feat(rtic-v2-rtc-monotonics): Addresses some minor issues when checki…

…ng things with the `build-all.py` script.

* Renames the `wait_for_count_change` to `_wait_for_count_change` function name to suppress an unused warning for SAMD11/21 chips.
* Fixes the `metro_m0` example `blinky_rtic.rs` to fix an RTIC v1 item location change.

boards/metro_m0/examples/blinky_rtic.rs

@@ -19,7 +19,7 @@ mod app {
     use hal::clock::{ClockGenId, ClockSource, GenericClockController};
     use hal::pac::Peripherals;
     use hal::prelude::*;
-    use hal::rtc::{Count32Mode, Duration, Rtc};
+    use hal::rtc::{rtic::v1::Duration, Count32Mode, Rtc};
 
     #[local]
     struct Local {}

hal/src/rtc/mod.rs

@@ -14,6 +14,7 @@ use core::marker::PhantomData;
 #[cfg(feature = "sdmmc")]
 use embedded_sdmmc::{TimeSource, Timestamp};
 
+#[cfg(feature = "rtic")]
 mod modes;
 
 #[cfg(feature = "rtic")]

hal/src/rtc/modes.rs

@@ -130,7 +130,7 @@ pub trait RtcMode {
 
             // Errata: The first read of the count is incorrect so we need to read it
             // then wait for it to change.
-            Self::wait_for_count_change(rtc);
+            Self::_wait_for_count_change(rtc);
         }
     }
 
@@ -189,7 +189,7 @@ pub trait RtcMode {
     /// Note that this may not necessarily be the next tick due sync delay.
     /// Beware that this will wait forever if the RTC is disabled!
     #[inline]
-    fn wait_for_count_change(rtc: &Rtc) -> Self::Count {
+    fn _wait_for_count_change(rtc: &Rtc) -> Self::Count {
         let mut last_count = Self::count(rtc);
 
         loop {

hal/src/rtc/rtic/mod.rs

@@ -115,17 +115,21 @@
 //! changes. This is true regardless of the clock rate used, as the
 //! synchronization delay scales along with the clock period.
 
-// TODO: Need to revisit this and either modernize (e.g. it does not use period
-// counting) it or remove it.
-mod v1 {
+/// Items for RTIC v1.
+///
+/// TODO: This probably needs to be modernized (e.g. it does not implement
+/// half-period counting) or deprecated/removed.
+pub mod v1 {
     use crate::rtc::{Count32Mode, Rtc};
     use rtic_monotonic::Monotonic;
 
     /// The RTC clock frequency in Hz.
     pub const CLOCK_FREQ: u32 = 32_768;
 
-    type Instant = fugit::Instant<u32, 1, CLOCK_FREQ>;
-    type Duration = fugit::Duration<u32, 1, CLOCK_FREQ>;
+    /// The [`fugit`] time instant.
+    pub type Instant = fugit::Instant<u32, 1, CLOCK_FREQ>;
+    /// The [`fugit`] time duration.
+    pub type Duration = fugit::Duration<u32, 1, CLOCK_FREQ>;
 
     impl Monotonic for Rtc<Count32Mode> {
         type Instant = Instant;