diff --git a/Kbuild b/Kbuild
index bdfbf96..4ca8f1d 100644
--- a/Kbuild
+++ b/Kbuild
@@ -2279,6 +2279,7 @@
 
 ifeq ($(CONFIG_QCA6290_11AX), y)
 cppflags-y += -DQCA_WIFI_QCA6290_11AX
+cppflags-$(CONFIG_WLAN_TX_FLOW_CONTROL_V2) += -DQCA_AC_BASED_FLOW_CONTROL
 endif
 
 cppflags-$(CONFIG_WLAN_FEATURE_11AX) += -DWLAN_FEATURE_11AX