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rp/uart: extract common code from async and blocking buffered reads

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once we add error propagation the common code will become even larger,
so it makes sense to move it out.
This commit is contained in:
pennae 2023-04-30 07:05:42 +02:00
parent 1c8492bab2
commit 7ab9fe0522
1 changed files with 39 additions and 47 deletions
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86
embassy-rp/src/uart/buffered.rs
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@ -183,64 +183,56 @@ impl<'d, T: Instance> BufferedUartRx<'d, T> {
Self { phantom: PhantomData }
}
fn read<'a>(buf: &'a mut [u8]) -> impl Future<Output = Result<usize, Error>> + 'a {
fn read<'a>(buf: &'a mut [u8]) -> impl Future<Output = Result<usize, Error>> + 'a
where
T: 'd,
{
poll_fn(move |cx| {
if buf.is_empty() {
return Poll::Ready(Ok(0));
if let Poll::Ready(r) = Self::try_read(buf) {
return Poll::Ready(r);
}
let state = T::buffered_state();
let mut rx_reader = unsafe { state.rx_buf.reader() };
let n = rx_reader.pop(|data| {
let n = data.len().min(buf.len());
buf[..n].copy_from_slice(&data[..n]);
n
});
if n == 0 {
state.rx_waker.register(cx.waker());
return Poll::Pending;
}
// (Re-)Enable the interrupt to receive more data in case it was
// disabled because the buffer was full.
let regs = T::regs();
unsafe {
regs.uartimsc().write_set(|w| {
w.set_rxim(true);
w.set_rtim(true);
});
}
Poll::Ready(Ok(n))
T::buffered_state().rx_waker.register(cx.waker());
Poll::Pending
})
}
pub fn blocking_read(&mut self, buf: &mut [u8]) -> Result<usize, Error> {
fn try_read(buf: &mut [u8]) -> Poll<Result<usize, Error>> {
if buf.is_empty() {
return Ok(0);
return Poll::Ready(Ok(0));
}
loop {
let state = T::buffered_state();
let mut rx_reader = unsafe { state.rx_buf.reader() };
let n = rx_reader.pop(|data| {
let n = data.len().min(buf.len());
buf[..n].copy_from_slice(&data[..n]);
n
let state = T::buffered_state();
let mut rx_reader = unsafe { state.rx_buf.reader() };
let n = rx_reader.pop(|data| {
let n = data.len().min(buf.len());
buf[..n].copy_from_slice(&data[..n]);
n
});
let result = if n == 0 {
return Poll::Pending;
} else {
Ok(n)
};
// (Re-)Enable the interrupt to receive more data in case it was
// disabled because the buffer was full.
let regs = T::regs();
unsafe {
regs.uartimsc().write_set(|w| {
w.set_rxim(true);
w.set_rtim(true);
});
}
if n > 0 {
// (Re-)Enable the interrupt to receive more data in case it was
// disabled because the buffer was full.
let regs = T::regs();
unsafe {
regs.uartimsc().write_set(|w| {
w.set_rxim(true);
w.set_rtim(true);
});
}
Poll::Ready(result)
}
return Ok(n);
pub fn blocking_read(&mut self, buf: &mut [u8]) -> Result<usize, Error> {
loop {
match Self::try_read(buf) {
Poll::Ready(res) => return res,
Poll::Pending => continue,
}
}
}