diff --git a/readme.txt b/readme.txt
index 7cc5ac572..1693c5f44 100644
--- a/readme.txt
+++ b/readme.txt
@@ -84,7 +84,9 @@
   (backported to 2.2.8).
 - FIX: Fixed broken TIM8 support in STM32 PWM driver (bug 3418620).
 - FIX: Fixed halconf.h file corrupted in some STM32 demos (bug 3418626).
-- NEW: STM32F4 ADC driver implementation.
+- NEW: STM32F4xx ADC driver implementation.
+  TODO: Backport the new solutions implemented in this ADC driver to the
+  STM32L1xx ADC driver.
 - NEW: Added initialization of the NVIC VTOR register to all Cortex-Mx (v7M)
   ports. Also added a port option CORTEX_VTOR_INIT to enforce a different
   default value into the register.