5 files changed, 96 insertions, 15 deletions

diff --git a/ci.sh b/ci.sh
index 6a5e6e3f5..ba250fa67 100755
--- a/ci.sh
+++ b/ci.sh
@@ -47,6 +47,7 @@ cargo batch  \
     --- build --release --manifest-path embassy-net/Cargo.toml --target thumbv7em-none-eabi --features defmt,tcp,udp,dns,proto-ipv4,proto-ipv6,medium-ip \
     --- build --release --manifest-path embassy-net/Cargo.toml --target thumbv7em-none-eabi --features defmt,tcp,udp,dns,proto-ipv4,proto-ipv6,medium-ip,medium-ethernet \
     --- build --release --manifest-path embassy-net/Cargo.toml --target thumbv7em-none-eabi --features defmt,tcp,udp,dns,proto-ipv4,proto-ipv6,medium-ip,medium-ethernet,medium-ieee802154 \
+    --- build --release --manifest-path embassy-nrf/Cargo.toml --target thumbv6m-none-eabi --features nrf51,gpiote,time,time-driver-rtc1 \
     --- build --release --manifest-path embassy-nrf/Cargo.toml --target thumbv7em-none-eabi --features nrf52805,gpiote,time,time-driver-rtc1 \
     --- build --release --manifest-path embassy-nrf/Cargo.toml --target thumbv7em-none-eabi --features nrf52810,gpiote,time,time-driver-rtc1 \
     --- build --release --manifest-path embassy-nrf/Cargo.toml --target thumbv7em-none-eabi --features nrf52811,gpiote,time,time-driver-rtc1 \
diff --git a/embassy-nrf/src/gpiote.rs b/embassy-nrf/src/gpiote.rs
index a459446a2..12f4ed0a0 100644
--- a/embassy-nrf/src/gpiote.rs
+++ b/embassy-nrf/src/gpiote.rs
@@ -13,6 +13,10 @@ use crate::interrupt::InterruptExt;
 use crate::ppi::{Event, Task};
 use crate::{interrupt, pac, peripherals};
 
+#[cfg(feature = "nrf51")]
+/// Amount of GPIOTE channels in the chip.
+const CHANNEL_COUNT: usize = 4;
+#[cfg(not(feature = "_nrf51"))]
 /// Amount of GPIOTE channels in the chip.
 const CHANNEL_COUNT: usize = 8;
 
@@ -61,16 +65,20 @@ fn regs() -> &'static pac::gpiote::RegisterBlock {
 }
 
 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) })
+    // no latched GPIO detect in nrf51.
+    #[cfg(not(feature = "_nrf51"))]
+    {
+        #[cfg(any(feature = "nrf52833", feature = "nrf52840"))]
+        let ports = unsafe { &[&*pac::P0::ptr(), &*pac::P1::ptr()] };
+        #[cfg(not(any(feature = "_nrf51", 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
@@ -78,7 +86,7 @@ pub(crate) fn init(irq_prio: crate::interrupt::Priority) {
     let irq = interrupt::GPIOTE0;
     #[cfg(any(feature = "nrf5340-app-ns", feature = "nrf9160-ns"))]
     let irq = interrupt::GPIOTE1;
-    #[cfg(any(feature = "_nrf52", feature = "nrf5340-net"))]
+    #[cfg(any(feature = "_nrf51", feature = "_nrf52", feature = "nrf5340-net"))]
     let irq = interrupt::GPIOTE;
 
     irq.unpend();
@@ -103,7 +111,7 @@ fn GPIOTE1() {
     unsafe { handle_gpiote_interrupt() };
 }
 
-#[cfg(any(feature = "_nrf52", feature = "nrf5340-net"))]
+#[cfg(any(feature = "_nrf51", feature = "_nrf52", feature = "nrf5340-net"))]
 #[cfg(feature = "rt")]
 #[interrupt]
 fn GPIOTE() {
@@ -125,9 +133,29 @@ unsafe fn handle_gpiote_interrupt() {
 
         #[cfg(any(feature = "nrf52833", feature = "nrf52840"))]
         let ports = &[&*pac::P0::ptr(), &*pac::P1::ptr()];
-        #[cfg(not(any(feature = "nrf52833", feature = "nrf52840")))]
+        #[cfg(not(any(feature = "_nrf51", feature = "nrf52833", feature = "nrf52840")))]
         let ports = &[&*pac::P0::ptr()];
+        #[cfg(feature = "_nrf51")]
+        let ports = unsafe { &[&*pac::GPIO::ptr()] };
+
+        #[cfg(feature = "_nrf51")]
+        for (port, &p) in ports.iter().enumerate() {
+            let inp = p.in_.read().bits();
+            for pin in 0..32 {
+                let fired = match p.pin_cnf[pin as usize].read().sense().variant() {
+                    Some(pac::gpio::pin_cnf::SENSE_A::HIGH) => inp & (1 << pin) != 0,
+                    Some(pac::gpio::pin_cnf::SENSE_A::LOW) => inp & (1 << pin) == 0,
+                    _ => false,
+                };
+
+                if fired {
+                    PORT_WAKERS[port * 32 + pin as usize].wake();
+                    p.pin_cnf[pin as usize].modify(|_, w| w.sense().disabled());
+                }
+            }
+        }
 
+        #[cfg(not(feature = "_nrf51"))]
         for (port, &p) in ports.iter().enumerate() {
             let bits = p.latch.read().bits();
             for pin in BitIter(bits) {
@@ -476,9 +504,13 @@ impl_channel!(GPIOTE_CH0, 0);
 impl_channel!(GPIOTE_CH1, 1);
 impl_channel!(GPIOTE_CH2, 2);
 impl_channel!(GPIOTE_CH3, 3);
+#[cfg(not(feature = "nrf51"))]
 impl_channel!(GPIOTE_CH4, 4);
+#[cfg(not(feature = "nrf51"))]
 impl_channel!(GPIOTE_CH5, 5);
+#[cfg(not(feature = "nrf51"))]
 impl_channel!(GPIOTE_CH6, 6);
+#[cfg(not(feature = "nrf51"))]
 impl_channel!(GPIOTE_CH7, 7);
 
 // ====================
diff --git a/examples/nrf51/Cargo.toml b/examples/nrf51/Cargo.toml
index d1e919a33..06c3d20cb 100644
--- a/examples/nrf51/Cargo.toml
+++ b/examples/nrf51/Cargo.toml
@@ -7,7 +7,7 @@ license = "MIT OR Apache-2.0"
 [dependencies]
 embassy-executor = { version = "0.5.0", path = "../../embassy-executor", features = ["task-arena-size-4096", "arch-cortex-m", "executor-thread", "executor-interrupt", "defmt", "integrated-timers"] }
 embassy-time = { version = "0.3.0", path = "../../embassy-time", features = ["defmt", "defmt-timestamp-uptime"] }
-embassy-nrf = { version = "0.1.0", path = "../../embassy-nrf", features = ["defmt", "nrf51", "time-driver-rtc1", "unstable-pac", "time", "rt"] }
+embassy-nrf = { version = "0.1.0", path = "../../embassy-nrf", features = ["defmt", "nrf51", "gpiote", "time-driver-rtc1", "unstable-pac", "time", "rt"] }
 
 defmt = "0.3"
 defmt-rtt = "0.4"
diff --git a/tests/nrf51422/Cargo.toml b/tests/nrf51422/Cargo.toml
index 2cab20ac0..07236987b 100644
--- a/tests/nrf51422/Cargo.toml
+++ b/tests/nrf51422/Cargo.toml
@@ -7,10 +7,11 @@ license = "MIT OR Apache-2.0"
 [dependencies]
 teleprobe-meta = "1"
 
+embassy-futures = { version = "0.1.0", path = "../../embassy-futures" }
 embassy-sync = { version = "0.5.0", path = "../../embassy-sync", features = ["defmt", ] }
 embassy-executor = { version = "0.5.0", path = "../../embassy-executor", features = ["arch-cortex-m", "executor-thread", "defmt", "task-arena-size-128", "integrated-timers"] }
 embassy-time = { version = "0.3.0", path = "../../embassy-time", features = ["defmt",  "defmt-timestamp-uptime"] }
-embassy-nrf = { version = "0.1.0", path = "../../embassy-nrf", features = ["defmt",  "nrf51", "time-driver-rtc1", "unstable-pac", "time"] }
+embassy-nrf = { version = "0.1.0", path = "../../embassy-nrf", features = ["defmt",  "nrf51", "time-driver-rtc1", "unstable-pac", "time", "gpiote"] }
 embedded-io-async = { version = "0.6.1", features = ["defmt-03"] }
 embedded-hal-async = { version = "1.0" }
 
diff --git a/tests/nrf51422/src/bin/gpiote.rs b/tests/nrf51422/src/bin/gpiote.rs
new file mode 100644
index 000000000..330fe993e
--- /dev/null
+++ b/tests/nrf51422/src/bin/gpiote.rs
@@ -0,0 +1,47 @@
+#![no_std]
+#![no_main]
+teleprobe_meta::target!(b"nrf51-dk");
+
+use defmt::{assert, info};
+use embassy_executor::Spawner;
+use embassy_futures::join::join;
+use embassy_nrf::gpio::{Input, Level, Output, OutputDrive, Pull};
+use embassy_time::{Duration, Instant, Timer};
+use {defmt_rtt as _, panic_probe as _};
+
+#[embassy_executor::main]
+async fn main(_spawner: Spawner) {
+    let p = embassy_nrf::init(Default::default());
+
+    let mut input = Input::new(p.P0_13, Pull::Up);
+    let mut output = Output::new(p.P0_14, Level::Low, OutputDrive::Standard);
+
+    let fut1 = async {
+        Timer::after_millis(100).await;
+        output.set_high();
+    };
+    let fut2 = async {
+        let start = Instant::now();
+        input.wait_for_high().await;
+        let dur = Instant::now() - start;
+        assert!((Duration::from_millis(90)..Duration::from_millis(110)).contains(&dur));
+    };
+
+    join(fut1, fut2).await;
+
+    let fut1 = async {
+        Timer::after_millis(100).await;
+        output.set_low();
+    };
+    let fut2 = async {
+        let start = Instant::now();
+        input.wait_for_low().await;
+        let dur = Instant::now() - start;
+        assert!((Duration::from_millis(90)..Duration::from_millis(110)).contains(&dur));
+    };
+
+    join(fut1, fut2).await;
+
+    info!("Test OK");
+    cortex_m::asm::bkpt();
+}