stm32: disable HSI if not used

3 files changed, 15 insertions, 0 deletions

diff --git a/embassy-stm32/src/rcc/l.rs b/embassy-stm32/src/rcc/l.rs
index 0d668103c..a1dfefd15 100644
--- a/embassy-stm32/src/rcc/l.rs
+++ b/embassy-stm32/src/rcc/l.rs
@@ -385,6 +385,11 @@ pub(crate) unsafe fn init(config: Config) {
         while !RCC.extcfgr().read().c2hpref() {}
     }
 
+    // Disable HSI if not used
+    if !config.hsi {
+        RCC.cr().modify(|w| w.set_hsion(false));
+    }
+
     config.mux.init();
 
     set_clocks!(
diff --git a/embassy-stm32/src/rcc/u5.rs b/embassy-stm32/src/rcc/u5.rs
index 47cc29c6f..c8c3e4adb 100644
--- a/embassy-stm32/src/rcc/u5.rs
+++ b/embassy-stm32/src/rcc/u5.rs
@@ -467,6 +467,11 @@ pub(crate) unsafe fn init(config: Config) {
     let lse = config.ls.lse.map(|l| l.frequency);
     let lsi = config.ls.lsi.then_some(LSI_FREQ);
 
+    // Disable HSI if not used
+    if !config.hsi {
+        RCC.cr().modify(|w| w.set_hsion(false));
+    }
+
     config.mux.init();
 
     set_clocks!(
diff --git a/embassy-stm32/src/rcc/wba.rs b/embassy-stm32/src/rcc/wba.rs
index 2528996d5..4ab3067bc 100644
--- a/embassy-stm32/src/rcc/wba.rs
+++ b/embassy-stm32/src/rcc/wba.rs
@@ -269,6 +269,11 @@ pub(crate) unsafe fn init(config: Config) {
 
     let lsi = config.ls.lsi.then_some(LSI_FREQ);
 
+    // Disable HSI if not used
+    if !config.hsi {
+        RCC.cr().modify(|w| w.set_hsion(false));
+    }
+
     config.mux.init();
 
     set_clocks!(