diff --git a/arch/arm/src/stm32/stm32_dbgmcu.h b/arch/arm/src/stm32/stm32_dbgmcu.h
index d9e1886bb7d..1c6e7f7fd66 100644
--- a/arch/arm/src/stm32/stm32_dbgmcu.h
+++ b/arch/arm/src/stm32/stm32_dbgmcu.h
@@ -58,7 +58,7 @@
  ************************************************************************************/
 
 /************************************************************************************
- * Public Functions
+ * Public Function Prototypes
  ************************************************************************************/
 
 #endif /* __ARCH_ARM_SRC_STM32_STM32_DBGMCU_H */
diff --git a/arch/arm/src/stm32/stm32_lsi.c b/arch/arm/src/stm32/stm32_lsi.c
index a6e7ddc3829..ba219762e89 100644
--- a/arch/arm/src/stm32/stm32_lsi.c
+++ b/arch/arm/src/stm32/stm32_lsi.c
@@ -69,8 +69,8 @@
 
 void stm32_rcc_enablelsi(void)
 {
-  /* Enable the Internal Low-Speed (LSI) RC Oscillator by setting the LSION bit
-   * the RCC CSR register.
+  /* Enable the Internal Low-Speed (LSI) RC Oscillator by setting the LSION
+   * bit in the RCC CSR register.
    */
 
   modifyreg32(STM32_RCC_CSR, 0, RCC_CSR_LSION);
@@ -90,8 +90,8 @@ void stm32_rcc_enablelsi(void)
 
 void stm32_rcc_disablelsi(void)
 {
-  /* Enable the Internal Low-Speed (LSI) RC Oscillator by setting the LSION bit
-   * the RCC CSR register.
+  /* Enable the Internal Low-Speed (LSI) RC Oscillator by setting the LSION
+   * bit in the RCC CSR register.
    */
 
   modifyreg32(STM32_RCC_CSR, RCC_CSR_LSION, 0);
diff --git a/arch/arm/src/stm32/stm32_oneshot.c b/arch/arm/src/stm32/stm32_oneshot.c
index 9e92e09d054..3ee6fe59ff0 100644
--- a/arch/arm/src/stm32/stm32_oneshot.c
+++ b/arch/arm/src/stm32/stm32_oneshot.c
@@ -275,7 +275,8 @@ int stm32_oneshot_start(struct stm32_oneshot_s *oneshot,
   irqstate_t flags;
 
   tmrinfo("handler=%p arg=%p, ts=(%lu, %lu)\n",
-         handler, arg, (unsigned long)ts->tv_sec, (unsigned long)ts->tv_nsec);
+         handler, arg, (unsigned long)ts->tv_sec,
+         (unsigned long)ts->tv_nsec);
   DEBUGASSERT(oneshot && handler && ts);
   DEBUGASSERT(oneshot->tch);
 
diff --git a/arch/arm/src/stm32/stm32_oneshot.h b/arch/arm/src/stm32/stm32_oneshot.h
index d32c924a79b..f0243c34f53 100644
--- a/arch/arm/src/stm32/stm32_oneshot.h
+++ b/arch/arm/src/stm32/stm32_oneshot.h
@@ -80,9 +80,9 @@
 typedef void (*oneshot_handler_t)(void *arg);
 
 /* The oneshot client must allocate an instance of this structure and called
- * stm32_oneshot_initialize() before using the oneshot facilities.  The client
- * should not access the contents of this structure directly since the
- * contents are subject to change.
+ * stm32_oneshot_initialize() before using the oneshot facilities.  The
+ * client should not access the contents of this structure directly since
+ * the contents are subject to change.
  */
 
 struct stm32_oneshot_s
diff --git a/arch/arm/src/stm32/stm32_oneshot_lowerhalf.c b/arch/arm/src/stm32/stm32_oneshot_lowerhalf.c
index 4ea7b2bf857..39954f45a7b 100644
--- a/arch/arm/src/stm32/stm32_oneshot_lowerhalf.c
+++ b/arch/arm/src/stm32/stm32_oneshot_lowerhalf.c
@@ -54,7 +54,8 @@
  * Private Types
  ****************************************************************************/
 
-/* This structure describes the state of the oneshot timer lower-half driver */
+/* This structure describes the state of the oneshot timer lower-half driver
+ */
 
 struct stm32_oneshot_lowerhalf_s
 {