incubator-nuttx/wireless/bluetooth/bt_queue.h

146 lines
5.4 KiB
C

/****************************************************************************
* wireless/bluetooth/bt_queue.h
* Inter-thread buffer queue management
*
* Copyright (C) 2018 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
#ifndef __WIRELESS_BLUETOOTH_BT_QUEUE_H
#define __WIRELESS_BLUETOOTH_BT_QUEUE_H 1
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <nuttx/compiler.h>
#include <limits.h>
#include <mqueue.h>
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* Names of all POSIX message queues. */
#define BT_CONN_TX "btconntx"
#define BT_HCI_TX "bthcitx"
/* All messages are sent FIFO at the mid-message priorities except for high-
* priority messages received from the Bluetooth driver.
*/
#define BT_PRIO_MAX MQ_PRIO_MAX
#define BT_PRIO_MIN 0
#define BT_NORMAL_PRIO (BT_PRIO_MIN + (BT_PRIO_MAX - BT_PRIO_MIN) / 2)
#define BT_HIGH_PRIO (BT_PRIO_MIN + 3 * (BT_PRIO_MAX - BT_PRIO_MIN) / 4)
/* Verify that enough messages have been allocated */
#define BT_NMSGS (CONFIG_BLUETOOTH_TXCMD_NMSGS + \
CONFIG_BLUETOOTH_TXCONN_NMSGS)
#if BT_NMSGS > CONFIG_PREALLOC_MQ_MSGS
# warning WARNING: not enough pre-allocated messages
#endif
/****************************************************************************
* Public Function Prototypes
****************************************************************************/
struct bt_buf_s; /* Forward Reference */
/****************************************************************************
* Name: bt_queue_open
*
* Description:
* Open a message queue for read or write access.
*
* Input Parameters:
* name - The name of the message queue to open
* oflags - Open flags with access mode
* nmsgs - Max number of messages in queue before bt_queue_send() blocks.
* mqd - The location in which to return the message queue descriptor
*
* Returned Value:
* Zero is returned on success; a negated errno value is returned on any
* failure;
*
****************************************************************************/
int bt_queue_open(FAR const char *name, int oflags, int nmsgs,
FAR mqd_t *mqd);
/****************************************************************************
* Name: bt_queue_receive
*
* Description:
* Block until the next buffer is received on the queue.
*
* Input Parameters:
* mqd - The message queue descriptor previously returned by bt_open_*queue.
* buf - The location in which to return the received buffer.
*
* Returned Value:
* Zero is returned on success; a negated errno value is returned on any
* failure;
*
****************************************************************************/
int bt_queue_receive(mqd_t mqd, FAR struct bt_buf_s **buf);
/****************************************************************************
* Name: bt_queue_send
*
* Description:
* Send the buffer to the specified message queue
*
* Input Parameters:
* mqd - The message queue descriptor previously returned by
* bt_open_*queue.
* buf - A reference to the buffer to be sent
* priority - Either BT_NORMAL_PRIO or BT_NORMAL_HIGH. NOTE:
* BT_NORMAL_HIGHis only for use within the stack. Drivers
* should always use BT_NORMAL_PRIO.
*
* Returned Value:
* Zero is returned on success; a negated errno value is returned on any
* failure;
*
****************************************************************************/
int bt_queue_send(mqd_t mqd, FAR struct bt_buf_s *buf, unsigned int priority);
#endif /* __WIRELESS_BLUETOOTH_BT_QUEUE_H */