usb: unify ControlHandler+DeviceStateHandler, route all control requests to all handlers.

- Allows classes to handle vendor requests.
- Allows classes to use a single handler for multiple interfaces.
- Allows classes to access the other events (previously only `reset` was available).

3 files changed, 179 insertions, 124 deletions

diff --git a/embassy-usb/src/class/cdc_acm.rs b/embassy-usb/src/class/cdc_acm.rs
index fb9eaeca7..ff82ad40d 100644
--- a/embassy-usb/src/class/cdc_acm.rs
+++ b/embassy-usb/src/class/cdc_acm.rs
@@ -6,10 +6,10 @@ use core::sync::atomic::{AtomicBool, Ordering};
 
 use embassy_sync::blocking_mutex::CriticalSectionMutex;
 
-use crate::control::{self, ControlHandler, InResponse, OutResponse, Request};
+use crate::control::{self, InResponse, OutResponse, Recipient, Request, RequestType};
 use crate::driver::{Driver, Endpoint, EndpointError, EndpointIn, EndpointOut};
 use crate::types::*;
-use crate::Builder;
+use crate::{Builder, Handler};
 
 /// This should be used as `device_class` when building the `UsbDevice`.
 pub const USB_CLASS_CDC: u8 = 0x02;
@@ -67,6 +67,7 @@ pub struct CdcAcmClass<'d, D: Driver<'d>> {
 }
 
 struct Control<'a> {
+    comm_if: InterfaceNumber,
     shared: &'a ControlShared,
 }
 
@@ -98,7 +99,7 @@ impl<'a> Control<'a> {
     }
 }
 
-impl<'d> ControlHandler for Control<'d> {
+impl<'d> Handler for Control<'d> {
     fn reset(&mut self) {
         let shared = self.shared();
         shared.line_coding.lock(|x| x.set(LineCoding::default()));
@@ -106,12 +107,18 @@ impl<'d> ControlHandler for Control<'d> {
         shared.rts.store(false, Ordering::Relaxed);
     }
 
-    fn control_out(&mut self, req: control::Request, data: &[u8]) -> OutResponse {
+    fn control_out(&mut self, req: control::Request, data: &[u8]) -> Option<OutResponse> {
+        if (req.request_type, req.recipient, req.index)
+            != (RequestType::Class, Recipient::Interface, self.comm_if.0 as u16)
+        {
+            return None;
+        }
+
         match req.request {
             REQ_SEND_ENCAPSULATED_COMMAND => {
                 // We don't actually support encapsulated commands but pretend we do for standards
                 // compatibility.
-                OutResponse::Accepted
+                Some(OutResponse::Accepted)
             }
             REQ_SET_LINE_CODING if data.len() >= 7 => {
                 let coding = LineCoding {
@@ -123,7 +130,7 @@ impl<'d> ControlHandler for Control<'d> {
                 self.shared().line_coding.lock(|x| x.set(coding));
                 debug!("Set line coding to: {:?}", coding);
 
-                OutResponse::Accepted
+                Some(OutResponse::Accepted)
             }
             REQ_SET_CONTROL_LINE_STATE => {
                 let dtr = (req.value & 0x0001) != 0;
@@ -134,13 +141,19 @@ impl<'d> ControlHandler for Control<'d> {
                 shared.rts.store(rts, Ordering::Relaxed);
                 debug!("Set dtr {}, rts {}", dtr, rts);
 
-                OutResponse::Accepted
+                Some(OutResponse::Accepted)
             }
-            _ => OutResponse::Rejected,
+            _ => Some(OutResponse::Rejected),
         }
     }
 
-    fn control_in<'a>(&'a mut self, req: Request, buf: &'a mut [u8]) -> InResponse<'a> {
+    fn control_in<'a>(&'a mut self, req: Request, buf: &'a mut [u8]) -> Option<InResponse<'a>> {
+        if (req.request_type, req.recipient, req.index)
+            != (RequestType::Class, Recipient::Interface, self.comm_if.0 as u16)
+        {
+            return None;
+        }
+
         match req.request {
             // REQ_GET_ENCAPSULATED_COMMAND is not really supported - it will be rejected below.
             REQ_GET_LINE_CODING if req.length == 7 => {
@@ -151,9 +164,9 @@ impl<'d> ControlHandler for Control<'d> {
                 buf[4] = coding.stop_bits as u8;
                 buf[5] = coding.parity_type as u8;
                 buf[6] = coding.data_bits;
-                InResponse::Accepted(&buf[0..7])
+                Some(InResponse::Accepted(&buf[0..7]))
             }
-            _ => InResponse::Rejected,
+            _ => Some(InResponse::Rejected),
         }
     }
 }
@@ -162,17 +175,12 @@ impl<'d, D: Driver<'d>> CdcAcmClass<'d, D> {
     /// 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(builder: &mut Builder<'d, D>, state: &'d mut State<'d>, max_packet_size: u16) -> Self {
-        let control = state.control.write(Control { shared: &state.shared });
-
-        let control_shared = &state.shared;
-
         assert!(builder.control_buf_len() >= 7);
 
         let mut func = builder.function(USB_CLASS_CDC, CDC_SUBCLASS_ACM, CDC_PROTOCOL_NONE);
 
         // Control interface
         let mut iface = func.interface();
-        iface.handler(control);
         let comm_if = iface.interface_number();
         let data_if = u8::from(comm_if) + 1;
         let mut alt = iface.alt_setting(USB_CLASS_CDC, CDC_SUBCLASS_ACM, CDC_PROTOCOL_NONE, None);
@@ -213,6 +221,16 @@ impl<'d, D: Driver<'d>> CdcAcmClass<'d, D> {
         let read_ep = alt.endpoint_bulk_out(max_packet_size);
         let write_ep = alt.endpoint_bulk_in(max_packet_size);
 
+        drop(func);
+
+        let control = state.control.write(Control {
+            shared: &state.shared,
+            comm_if,
+        });
+        builder.handler(control);
+
+        let control_shared = &state.shared;
+
         CdcAcmClass {
             _comm_ep: comm_ep,
             _data_if: data_if,
diff --git a/embassy-usb/src/class/cdc_ncm/mod.rs b/embassy-usb/src/class/cdc_ncm/mod.rs
index d6c7d37e6..262499ccb 100644
--- a/embassy-usb/src/class/cdc_ncm/mod.rs
+++ b/embassy-usb/src/class/cdc_ncm/mod.rs
@@ -17,10 +17,10 @@
 use core::intrinsics::copy_nonoverlapping;
 use core::mem::{size_of, MaybeUninit};
 
-use crate::control::{self, ControlHandler, InResponse, OutResponse, Request};
+use crate::control::{self, InResponse, OutResponse, Recipient, Request, RequestType};
 use crate::driver::{Driver, Endpoint, EndpointError, EndpointIn, EndpointOut};
 use crate::types::*;
-use crate::Builder;
+use crate::{Builder, Handler};
 
 pub mod embassy_net;
 
@@ -117,8 +117,7 @@ fn byteify<T>(buf: &mut [u8], data: T) -> &[u8] {
 
 /// Internal state for the CDC-NCM class.
 pub struct State<'a> {
-    comm_control: MaybeUninit<CommControl<'a>>,
-    data_control: MaybeUninit<DataControl>,
+    control: MaybeUninit<Control<'a>>,
     shared: ControlShared,
 }
 
@@ -126,8 +125,7 @@ impl<'a> State<'a> {
     /// Create a new `State`.
     pub fn new() -> Self {
         Self {
-            comm_control: MaybeUninit::uninit(),
-            data_control: MaybeUninit::uninit(),
+            control: MaybeUninit::uninit(),
             shared: Default::default(),
         }
     }
@@ -144,29 +142,55 @@ impl Default for ControlShared {
     }
 }
 
-struct CommControl<'a> {
+struct Control<'a> {
     mac_addr_string: StringIndex,
     shared: &'a ControlShared,
     mac_addr_str: [u8; 12],
+    comm_if: InterfaceNumber,
+    data_if: InterfaceNumber,
 }
 
-impl<'d> ControlHandler for CommControl<'d> {
-    fn control_out(&mut self, req: control::Request, _data: &[u8]) -> OutResponse {
+impl<'d> Handler for Control<'d> {
+    fn set_alternate_setting(&mut self, iface: InterfaceNumber, alternate_setting: u8) {
+        if iface != self.data_if {
+            return;
+        }
+
+        match alternate_setting {
+            ALTERNATE_SETTING_ENABLED => info!("ncm: interface enabled"),
+            ALTERNATE_SETTING_DISABLED => info!("ncm: interface disabled"),
+            _ => unreachable!(),
+        }
+    }
+
+    fn control_out(&mut self, req: control::Request, _data: &[u8]) -> Option<OutResponse> {
+        if (req.request_type, req.recipient, req.index)
+            != (RequestType::Class, Recipient::Interface, self.comm_if.0 as u16)
+        {
+            return None;
+        }
+
         match req.request {
             REQ_SEND_ENCAPSULATED_COMMAND => {
                 // We don't actually support encapsulated commands but pretend we do for standards
                 // compatibility.
-                OutResponse::Accepted
+                Some(OutResponse::Accepted)
             }
             REQ_SET_NTB_INPUT_SIZE => {
                 // TODO
-                OutResponse::Accepted
+                Some(OutResponse::Accepted)
             }
-            _ => OutResponse::Rejected,
+            _ => Some(OutResponse::Rejected),
         }
     }
 
-    fn control_in<'a>(&'a mut self, req: Request, buf: &'a mut [u8]) -> InResponse<'a> {
+    fn control_in<'a>(&'a mut self, req: Request, buf: &'a mut [u8]) -> Option<InResponse<'a>> {
+        if (req.request_type, req.recipient, req.index)
+            != (RequestType::Class, Recipient::Interface, self.comm_if.0 as u16)
+        {
+            return None;
+        }
+
         match req.request {
             REQ_GET_NTB_PARAMETERS => {
                 let res = NtbParameters {
@@ -187,9 +211,9 @@ impl<'d> ControlHandler for CommControl<'d> {
                         max_datagram_count: 1, // We only decode 1 packet per NTB
                     },
                 };
-                InResponse::Accepted(byteify(buf, res))
+                Some(InResponse::Accepted(byteify(buf, res)))
             }
-            _ => InResponse::Rejected,
+            _ => Some(InResponse::Rejected),
         }
     }
 
@@ -214,18 +238,6 @@ impl<'d> ControlHandler for CommControl<'d> {
     }
 }
 
-struct DataControl {}
-
-impl ControlHandler for DataControl {
-    fn set_alternate_setting(&mut self, alternate_setting: u8) {
-        match alternate_setting {
-            ALTERNATE_SETTING_ENABLED => info!("ncm: interface enabled"),
-            ALTERNATE_SETTING_DISABLED => info!("ncm: interface disabled"),
-            _ => unreachable!(),
-        }
-    }
-}
-
 /// CDC-NCM class
 pub struct CdcNcmClass<'d, D: Driver<'d>> {
     _comm_if: InterfaceNumber,
@@ -253,11 +265,6 @@ impl<'d, D: Driver<'d>> CdcNcmClass<'d, D> {
         // Control interface
         let mut iface = func.interface();
         let mac_addr_string = iface.string();
-        iface.handler(state.comm_control.write(CommControl {
-            mac_addr_string,
-            shared: &state.shared,
-            mac_addr_str: [0; 12],
-        }));
         let comm_if = iface.interface_number();
         let mut alt = iface.alt_setting(USB_CLASS_CDC, CDC_SUBCLASS_NCM, CDC_PROTOCOL_NONE, None);
 
@@ -307,13 +314,23 @@ impl<'d, D: Driver<'d>> CdcNcmClass<'d, D> {
 
         // Data interface
         let mut iface = func.interface();
-        iface.handler(state.data_control.write(DataControl {}));
         let data_if = iface.interface_number();
         let _alt = iface.alt_setting(USB_CLASS_CDC_DATA, 0x00, CDC_PROTOCOL_NTB, None);
         let mut alt = iface.alt_setting(USB_CLASS_CDC_DATA, 0x00, CDC_PROTOCOL_NTB, None);
         let read_ep = alt.endpoint_bulk_out(max_packet_size);
         let write_ep = alt.endpoint_bulk_in(max_packet_size);
 
+        drop(func);
+
+        let control = state.control.write(Control {
+            mac_addr_string,
+            shared: &state.shared,
+            mac_addr_str: [0; 12],
+            comm_if,
+            data_if,
+        });
+        builder.handler(control);
+
         CdcNcmClass {
             _comm_if: comm_if,
             comm_ep,
diff --git a/embassy-usb/src/class/hid.rs b/embassy-usb/src/class/hid.rs
index 0283c1124..974268c62 100644
--- a/embassy-usb/src/class/hid.rs
+++ b/embassy-usb/src/class/hid.rs
@@ -9,9 +9,10 @@ use ssmarshal::serialize;
 #[cfg(feature = "usbd-hid")]
 use usbd_hid::descriptor::AsInputReport;
 
-use crate::control::{ControlHandler, InResponse, OutResponse, Request, RequestType};
+use crate::control::{InResponse, OutResponse, Recipient, Request, RequestType};
 use crate::driver::{Driver, Endpoint, EndpointError, EndpointIn, EndpointOut};
-use crate::Builder;
+use crate::types::InterfaceNumber;
+use crate::{Builder, Handler};
 
 const USB_CLASS_HID: u8 = 0x03;
 const USB_SUBCLASS_NONE: u8 = 0x00;
@@ -100,17 +101,11 @@ fn build<'d, D: Driver<'d>>(
     config: Config<'d>,
     with_out_endpoint: bool,
 ) -> (Option<D::EndpointOut>, D::EndpointIn, &'d AtomicUsize) {
-    let control = state.control.write(Control::new(
-        config.report_descriptor,
-        config.request_handler,
-        &state.out_report_offset,
-    ));
-
     let len = config.report_descriptor.len();
 
     let mut func = builder.function(USB_CLASS_HID, USB_SUBCLASS_NONE, USB_PROTOCOL_NONE);
     let mut iface = func.interface();
-    iface.handler(control);
+    let if_num = iface.interface_number();
     let mut alt = iface.alt_setting(USB_CLASS_HID, USB_SUBCLASS_NONE, USB_PROTOCOL_NONE, None);
 
     // HID descriptor
@@ -139,6 +134,16 @@ fn build<'d, D: Driver<'d>>(
         None
     };
 
+    drop(func);
+
+    let control = state.control.write(Control::new(
+        if_num,
+        config.report_descriptor,
+        config.request_handler,
+        &state.out_report_offset,
+    ));
+    builder.handler(control);
+
     (ep_out, ep_in, &state.out_report_offset)
 }
 
@@ -400,6 +405,7 @@ pub trait RequestHandler {
 }
 
 struct Control<'d> {
+    if_num: InterfaceNumber,
     report_descriptor: &'d [u8],
     request_handler: Option<&'d dyn RequestHandler>,
     out_report_offset: &'d AtomicUsize,
@@ -408,11 +414,13 @@ struct Control<'d> {
 
 impl<'d> Control<'d> {
     fn new(
+        if_num: InterfaceNumber,
         report_descriptor: &'d [u8],
         request_handler: Option<&'d dyn RequestHandler>,
         out_report_offset: &'d AtomicUsize,
     ) -> Self {
         Control {
+            if_num,
             report_descriptor,
             request_handler,
             out_report_offset,
@@ -438,88 +446,100 @@ impl<'d> Control<'d> {
     }
 }
 
-impl<'d> ControlHandler for Control<'d> {
+impl<'d> Handler for Control<'d> {
     fn reset(&mut self) {
         self.out_report_offset.store(0, Ordering::Release);
     }
 
-    fn get_descriptor<'a>(&'a mut self, req: Request, _buf: &'a mut [u8]) -> InResponse<'a> {
-        match (req.value >> 8) as u8 {
-            HID_DESC_DESCTYPE_HID_REPORT => InResponse::Accepted(self.report_descriptor),
-            HID_DESC_DESCTYPE_HID => InResponse::Accepted(&self.hid_descriptor),
-            _ => InResponse::Rejected,
+    fn control_out(&mut self, req: Request, data: &[u8]) -> Option<OutResponse> {
+        if (req.request_type, req.recipient, req.index)
+            != (RequestType::Class, Recipient::Interface, self.if_num.0 as u16)
+        {
+            return None;
         }
-    }
 
-    fn control_out(&mut self, req: Request, data: &[u8]) -> OutResponse {
         trace!("HID control_out {:?} {=[u8]:x}", req, data);
-        if let RequestType::Class = req.request_type {
-            match req.request {
-                HID_REQ_SET_IDLE => {
-                    if let Some(handler) = self.request_handler {
-                        let id = req.value as u8;
-                        let id = (id != 0).then(|| ReportId::In(id));
-                        let dur = u32::from(req.value >> 8);
-                        let dur = if dur == 0 { u32::MAX } else { 4 * dur };
-                        handler.set_idle_ms(id, dur);
-                    }
-                    OutResponse::Accepted
+        match req.request {
+            HID_REQ_SET_IDLE => {
+                if let Some(handler) = self.request_handler {
+                    let id = req.value as u8;
+                    let id = (id != 0).then(|| ReportId::In(id));
+                    let dur = u32::from(req.value >> 8);
+                    let dur = if dur == 0 { u32::MAX } else { 4 * dur };
+                    handler.set_idle_ms(id, dur);
                 }
-                HID_REQ_SET_REPORT => match (ReportId::try_from(req.value), self.request_handler) {
-                    (Ok(id), Some(handler)) => handler.set_report(id, data),
-                    _ => OutResponse::Rejected,
-                },
-                HID_REQ_SET_PROTOCOL => {
-                    if req.value == 1 {
-                        OutResponse::Accepted
-                    } else {
-                        warn!("HID Boot Protocol is unsupported.");
-                        OutResponse::Rejected // UNSUPPORTED: Boot Protocol
-                    }
+                Some(OutResponse::Accepted)
+            }
+            HID_REQ_SET_REPORT => match (ReportId::try_from(req.value), self.request_handler) {
+                (Ok(id), Some(handler)) => Some(handler.set_report(id, data)),
+                _ => Some(OutResponse::Rejected),
+            },
+            HID_REQ_SET_PROTOCOL => {
+                if req.value == 1 {
+                    Some(OutResponse::Accepted)
+                } else {
+                    warn!("HID Boot Protocol is unsupported.");
+                    Some(OutResponse::Rejected) // UNSUPPORTED: Boot Protocol
                 }
-                _ => OutResponse::Rejected,
             }
-        } else {
-            OutResponse::Rejected // UNSUPPORTED: SET_DESCRIPTOR
+            _ => Some(OutResponse::Rejected),
         }
     }
 
-    fn control_in<'a>(&'a mut self, req: Request, buf: &'a mut [u8]) -> InResponse<'a> {
-        trace!("HID control_in {:?}", req);
-        match req.request {
-            HID_REQ_GET_REPORT => {
-                let size = match ReportId::try_from(req.value) {
-                    Ok(id) => self.request_handler.and_then(|x| x.get_report(id, buf)),
-                    Err(_) => None,
-                };
-
-                if let Some(size) = size {
-                    InResponse::Accepted(&buf[0..size])
-                } else {
-                    InResponse::Rejected
-                }
-            }
-            HID_REQ_GET_IDLE => {
-                if let Some(handler) = self.request_handler {
-                    let id = req.value as u8;
-                    let id = (id != 0).then(|| ReportId::In(id));
-                    if let Some(dur) = handler.get_idle_ms(id) {
-                        let dur = u8::try_from(dur / 4).unwrap_or(0);
-                        buf[0] = dur;
-                        InResponse::Accepted(&buf[0..1])
-                    } else {
-                        InResponse::Rejected
+    fn control_in<'a>(&'a mut self, req: Request, buf: &'a mut [u8]) -> Option<InResponse<'a>> {
+        if req.index != self.if_num.0 as u16 {
+            return None;
+        }
+
+        match (req.request_type, req.recipient) {
+            (RequestType::Standard, Recipient::Interface) => match req.request {
+                Request::GET_DESCRIPTOR => match (req.value >> 8) as u8 {
+                    HID_DESC_DESCTYPE_HID_REPORT => Some(InResponse::Accepted(self.report_descriptor)),
+                    HID_DESC_DESCTYPE_HID => Some(InResponse::Accepted(&self.hid_descriptor)),
+                    _ => Some(InResponse::Rejected),
+                },
+
+                _ => Some(InResponse::Rejected),
+            },
+            (RequestType::Class, Recipient::Interface) => {
+                trace!("HID control_in {:?}", req);
+                match req.request {
+                    HID_REQ_GET_REPORT => {
+                        let size = match ReportId::try_from(req.value) {
+                            Ok(id) => self.request_handler.and_then(|x| x.get_report(id, buf)),
+                            Err(_) => None,
+                        };
+
+                        if let Some(size) = size {
+                            Some(InResponse::Accepted(&buf[0..size]))
+                        } else {
+                            Some(InResponse::Rejected)
+                        }
                     }
-                } else {
-                    InResponse::Rejected
+                    HID_REQ_GET_IDLE => {
+                        if let Some(handler) = self.request_handler {
+                            let id = req.value as u8;
+                            let id = (id != 0).then(|| ReportId::In(id));
+                            if let Some(dur) = handler.get_idle_ms(id) {
+                                let dur = u8::try_from(dur / 4).unwrap_or(0);
+                                buf[0] = dur;
+                                Some(InResponse::Accepted(&buf[0..1]))
+                            } else {
+                                Some(InResponse::Rejected)
+                            }
+                        } else {
+                            Some(InResponse::Rejected)
+                        }
+                    }
+                    HID_REQ_GET_PROTOCOL => {
+                        // UNSUPPORTED: Boot Protocol
+                        buf[0] = 1;
+                        Some(InResponse::Accepted(&buf[0..1]))
+                    }
+                    _ => Some(InResponse::Rejected),
                 }
             }
-            HID_REQ_GET_PROTOCOL => {
-                // UNSUPPORTED: Boot Protocol
-                buf[0] = 1;
-                InResponse::Accepted(&buf[0..1])
-            }
-            _ => InResponse::Rejected,
+            _ => None,
         }
     }
 }