diff --git a/drivers/staging/r8188eu/os_dep/ioctl_linux.c b/drivers/staging/r8188eu/os_dep/ioctl_linux.c
index 8c49df724461..9d3488c28048 100644
--- a/drivers/staging/r8188eu/os_dep/ioctl_linux.c
+++ b/drivers/staging/r8188eu/os_dep/ioctl_linux.c
@@ -3621,7 +3621,11 @@ static int rtw_dbg_port(struct net_device *dev,
 		DBG_88E("read RF_reg path(0x%02x), offset(0x%x), value(0x%08x)\n", minor_cmd, arg, rtl8188e_PHY_QueryRFReg(padapter, minor_cmd, arg, 0xffffffff));
 		break;
 	case 0x75:/* write_rf */
-		rtl8188e_PHY_SetRFReg(padapter, minor_cmd, arg, 0xffffffff, extra_arg);
+		if (minor_cmd != RF_PATH_A) {
+			ret = -EINVAL;
+			break;
+		}
+		rtl8188e_PHY_SetRFReg(padapter, RF_PATH_A, arg, 0xffffffff, extra_arg);
 		DBG_88E("write RF_reg path(0x%02x), offset(0x%x), value(0x%08x)\n", minor_cmd, arg, rtl8188e_PHY_QueryRFReg(padapter, minor_cmd, arg, 0xffffffff));
 		break;