nuttx/arch/sim/src/up_uartwait.c

89 lines
3.3 KiB
C

/****************************************************************************
* arch/sim/src/up_uartwait.c
*
* Copyright (C) 20014Gregory 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.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <semaphore.h>
#include <nuttx/semaphore.h>
#include "up_internal.h"
/****************************************************************************
* Private Data
****************************************************************************/
static sem_t g_uartavail;
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: simuart_initialize
****************************************************************************/
void simuart_initialize(void)
{
/* The g_uartavail semaphore is used for signaling and, hence, should not
* have priority inheritance enabled.
*/
sem_init(&g_uartavail, 0, 0);
sem_setprotocol(&g_uartavail, SEM_PRIO_NONE);
}
/****************************************************************************
* Name: simuart_post
****************************************************************************/
void simuart_post(void)
{
sem_post(&g_uartavail);
}
/****************************************************************************
* Name: simuart_wait
****************************************************************************/
void simuart_wait(void)
{
/* Should only fail if interrupted by a signal */
while (sem_wait(&g_uartavail) < 0);
}