alarm handling to poll hardware status directly; add ci test

embassy-rp/src/rtc/mod.rs

@@ -2,7 +2,7 @@
 mod filter;
 
 use core::future::poll_fn;
-use core::sync::atomic::{compiler_fence, AtomicBool, Ordering};
+use core::sync::atomic::{compiler_fence, Ordering};
 use core::task::Poll;
 
 use embassy_hal_internal::{Peri, PeripheralType};
@@ -21,8 +21,6 @@ use crate::interrupt::{self, InterruptExt};
 
 // Static waker for the interrupt handler
 static WAKER: AtomicWaker = AtomicWaker::new();
-// Static flag to indicate if an alarm has occurred
-static ALARM_OCCURRED: AtomicBool = AtomicBool::new(false);
 
 /// A reference to the real time clock of the system
 pub struct Rtc<'d, T: Instance> {
@@ -259,19 +257,15 @@ impl<'d, T: Instance> Rtc<'d, T> {
         poll_fn(|cx| {
             WAKER.register(cx.waker());
 
-            // If the alarm has occured, we will clear the interrupt and return ready
-            if ALARM_OCCURRED.load(Ordering::SeqCst) {
-                // Clear the alarm occurred flag
-                ALARM_OCCURRED.store(false, Ordering::SeqCst);
-
-                // Clear the interrupt and disable the alarm
+            // Check hardware interrupt status directly
+            if self.inner.regs().ints().read().rtc() {
+                // Clear the interrupt status and disable the alarm
+                self.inner.regs().ints().write(|w| w.set_rtc(true));
                 self.clear_interrupt();
 
-                // Return ready
                 compiler_fence(Ordering::SeqCst);
                 return Poll::Ready(());
             } else {
-                // If the alarm has not occurred, we will return pending
                 return Poll::Pending;
             }
         })
@@ -290,8 +284,7 @@ impl crate::interrupt::typelevel::Handler<crate::interrupt::typelevel::RTC_IRQ>
         let rtc = crate::pac::RTC;
         rtc.irq_setup_0().modify(|w| w.set_match_ena(false));
 
-        // Set the alarm occurred flag and wake the waker
-        ALARM_OCCURRED.store(true, Ordering::SeqCst);
+        // Wake the waker - interrupt status will be checked directly by polling future
         WAKER.wake();
     }
 }

examples/rp/src/bin/rtc_alarm.rs

@@ -47,14 +47,10 @@ async fn main(_spawner: Spawner) {
                 );
 
                 // See if the alarm is already scheduled, if not, schedule it
-                match rtc.alarm_scheduled() {
-                    None => {
-                        info!("Scheduling alarm for 30 seconds from now");
-                        rtc.schedule_alarm(DateTimeFilter::default().second((dt.second + 30) % 60));
-
-                        info!("Alarm scheduled: {}", rtc.alarm_scheduled().unwrap());
-                    }
-                    Some(_) => {}
+                if rtc.alarm_scheduled().is_none() {
+                    info!("Scheduling alarm for 30 seconds from now");
+                    rtc.schedule_alarm(DateTimeFilter::default().second((dt.second + 30) % 60));
+                    info!("Alarm scheduled: {}", rtc.alarm_scheduled().unwrap());
                 }
             }
             // Alarm triggered

tests/rp/Cargo.toml

@@ -64,6 +64,12 @@ name = "float"
 path = "src/bin/float.rs"
 required-features = [ "rp2040",]
 
+# RTC is only available on RP2040
+[[bin]]
+name = "rtc"
+path = "src/bin/rtc.rs"
+required-features = [ "rp2040",]
+
 [profile.dev]
 debug = 2
 debug-assertions = true

tests/rp/src/bin/rtc.rs

@@ -0,0 +1,113 @@
+#![no_std]
+#![no_main]
+#[cfg(feature = "rp2040")]
+teleprobe_meta::target!(b"rpi-pico");
+
+use defmt::{assert, *};
+use embassy_executor::Spawner;
+use embassy_futures::select::{select, Either};
+use embassy_rp::bind_interrupts;
+use embassy_rp::rtc::{DateTime, DateTimeFilter, DayOfWeek, Rtc};
+use embassy_time::{Duration, Instant, Timer};
+use {defmt_rtt as _, panic_probe as _};
+
+// Bind the RTC interrupt to the handler
+bind_interrupts!(struct Irqs {
+    RTC_IRQ => embassy_rp::rtc::InterruptHandler;
+});
+
+#[embassy_executor::main]
+async fn main(_spawner: Spawner) {
+    let p = embassy_rp::init(Default::default());
+    let mut rtc = Rtc::new(p.RTC, Irqs);
+
+    info!("RTC test started");
+
+    // Initialize RTC if not running
+    if !rtc.is_running() {
+        info!("Starting RTC");
+        let now = DateTime {
+            year: 2000,
+            month: 1,
+            day: 1,
+            day_of_week: DayOfWeek::Saturday,
+            hour: 0,
+            minute: 0,
+            second: 0,
+        };
+        rtc.set_datetime(now).unwrap();
+    }
+
+    // Test 1: Basic RTC functionality - read current time
+    let initial_time = rtc.now().unwrap();
+    info!(
+        "Initial time: {}-{:02}-{:02} {}:{:02}:{:02}",
+        initial_time.year,
+        initial_time.month,
+        initial_time.day,
+        initial_time.hour,
+        initial_time.minute,
+        initial_time.second
+    );
+
+    // Test 2: Schedule and wait for alarm
+    info!("Testing alarm scheduling");
+
+    // Schedule alarm for 3 seconds from now
+    let alarm_second = (initial_time.second + 3) % 60;
+    let alarm_filter = DateTimeFilter::default().second(alarm_second);
+
+    info!("Scheduling alarm for second: {}", alarm_second);
+    rtc.schedule_alarm(alarm_filter);
+
+    // Verify alarm is scheduled
+    let scheduled = rtc.alarm_scheduled();
+    assert!(scheduled.is_some(), "Alarm should be scheduled");
+    info!("Alarm scheduled successfully: {}", scheduled.unwrap());
+
+    // Wait for alarm with timeout
+    let alarm_start = Instant::now();
+    match select(Timer::after_secs(5), rtc.wait_for_alarm()).await {
+        Either::First(_) => {
+            core::panic!("Alarm timeout - alarm should have triggered within 5 seconds");
+        }
+        Either::Second(_) => {
+            let alarm_duration = Instant::now() - alarm_start;
+            info!("ALARM TRIGGERED after {:?}", alarm_duration);
+
+            // Verify timing is reasonable (should be around 3 seconds, allow some margin)
+            assert!(
+                alarm_duration >= Duration::from_secs(2) && alarm_duration <= Duration::from_secs(4),
+                "Alarm timing incorrect: {:?}",
+                alarm_duration
+            );
+        }
+    }
+
+    // Test 3: Verify RTC is still running and time has advanced
+    let final_time = rtc.now().unwrap();
+    info!(
+        "Final time: {}-{:02}-{:02} {}:{:02}:{:02}",
+        final_time.year, final_time.month, final_time.day, final_time.hour, final_time.minute, final_time.second
+    );
+
+    // Verify time has advanced (allowing for minute/hour rollover)
+    let time_diff = if final_time.second >= initial_time.second {
+        final_time.second - initial_time.second
+    } else {
+        60 - initial_time.second + final_time.second
+    };
+
+    assert!(time_diff >= 3, "RTC should have advanced by at least 3 seconds");
+    info!("Time advanced by {} seconds", time_diff);
+
+    // Test 4: Verify alarm is no longer scheduled after triggering
+    let post_alarm_scheduled = rtc.alarm_scheduled();
+    assert!(
+        post_alarm_scheduled.is_none(),
+        "Alarm should not be scheduled after triggering"
+    );
+
+    info!("Test OK");
+    cortex_m::asm::bkpt();
+}