From be74dde7d0eafcd1635ccc97d49d78b8e1794f37 Mon Sep 17 00:00:00 2001
From: "Ben V. Brown" <Ralim@Ralimtek.com>
Date: Tue, 19 Dec 2023 11:00:01 +1100
Subject: [PATCH] Extend RTC low power mode for STM32G0

---
 embassy-stm32/src/rtc/mod.rs | 9 +++++++--
 embassy-stm32/src/rtc/v3.rs  | 6 ++++++
 2 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/embassy-stm32/src/rtc/mod.rs b/embassy-stm32/src/rtc/mod.rs
index fa359cda..37496303 100644
--- a/embassy-stm32/src/rtc/mod.rs
+++ b/embassy-stm32/src/rtc/mod.rs
@@ -43,7 +43,7 @@ pub(crate) enum WakeupPrescaler {
     Div16 = 16,
 }
 
-#[cfg(any(stm32wb, stm32f4, stm32l0, stm32g4))]
+#[cfg(any(stm32wb, stm32f4, stm32l0, stm32g4, stm32g0))]
 impl From<WakeupPrescaler> for crate::pac::rtc::vals::Wucksel {
     fn from(val: WakeupPrescaler) -> Self {
         use crate::pac::rtc::vals::Wucksel;
@@ -57,7 +57,7 @@ impl From<WakeupPrescaler> for crate::pac::rtc::vals::Wucksel {
     }
 }
 
-#[cfg(any(stm32wb, stm32f4, stm32l0, stm32g4))]
+#[cfg(any(stm32wb, stm32f4, stm32l0, stm32g4, stm32g0))]
 impl From<crate::pac::rtc::vals::Wucksel> for WakeupPrescaler {
     fn from(val: crate::pac::rtc::vals::Wucksel) -> Self {
         use crate::pac::rtc::vals::Wucksel;
@@ -422,6 +422,11 @@ impl Rtc {
                 #[cfg(any(rtc_v3, rtc_v3u5))]
                 regs.scr().write(|w| w.set_cwutf(Calrf::CLEAR));
 
+                #[cfg(all(stm32g0))]
+                crate::pac::EXTI
+                    .rpr(0)
+                    .modify(|w| w.set_line(RTC::EXTI_WAKEUP_LINE, true));
+                #[cfg(all(not(stm32g0)))]
                 crate::pac::EXTI
                     .pr(0)
                     .modify(|w| w.set_line(RTC::EXTI_WAKEUP_LINE, true));
diff --git a/embassy-stm32/src/rtc/v3.rs b/embassy-stm32/src/rtc/v3.rs
index d2d0d930..6e4fad95 100644
--- a/embassy-stm32/src/rtc/v3.rs
+++ b/embassy-stm32/src/rtc/v3.rs
@@ -132,9 +132,15 @@ impl sealed::Instance for crate::peripherals::RTC {
     #[cfg(all(feature = "low-power", stm32g4))]
     const EXTI_WAKEUP_LINE: usize = 20;
 
+    #[cfg(all(feature = "low-power", stm32g0))]
+    const EXTI_WAKEUP_LINE: usize = 19;
+
     #[cfg(all(feature = "low-power", stm32g4))]
     type WakeupInterrupt = crate::interrupt::typelevel::RTC_WKUP;
 
+    #[cfg(all(feature = "low-power", stm32g0))]
+    type WakeupInterrupt = crate::interrupt::typelevel::RTC_TAMP;
+
     fn read_backup_register(_rtc: &Rtc, register: usize) -> Option<u32> {
         #[allow(clippy::if_same_then_else)]
         if register < Self::BACKUP_REGISTER_COUNT {