diff --git a/components/drivers/include/ipc/ringbuffer.h b/components/drivers/include/ipc/ringbuffer.h
index 70d49cfe88..4487d02c47 100644
--- a/components/drivers/include/ipc/ringbuffer.h
+++ b/components/drivers/include/ipc/ringbuffer.h
@@ -1,160 +1,89 @@
-#ifndef RINGBUFFER_H__
+/*
+ * Copyright (c) 2006-2018, RT-Thread Development Team
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ */
 #ifndef RINGBUFFER_H__
 #define RINGBUFFER_H__
-#define RINGBUFFER_H__
-
 
 #ifdef __cplusplus
-#ifdef __cplusplus
-extern "C" {
 extern "C" {
 #endif
-#endif
-
 
 #include <rtthread.h>
-#include <rtthread.h>
-
 
 /* ring buffer */
-/* ring buffer */
-struct rt_ringbuffer
 struct rt_ringbuffer
 {
-{
-    rt_uint8_t *buffer_ptr;
     rt_uint8_t *buffer_ptr;
     /* use the msb of the {read,write}_index as mirror bit. You can see this as
-    /* use the msb of the {read,write}_index as mirror bit. You can see this as
-     * if the buffer adds a virtual mirror and the pointers point either to the
      * if the buffer adds a virtual mirror and the pointers point either to the
      * normal or to the mirrored buffer. If the write_index has the same value
-     * normal or to the mirrored buffer. If the write_index has the same value
-     * with the read_index, but in a different mirror, the buffer is full.
      * with the read_index, but in a different mirror, the buffer is full.
      * While if the write_index and the read_index are the same and within the
-     * While if the write_index and the read_index are the same and within the
-     * same mirror, the buffer is empty. The ASCII art of the ringbuffer is:
      * same mirror, the buffer is empty. The ASCII art of the ringbuffer is:
      *
-     *
-     *          mirror = 0                    mirror = 1
      *          mirror = 0                    mirror = 1
      * +---+---+---+---+---+---+---+|+~~~+~~~+~~~+~~~+~~~+~~~+~~~+
-     * +---+---+---+---+---+---+---+|+~~~+~~~+~~~+~~~+~~~+~~~+~~~+
-     * | 0 | 1 | 2 | 3 | 4 | 5 | 6 ||| 0 | 1 | 2 | 3 | 4 | 5 | 6 | Full
      * | 0 | 1 | 2 | 3 | 4 | 5 | 6 ||| 0 | 1 | 2 | 3 | 4 | 5 | 6 | Full
      * +---+---+---+---+---+---+---+|+~~~+~~~+~~~+~~~+~~~+~~~+~~~+
-     * +---+---+---+---+---+---+---+|+~~~+~~~+~~~+~~~+~~~+~~~+~~~+
-     *  read_idx-^                   write_idx-^
      *  read_idx-^                   write_idx-^
      *
-     *
-     * +---+---+---+---+---+---+---+|+~~~+~~~+~~~+~~~+~~~+~~~+~~~+
      * +---+---+---+---+---+---+---+|+~~~+~~~+~~~+~~~+~~~+~~~+~~~+
      * | 0 | 1 | 2 | 3 | 4 | 5 | 6 ||| 0 | 1 | 2 | 3 | 4 | 5 | 6 | Empty
-     * | 0 | 1 | 2 | 3 | 4 | 5 | 6 ||| 0 | 1 | 2 | 3 | 4 | 5 | 6 | Empty
-     * +---+---+---+---+---+---+---+|+~~~+~~~+~~~+~~~+~~~+~~~+~~~+
      * +---+---+---+---+---+---+---+|+~~~+~~~+~~~+~~~+~~~+~~~+~~~+
      * read_idx-^ ^-write_idx
-     * read_idx-^ ^-write_idx
-     *
      *
      * The tradeoff is we could only use 32KiB of buffer for 16 bit of index.
-     * The tradeoff is we could only use 32KiB of buffer for 16 bit of index.
-     * But it should be enough for most of the cases.
      * But it should be enough for most of the cases.
      *
-     *
-     * Ref: http://en.wikipedia.org/wiki/Circular_buffer#Mirroring */
      * Ref: http://en.wikipedia.org/wiki/Circular_buffer#Mirroring */
     rt_uint16_t read_mirror : 1;
-    rt_uint16_t read_mirror : 1;
-    rt_uint16_t read_index : 15;
     rt_uint16_t read_index : 15;
     rt_uint16_t write_mirror : 1;
-    rt_uint16_t write_mirror : 1;
-    rt_uint16_t write_index : 15;
     rt_uint16_t write_index : 15;
     /* as we use msb of index as mirror bit, the size should be signed and
-    /* as we use msb of index as mirror bit, the size should be signed and
-     * could only be positive. */
      * could only be positive. */
     rt_int16_t buffer_size;
-    rt_int16_t buffer_size;
 };
-};
-
 
 enum rt_ringbuffer_state
-enum rt_ringbuffer_state
-{
 {
     RT_RINGBUFFER_EMPTY,
-    RT_RINGBUFFER_EMPTY,
-    RT_RINGBUFFER_FULL,
     RT_RINGBUFFER_FULL,
     /* half full is neither full nor empty */
-    /* half full is neither full nor empty */
-    RT_RINGBUFFER_HALFFULL,
     RT_RINGBUFFER_HALFFULL,
 };
-};
-
 
 /**
-/**
- * RingBuffer for DeviceDriver
  * RingBuffer for DeviceDriver
  *
- *
- * Please note that the ring buffer implementation of RT-Thread
  * Please note that the ring buffer implementation of RT-Thread
  * has no thread wait or resume feature.
- * has no thread wait or resume feature.
- */
  */
 void rt_ringbuffer_init(struct rt_ringbuffer *rb, rt_uint8_t *pool, rt_int16_t size);
-void rt_ringbuffer_init(struct rt_ringbuffer *rb, rt_uint8_t *pool, rt_int16_t size);
-void rt_ringbuffer_reset(struct rt_ringbuffer *rb);
 void rt_ringbuffer_reset(struct rt_ringbuffer *rb);
 rt_size_t rt_ringbuffer_put(struct rt_ringbuffer *rb, const rt_uint8_t *ptr, rt_uint16_t length);
-rt_size_t rt_ringbuffer_put(struct rt_ringbuffer *rb, const rt_uint8_t *ptr, rt_uint16_t length);
-rt_size_t rt_ringbuffer_put_force(struct rt_ringbuffer *rb, const rt_uint8_t *ptr, rt_uint16_t length);
 rt_size_t rt_ringbuffer_put_force(struct rt_ringbuffer *rb, const rt_uint8_t *ptr, rt_uint16_t length);
 rt_size_t rt_ringbuffer_putchar(struct rt_ringbuffer *rb, const rt_uint8_t ch);
-rt_size_t rt_ringbuffer_putchar(struct rt_ringbuffer *rb, const rt_uint8_t ch);
-rt_size_t rt_ringbuffer_putchar_force(struct rt_ringbuffer *rb, const rt_uint8_t ch);
 rt_size_t rt_ringbuffer_putchar_force(struct rt_ringbuffer *rb, const rt_uint8_t ch);
 rt_size_t rt_ringbuffer_get(struct rt_ringbuffer *rb, rt_uint8_t *ptr, rt_uint16_t length);
-rt_size_t rt_ringbuffer_get(struct rt_ringbuffer *rb, rt_uint8_t *ptr, rt_uint16_t length);
-rt_size_t rt_ringbuffer_getchar(struct rt_ringbuffer *rb, rt_uint8_t *ch);
 rt_size_t rt_ringbuffer_getchar(struct rt_ringbuffer *rb, rt_uint8_t *ch);
 rt_size_t rt_ringbuffer_data_len(struct rt_ringbuffer *rb);
-rt_size_t rt_ringbuffer_data_len(struct rt_ringbuffer *rb);
-
 
 #ifdef RT_USING_HEAP
-#ifdef RT_USING_HEAP
-struct rt_ringbuffer* rt_ringbuffer_create(rt_uint16_t length);
 struct rt_ringbuffer* rt_ringbuffer_create(rt_uint16_t length);
 void rt_ringbuffer_destroy(struct rt_ringbuffer *rb);
-void rt_ringbuffer_destroy(struct rt_ringbuffer *rb);
-#endif
 #endif
 
-
-rt_inline rt_uint16_t rt_ringbuffer_get_size(struct rt_ringbuffer *rb)
 rt_inline rt_uint16_t rt_ringbuffer_get_size(struct rt_ringbuffer *rb)
 {
-{
-    RT_ASSERT(rb != RT_NULL);
     RT_ASSERT(rb != RT_NULL);
     return rb->buffer_size;
-    return rb->buffer_size;
 }
-}
-
 
 /** return the size of empty space in rb */
 #define rt_ringbuffer_space_len(rb) ((rb)->buffer_size - rt_ringbuffer_data_len(rb))