diff --git a/drivers/bl602_driver/startup/GCC/entry.S b/drivers/bl602_driver/startup/GCC/entry.S
index 74c4ec73..eb86024a 100644
--- a/drivers/bl602_driver/startup/GCC/entry.S
+++ b/drivers/bl602_driver/startup/GCC/entry.S
@@ -52,7 +52,6 @@ _enter:
     /* Intial the mtvt, MUST BE 64 bytes aligned*/
     .weak __Vectors
     la t0, __Vectors
-    // From drivers/bl702_driver/risc-v/Core/Include/riscv_encoding.h
     csrw CSR_MTVT, t0
 
 #ifdef __riscv_float_abi_single
@@ -87,21 +86,10 @@ _enter:
     li a2, 0
     call main
 
-    /* If we've made it back here then there's probably something wrong.  We
-     * allow the METAL to register a handler here. */
-    .weak __metal_after_main
-    la ra, __metal_after_main
-    beqz ra, 1f
-    jalr ra
-1:
+    csrci mstatus, (1 << 3)
 
-    /* If that handler returns then there's not a whole lot we can do.  Just
-     * try to make some noise. */
-     la t0, 1f
-     csrw mtvec, t0
-1:
-     lw t1, 0(x0)
-     j 1b
+__exit:
+    j __exit
 
     .cfi_endproc
 
diff --git a/drivers/bl702_driver/hal_drv/inc/hal_i2s.h b/drivers/bl702_driver/hal_drv/inc/hal_i2s.h
index 19488560..434fd8a3 100644
--- a/drivers/bl702_driver/hal_drv/inc/hal_i2s.h
+++ b/drivers/bl702_driver/hal_drv/inc/hal_i2s.h
@@ -109,7 +109,7 @@ typedef struct i2s_device {
     void *rx_dma;
 } i2s_device_t;
 
-#define UART_DEV(dev) ((uart_device_t *)dev)
+#define I2S_DEV(dev) ((i2s_device_t *)dev)
 
 int i2s_register(enum i2s_index_type index, const char *name, uint16_t flag);
 
diff --git a/drivers/bl702_driver/hal_drv/inc/hal_usb.h b/drivers/bl702_driver/hal_drv/inc/hal_usb.h
index 0223b0dd..b964cbdf 100644
--- a/drivers/bl702_driver/hal_drv/inc/hal_usb.h
+++ b/drivers/bl702_driver/hal_drv/inc/hal_usb.h
@@ -27,19 +27,13 @@
 #include "ring_buffer.h"
 #include "bl702_config.h"
 
-#define DEVICE_CTRL_USB_DC_SET_ADDR        0X10
-#define DEVICE_CTRL_USB_DC_SET_ACK         0X11
-#define DEVICE_CTRL_USB_DC_SET_NACK        0X12
-#define DEVICE_CTRL_USB_DC_SET_STALL       0X13
-#define DEVICE_CTRL_USB_DC_CLR_STALL       0X14
-#define DEVICE_CTRL_USB_DC_GET_STALL       0X15
-#define DEVICE_CTRL_USB_DC_CLR_NACK        0X16
-#define DEVICE_CTRL_USB_DC_CHECK_EPCAP     0X17
-#define DEVICE_CTRL_USB_DC_GET_TX_FIFO_CNT 0x18
-#define DEVICE_CTRL_USB_DC_GET_RX_FIFO_CNT 0x19
-#define DEVICE_CTRL_USB_DC_GET_EP_FREE     0x20
-#define DEVICE_CTRL_USB_DC_SET_TX_DMA      0x21
-#define DEVICE_CTRL_USB_DC_SET_RX_DMA      0x22
+#define DEVICE_CTRL_USB_DC_SET_ACK            0X10
+#define DEVICE_CTRL_USB_DC_ENUM_ON            0X11
+#define DEVICE_CTRL_USB_DC_ENUM_OFF           0X12
+#define DEVICE_CTRL_USB_DC_GET_EP_TX_FIFO_CNT 0x13
+#define DEVICE_CTRL_USB_DC_GET_EP_RX_FIFO_CNT 0x14
+#define DEVICE_CTRL_USB_DC_SET_TX_DMA         0x15
+#define DEVICE_CTRL_USB_DC_SET_RX_DMA         0x16
 
 enum usb_index_type {
 #ifdef BSP_USING_USB
@@ -166,8 +160,9 @@ enum usb_error_type {
     USB_DC_EP_DIR_ERR = 1,
     USB_DC_EP_EN_ERR = 2,
     USB_DC_EP_TIMEOUT_ERR = 3,
-    USB_DC_RB_SIZE_SMALL_ERR = 4,
-    USB_DC_ZLP_ERR = 5,
+    USB_DC_ADDR_ERR = 4,
+    USB_DC_RB_SIZE_SMALL_ERR = 5,
+    USB_DC_ZLP_ERR = 6,
 };
 /**
  * @brief USB Endpoint Configuration.
@@ -210,7 +205,11 @@ typedef struct usb_dc_device {
 
 int usb_dc_register(enum usb_index_type index, const char *name, uint16_t flag);
 
+int usb_dc_set_dev_address(const uint8_t addr);
 int usb_dc_ep_open(struct device *dev, const struct usb_dc_ep_cfg *ep_cfg);
+int usb_dc_ep_close(const uint8_t ep);
+int usb_dc_ep_set_stall(const uint8_t ep);
+int usb_dc_ep_clear_stall(const uint8_t ep);
 int usb_dc_ep_is_stalled(struct device *dev, const uint8_t ep, uint8_t *stalled);
 int usb_dc_ep_write(struct device *dev, const uint8_t ep, const uint8_t *data, uint32_t data_len, uint32_t *ret_bytes);
 int usb_dc_ep_read(struct device *dev, const uint8_t ep, uint8_t *data, uint32_t data_len, uint32_t *read_bytes);
diff --git a/drivers/bl702_driver/hal_drv/src/hal_clock.c b/drivers/bl702_driver/hal_drv/src/hal_clock.c
index ea787754..a2378ac5 100644
--- a/drivers/bl702_driver/hal_drv/src/hal_clock.c
+++ b/drivers/bl702_driver/hal_drv/src/hal_clock.c
@@ -147,8 +147,7 @@ void peripheral_clock_init(void)
 #endif
 
 #if defined(BSP_USING_I2S0)
-    GLB_Set_Chip_Out_0_CLK_Sel(GLB_CHIP_CLK_OUT_I2S_REF_CLK);
-    GLB_Set_I2S_CLK(ENABLE, GLB_I2S_OUT_REF_CLK_SRC);
+    GLB_Set_I2S_CLK(ENABLE, GLB_I2S_OUT_REF_CLK_NONE);
 #endif
 #if defined(BSP_USING_ADC0)
 #if BSP_ADC_CLOCK_SOURCE == ROOT_CLOCK_SOURCE_AUPLL
diff --git a/drivers/bl702_driver/hal_drv/src/hal_dma.c b/drivers/bl702_driver/hal_drv/src/hal_dma.c
index dcc2ac90..6d39a1bc 100644
--- a/drivers/bl702_driver/hal_drv/src/hal_dma.c
+++ b/drivers/bl702_driver/hal_drv/src/hal_dma.c
@@ -89,7 +89,8 @@ int dma_open(struct device *dev, uint16_t oflag)
     DMA_Enable();
 
     Interrupt_Handler_Register(DMA_ALL_IRQn, DMA0_IRQ);
-
+    /* Enable uart interrupt*/
+    NVIC_EnableIRQ(DMA_ALL_IRQn);
     return 0;
 }
 /**
@@ -110,8 +111,6 @@ int dma_control(struct device *dev, int cmd, void *args)
             DMA_IntMask(dma_device->ch, DMA_INT_TCOMPLETED, UNMASK);
             DMA_IntMask(dma_device->ch, DMA_INT_ERR, UNMASK);
 
-            /* Enable uart interrupt*/
-            NVIC_EnableIRQ(DMA_ALL_IRQn);
             break;
 
         case DEVICE_CTRL_CLR_INT /* constant-expression */:
@@ -119,8 +118,6 @@ int dma_control(struct device *dev, int cmd, void *args)
             DMA_IntMask(dma_device->ch, DMA_INT_TCOMPLETED, MASK);
             DMA_IntMask(dma_device->ch, DMA_INT_ERR, MASK);
 
-            /* Enable uart interrupt*/
-            NVIC_DisableIRQ(DMA_ALL_IRQn);
             break;
 
         case DEVICE_CTRL_GET_INT /* constant-expression */:
diff --git a/drivers/bl702_driver/hal_drv/src/hal_i2s.c b/drivers/bl702_driver/hal_drv/src/hal_i2s.c
index 9f7a518a..8facad45 100644
--- a/drivers/bl702_driver/hal_drv/src/hal_i2s.c
+++ b/drivers/bl702_driver/hal_drv/src/hal_i2s.c
@@ -39,7 +39,7 @@ int i2s_open(struct device *dev, uint16_t oflag)
     I2S_FifoCfg_Type fifoCfg = { 0 };
 
     GLB_Set_Chip_Out_0_CLK_Sel(GLB_CHIP_CLK_OUT_I2S_REF_CLK);
-    GLB_Set_I2S_CLK(ENABLE, GLB_I2S_OUT_REF_CLK_SRC);
+    GLB_Set_I2S_CLK(ENABLE, GLB_I2S_OUT_REF_CLK_NONE);
 
     /*Finding the right frequency*/
     if (12288000 % (i2s_device->sampl_freq_hz) == 0) {
diff --git a/drivers/bl702_driver/hal_drv/src/hal_uart.c b/drivers/bl702_driver/hal_drv/src/hal_uart.c
index eec66f0a..85936671 100644
--- a/drivers/bl702_driver/hal_drv/src/hal_uart.c
+++ b/drivers/bl702_driver/hal_drv/src/hal_uart.c
@@ -1,24 +1,24 @@
 /**
  * @file hal_uart.c
- * @brief 
- * 
+ * @brief
+ *
  * Copyright (c) 2021 Bouffalolab team
- * 
+ *
  * Licensed to the Apache Software Foundation (ASF) under one or more
  * contributor license agreements.  See the NOTICE file distributed with
  * this work for additional information regarding copyright ownership.  The
  * ASF licenses this file to you under the Apache License, Version 2.0 (the
  * "License"); you may not use this file except in compliance with the
  * License.  You may obtain a copy of the License at
- * 
+ *
  *   http://www.apache.org/licenses/LICENSE-2.0
- * 
+ *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
  * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
  * License for the specific language governing permissions and limitations
  * under the License.
- * 
+ *
  */
 #include "hal_uart.h"
 #include "hal_dma.h"
@@ -44,11 +44,11 @@ static uart_device_t uartx_device[UART_MAX_INDEX] = {
 #endif
 };
 /**
- * @brief 
- * 
- * @param dev 
- * @param oflag 
- * @return int 
+ * @brief
+ *
+ * @param dev
+ * @param oflag
+ * @return int
  */
 int uart_open(struct device *dev, uint16_t oflag)
 {
@@ -114,10 +114,10 @@ int uart_open(struct device *dev, uint16_t oflag)
     return 0;
 }
 /**
- * @brief 
- * 
- * @param dev 
- * @return int 
+ * @brief
+ *
+ * @param dev
+ * @return int
  */
 int uart_close(struct device *dev)
 {
@@ -127,12 +127,12 @@ int uart_close(struct device *dev)
     return 0;
 }
 /**
- * @brief 
- * 
- * @param dev 
- * @param cmd 
- * @param args 
- * @return int 
+ * @brief
+ *
+ * @param dev
+ * @param cmd
+ * @param args
+ * @return int
  */
 int uart_control(struct device *dev, int cmd, void *args)
 {
@@ -254,13 +254,13 @@ int uart_control(struct device *dev, int cmd, void *args)
     return 0;
 }
 /**
- * @brief 
- * 
- * @param dev 
- * @param pos 
- * @param buffer 
- * @param size 
- * @return int 
+ * @brief
+ *
+ * @param dev
+ * @param pos
+ * @param buffer
+ * @param size
+ * @return int
  */
 int uart_write(struct device *dev, uint32_t pos, const void *buffer, uint32_t size)
 {
@@ -278,19 +278,21 @@ int uart_write(struct device *dev, uint32_t pos, const void *buffer, uint32_t si
             dma_channel_start(dma_ch);
         }
         return 0;
-    }
-    return UART_SendData(uart_device->id, (uint8_t *)buffer, size);
+    } else if (dev->oflag & DEVICE_OFLAG_STREAM_TX) {
+        return UART_SendData(uart_device->id, (uint8_t *)buffer, size);
+    } else
+        return -1;
 }
 /**
- * @brief 
- * 
- * @param dev 
- * @param pos 
- * @param buffer 
- * @param size 
- * @return int 
+ * @brief
+ *
+ * @param dev
+ * @param pos
+ * @param buffer
+ * @param size
+ * @return int
  */
-int ATTR_TCM_SECTION uart_read(struct device *dev, uint32_t pos, void *buffer, uint32_t size)
+int uart_read(struct device *dev, uint32_t pos, void *buffer, uint32_t size)
 {
     uart_device_t *uart_device = (uart_device_t *)dev;
     if (dev->oflag & DEVICE_OFLAG_DMA_RX) {
@@ -305,16 +307,23 @@ int ATTR_TCM_SECTION uart_read(struct device *dev, uint32_t pos, void *buffer, u
             dma_reload(dma_ch, (uint32_t)DMA_ADDR_UART1_RDR, (uint32_t)buffer, size);
             dma_channel_start(dma_ch);
         }
+        return 0;
+    } else if (dev->oflag & DEVICE_OFLAG_STREAM_RX) {
+        uint32_t rx_len = 0;
+        while (rx_len < size) {
+            rx_len += UART_ReceiveData(uart_device->id, (uint8_t *)buffer + rx_len, size - rx_len);
+        }
+        return 0;
     }
-    return UART_ReceiveData(uart_device->id, (uint8_t *)buffer, size);
+    return -1;
 }
 /**
- * @brief 
- * 
- * @param index 
- * @param name 
- * @param flag 
- * @return int 
+ * @brief
+ *
+ * @param index
+ * @param name
+ * @param flag
+ * @return int
  */
 int uart_register(enum uart_index_type index, const char *name, uint16_t flag)
 {
@@ -338,11 +347,11 @@ int uart_register(enum uart_index_type index, const char *name, uint16_t flag)
     return device_register(dev, name, flag);
 }
 /**
- * @brief 
- * 
- * @param handle 
+ * @brief
+ *
+ * @param handle
  */
-void ATTR_TCM_SECTION uart_isr(uart_device_t *handle)
+void uart_isr(uart_device_t *handle)
 {
     uint32_t tmpVal = 0;
     uint32_t maskVal = 0;
@@ -410,8 +419,8 @@ void ATTR_TCM_SECTION uart_isr(uart_device_t *handle)
 
 #ifdef BSP_USING_UART0
 /**
- * @brief 
- * 
+ * @brief
+ *
  */
 void UART0_IRQ(void)
 {
@@ -420,8 +429,8 @@ void UART0_IRQ(void)
 #endif
 #ifdef BSP_USING_UART1
 /**
- * @brief 
- * 
+ * @brief
+ *
  */
 void UART1_IRQ(void)
 {
diff --git a/drivers/bl702_driver/hal_drv/src/hal_usb.c b/drivers/bl702_driver/hal_drv/src/hal_usb.c
index 59c06028..4422746e 100644
--- a/drivers/bl702_driver/hal_drv/src/hal_usb.c
+++ b/drivers/bl702_driver/hal_drv/src/hal_usb.c
@@ -333,72 +333,33 @@ int usb_control(struct device *dev, int cmd, void *args)
 
                 offset++;
             }
-        } break;
-
+            break;
+        }
         case DEVICE_CTRL_CLR_INT /* constant-expression */:
-            /* code */
-
             break;
 
-        case DEVICE_CTRL_GET_INT /* constant-expression */:
-            /* code */
-            break;
-
-        case DEVICE_CTRL_CONFIG /* constant-expression */:
-            break;
-
-        case DEVICE_CTRL_GET_CONFIG /* constant-expression */:
-            break;
-
-        case DEVICE_CTRL_USB_DC_SET_ADDR /* constant-expression */:
-            USB_Set_Device_Addr(((uint32_t)args) & 0x7f);
-            return 0;
-
         case DEVICE_CTRL_USB_DC_SET_ACK /* constant-expression */:
             USB_Set_EPx_Status(USB_EP_GET_IDX(((uint32_t)args) & 0x7f), USB_EP_STATUS_ACK);
             return 0;
-
-        case DEVICE_CTRL_USB_DC_SET_NACK /* constant-expression */:
-            USB_Set_EPx_Status(USB_EP_GET_IDX(((uint32_t)args) & 0x7f), USB_EP_STATUS_NACK);
+        case DEVICE_CTRL_USB_DC_ENUM_ON: {
+            uint32_t tmpVal;
+            tmpVal = BL_RD_REG(GLB_BASE, GLB_USB_XCVR);
+            tmpVal = BL_SET_REG_BITS_VAL(tmpVal, GLB_USB_ENUM, 1);
+            BL_WR_REG(GLB_BASE, GLB_USB_XCVR, tmpVal);
             return 0;
-
-        case DEVICE_CTRL_USB_DC_SET_STALL /* constant-expression */: {
-            uint8_t ep_idx = USB_EP_GET_IDX(((uint32_t)args) & 0x7f);
-
-            if (USB_EP_DIR_IS_OUT(((uint32_t)args) & 0x7f)) {
-                USB_Set_EPx_Status(ep_idx, USB_EP_STATUS_STALL);
-                usb_fs_device.out_ep[ep_idx].is_stalled = 1U;
-            } else {
-                USB_Set_EPx_Status(ep_idx, USB_EP_STATUS_STALL);
-                usb_fs_device.in_ep[ep_idx].is_stalled = 1U;
-            }
         }
-
+        case DEVICE_CTRL_USB_DC_ENUM_OFF: {
+            uint32_t tmpVal;
+            tmpVal = BL_RD_REG(GLB_BASE, GLB_USB_XCVR);
+            tmpVal = BL_SET_REG_BITS_VAL(tmpVal, GLB_USB_ENUM, 0);
+            BL_WR_REG(GLB_BASE, GLB_USB_XCVR, tmpVal);
             return 0;
-
-        case DEVICE_CTRL_USB_DC_CLR_STALL /* constant-expression */: {
-            uint8_t ep_idx = USB_EP_GET_IDX(((uint32_t)args) & 0x7f);
-
-            if (USB_EP_DIR_IS_OUT(((uint32_t)args) & 0x7f)) {
-                USB_Set_EPx_Status(ep_idx, USB_EP_STATUS_NSTALL);
-                usb_fs_device.out_ep[ep_idx].is_stalled = 0;
-            } else {
-                USB_Set_EPx_Status(ep_idx, USB_EP_STATUS_NSTALL);
-                usb_fs_device.in_ep[ep_idx].is_stalled = 0;
-            }
         }
-
-            return 0;
-
-        case DEVICE_CTRL_USB_DC_GET_TX_FIFO_CNT:
+        case DEVICE_CTRL_USB_DC_GET_EP_TX_FIFO_CNT:
             return USB_Get_EPx_TX_FIFO_CNT(((uint32_t)args) & 0x7f);
 
-        case DEVICE_CTRL_USB_DC_GET_RX_FIFO_CNT:
+        case DEVICE_CTRL_USB_DC_GET_EP_RX_FIFO_CNT:
             return USB_Get_EPx_RX_FIFO_CNT(((uint32_t)args) & 0x7f);
-
-        case DEVICE_CTRL_USB_DC_GET_EP_FREE:
-            return USB_Is_EPx_RDY_Free(((uint32_t)args) & 0x7f);
-
         case DEVICE_CTRL_ATTACH_TX_DMA /* constant-expression */:
             usb_device->tx_dma = (struct device *)args;
             break;
@@ -501,6 +462,19 @@ int usb_dc_register(enum usb_index_type index, const char *name, uint16_t flag)
     return device_register(dev, name, flag);
 }
 
+/**
+ * @brief Set USB device address
+ *
+ * @param[in] addr Device address
+ *
+ * @return 0 on success, negative errno code on fail.
+ */
+int usb_dc_set_dev_address(const uint8_t addr)
+{
+    USB_Set_Device_Addr(addr);
+    return 0;
+}
+
 /**
  * @brief configure and enable endpoint
  * This function sets endpoint configuration according to one specified in USB
@@ -581,6 +555,54 @@ int usb_dc_ep_open(struct device *dev, const struct usb_dc_ep_cfg *ep_cfg)
     return 0;
 }
 
+int usb_dc_ep_close(const uint8_t ep)
+{
+    return 0;
+}
+
+/**
+ * @brief Set stall condition for the selected endpoint
+ *
+ * @param[in] ep Endpoint address corresponding to the one
+ *               listed in the device configuration table
+ *
+ * @return 0 on success, negative errno code on fail.
+ */
+int usb_dc_ep_set_stall(const uint8_t ep)
+{
+    uint8_t ep_idx = USB_EP_GET_IDX(ep);
+
+    if (USB_EP_DIR_IS_OUT(ep)) {
+        USB_Set_EPx_Status(ep_idx, USB_EP_STATUS_STALL);
+        usb_fs_device.out_ep[ep_idx].is_stalled = 1U;
+    } else {
+        USB_Set_EPx_Status(ep_idx, USB_EP_STATUS_STALL);
+        usb_fs_device.in_ep[ep_idx].is_stalled = 1U;
+    }
+    return 0;
+}
+/**
+ * @brief Clear stall condition for the selected endpoint
+ *
+ * @param[in] ep Endpoint address corresponding to the one
+ *               listed in the device configuration table
+ *
+ * @return 0 on success, negative errno code on fail.
+ */
+int usb_dc_ep_clear_stall(const uint8_t ep)
+{
+    uint8_t ep_idx = USB_EP_GET_IDX(ep);
+
+    if (USB_EP_DIR_IS_OUT(ep)) {
+        USB_Set_EPx_Status(ep_idx, USB_EP_STATUS_NSTALL);
+        usb_fs_device.out_ep[ep_idx].is_stalled = 0;
+    } else {
+        USB_Set_EPx_Status(ep_idx, USB_EP_STATUS_NSTALL);
+        usb_fs_device.in_ep[ep_idx].is_stalled = 0;
+    }
+    return 0;
+}
+
 /**
  * @brief Check if the selected endpoint is stalled
  *
@@ -643,12 +665,12 @@ int usb_dc_ep_write(struct device *dev, const uint8_t ep, const uint8_t *data, u
 
     /* Check if IN ep */
     if (USB_EP_GET_DIR(ep) != USB_EP_DIR_IN) {
-        return -1;
+        return -USB_DC_EP_DIR_ERR;
     }
 
     /* Check if ep enabled */
     if (!usb_ep_is_enabled(ep)) {
-        return -2;
+        return -USB_DC_EP_EN_ERR;
     }
 
     while (!USB_Is_EPx_RDY_Free(ep_idx)) {
@@ -656,21 +678,20 @@ int usb_dc_ep_write(struct device *dev, const uint8_t ep, const uint8_t *data, u
 
         if (!timeout) {
             USB_DC_LOG_ERR("ep%d wait free timeout\r\n", ep);
-            return -3;
+            return -USB_DC_EP_TIMEOUT_ERR;
         }
     }
 
-    // key = irq_lock();
-    if (!data) {
-        if (!data_len) {
-            /* Zero length packet */
-            /* Clear NAK and enable ep */
-            USB_Set_EPx_Status(USB_EP_GET_IDX(ep), USB_EP_STATUS_ACK);
-            return 0;
-        } else {
-            USB_DC_LOG_ERR("data is null\r\n");
-            return -4;
-        }
+    if (!data_len) {
+        /* Zero length packet */
+        /* Clear NAK and enable ep */
+        USB_Set_EPx_Status(USB_EP_GET_IDX(ep), USB_EP_STATUS_ACK);
+        return USB_DC_OK;
+    }
+
+    if (!data && data_len) {
+        USB_DC_LOG_ERR("data is null\r\n");
+        return -USB_DC_ADDR_ERR;
     }
 
     if (data_len > usb_fs_device.in_ep[ep_idx].ep_cfg.ep_mps) {
@@ -716,7 +737,7 @@ int usb_dc_ep_write(struct device *dev, const uint8_t ep, const uint8_t *data, u
         *ret_bytes = data_len;
     }
 
-    return 0;
+    return USB_DC_OK;
 }
 
 /**
@@ -748,13 +769,13 @@ int usb_dc_ep_read(struct device *dev, const uint8_t ep, uint8_t *data, uint32_t
     /* Check if OUT ep */
     if (USB_EP_GET_DIR(ep) != USB_EP_DIR_OUT) {
         USB_DC_LOG_ERR("Wrong endpoint direction\r\n");
-        return -1;
+        return -USB_DC_EP_DIR_ERR;
     }
 
     /* Check if ep enabled */
     if (!usb_ep_is_enabled(ep)) {
         USB_DC_LOG_ERR("Not enabled endpoint\r\n");
-        return -1;
+        return -USB_DC_EP_EN_ERR;
     }
 
     /*common process for other ep out*/
@@ -784,7 +805,12 @@ int usb_dc_ep_read(struct device *dev, const uint8_t ep, uint8_t *data, uint32_t
     if (!data_len) {
         /* Clear NAK and enable ep */
         USB_Set_EPx_Status(USB_EP_GET_IDX(ep), USB_EP_STATUS_ACK);
-        return 0;
+        return USB_DC_OK;
+    }
+
+    if (!data && data_len) {
+        USB_DC_LOG_ERR("data is null\r\n");
+        return -USB_DC_ADDR_ERR;
     }
 
     read_count = USB_Get_EPx_RX_FIFO_CNT(ep_idx);
@@ -799,7 +825,7 @@ int usb_dc_ep_read(struct device *dev, const uint8_t ep, uint8_t *data, uint32_t
         *read_bytes = read_count;
     }
 
-    return 0;
+    return USB_DC_OK;
 }
 /**
  * @brief
diff --git a/drivers/bl702_driver/startup/GCC/entry.S b/drivers/bl702_driver/startup/GCC/entry.S
index 74c4ec73..3080b577 100644
--- a/drivers/bl702_driver/startup/GCC/entry.S
+++ b/drivers/bl702_driver/startup/GCC/entry.S
@@ -87,21 +87,10 @@ _enter:
     li a2, 0
     call main
 
-    /* If we've made it back here then there's probably something wrong.  We
-     * allow the METAL to register a handler here. */
-    .weak __metal_after_main
-    la ra, __metal_after_main
-    beqz ra, 1f
-    jalr ra
-1:
+    csrci mstatus, (1 << 3)
 
-    /* If that handler returns then there's not a whole lot we can do.  Just
-     * try to make some noise. */
-     la t0, 1f
-     csrw mtvec, t0
-1:
-     lw t1, 0(x0)
-     j 1b
+__exit:
+    j __exit
 
     .cfi_endproc