689 lines
26 KiB
Rust
689 lines
26 KiB
Rust
#![no_std]
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#![feature(type_alias_impl_trait)]
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// This mod MUST go first, so that the others see its macros.
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pub(crate) mod fmt;
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pub use embassy_usb_driver as driver;
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mod builder;
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pub mod class;
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pub mod control;
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pub mod descriptor;
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mod descriptor_reader;
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pub mod types;
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use embassy_futures::select::{select, Either};
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use heapless::Vec;
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pub use crate::builder::{Builder, Config};
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use crate::control::*;
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use crate::descriptor::*;
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use crate::descriptor_reader::foreach_endpoint;
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use crate::driver::{Bus, ControlPipe, Direction, Driver, EndpointAddress, Event};
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use crate::types::*;
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/// The global state of the USB device.
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///
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/// In general class traffic is only possible in the `Configured` state.
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#[repr(u8)]
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#[derive(PartialEq, Eq, Copy, Clone, Debug)]
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#[cfg_attr(feature = "defmt", derive(defmt::Format))]
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pub enum UsbDeviceState {
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/// The USB device has no power.
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Unpowered,
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/// The USB device is disabled.
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Disabled,
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/// The USB device has just been enabled or reset.
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Default,
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/// The USB device has received an address from the host.
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Addressed,
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/// The USB device has been configured and is fully functional.
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Configured,
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}
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#[derive(PartialEq, Eq, Copy, Clone, Debug)]
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#[cfg_attr(feature = "defmt", derive(defmt::Format))]
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pub enum RemoteWakeupError {
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InvalidState,
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Unsupported,
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}
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impl From<driver::Unsupported> for RemoteWakeupError {
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fn from(_: driver::Unsupported) -> Self {
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RemoteWakeupError::Unsupported
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}
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}
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/// The bConfiguration value for the not configured state.
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pub const CONFIGURATION_NONE: u8 = 0;
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/// The bConfiguration value for the single configuration supported by this device.
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pub const CONFIGURATION_VALUE: u8 = 1;
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pub const MAX_INTERFACE_COUNT: usize = 4;
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const STRING_INDEX_MANUFACTURER: u8 = 1;
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const STRING_INDEX_PRODUCT: u8 = 2;
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const STRING_INDEX_SERIAL_NUMBER: u8 = 3;
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const STRING_INDEX_CUSTOM_START: u8 = 4;
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/// A handler trait for changes in the device state of the [UsbDevice].
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pub trait DeviceStateHandler {
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/// Called when the USB device has been enabled or disabled.
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fn enabled(&self, _enabled: bool) {}
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/// Called when the host resets the device.
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fn reset(&self) {}
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/// Called when the host has set the address of the device to `addr`.
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fn addressed(&self, _addr: u8) {}
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/// Called when the host has enabled or disabled the configuration of the device.
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fn configured(&self, _configured: bool) {}
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/// Called when the bus has entered or exited the suspend state.
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fn suspended(&self, _suspended: bool) {}
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/// Called when remote wakeup feature is enabled or disabled.
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fn remote_wakeup_enabled(&self, _enabled: bool) {}
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}
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struct Interface<'d> {
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handler: Option<&'d mut dyn ControlHandler>,
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current_alt_setting: u8,
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num_alt_settings: u8,
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num_strings: u8,
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}
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pub struct UsbDevice<'d, D: Driver<'d>> {
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control_buf: &'d mut [u8],
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control: D::ControlPipe,
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inner: Inner<'d, D>,
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}
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struct Inner<'d, D: Driver<'d>> {
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bus: D::Bus,
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handler: Option<&'d dyn DeviceStateHandler>,
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config: Config<'d>,
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device_descriptor: &'d [u8],
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config_descriptor: &'d [u8],
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bos_descriptor: &'d [u8],
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device_state: UsbDeviceState,
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suspended: bool,
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remote_wakeup_enabled: bool,
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self_powered: bool,
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/// Our device address, or 0 if none.
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address: u8,
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/// SET_ADDRESS requests have special handling depending on the driver.
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/// This flag indicates that requests must be handled by `ControlPipe::accept_set_address()`
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/// instead of regular `accept()`.
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set_address_pending: bool,
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interfaces: Vec<Interface<'d>, MAX_INTERFACE_COUNT>,
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}
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impl<'d, D: Driver<'d>> UsbDevice<'d, D> {
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pub(crate) fn build(
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driver: D,
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config: Config<'d>,
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handler: Option<&'d dyn DeviceStateHandler>,
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device_descriptor: &'d [u8],
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config_descriptor: &'d [u8],
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bos_descriptor: &'d [u8],
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interfaces: Vec<Interface<'d>, MAX_INTERFACE_COUNT>,
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control_buf: &'d mut [u8],
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) -> UsbDevice<'d, D> {
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// Start the USB bus.
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// This prevent further allocation by consuming the driver.
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let (bus, control) = driver.start(config.max_packet_size_0 as u16);
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Self {
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control_buf,
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control,
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inner: Inner {
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bus,
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config,
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handler,
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device_descriptor,
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config_descriptor,
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bos_descriptor,
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device_state: UsbDeviceState::Unpowered,
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suspended: false,
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remote_wakeup_enabled: false,
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self_powered: false,
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address: 0,
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set_address_pending: false,
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interfaces,
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},
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}
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}
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/// Runs the `UsbDevice` forever.
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///
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/// This future may leave the bus in an invalid state if it is dropped.
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/// After dropping the future, [`UsbDevice::disable()`] should be called
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/// before calling any other `UsbDevice` methods to fully reset the
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/// peripheral.
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pub async fn run(&mut self) -> ! {
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loop {
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self.run_until_suspend().await;
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self.wait_resume().await;
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}
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}
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/// Runs the `UsbDevice` until the bus is suspended.
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///
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/// This future may leave the bus in an invalid state if it is dropped.
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/// After dropping the future, [`UsbDevice::disable()`] should be called
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/// before calling any other `UsbDevice` methods to fully reset the
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/// peripheral.
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pub async fn run_until_suspend(&mut self) -> () {
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while !self.inner.suspended {
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let control_fut = self.control.setup();
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let bus_fut = self.inner.bus.poll();
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match select(bus_fut, control_fut).await {
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Either::First(evt) => self.inner.handle_bus_event(evt).await,
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Either::Second(req) => self.handle_control(req).await,
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}
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}
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}
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/// Disables the USB peripheral.
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pub async fn disable(&mut self) {
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if self.inner.device_state != UsbDeviceState::Disabled {
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self.inner.bus.disable().await;
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self.inner.device_state = UsbDeviceState::Disabled;
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self.inner.suspended = false;
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self.inner.remote_wakeup_enabled = false;
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if let Some(h) = &self.inner.handler {
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h.enabled(false);
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}
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}
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}
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/// Waits for a resume condition on the USB bus.
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///
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/// This future is cancel-safe.
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pub async fn wait_resume(&mut self) {
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while self.inner.suspended {
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let evt = self.inner.bus.poll().await;
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self.inner.handle_bus_event(evt).await;
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}
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}
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/// Initiates a device remote wakeup on the USB bus.
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///
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/// If the bus is not suspended or remote wakeup is not enabled, an error
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/// will be returned.
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///
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/// This future may leave the bus in an inconsistent state if dropped.
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/// After dropping the future, [`UsbDevice::disable()`] should be called
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/// before calling any other `UsbDevice` methods to fully reset the peripheral.
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pub async fn remote_wakeup(&mut self) -> Result<(), RemoteWakeupError> {
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if self.inner.suspended && self.inner.remote_wakeup_enabled {
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self.inner.bus.remote_wakeup().await?;
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self.inner.suspended = false;
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if let Some(h) = &self.inner.handler {
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h.suspended(false);
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}
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Ok(())
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} else {
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Err(RemoteWakeupError::InvalidState)
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}
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}
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async fn handle_control(&mut self, req: [u8; 8]) {
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let req = Request::parse(&req);
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trace!("control request: {:?}", req);
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match req.direction {
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Direction::In => self.handle_control_in(req).await,
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Direction::Out => self.handle_control_out(req).await,
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}
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}
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async fn handle_control_in(&mut self, req: Request) {
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let mut resp_length = req.length as usize;
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let max_packet_size = self.control.max_packet_size();
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// If we don't have an address yet, respond with max 1 packet.
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// The host doesn't know our EP0 max packet size yet, and might assume
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// a full-length packet is a short packet, thinking we're done sending data.
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// See https://github.com/hathach/tinyusb/issues/184
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const DEVICE_DESCRIPTOR_LEN: usize = 18;
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if self.inner.address == 0
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&& max_packet_size < DEVICE_DESCRIPTOR_LEN
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&& (max_packet_size as usize) < resp_length
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{
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trace!("received control req while not addressed: capping response to 1 packet.");
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resp_length = max_packet_size;
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}
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match self.inner.handle_control_in(req, &mut self.control_buf) {
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InResponse::Accepted(data) => {
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let len = data.len().min(resp_length);
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let need_zlp = len != resp_length && (len % usize::from(max_packet_size)) == 0;
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let chunks = data[0..len]
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.chunks(max_packet_size)
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.chain(need_zlp.then(|| -> &[u8] { &[] }));
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for (first, last, chunk) in first_last(chunks) {
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match self.control.data_in(chunk, first, last).await {
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Ok(()) => {}
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Err(e) => {
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warn!("control accept_in failed: {:?}", e);
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return;
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}
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}
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}
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}
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InResponse::Rejected => self.control.reject().await,
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}
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}
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async fn handle_control_out(&mut self, req: Request) {
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let req_length = req.length as usize;
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let max_packet_size = self.control.max_packet_size();
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let mut total = 0;
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let chunks = self.control_buf[..req_length].chunks_mut(max_packet_size);
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for (first, last, chunk) in first_last(chunks) {
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let size = match self.control.data_out(chunk, first, last).await {
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Ok(x) => x,
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Err(e) => {
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warn!("usb: failed to read CONTROL OUT data stage: {:?}", e);
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return;
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}
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};
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total += size;
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if size < max_packet_size || total == req_length {
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break;
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}
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}
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let data = &self.control_buf[0..total];
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#[cfg(feature = "defmt")]
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trace!(" control out data: {:02x}", data);
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#[cfg(not(feature = "defmt"))]
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trace!(" control out data: {:02x?}", data);
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match self.inner.handle_control_out(req, data) {
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OutResponse::Accepted => {
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if self.inner.set_address_pending {
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self.control.accept_set_address(self.inner.address).await;
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self.inner.set_address_pending = false;
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} else {
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self.control.accept().await
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}
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}
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OutResponse::Rejected => self.control.reject().await,
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}
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}
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}
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impl<'d, D: Driver<'d>> Inner<'d, D> {
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async fn handle_bus_event(&mut self, evt: Event) {
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match evt {
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Event::Reset => {
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trace!("usb: reset");
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self.device_state = UsbDeviceState::Default;
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self.suspended = false;
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self.remote_wakeup_enabled = false;
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self.address = 0;
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for iface in self.interfaces.iter_mut() {
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iface.current_alt_setting = 0;
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if let Some(h) = &mut iface.handler {
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h.reset();
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h.set_alternate_setting(0);
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}
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}
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if let Some(h) = &self.handler {
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h.reset();
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}
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}
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Event::Resume => {
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trace!("usb: resume");
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self.suspended = false;
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if let Some(h) = &self.handler {
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h.suspended(false);
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}
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}
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Event::Suspend => {
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trace!("usb: suspend");
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self.suspended = true;
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if let Some(h) = &self.handler {
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h.suspended(true);
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}
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}
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Event::PowerDetected => {
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trace!("usb: power detected");
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self.bus.enable().await;
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self.device_state = UsbDeviceState::Default;
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if let Some(h) = &self.handler {
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h.enabled(true);
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}
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}
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Event::PowerRemoved => {
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trace!("usb: power removed");
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self.bus.disable().await;
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self.device_state = UsbDeviceState::Unpowered;
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if let Some(h) = &self.handler {
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h.enabled(false);
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}
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}
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}
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}
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fn handle_control_out(&mut self, req: Request, data: &[u8]) -> OutResponse {
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const CONFIGURATION_NONE_U16: u16 = CONFIGURATION_NONE as u16;
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const CONFIGURATION_VALUE_U16: u16 = CONFIGURATION_VALUE as u16;
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match (req.request_type, req.recipient) {
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(RequestType::Standard, Recipient::Device) => match (req.request, req.value) {
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(Request::CLEAR_FEATURE, Request::FEATURE_DEVICE_REMOTE_WAKEUP) => {
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self.remote_wakeup_enabled = false;
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if let Some(h) = &self.handler {
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h.remote_wakeup_enabled(false);
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}
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OutResponse::Accepted
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}
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(Request::SET_FEATURE, Request::FEATURE_DEVICE_REMOTE_WAKEUP) => {
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self.remote_wakeup_enabled = true;
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if let Some(h) = &self.handler {
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h.remote_wakeup_enabled(true);
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}
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OutResponse::Accepted
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}
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(Request::SET_ADDRESS, addr @ 1..=127) => {
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self.address = addr as u8;
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self.set_address_pending = true;
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self.device_state = UsbDeviceState::Addressed;
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if let Some(h) = &self.handler {
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h.addressed(self.address);
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}
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OutResponse::Accepted
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}
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(Request::SET_CONFIGURATION, CONFIGURATION_VALUE_U16) => {
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debug!("SET_CONFIGURATION: configured");
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self.device_state = UsbDeviceState::Configured;
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// Enable all endpoints of selected alt settings.
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foreach_endpoint(self.config_descriptor, |ep| {
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let iface = &self.interfaces[ep.interface as usize];
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self.bus
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.endpoint_set_enabled(ep.ep_address, iface.current_alt_setting == ep.interface_alt);
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})
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.unwrap();
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// Notify handler.
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if let Some(h) = &self.handler {
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h.configured(true);
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}
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OutResponse::Accepted
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}
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(Request::SET_CONFIGURATION, CONFIGURATION_NONE_U16) => match self.device_state {
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UsbDeviceState::Default => OutResponse::Accepted,
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_ => {
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debug!("SET_CONFIGURATION: unconfigured");
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self.device_state = UsbDeviceState::Addressed;
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// Disable all endpoints.
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foreach_endpoint(self.config_descriptor, |ep| {
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self.bus.endpoint_set_enabled(ep.ep_address, false);
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})
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.unwrap();
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// Notify handler.
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if let Some(h) = &self.handler {
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h.configured(false);
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}
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OutResponse::Accepted
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}
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},
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_ => OutResponse::Rejected,
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},
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(RequestType::Standard, Recipient::Interface) => {
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let iface = match self.interfaces.get_mut(req.index as usize) {
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Some(iface) => iface,
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None => return OutResponse::Rejected,
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};
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match req.request {
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Request::SET_INTERFACE => {
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let new_altsetting = req.value as u8;
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if new_altsetting >= iface.num_alt_settings {
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warn!("SET_INTERFACE: trying to select alt setting out of range.");
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return OutResponse::Rejected;
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}
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iface.current_alt_setting = new_altsetting;
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// Enable/disable EPs of this interface as needed.
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foreach_endpoint(self.config_descriptor, |ep| {
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if ep.interface == req.index as u8 {
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self.bus
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.endpoint_set_enabled(ep.ep_address, iface.current_alt_setting == ep.interface_alt);
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}
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})
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.unwrap();
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// TODO check it is valid (not out of range)
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// TODO actually enable/disable endpoints.
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if let Some(handler) = &mut iface.handler {
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handler.set_alternate_setting(new_altsetting);
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}
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OutResponse::Accepted
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}
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_ => OutResponse::Rejected,
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}
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}
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(RequestType::Standard, Recipient::Endpoint) => match (req.request, req.value) {
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(Request::SET_FEATURE, Request::FEATURE_ENDPOINT_HALT) => {
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let ep_addr = ((req.index as u8) & 0x8f).into();
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self.bus.endpoint_set_stalled(ep_addr, true);
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OutResponse::Accepted
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}
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(Request::CLEAR_FEATURE, Request::FEATURE_ENDPOINT_HALT) => {
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let ep_addr = ((req.index as u8) & 0x8f).into();
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self.bus.endpoint_set_stalled(ep_addr, false);
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OutResponse::Accepted
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}
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_ => OutResponse::Rejected,
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},
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(RequestType::Class, Recipient::Interface) => {
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let iface = match self.interfaces.get_mut(req.index as usize) {
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Some(iface) => iface,
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None => return OutResponse::Rejected,
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};
|
|
match &mut iface.handler {
|
|
Some(handler) => handler.control_out(req, data),
|
|
None => OutResponse::Rejected,
|
|
}
|
|
}
|
|
_ => OutResponse::Rejected,
|
|
}
|
|
}
|
|
|
|
fn handle_control_in<'a>(&'a mut self, req: Request, buf: &'a mut [u8]) -> InResponse<'a> {
|
|
match (req.request_type, req.recipient) {
|
|
(RequestType::Standard, Recipient::Device) => match req.request {
|
|
Request::GET_STATUS => {
|
|
let mut status: u16 = 0x0000;
|
|
if self.self_powered {
|
|
status |= 0x0001;
|
|
}
|
|
if self.remote_wakeup_enabled {
|
|
status |= 0x0002;
|
|
}
|
|
buf[..2].copy_from_slice(&status.to_le_bytes());
|
|
InResponse::Accepted(&buf[..2])
|
|
}
|
|
Request::GET_DESCRIPTOR => self.handle_get_descriptor(req, buf),
|
|
Request::GET_CONFIGURATION => {
|
|
let status = match self.device_state {
|
|
UsbDeviceState::Configured => CONFIGURATION_VALUE,
|
|
_ => CONFIGURATION_NONE,
|
|
};
|
|
buf[0] = status;
|
|
InResponse::Accepted(&buf[..1])
|
|
}
|
|
_ => InResponse::Rejected,
|
|
},
|
|
(RequestType::Standard, Recipient::Interface) => {
|
|
let iface = match self.interfaces.get_mut(req.index as usize) {
|
|
Some(iface) => iface,
|
|
None => return InResponse::Rejected,
|
|
};
|
|
|
|
match req.request {
|
|
Request::GET_STATUS => {
|
|
let status: u16 = 0;
|
|
buf[..2].copy_from_slice(&status.to_le_bytes());
|
|
InResponse::Accepted(&buf[..2])
|
|
}
|
|
Request::GET_INTERFACE => {
|
|
buf[0] = iface.current_alt_setting;
|
|
InResponse::Accepted(&buf[..1])
|
|
}
|
|
Request::GET_DESCRIPTOR => match &mut iface.handler {
|
|
Some(handler) => handler.get_descriptor(req, buf),
|
|
None => InResponse::Rejected,
|
|
},
|
|
_ => InResponse::Rejected,
|
|
}
|
|
}
|
|
(RequestType::Standard, Recipient::Endpoint) => match req.request {
|
|
Request::GET_STATUS => {
|
|
let ep_addr: EndpointAddress = ((req.index as u8) & 0x8f).into();
|
|
let mut status: u16 = 0x0000;
|
|
if self.bus.endpoint_is_stalled(ep_addr) {
|
|
status |= 0x0001;
|
|
}
|
|
buf[..2].copy_from_slice(&status.to_le_bytes());
|
|
InResponse::Accepted(&buf[..2])
|
|
}
|
|
_ => InResponse::Rejected,
|
|
},
|
|
(RequestType::Class, Recipient::Interface) => {
|
|
let iface = match self.interfaces.get_mut(req.index as usize) {
|
|
Some(iface) => iface,
|
|
None => return InResponse::Rejected,
|
|
};
|
|
|
|
match &mut iface.handler {
|
|
Some(handler) => handler.control_in(req, buf),
|
|
None => InResponse::Rejected,
|
|
}
|
|
}
|
|
_ => InResponse::Rejected,
|
|
}
|
|
}
|
|
|
|
fn handle_get_descriptor<'a>(&'a mut self, req: Request, buf: &'a mut [u8]) -> InResponse<'a> {
|
|
let (dtype, index) = req.descriptor_type_index();
|
|
|
|
match dtype {
|
|
descriptor_type::BOS => InResponse::Accepted(self.bos_descriptor),
|
|
descriptor_type::DEVICE => InResponse::Accepted(self.device_descriptor),
|
|
descriptor_type::CONFIGURATION => InResponse::Accepted(self.config_descriptor),
|
|
descriptor_type::STRING => {
|
|
if index == 0 {
|
|
buf[0] = 4; // len
|
|
buf[1] = descriptor_type::STRING;
|
|
buf[2] = lang_id::ENGLISH_US as u8;
|
|
buf[3] = (lang_id::ENGLISH_US >> 8) as u8;
|
|
InResponse::Accepted(&buf[..4])
|
|
} else {
|
|
let s = match index {
|
|
STRING_INDEX_MANUFACTURER => self.config.manufacturer,
|
|
STRING_INDEX_PRODUCT => self.config.product,
|
|
STRING_INDEX_SERIAL_NUMBER => self.config.serial_number,
|
|
_ => {
|
|
// Find out which iface owns this string index.
|
|
let mut index_left = index - STRING_INDEX_CUSTOM_START;
|
|
let mut the_iface = None;
|
|
for iface in &mut self.interfaces {
|
|
if index_left < iface.num_strings {
|
|
the_iface = Some(iface);
|
|
break;
|
|
}
|
|
index_left -= iface.num_strings;
|
|
}
|
|
|
|
if let Some(iface) = the_iface {
|
|
if let Some(handler) = &mut iface.handler {
|
|
let index = StringIndex::new(index);
|
|
let lang_id = req.index;
|
|
handler.get_string(index, lang_id)
|
|
} else {
|
|
warn!("String requested to an interface with no handler.");
|
|
None
|
|
}
|
|
} else {
|
|
warn!("String requested but didn't match to an interface.");
|
|
None
|
|
}
|
|
}
|
|
};
|
|
|
|
if let Some(s) = s {
|
|
if buf.len() < 2 {
|
|
panic!("control buffer too small");
|
|
}
|
|
|
|
buf[1] = descriptor_type::STRING;
|
|
let mut pos = 2;
|
|
for c in s.encode_utf16() {
|
|
if pos + 2 >= buf.len() {
|
|
panic!("control buffer too small");
|
|
}
|
|
|
|
buf[pos..pos + 2].copy_from_slice(&c.to_le_bytes());
|
|
pos += 2;
|
|
}
|
|
|
|
buf[0] = pos as u8;
|
|
InResponse::Accepted(&buf[..pos])
|
|
} else {
|
|
InResponse::Rejected
|
|
}
|
|
}
|
|
}
|
|
_ => InResponse::Rejected,
|
|
}
|
|
}
|
|
}
|
|
|
|
fn first_last<T: Iterator>(iter: T) -> impl Iterator<Item = (bool, bool, T::Item)> {
|
|
let mut iter = iter.peekable();
|
|
let mut first = true;
|
|
core::iter::from_fn(move || {
|
|
let val = iter.next()?;
|
|
let is_first = first;
|
|
first = false;
|
|
let is_last = iter.peek().is_none();
|
|
Some((is_first, is_last, val))
|
|
})
|
|
}
|