diff options
Diffstat (limited to 'os/hal/src/spi.c')
| -rw-r--r-- | os/hal/src/spi.c | 262 |
1 files changed, 262 insertions, 0 deletions
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 <http://www.gnu.org/licenses/>.
+*/
+
+/**
+ * @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 */
+
+/** @} */
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