Add support for USB classes handling control requests.

5 files changed, 313 insertions, 119 deletions

diff --git a/embassy-usb/src/builder.rs b/embassy-usb/src/builder.rs
index e92cc8ef2..f0f94b932 100644
--- a/embassy-usb/src/builder.rs
+++ b/embassy-usb/src/builder.rs
@@ -1,3 +1,4 @@
+use super::class::UsbClass;
 use super::descriptor::{BosWriter, DescriptorWriter};
 use super::driver::{Driver, EndpointAllocError};
 use super::types::*;
@@ -174,7 +175,10 @@ impl<'d, D: Driver<'d>> UsbDeviceBuilder<'d, D> {
     }
 
     /// Creates the [`UsbDevice`] instance with the configuration in this builder.
-    pub fn build(mut self) -> UsbDevice<'d, D> {
+    ///
+    /// If a device has mutliple [`UsbClass`]es, they can be provided as a tuple list:
+    /// `(class1, (class2, (class3, ()))`.
+    pub fn build<C: UsbClass<'d, D>>(mut self, classes: C) -> UsbDevice<'d, D, C> {
         self.config_descriptor.end_configuration();
         self.bos_descriptor.end_bos();
 
@@ -184,6 +188,7 @@ impl<'d, D: Driver<'d>> UsbDeviceBuilder<'d, D> {
             self.device_descriptor.into_buf(),
             self.config_descriptor.into_buf(),
             self.bos_descriptor.writer.into_buf(),
+            classes,
         )
     }
 
@@ -268,9 +273,10 @@ impl<'d, D: Driver<'d>> UsbDeviceBuilder<'d, D> {
     /// Panics if endpoint allocation fails, because running out of endpoints or memory is not
     /// feasibly recoverable.
     #[inline]
-    pub fn alloc_control_endpoint_out(&mut self, max_packet_size: u16) -> D::EndpointOut {
-        self.alloc_endpoint_out(None, EndpointType::Control, max_packet_size, 0)
-            .expect("alloc_ep failed")
+    pub fn alloc_control_pipe(&mut self, max_packet_size: u16) -> D::ControlPipe {
+        self.bus
+            .alloc_control_pipe(max_packet_size)
+            .expect("alloc_control_pipe failed")
     }
 
     /// Allocates a bulk in endpoint.
diff --git a/embassy-usb/src/class.rs b/embassy-usb/src/class.rs
new file mode 100644
index 000000000..97bf7aba1
--- /dev/null
+++ b/embassy-usb/src/class.rs
@@ -0,0 +1,190 @@
+use core::future::Future;
+
+use crate::control::Request;
+use crate::driver::{ControlPipe, Driver};
+
+#[derive(Copy, Clone, Eq, PartialEq, Debug)]
+#[cfg_attr(feature = "defmt", derive(defmt::Format))]
+pub enum RequestStatus {
+    Unhandled,
+    Accepted,
+    Rejected,
+}
+
+impl Default for RequestStatus {
+    fn default() -> Self {
+        RequestStatus::Unhandled
+    }
+}
+
+/// A trait for implementing USB classes.
+///
+/// All methods are optional callbacks that will be called by
+/// [`UsbDevice::run()`](crate::UsbDevice::run)
+pub trait UsbClass<'d, D: Driver<'d>> {
+    type ControlOutFuture<'a>: Future<Output = RequestStatus> + 'a
+    where
+        Self: 'a,
+        'd: 'a,
+        D: 'a;
+
+    type ControlInFuture<'a>: Future<Output = ControlInRequestStatus> + 'a
+    where
+        Self: 'a,
+        'd: 'a,
+        D: 'a;
+
+    /// Called after a USB reset after the bus reset sequence is complete.
+    fn reset(&mut self) {}
+
+    /// Called when a control request is received with direction HostToDevice.
+    ///
+    /// All requests are passed to classes in turn, which can choose to accept, ignore or report an
+    /// error. Classes can even choose to override standard requests, but doing that is rarely
+    /// necessary.
+    ///
+    /// When implementing your own class, you should ignore any requests that are not meant for your
+    /// class so that any other classes in the composite device can process them.
+    ///
+    /// # Arguments
+    ///
+    /// * `req` - The request from the SETUP packet.
+    /// * `data` - The data from the request.
+    fn control_out<'a>(&'a mut self, req: Request, data: &'a [u8]) -> Self::ControlOutFuture<'a>
+    where
+        'd: 'a,
+        D: 'a;
+
+    /// Called when a control request is received with direction DeviceToHost.
+    ///
+    /// All requests are passed to classes in turn, which can choose to accept, ignore or report an
+    /// error. Classes can even choose to override standard requests, but doing that is rarely
+    /// necessary.
+    ///
+    /// See [`ControlIn`] for how to respond to the transfer.
+    ///
+    /// When implementing your own class, you should ignore any requests that are not meant for your
+    /// class so that any other classes in the composite device can process them.
+    ///
+    /// # Arguments
+    ///
+    /// * `req` - The request from the SETUP packet.
+    /// * `control` - The control pipe.
+    fn control_in<'a>(
+        &'a mut self,
+        req: Request,
+        control: ControlIn<'a, 'd, D>,
+    ) -> Self::ControlInFuture<'a>
+    where
+        'd: 'a;
+}
+
+impl<'d, D: Driver<'d>> UsbClass<'d, D> for () {
+    type ControlOutFuture<'a> = impl Future<Output = RequestStatus> + 'a where Self: 'a, 'd: 'a, D: 'a;
+    type ControlInFuture<'a> = impl Future<Output = ControlInRequestStatus> + 'a where Self: 'a, 'd: 'a, D: 'a;
+
+    fn control_out<'a>(&'a mut self, _req: Request, _data: &'a [u8]) -> Self::ControlOutFuture<'a>
+    where
+        'd: 'a,
+        D: 'a,
+    {
+        async move { RequestStatus::default() }
+    }
+
+    fn control_in<'a>(
+        &'a mut self,
+        _req: Request,
+        control: ControlIn<'a, 'd, D>,
+    ) -> Self::ControlInFuture<'a>
+    where
+        'd: 'a,
+        D: 'a,
+    {
+        async move { control.ignore() }
+    }
+}
+
+impl<'d, D: Driver<'d>, Head, Tail> UsbClass<'d, D> for (Head, Tail)
+where
+    Head: UsbClass<'d, D>,
+    Tail: UsbClass<'d, D>,
+{
+    type ControlOutFuture<'a> = impl Future<Output = RequestStatus> + 'a where Self: 'a, 'd: 'a, D: 'a;
+    type ControlInFuture<'a> = impl Future<Output = ControlInRequestStatus> + 'a where Self: 'a, 'd: 'a, D: 'a;
+
+    fn control_out<'a>(&'a mut self, req: Request, data: &'a [u8]) -> Self::ControlOutFuture<'a>
+    where
+        'd: 'a,
+        D: 'a,
+    {
+        async move {
+            match self.0.control_out(req, data).await {
+                RequestStatus::Unhandled => self.1.control_out(req, data).await,
+                status => status,
+            }
+        }
+    }
+
+    fn control_in<'a>(
+        &'a mut self,
+        req: Request,
+        control: ControlIn<'a, 'd, D>,
+    ) -> Self::ControlInFuture<'a>
+    where
+        'd: 'a,
+    {
+        async move {
+            match self
+                .0
+                .control_in(req, ControlIn::new(control.control))
+                .await
+            {
+                ControlInRequestStatus(RequestStatus::Unhandled) => {
+                    self.1.control_in(req, control).await
+                }
+                status => status,
+            }
+        }
+    }
+}
+
+/// Handle for a control IN transfer. When implementing a class, use the methods of this object to
+/// response to the transfer with either data or an error (STALL condition). To ignore the request
+/// and pass it on to the next class, call [`Self::ignore()`].
+pub struct ControlIn<'a, 'd: 'a, D: Driver<'d>> {
+    control: &'a mut D::ControlPipe,
+}
+
+#[derive(Eq, PartialEq, Debug)]
+#[cfg_attr(feature = "defmt", derive(defmt::Format))]
+pub struct ControlInRequestStatus(pub(crate) RequestStatus);
+
+impl ControlInRequestStatus {
+    pub fn status(self) -> RequestStatus {
+        self.0
+    }
+}
+
+impl<'a, 'd: 'a, D: Driver<'d>> ControlIn<'a, 'd, D> {
+    pub(crate) fn new(control: &'a mut D::ControlPipe) -> Self {
+        ControlIn { control }
+    }
+
+    /// Ignores the request and leaves it unhandled.
+    pub fn ignore(self) -> ControlInRequestStatus {
+        ControlInRequestStatus(RequestStatus::Unhandled)
+    }
+
+    /// Accepts the transfer with the supplied buffer.
+    pub async fn accept(self, data: &[u8]) -> ControlInRequestStatus {
+        self.control.accept_in(data).await;
+
+        ControlInRequestStatus(RequestStatus::Accepted)
+    }
+
+    /// Rejects the transfer by stalling the pipe.
+    pub fn reject(self) -> ControlInRequestStatus {
+        self.control.reject();
+        ControlInRequestStatus(RequestStatus::Rejected)
+    }
+}
diff --git a/embassy-usb/src/control.rs b/embassy-usb/src/control.rs
index f1148ac76..77bc10aa4 100644
--- a/embassy-usb/src/control.rs
+++ b/embassy-usb/src/control.rs
@@ -2,12 +2,6 @@ use core::mem;
 
 use super::types::*;
 
-#[derive(Debug, PartialEq, Eq, Clone, Copy)]
-#[cfg_attr(feature = "defmt", derive(defmt::Format))]
-pub enum ParseError {
-    InvalidLength,
-}
-
 /// Control request type.
 #[repr(u8)]
 #[derive(Copy, Clone, Eq, PartialEq, Debug)]
@@ -104,15 +98,12 @@ impl Request {
     /// Standard USB feature Device Remote Wakeup for Set/Clear Feature
     pub const FEATURE_DEVICE_REMOTE_WAKEUP: u16 = 1;
 
-    pub(crate) fn parse(buf: &[u8]) -> Result<Request, ParseError> {
-        if buf.len() != 8 {
-            return Err(ParseError::InvalidLength);
-        }
-
+    /// Parses a USB control request from a byte array.
+    pub fn parse(buf: &[u8; 8]) -> Request {
         let rt = buf[0];
         let recipient = rt & 0b11111;
 
-        Ok(Request {
+        Request {
             direction: rt.into(),
             request_type: unsafe { mem::transmute((rt >> 5) & 0b11) },
             recipient: if recipient <= 3 {
@@ -124,7 +115,7 @@ impl Request {
             value: (buf[2] as u16) | ((buf[3] as u16) << 8),
             index: (buf[4] as u16) | ((buf[5] as u16) << 8),
             length: (buf[6] as u16) | ((buf[7] as u16) << 8),
-        })
+        }
     }
 
     /// Gets the descriptor type and index from the value field of a GET_DESCRIPTOR request.
diff --git a/embassy-usb/src/driver.rs b/embassy-usb/src/driver.rs
index a7b16efa5..1c6ba1f52 100644
--- a/embassy-usb/src/driver.rs
+++ b/embassy-usb/src/driver.rs
@@ -1,5 +1,7 @@
 use core::future::Future;
 
+use crate::control::Request;
+
 use super::types::*;
 
 /// Driver for a specific USB peripheral. Implement this to add support for a new hardware
@@ -7,6 +9,7 @@ use super::types::*;
 pub trait Driver<'a> {
     type EndpointOut: EndpointOut + 'a;
     type EndpointIn: EndpointIn + 'a;
+    type ControlPipe: ControlPipe + 'a;
     type Bus: Bus + 'a;
 
     /// Allocates an endpoint and specified endpoint parameters. This method is called by the device
@@ -36,6 +39,11 @@ pub trait Driver<'a> {
         interval: u8,
     ) -> Result<Self::EndpointIn, EndpointAllocError>;
 
+    fn alloc_control_pipe(
+        &mut self,
+        max_packet_size: u16,
+    ) -> Result<Self::ControlPipe, EndpointAllocError>;
+
     /// Enables and initializes the USB peripheral. Soon after enabling the device will be reset, so
     /// there is no need to perform a USB reset in this method.
     fn enable(self) -> Self::Bus;
@@ -122,6 +130,40 @@ pub trait EndpointOut: Endpoint {
     fn read<'a>(&'a mut self, buf: &'a mut [u8]) -> Self::ReadFuture<'a>;
 }
 
+pub trait ControlPipe {
+    type SetupFuture<'a>: Future<Output = Request> + 'a
+    where
+        Self: 'a;
+    type DataOutFuture<'a>: Future<Output = Result<usize, ReadError>> + 'a
+    where
+        Self: 'a;
+    type AcceptInFuture<'a>: Future<Output = ()> + 'a
+    where
+        Self: 'a;
+
+    /// Reads a single setup packet from the endpoint.
+    fn setup<'a>(&'a mut self) -> Self::SetupFuture<'a>;
+
+    /// Reads the data packet of a control write sequence.
+    ///
+    /// Must be called after `setup()` for requests with `direction` of `Out`
+    /// and `length` greater than zero.
+    ///
+    /// `buf.len()` must be greater than or equal to the request's `length`.
+    fn data_out<'a>(&'a mut self, buf: &'a mut [u8]) -> Self::DataOutFuture<'a>;
+
+    /// Accepts a control request.
+    fn accept(&mut self);
+
+    /// Accepts a control read request with `data`.
+    ///
+    /// `data.len()` must be less than or equal to the request's `length`.
+    fn accept_in<'a>(&'a mut self, data: &'a [u8]) -> Self::AcceptInFuture<'a>;
+
+    /// Rejects a control request.
+    fn reject(&mut self);
+}
+
 pub trait EndpointIn: Endpoint {
     type WriteFuture<'a>: Future<Output = Result<(), WriteError>> + 'a
     where
diff --git a/embassy-usb/src/lib.rs b/embassy-usb/src/lib.rs
index 95f78804d..4082868fb 100644
--- a/embassy-usb/src/lib.rs
+++ b/embassy-usb/src/lib.rs
@@ -1,16 +1,19 @@
 #![no_std]
 #![feature(generic_associated_types)]
+#![feature(type_alias_impl_trait)]
 
 // This mod MUST go first, so that the others see its macros.
 pub(crate) mod fmt;
 
 mod builder;
-mod control;
+pub mod class;
+pub mod control;
 pub mod descriptor;
 pub mod driver;
 pub mod types;
 mod util;
 
+use self::class::{RequestStatus, UsbClass};
 use self::control::*;
 use self::descriptor::*;
 use self::driver::*;
@@ -48,10 +51,9 @@ pub const CONFIGURATION_VALUE: u8 = 1;
 /// The default value for bAlternateSetting for all interfaces.
 pub const DEFAULT_ALTERNATE_SETTING: u8 = 0;
 
-pub struct UsbDevice<'d, D: Driver<'d>> {
+pub struct UsbDevice<'d, D: Driver<'d>, C: UsbClass<'d, D>> {
     bus: D::Bus,
-    control_in: D::EndpointIn,
-    control_out: D::EndpointOut,
+    control: D::ControlPipe,
 
     config: Config<'d>,
     device_descriptor: &'d [u8],
@@ -62,32 +64,21 @@ pub struct UsbDevice<'d, D: Driver<'d>> {
     remote_wakeup_enabled: bool,
     self_powered: bool,
     pending_address: u8,
+
+    classes: C,
 }
 
-impl<'d, D: Driver<'d>> UsbDevice<'d, D> {
+impl<'d, D: Driver<'d>, C: UsbClass<'d, D>> UsbDevice<'d, D, C> {
     pub(crate) fn build(
         mut driver: D,
         config: Config<'d>,
         device_descriptor: &'d [u8],
         config_descriptor: &'d [u8],
         bos_descriptor: &'d [u8],
+        classes: C,
     ) -> Self {
-        let control_out = driver
-            .alloc_endpoint_out(
-                Some(0x00.into()),
-                EndpointType::Control,
-                config.max_packet_size_0 as u16,
-                0,
-            )
-            .expect("failed to alloc control endpoint");
-
-        let control_in = driver
-            .alloc_endpoint_in(
-                Some(0x80.into()),
-                EndpointType::Control,
-                config.max_packet_size_0 as u16,
-                0,
-            )
+        let control = driver
+            .alloc_control_pipe(config.max_packet_size_0 as u16)
             .expect("failed to alloc control endpoint");
 
         // Enable the USB bus.
@@ -97,8 +88,7 @@ impl<'d, D: Driver<'d>> UsbDevice<'d, D> {
         Self {
             bus: driver,
             config,
-            control_in,
-            control_out,
+            control,
             device_descriptor,
             config_descriptor,
             bos_descriptor,
@@ -106,14 +96,13 @@ impl<'d, D: Driver<'d>> UsbDevice<'d, D> {
             remote_wakeup_enabled: false,
             self_powered: false,
             pending_address: 0,
+            classes,
         }
     }
 
     pub async fn run(&mut self) {
-        let mut buf = [0; 8];
-
         loop {
-            let control_fut = self.control_out.read(&mut buf);
+            let control_fut = self.control.setup();
             let bus_fut = self.bus.poll();
             match select(bus_fut, control_fut).await {
                 Either::Left(evt) => match evt {
@@ -124,11 +113,7 @@ impl<'d, D: Driver<'d>> UsbDevice<'d, D> {
                         self.remote_wakeup_enabled = false;
                         self.pending_address = 0;
 
-                        // TODO
-                        //self.control.reset();
-                        //for cls in classes {
-                        //    cls.reset();
-                        //}
+                        self.classes.reset();
                     }
                     Event::Resume => {}
                     Event::Suspend => {
@@ -136,16 +121,9 @@ impl<'d, D: Driver<'d>> UsbDevice<'d, D> {
                         self.device_state = UsbDeviceState::Suspend;
                     }
                 },
-                Either::Right(n) => {
-                    let n = n.unwrap();
-                    assert_eq!(n, 8);
-                    let req = Request::parse(&buf).unwrap();
+                Either::Right(req) => {
                     info!("control request: {:x}", req);
 
-                    // Now that we have properly parsed the setup packet, ensure the end-point is no longer in
-                    // a stalled state.
-                    self.control_out.set_stalled(false);
-
                     match req.direction {
                         UsbDirection::In => self.handle_control_in(req).await,
                         UsbDirection::Out => self.handle_control_out(req).await,
@@ -155,36 +133,6 @@ impl<'d, D: Driver<'d>> UsbDevice<'d, D> {
         }
     }
 
-    async fn write_chunked(&mut self, data: &[u8]) -> Result<(), driver::WriteError> {
-        for c in data.chunks(8) {
-            self.control_in.write(c).await?;
-        }
-        if data.len() % 8 == 0 {
-            self.control_in.write(&[]).await?;
-        }
-        Ok(())
-    }
-
-    async fn control_out_accept(&mut self, req: Request) {
-        info!("control out accept");
-        // status phase
-        // todo: cleanup
-        self.control_out.read(&mut []).await.unwrap();
-    }
-
-    async fn control_in_accept(&mut self, req: Request, data: &[u8]) {
-        info!("control accept {:x}", data);
-
-        let len = data.len().min(req.length as _);
-        if let Err(e) = self.write_chunked(&data[..len]).await {
-            info!("write_chunked failed: {:?}", e);
-        }
-
-        // status phase
-        // todo: cleanup
-        self.control_out.read(&mut []).await.unwrap();
-    }
-
     async fn control_in_accept_writer(
         &mut self,
         req: Request,
@@ -193,17 +141,26 @@ impl<'d, D: Driver<'d>> UsbDevice<'d, D> {
         let mut buf = [0; 256];
         let mut w = DescriptorWriter::new(&mut buf);
         f(&mut w);
-        let pos = w.position();
-        self.control_in_accept(req, &buf[..pos]).await;
-    }
-
-    fn control_reject(&mut self, req: Request) {
-        info!("control reject");
-        self.control_out.set_stalled(true);
+        let pos = w.position().min(usize::from(req.length));
+        self.control.accept_in(&buf[..pos]).await;
     }
 
     async fn handle_control_out(&mut self, req: Request) {
-        // TODO actually read the data if there's an OUT data phase.
+        {
+            let mut buf = [0; 128];
+            let data = if req.length > 0 {
+                let size = self.control.data_out(&mut buf).await.unwrap();
+                &buf[0..size]
+            } else {
+                &[]
+            };
+
+            match self.classes.control_out(req, data).await {
+                RequestStatus::Accepted => return self.control.accept(),
+                RequestStatus::Rejected => return self.control.reject(),
+                RequestStatus::Unhandled => (),
+            }
+        }
 
         const CONFIGURATION_NONE_U16: u16 = CONFIGURATION_NONE as u16;
         const CONFIGURATION_VALUE_U16: u16 = CONFIGURATION_VALUE as u16;
@@ -217,12 +174,12 @@ impl<'d, D: Driver<'d>> UsbDevice<'d, D> {
                     Request::FEATURE_DEVICE_REMOTE_WAKEUP,
                 ) => {
                     self.remote_wakeup_enabled = false;
-                    self.control_out_accept(req).await;
+                    self.control.accept();
                 }
 
                 (Recipient::Endpoint, Request::CLEAR_FEATURE, Request::FEATURE_ENDPOINT_HALT) => {
                     //self.bus.set_stalled(((req.index as u8) & 0x8f).into(), false);
-                    self.control_out_accept(req).await;
+                    self.control.accept();
                 }
 
                 (
@@ -231,51 +188,61 @@ impl<'d, D: Driver<'d>> UsbDevice<'d, D> {
                     Request::FEATURE_DEVICE_REMOTE_WAKEUP,
                 ) => {
                     self.remote_wakeup_enabled = true;
-                    self.control_out_accept(req).await;
+                    self.control.accept();
                 }
 
                 (Recipient::Endpoint, Request::SET_FEATURE, Request::FEATURE_ENDPOINT_HALT) => {
                     self.bus
                         .set_stalled(((req.index as u8) & 0x8f).into(), true);
-                    self.control_out_accept(req).await;
+                    self.control.accept();
                 }
 
                 (Recipient::Device, Request::SET_ADDRESS, 1..=127) => {
                     self.pending_address = req.value as u8;
 
                     // on NRF the hardware auto-handles SET_ADDRESS.
-                    self.control_out_accept(req).await;
+                    self.control.accept();
                 }
 
                 (Recipient::Device, Request::SET_CONFIGURATION, CONFIGURATION_VALUE_U16) => {
                     self.device_state = UsbDeviceState::Configured;
-                    self.control_out_accept(req).await;
+                    self.control.accept();
                 }
 
                 (Recipient::Device, Request::SET_CONFIGURATION, CONFIGURATION_NONE_U16) => {
                     match self.device_state {
                         UsbDeviceState::Default => {
-                            self.control_out_accept(req).await;
+                            self.control.accept();
                         }
                         _ => {
                             self.device_state = UsbDeviceState::Addressed;
-                            self.control_out_accept(req).await;
+                            self.control.accept();
                         }
                     }
                 }
 
                 (Recipient::Interface, Request::SET_INTERFACE, DEFAULT_ALTERNATE_SETTING_U16) => {
                     // TODO: do something when alternate settings are implemented
-                    self.control_out_accept(req).await;
+                    self.control.accept();
                 }
 
-                _ => self.control_reject(req),
+                _ => self.control.reject(),
             },
-            _ => self.control_reject(req),
+            _ => self.control.reject(),
         }
     }
 
     async fn handle_control_in(&mut self, req: Request) {
+        match self
+            .classes
+            .control_in(req, class::ControlIn::new(&mut self.control))
+            .await
+            .status()
+        {
+            RequestStatus::Accepted | RequestStatus::Rejected => return,
+            RequestStatus::Unhandled => (),
+        }
+
         match req.request_type {
             RequestType::Standard => match (req.recipient, req.request) {
                 (Recipient::Device, Request::GET_STATUS) => {
@@ -286,12 +253,12 @@ impl<'d, D: Driver<'d>> UsbDevice<'d, D> {
                     if self.remote_wakeup_enabled {
                         status |= 0x0002;
                     }
-                    self.control_in_accept(req, &status.to_le_bytes()).await;
+                    self.control.accept_in(&status.to_le_bytes()).await;
                 }
 
                 (Recipient::Interface, Request::GET_STATUS) => {
                     let status: u16 = 0x0000;
-                    self.control_in_accept(req, &status.to_le_bytes()).await;
+                    self.control.accept_in(&status.to_le_bytes()).await;
                 }
 
                 (Recipient::Endpoint, Request::GET_STATUS) => {
@@ -300,7 +267,7 @@ impl<'d, D: Driver<'d>> UsbDevice<'d, D> {
                     if self.bus.is_stalled(ep_addr) {
                         status |= 0x0001;
                     }
-                    self.control_in_accept(req, &status.to_le_bytes()).await;
+                    self.control.accept_in(&status.to_le_bytes()).await;
                 }
 
                 (Recipient::Device, Request::GET_DESCRIPTOR) => {
@@ -312,17 +279,17 @@ impl<'d, D: Driver<'d>> UsbDevice<'d, D> {
                         UsbDeviceState::Configured => CONFIGURATION_VALUE,
                         _ => CONFIGURATION_NONE,
                     };
-                    self.control_in_accept(req, &status.to_le_bytes()).await;
+                    self.control.accept_in(&status.to_le_bytes()).await;
                 }
 
                 (Recipient::Interface, Request::GET_INTERFACE) => {
                     // TODO: change when alternate settings are implemented
                     let status = DEFAULT_ALTERNATE_SETTING;
-                    self.control_in_accept(req, &status.to_le_bytes()).await;
+                    self.control.accept_in(&status.to_le_bytes()).await;
                 }
-                _ => self.control_reject(req),
+                _ => self.control.reject(),
             },
-            _ => self.control_reject(req),
+            _ => self.control.reject(),
         }
     }
 
@@ -331,11 +298,9 @@ impl<'d, D: Driver<'d>> UsbDevice<'d, D> {
         let config = self.config.clone();
 
         match dtype {
-            descriptor_type::BOS => self.control_in_accept(req, self.bos_descriptor).await,
-            descriptor_type::DEVICE => self.control_in_accept(req, self.device_descriptor).await,
-            descriptor_type::CONFIGURATION => {
-                self.control_in_accept(req, self.config_descriptor).await
-            }
+            descriptor_type::BOS => self.control.accept_in(self.bos_descriptor).await,
+            descriptor_type::DEVICE => self.control.accept_in(self.device_descriptor).await,
+            descriptor_type::CONFIGURATION => self.control.accept_in(self.config_descriptor).await,
             descriptor_type::STRING => {
                 if index == 0 {
                     self.control_in_accept_writer(req, |w| {
@@ -363,11 +328,11 @@ impl<'d, D: Driver<'d>> UsbDevice<'d, D> {
                         self.control_in_accept_writer(req, |w| w.string(s).unwrap())
                             .await;
                     } else {
-                        self.control_reject(req)
+                        self.control.reject()
                     }
                 }
             }
-            _ => self.control_reject(req),
+            _ => self.control.reject(),
         }
     }
 }