tinySA/os/hal/src/spi.c

417 lines
13 KiB
C

/*
ChibiOS - Copyright (C) 2006..2015 Giovanni Di Sirio
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
/**
* @file spi.c
* @brief SPI Driver code.
*
* @addtogroup SPI
* @{
*/
#include "hal.h"
#if (HAL_USE_SPI == TRUE) || defined(__DOXYGEN__)
/*===========================================================================*/
/* Driver local definitions. */
/*===========================================================================*/
/*===========================================================================*/
/* Driver exported variables. */
/*===========================================================================*/
/*===========================================================================*/
/* Driver local variables and types. */
/*===========================================================================*/
/*===========================================================================*/
/* Driver local functions. */
/*===========================================================================*/
/*===========================================================================*/
/* Driver exported functions. */
/*===========================================================================*/
/**
* @brief SPI Driver initialization.
* @note This function is implicitly invoked by @p halInit(), there is
* no need to explicitly initialize the driver.
*
* @init
*/
void spiInit(void) {
spi_lld_init();
}
/**
* @brief Initializes the standard part of a @p SPIDriver structure.
*
* @param[out] spip pointer to the @p SPIDriver object
*
* @init
*/
void spiObjectInit(SPIDriver *spip) {
spip->state = SPI_STOP;
spip->config = NULL;
#if SPI_USE_WAIT == TRUE
spip->thread = NULL;
#endif
#if SPI_USE_MUTUAL_EXCLUSION == TRUE
osalMutexObjectInit(&spip->mutex);
#endif
#if defined(SPI_DRIVER_EXT_INIT_HOOK)
SPI_DRIVER_EXT_INIT_HOOK(spip);
#endif
}
/**
* @brief Configures and activates the SPI peripheral.
*
* @param[in] spip pointer to the @p SPIDriver object
* @param[in] config pointer to the @p SPIConfig object
*
* @api
*/
void spiStart(SPIDriver *spip, const SPIConfig *config) {
osalDbgCheck((spip != NULL) && (config != NULL));
osalSysLock();
osalDbgAssert((spip->state == SPI_STOP) || (spip->state == SPI_READY),
"invalid state");
spip->config = config;
spi_lld_start(spip);
spip->state = SPI_READY;
osalSysUnlock();
}
/**
* @brief Deactivates the SPI peripheral.
* @note Deactivating the peripheral also enforces a release of the slave
* select line.
*
* @param[in] spip pointer to the @p SPIDriver object
*
* @api
*/
void spiStop(SPIDriver *spip) {
osalDbgCheck(spip != NULL);
osalSysLock();
osalDbgAssert((spip->state == SPI_STOP) || (spip->state == SPI_READY),
"invalid state");
spi_lld_stop(spip);
spip->state = SPI_STOP;
osalSysUnlock();
}
/**
* @brief Asserts the slave select signal and prepares for transfers.
*
* @param[in] spip pointer to the @p SPIDriver object
*
* @api
*/
void spiSelect(SPIDriver *spip) {
osalDbgCheck(spip != NULL);
osalSysLock();
osalDbgAssert(spip->state == SPI_READY, "not ready");
spiSelectI(spip);
osalSysUnlock();
}
/**
* @brief Deasserts the slave select signal.
* @details The previously selected peripheral is unselected.
*
* @param[in] spip pointer to the @p SPIDriver object
*
* @api
*/
void spiUnselect(SPIDriver *spip) {
osalDbgCheck(spip != NULL);
osalSysLock();
osalDbgAssert(spip->state == SPI_READY, "not ready");
spiUnselectI(spip);
osalSysUnlock();
}
/**
* @brief Ignores data on the SPI bus.
* @details This asynchronous function starts the transmission of a series of
* idle words on the SPI bus and ignores the received data.
* @pre A slave must have been selected using @p spiSelect() or
* @p spiSelectI().
* @post At the end of the operation the configured callback is invoked.
*
* @param[in] spip pointer to the @p SPIDriver object
* @param[in] n number of words to be ignored
*
* @api
*/
void spiStartIgnore(SPIDriver *spip, size_t n) {
osalDbgCheck((spip != NULL) && (n > 0U));
osalSysLock();
osalDbgAssert(spip->state == SPI_READY, "not ready");
spiStartIgnoreI(spip, n);
osalSysUnlock();
}
/**
* @brief Exchanges data on the SPI bus.
* @details This asynchronous function starts a simultaneous transmit/receive
* operation.
* @pre A slave must have been selected using @p spiSelect() or
* @p spiSelectI().
* @post At the end of the operation the configured callback is invoked.
* @note The buffers are organized as uint8_t arrays for data sizes below
* or equal to 8 bits else it is organized as uint16_t arrays.
*
* @param[in] spip pointer to the @p SPIDriver object
* @param[in] n number of words to be exchanged
* @param[in] txbuf the pointer to the transmit buffer
* @param[out] rxbuf the pointer to the receive buffer
*
* @api
*/
void spiStartExchange(SPIDriver *spip, size_t n,
const void *txbuf, void *rxbuf) {
osalDbgCheck((spip != NULL) && (n > 0U) &&
(rxbuf != NULL) && (txbuf != NULL));
osalSysLock();
osalDbgAssert(spip->state == SPI_READY, "not ready");
spiStartExchangeI(spip, n, txbuf, rxbuf);
osalSysUnlock();
}
/**
* @brief Sends data over the SPI bus.
* @details This asynchronous function starts a transmit operation.
* @pre A slave must have been selected using @p spiSelect() or
* @p spiSelectI().
* @post At the end of the operation the configured callback is invoked.
* @note The buffers are organized as uint8_t arrays for data sizes below
* or equal to 8 bits else it is organized as uint16_t arrays.
*
* @param[in] spip pointer to the @p SPIDriver object
* @param[in] n number of words to send
* @param[in] txbuf the pointer to the transmit buffer
*
* @api
*/
void spiStartSend(SPIDriver *spip, size_t n, const void *txbuf) {
osalDbgCheck((spip != NULL) && (n > 0U) && (txbuf != NULL));
osalSysLock();
osalDbgAssert(spip->state == SPI_READY, "not ready");
spiStartSendI(spip, n, txbuf);
osalSysUnlock();
}
/**
* @brief Receives data from the SPI bus.
* @details This asynchronous function starts a receive operation.
* @pre A slave must have been selected using @p spiSelect() or
* @p spiSelectI().
* @post At the end of the operation the configured callback is invoked.
* @note The buffers are organized as uint8_t arrays for data sizes below
* or equal to 8 bits else it is organized as uint16_t arrays.
*
* @param[in] spip pointer to the @p SPIDriver object
* @param[in] n number of words to receive
* @param[out] rxbuf the pointer to the receive buffer
*
* @api
*/
void spiStartReceive(SPIDriver *spip, size_t n, void *rxbuf) {
osalDbgCheck((spip != NULL) && (n > 0U) && (rxbuf != NULL));
osalSysLock();
osalDbgAssert(spip->state == SPI_READY, "not ready");
spiStartReceiveI(spip, n, rxbuf);
osalSysUnlock();
}
#if (SPI_USE_WAIT == TRUE) || defined(__DOXYGEN__)
/**
* @brief Ignores data on the SPI bus.
* @details This synchronous function performs the transmission of a series of
* idle words on the SPI bus and ignores the received data.
* @pre In order to use this function the option @p SPI_USE_WAIT must be
* enabled.
* @pre In order to use this function the driver must have been configured
* without callbacks (@p end_cb = @p NULL).
*
* @param[in] spip pointer to the @p SPIDriver object
* @param[in] n number of words to be ignored
*
* @api
*/
void spiIgnore(SPIDriver *spip, size_t n) {
osalDbgCheck((spip != NULL) && (n > 0U));
osalSysLock();
osalDbgAssert(spip->state == SPI_READY, "not ready");
osalDbgAssert(spip->config->end_cb == NULL, "has callback");
spiStartIgnoreI(spip, n);
(void) osalThreadSuspendS(&spip->thread);
osalSysUnlock();
}
/**
* @brief Exchanges data on the SPI bus.
* @details This synchronous function performs a simultaneous transmit/receive
* operation.
* @pre In order to use this function the option @p SPI_USE_WAIT must be
* enabled.
* @pre In order to use this function the driver must have been configured
* without callbacks (@p end_cb = @p NULL).
* @note The buffers are organized as uint8_t arrays for data sizes below
* or equal to 8 bits else it is organized as uint16_t arrays.
*
* @param[in] spip pointer to the @p SPIDriver object
* @param[in] n number of words to be exchanged
* @param[in] txbuf the pointer to the transmit buffer
* @param[out] rxbuf the pointer to the receive buffer
*
* @api
*/
void spiExchange(SPIDriver *spip, size_t n,
const void *txbuf, void *rxbuf) {
osalDbgCheck((spip != NULL) && (n > 0U) &&
(rxbuf != NULL) && (txbuf != NULL));
osalSysLock();
osalDbgAssert(spip->state == SPI_READY, "not ready");
osalDbgAssert(spip->config->end_cb == NULL, "has callback");
spiStartExchangeI(spip, n, txbuf, rxbuf);
(void) osalThreadSuspendS(&spip->thread);
osalSysUnlock();
}
/**
* @brief Sends data over the SPI bus.
* @details This synchronous function performs a transmit operation.
* @pre In order to use this function the option @p SPI_USE_WAIT must be
* enabled.
* @pre In order to use this function the driver must have been configured
* without callbacks (@p end_cb = @p NULL).
* @note The buffers are organized as uint8_t arrays for data sizes below
* or equal to 8 bits else it is organized as uint16_t arrays.
*
* @param[in] spip pointer to the @p SPIDriver object
* @param[in] n number of words to send
* @param[in] txbuf the pointer to the transmit buffer
*
* @api
*/
void spiSend(SPIDriver *spip, size_t n, const void *txbuf) {
osalDbgCheck((spip != NULL) && (n > 0U) && (txbuf != NULL));
osalSysLock();
osalDbgAssert(spip->state == SPI_READY, "not ready");
osalDbgAssert(spip->config->end_cb == NULL, "has callback");
spiStartSendI(spip, n, txbuf);
(void) osalThreadSuspendS(&spip->thread);
osalSysUnlock();
}
/**
* @brief Receives data from the SPI bus.
* @details This synchronous function performs a receive operation.
* @pre In order to use this function the option @p SPI_USE_WAIT must be
* enabled.
* @pre In order to use this function the driver must have been configured
* without callbacks (@p end_cb = @p NULL).
* @note The buffers are organized as uint8_t arrays for data sizes below
* or equal to 8 bits else it is organized as uint16_t arrays.
*
* @param[in] spip pointer to the @p SPIDriver object
* @param[in] n number of words to receive
* @param[out] rxbuf the pointer to the receive buffer
*
* @api
*/
void spiReceive(SPIDriver *spip, size_t n, void *rxbuf) {
osalDbgCheck((spip != NULL) && (n > 0U) && (rxbuf != NULL));
osalSysLock();
osalDbgAssert(spip->state == SPI_READY, "not ready");
osalDbgAssert(spip->config->end_cb == NULL, "has callback");
spiStartReceiveI(spip, n, rxbuf);
(void) osalThreadSuspendS(&spip->thread);
osalSysUnlock();
}
#endif /* SPI_USE_WAIT == TRUE */
#if (SPI_USE_MUTUAL_EXCLUSION == TRUE) || defined(__DOXYGEN__)
/**
* @brief Gains exclusive access to the SPI bus.
* @details This function tries to gain ownership to the SPI bus, if the bus
* is already being used then the invoking thread is queued.
* @pre In order to use this function the option @p SPI_USE_MUTUAL_EXCLUSION
* must be enabled.
*
* @param[in] spip pointer to the @p SPIDriver object
*
* @api
*/
void spiAcquireBus(SPIDriver *spip) {
osalDbgCheck(spip != NULL);
osalMutexLock(&spip->mutex);
}
/**
* @brief Releases exclusive access to the SPI bus.
* @pre In order to use this function the option @p SPI_USE_MUTUAL_EXCLUSION
* must be enabled.
*
* @param[in] spip pointer to the @p SPIDriver object
*
* @api
*/
void spiReleaseBus(SPIDriver *spip) {
osalDbgCheck(spip != NULL);
osalMutexUnlock(&spip->mutex);
}
#endif /* SPI_USE_MUTUAL_EXCLUSION == TRUE */
#endif /* HAL_USE_SPI == TRUE */
/** @} */