B>) {
-        let req = xfer.request();
-
-        if !(req.request_type == control::RequestType::Class
-            && req.recipient == control::Recipient::Interface
-            && req.index == u8::from(self.comm_if) as u16)
-        {
-            return;
-        }
-
-        match req.request {
-            // REQ_GET_ENCAPSULATED_COMMAND is not really supported - it will be rejected below.
-            REQ_GET_LINE_CODING if req.length == 7 => {
-                xfer.accept(|data| {
-                    data[0..4].copy_from_slice(&self.line_coding.data_rate.to_le_bytes());
-                    data[4] = self.line_coding.stop_bits as u8;
-                    data[5] = self.line_coding.parity_type as u8;
-                    data[6] = self.line_coding.data_bits;
-
-                    Ok(7)
-                })
-                .ok();
-            }
-            _ => {
-                xfer.reject().ok();
-            }
-        }
-    }
-
-    fn control_out(&mut self, xfer: ControlOut<B>) {
-        let req = xfer.request();
-
-        if !(req.request_type == control::RequestType::Class
-            && req.recipient == control::Recipient::Interface
-            && req.index == u8::from(self.comm_if) as u16)
-        {
-            return;
-        }
-
-        match req.request {
-            REQ_SEND_ENCAPSULATED_COMMAND => {
-                // We don't actually support encapsulated commands but pretend we do for standards
-                // compatibility.
-                xfer.accept().ok();
-            }
-            REQ_SET_LINE_CODING if xfer.data().len() >= 7 => {
-                self.line_coding.data_rate =
-                    u32::from_le_bytes(xfer.data()[0..4].try_into().unwrap());
-                self.line_coding.stop_bits = xfer.data()[4].into();
-                self.line_coding.parity_type = xfer.data()[5].into();
-                self.line_coding.data_bits = xfer.data()[6];
-
-                xfer.accept().ok();
-            }
-            REQ_SET_CONTROL_LINE_STATE => {
-                self.dtr = (req.value & 0x0001) != 0;
-                self.rts = (req.value & 0x0002) != 0;
-
-                xfer.accept().ok();
-            }
-            _ => {
-                xfer.reject().ok();
-            }
-        };
-    }
-}
-
-/// Number of stop bits for LineCoding
-#[derive(Copy, Clone, PartialEq, Eq)]
-pub enum StopBits {
-    /// 1 stop bit
-    One = 0,
-
-    /// 1.5 stop bits
-    OnePointFive = 1,
-
-    /// 2 stop bits
-    Two = 2,
-}
-
-impl From<u8> for StopBits {
-    fn from(value: u8) -> Self {
-        if value <= 2 {
-            unsafe { mem::transmute(value) }
-        } else {
-            StopBits::One
-        }
-    }
-}
-
-/// Parity for LineCoding
-#[derive(Copy, Clone, PartialEq, Eq)]
-pub enum ParityType {
-    None = 0,
-    Odd = 1,
-    Event = 2,
-    Mark = 3,
-    Space = 4,
-}
-
-impl From<u8> for ParityType {
-    fn from(value: u8) -> Self {
-        if value <= 4 {
-            unsafe { mem::transmute(value) }
-        } else {
-            ParityType::None
-        }
-    }
-}
-
-/// Line coding parameters
-///
-/// This is provided by the host for specifying the standard UART parameters such as baud rate. Can
-/// be ignored if you don't plan to interface with a physical UART.
-pub struct LineCoding {
-    stop_bits: StopBits,
-    data_bits: u8,
-    parity_type: ParityType,
-    data_rate: u32,
-}
-
-impl LineCoding {
-    /// Gets the number of stop bits for UART communication.
-    pub fn stop_bits(&self) -> StopBits {
-        self.stop_bits
-    }
-
-    /// Gets the number of data bits for UART communication.
-    pub fn data_bits(&self) -> u8 {
-        self.data_bits
-    }
-
-    /// Gets the parity type for UART communication.
-    pub fn parity_type(&self) -> ParityType {
-        self.parity_type
-    }
-
-    /// Gets the data rate in bits per second for UART communication.
-    pub fn data_rate(&self) -> u32 {
-        self.data_rate
-    }
-}
-
-impl Default for LineCoding {
-    fn default() -> Self {
-        LineCoding {
-            stop_bits: StopBits::One,
-            data_bits: 8,
-            parity_type: ParityType::None,
-            data_rate: 8_000,
-        }
-    }
-}
diff --git a/embassy-hal-common/src/usb/mod.rs b/embassy-hal-common/src/usb/mod.rs
deleted file mode 100644
index bab72d8b6..000000000
--- a/embassy-hal-common/src/usb/mod.rs
+++ /dev/null
@@ -1,267 +0,0 @@
-use core::cell::RefCell;
-use core::marker::PhantomData;
-use core::pin::Pin;
-
-use usb_device::bus::UsbBus;
-use usb_device::class::UsbClass;
-use usb_device::device::UsbDevice;
-
-mod cdc_acm;
-pub mod usb_serial;
-
-use crate::peripheral::{PeripheralMutex, PeripheralState, StateStorage};
-use embassy::interrupt::Interrupt;
-pub use usb_serial::{ReadInterface, UsbSerial, WriteInterface};
-
-/// Marker trait to mark an interrupt to be used with the [`Usb`] abstraction.
-pub unsafe trait USBInterrupt: Interrupt + Send {}
-
-pub struct State<'bus, B, T, I>(StateStorage<StateInner<'bus, B, T, I>>)
-where
-    B: UsbBus,
-    T: ClassSet<B>,
-    I: USBInterrupt;
-
-impl<'bus, B, T, I> State<'bus, B, T, I>
-where
-    B: UsbBus,
-    T: ClassSet<B>,
-    I: USBInterrupt,
-{
-    pub fn new() -> Self {
-        Self(StateStorage::new())
-    }
-}
-
-pub(crate) struct StateInner<'bus, B, T, I>
-where
-    B: UsbBus,
-    T: ClassSet<B>,
-    I: USBInterrupt,
-{
-    device: UsbDevice<'bus, B>,
-    pub(crate) classes: T,
-    _interrupt: PhantomData<I>,
-}
-
-pub struct Usb<'bus, B, T, I>
-where
-    B: UsbBus,
-    T: ClassSet<B>,
-    I: USBInterrupt,
-{
-    // Don't you dare moving out `PeripheralMutex`
-    inner: RefCell<PeripheralMutex<'bus, StateInner<'bus, B, T, I>>>,
-}
-
-impl<'bus, B, T, I> Usb<'bus, B, T, I>
-where
-    B: UsbBus,
-    T: ClassSet<B>,
-    I: USBInterrupt,
-{
-    /// safety: the returned instance is not leak-safe
-    pub unsafe fn new<S: IntoClassSet<B, T>>(
-        state: &'bus mut State<'bus, B, T, I>,
-        device: UsbDevice<'bus, B>,
-        class_set: S,
-        irq: I,
-    ) -> Self {
-        let mutex = PeripheralMutex::new_unchecked(irq, &mut state.0, || StateInner {
-            device,
-            classes: class_set.into_class_set(),
-            _interrupt: PhantomData,
-        });
-        Self {
-            inner: RefCell::new(mutex),
-        }
-    }
-}
-
-impl<'bus, 'c, B, T, I> Usb<'bus, B, T, I>
-where
-    B: UsbBus,
-    T: ClassSet<B> + SerialState<'bus, 'c, B, Index0>,
-    I: USBInterrupt,
-{
-    /// Take a serial class that was passed as the first class in a tuple
-    pub fn take_serial_0<'a>(
-        self: Pin<&'a Self>,
-    ) -> (
-        ReadInterface<'a, 'bus, 'c, Index0, B, T, I>,
-        WriteInterface<'a, 'bus, 'c, Index0, B, T, I>,
-    ) {
-        let this = self.get_ref();
-
-        let r = ReadInterface {
-            inner: &this.inner,
-            _buf_lifetime: PhantomData,
-            _index: PhantomData,
-        };
-
-        let w = WriteInterface {
-            inner: &this.inner,
-            _buf_lifetime: PhantomData,
-            _index: PhantomData,
-        };
-        (r, w)
-    }
-}
-
-impl<'bus, 'c, B, T, I> Usb<'bus, B, T, I>
-where
-    B: UsbBus,
-    T: ClassSet<B> + SerialState<'bus, 'c, B, Index1>,
-    I: USBInterrupt,
-{
-    /// Take a serial class that was passed as the second class in a tuple
-    pub fn take_serial_1<'a>(
-        self: Pin<&'a Self>,
-    ) -> (
-        ReadInterface<'a, 'bus, 'c, Index1, B, T, I>,
-        WriteInterface<'a, 'bus, 'c, Index1, B, T, I>,
-    ) {
-        let this = self.get_ref();
-
-        let r = ReadInterface {
-            inner: &this.inner,
-            _buf_lifetime: PhantomData,
-            _index: PhantomData,
-        };
-
-        let w = WriteInterface {
-            inner: &this.inner,
-            _buf_lifetime: PhantomData,
-            _index: PhantomData,
-        };
-        (r, w)
-    }
-}
-
-impl<'bus, B, T, I> PeripheralState for StateInner<'bus, B, T, I>
-where
-    B: UsbBus,
-    T: ClassSet<B>,
-    I: USBInterrupt,
-{
-    type Interrupt = I;
-    fn on_interrupt(&mut self) {
-        self.classes.poll_all(&mut self.device);
-    }
-}
-
-pub trait ClassSet<B: UsbBus>: Send {
-    fn poll_all(&mut self, device: &mut UsbDevice<'_, B>) -> bool;
-}
-
-pub trait IntoClassSet<B: UsbBus, C: ClassSet<B>> {
-    fn into_class_set(self) -> C;
-}
-
-pub struct ClassSet1<B, C1>
-where
-    B: UsbBus,
-    C1: UsbClass<B>,
-{
-    class: C1,
-    _bus: PhantomData<B>,
-}
-
-pub struct ClassSet2<B, C1, C2>
-where
-    B: UsbBus,
-    C1: UsbClass<B>,
-    C2: UsbClass<B>,
-{
-    class1: C1,
-    class2: C2,
-    _bus: PhantomData<B>,
-}
-
-/// The first class into a [`ClassSet`]
-pub struct Index0;
-
-/// The second class into a [`ClassSet`]
-pub struct Index1;
-
-impl<B, C1> ClassSet<B> for ClassSet1<B, C1>
-where
-    B: UsbBus + Send,
-    C1: UsbClass<B> + Send,
-{
-    fn poll_all(&mut self, device: &mut UsbDevice<'_, B>) -> bool {
-        device.poll(&mut [&mut self.class])
-    }
-}
-
-impl<B, C1, C2> ClassSet<B> for ClassSet2<B, C1, C2>
-where
-    B: UsbBus + Send,
-    C1: UsbClass<B> + Send,
-    C2: UsbClass<B> + Send,
-{
-    fn poll_all(&mut self, device: &mut UsbDevice<'_, B>) -> bool {
-        device.poll(&mut [&mut self.class1, &mut self.class2])
-    }
-}
-
-impl<B, C1> IntoClassSet<B, ClassSet1<B, C1>> for C1
-where
-    B: UsbBus + Send,
-    C1: UsbClass<B> + Send,
-{
-    fn into_class_set(self) -> ClassSet1<B, C1> {
-        ClassSet1 {
-            class: self,
-            _bus: PhantomData,
-        }
-    }
-}
-
-impl<B, C1, C2> IntoClassSet<B, ClassSet2<B, C1, C2>> for (C1, C2)
-where
-    B: UsbBus + Send,
-    C1: UsbClass<B> + Send,
-    C2: UsbClass<B> + Send,
-{
-    fn into_class_set(self) -> ClassSet2<B, C1, C2> {
-        ClassSet2 {
-            class1: self.0,
-            class2: self.1,
-            _bus: PhantomData,
-        }
-    }
-}
-
-/// Trait for a USB State that has a serial class inside
-pub trait SerialState<'bus, 'a, B: UsbBus, I> {
-    fn get_serial(&mut self) -> &mut UsbSerial<'bus, 'a, B>;
-}
-
-impl<'bus, 'a, B: UsbBus> SerialState<'bus, 'a, B, Index0>
-    for ClassSet1<B, UsbSerial<'bus, 'a, B>>
-{
-    fn get_serial(&mut self) -> &mut UsbSerial<'bus, 'a, B> {
-        &mut self.class
-    }
-}
-
-impl<'bus, 'a, B, C2> SerialState<'bus, 'a, B, Index0> for ClassSet2<B, UsbSerial<'bus, 'a, B>, C2>
-where
-    B: UsbBus,
-    C2: UsbClass<B>,
-{
-    fn get_serial(&mut self) -> &mut UsbSerial<'bus, 'a, B> {
-        &mut self.class1
-    }
-}
-
-impl<'bus, 'a, B, C1> SerialState<'bus, 'a, B, Index1> for ClassSet2<B, C1, UsbSerial<'bus, 'a, B>>
-where
-    B: UsbBus,
-    C1: UsbClass<B>,
-{
-    fn get_serial(&mut self) -> &mut UsbSerial<'bus, 'a, B> {
-        &mut self.class2
-    }
-}
diff --git a/embassy-hal-common/src/usb/usb_serial.rs b/embassy-hal-common/src/usb/usb_serial.rs
deleted file mode 100644
index 94f687890..000000000
--- a/embassy-hal-common/src/usb/usb_serial.rs
+++ /dev/null
@@ -1,345 +0,0 @@
-use core::cell::RefCell;
-use core::marker::{PhantomData, Unpin};
-use core::pin::Pin;
-use core::task::{Context, Poll};
-
-use embassy::io::{self, AsyncBufRead, AsyncWrite};
-use embassy::waitqueue::WakerRegistration;
-use usb_device::bus::UsbBus;
-use usb_device::class_prelude::*;
-use usb_device::UsbError;
-
-use super::cdc_acm::CdcAcmClass;
-use super::StateInner;
-use crate::peripheral::PeripheralMutex;
-use crate::ring_buffer::RingBuffer;
-use crate::usb::{ClassSet, SerialState, USBInterrupt};
-
-pub struct ReadInterface<'a, 'bus, 'c, I, B, T, INT>
-where
-    I: Unpin,
-    B: UsbBus,
-    T: SerialState<'bus, 'c, B, I> + ClassSet<B>,
-    INT: USBInterrupt,
-{
-    // Don't you dare moving out `PeripheralMutex`
-    pub(crate) inner: &'a RefCell<PeripheralMutex<'bus, StateInner<'bus, B, T, INT>>>,
-    pub(crate) _buf_lifetime: PhantomData<&'c T>,
-    pub(crate) _index: PhantomData<I>,
-}
-
-/// Write interface for USB CDC_ACM
-///
-/// This interface is buffered, meaning that after the write returns the bytes might not be fully
-/// on the wire just yet
-pub struct WriteInterface<'a, 'bus, 'c, I, B, T, INT>
-where
-    I: Unpin,
-    B: UsbBus,
-    T: SerialState<'bus, 'c, B, I> + ClassSet<B>,
-    INT: USBInterrupt,
-{
-    // Don't you dare moving out `PeripheralMutex`
-    pub(crate) inner: &'a RefCell<PeripheralMutex<'bus, StateInner<'bus, B, T, INT>>>,
-    pub(crate) _buf_lifetime: PhantomData<&'c T>,
-    pub(crate) _index: PhantomData<I>,
-}
-
-impl<'a, 'bus, 'c, I, B, T, INT> AsyncBufRead for ReadInterface<'a, 'bus, 'c, I, B, T, INT>
-where
-    I: Unpin,
-    B: UsbBus,
-    T: SerialState<'bus, 'c, B, I> + ClassSet<B>,
-    INT: USBInterrupt,
-{
-    fn poll_fill_buf(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<&[u8]>> {
-        let this = self.get_mut();
-        let mut mutex = this.inner.borrow_mut();
-        mutex.with(|state| {
-            let serial = state.classes.get_serial();
-            let serial = Pin::new(serial);
-
-            match serial.poll_fill_buf(cx) {
-                Poll::Ready(Ok(buf)) => {
-                    let buf: &[u8] = buf;
-                    // NOTE(unsafe) This part of the buffer won't be modified until the user calls
-                    // consume, which will invalidate this ref
-                    let buf: &[u8] = unsafe { core::mem::transmute(buf) };
-                    Poll::Ready(Ok(buf))
-                }
-                Poll::Ready(Err(_)) => Poll::Ready(Err(io::Error::Other)),
-                Poll::Pending => Poll::Pending,
-            }
-        })
-    }
-
-    fn consume(self: Pin<&mut Self>, amt: usize) {
-        let this = self.get_mut();
-        let mut mutex = this.inner.borrow_mut();
-        mutex.with(|state| {
-            let serial = state.classes.get_serial();
-            let serial = Pin::new(serial);
-
-            serial.consume(amt);
-        })
-    }
-}
-
-impl<'a, 'bus, 'c, I, B, T, INT> AsyncWrite for WriteInterface<'a, 'bus, 'c, I, B, T, INT>
-where
-    I: Unpin,
-    B: UsbBus,
-    T: SerialState<'bus, 'c, B, I> + ClassSet<B>,
-    INT: USBInterrupt,
-{
-    fn poll_write(
-        self: Pin<&mut Self>,
-        cx: &mut Context<'_>,
-        buf: &[u8],
-    ) -> Poll<io::Result<usize>> {
-        let this = self.get_mut();
-        let mut mutex = this.inner.borrow_mut();
-        mutex.with(|state| {
-            let serial = state.classes.get_serial();
-            let serial = Pin::new(serial);
-
-            serial.poll_write(cx, buf)
-        })
-    }
-
-    fn poll_flush(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<()>> {
-        let this = self.get_mut();
-        let mut mutex = this.inner.borrow_mut();
-        mutex.with(|state| {
-            let serial = state.classes.get_serial();
-            let serial = Pin::new(serial);
-
-            serial.poll_flush(cx)
-        })
-    }
-}
-
-pub struct UsbSerial<'bus, 'a, B: UsbBus> {
-    inner: CdcAcmClass<'bus, B>,
-    read_buf: RingBuffer<'a>,
-    write_buf: RingBuffer<'a>,
-    read_waker: WakerRegistration,
-    write_waker: WakerRegistration,
-    write_state: WriteState,
-    read_error: bool,
-    write_error: bool,
-}
-
-impl<'bus, 'a, B: UsbBus> AsyncBufRead for UsbSerial<'bus, 'a, B> {
-    fn poll_fill_buf(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<&[u8]>> {
-        let this = self.get_mut();
-
-        if this.read_error {
-            this.read_error = false;
-            return Poll::Ready(Err(io::Error::Other));
-        }
-
-        let buf = this.read_buf.pop_buf();
-        if buf.is_empty() {
-            this.read_waker.register(cx.waker());
-            return Poll::Pending;
-        }
-        Poll::Ready(Ok(buf))
-    }
-
-    fn consume(self: Pin<&mut Self>, amt: usize) {
-        self.get_mut().read_buf.pop(amt);
-    }
-}
-
-impl<'bus, 'a, B: UsbBus> AsyncWrite for UsbSerial<'bus, 'a, B> {
-    fn poll_write(
-        self: Pin<&mut Self>,
-        cx: &mut Context<'_>,
-        buf: &[u8],
-    ) -> Poll<io::Result<usize>> {
-        let this = self.get_mut();
-
-        if this.write_error {
-            this.write_error = false;
-            return Poll::Ready(Err(io::Error::Other));
-        }
-
-        let write_buf = this.write_buf.push_buf();
-        if write_buf.is_empty() {
-            trace!("buf full, registering waker");
-            this.write_waker.register(cx.waker());
-            return Poll::Pending;
-        }
-
-        let count = write_buf.len().min(buf.len());
-        write_buf[..count].copy_from_slice(&buf[..count]);
-        this.write_buf.push(count);
-
-        this.flush_write();
-        Poll::Ready(Ok(count))
-    }
-
-    fn poll_flush(self: Pin<&mut Self>, _cx: &mut Context<'_>) -> Poll<io::Result<()>> {
-        Poll::Ready(Ok(()))
-    }
-}
-
-/// Keeps track of the type of the last written packet.
-enum WriteState {
-    /// No packets in-flight
-    Idle,
-
-    /// Short packet currently in-flight
-    Short,
-
-    /// Full packet current in-flight. A full packet must be followed by a short packet for the host
-    /// OS to see the transaction. The data is the number of subsequent full packets sent so far. A
-    /// short packet is forced every SHORT_PACKET_INTERVAL packets so that the OS sees data in a
-    /// timely manner.
-    Full(usize),
-}
-
-impl<'bus, 'a, B: UsbBus> UsbSerial<'bus, 'a, B> {
-    pub fn new(
-        alloc: &'bus UsbBusAllocator<B>,
-        read_buf: &'a mut [u8],
-        write_buf: &'a mut [u8],
-    ) -> Self {
-        Self {
-            inner: CdcAcmClass::new(alloc, 64),
-            read_buf: RingBuffer::new(read_buf),
-            write_buf: RingBuffer::new(write_buf),
-            read_waker: WakerRegistration::new(),
-            write_waker: WakerRegistration::new(),
-            write_state: WriteState::Idle,
-            read_error: false,
-            write_error: false,
-        }
-    }
-
-    fn flush_write(&mut self) {
-        /// If this many full size packets have been sent in a row, a short packet will be sent so that the
-        /// host sees the data in a timely manner.
-        const SHORT_PACKET_INTERVAL: usize = 10;
-
-        let full_size_packets = match self.write_state {
-            WriteState::Full(c) => c,
-            _ => 0,
-        };
-
-        let ep_size = self.inner.max_packet_size() as usize;
-        let max_size = if full_size_packets > SHORT_PACKET_INTERVAL {
-            ep_size - 1
-        } else {
-            ep_size
-        };
-
-        let buf = {
-            let buf = self.write_buf.pop_buf();
-            if buf.len() > max_size {
-                &buf[..max_size]
-            } else {
-                buf
-            }
-        };
-
-        if !buf.is_empty() {
-            trace!("writing packet len {}", buf.len());
-            let count = match self.inner.write_packet(buf) {
-                Ok(c) => {
-                    trace!("write packet: OK {}", c);
-                    c
-                }
-                Err(UsbError::WouldBlock) => {
-                    trace!("write packet: WouldBlock");
-                    0
-                }
-                Err(_) => {
-                    trace!("write packet: error");
-                    self.write_error = true;
-                    return;
-                }
-            };
-
-            if buf.len() == ep_size {
-                self.write_state = WriteState::Full(full_size_packets + 1);
-            } else {
-                self.write_state = WriteState::Short;
-            }
-            self.write_buf.pop(count);
-        } else if full_size_packets > 0 {
-            trace!("writing empty packet");
-            match self.inner.write_packet(&[]) {
-                Ok(_) => {
-                    trace!("write empty packet: OK");
-                }
-                Err(UsbError::WouldBlock) => {
-                    trace!("write empty packet: WouldBlock");
-                    return;
-                }
-                Err(_) => {
-                    trace!("write empty packet: Error");
-                    self.write_error = true;
-                    return;
-                }
-            }
-            self.write_state = WriteState::Idle;
-        }
-    }
-}
-
-impl<B> UsbClass<B> for UsbSerial<'_, '_, B>
-where
-    B: UsbBus,
-{
-    fn get_configuration_descriptors(&self, writer: &mut DescriptorWriter) -> Result<(), UsbError> {
-        self.inner.get_configuration_descriptors(writer)
-    }
-
-    fn reset(&mut self) {
-        self.inner.reset();
-        self.read_buf.clear();
-        self.write_buf.clear();
-        self.write_state = WriteState::Idle;
-        self.read_waker.wake();
-        self.write_waker.wake();
-    }
-
-    fn endpoint_in_complete(&mut self, addr: EndpointAddress) {
-        trace!("DONE endpoint_in_complete");
-        if addr == self.inner.write_ep_address() {
-            trace!("DONE writing packet, waking");
-            self.write_waker.wake();
-
-            self.flush_write();
-        }
-    }
-
-    fn endpoint_out(&mut self, addr: EndpointAddress) {
-        if addr == self.inner.read_ep_address() {
-            let buf = self.read_buf.push_buf();
-            let count = match self.inner.read_packet(buf) {
-                Ok(c) => c,
-                Err(UsbError::WouldBlock) => 0,
-                Err(_) => {
-                    self.read_error = true;
-                    return;
-                }
-            };
-
-            if count > 0 {
-                self.read_buf.push(count);
-                self.read_waker.wake();
-            }
-        }
-    }
-
-    fn control_in(&mut self, xfer: ControlIn<B>) {
-        self.inner.control_in(xfer);
-    }
-
-    fn control_out(&mut self, xfer: ControlOut<B>) {
-        self.inner.control_out(xfer);
-    }
-}
diff --git a/embassy-stm32/Cargo.toml b/embassy-stm32/Cargo.toml
index 8152b07d4..ea9ac3b59 100644
--- a/embassy-stm32/Cargo.toml
+++ b/embassy-stm32/Cargo.toml
@@ -53,7 +53,6 @@ futures = { version = "0.3.17", default-features = false, features = ["async-awa
 rand_core = "0.6.3"
 sdio-host = "0.5.0"
 embedded-sdmmc = { git = "https://github.com/thalesfragoso/embedded-sdmmc-rs", branch = "async", optional = true }
-synopsys-usb-otg = { version = "0.3", features = ["cortex-m", "hs"], optional = true }
 critical-section = "0.2.5"
 bare-metal = "1.0.0"
 atomic-polyfill = "0.1.5"
@@ -76,7 +75,6 @@ net = ["embassy-net", "vcell"]
 memory-x = ["stm32-metapac/memory-x"]
 subghz = []
 exti = []
-usb-otg = ["synopsys-usb-otg"]
 
 # Features starting with `_` are for internal use only. They're not intended
 # to be enabled by other crates, and are not covered by semver guarantees.
diff --git a/embassy-stm32/build.rs b/embassy-stm32/build.rs
index aa3e64131..db757764f 100644
--- a/embassy-stm32/build.rs
+++ b/embassy-stm32/build.rs
@@ -279,22 +279,22 @@ fn main() {
         (("dcmi", "HSYNC"), (quote!(crate::dcmi::HSyncPin), quote!())),
         (("dcmi", "VSYNC"), (quote!(crate::dcmi::VSyncPin), quote!())),
         (("dcmi", "PIXCLK"), (quote!(crate::dcmi::PixClkPin), quote!())),
-        (("otgfs", "DP"), (quote!(crate::usb_otg::DpPin), quote!(#[cfg(feature="usb-otg")]))),
-        (("otgfs", "DM"), (quote!(crate::usb_otg::DmPin), quote!(#[cfg(feature="usb-otg")]))),
-        (("otghs", "DP"), (quote!(crate::usb_otg::DpPin), quote!(#[cfg(feature="usb-otg")]))),
-        (("otghs", "DM"), (quote!(crate::usb_otg::DmPin), quote!(#[cfg(feature="usb-otg")]))),
-        (("otghs", "ULPI_CK"), (quote!(crate::usb_otg::UlpiClkPin), quote!(#[cfg(feature="usb-otg")]))),
-        (("otghs", "ULPI_DIR"), (quote!(crate::usb_otg::UlpiDirPin), quote!(#[cfg(feature="usb-otg")]))),
-        (("otghs", "ULPI_NXT"), (quote!(crate::usb_otg::UlpiNxtPin), quote!(#[cfg(feature="usb-otg")]))),
-        (("otghs", "ULPI_STP"), (quote!(crate::usb_otg::UlpiStpPin), quote!(#[cfg(feature="usb-otg")]))),
-        (("otghs", "ULPI_D0"), (quote!(crate::usb_otg::UlpiD0Pin), quote!(#[cfg(feature="usb-otg")]))),
-        (("otghs", "ULPI_D1"), (quote!(crate::usb_otg::UlpiD1Pin), quote!(#[cfg(feature="usb-otg")]))),
-        (("otghs", "ULPI_D2"), (quote!(crate::usb_otg::UlpiD2Pin), quote!(#[cfg(feature="usb-otg")]))),
-        (("otghs", "ULPI_D3"), (quote!(crate::usb_otg::UlpiD3Pin), quote!(#[cfg(feature="usb-otg")]))),
-        (("otghs", "ULPI_D4"), (quote!(crate::usb_otg::UlpiD4Pin), quote!(#[cfg(feature="usb-otg")]))),
-        (("otghs", "ULPI_D5"), (quote!(crate::usb_otg::UlpiD5Pin), quote!(#[cfg(feature="usb-otg")]))),
-        (("otghs", "ULPI_D6"), (quote!(crate::usb_otg::UlpiD6Pin), quote!(#[cfg(feature="usb-otg")]))),
-        (("otghs", "ULPI_D7"), (quote!(crate::usb_otg::UlpiD7Pin), quote!(#[cfg(feature="usb-otg")]))),
+        (("otgfs", "DP"), (quote!(crate::usb_otg::DpPin), quote!())),
+        (("otgfs", "DM"), (quote!(crate::usb_otg::DmPin), quote!())),
+        (("otghs", "DP"), (quote!(crate::usb_otg::DpPin), quote!())),
+        (("otghs", "DM"), (quote!(crate::usb_otg::DmPin), quote!())),
+        (("otghs", "ULPI_CK"), (quote!(crate::usb_otg::UlpiClkPin), quote!())),
+        (("otghs", "ULPI_DIR"), (quote!(crate::usb_otg::UlpiDirPin), quote!())),
+        (("otghs", "ULPI_NXT"), (quote!(crate::usb_otg::UlpiNxtPin), quote!())),
+        (("otghs", "ULPI_STP"), (quote!(crate::usb_otg::UlpiStpPin), quote!())),
+        (("otghs", "ULPI_D0"), (quote!(crate::usb_otg::UlpiD0Pin), quote!())),
+        (("otghs", "ULPI_D1"), (quote!(crate::usb_otg::UlpiD1Pin), quote!())),
+        (("otghs", "ULPI_D2"), (quote!(crate::usb_otg::UlpiD2Pin), quote!())),
+        (("otghs", "ULPI_D3"), (quote!(crate::usb_otg::UlpiD3Pin), quote!())),
+        (("otghs", "ULPI_D4"), (quote!(crate::usb_otg::UlpiD4Pin), quote!())),
+        (("otghs", "ULPI_D5"), (quote!(crate::usb_otg::UlpiD5Pin), quote!())),
+        (("otghs", "ULPI_D6"), (quote!(crate::usb_otg::UlpiD6Pin), quote!())),
+        (("otghs", "ULPI_D7"), (quote!(crate::usb_otg::UlpiD7Pin), quote!())),
         (("can", "TX"), (quote!(crate::can::TxPin), quote!())),
         (("can", "RX"), (quote!(crate::can::RxPin), quote!())),
         (("eth", "REF_CLK"), (quote!(crate::eth::RefClkPin), quote!(#[cfg(feature="net")]))),
diff --git a/embassy-stm32/src/lib.rs b/embassy-stm32/src/lib.rs
index ba426128f..6e9077b4c 100644
--- a/embassy-stm32/src/lib.rs
+++ b/embassy-stm32/src/lib.rs
@@ -61,7 +61,7 @@ pub mod sdmmc;
 pub mod spi;
 #[cfg(usart)]
 pub mod usart;
-#[cfg(feature = "usb-otg")]
+#[cfg(any(otgfs, otghs))]
 pub mod usb_otg;
 
 #[cfg(feature = "subghz")]
diff --git a/embassy-stm32/src/usb_otg.rs b/embassy-stm32/src/usb_otg.rs
index 8c2c1e99c..21b890d7c 100644
--- a/embassy-stm32/src/usb_otg.rs
+++ b/embassy-stm32/src/usb_otg.rs
@@ -1,15 +1,11 @@
 use core::marker::PhantomData;
 use embassy::util::Unborrow;
 use embassy_hal_common::unborrow;
-use synopsys_usb_otg::{PhyType, UsbPeripheral};
 
 use crate::gpio::sealed::AFType;
 use crate::gpio::Speed;
 use crate::{peripherals, rcc::RccPeripheral};
 
-pub use embassy_hal_common::usb::*;
-pub use synopsys_usb_otg::UsbBus;
-
 macro_rules! config_ulpi_pins {
     ($($pin:ident),*) => {
         unborrow!($($pin),*);
@@ -23,9 +19,24 @@ macro_rules! config_ulpi_pins {
     };
 }
 
+/// USB PHY type
+#[derive(Copy, Clone, Debug, Eq, PartialEq)]
+pub enum PhyType {
+    /// Internal Full-Speed PHY
+    ///
+    /// Available on most High-Speed peripherals.
+    InternalFullSpeed,
+    /// Internal High-Speed PHY
+    ///
+    /// Available on a few STM32 chips.
+    InternalHighSpeed,
+    /// External ULPI High-Speed PHY
+    ExternalHighSpeed,
+}
+
 pub struct UsbOtg<'d, T: Instance> {
     phantom: PhantomData<&'d mut T>,
-    phy_type: PhyType,
+    _phy_type: PhyType,
 }
 
 impl<'d, T: Instance> UsbOtg<'d, T> {
@@ -44,7 +55,7 @@ impl<'d, T: Instance> UsbOtg<'d, T> {
 
         Self {
             phantom: PhantomData,
-            phy_type: PhyType::InternalFullSpeed,
+            _phy_type: PhyType::InternalFullSpeed,
         }
     }
 
@@ -71,7 +82,7 @@ impl<'d, T: Instance> UsbOtg<'d, T> {
 
         Self {
             phantom: PhantomData,
-            phy_type: PhyType::ExternalHighSpeed,
+            _phy_type: PhyType::ExternalHighSpeed,
         }
     }
 }
@@ -83,29 +94,6 @@ impl<'d, T: Instance> Drop for UsbOtg<'d, T> {
     }
 }
 
-unsafe impl<'d, T: Instance> Send for UsbOtg<'d, T> {}
-unsafe impl<'d, T: Instance> Sync for UsbOtg<'d, T> {}
-
-unsafe impl<'d, T: Instance> UsbPeripheral for UsbOtg<'d, T> {
-    const REGISTERS: *const () = T::REGISTERS;
-    const HIGH_SPEED: bool = T::HIGH_SPEED;
-    const FIFO_DEPTH_WORDS: usize = T::FIFO_DEPTH_WORDS;
-    const ENDPOINT_COUNT: usize = T::ENDPOINT_COUNT;
-
-    fn enable() {
-        <T as crate::rcc::sealed::RccPeripheral>::enable();
-        <T as crate::rcc::sealed::RccPeripheral>::reset();
-    }
-
-    fn phy_type(&self) -> PhyType {
-        self.phy_type
-    }
-
-    fn ahb_frequency_hz(&self) -> u32 {
-        <T as crate::rcc::sealed::RccPeripheral>::frequency().0
-    }
-}
-
 pub(crate) mod sealed {
     pub trait Instance {
         const REGISTERS: *const ();
@@ -177,7 +165,7 @@ foreach_peripheral!(
                     const FIFO_DEPTH_WORDS: usize = 512;
                     const ENDPOINT_COUNT: usize = 8;
                 } else {
-                    compile_error!("USB_OTG_FS peripheral is not supported by this chip. Disable \"usb-otg-fs\" feature or select a different chip.");
+                    compile_error!("USB_OTG_FS peripheral is not supported by this chip.");
                 }
             }
         }
@@ -214,7 +202,7 @@ foreach_peripheral!(
                     const FIFO_DEPTH_WORDS: usize = 1024;
                     const ENDPOINT_COUNT: usize = 9;
                 } else {
-                    compile_error!("USB_OTG_HS peripheral is not supported by this chip. Disable \"usb-otg-hs\" feature or select a different chip.");
+                    compile_error!("USB_OTG_HS peripheral is not supported by this chip.");
                 }
             }
         }
@@ -222,12 +210,3 @@ foreach_peripheral!(
         impl Instance for peripherals::$inst {}
     };
 );
-
-foreach_interrupt!(
-    ($inst:ident, otgfs, $block:ident, GLOBAL, $irq:ident) => {
-        unsafe impl USBInterrupt for crate::interrupt::$irq {}
-    };
-    ($inst:ident, otghs, $block:ident, GLOBAL, $irq:ident) => {
-        unsafe impl USBInterrupt for crate::interrupt::$irq {}
-    };
-);
diff --git a/examples/stm32f4/Cargo.toml b/examples/stm32f4/Cargo.toml
index 1bc406495..e2065bed9 100644
--- a/examples/stm32f4/Cargo.toml
+++ b/examples/stm32f4/Cargo.toml
@@ -8,7 +8,7 @@ resolver = "2"
 
 [dependencies]
 embassy = { version = "0.1.0", path = "../../embassy", features = ["defmt", "defmt-timestamp-uptime", "unstable-traits"] }
-embassy-stm32 = { version = "0.1.0", path = "../../embassy-stm32", features = ["nightly", "unstable-traits", "defmt", "stm32f429zi", "unstable-pac", "memory-x", "time-driver-any", "exti", "usb-otg"]  }
+embassy-stm32 = { version = "0.1.0", path = "../../embassy-stm32", features = ["nightly", "unstable-traits", "defmt", "stm32f429zi", "unstable-pac", "memory-x", "time-driver-any", "exti"]  }
 
 defmt = "0.3"
 defmt-rtt = "0.3"
diff --git a/examples/stm32f4/src/bin/usb_uart.rs b/examples/stm32f4/src/bin/usb_uart.rs
deleted file mode 100644
index 251ed1eb0..000000000
--- a/examples/stm32f4/src/bin/usb_uart.rs
+++ /dev/null
@@ -1,99 +0,0 @@
-#![no_std]
-#![no_main]
-#![feature(type_alias_impl_trait)]
-
-use defmt_rtt as _; // global logger
-use panic_probe as _;
-
-use defmt::{info, unwrap};
-use defmt_rtt as _; // global logger
-use embassy::interrupt::InterruptExt;
-use futures::pin_mut;
-use panic_probe as _; // print out panic messages
-
-use embassy::executor::Spawner;
-use embassy::io::{AsyncBufReadExt, AsyncWriteExt};
-use embassy_stm32::usb_otg::{State, Usb, UsbBus, UsbOtg, UsbSerial};
-use embassy_stm32::{interrupt, time::Hertz, Config, Peripherals};
-use usb_device::device::{UsbDeviceBuilder, UsbVidPid};
-
-static mut EP_MEMORY: [u32; 2048] = [0; 2048];
-
-// USB requires at least 48 MHz clock
-fn config() -> Config {
-    let mut config = Config::default();
-    config.rcc.sys_ck = Some(Hertz(48_000_000));
-    config
-}
-
-#[embassy::main(config = "config()")]
-async fn main(_spawner: Spawner, p: Peripherals) {
-    let mut rx_buffer = [0u8; 64];
-    // we send back input + cr + lf
-    let mut tx_buffer = [0u8; 66];
-
-    let peri = UsbOtg::new_fs(p.USB_OTG_FS, p.PA12, p.PA11);
-    let usb_bus = UsbBus::new(peri, unsafe { &mut EP_MEMORY });
-
-    let serial = UsbSerial::new(&usb_bus, &mut rx_buffer, &mut tx_buffer);
-
-    let device = UsbDeviceBuilder::new(&usb_bus, UsbVidPid(0x16c0, 0x27dd))
-        .manufacturer("Fake company")
-        .product("Serial port")
-        .serial_number("TEST")
-        .device_class(0x02)
-        .build();
-
-    let irq = interrupt::take!(OTG_FS);
-    irq.set_priority(interrupt::Priority::P3);
-
-    let mut state = State::new();
-    let usb = unsafe { Usb::new(&mut state, device, serial, irq) };
-    pin_mut!(usb);
-
-    let (mut reader, mut writer) = usb.as_ref().take_serial_0();
-
-    info!("usb initialized!");
-
-    unwrap!(
-        writer
-            .write_all(b"\r\nInput returned upper cased on CR+LF\r\n")
-            .await
-    );
-
-    let mut buf = [0u8; 64];
-    loop {
-        let mut n = 0;
-
-        async {
-            loop {
-                let char = unwrap!(reader.read_byte().await);
-
-                if char == b'\r' || char == b'\n' {
-                    break;
-                }
-
-                buf[n] = char;
-                n += 1;
-
-                // stop if we're out of room
-                if n == buf.len() {
-                    break;
-                }
-            }
-        }
-        .await;
-
-        if n > 0 {
-            for char in buf[..n].iter_mut() {
-                // upper case
-                if 0x61 <= *char && *char <= 0x7a {
-                    *char &= !0x20;
-                }
-            }
-            unwrap!(writer.write_all(&buf[..n]).await);
-            unwrap!(writer.write_all(b"\r\n").await);
-            unwrap!(writer.flush().await);
-        }
-    }
-}
diff --git a/examples/stm32f4/src/bin/usb_uart_ulpi.rs b/examples/stm32f4/src/bin/usb_uart_ulpi.rs
deleted file mode 100644
index f6c373602..000000000
--- a/examples/stm32f4/src/bin/usb_uart_ulpi.rs
+++ /dev/null
@@ -1,114 +0,0 @@
-#![no_std]
-#![no_main]
-#![feature(type_alias_impl_trait)]
-
-use defmt_rtt as _; // global logger
-use panic_probe as _;
-
-use defmt::{info, unwrap};
-use defmt_rtt as _; // global logger
-use embassy::interrupt::InterruptExt;
-use futures::pin_mut;
-use panic_probe as _; // print out panic messages
-
-use embassy::executor::Spawner;
-use embassy::io::{AsyncBufReadExt, AsyncWriteExt};
-use embassy_stm32::usb_otg::{State, Usb, UsbBus, UsbOtg, UsbSerial};
-use embassy_stm32::{interrupt, time::Hertz, Config, Peripherals};
-use usb_device::device::{UsbDeviceBuilder, UsbVidPid};
-
-static mut EP_MEMORY: [u32; 2048] = [0; 2048];
-
-// USB requires at least 48 MHz clock
-fn config() -> Config {
-    let mut config = Config::default();
-    config.rcc.sys_ck = Some(Hertz(48_000_000));
-    config
-}
-
-#[embassy::main(config = "config()")]
-async fn main(_spawner: Spawner, p: Peripherals) {
-    let mut rx_buffer = [0u8; 64];
-    // we send back input + cr + lf
-    let mut tx_buffer = [0u8; 66];
-
-    // USB with external high-speed PHY
-    let peri = UsbOtg::new_hs_ulpi(
-        p.USB_OTG_HS,
-        p.PA5,
-        p.PC2,
-        p.PC3,
-        p.PC0,
-        p.PA3,
-        p.PB0,
-        p.PB1,
-        p.PB10,
-        p.PB11,
-        p.PB12,
-        p.PB13,
-        p.PB5,
-    );
-    let usb_bus = UsbBus::new(peri, unsafe { &mut EP_MEMORY });
-
-    let serial = UsbSerial::new(&usb_bus, &mut rx_buffer, &mut tx_buffer);
-
-    let device = UsbDeviceBuilder::new(&usb_bus, UsbVidPid(0x16c0, 0x27dd))
-        .manufacturer("Fake company")
-        .product("Serial port")
-        .serial_number("TEST")
-        .device_class(0x02)
-        .build();
-
-    let irq = interrupt::take!(OTG_FS);
-    irq.set_priority(interrupt::Priority::P3);
-
-    let mut state = State::new();
-    let usb = unsafe { Usb::new(&mut state, device, serial, irq) };
-    pin_mut!(usb);
-
-    let (mut reader, mut writer) = usb.as_ref().take_serial_0();
-
-    info!("usb initialized!");
-
-    unwrap!(
-        writer
-            .write_all(b"\r\nInput returned upper cased on CR+LF\r\n")
-            .await
-    );
-
-    let mut buf = [0u8; 64];
-    loop {
-        let mut n = 0;
-
-        async {
-            loop {
-                let char = unwrap!(reader.read_byte().await);
-
-                if char == b'\r' || char == b'\n' {
-                    break;
-                }
-
-                buf[n] = char;
-                n += 1;
-
-                // stop if we're out of room
-                if n == buf.len() {
-                    break;
-                }
-            }
-        }
-        .await;
-
-        if n > 0 {
-            for char in buf[..n].iter_mut() {
-                // upper case
-                if 0x61 <= *char && *char <= 0x7a {
-                    *char &= !0x20;
-                }
-            }
-            unwrap!(writer.write_all(&buf[..n]).await);
-            unwrap!(writer.write_all(b"\r\n").await);
-            unwrap!(writer.flush().await);
-        }
-    }
-}
diff --git a/examples/stm32l4/Cargo.toml b/examples/stm32l4/Cargo.toml
index 2da549bb2..b3478f74e 100644
--- a/examples/stm32l4/Cargo.toml
+++ b/examples/stm32l4/Cargo.toml
@@ -10,7 +10,7 @@ resolver = "2"
 [dependencies]
 embassy = { version = "0.1.0", path = "../../embassy", features = ["defmt", "defmt-timestamp-uptime"] }
 embassy-traits = { version = "0.1.0", path = "../../embassy-traits" }
-embassy-stm32 = { version = "0.1.0", path = "../../embassy-stm32", features = ["nightly", "defmt", "unstable-pac", "stm32l4s5vi", "time-driver-any", "exti", "unstable-traits", "usb-otg"]  }
+embassy-stm32 = { version = "0.1.0", path = "../../embassy-stm32", features = ["nightly", "defmt", "unstable-pac", "stm32l4s5vi", "time-driver-any", "exti", "unstable-traits"]  }
 
 defmt = "0.3"
 defmt-rtt = "0.3"
diff --git a/examples/stm32l4/src/bin/usb_uart.rs b/examples/stm32l4/src/bin/usb_uart.rs
deleted file mode 100644
index 878309550..000000000
--- a/examples/stm32l4/src/bin/usb_uart.rs
+++ /dev/null
@@ -1,115 +0,0 @@
-#![no_std]
-#![no_main]
-#![feature(type_alias_impl_trait)]
-
-use defmt_rtt as _; // global logger
-use panic_probe as _;
-
-use defmt::{info, unwrap};
-use defmt_rtt as _; // global logger
-use embassy::interrupt::InterruptExt;
-use futures::pin_mut;
-use panic_probe as _; // print out panic messages
-
-use embassy::executor::Spawner;
-use embassy::io::{AsyncBufReadExt, AsyncWriteExt};
-use embassy_stm32::pac::pwr::vals::Usv;
-use embassy_stm32::pac::{PWR, RCC};
-use embassy_stm32::rcc::{ClockSrc, PLLClkDiv, PLLMul, PLLSource, PLLSrcDiv};
-use embassy_stm32::usb_otg::{State, Usb, UsbBus, UsbOtg, UsbSerial};
-use embassy_stm32::{interrupt, Config, Peripherals};
-use usb_device::device::{UsbDeviceBuilder, UsbVidPid};
-
-static mut EP_MEMORY: [u32; 2048] = [0; 2048];
-
-// USB requires at least 48 MHz clock
-fn config() -> Config {
-    let mut config = Config::default();
-    // set up a 80Mhz clock
-    config.rcc.mux = ClockSrc::PLL(
-        PLLSource::HSI16,
-        PLLClkDiv::Div2,
-        PLLSrcDiv::Div2,
-        PLLMul::Mul20,
-        None,
-    );
-    // enable HSI48 clock for USB
-    config.rcc.hsi48 = true;
-    config
-}
-
-#[embassy::main(config = "config()")]
-async fn main(_spawner: Spawner, p: Peripherals) {
-    // Enable PWR peripheral
-    unsafe { RCC.apb1enr1().modify(|w| w.set_pwren(true)) };
-    unsafe { PWR.cr2().modify(|w| w.set_usv(Usv::VALID)) }
-
-    let mut rx_buffer = [0u8; 64];
-    // we send back input + cr + lf
-    let mut tx_buffer = [0u8; 66];
-
-    let peri = UsbOtg::new_fs(p.USB_OTG_FS, p.PA12, p.PA11);
-    let usb_bus = UsbBus::new(peri, unsafe { &mut EP_MEMORY });
-
-    let serial = UsbSerial::new(&usb_bus, &mut rx_buffer, &mut tx_buffer);
-
-    let device = UsbDeviceBuilder::new(&usb_bus, UsbVidPid(0x16c0, 0x27dd))
-        .manufacturer("Fake company")
-        .product("Serial port")
-        .serial_number("TEST")
-        .device_class(0x02)
-        .build();
-
-    let irq = interrupt::take!(OTG_FS);
-    irq.set_priority(interrupt::Priority::P3);
-
-    let mut state = State::new();
-    let usb = unsafe { Usb::new(&mut state, device, serial, irq) };
-    pin_mut!(usb);
-
-    let (mut reader, mut writer) = usb.as_ref().take_serial_0();
-
-    info!("usb initialized!");
-
-    unwrap!(
-        writer
-            .write_all(b"\r\nInput returned upper cased on CR+LF\r\n")
-            .await
-    );
-
-    let mut buf = [0u8; 64];
-    loop {
-        let mut n = 0;
-
-        async {
-            loop {
-                let char = unwrap!(reader.read_byte().await);
-
-                if char == b'\r' || char == b'\n' {
-                    break;
-                }
-
-                buf[n] = char;
-                n += 1;
-
-                // stop if we're out of room
-                if n == buf.len() {
-                    break;
-                }
-            }
-        }
-        .await;
-
-        if n > 0 {
-            for char in buf[..n].iter_mut() {
-                // upper case
-                if 0x61 <= *char && *char <= 0x7a {
-                    *char &= !0x20;
-                }
-            }
-            unwrap!(writer.write_all(&buf[..n]).await);
-            unwrap!(writer.write_all(b"\r\n").await);
-            unwrap!(writer.flush().await);
-        }
-    }
-}