2 files changed, 7 insertions, 1 deletions
diff --git a/testhal/STM32/STM32F4xx/USB_CDC/Makefile b/testhal/STM32/STM32F4xx/USB_CDC/Makefile
index a8a9dd05c..48f6caeb3 100644
--- a/testhal/STM32/STM32F4xx/USB_CDC/Makefile
+++ b/testhal/STM32/STM32F4xx/USB_CDC/Makefile
@@ -5,7 +5,7 @@
 
 # Compiler options here.
 ifeq ($(USE_OPT),)
-  USE_OPT = -O2 -ggdb -fomit-frame-pointer -falign-functions=16
+  USE_OPT = -O0 -ggdb -fomit-frame-pointer -falign-functions=16
 endif
 
 # C specific options here (added to USE_OPT).
diff --git a/testhal/STM32/STM32F4xx/USB_CDC/usbcfg.c b/testhal/STM32/STM32F4xx/USB_CDC/usbcfg.c
index f825ec239..cfe1a7f5c 100644
--- a/testhal/STM32/STM32F4xx/USB_CDC/usbcfg.c
+++ b/testhal/STM32/STM32F4xx/USB_CDC/usbcfg.c
@@ -284,6 +284,12 @@ static void usb_event(USBDriver *usbp, usbevent_t event) {
     chSysUnlockFromISR();
     return;
   case USB_EVENT_SUSPEND:
+    chSysLockFromISR();
+
+    /* Disconnection event on suspend.*/
+    sduDisconnectI(&SDU1);
+
+    chSysUnlockFromISR();
     return;
   case USB_EVENT_WAKEUP:
     return;