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651 lines
19 KiB
C
651 lines
19 KiB
C
/**
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******************************************************************************
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* @addtogroup PIOS PIOS Core hardware abstraction layer
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* @{
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* @addtogroup PIOS_COM COM layer functions
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* @brief Hardware communication layer
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* @{
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*
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* @file pios_com.c
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* @author The OpenPilot Team, http://www.openpilot.org Copyright (C) 2010.
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* @brief COM layer functions
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* @see The GNU Public License (GPL) Version 3
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*
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*****************************************************************************/
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/*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 3 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful, but
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* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
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* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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* for more details.
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*
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* You should have received a copy of the GNU General Public License along
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* with this program; if not, write to the Free Software Foundation, Inc.,
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* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*/
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#include "pios.h"
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#ifdef PIOS_INCLUDE_COM
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#include "fifo_buffer.h"
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#include <pios_com_priv.h>
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#ifndef PIOS_INCLUDE_FREERTOS
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#include "pios_delay.h" /* PIOS_DELAY_WaitmS */
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#endif
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enum pios_com_dev_magic {
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PIOS_COM_DEV_MAGIC = 0xaa55aa55,
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};
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struct pios_com_dev {
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enum pios_com_dev_magic magic;
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uint32_t lower_id;
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const struct pios_com_driver *driver;
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#if defined(PIOS_INCLUDE_FREERTOS)
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xSemaphoreHandle tx_sem;
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xSemaphoreHandle rx_sem;
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xSemaphoreHandle sendbuffer_sem;
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#endif
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bool has_rx;
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bool has_tx;
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t_fifo_buffer rx;
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t_fifo_buffer tx;
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};
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static bool PIOS_COM_validate(struct pios_com_dev *com_dev)
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{
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return com_dev && (com_dev->magic == PIOS_COM_DEV_MAGIC);
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}
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#if defined(PIOS_INCLUDE_FREERTOS)
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static struct pios_com_dev *PIOS_COM_alloc(void)
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{
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struct pios_com_dev *com_dev;
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com_dev = (struct pios_com_dev *)pios_malloc(sizeof(struct pios_com_dev));
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if (!com_dev) {
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return NULL;
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}
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memset(com_dev, 0, sizeof(struct pios_com_dev));
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com_dev->magic = PIOS_COM_DEV_MAGIC;
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return com_dev;
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}
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#else
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static struct pios_com_dev pios_com_devs[PIOS_COM_MAX_DEVS];
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static uint8_t pios_com_num_devs;
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static struct pios_com_dev *PIOS_COM_alloc(void)
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{
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struct pios_com_dev *com_dev;
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if (pios_com_num_devs >= PIOS_COM_MAX_DEVS) {
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return NULL;
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}
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com_dev = &pios_com_devs[pios_com_num_devs++];
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memset(com_dev, 0, sizeof(struct pios_com_dev));
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com_dev->magic = PIOS_COM_DEV_MAGIC;
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return com_dev;
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}
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#endif /* if defined(PIOS_INCLUDE_FREERTOS) */
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static uint16_t PIOS_COM_TxOutCallback(uint32_t context, uint8_t *buf, uint16_t buf_len, uint16_t *headroom, bool *need_yield);
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static uint16_t PIOS_COM_RxInCallback(uint32_t context, uint8_t *buf, uint16_t buf_len, uint16_t *headroom, bool *need_yield);
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static void PIOS_COM_UnblockRx(struct pios_com_dev *com_dev, bool *need_yield);
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static void PIOS_COM_UnblockTx(struct pios_com_dev *com_dev, bool *need_yield);
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/**
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* Initialises COM layer
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* \param[out] handle
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* \param[in] driver
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* \param[in] id
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* \return < 0 if initialisation failed
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*/
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int32_t PIOS_COM_Init(uint32_t *com_id, const struct pios_com_driver *driver, uint32_t lower_id, uint8_t *rx_buffer, uint16_t rx_buffer_len, uint8_t *tx_buffer, uint16_t tx_buffer_len)
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{
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PIOS_Assert(com_id);
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PIOS_Assert(driver);
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bool has_rx = (rx_buffer && rx_buffer_len > 0);
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bool has_tx = (tx_buffer && tx_buffer_len > 0);
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PIOS_Assert(has_rx || has_tx);
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PIOS_Assert(driver->bind_tx_cb || !has_tx);
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PIOS_Assert(driver->bind_rx_cb || !has_rx);
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struct pios_com_dev *com_dev;
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com_dev = (struct pios_com_dev *)PIOS_COM_alloc();
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if (!com_dev) {
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goto out_fail;
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}
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com_dev->driver = driver;
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com_dev->lower_id = lower_id;
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com_dev->has_rx = has_rx;
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com_dev->has_tx = has_tx;
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if (has_rx) {
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fifoBuf_init(&com_dev->rx, rx_buffer, rx_buffer_len);
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#if defined(PIOS_INCLUDE_FREERTOS)
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vSemaphoreCreateBinary(com_dev->rx_sem);
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#endif /* PIOS_INCLUDE_FREERTOS */
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(com_dev->driver->bind_rx_cb)(lower_id, PIOS_COM_RxInCallback, (uint32_t)com_dev);
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if (com_dev->driver->rx_start) {
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/* Start the receiver */
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(com_dev->driver->rx_start)(com_dev->lower_id,
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fifoBuf_getFree(&com_dev->rx));
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}
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}
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if (has_tx) {
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fifoBuf_init(&com_dev->tx, tx_buffer, tx_buffer_len);
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#if defined(PIOS_INCLUDE_FREERTOS)
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vSemaphoreCreateBinary(com_dev->tx_sem);
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#endif /* PIOS_INCLUDE_FREERTOS */
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(com_dev->driver->bind_tx_cb)(lower_id, PIOS_COM_TxOutCallback, (uint32_t)com_dev);
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}
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#if defined(PIOS_INCLUDE_FREERTOS)
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com_dev->sendbuffer_sem = xSemaphoreCreateMutex();
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#endif /* PIOS_INCLUDE_FREERTOS */
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*com_id = (uint32_t)com_dev;
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return 0;
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out_fail:
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return -1;
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}
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#if defined(PIOS_INCLUDE_FREERTOS)
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static void PIOS_COM_UnblockRx(struct pios_com_dev *com_dev, bool *need_yield)
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{
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static signed portBASE_TYPE xHigherPriorityTaskWoken = pdFALSE;
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xSemaphoreGiveFromISR(com_dev->rx_sem, &xHigherPriorityTaskWoken);
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if (xHigherPriorityTaskWoken != pdFALSE) {
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*need_yield = true;
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} else {
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*need_yield = false;
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}
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}
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#else
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static void PIOS_COM_UnblockRx(__attribute__((unused)) struct pios_com_dev *com_dev, bool *need_yield)
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{
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*need_yield = false;
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}
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#endif
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#if defined(PIOS_INCLUDE_FREERTOS)
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static void PIOS_COM_UnblockTx(struct pios_com_dev *com_dev, bool *need_yield)
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{
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static signed portBASE_TYPE xHigherPriorityTaskWoken = pdFALSE;
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xSemaphoreGiveFromISR(com_dev->tx_sem, &xHigherPriorityTaskWoken);
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if (xHigherPriorityTaskWoken != pdFALSE) {
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*need_yield = true;
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} else {
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*need_yield = false;
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}
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}
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#else
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static void PIOS_COM_UnblockTx(__attribute__((unused)) struct pios_com_dev *com_dev, bool *need_yield)
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{
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*need_yield = false;
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}
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#endif
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static uint16_t PIOS_COM_RxInCallback(uint32_t context, uint8_t *buf, uint16_t buf_len, uint16_t *headroom, bool *need_yield)
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{
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struct pios_com_dev *com_dev = (struct pios_com_dev *)context;
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bool valid = PIOS_COM_validate(com_dev);
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PIOS_Assert(valid);
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PIOS_Assert(com_dev->has_rx);
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uint16_t bytes_into_fifo;
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if (buf_len == 1) {
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bytes_into_fifo = fifoBuf_putByte(&com_dev->rx, buf[0]);
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} else {
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bytes_into_fifo = fifoBuf_putData(&com_dev->rx, buf, buf_len);
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}
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if (bytes_into_fifo > 0) {
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/* Data has been added to the buffer */
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PIOS_COM_UnblockRx(com_dev, need_yield);
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}
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if (headroom) {
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*headroom = fifoBuf_getFree(&com_dev->rx);
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}
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return bytes_into_fifo;
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}
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static uint16_t PIOS_COM_TxOutCallback(uint32_t context, uint8_t *buf, uint16_t buf_len, uint16_t *headroom, bool *need_yield)
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{
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struct pios_com_dev *com_dev = (struct pios_com_dev *)context;
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bool valid = PIOS_COM_validate(com_dev);
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PIOS_Assert(valid);
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PIOS_Assert(buf);
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PIOS_Assert(buf_len);
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PIOS_Assert(com_dev->has_tx);
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uint16_t bytes_from_fifo = fifoBuf_getData(&com_dev->tx, buf, buf_len);
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if (bytes_from_fifo > 0) {
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/* More space has been made in the buffer */
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PIOS_COM_UnblockTx(com_dev, need_yield);
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}
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if (headroom) {
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*headroom = fifoBuf_getUsed(&com_dev->tx);
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}
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return bytes_from_fifo;
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}
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/**
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* Change the port speed without re-initializing
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* \param[in] port COM port
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* \param[in] baud Requested baud rate
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* \return -1 if port not available
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* \return 0 on success
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*/
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int32_t PIOS_COM_ChangeBaud(uint32_t com_id, uint32_t baud)
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{
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struct pios_com_dev *com_dev = (struct pios_com_dev *)com_id;
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if (!PIOS_COM_validate(com_dev)) {
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/* Undefined COM port for this board (see pios_board.c) */
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return -1;
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}
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/* Invoke the driver function if it exists */
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if (com_dev->driver->set_baud) {
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com_dev->driver->set_baud(com_dev->lower_id, baud);
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}
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return 0;
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}
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/**
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* Set control lines associated with the port
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* \param[in] port COM port
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* \param[in] mask Lines to change
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* \param[in] state New state for lines
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* \return -1 if port not available
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* \return 0 on success
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*/
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int32_t PIOS_COM_SetCtrlLine(uint32_t com_id, uint32_t mask, uint32_t state)
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{
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struct pios_com_dev *com_dev = (struct pios_com_dev *)com_id;
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if (!PIOS_COM_validate(com_dev)) {
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/* Undefined COM port for this board (see pios_board.c) */
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return -1;
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}
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/* Invoke the driver function if it exists */
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if (com_dev->driver->set_ctrl_line) {
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com_dev->driver->set_ctrl_line(com_dev->lower_id, mask, state);
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}
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return 0;
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}
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/**
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* Set control lines associated with the port
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* \param[in] port COM port
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* \param[in] ctrl_line_cb Callback function
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* \param[in] context context to pass to the callback function
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* \return -1 if port not available
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* \return 0 on success
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*/
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int32_t PIOS_COM_RegisterCtrlLineCallback(uint32_t com_id, pios_com_callback_ctrl_line ctrl_line_cb, uint32_t context)
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{
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struct pios_com_dev *com_dev = (struct pios_com_dev *)com_id;
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if (!PIOS_COM_validate(com_dev)) {
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/* Undefined COM port for this board (see pios_board.c) */
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return -1;
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}
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/* Invoke the driver function if it exists */
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if (com_dev->driver->bind_ctrl_line_cb) {
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com_dev->driver->bind_ctrl_line_cb(com_dev->lower_id, ctrl_line_cb, context);
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}
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return 0;
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}
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static int32_t PIOS_COM_SendBufferNonBlockingInternal(struct pios_com_dev *com_dev, const uint8_t *buffer, uint16_t len)
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{
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PIOS_Assert(com_dev);
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PIOS_Assert(com_dev->has_tx);
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if (com_dev->driver->available && !com_dev->driver->available(com_dev->lower_id)) {
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/*
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* Underlying device is down/unconnected.
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* Dump our fifo contents and act like an infinite data sink.
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* Failure to do this results in stale data in the fifo as well as
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* possibly having the caller block trying to send to a device that's
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* no longer accepting data.
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*/
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fifoBuf_clearData(&com_dev->tx);
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return len;
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}
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if (len > fifoBuf_getFree(&com_dev->tx)) {
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/* Buffer cannot accept all requested bytes (retry) */
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return -2;
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}
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uint16_t bytes_into_fifo = fifoBuf_putData(&com_dev->tx, buffer, len);
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if (bytes_into_fifo > 0) {
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/* More data has been put in the tx buffer, make sure the tx is started */
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if (com_dev->driver->tx_start) {
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com_dev->driver->tx_start(com_dev->lower_id,
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fifoBuf_getUsed(&com_dev->tx));
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}
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}
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return bytes_into_fifo;
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}
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/**
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* Sends a package over given port
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* \param[in] port COM port
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* \param[in] buffer character buffer
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* \param[in] len buffer length
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* \return -1 if port not available
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* \return -2 if non-blocking mode activated: buffer is full
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* caller should retry until buffer is free again
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* \return -3 another thread is already sending, caller should
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* retry until com is available again
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* \return number of bytes transmitted on success
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*/
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int32_t PIOS_COM_SendBufferNonBlocking(uint32_t com_id, const uint8_t *buffer, uint16_t len)
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{
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struct pios_com_dev *com_dev = (struct pios_com_dev *)com_id;
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if (!PIOS_COM_validate(com_dev)) {
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/* Undefined COM port for this board (see pios_board.c) */
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return -1;
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}
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#if defined(PIOS_INCLUDE_FREERTOS)
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if (xSemaphoreTake(com_dev->sendbuffer_sem, 0) != pdTRUE) {
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return -3;
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}
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#endif /* PIOS_INCLUDE_FREERTOS */
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int32_t ret = PIOS_COM_SendBufferNonBlockingInternal(com_dev, buffer, len);
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#if defined(PIOS_INCLUDE_FREERTOS)
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xSemaphoreGive(com_dev->sendbuffer_sem);
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#endif /* PIOS_INCLUDE_FREERTOS */
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return ret;
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}
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/**
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* Sends a package over given port
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* (blocking function)
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* \param[in] port COM port
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* \param[in] buffer character buffer
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* \param[in] len buffer length
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* \return -1 if port not available
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* \return -2 if mutex can't be taken;
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* \return -3 if data cannot be sent in the max allotted time of 5000msec
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* \return number of bytes transmitted on success
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*/
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int32_t PIOS_COM_SendBuffer(uint32_t com_id, const uint8_t *buffer, uint16_t len)
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{
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struct pios_com_dev *com_dev = (struct pios_com_dev *)com_id;
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if (!PIOS_COM_validate(com_dev)) {
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/* Undefined COM port for this board (see pios_board.c) */
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return -1;
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}
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PIOS_Assert(com_dev->has_tx);
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#if defined(PIOS_INCLUDE_FREERTOS)
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if (xSemaphoreTake(com_dev->sendbuffer_sem, 5) != pdTRUE) {
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return -2;
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}
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#endif /* PIOS_INCLUDE_FREERTOS */
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uint32_t max_frag_len = fifoBuf_getSize(&com_dev->tx);
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uint32_t bytes_to_send = len;
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while (bytes_to_send) {
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uint32_t frag_size;
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if (bytes_to_send > max_frag_len) {
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frag_size = max_frag_len;
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} else {
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frag_size = bytes_to_send;
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}
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int32_t rc = PIOS_COM_SendBufferNonBlockingInternal(com_dev, buffer, frag_size);
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if (rc >= 0) {
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bytes_to_send -= rc;
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buffer += rc;
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} else {
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switch (rc) {
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case -1:
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#if defined(PIOS_INCLUDE_FREERTOS)
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xSemaphoreGive(com_dev->sendbuffer_sem);
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#endif /* PIOS_INCLUDE_FREERTOS */
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/* Device is invalid, this will never work */
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return -1;
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case -2:
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/* Device is busy, wait for the underlying device to free some space and retry */
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/* Make sure the transmitter is running while we wait */
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if (com_dev->driver->tx_start) {
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(com_dev->driver->tx_start)(com_dev->lower_id,
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fifoBuf_getUsed(&com_dev->tx));
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}
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#if defined(PIOS_INCLUDE_FREERTOS)
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if (xSemaphoreTake(com_dev->tx_sem, 5000) != pdTRUE) {
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xSemaphoreGive(com_dev->sendbuffer_sem);
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return -3;
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}
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#endif
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continue;
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default:
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/* Unhandled return code */
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#if defined(PIOS_INCLUDE_FREERTOS)
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xSemaphoreGive(com_dev->sendbuffer_sem);
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#endif /* PIOS_INCLUDE_FREERTOS */
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return rc;
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}
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}
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}
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#if defined(PIOS_INCLUDE_FREERTOS)
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xSemaphoreGive(com_dev->sendbuffer_sem);
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#endif /* PIOS_INCLUDE_FREERTOS */
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return len;
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}
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/**
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* Sends a single character over given port
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* \param[in] port COM port
|
|
* \param[in] c character
|
|
* \return -1 if port not available
|
|
* \return -2 buffer is full
|
|
* caller should retry until buffer is free again
|
|
* \return 0 on success
|
|
*/
|
|
int32_t PIOS_COM_SendCharNonBlocking(uint32_t com_id, char c)
|
|
{
|
|
return PIOS_COM_SendBufferNonBlocking(com_id, (uint8_t *)&c, 1);
|
|
}
|
|
|
|
/**
|
|
* Sends a single character over given port
|
|
* (blocking function)
|
|
* \param[in] port COM port
|
|
* \param[in] c character
|
|
* \return -1 if port not available
|
|
* \return 0 on success
|
|
*/
|
|
int32_t PIOS_COM_SendChar(uint32_t com_id, char c)
|
|
{
|
|
return PIOS_COM_SendBuffer(com_id, (uint8_t *)&c, 1);
|
|
}
|
|
|
|
/**
|
|
* Sends a string over given port
|
|
* \param[in] port COM port
|
|
* \param[in] str zero-terminated string
|
|
* \return -1 if port not available
|
|
* \return -2 buffer is full
|
|
* caller should retry until buffer is free again
|
|
* \return 0 on success
|
|
*/
|
|
int32_t PIOS_COM_SendStringNonBlocking(uint32_t com_id, const char *str)
|
|
{
|
|
return PIOS_COM_SendBufferNonBlocking(com_id, (uint8_t *)str, (uint16_t)strlen(str));
|
|
}
|
|
|
|
/**
|
|
* Sends a string over given port
|
|
* (blocking function)
|
|
* \param[in] port COM port
|
|
* \param[in] str zero-terminated string
|
|
* \return -1 if port not available
|
|
* \return 0 on success
|
|
*/
|
|
int32_t PIOS_COM_SendString(uint32_t com_id, const char *str)
|
|
{
|
|
return PIOS_COM_SendBuffer(com_id, (uint8_t *)str, strlen(str));
|
|
}
|
|
|
|
/**
|
|
* Sends a formatted string (-> printf) over given port
|
|
* \param[in] port COM port
|
|
* \param[in] *format zero-terminated format string - 128 characters supported maximum!
|
|
* \param[in] ... optional arguments,
|
|
* 128 characters supported maximum!
|
|
* \return -2 if non-blocking mode activated: buffer is full
|
|
* caller should retry until buffer is free again
|
|
* \return 0 on success
|
|
*/
|
|
int32_t PIOS_COM_SendFormattedStringNonBlocking(uint32_t com_id, const char *format, ...)
|
|
{
|
|
uint8_t buffer[128]; // TODO: tmp!!! Provide a streamed COM method later!
|
|
|
|
va_list args;
|
|
|
|
va_start(args, format);
|
|
vsprintf((char *)buffer, format, args);
|
|
return PIOS_COM_SendBufferNonBlocking(com_id, buffer, (uint16_t)strlen((char *)buffer));
|
|
}
|
|
|
|
/**
|
|
* Sends a formatted string (-> printf) over given port
|
|
* (blocking function)
|
|
* \param[in] port COM port
|
|
* \param[in] *format zero-terminated format string - 128 characters supported maximum!
|
|
* \param[in] ... optional arguments,
|
|
* \return -1 if port not available
|
|
* \return 0 on success
|
|
*/
|
|
int32_t PIOS_COM_SendFormattedString(uint32_t com_id, const char *format, ...)
|
|
{
|
|
uint8_t buffer[128]; // TODO: tmp!!! Provide a streamed COM method later!
|
|
va_list args;
|
|
|
|
va_start(args, format);
|
|
vsprintf((char *)buffer, format, args);
|
|
return PIOS_COM_SendBuffer(com_id, buffer, (uint16_t)strlen((char *)buffer));
|
|
}
|
|
|
|
/**
|
|
* Transfer bytes from port buffers into another buffer
|
|
* \param[in] port COM port
|
|
* \returns Byte from buffer
|
|
*/
|
|
uint16_t PIOS_COM_ReceiveBuffer(uint32_t com_id, uint8_t *buf, uint16_t buf_len, uint32_t timeout_ms)
|
|
{
|
|
PIOS_Assert(buf);
|
|
PIOS_Assert(buf_len);
|
|
uint16_t bytes_from_fifo;
|
|
|
|
struct pios_com_dev *com_dev = (struct pios_com_dev *)com_id;
|
|
|
|
if (!PIOS_COM_validate(com_dev)) {
|
|
/* Undefined COM port for this board (see pios_board.c) */
|
|
PIOS_Assert(0);
|
|
}
|
|
PIOS_Assert(com_dev->has_rx);
|
|
|
|
check_again:
|
|
bytes_from_fifo = fifoBuf_getData(&com_dev->rx, buf, buf_len);
|
|
|
|
if (bytes_from_fifo == 0) {
|
|
/* No more bytes in receive buffer */
|
|
/* Make sure the receiver is running while we wait */
|
|
if (com_dev->driver->rx_start) {
|
|
/* Notify the lower layer that there is now room in the rx buffer */
|
|
(com_dev->driver->rx_start)(com_dev->lower_id,
|
|
fifoBuf_getFree(&com_dev->rx));
|
|
}
|
|
if (timeout_ms > 0) {
|
|
#if defined(PIOS_INCLUDE_FREERTOS)
|
|
if (xSemaphoreTake(com_dev->rx_sem, timeout_ms / portTICK_RATE_MS) == pdTRUE) {
|
|
/* Make sure we don't come back here again */
|
|
timeout_ms = 0;
|
|
goto check_again;
|
|
}
|
|
#else
|
|
PIOS_DELAY_WaitmS(1);
|
|
timeout_ms--;
|
|
goto check_again;
|
|
#endif
|
|
}
|
|
}
|
|
|
|
/* Return received byte */
|
|
return bytes_from_fifo;
|
|
}
|
|
|
|
/**
|
|
* Query if a com port is available for use. That can be
|
|
* used to check a link is established even if the device
|
|
* is valid.
|
|
*/
|
|
bool PIOS_COM_Available(uint32_t com_id)
|
|
{
|
|
struct pios_com_dev *com_dev = (struct pios_com_dev *)com_id;
|
|
|
|
if (!PIOS_COM_validate(com_dev)) {
|
|
return false;
|
|
}
|
|
|
|
// If a driver does not provide a query method assume always
|
|
// available if valid
|
|
if (com_dev->driver->available == NULL) {
|
|
return true;
|
|
}
|
|
|
|
return (com_dev->driver->available)(com_dev->lower_id);
|
|
}
|
|
|
|
#endif /* PIOS_INCLUDE_COM */
|
|
|
|
/**
|
|
* @}
|
|
* @}
|
|
*/
|