4 files changed, 450 insertions, 3 deletions

diff --git a/src/config.rs b/src/config.rs
index 9c0d47ecb..8d52a1d44 100644
--- a/src/config.rs
+++ b/src/config.rs
@@ -9,6 +9,7 @@ pub struct Config {
     pub time_interrupt_priority: Priority,
     pub rtc_interrupt_priority: Priority,
     pub adc_interrupt_priority: Priority,
+    pub gpio_interrupt_priority: Priority,
     pub clock_cfg: ClocksConfig,
 }
 
@@ -19,6 +20,7 @@ impl Default for Config {
             time_interrupt_priority: Priority::from(0),
             rtc_interrupt_priority: Priority::from(0),
             adc_interrupt_priority: Priority::from(0),
+            gpio_interrupt_priority: Priority::from(0),
             clock_cfg: ClocksConfig::default(),
         }
     }
diff --git a/src/gpio.rs b/src/gpio.rs
index 4f79aff93..332c4c8b2 100644
--- a/src/gpio.rs
+++ b/src/gpio.rs
@@ -3,13 +3,96 @@
 //! concrete pin type.
 
 use core::convert::Infallible;
+use core::future::Future;
 use core::marker::PhantomData;
+use core::pin::pin;
 
 use embassy_hal_internal::{Peri, PeripheralType};
+use maitake_sync::WaitMap;
 use paste::paste;
 
+use crate::pac::interrupt;
 use crate::pac::port0::pcr0::{Dse, Inv, Mux, Pe, Ps, Sre};
 
+struct BitIter(u32);
+
+impl Iterator for BitIter {
+    type Item = usize;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        match self.0.trailing_zeros() {
+            32 => None,
+            b => {
+                self.0 &= !(1 << b);
+                Some(b as usize)
+            }
+        }
+    }
+}
+
+const PORT_COUNT: usize = 5;
+
+static PORT_WAIT_MAPS: [WaitMap<usize, ()>; PORT_COUNT] = [
+    WaitMap::new(),
+    WaitMap::new(),
+    WaitMap::new(),
+    WaitMap::new(),
+    WaitMap::new(),
+];
+
+fn irq_handler(port_index: usize, gpio_base: *const crate::pac::gpio0::RegisterBlock) {
+    let gpio = unsafe { &*gpio_base };
+    let isfr = gpio.isfr0().read().bits();
+
+    for pin in BitIter(isfr) {
+        // Clear all pending interrupts
+        gpio.isfr0().write(|w| unsafe { w.bits(1 << pin) });
+        gpio.icr(pin).modify(|_, w| w.irqc().irqc0()); // Disable interrupt
+
+        // Wake the corresponding port waker
+        if let Some(w) = PORT_WAIT_MAPS.get(port_index) {
+            w.wake(&pin, ());
+        }
+    }
+}
+
+#[interrupt]
+fn GPIO0() {
+    irq_handler(0, crate::pac::Gpio0::ptr());
+}
+
+#[interrupt]
+fn GPIO1() {
+    irq_handler(1, crate::pac::Gpio1::ptr());
+}
+
+#[interrupt]
+fn GPIO2() {
+    irq_handler(2, crate::pac::Gpio2::ptr());
+}
+
+#[interrupt]
+fn GPIO3() {
+    irq_handler(3, crate::pac::Gpio3::ptr());
+}
+
+#[interrupt]
+fn GPIO4() {
+    irq_handler(4, crate::pac::Gpio4::ptr());
+}
+
+pub(crate) unsafe fn init() {
+    use embassy_hal_internal::interrupt::InterruptExt;
+
+    crate::pac::interrupt::GPIO0.enable();
+    crate::pac::interrupt::GPIO1.enable();
+    crate::pac::interrupt::GPIO2.enable();
+    crate::pac::interrupt::GPIO3.enable();
+    crate::pac::interrupt::GPIO4.enable();
+
+    cortex_m::interrupt::enable();
+}
+
 /// Logical level for GPIO pins.
 #[derive(Copy, Clone, Eq, PartialEq, Debug)]
 #[cfg_attr(feature = "defmt", derive(defmt::Format))]
@@ -598,6 +681,77 @@ impl<'d> Flex<'d> {
     }
 }
 
+/// Async methods
+impl<'d> Flex<'d> {
+    /// Helper function that waits for a given interrupt trigger
+    async fn wait_for_inner(&mut self, level: crate::pac::gpio0::icr::Irqc) {
+        // First, ensure that we have a waker that is ready for this port+pin
+        let w = PORT_WAIT_MAPS[self.pin.port].wait(self.pin.pin);
+        let mut w = pin!(w);
+        // Wait for the subscription to occur, which requires polling at least once
+        //
+        // This function returns a result, but can only be an Err if:
+        //
+        // * We call `.close()` on a WaitMap, which we never do
+        // * We have a duplicate key, which can't happen because `wait_for_*` methods
+        //   take an &mut ref of their unique port+pin combo
+        //
+        // So we wait for it to complete, but ignore the result.
+        _ = w.as_mut().subscribe().await;
+
+        // Now that our waker is in the map, we can enable the appropriate interrupt
+        //
+        // Clear any existing pending interrupt on this pin
+        self.pin
+            .gpio()
+            .isfr0()
+            .write(|w| unsafe { w.bits(1 << self.pin.pin()) });
+        self.pin.gpio().icr(self.pin.pin()).write(|w| w.isf().isf1());
+
+        // Pin interrupt configuration
+        self.pin
+            .gpio()
+            .icr(self.pin.pin())
+            .modify(|_, w| w.irqc().variant(level));
+
+        // Finally, we can await the matching call to `.wake()` from the interrupt.
+        //
+        // Again, technically, this could return a result, but for the same reasons
+        // as above, this can't be an error in our case, so just wait for it to complete
+        _ = w.await;
+    }
+
+    /// Wait until the pin is high. If it is already high, return immediately.
+    #[inline]
+    pub fn wait_for_high(&mut self) -> impl Future<Output = ()> + use<'_, 'd> {
+        self.wait_for_inner(crate::pac::gpio0::icr::Irqc::Irqc12)
+    }
+
+    /// Wait until the pin is low. If it is already low, return immediately.
+    #[inline]
+    pub fn wait_for_low(&mut self) -> impl Future<Output = ()> + use<'_, 'd> {
+        self.wait_for_inner(crate::pac::gpio0::icr::Irqc::Irqc8)
+    }
+
+    /// Wait for the pin to undergo a transition from low to high.
+    #[inline]
+    pub fn wait_for_rising_edge(&mut self) -> impl Future<Output = ()> + use<'_, 'd> {
+        self.wait_for_inner(crate::pac::gpio0::icr::Irqc::Irqc9)
+    }
+
+    /// Wait for the pin to undergo a transition from high to low.
+    #[inline]
+    pub fn wait_for_falling_edge(&mut self) -> impl Future<Output = ()> + use<'_, 'd> {
+        self.wait_for_inner(crate::pac::gpio0::icr::Irqc::Irqc10)
+    }
+
+    /// Wait for the pin to undergo any transition, i.e low to high OR high to low.
+    #[inline]
+    pub fn wait_for_any_edge(&mut self) -> impl Future<Output = ()> + use<'_, 'd> {
+        self.wait_for_inner(crate::pac::gpio0::icr::Irqc::Irqc11)
+    }
+}
+
 /// GPIO output driver that owns a `Flex` pin.
 pub struct Output<'d> {
     flex: Flex<'d>,
@@ -691,12 +845,99 @@ impl<'d> Input<'d> {
         self.flex
     }
 
-    // Get the pin level.
+    /// Get the pin level.
     pub fn get_level(&self) -> Level {
         self.flex.get_level()
     }
 }
 
+/// Async methods
+impl<'d> Input<'d> {
+    /// Wait until the pin is high. If it is already high, return immediately.
+    #[inline]
+    pub fn wait_for_high(&mut self) -> impl Future<Output = ()> + use<'_, 'd> {
+        self.flex.wait_for_high()
+    }
+
+    /// Wait until the pin is low. If it is already low, return immediately.
+    #[inline]
+    pub fn wait_for_low(&mut self) -> impl Future<Output = ()> + use<'_, 'd> {
+        self.flex.wait_for_low()
+    }
+
+    /// Wait for the pin to undergo a transition from low to high.
+    #[inline]
+    pub fn wait_for_rising_edge(&mut self) -> impl Future<Output = ()> + use<'_, 'd> {
+        self.flex.wait_for_rising_edge()
+    }
+
+    /// Wait for the pin to undergo a transition from high to low.
+    #[inline]
+    pub fn wait_for_falling_edge(&mut self) -> impl Future<Output = ()> + use<'_, 'd> {
+        self.flex.wait_for_falling_edge()
+    }
+
+    /// Wait for the pin to undergo any transition, i.e low to high OR high to low.
+    #[inline]
+    pub fn wait_for_any_edge(&mut self) -> impl Future<Output = ()> + use<'_, 'd> {
+        self.flex.wait_for_any_edge()
+    }
+}
+
+impl embedded_hal_async::digital::Wait for Input<'_> {
+    async fn wait_for_high(&mut self) -> Result<(), Self::Error> {
+        self.wait_for_high().await;
+        Ok(())
+    }
+
+    async fn wait_for_low(&mut self) -> Result<(), Self::Error> {
+        self.wait_for_low().await;
+        Ok(())
+    }
+
+    async fn wait_for_rising_edge(&mut self) -> Result<(), Self::Error> {
+        self.wait_for_rising_edge().await;
+        Ok(())
+    }
+
+    async fn wait_for_falling_edge(&mut self) -> Result<(), Self::Error> {
+        self.wait_for_falling_edge().await;
+        Ok(())
+    }
+
+    async fn wait_for_any_edge(&mut self) -> Result<(), Self::Error> {
+        self.wait_for_any_edge().await;
+        Ok(())
+    }
+}
+
+impl embedded_hal_async::digital::Wait for Flex<'_> {
+    async fn wait_for_high(&mut self) -> Result<(), Self::Error> {
+        self.wait_for_high().await;
+        Ok(())
+    }
+
+    async fn wait_for_low(&mut self) -> Result<(), Self::Error> {
+        self.wait_for_low().await;
+        Ok(())
+    }
+
+    async fn wait_for_rising_edge(&mut self) -> Result<(), Self::Error> {
+        self.wait_for_rising_edge().await;
+        Ok(())
+    }
+
+    async fn wait_for_falling_edge(&mut self) -> Result<(), Self::Error> {
+        self.wait_for_falling_edge().await;
+        Ok(())
+    }
+
+    async fn wait_for_any_edge(&mut self) -> Result<(), Self::Error> {
+        self.wait_for_any_edge().await;
+        Ok(())
+    }
+}
+
 // Both embedded_hal 0.2 and 1.0 must be supported by embassy HALs.
 impl embedded_hal_02::digital::v2::InputPin for Flex<'_> {
     // GPIO operations on this block cannot fail, therefor we set the error type
diff --git a/src/interrupt.rs b/src/interrupt.rs
index f2f1cccac..0490e3a66 100644
--- a/src/interrupt.rs
+++ b/src/interrupt.rs
@@ -8,7 +8,8 @@
 
 mod generated {
     embassy_hal_internal::interrupt_mod!(
-        OS_EVENT, LPUART0, LPI2C0, LPI2C1, LPI2C2, LPI2C3, LPUART1, LPUART2, LPUART3, LPUART4, LPUART5, RTC, ADC1,
+        OS_EVENT, RTC, ADC1, GPIO0, GPIO1, GPIO2, GPIO3, GPIO4, LPI2C0, LPI2C1, LPI2C2, LPI2C3, LPUART0, LPUART1,
+        LPUART2, LPUART3, LPUART4, LPUART5,
     );
 }
 
@@ -292,6 +293,196 @@ impl InterruptExt for Adc {
     }
 }
 
+pub struct Gpio0;
+pub const GPIO0: Gpio0 = Gpio0;
+
+impl InterruptExt for Gpio0 {
+    /// Clear any pending GPIO0 in NVIC.
+    #[inline]
+    fn unpend(&self) {
+        cortex_m::peripheral::NVIC::unpend(Interrupt::GPIO0);
+    }
+
+    /// Set NVIC priority for GPIO0.
+    #[inline]
+    fn set_priority(&self, priority: Priority) {
+        unsafe {
+            let mut nvic = cortex_m::peripheral::Peripherals::steal().NVIC;
+            nvic.set_priority(Interrupt::GPIO0, u8::from(priority));
+        }
+    }
+
+    /// Enable GPIO0 in NVIC.
+    #[inline]
+    unsafe fn enable(&self) {
+        cortex_m::peripheral::NVIC::unmask(Interrupt::GPIO0);
+    }
+
+    /// Disable GPIO0 in NVIC.
+    #[inline]
+    unsafe fn disable(&self) {
+        cortex_m::peripheral::NVIC::mask(Interrupt::GPIO0);
+    }
+
+    /// Check if GPIO0 is pending in NVIC.
+    #[inline]
+    fn is_pending(&self) -> bool {
+        cortex_m::peripheral::NVIC::is_pending(Interrupt::GPIO0)
+    }
+}
+
+pub struct Gpio1;
+pub const GPIO1: Gpio1 = Gpio1;
+
+impl InterruptExt for Gpio1 {
+    /// Clear any pending GPIO1 in NVIC.
+    #[inline]
+    fn unpend(&self) {
+        cortex_m::peripheral::NVIC::unpend(Interrupt::GPIO1);
+    }
+
+    /// Set NVIC priority for GPIO1.
+    #[inline]
+    fn set_priority(&self, priority: Priority) {
+        unsafe {
+            let mut nvic = cortex_m::peripheral::Peripherals::steal().NVIC;
+            nvic.set_priority(Interrupt::GPIO1, u8::from(priority));
+        }
+    }
+
+    /// Enable GPIO1 in NVIC.
+    #[inline]
+    unsafe fn enable(&self) {
+        cortex_m::peripheral::NVIC::unmask(Interrupt::GPIO1);
+    }
+
+    /// Disable GPIO1 in NVIC.
+    #[inline]
+    unsafe fn disable(&self) {
+        cortex_m::peripheral::NVIC::mask(Interrupt::GPIO1);
+    }
+
+    /// Check if GPIO1 is pending in NVIC.
+    #[inline]
+    fn is_pending(&self) -> bool {
+        cortex_m::peripheral::NVIC::is_pending(Interrupt::GPIO1)
+    }
+}
+
+pub struct Gpio2;
+pub const GPIO2: Gpio2 = Gpio2;
+
+impl InterruptExt for Gpio2 {
+    /// Clear any pending GPIO2 in NVIC.
+    #[inline]
+    fn unpend(&self) {
+        cortex_m::peripheral::NVIC::unpend(Interrupt::GPIO2);
+    }
+
+    /// Set NVIC priority for GPIO2.
+    #[inline]
+    fn set_priority(&self, priority: Priority) {
+        unsafe {
+            let mut nvic = cortex_m::peripheral::Peripherals::steal().NVIC;
+            nvic.set_priority(Interrupt::GPIO2, u8::from(priority));
+        }
+    }
+
+    /// Enable GPIO2 in NVIC.
+    #[inline]
+    unsafe fn enable(&self) {
+        cortex_m::peripheral::NVIC::unmask(Interrupt::GPIO2);
+    }
+
+    /// Disable GPIO2 in NVIC.
+    #[inline]
+    unsafe fn disable(&self) {
+        cortex_m::peripheral::NVIC::mask(Interrupt::GPIO2);
+    }
+
+    /// Check if GPIO2 is pending in NVIC.
+    #[inline]
+    fn is_pending(&self) -> bool {
+        cortex_m::peripheral::NVIC::is_pending(Interrupt::GPIO2)
+    }
+}
+
+pub struct Gpio3;
+pub const GPIO3: Gpio3 = Gpio3;
+
+impl InterruptExt for Gpio3 {
+    /// Clear any pending GPIO3 in NVIC.
+    #[inline]
+    fn unpend(&self) {
+        cortex_m::peripheral::NVIC::unpend(Interrupt::GPIO3);
+    }
+
+    /// Set NVIC priority for GPIO3.
+    #[inline]
+    fn set_priority(&self, priority: Priority) {
+        unsafe {
+            let mut nvic = cortex_m::peripheral::Peripherals::steal().NVIC;
+            nvic.set_priority(Interrupt::GPIO3, u8::from(priority));
+        }
+    }
+
+    /// Enable GPIO3 in NVIC.
+    #[inline]
+    unsafe fn enable(&self) {
+        cortex_m::peripheral::NVIC::unmask(Interrupt::GPIO3);
+    }
+
+    /// Disable GPIO3 in NVIC.
+    #[inline]
+    unsafe fn disable(&self) {
+        cortex_m::peripheral::NVIC::mask(Interrupt::GPIO3);
+    }
+
+    /// Check if GPIO3 is pending in NVIC.
+    #[inline]
+    fn is_pending(&self) -> bool {
+        cortex_m::peripheral::NVIC::is_pending(Interrupt::GPIO3)
+    }
+}
+
+pub struct Gpio4;
+pub const GPIO4: Gpio4 = Gpio4;
+
+impl InterruptExt for Gpio4 {
+    /// Clear any pending GPIO4 in NVIC.
+    #[inline]
+    fn unpend(&self) {
+        cortex_m::peripheral::NVIC::unpend(Interrupt::GPIO4);
+    }
+
+    /// Set NVIC priority for GPIO4.
+    #[inline]
+    fn set_priority(&self, priority: Priority) {
+        unsafe {
+            let mut nvic = cortex_m::peripheral::Peripherals::steal().NVIC;
+            nvic.set_priority(Interrupt::GPIO4, u8::from(priority));
+        }
+    }
+
+    /// Enable GPIO4 in NVIC.
+    #[inline]
+    unsafe fn enable(&self) {
+        cortex_m::peripheral::NVIC::unmask(Interrupt::GPIO4);
+    }
+
+    /// Disable GPIO4 in NVIC.
+    #[inline]
+    unsafe fn disable(&self) {
+        cortex_m::peripheral::NVIC::mask(Interrupt::GPIO4);
+    }
+
+    /// Check if GPIO4 is pending in NVIC.
+    #[inline]
+    fn is_pending(&self) -> bool {
+        cortex_m::peripheral::NVIC::is_pending(Interrupt::GPIO4)
+    }
+}
+
 /// Set VTOR (Vector Table Offset) to a RAM-based vector table.
 /// Pass a pointer to the first word in the RAM table (stack pointer slot 0).
 /// Safety: Caller must ensure the RAM table is valid and aligned as required by the core.
diff --git a/src/lib.rs b/src/lib.rs
index 7fccc86c5..fb204d27b 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -18,7 +18,6 @@ pub mod lpuart;
 pub mod ostimer;
 pub mod rtc;
 
-#[cfg(feature = "rt")]
 pub use crate::pac::NVIC_PRIO_BITS;
 
 #[rustfmt::skip]
@@ -347,10 +346,24 @@ pub fn init(cfg: crate::config::Config) -> Peripherals {
     crate::interrupt::RTC.set_priority(cfg.rtc_interrupt_priority);
     // Apply user-configured priority early; enabling is left to examples/apps
     crate::interrupt::ADC1.set_priority(cfg.adc_interrupt_priority);
+    // Apply user-configured priority early; enabling is left to examples/apps
+    crate::interrupt::GPIO0.set_priority(cfg.gpio_interrupt_priority);
+    // Apply user-configured priority early; enabling is left to examples/apps
+    crate::interrupt::GPIO1.set_priority(cfg.gpio_interrupt_priority);
+    // Apply user-configured priority early; enabling is left to examples/apps
+    crate::interrupt::GPIO2.set_priority(cfg.gpio_interrupt_priority);
+    // Apply user-configured priority early; enabling is left to examples/apps
+    crate::interrupt::GPIO3.set_priority(cfg.gpio_interrupt_priority);
+    // Apply user-configured priority early; enabling is left to examples/apps
+    crate::interrupt::GPIO4.set_priority(cfg.gpio_interrupt_priority);
 
     // Configure clocks
     crate::clocks::init(cfg.clock_cfg).unwrap();
 
+    unsafe {
+        crate::gpio::init();
+    }
+
     // Initialize embassy-time global driver backed by OSTIMER0
     #[cfg(feature = "time")]
     crate::ostimer::time_driver::init(crate::config::Config::default().time_interrupt_priority, 1_000_000);