From a49289ce7be3e0d213d26acc1055c37bcb98f4ba Mon Sep 17 00:00:00 2001
From: Christian Enderle <mail@chrenderle.de>
Date: Thu, 21 Nov 2024 19:44:48 +0100
Subject: [PATCH] low-power: add basic support for stm32u0

---
 embassy-stm32/src/low_power.rs     | 11 +++++++++++
 embassy-stm32/src/rtc/low_power.rs |  6 +++---
 embassy-stm32/src/rtc/mod.rs       |  2 +-
 embassy-stm32/src/rtc/v3.rs        |  2 +-
 4 files changed, 16 insertions(+), 5 deletions(-)

diff --git a/embassy-stm32/src/low_power.rs b/embassy-stm32/src/low_power.rs
index d74221864..1423c9538 100644
--- a/embassy-stm32/src/low_power.rs
+++ b/embassy-stm32/src/low_power.rs
@@ -80,6 +80,17 @@ foreach_interrupt! {
     };
 }
 
+// only relevant for stm32u0
+foreach_interrupt! {
+    (RTC, rtc, $block:ident, TAMP, $irq:ident) => {
+        #[interrupt]
+        #[allow(non_snake_case)]
+        unsafe fn $irq() {
+            EXECUTOR.as_mut().unwrap().on_wakeup_irq();
+        }
+    };
+}
+
 #[allow(dead_code)]
 pub(crate) unsafe fn on_wakeup_irq() {
     EXECUTOR.as_mut().unwrap().on_wakeup_irq();
diff --git a/embassy-stm32/src/rtc/low_power.rs b/embassy-stm32/src/rtc/low_power.rs
index bba359f31..5bf8742de 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, stm32u5))]
+#[cfg(any(stm32f4, stm32l0, stm32g4, stm32l4, stm32l5, stm32wb, stm32h5, stm32g0, stm32u5, stm32u0))]
 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, stm32u5))]
+#[cfg(any(stm32f4, stm32l0, stm32g4, stm32l4, stm32l5, stm32wb, stm32h5, stm32g0, stm32u5, stm32u0))]
 impl From<crate::pac::rtc::vals::Wucksel> for WakeupPrescaler {
     fn from(val: crate::pac::rtc::vals::Wucksel) -> Self {
         use crate::pac::rtc::vals::Wucksel;
@@ -223,7 +223,7 @@ impl Rtc {
         <RTC as crate::rtc::SealedInstance>::WakeupInterrupt::unpend();
         unsafe { <RTC as crate::rtc::SealedInstance>::WakeupInterrupt::enable() };
 
-        #[cfg(not(stm32u5))]
+        #[cfg(not(any(stm32u5, stm32u0)))]
         {
             use crate::pac::EXTI;
             EXTI.rtsr(0).modify(|w| w.set_line(RTC::EXTI_WAKEUP_LINE, true));
diff --git a/embassy-stm32/src/rtc/mod.rs b/embassy-stm32/src/rtc/mod.rs
index 3722d11ab..1a668cb37 100644
--- a/embassy-stm32/src/rtc/mod.rs
+++ b/embassy-stm32/src/rtc/mod.rs
@@ -285,7 +285,7 @@ trait SealedInstance {
     const BACKUP_REGISTER_COUNT: usize;
 
     #[cfg(feature = "low-power")]
-    #[cfg(not(stm32u5))]
+    #[cfg(not(any(stm32u5, stm32u0)))]
     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 a15d6ddc8..d543955a4 100644
--- a/embassy-stm32/src/rtc/v3.rs
+++ b/embassy-stm32/src/rtc/v3.rs
@@ -144,7 +144,7 @@ impl SealedInstance for crate::peripherals::RTC {
     cfg_if::cfg_if!(
         if #[cfg(stm32g4)] {
             type WakeupInterrupt = crate::interrupt::typelevel::RTC_WKUP;
-        } else if #[cfg(any(stm32g0))] {
+        } else if #[cfg(any(stm32g0, stm32u0))] {
             type WakeupInterrupt = crate::interrupt::typelevel::RTC_TAMP;
         } else if #[cfg(any(stm32l5, stm32h5, stm32u5))] {
             type WakeupInterrupt = crate::interrupt::typelevel::RTC;