embassy/embassy-nrf/src/gpiote.rs
2023-07-05 19:01:28 +02:00

561 lines
16 KiB
Rust

//! GPIO task/event (GPIOTE) driver.
use core::convert::Infallible;
use core::future::{poll_fn, Future};
use core::task::{Context, Poll};
use embassy_hal_common::{impl_peripheral, into_ref, Peripheral, PeripheralRef};
use embassy_sync::waitqueue::AtomicWaker;
use crate::gpio::sealed::Pin as _;
use crate::gpio::{AnyPin, Flex, Input, Output, Pin as GpioPin};
use crate::interrupt::InterruptExt;
use crate::ppi::{Event, Task};
use crate::{interrupt, pac, peripherals};
/// Amount of GPIOTE channels in the chip.
const CHANNEL_COUNT: usize = 8;
#[cfg(any(feature = "nrf52833", feature = "nrf52840"))]
const PIN_COUNT: usize = 48;
#[cfg(not(any(feature = "nrf52833", feature = "nrf52840")))]
const PIN_COUNT: usize = 32;
#[allow(clippy::declare_interior_mutable_const)]
const NEW_AW: AtomicWaker = AtomicWaker::new();
static CHANNEL_WAKERS: [AtomicWaker; CHANNEL_COUNT] = [NEW_AW; CHANNEL_COUNT];
static PORT_WAKERS: [AtomicWaker; PIN_COUNT] = [NEW_AW; PIN_COUNT];
/// Polarity for listening to events for GPIOTE input channels.
pub enum InputChannelPolarity {
/// Don't listen for any pin changes.
None,
/// Listen for high to low changes.
HiToLo,
/// Listen for low to high changes.
LoToHi,
/// Listen for any change, either low to high or high to low.
Toggle,
}
/// Polarity of the OUT task operation for GPIOTE output channels.
pub enum OutputChannelPolarity {
/// Set the pin high.
Set,
/// Set the pin low.
Clear,
/// Toggle the pin.
Toggle,
}
fn regs() -> &'static pac::gpiote::RegisterBlock {
cfg_if::cfg_if! {
if #[cfg(any(feature="nrf5340-app-s", feature="nrf9160-s"))] {
unsafe { &*pac::GPIOTE0::ptr() }
} else if #[cfg(any(feature="nrf5340-app-ns", feature="nrf9160-ns"))] {
unsafe { &*pac::GPIOTE1::ptr() }
} else {
unsafe { &*pac::GPIOTE::ptr() }
}
}
}
pub(crate) fn init(irq_prio: crate::interrupt::Priority) {
#[cfg(any(feature = "nrf52833", feature = "nrf52840"))]
let ports = unsafe { &[&*pac::P0::ptr(), &*pac::P1::ptr()] };
#[cfg(not(any(feature = "nrf52833", feature = "nrf52840")))]
let ports = unsafe { &[&*pac::P0::ptr()] };
for &p in ports {
// Enable latched detection
p.detectmode.write(|w| w.detectmode().ldetect());
// Clear latch
p.latch.write(|w| unsafe { w.bits(0xFFFFFFFF) })
}
// Enable interrupts
#[cfg(any(feature = "nrf5340-app-s", feature = "nrf9160-s"))]
let irq = interrupt::GPIOTE0;
#[cfg(any(feature = "nrf5340-app-ns", feature = "nrf9160-ns"))]
let irq = interrupt::GPIOTE1;
#[cfg(any(feature = "_nrf52", feature = "nrf5340-net"))]
let irq = interrupt::GPIOTE;
irq.unpend();
irq.set_priority(irq_prio);
unsafe { irq.enable() };
let g = regs();
g.events_port.write(|w| w);
g.intenset.write(|w| w.port().set());
}
#[cfg(any(feature = "nrf5340-app-s", feature = "nrf9160-s"))]
#[cfg(feature = "rt")]
#[interrupt]
fn GPIOTE0() {
unsafe { handle_gpiote_interrupt() };
}
#[cfg(any(feature = "nrf5340-app-ns", feature = "nrf9160-ns"))]
#[cfg(feature = "rt")]
#[interrupt]
fn GPIOTE1() {
unsafe { handle_gpiote_interrupt() };
}
#[cfg(any(feature = "_nrf52", feature = "nrf5340-net"))]
#[cfg(feature = "rt")]
#[interrupt]
fn GPIOTE() {
unsafe { handle_gpiote_interrupt() };
}
unsafe fn handle_gpiote_interrupt() {
let g = regs();
for i in 0..CHANNEL_COUNT {
if g.events_in[i].read().bits() != 0 {
g.intenclr.write(|w| w.bits(1 << i));
CHANNEL_WAKERS[i].wake();
}
}
if g.events_port.read().bits() != 0 {
g.events_port.write(|w| w);
#[cfg(any(feature = "nrf52833", feature = "nrf52840"))]
let ports = &[&*pac::P0::ptr(), &*pac::P1::ptr()];
#[cfg(not(any(feature = "nrf52833", feature = "nrf52840")))]
let ports = &[&*pac::P0::ptr()];
for (port, &p) in ports.iter().enumerate() {
let bits = p.latch.read().bits();
for pin in BitIter(bits) {
p.pin_cnf[pin as usize].modify(|_, w| w.sense().disabled());
PORT_WAKERS[port * 32 + pin as usize].wake();
}
p.latch.write(|w| w.bits(bits));
}
}
}
struct BitIter(u32);
impl Iterator for BitIter {
type Item = u32;
fn next(&mut self) -> Option<Self::Item> {
match self.0.trailing_zeros() {
32 => None,
b => {
self.0 &= !(1 << b);
Some(b)
}
}
}
}
/// GPIOTE channel driver in input mode
pub struct InputChannel<'d, C: Channel, T: GpioPin> {
ch: PeripheralRef<'d, C>,
pin: Input<'d, T>,
}
impl<'d, C: Channel, T: GpioPin> Drop for InputChannel<'d, C, T> {
fn drop(&mut self) {
let g = regs();
let num = self.ch.number();
g.config[num].write(|w| w.mode().disabled());
g.intenclr.write(|w| unsafe { w.bits(1 << num) });
}
}
impl<'d, C: Channel, T: GpioPin> InputChannel<'d, C, T> {
/// Create a new GPIOTE input channel driver.
pub fn new(ch: impl Peripheral<P = C> + 'd, pin: Input<'d, T>, polarity: InputChannelPolarity) -> Self {
into_ref!(ch);
let g = regs();
let num = ch.number();
g.config[num].write(|w| {
match polarity {
InputChannelPolarity::HiToLo => w.mode().event().polarity().hi_to_lo(),
InputChannelPolarity::LoToHi => w.mode().event().polarity().lo_to_hi(),
InputChannelPolarity::None => w.mode().event().polarity().none(),
InputChannelPolarity::Toggle => w.mode().event().polarity().toggle(),
};
#[cfg(any(feature = "nrf52833", feature = "nrf52840"))]
w.port().bit(match pin.pin.pin.port() {
crate::gpio::Port::Port0 => false,
crate::gpio::Port::Port1 => true,
});
unsafe { w.psel().bits(pin.pin.pin.pin()) }
});
g.events_in[num].reset();
InputChannel { ch, pin }
}
/// Asynchronously wait for an event in this channel.
pub async fn wait(&self) {
let g = regs();
let num = self.ch.number();
// Enable interrupt
g.events_in[num].reset();
g.intenset.write(|w| unsafe { w.bits(1 << num) });
poll_fn(|cx| {
CHANNEL_WAKERS[num].register(cx.waker());
if g.events_in[num].read().bits() != 0 {
Poll::Ready(())
} else {
Poll::Pending
}
})
.await;
}
/// Returns the IN event, for use with PPI.
pub fn event_in(&self) -> Event<'d> {
let g = regs();
Event::from_reg(&g.events_in[self.ch.number()])
}
}
/// GPIOTE channel driver in output mode
pub struct OutputChannel<'d, C: Channel, T: GpioPin> {
ch: PeripheralRef<'d, C>,
_pin: Output<'d, T>,
}
impl<'d, C: Channel, T: GpioPin> Drop for OutputChannel<'d, C, T> {
fn drop(&mut self) {
let g = regs();
let num = self.ch.number();
g.config[num].write(|w| w.mode().disabled());
g.intenclr.write(|w| unsafe { w.bits(1 << num) });
}
}
impl<'d, C: Channel, T: GpioPin> OutputChannel<'d, C, T> {
/// Create a new GPIOTE output channel driver.
pub fn new(ch: impl Peripheral<P = C> + 'd, pin: Output<'d, T>, polarity: OutputChannelPolarity) -> Self {
into_ref!(ch);
let g = regs();
let num = ch.number();
g.config[num].write(|w| {
w.mode().task();
match pin.is_set_high() {
true => w.outinit().high(),
false => w.outinit().low(),
};
match polarity {
OutputChannelPolarity::Set => w.polarity().lo_to_hi(),
OutputChannelPolarity::Clear => w.polarity().hi_to_lo(),
OutputChannelPolarity::Toggle => w.polarity().toggle(),
};
#[cfg(any(feature = "nrf52833", feature = "nrf52840"))]
w.port().bit(match pin.pin.pin.port() {
crate::gpio::Port::Port0 => false,
crate::gpio::Port::Port1 => true,
});
unsafe { w.psel().bits(pin.pin.pin.pin()) }
});
OutputChannel { ch, _pin: pin }
}
/// Triggers the OUT task (does the action as configured with task_out_polarity, defaults to Toggle).
pub fn out(&self) {
let g = regs();
g.tasks_out[self.ch.number()].write(|w| unsafe { w.bits(1) });
}
/// Triggers the SET task (set associated pin high).
#[cfg(not(feature = "nrf51"))]
pub fn set(&self) {
let g = regs();
g.tasks_set[self.ch.number()].write(|w| unsafe { w.bits(1) });
}
/// Triggers the CLEAR task (set associated pin low).
#[cfg(not(feature = "nrf51"))]
pub fn clear(&self) {
let g = regs();
g.tasks_clr[self.ch.number()].write(|w| unsafe { w.bits(1) });
}
/// Returns the OUT task, for use with PPI.
pub fn task_out(&self) -> Task<'d> {
let g = regs();
Task::from_reg(&g.tasks_out[self.ch.number()])
}
/// Returns the CLR task, for use with PPI.
#[cfg(not(feature = "nrf51"))]
pub fn task_clr(&self) -> Task<'d> {
let g = regs();
Task::from_reg(&g.tasks_clr[self.ch.number()])
}
/// Returns the SET task, for use with PPI.
#[cfg(not(feature = "nrf51"))]
pub fn task_set(&self) -> Task<'d> {
let g = regs();
Task::from_reg(&g.tasks_set[self.ch.number()])
}
}
// =======================
#[must_use = "futures do nothing unless you `.await` or poll them"]
pub(crate) struct PortInputFuture<'a> {
pin: PeripheralRef<'a, AnyPin>,
}
impl<'a> PortInputFuture<'a> {
fn new(pin: impl Peripheral<P = impl GpioPin> + 'a) -> Self {
Self {
pin: pin.into_ref().map_into(),
}
}
}
impl<'a> Unpin for PortInputFuture<'a> {}
impl<'a> Drop for PortInputFuture<'a> {
fn drop(&mut self) {
self.pin.conf().modify(|_, w| w.sense().disabled());
}
}
impl<'a> Future for PortInputFuture<'a> {
type Output = ();
fn poll(self: core::pin::Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
PORT_WAKERS[self.pin.pin_port() as usize].register(cx.waker());
if self.pin.conf().read().sense().is_disabled() {
Poll::Ready(())
} else {
Poll::Pending
}
}
}
impl<'d, T: GpioPin> Input<'d, T> {
/// Wait until the pin is high. If it is already high, return immediately.
pub async fn wait_for_high(&mut self) {
self.pin.wait_for_high().await
}
/// Wait until the pin is low. If it is already low, return immediately.
pub async fn wait_for_low(&mut self) {
self.pin.wait_for_low().await
}
/// Wait for the pin to undergo a transition from low to high.
pub async fn wait_for_rising_edge(&mut self) {
self.pin.wait_for_rising_edge().await
}
/// Wait for the pin to undergo a transition from high to low.
pub async fn wait_for_falling_edge(&mut self) {
self.pin.wait_for_falling_edge().await
}
/// Wait for the pin to undergo any transition, i.e low to high OR high to low.
pub async fn wait_for_any_edge(&mut self) {
self.pin.wait_for_any_edge().await
}
}
impl<'d, T: GpioPin> Flex<'d, T> {
/// Wait until the pin is high. If it is already high, return immediately.
pub async fn wait_for_high(&mut self) {
self.pin.conf().modify(|_, w| w.sense().high());
PortInputFuture::new(&mut self.pin).await
}
/// Wait until the pin is low. If it is already low, return immediately.
pub async fn wait_for_low(&mut self) {
self.pin.conf().modify(|_, w| w.sense().low());
PortInputFuture::new(&mut self.pin).await
}
/// Wait for the pin to undergo a transition from low to high.
pub async fn wait_for_rising_edge(&mut self) {
self.wait_for_low().await;
self.wait_for_high().await;
}
/// Wait for the pin to undergo a transition from high to low.
pub async fn wait_for_falling_edge(&mut self) {
self.wait_for_high().await;
self.wait_for_low().await;
}
/// Wait for the pin to undergo any transition, i.e low to high OR high to low.
pub async fn wait_for_any_edge(&mut self) {
if self.is_high() {
self.pin.conf().modify(|_, w| w.sense().low());
} else {
self.pin.conf().modify(|_, w| w.sense().high());
}
PortInputFuture::new(&mut self.pin).await
}
}
// =======================
mod sealed {
pub trait Channel {}
}
/// GPIOTE channel trait.
///
/// Implemented by all GPIOTE channels.
pub trait Channel: sealed::Channel + Sized {
/// Get the channel number.
fn number(&self) -> usize;
/// Convert this channel to a type-erased `AnyChannel`.
///
/// This allows using several channels in situations that might require
/// them to be the same type, like putting them in an array.
fn degrade(self) -> AnyChannel {
AnyChannel {
number: self.number() as u8,
}
}
}
/// Type-erased channel.
///
/// Obtained by calling `Channel::degrade`.
///
/// This allows using several channels in situations that might require
/// them to be the same type, like putting them in an array.
pub struct AnyChannel {
number: u8,
}
impl_peripheral!(AnyChannel);
impl sealed::Channel for AnyChannel {}
impl Channel for AnyChannel {
fn number(&self) -> usize {
self.number as usize
}
}
macro_rules! impl_channel {
($type:ident, $number:expr) => {
impl sealed::Channel for peripherals::$type {}
impl Channel for peripherals::$type {
fn number(&self) -> usize {
$number as usize
}
}
};
}
impl_channel!(GPIOTE_CH0, 0);
impl_channel!(GPIOTE_CH1, 1);
impl_channel!(GPIOTE_CH2, 2);
impl_channel!(GPIOTE_CH3, 3);
impl_channel!(GPIOTE_CH4, 4);
impl_channel!(GPIOTE_CH5, 5);
impl_channel!(GPIOTE_CH6, 6);
impl_channel!(GPIOTE_CH7, 7);
// ====================
mod eh02 {
use super::*;
impl<'d, C: Channel, T: GpioPin> embedded_hal_02::digital::v2::InputPin for InputChannel<'d, C, T> {
type Error = Infallible;
fn is_high(&self) -> Result<bool, Self::Error> {
Ok(self.pin.is_high())
}
fn is_low(&self) -> Result<bool, Self::Error> {
Ok(self.pin.is_low())
}
}
}
#[cfg(feature = "unstable-traits")]
mod eh1 {
use super::*;
impl<'d, C: Channel, T: GpioPin> embedded_hal_1::digital::ErrorType for InputChannel<'d, C, T> {
type Error = Infallible;
}
impl<'d, C: Channel, T: GpioPin> embedded_hal_1::digital::InputPin for InputChannel<'d, C, T> {
fn is_high(&self) -> Result<bool, Self::Error> {
Ok(self.pin.is_high())
}
fn is_low(&self) -> Result<bool, Self::Error> {
Ok(self.pin.is_low())
}
}
}
#[cfg(all(feature = "unstable-traits", feature = "nightly"))]
mod eha {
use super::*;
impl<'d, T: GpioPin> embedded_hal_async::digital::Wait for Input<'d, T> {
async fn wait_for_high(&mut self) -> Result<(), Self::Error> {
Ok(self.wait_for_high().await)
}
async fn wait_for_low(&mut self) -> Result<(), Self::Error> {
Ok(self.wait_for_low().await)
}
async fn wait_for_rising_edge(&mut self) -> Result<(), Self::Error> {
Ok(self.wait_for_rising_edge().await)
}
async fn wait_for_falling_edge(&mut self) -> Result<(), Self::Error> {
Ok(self.wait_for_falling_edge().await)
}
async fn wait_for_any_edge(&mut self) -> Result<(), Self::Error> {
Ok(self.wait_for_any_edge().await)
}
}
impl<'d, T: GpioPin> embedded_hal_async::digital::Wait for Flex<'d, T> {
async fn wait_for_high(&mut self) -> Result<(), Self::Error> {
Ok(self.wait_for_high().await)
}
async fn wait_for_low(&mut self) -> Result<(), Self::Error> {
Ok(self.wait_for_low().await)
}
async fn wait_for_rising_edge(&mut self) -> Result<(), Self::Error> {
Ok(self.wait_for_rising_edge().await)
}
async fn wait_for_falling_edge(&mut self) -> Result<(), Self::Error> {
Ok(self.wait_for_falling_edge().await)
}
async fn wait_for_any_edge(&mut self) -> Result<(), Self::Error> {
Ok(self.wait_for_any_edge().await)
}
}
}