zephyr/include/bluetooth/buf.h

99 lines
2.5 KiB
C

/** @file
* @brief Bluetooth data buffer API
*/
/*
* Copyright (c) 2016 Intel Corporation
*
* SPDX-License-Identifier: Apache-2.0
*/
#ifndef ZEPHYR_INCLUDE_BLUETOOTH_BUF_H_
#define ZEPHYR_INCLUDE_BLUETOOTH_BUF_H_
/**
* @brief Data buffers
* @defgroup bt_buf Data buffers
* @ingroup bluetooth
* @{
*/
#include <zephyr/types.h>
#include <net/buf.h>
#include <bluetooth/hci.h>
/** Possible types of buffers passed around the Bluetooth stack */
enum bt_buf_type {
/** HCI command */
BT_BUF_CMD,
/** HCI event */
BT_BUF_EVT,
/** Outgoing ACL data */
BT_BUF_ACL_OUT,
/** Incoming ACL data */
BT_BUF_ACL_IN,
};
/** Minimum amount of user data size for buffers passed to the stack. */
#define BT_BUF_USER_DATA_MIN 4
/** Data size neeed for HCI RX buffers */
#define BT_BUF_RX_SIZE (CONFIG_BT_HCI_RESERVE + CONFIG_BT_RX_BUF_LEN)
/** Allocate a buffer for incoming data
*
* This will set the buffer type so bt_buf_set_type() does not need to
* be explicitly called before bt_recv_prio().
*
* @param type Type of buffer. Only BT_BUF_EVT and BT_BUF_ACL_IN are
* allowed.
* @param timeout Timeout in milliseconds, or one of the special values
* K_NO_WAIT and K_FOREVER.
* @return A new buffer.
*/
struct net_buf *bt_buf_get_rx(enum bt_buf_type type, s32_t timeout);
/** Allocate a buffer for an HCI Command Complete/Status Event
*
* This will set the buffer type so bt_buf_set_type() does not need to
* be explicitly called before bt_recv_prio().
*
* @param timeout Timeout in milliseconds, or one of the special values
* K_NO_WAIT and K_FOREVER.
* @return A new buffer.
*/
struct net_buf *bt_buf_get_cmd_complete(s32_t timeout);
/** Set the buffer type
*
* @param buf Bluetooth buffer
* @param type The BT_* type to set the buffer to
*/
static inline void bt_buf_set_type(struct net_buf *buf, enum bt_buf_type type)
{
*(u8_t *)net_buf_user_data(buf) = type;
}
/** Get the buffer type
*
* @param buf Bluetooth buffer
*
* @return The BT_* type to of the buffer
*/
static inline enum bt_buf_type bt_buf_get_type(struct net_buf *buf)
{
/* De-referencing the pointer from net_buf_user_data(buf) as a
* pointer to an enum causes issues on qemu_x86 because the true
* size is 8-bit, but the enum is 32-bit on qemu_x86. So we put in
* a temporary cast to 8-bit to ensure only 8 bits are read from
* the pointer.
*/
return (enum bt_buf_type)(*(u8_t *)net_buf_user_data(buf));
}
/**
* @}
*/
#endif /* ZEPHYR_INCLUDE_BLUETOOTH_BUF_H_ */