From 16178e1c45a76544d34ce63db37932838353637c Mon Sep 17 00:00:00 2001 From: gdisirio Date: Sat, 28 Nov 2009 12:25:35 +0000 Subject: git-svn-id: svn://svn.code.sf.net/p/chibios/svn/trunk@1333 35acf78f-673a-0410-8e92-d51de3d6d3f4 --- os/hal/src/spi.c | 262 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 262 insertions(+) create mode 100644 os/hal/src/spi.c (limited to 'os/hal/src/spi.c') diff --git a/os/hal/src/spi.c b/os/hal/src/spi.c new file mode 100644 index 000000000..8b8ea6f32 --- /dev/null +++ b/os/hal/src/spi.c @@ -0,0 +1,262 @@ +/* + ChibiOS/RT - Copyright (C) 2006-2007 Giovanni Di Sirio. + + This file is part of ChibiOS/RT. + + ChibiOS/RT is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + ChibiOS/RT is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see . +*/ + +/** + * @file spi.c + * @brief SPI Driver code. + * @addtogroup SPI + * @{ + */ + +#include "ch.h" +#include "hal.h" + +#if CH_HAL_USE_SPI + +/** + * @brief SPI Driver initialization. + */ +void spiInit(void) { + + spi_lld_init(); +} + +/** + * @brief Initializes the standard part of a @p SPIDriver structure. + * + * @param[in] spip pointer to the @p SPIDriver object + */ +void spiObjectInit(SPIDriver *spip) { + + spip->spd_state = SPI_STOP; +#if CH_USE_MUTEXES + chMtxInit(&spip->spd_mutex); +#elif CH_USE_SEMAPHORES + chSemInit(&spip->spd_semaphore, 1); +#endif + spip->spd_config = NULL; +} + +/** + * @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 + */ +void spiStart(SPIDriver *spip, const SPIConfig *config) { + + chDbgCheck((spip != NULL) && (config != NULL), "spiStart"); + + chSysLock(); + chDbgAssert((spip->spd_state == SPI_STOP) || (spip->spd_state == SPI_READY), + "spiStart(), #1", + "invalid state"); + spip->spd_config = config; + spi_lld_start(spip); + spip->spd_state = SPI_READY; + chSysUnlock(); +} + +/** + * @brief Deactivates the SPI peripheral. + * + * @param[in] spip pointer to the @p SPIDriver object + */ +void spiStop(SPIDriver *spip) { + + chDbgCheck(spip != NULL, "spiStop"); + + chSysLock(); + chDbgAssert((spip->spd_state == SPI_STOP) || (spip->spd_state == SPI_READY), + "spiStop(), #1", + "invalid state"); + spi_lld_stop(spip); + spip->spd_state = SPI_STOP; + chSysUnlock(); +} + +/** + * @brief Asserts the slave select signal and prepares for transfers. + * + * @param[in] spip pointer to the @p SPIDriver object + */ +void spiSelect(SPIDriver *spip) { + + chDbgCheck(spip != NULL, "spiSelect"); + + chSysLock(); + chDbgAssert((spip->spd_state == SPI_READY) || + (spip->spd_state == SPI_ACTIVE), + "spiSelect(), #1", + "not idle"); + spi_lld_select(spip); + spip->spd_state = SPI_ACTIVE; + chSysUnlock(); +} + +/** + * @brief Deasserts the slave select signal. + * @details The previously selected peripheral is unselected. + * + * @param[in] spip pointer to the @p SPIDriver object + */ +void spiUnselect(SPIDriver *spip) { + + chDbgCheck(spip != NULL, "spiUnselect"); + + chSysLock(); + chDbgAssert((spip->spd_state == SPI_READY) || + (spip->spd_state == SPI_ACTIVE), + "spiUnselect(), #1", + "not locked"); + spi_lld_unselect(spip); + spip->spd_state = SPI_READY; + chSysUnlock(); +} + +/** + * @brief Ignores data on the SPI bus. + * @details This function transmits a series of idle words on the SPI bus and + * ignores the received data. This function can be invoked even + * when a slave select signal has not been yet asserted. + * + * @param[in] spip pointer to the @p SPIDriver object + * @param[in] n number of words to be ignored + */ +void spiIgnore(SPIDriver *spip, size_t n) { + + chDbgCheck((spip != NULL) && (n > 0), "spiIgnore"); + chDbgAssert((spip->spd_state == SPI_READY) || (spip->spd_state == SPI_ACTIVE), + "spiIgnore(), #1", + "not active"); + + spi_lld_ignore(spip, n); +} + +/** + * @brief Exchanges data on the SPI bus. + * @details This function performs a simultaneous transmit/receive operation. + * + * @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 + * + * @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. + */ +void spiExchange(SPIDriver *spip, size_t n, const void *txbuf, void *rxbuf) { + + chDbgCheck((spip != NULL) && (n > 0) && (rxbuf != NULL) && (txbuf != NULL), + "spiExchange"); + chDbgAssert(spip->spd_state == SPI_ACTIVE, + "spiExchange(), #1", + "not active"); + + spi_lld_exchange(spip, n, txbuf, rxbuf); +} + +/** + * @brief Sends data ever the SPI bus. + * + * @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 + * + * @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. + */ +void spiSend(SPIDriver *spip, size_t n, const void *txbuf) { + + chDbgCheck((spip != NULL) && (n > 0) && (txbuf != NULL), + "spiSend"); + chDbgAssert(spip->spd_state == SPI_ACTIVE, + "spiSend(), #1", + "not active"); + + spi_lld_send(spip, n, txbuf); +} + +/** + * @brief Receives data from the SPI bus. + * + * @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 + * + * @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. + */ +void spiReceive(SPIDriver *spip, size_t n, void *rxbuf) { + + chDbgCheck((spip != NULL) && (n > 0) && (rxbuf != NULL), + "spiReceive"); + chDbgAssert(spip->spd_state == SPI_ACTIVE, + "spiReceive(), #1", + "not active"); + + spi_lld_receive(spip, n, rxbuf); +} + +#if SPI_USE_MUTUAL_EXCLUSION || 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. + * + * @param[in] spip pointer to the @p SPIDriver object + * + * @note This function is only available when the @p SPI_USE_MUTUAL_EXCLUSION + * option is set to @p TRUE. + */ +void spiAcquireBus(SPIDriver *spip) { + + chDbgCheck(spip != NULL, "spiAcquireBus"); + +#if CH_USE_MUTEXES + chMtxLock(&spip->spd_mutex); +#elif CH_USE_SEMAPHORES + chSemWait(&spip->spd_semaphore); +#endif +} + +/** + * @brief Releases exclusive access to the SPI bus. + * + * @param[in] spip pointer to the @p SPIDriver object + * + * @note This function is only available when the @p SPI_USE_MUTUAL_EXCLUSION + * option is set to @p TRUE. + */ +void spiReleaseBus(SPIDriver *spip) { + + chDbgCheck(spip != NULL, "spiReleaseBus"); + +#if CH_USE_MUTEXES + (void)spip; + chMtxUnlock(); +#elif CH_USE_SEMAPHORES + chSemSignal(&spip->spd_semaphore); +#endif +} +#endif /*SPI_USE_MUTUAL_EXCLUSION */ + +#endif /* CH_HAL_USE_SPI */ + +/** @} */ -- cgit v1.2.3