embassy/embassy-stm32/src/usb/usb.rs
2023-05-19 15:20:37 +02:00

1068 lines
33 KiB
Rust

#![macro_use]
use core::future::poll_fn;
use core::marker::PhantomData;
use core::sync::atomic::{AtomicBool, Ordering};
use core::task::Poll;
use embassy_hal_common::into_ref;
use embassy_sync::waitqueue::AtomicWaker;
use embassy_usb_driver as driver;
use embassy_usb_driver::{
Direction, EndpointAddress, EndpointAllocError, EndpointError, EndpointInfo, EndpointType, Event, Unsupported,
};
use super::{DmPin, DpPin, Instance};
use crate::gpio::sealed::AFType;
use crate::interrupt::InterruptExt;
use crate::pac::usb::regs;
use crate::pac::usb::vals::{EpType, Stat};
use crate::pac::USBRAM;
use crate::rcc::sealed::RccPeripheral;
use crate::Peripheral;
const EP_COUNT: usize = 8;
#[cfg(any(usbram_16x1_512, usbram_16x2_512))]
const USBRAM_SIZE: usize = 512;
#[cfg(usbram_16x2_1024)]
const USBRAM_SIZE: usize = 1024;
#[cfg(usbram_32_2048)]
const USBRAM_SIZE: usize = 2048;
#[cfg(not(usbram_32_2048))]
const USBRAM_ALIGN: usize = 2;
#[cfg(usbram_32_2048)]
const USBRAM_ALIGN: usize = 4;
const NEW_AW: AtomicWaker = AtomicWaker::new();
static BUS_WAKER: AtomicWaker = NEW_AW;
static EP0_SETUP: AtomicBool = AtomicBool::new(false);
static EP_IN_WAKERS: [AtomicWaker; EP_COUNT] = [NEW_AW; EP_COUNT];
static EP_OUT_WAKERS: [AtomicWaker; EP_COUNT] = [NEW_AW; EP_COUNT];
static IRQ_RESET: AtomicBool = AtomicBool::new(false);
static IRQ_SUSPEND: AtomicBool = AtomicBool::new(false);
static IRQ_RESUME: AtomicBool = AtomicBool::new(false);
fn convert_type(t: EndpointType) -> EpType {
match t {
EndpointType::Bulk => EpType::BULK,
EndpointType::Control => EpType::CONTROL,
EndpointType::Interrupt => EpType::INTERRUPT,
EndpointType::Isochronous => EpType::ISO,
}
}
fn invariant(mut r: regs::Epr) -> regs::Epr {
r.set_ctr_rx(true); // don't clear
r.set_ctr_tx(true); // don't clear
r.set_dtog_rx(false); // don't toggle
r.set_dtog_tx(false); // don't toggle
r.set_stat_rx(Stat(0));
r.set_stat_tx(Stat(0));
r
}
fn align_len_up(len: u16) -> u16 {
((len as usize + USBRAM_ALIGN - 1) / USBRAM_ALIGN * USBRAM_ALIGN) as u16
}
// Returns (actual_len, len_bits)
fn calc_out_len(len: u16) -> (u16, u16) {
match len {
// NOTE: this could be 2..=62 with 16bit USBRAM, but not with 32bit. Limit it to 60 for simplicity.
2..=60 => (align_len_up(len), align_len_up(len) / 2 << 10),
61..=1024 => ((len + 31) / 32 * 32, (((len + 31) / 32 - 1) << 10) | 0x8000),
_ => panic!("invalid OUT length {}", len),
}
}
#[cfg(not(usbram_32_2048))]
mod btable {
use super::*;
pub(super) unsafe fn write_in<T: Instance>(index: usize, addr: u16) {
USBRAM.mem(index * 4 + 0).write_value(addr);
}
pub(super) unsafe fn write_in_len<T: Instance>(index: usize, _addr: u16, len: u16) {
USBRAM.mem(index * 4 + 1).write_value(len);
}
pub(super) unsafe fn write_out<T: Instance>(index: usize, addr: u16, max_len_bits: u16) {
USBRAM.mem(index * 4 + 2).write_value(addr);
USBRAM.mem(index * 4 + 3).write_value(max_len_bits);
}
pub(super) unsafe fn read_out_len<T: Instance>(index: usize) -> u16 {
USBRAM.mem(index * 4 + 3).read()
}
}
#[cfg(usbram_32_2048)]
mod btable {
use super::*;
pub(super) unsafe fn write_in<T: Instance>(_index: usize, _addr: u16) {}
pub(super) unsafe fn write_in_len<T: Instance>(index: usize, addr: u16, len: u16) {
USBRAM.mem(index * 2).write_value((addr as u32) | ((len as u32) << 16));
}
pub(super) unsafe fn write_out<T: Instance>(index: usize, addr: u16, max_len_bits: u16) {
USBRAM
.mem(index * 2 + 1)
.write_value((addr as u32) | ((max_len_bits as u32) << 16));
}
pub(super) unsafe fn read_out_len<T: Instance>(index: usize) -> u16 {
(USBRAM.mem(index * 2 + 1).read() >> 16) as u16
}
}
struct EndpointBuffer<T: Instance> {
addr: u16,
len: u16,
_phantom: PhantomData<T>,
}
impl<T: Instance> EndpointBuffer<T> {
fn read(&mut self, buf: &mut [u8]) {
assert!(buf.len() <= self.len as usize);
for i in 0..(buf.len() + USBRAM_ALIGN - 1) / USBRAM_ALIGN {
let val = unsafe { USBRAM.mem(self.addr as usize / USBRAM_ALIGN + i).read() };
let n = USBRAM_ALIGN.min(buf.len() - i * USBRAM_ALIGN);
buf[i * USBRAM_ALIGN..][..n].copy_from_slice(&val.to_le_bytes()[..n]);
}
}
fn write(&mut self, buf: &[u8]) {
assert!(buf.len() <= self.len as usize);
for i in 0..(buf.len() + USBRAM_ALIGN - 1) / USBRAM_ALIGN {
let mut val = [0u8; USBRAM_ALIGN];
let n = USBRAM_ALIGN.min(buf.len() - i * USBRAM_ALIGN);
val[..n].copy_from_slice(&buf[i * USBRAM_ALIGN..][..n]);
#[cfg(not(usbram_32_2048))]
let val = u16::from_le_bytes(val);
#[cfg(usbram_32_2048)]
let val = u32::from_le_bytes(val);
unsafe { USBRAM.mem(self.addr as usize / USBRAM_ALIGN + i).write_value(val) };
}
}
}
#[derive(Debug, Clone, Copy)]
#[cfg_attr(feature = "defmt", derive(defmt::Format))]
struct EndpointData {
ep_type: EndpointType, // only valid if used_in || used_out
used_in: bool,
used_out: bool,
}
pub struct Driver<'d, T: Instance> {
phantom: PhantomData<&'d mut T>,
alloc: [EndpointData; EP_COUNT],
ep_mem_free: u16, // first free address in EP mem, in bytes.
}
impl<'d, T: Instance> Driver<'d, T> {
pub fn new(
_usb: impl Peripheral<P = T> + 'd,
irq: impl Peripheral<P = T::Interrupt> + 'd,
dp: impl Peripheral<P = impl DpPin<T>> + 'd,
dm: impl Peripheral<P = impl DmPin<T>> + 'd,
) -> Self {
into_ref!(irq, dp, dm);
irq.set_handler(Self::on_interrupt);
irq.unpend();
irq.enable();
let regs = T::regs();
#[cfg(stm32l5)]
unsafe {
crate::peripherals::PWR::enable();
crate::pac::PWR.cr2().modify(|w| w.set_usv(true));
}
#[cfg(pwr_h5)]
unsafe {
crate::pac::PWR.usbscr().modify(|w| w.set_usb33sv(true))
}
unsafe {
<T as RccPeripheral>::enable();
<T as RccPeripheral>::reset();
regs.cntr().write(|w| {
w.set_pdwn(false);
w.set_fres(true);
});
#[cfg(time)]
embassy_time::block_for(embassy_time::Duration::from_millis(100));
#[cfg(not(time))]
cortex_m::asm::delay(crate::rcc::get_freqs().sys.0 / 10);
#[cfg(not(usb_v4))]
regs.btable().write(|w| w.set_btable(0));
dp.set_as_af(dp.af_num(), AFType::OutputPushPull);
dm.set_as_af(dm.af_num(), AFType::OutputPushPull);
}
// Initialize the bus so that it signals that power is available
BUS_WAKER.wake();
Self {
phantom: PhantomData,
alloc: [EndpointData {
ep_type: EndpointType::Bulk,
used_in: false,
used_out: false,
}; EP_COUNT],
ep_mem_free: EP_COUNT as u16 * 8, // for each EP, 4 regs, so 8 bytes
}
}
fn on_interrupt(_: *mut ()) {
unsafe {
let regs = T::regs();
//let x = regs.istr().read().0;
//trace!("USB IRQ: {:08x}", x);
let istr = regs.istr().read();
if istr.susp() {
//trace!("USB IRQ: susp");
IRQ_SUSPEND.store(true, Ordering::Relaxed);
regs.cntr().modify(|w| {
w.set_fsusp(true);
w.set_lpmode(true);
});
// Write 0 to clear.
let mut clear = regs::Istr(!0);
clear.set_susp(false);
regs.istr().write_value(clear);
// Wake main thread.
BUS_WAKER.wake();
}
if istr.wkup() {
//trace!("USB IRQ: wkup");
IRQ_RESUME.store(true, Ordering::Relaxed);
regs.cntr().modify(|w| {
w.set_fsusp(false);
w.set_lpmode(false);
});
// Write 0 to clear.
let mut clear = regs::Istr(!0);
clear.set_wkup(false);
regs.istr().write_value(clear);
// Wake main thread.
BUS_WAKER.wake();
}
if istr.reset() {
//trace!("USB IRQ: reset");
IRQ_RESET.store(true, Ordering::Relaxed);
// Write 0 to clear.
let mut clear = regs::Istr(!0);
clear.set_reset(false);
regs.istr().write_value(clear);
// Wake main thread.
BUS_WAKER.wake();
}
if istr.ctr() {
let index = istr.ep_id() as usize;
let mut epr = regs.epr(index).read();
if epr.ctr_rx() {
if index == 0 && epr.setup() {
EP0_SETUP.store(true, Ordering::Relaxed);
}
//trace!("EP {} RX, setup={}", index, epr.setup());
EP_OUT_WAKERS[index].wake();
}
if epr.ctr_tx() {
//trace!("EP {} TX", index);
EP_IN_WAKERS[index].wake();
}
epr.set_dtog_rx(false);
epr.set_dtog_tx(false);
epr.set_stat_rx(Stat(0));
epr.set_stat_tx(Stat(0));
epr.set_ctr_rx(!epr.ctr_rx());
epr.set_ctr_tx(!epr.ctr_tx());
regs.epr(index).write_value(epr);
}
}
}
fn alloc_ep_mem(&mut self, len: u16) -> u16 {
assert!(len as usize % USBRAM_ALIGN == 0);
let addr = self.ep_mem_free;
if addr + len > USBRAM_SIZE as _ {
panic!("Endpoint memory full");
}
self.ep_mem_free += len;
addr
}
fn alloc_endpoint<D: Dir>(
&mut self,
ep_type: EndpointType,
max_packet_size: u16,
interval_ms: u8,
) -> Result<Endpoint<'d, T, D>, driver::EndpointAllocError> {
trace!(
"allocating type={:?} mps={:?} interval_ms={}, dir={:?}",
ep_type,
max_packet_size,
interval_ms,
D::dir()
);
let index = self.alloc.iter_mut().enumerate().find(|(i, ep)| {
if *i == 0 && ep_type != EndpointType::Control {
return false; // reserved for control pipe
}
let used = ep.used_out || ep.used_in;
let used_dir = match D::dir() {
Direction::Out => ep.used_out,
Direction::In => ep.used_in,
};
!used || (ep.ep_type == ep_type && !used_dir)
});
let (index, ep) = match index {
Some(x) => x,
None => return Err(EndpointAllocError),
};
ep.ep_type = ep_type;
let buf = match D::dir() {
Direction::Out => {
assert!(!ep.used_out);
ep.used_out = true;
let (len, len_bits) = calc_out_len(max_packet_size);
let addr = self.alloc_ep_mem(len);
trace!(" len_bits = {:04x}", len_bits);
unsafe { btable::write_out::<T>(index, addr, len_bits) }
EndpointBuffer {
addr,
len,
_phantom: PhantomData,
}
}
Direction::In => {
assert!(!ep.used_in);
ep.used_in = true;
let len = align_len_up(max_packet_size);
let addr = self.alloc_ep_mem(len);
// ep_in_len is written when actually TXing packets.
unsafe { btable::write_in::<T>(index, addr) }
EndpointBuffer {
addr,
len,
_phantom: PhantomData,
}
}
};
trace!(" index={} addr={} len={}", index, buf.addr, buf.len);
Ok(Endpoint {
_phantom: PhantomData,
info: EndpointInfo {
addr: EndpointAddress::from_parts(index, D::dir()),
ep_type,
max_packet_size,
interval_ms,
},
buf,
})
}
}
impl<'d, T: Instance> driver::Driver<'d> for Driver<'d, T> {
type EndpointOut = Endpoint<'d, T, Out>;
type EndpointIn = Endpoint<'d, T, In>;
type ControlPipe = ControlPipe<'d, T>;
type Bus = Bus<'d, T>;
fn alloc_endpoint_in(
&mut self,
ep_type: EndpointType,
max_packet_size: u16,
interval_ms: u8,
) -> Result<Self::EndpointIn, driver::EndpointAllocError> {
self.alloc_endpoint(ep_type, max_packet_size, interval_ms)
}
fn alloc_endpoint_out(
&mut self,
ep_type: EndpointType,
max_packet_size: u16,
interval_ms: u8,
) -> Result<Self::EndpointOut, driver::EndpointAllocError> {
self.alloc_endpoint(ep_type, max_packet_size, interval_ms)
}
fn start(mut self, control_max_packet_size: u16) -> (Self::Bus, Self::ControlPipe) {
let ep_out = self
.alloc_endpoint(EndpointType::Control, control_max_packet_size, 0)
.unwrap();
let ep_in = self
.alloc_endpoint(EndpointType::Control, control_max_packet_size, 0)
.unwrap();
assert_eq!(ep_out.info.addr.index(), 0);
assert_eq!(ep_in.info.addr.index(), 0);
let regs = T::regs();
unsafe {
regs.cntr().write(|w| {
w.set_pdwn(false);
w.set_fres(false);
w.set_resetm(true);
w.set_suspm(true);
w.set_wkupm(true);
w.set_ctrm(true);
});
#[cfg(any(usb_v3, usb_v4))]
regs.bcdr().write(|w| w.set_dppu(true))
}
trace!("enabled");
let mut ep_types = [EpType::BULK; EP_COUNT - 1];
for i in 1..EP_COUNT {
ep_types[i - 1] = convert_type(self.alloc[i].ep_type);
}
(
Bus {
phantom: PhantomData,
ep_types,
inited: false,
},
ControlPipe {
_phantom: PhantomData,
max_packet_size: control_max_packet_size,
ep_out,
ep_in,
},
)
}
}
pub struct Bus<'d, T: Instance> {
phantom: PhantomData<&'d mut T>,
ep_types: [EpType; EP_COUNT - 1],
inited: bool,
}
impl<'d, T: Instance> driver::Bus for Bus<'d, T> {
async fn poll(&mut self) -> Event {
poll_fn(move |cx| unsafe {
BUS_WAKER.register(cx.waker());
if self.inited {
let regs = T::regs();
if IRQ_RESUME.load(Ordering::Acquire) {
IRQ_RESUME.store(false, Ordering::Relaxed);
return Poll::Ready(Event::Resume);
}
if IRQ_RESET.load(Ordering::Acquire) {
IRQ_RESET.store(false, Ordering::Relaxed);
trace!("RESET");
regs.daddr().write(|w| {
w.set_ef(true);
w.set_add(0);
});
regs.epr(0).write(|w| {
w.set_ep_type(EpType::CONTROL);
w.set_stat_rx(Stat::NAK);
w.set_stat_tx(Stat::NAK);
});
for i in 1..EP_COUNT {
regs.epr(i).write(|w| {
w.set_ea(i as _);
w.set_ep_type(self.ep_types[i - 1]);
})
}
for w in &EP_IN_WAKERS {
w.wake()
}
for w in &EP_OUT_WAKERS {
w.wake()
}
return Poll::Ready(Event::Reset);
}
if IRQ_SUSPEND.load(Ordering::Acquire) {
IRQ_SUSPEND.store(false, Ordering::Relaxed);
return Poll::Ready(Event::Suspend);
}
Poll::Pending
} else {
self.inited = true;
return Poll::Ready(Event::PowerDetected);
}
})
.await
}
fn endpoint_set_stalled(&mut self, ep_addr: EndpointAddress, stalled: bool) {
// This can race, so do a retry loop.
let reg = T::regs().epr(ep_addr.index() as _);
match ep_addr.direction() {
Direction::In => {
loop {
let r = unsafe { reg.read() };
match r.stat_tx() {
Stat::DISABLED => break, // if disabled, stall does nothing.
Stat::STALL => break, // done!
_ => {
let want_stat = match stalled {
false => Stat::NAK,
true => Stat::STALL,
};
let mut w = invariant(r);
w.set_stat_tx(Stat(r.stat_tx().0 ^ want_stat.0));
unsafe { reg.write_value(w) };
}
}
}
EP_IN_WAKERS[ep_addr.index()].wake();
}
Direction::Out => {
loop {
let r = unsafe { reg.read() };
match r.stat_rx() {
Stat::DISABLED => break, // if disabled, stall does nothing.
Stat::STALL => break, // done!
_ => {
let want_stat = match stalled {
false => Stat::VALID,
true => Stat::STALL,
};
let mut w = invariant(r);
w.set_stat_rx(Stat(r.stat_rx().0 ^ want_stat.0));
unsafe { reg.write_value(w) };
}
}
}
EP_OUT_WAKERS[ep_addr.index()].wake();
}
}
}
fn endpoint_is_stalled(&mut self, ep_addr: EndpointAddress) -> bool {
let regs = T::regs();
let epr = unsafe { regs.epr(ep_addr.index() as _).read() };
match ep_addr.direction() {
Direction::In => epr.stat_tx() == Stat::STALL,
Direction::Out => epr.stat_rx() == Stat::STALL,
}
}
fn endpoint_set_enabled(&mut self, ep_addr: EndpointAddress, enabled: bool) {
trace!("set_enabled {:x} {}", ep_addr, enabled);
// This can race, so do a retry loop.
let reg = T::regs().epr(ep_addr.index() as _);
trace!("EPR before: {:04x}", unsafe { reg.read() }.0);
match ep_addr.direction() {
Direction::In => {
loop {
let want_stat = match enabled {
false => Stat::DISABLED,
true => Stat::NAK,
};
let r = unsafe { reg.read() };
if r.stat_tx() == want_stat {
break;
}
let mut w = invariant(r);
w.set_stat_tx(Stat(r.stat_tx().0 ^ want_stat.0));
unsafe { reg.write_value(w) };
}
EP_IN_WAKERS[ep_addr.index()].wake();
}
Direction::Out => {
loop {
let want_stat = match enabled {
false => Stat::DISABLED,
true => Stat::VALID,
};
let r = unsafe { reg.read() };
if r.stat_rx() == want_stat {
break;
}
let mut w = invariant(r);
w.set_stat_rx(Stat(r.stat_rx().0 ^ want_stat.0));
unsafe { reg.write_value(w) };
}
EP_OUT_WAKERS[ep_addr.index()].wake();
}
}
trace!("EPR after: {:04x}", unsafe { reg.read() }.0);
}
async fn enable(&mut self) {}
async fn disable(&mut self) {}
async fn remote_wakeup(&mut self) -> Result<(), Unsupported> {
Err(Unsupported)
}
}
trait Dir {
fn dir() -> Direction;
fn waker(i: usize) -> &'static AtomicWaker;
}
pub enum In {}
impl Dir for In {
fn dir() -> Direction {
Direction::In
}
#[inline]
fn waker(i: usize) -> &'static AtomicWaker {
&EP_IN_WAKERS[i]
}
}
pub enum Out {}
impl Dir for Out {
fn dir() -> Direction {
Direction::Out
}
#[inline]
fn waker(i: usize) -> &'static AtomicWaker {
&EP_OUT_WAKERS[i]
}
}
pub struct Endpoint<'d, T: Instance, D> {
_phantom: PhantomData<(&'d mut T, D)>,
info: EndpointInfo,
buf: EndpointBuffer<T>,
}
impl<'d, T: Instance, D> Endpoint<'d, T, D> {
fn write_data(&mut self, buf: &[u8]) {
let index = self.info.addr.index();
self.buf.write(buf);
unsafe { btable::write_in_len::<T>(index, self.buf.addr, buf.len() as _) }
}
fn read_data(&mut self, buf: &mut [u8]) -> Result<usize, EndpointError> {
let index = self.info.addr.index();
let rx_len = unsafe { btable::read_out_len::<T>(index) as usize } & 0x3FF;
trace!("READ DONE, rx_len = {}", rx_len);
if rx_len > buf.len() {
return Err(EndpointError::BufferOverflow);
}
self.buf.read(&mut buf[..rx_len]);
Ok(rx_len)
}
}
impl<'d, T: Instance> driver::Endpoint for Endpoint<'d, T, In> {
fn info(&self) -> &EndpointInfo {
&self.info
}
async fn wait_enabled(&mut self) {
trace!("wait_enabled OUT WAITING");
let index = self.info.addr.index();
poll_fn(|cx| {
EP_OUT_WAKERS[index].register(cx.waker());
let regs = T::regs();
if unsafe { regs.epr(index).read() }.stat_tx() == Stat::DISABLED {
Poll::Pending
} else {
Poll::Ready(())
}
})
.await;
trace!("wait_enabled OUT OK");
}
}
impl<'d, T: Instance> driver::Endpoint for Endpoint<'d, T, Out> {
fn info(&self) -> &EndpointInfo {
&self.info
}
async fn wait_enabled(&mut self) {
trace!("wait_enabled OUT WAITING");
let index = self.info.addr.index();
poll_fn(|cx| {
EP_OUT_WAKERS[index].register(cx.waker());
let regs = T::regs();
if unsafe { regs.epr(index).read() }.stat_rx() == Stat::DISABLED {
Poll::Pending
} else {
Poll::Ready(())
}
})
.await;
trace!("wait_enabled OUT OK");
}
}
impl<'d, T: Instance> driver::EndpointOut for Endpoint<'d, T, Out> {
async fn read(&mut self, buf: &mut [u8]) -> Result<usize, EndpointError> {
trace!("READ WAITING, buf.len() = {}", buf.len());
let index = self.info.addr.index();
let stat = poll_fn(|cx| {
EP_OUT_WAKERS[index].register(cx.waker());
let regs = T::regs();
let stat = unsafe { regs.epr(index).read() }.stat_rx();
if matches!(stat, Stat::NAK | Stat::DISABLED) {
Poll::Ready(stat)
} else {
Poll::Pending
}
})
.await;
if stat == Stat::DISABLED {
return Err(EndpointError::Disabled);
}
let rx_len = self.read_data(buf)?;
let regs = T::regs();
unsafe {
regs.epr(index).write(|w| {
w.set_ep_type(convert_type(self.info.ep_type));
w.set_ea(self.info.addr.index() as _);
w.set_stat_rx(Stat(Stat::NAK.0 ^ Stat::VALID.0));
w.set_stat_tx(Stat(0));
w.set_ctr_rx(true); // don't clear
w.set_ctr_tx(true); // don't clear
})
};
trace!("READ OK, rx_len = {}", rx_len);
Ok(rx_len)
}
}
impl<'d, T: Instance> driver::EndpointIn for Endpoint<'d, T, In> {
async fn write(&mut self, buf: &[u8]) -> Result<(), EndpointError> {
if buf.len() > self.info.max_packet_size as usize {
return Err(EndpointError::BufferOverflow);
}
let index = self.info.addr.index();
trace!("WRITE WAITING");
let stat = poll_fn(|cx| {
EP_IN_WAKERS[index].register(cx.waker());
let regs = T::regs();
let stat = unsafe { regs.epr(index).read() }.stat_tx();
if matches!(stat, Stat::NAK | Stat::DISABLED) {
Poll::Ready(stat)
} else {
Poll::Pending
}
})
.await;
if stat == Stat::DISABLED {
return Err(EndpointError::Disabled);
}
self.write_data(buf);
let regs = T::regs();
unsafe {
regs.epr(index).write(|w| {
w.set_ep_type(convert_type(self.info.ep_type));
w.set_ea(self.info.addr.index() as _);
w.set_stat_tx(Stat(Stat::NAK.0 ^ Stat::VALID.0));
w.set_stat_rx(Stat(0));
w.set_ctr_rx(true); // don't clear
w.set_ctr_tx(true); // don't clear
})
};
trace!("WRITE OK");
Ok(())
}
}
pub struct ControlPipe<'d, T: Instance> {
_phantom: PhantomData<&'d mut T>,
max_packet_size: u16,
ep_in: Endpoint<'d, T, In>,
ep_out: Endpoint<'d, T, Out>,
}
impl<'d, T: Instance> driver::ControlPipe for ControlPipe<'d, T> {
fn max_packet_size(&self) -> usize {
usize::from(self.max_packet_size)
}
async fn setup(&mut self) -> [u8; 8] {
loop {
trace!("SETUP read waiting");
poll_fn(|cx| {
EP_OUT_WAKERS[0].register(cx.waker());
if EP0_SETUP.load(Ordering::Relaxed) {
Poll::Ready(())
} else {
Poll::Pending
}
})
.await;
let mut buf = [0; 8];
let rx_len = self.ep_out.read_data(&mut buf);
if rx_len != Ok(8) {
trace!("SETUP read failed: {:?}", rx_len);
continue;
}
EP0_SETUP.store(false, Ordering::Relaxed);
trace!("SETUP read ok");
return buf;
}
}
async fn data_out(&mut self, buf: &mut [u8], first: bool, last: bool) -> Result<usize, EndpointError> {
let regs = T::regs();
// When a SETUP is received, Stat/Stat is set to NAK.
// On first transfer, we must set Stat=VALID, to get the OUT data stage.
// We want Stat=STALL so that the host gets a STALL if it switches to the status
// stage too soon, except in the last transfer we set Stat=NAK so that it waits
// for the status stage, which we will ACK or STALL later.
if first || last {
let mut stat_rx = 0;
let mut stat_tx = 0;
if first {
// change NAK -> VALID
stat_rx ^= Stat::NAK.0 ^ Stat::VALID.0;
stat_tx ^= Stat::NAK.0 ^ Stat::STALL.0;
}
if last {
// change STALL -> VALID
stat_tx ^= Stat::STALL.0 ^ Stat::NAK.0;
}
// Note: if this is the first AND last transfer, the above effectively
// changes stat_tx like NAK -> NAK, so noop.
unsafe {
regs.epr(0).write(|w| {
w.set_ep_type(EpType::CONTROL);
w.set_stat_rx(Stat(stat_rx));
w.set_stat_tx(Stat(stat_tx));
w.set_ctr_rx(true); // don't clear
w.set_ctr_tx(true); // don't clear
})
}
}
trace!("data_out WAITING, buf.len() = {}", buf.len());
poll_fn(|cx| {
EP_OUT_WAKERS[0].register(cx.waker());
let regs = T::regs();
if unsafe { regs.epr(0).read() }.stat_rx() == Stat::NAK {
Poll::Ready(())
} else {
Poll::Pending
}
})
.await;
if EP0_SETUP.load(Ordering::Relaxed) {
trace!("received another SETUP, aborting data_out.");
return Err(EndpointError::Disabled);
}
let rx_len = self.ep_out.read_data(buf)?;
unsafe {
regs.epr(0).write(|w| {
w.set_ep_type(EpType::CONTROL);
w.set_stat_rx(Stat(match last {
// If last, set STAT_RX=STALL.
true => Stat::NAK.0 ^ Stat::STALL.0,
// Otherwise, set STAT_RX=VALID, to allow the host to send the next packet.
false => Stat::NAK.0 ^ Stat::VALID.0,
}));
w.set_ctr_rx(true); // don't clear
w.set_ctr_tx(true); // don't clear
})
};
Ok(rx_len)
}
async fn data_in(&mut self, data: &[u8], first: bool, last: bool) -> Result<(), EndpointError> {
trace!("control: data_in");
if data.len() > self.ep_in.info.max_packet_size as usize {
return Err(EndpointError::BufferOverflow);
}
let regs = T::regs();
// When a SETUP is received, Stat is set to NAK.
// We want it to be STALL in non-last transfers.
// We want it to be VALID in last transfer, so the HW does the status stage.
if first || last {
let mut stat_rx = 0;
if first {
// change NAK -> STALL
stat_rx ^= Stat::NAK.0 ^ Stat::STALL.0;
}
if last {
// change STALL -> VALID
stat_rx ^= Stat::STALL.0 ^ Stat::VALID.0;
}
// Note: if this is the first AND last transfer, the above effectively
// does a change of NAK -> VALID.
unsafe {
regs.epr(0).write(|w| {
w.set_ep_type(EpType::CONTROL);
w.set_stat_rx(Stat(stat_rx));
w.set_ep_kind(last); // set OUT_STATUS if last.
w.set_ctr_rx(true); // don't clear
w.set_ctr_tx(true); // don't clear
})
}
}
trace!("WRITE WAITING");
poll_fn(|cx| {
EP_IN_WAKERS[0].register(cx.waker());
EP_OUT_WAKERS[0].register(cx.waker());
let regs = T::regs();
if unsafe { regs.epr(0).read() }.stat_tx() == Stat::NAK {
Poll::Ready(())
} else {
Poll::Pending
}
})
.await;
if EP0_SETUP.load(Ordering::Relaxed) {
trace!("received another SETUP, aborting data_in.");
return Err(EndpointError::Disabled);
}
self.ep_in.write_data(data);
let regs = T::regs();
unsafe {
regs.epr(0).write(|w| {
w.set_ep_type(EpType::CONTROL);
w.set_stat_tx(Stat(Stat::NAK.0 ^ Stat::VALID.0));
w.set_ep_kind(last); // set OUT_STATUS if last.
w.set_ctr_rx(true); // don't clear
w.set_ctr_tx(true); // don't clear
})
};
trace!("WRITE OK");
Ok(())
}
async fn accept(&mut self) {
let regs = T::regs();
trace!("control: accept");
self.ep_in.write_data(&[]);
// Set OUT=stall, IN=accept
unsafe {
let epr = regs.epr(0).read();
regs.epr(0).write(|w| {
w.set_ep_type(EpType::CONTROL);
w.set_stat_rx(Stat(epr.stat_rx().0 ^ Stat::STALL.0));
w.set_stat_tx(Stat(epr.stat_tx().0 ^ Stat::VALID.0));
w.set_ctr_rx(true); // don't clear
w.set_ctr_tx(true); // don't clear
});
}
trace!("control: accept WAITING");
// Wait is needed, so that we don't set the address too soon, breaking the status stage.
// (embassy-usb sets the address after accept() returns)
poll_fn(|cx| {
EP_IN_WAKERS[0].register(cx.waker());
let regs = T::regs();
if unsafe { regs.epr(0).read() }.stat_tx() == Stat::NAK {
Poll::Ready(())
} else {
Poll::Pending
}
})
.await;
trace!("control: accept OK");
}
async fn reject(&mut self) {
let regs = T::regs();
trace!("control: reject");
// Set IN+OUT to stall
unsafe {
let epr = regs.epr(0).read();
regs.epr(0).write(|w| {
w.set_ep_type(EpType::CONTROL);
w.set_stat_rx(Stat(epr.stat_rx().0 ^ Stat::STALL.0));
w.set_stat_tx(Stat(epr.stat_tx().0 ^ Stat::STALL.0));
w.set_ctr_rx(true); // don't clear
w.set_ctr_tx(true); // don't clear
});
}
}
async fn accept_set_address(&mut self, addr: u8) {
self.accept().await;
let regs = T::regs();
trace!("setting addr: {}", addr);
unsafe {
regs.daddr().write(|w| {
w.set_ef(true);
w.set_add(addr);
})
}
}
}