Add basic device state handling for endpoints.

This commit is contained in:
alexmoon 2022-04-02 16:35:03 -04:00 committed by Dario Nieuwenhuis
parent 99f95a33c3
commit 2ce435dc34
5 changed files with 190 additions and 60 deletions

View file

@ -17,6 +17,7 @@ use futures::future::poll_fn;
use futures::Future;
pub use embassy_usb;
use pac::usbd::RegisterBlock;
use crate::interrupt::Interrupt;
use crate::pac;
@ -92,11 +93,11 @@ impl<'d, T: Instance> Driver<'d, T> {
regs.epdatastatus.write(|w| unsafe { w.bits(r) });
READY_ENDPOINTS.fetch_or(r, Ordering::AcqRel);
for i in 1..=7 {
if r & (1 << i) != 0 {
EP_IN_WAKERS[i - 1].wake();
if r & In::mask(i) != 0 {
In::waker(i).wake();
}
if r & (1 << (i + 16)) != 0 {
EP_OUT_WAKERS[i - 1].wake();
if r & Out::mask(i) != 0 {
Out::waker(i).wake();
}
}
}
@ -272,32 +273,48 @@ impl<'d, T: Instance> driver::Bus for Bus<'d, T> {
#[inline]
fn reset(&mut self) {
self.set_configured(false);
}
#[inline]
fn set_configured(&mut self, configured: bool) {
let regs = T::regs();
// TODO: Initialize ISO buffers
// XXX this is not spec compliant; the endpoints should only be enabled after the device
// has been put in the Configured state. However, usb-device provides no hook to do that
unsafe {
regs.epinen.write(|w| w.bits(self.alloc_in.used.into()));
regs.epouten.write(|w| w.bits(self.alloc_out.used.into()));
}
if configured {
// TODO: Initialize ISO buffers
for i in 1..8 {
let out_enabled = self.alloc_out.used & (1 << i) != 0;
regs.epinen.write(|w| w.bits(self.alloc_in.used.into()));
regs.epouten.write(|w| w.bits(self.alloc_out.used.into()));
// when first enabled, bulk/interrupt OUT endpoints will *not* receive data (the
// peripheral will NAK all incoming packets) until we write a zero to the SIZE
// register (see figure 203 of the 52840 manual). To avoid that we write a 0 to the
// SIZE register
if out_enabled {
regs.size.epout[i].reset();
for i in 1..8 {
let out_enabled = self.alloc_out.used & (1 << i) != 0;
// when first enabled, bulk/interrupt OUT endpoints will *not* receive data (the
// peripheral will NAK all incoming packets) until we write a zero to the SIZE
// register (see figure 203 of the 52840 manual). To avoid that we write a 0 to the
// SIZE register
if out_enabled {
regs.size.epout[i].reset();
}
}
// IN endpoints (low bits) default to ready.
// OUT endpoints (high bits) default to NOT ready, they become ready when data comes in.
READY_ENDPOINTS.store(0x0000FFFF, Ordering::Release);
} else {
// Disable all endpoints except EP0
regs.epinen.write(|w| w.bits(0x01));
regs.epouten.write(|w| w.bits(0x01));
READY_ENDPOINTS.store(In::mask(0), Ordering::Release);
}
}
// IN endpoints (low bits) default to ready.
// OUT endpoints (high bits) default to NOT ready, they become ready when data comes in.
READY_ENDPOINTS.store(0x0000FFFF, Ordering::Release);
for i in 1..=7 {
In::waker(i).wake();
Out::waker(i).wake();
}
}
#[inline]
@ -332,6 +349,46 @@ impl<'d, T: Instance> driver::Bus for Bus<'d, T> {
pub enum Out {}
pub enum In {}
trait EndpointDir {
fn waker(i: usize) -> &'static AtomicWaker;
fn mask(i: usize) -> u32;
fn is_enabled(regs: &RegisterBlock, i: usize) -> bool;
}
impl EndpointDir for In {
#[inline]
fn waker(i: usize) -> &'static AtomicWaker {
&EP_IN_WAKERS[i - 1]
}
#[inline]
fn mask(i: usize) -> u32 {
1 << i
}
#[inline]
fn is_enabled(regs: &RegisterBlock, i: usize) -> bool {
(regs.epinen.read().bits() & (1 << i)) != 0
}
}
impl EndpointDir for Out {
#[inline]
fn waker(i: usize) -> &'static AtomicWaker {
&EP_OUT_WAKERS[i - 1]
}
#[inline]
fn mask(i: usize) -> u32 {
1 << (i + 16)
}
#[inline]
fn is_enabled(regs: &RegisterBlock, i: usize) -> bool {
(regs.epouten.read().bits() & (1 << i)) != 0
}
}
pub struct Endpoint<'d, T: Instance, Dir> {
_phantom: PhantomData<(&'d mut T, Dir)>,
info: EndpointInfo,
@ -346,7 +403,7 @@ impl<'d, T: Instance, Dir> Endpoint<'d, T, Dir> {
}
}
impl<'d, T: Instance, Dir> driver::Endpoint for Endpoint<'d, T, Dir> {
impl<'d, T: Instance, Dir: EndpointDir> driver::Endpoint for Endpoint<'d, T, Dir> {
fn info(&self) -> &EndpointInfo {
&self.info
}
@ -358,6 +415,49 @@ impl<'d, T: Instance, Dir> driver::Endpoint for Endpoint<'d, T, Dir> {
fn is_stalled(&self) -> bool {
Driver::<T>::is_stalled(self.info.addr)
}
type WaitEnabledFuture<'a> = impl Future<Output = ()> + 'a where Self: 'a;
fn wait_enabled(&mut self) -> Self::WaitEnabledFuture<'_> {
let i = self.info.addr.index();
assert!(i != 0);
poll_fn(move |cx| {
Dir::waker(i).register(cx.waker());
if Dir::is_enabled(T::regs(), i) {
Poll::Ready(())
} else {
Poll::Pending
}
})
}
}
impl<'d, T: Instance, Dir> Endpoint<'d, T, Dir> {
async fn wait_data_ready(&mut self) -> Result<(), ()>
where
Dir: EndpointDir,
{
let i = self.info.addr.index();
assert!(i != 0);
poll_fn(|cx| {
Dir::waker(i).register(cx.waker());
let r = READY_ENDPOINTS.load(Ordering::Acquire);
if !Dir::is_enabled(T::regs(), i) {
Poll::Ready(Err(()))
} else if r & Dir::mask(i) != 0 {
Poll::Ready(Ok(()))
} else {
Poll::Pending
}
})
.await?;
// Mark as not ready
READY_ENDPOINTS.fetch_and(!Dir::mask(i), Ordering::AcqRel);
Ok(())
}
}
unsafe fn read_dma<T: Instance>(i: usize, buf: &mut [u8]) -> Result<usize, ReadError> {
@ -449,20 +549,9 @@ impl<'d, T: Instance> driver::EndpointOut for Endpoint<'d, T, Out> {
let i = self.info.addr.index();
assert!(i != 0);
// Wait until ready
poll_fn(|cx| {
EP_OUT_WAKERS[i - 1].register(cx.waker());
let r = READY_ENDPOINTS.load(Ordering::Acquire);
if r & (1 << (i + 16)) != 0 {
Poll::Ready(())
} else {
Poll::Pending
}
})
.await;
// Mark as not ready
READY_ENDPOINTS.fetch_and(!(1 << (i + 16)), Ordering::AcqRel);
self.wait_data_ready()
.await
.map_err(|_| ReadError::Disabled)?;
unsafe { read_dma::<T>(i, buf) }
}
@ -477,20 +566,9 @@ impl<'d, T: Instance> driver::EndpointIn for Endpoint<'d, T, In> {
let i = self.info.addr.index();
assert!(i != 0);
// Wait until ready.
poll_fn(|cx| {
EP_IN_WAKERS[i - 1].register(cx.waker());
let r = READY_ENDPOINTS.load(Ordering::Acquire);
if r & (1 << i) != 0 {
Poll::Ready(())
} else {
Poll::Pending
}
})
.await;
// Mark as not ready
READY_ENDPOINTS.fetch_and(!(1 << i), Ordering::AcqRel);
self.wait_data_ready()
.await
.map_err(|_| WriteError::Disabled)?;
unsafe { write_dma::<T>(i, buf) }

View file

@ -273,6 +273,11 @@ impl<'d, D: Driver<'d>> CdcAcmClass<'d, D> {
pub async fn read_packet(&mut self, data: &mut [u8]) -> Result<usize, ReadError> {
self.read_ep.read(data).await
}
/// Waits for the USB host to enable this interface
pub async fn wait_connection(&mut self) {
self.read_ep.wait_enabled().await
}
}
/// Number of stop bits for LineCoding

View file

@ -72,6 +72,9 @@ pub trait Bus {
/// Sets the device USB address to `addr`.
fn set_device_address(&mut self, addr: u8);
/// Sets the device configured state.
fn set_configured(&mut self, configured: bool);
/// Sets or clears the STALL condition for an endpoint. If the endpoint is an OUT endpoint, it
/// should be prepared to receive data again. Only used during control transfers.
fn set_stalled(&mut self, ep_addr: EndpointAddress, stalled: bool);
@ -105,6 +108,10 @@ pub trait Bus {
}
pub trait Endpoint {
type WaitEnabledFuture<'a>: Future<Output = ()> + 'a
where
Self: 'a;
/// Get the endpoint address
fn info(&self) -> &EndpointInfo;
@ -115,6 +122,9 @@ pub trait Endpoint {
/// Gets whether the STALL condition is set for an endpoint.
fn is_stalled(&self) -> bool;
/// Waits for the endpoint to be enabled.
fn wait_enabled(&mut self) -> Self::WaitEnabledFuture<'_>;
// TODO enable/disable?
}
@ -212,6 +222,7 @@ pub enum WriteError {
/// class shouldn't provide more data than the `max_packet_size` it specified when allocating
/// the endpoint.
BufferOverflow,
Disabled,
}
#[derive(Copy, Clone, Eq, PartialEq, Debug)]
@ -223,4 +234,5 @@ pub enum ReadError {
/// should use a buffer that is large enough for the `max_packet_size` it specified when
/// allocating the endpoint.
BufferOverflow,
Disabled,
}

View file

@ -162,18 +162,21 @@ impl<'d, D: Driver<'d>> UsbDevice<'d, D> {
self.remote_wakeup_enabled = true;
self.control.accept(stage)
}
(Request::SET_ADDRESS, 1..=127) => {
self.pending_address = req.value as u8;
(Request::SET_ADDRESS, addr @ 1..=127) => {
self.pending_address = addr as u8;
self.bus.set_device_address(self.pending_address);
self.control.accept(stage)
}
(Request::SET_CONFIGURATION, CONFIGURATION_VALUE_U16) => {
self.device_state = UsbDeviceState::Configured;
self.bus.set_configured(true);
self.control.accept(stage)
}
(Request::SET_CONFIGURATION, CONFIGURATION_NONE_U16) => match self.device_state {
UsbDeviceState::Default => self.control.accept(stage),
_ => {
self.device_state = UsbDeviceState::Addressed;
self.bus.set_configured(false);
self.control.accept(stage)
}
},

View file

@ -4,12 +4,13 @@
#![feature(type_alias_impl_trait)]
use core::mem;
use defmt::*;
use defmt::{info, panic};
use embassy::executor::Spawner;
use embassy_nrf::interrupt;
use embassy_nrf::pac;
use embassy_nrf::usb::Driver;
use embassy_nrf::usb::{Driver, Instance};
use embassy_nrf::Peripherals;
use embassy_usb::driver::{ReadError, WriteError};
use embassy_usb::{Config, UsbDeviceBuilder};
use embassy_usb_serial::{CdcAcmClass, State};
use futures::future::join;
@ -66,12 +67,11 @@ async fn main(_spawner: Spawner, p: Peripherals) {
// Do stuff with the class!
let echo_fut = async {
let mut buf = [0; 64];
loop {
let n = class.read_packet(&mut buf).await.unwrap();
let data = &buf[..n];
info!("data: {:x}", data);
class.write_packet(data).await.unwrap();
class.wait_connection().await;
info!("Connected");
let _ = echo(&mut class).await;
info!("Disconnected");
}
};
@ -79,3 +79,35 @@ async fn main(_spawner: Spawner, p: Peripherals) {
// If we had made everything `'static` above instead, we could do this using separate tasks instead.
join(usb_fut, echo_fut).await;
}
struct Disconnected {}
impl From<ReadError> for Disconnected {
fn from(val: ReadError) -> Self {
match val {
ReadError::BufferOverflow => panic!("Buffer overflow"),
ReadError::Disabled => Disconnected {},
}
}
}
impl From<WriteError> for Disconnected {
fn from(val: WriteError) -> Self {
match val {
WriteError::BufferOverflow => panic!("Buffer overflow"),
WriteError::Disabled => Disconnected {},
}
}
}
async fn echo<'d, T: Instance + 'd>(
class: &mut CdcAcmClass<'d, Driver<'d, T>>,
) -> Result<(), Disconnected> {
let mut buf = [0; 64];
loop {
let n = class.read_packet(&mut buf).await?;
let data = &buf[..n];
info!("data: {:x}", data);
class.write_packet(data).await?;
}
}