low-power: add support for stm32u5

3 files changed, 17 insertions, 5 deletions

diff --git a/embassy-stm32/src/rtc/low_power.rs b/embassy-stm32/src/rtc/low_power.rs
index 875eaa639..bba359f31 100644
--- a/embassy-stm32/src/rtc/low_power.rs
+++ b/embassy-stm32/src/rtc/low_power.rs
@@ -65,7 +65,7 @@ pub(crate) enum WakeupPrescaler {
     Div16 = 16,
 }
 
-#[cfg(any(stm32f4, stm32l0, stm32g4, stm32l4, stm32l5, stm32wb, stm32h5, stm32g0))]
+#[cfg(any(stm32f4, stm32l0, stm32g4, stm32l4, stm32l5, stm32wb, stm32h5, stm32g0, stm32u5))]
 impl From<WakeupPrescaler> for crate::pac::rtc::vals::Wucksel {
     fn from(val: WakeupPrescaler) -> Self {
         use crate::pac::rtc::vals::Wucksel;
@@ -79,7 +79,7 @@ impl From<WakeupPrescaler> for crate::pac::rtc::vals::Wucksel {
     }
 }
 
-#[cfg(any(stm32f4, stm32l0, stm32g4, stm32l4, stm32l5, stm32wb, stm32h5, stm32g0))]
+#[cfg(any(stm32f4, stm32l0, stm32g4, stm32l4, stm32l5, stm32wb, stm32h5, stm32g0, stm32u5))]
 impl From<crate::pac::rtc::vals::Wucksel> for WakeupPrescaler {
     fn from(val: crate::pac::rtc::vals::Wucksel) -> Self {
         use crate::pac::rtc::vals::Wucksel;
@@ -219,12 +219,21 @@ impl Rtc {
 
     pub(crate) fn enable_wakeup_line(&self) {
         use crate::interrupt::typelevel::Interrupt;
-        use crate::pac::EXTI;
 
         <RTC as crate::rtc::SealedInstance>::WakeupInterrupt::unpend();
         unsafe { <RTC as crate::rtc::SealedInstance>::WakeupInterrupt::enable() };
 
-        EXTI.rtsr(0).modify(|w| w.set_line(RTC::EXTI_WAKEUP_LINE, true));
-        EXTI.imr(0).modify(|w| w.set_line(RTC::EXTI_WAKEUP_LINE, true));
+        #[cfg(not(stm32u5))]
+        {
+            use crate::pac::EXTI;
+            EXTI.rtsr(0).modify(|w| w.set_line(RTC::EXTI_WAKEUP_LINE, true));
+            EXTI.imr(0).modify(|w| w.set_line(RTC::EXTI_WAKEUP_LINE, true));
+        }
+        #[cfg(stm32u5)]
+        {
+            use crate::pac::RCC;
+            RCC.srdamr().modify(|w| w.set_rtcapbamen(true));
+            RCC.apb3smenr().modify(|w| w.set_rtcapbsmen(true));
+        }
     }
 }
diff --git a/embassy-stm32/src/rtc/mod.rs b/embassy-stm32/src/rtc/mod.rs
index fe57cfe66..3722d11ab 100644
--- a/embassy-stm32/src/rtc/mod.rs
+++ b/embassy-stm32/src/rtc/mod.rs
@@ -285,6 +285,7 @@ trait SealedInstance {
     const BACKUP_REGISTER_COUNT: usize;
 
     #[cfg(feature = "low-power")]
+    #[cfg(not(stm32u5))]
     const EXTI_WAKEUP_LINE: usize;
 
     #[cfg(feature = "low-power")]
diff --git a/embassy-stm32/src/rtc/v3.rs b/embassy-stm32/src/rtc/v3.rs
index 02fd5272e..12cb10bc7 100644
--- a/embassy-stm32/src/rtc/v3.rs
+++ b/embassy-stm32/src/rtc/v3.rs
@@ -140,6 +140,8 @@ impl SealedInstance for crate::peripherals::RTC {
         } else if #[cfg(any(stm32l5, stm32h5))] {
             const EXTI_WAKEUP_LINE: usize = 17;
             type WakeupInterrupt = crate::interrupt::typelevel::RTC;
+        } else if #[cfg(stm32u5)] {
+            type WakeupInterrupt = crate::interrupt::typelevel::RTC;
         }
     );