diff --git a/embassy-stm32/src/rcc/bd.rs b/embassy-stm32/src/rcc/bd.rs
index 939c05907..e2c704405 100644
--- a/embassy-stm32/src/rcc/bd.rs
+++ b/embassy-stm32/src/rcc/bd.rs
@@ -92,6 +92,7 @@ pub struct LsConfig {
 }
 
 impl LsConfig {
+    /// Creates an [`LsConfig`] using the LSI when possible.
     pub const fn new() -> Self {
         // on L5, just the fact that LSI is enabled makes things crash.
         // TODO: investigate.