diff --git a/include/drv_types.h b/include/drv_types.h
index 15bc66f..cb0fefc 100644
--- a/include/drv_types.h
+++ b/include/drv_types.h
@@ -828,7 +828,7 @@ struct dvobj_priv
 #define rfctl_to_dvobj(rfctl) container_of((rfctl), struct dvobj_priv, rf_ctl)
 
 #ifdef PLATFORM_LINUX
-static struct device *dvobj_to_dev(struct dvobj_priv *dvobj)
+inline static struct device *dvobj_to_dev(struct dvobj_priv *dvobj)
 {
 	/* todo: get interface type from dvobj and the return the dev accordingly */
 #ifdef RTW_DVOBJ_CHIP_HW_TYPE
diff --git a/include/ieee80211.h b/include/ieee80211.h
index 9758e10..56e67b7 100644
--- a/include/ieee80211.h
+++ b/include/ieee80211.h
@@ -1318,18 +1318,18 @@ enum ieee80211_state {
 (((Addr[2]) & 0xff) == 0xff) && (((Addr[3]) & 0xff) == 0xff) && (((Addr[4]) & 0xff) == 0xff) && \
 (((Addr[5]) & 0xff) == 0xff))
 #else
-extern __inline int is_multicast_mac_addr(const u8 *addr)
+inline static int is_multicast_mac_addr(const u8 *addr)
 {
         return ((addr[0] != 0xff) && (0x01 & addr[0]));
 }
 
-extern __inline int is_broadcast_mac_addr(const u8 *addr)
+inline static int is_broadcast_mac_addr(const u8 *addr)
 {
 	return ((addr[0] == 0xff) && (addr[1] == 0xff) && (addr[2] == 0xff) &&   \
 		(addr[3] == 0xff) && (addr[4] == 0xff) && (addr[5] == 0xff));
 }
 
-extern __inline int is_zero_mac_addr(const u8 *addr)
+inline static int is_zero_mac_addr(const u8 *addr)
 {
 	return ((addr[0] == 0x00) && (addr[1] == 0x00) && (addr[2] == 0x00) &&   \
 		(addr[3] == 0x00) && (addr[4] == 0x00) && (addr[5] == 0x00));
diff --git a/include/rtw_android.h b/include/rtw_android.h
index 9609b3a..2e297a9 100644
--- a/include/rtw_android.h
+++ b/include/rtw_android.h
@@ -96,8 +96,8 @@ int wifi_set_power(int on, unsigned long msec);
 int wifi_get_mac_addr(unsigned char *buf);
 void *wifi_get_country_code(char *ccode);
 #else
-static int rtw_android_wifictrl_func_add(void) { return 0; }
-static void rtw_android_wifictrl_func_del(void) {}
+inline static int rtw_android_wifictrl_func_add(void) { return 0; }
+inline static void rtw_android_wifictrl_func_del(void) {}
 #endif /* defined(RTW_ENABLE_WIFI_CONTROL_FUNC) */
 
 #ifdef CONFIG_GPIO_WAKEUP