diff options
Diffstat (limited to 'os/hal/ports/AVR/XMEGA/LLD/SPIv1/hal_spi_lld.c')
| -rw-r--r-- | os/hal/ports/AVR/XMEGA/LLD/SPIv1/hal_spi_lld.c | 409 |
1 files changed, 409 insertions, 0 deletions
diff --git a/os/hal/ports/AVR/XMEGA/LLD/SPIv1/hal_spi_lld.c b/os/hal/ports/AVR/XMEGA/LLD/SPIv1/hal_spi_lld.c new file mode 100644 index 000000000..12c953a10 --- /dev/null +++ b/os/hal/ports/AVR/XMEGA/LLD/SPIv1/hal_spi_lld.c @@ -0,0 +1,409 @@ +/*
+ ChibiOS - Copyright (C) 2006..2018 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 SPIv1/hal_spi_lld.c
+ * @brief AVR/MEGA SPI subsystem low level driver source.
+ *
+ * @addtogroup SPI
+ * @{
+ */
+
+#include "hal.h"
+
+#if HAL_USE_SPI || defined(__DOXYGEN__)
+
+/*==========================================================================*/
+/* Driver local definitions. */
+/*==========================================================================*/
+
+#define DUMMY_SPI_SEND_VALUE 0xFF
+
+/*==========================================================================*/
+/* Driver exported variables. */
+/*==========================================================================*/
+
+/**
+ * @brief SPI1 driver identifier.
+ */
+#if AVR_SPI_USE_SPI1 || defined(__DOXYGEN__)
+SPIDriver SPID1;
+#endif
+
+/**
+ * @brief SPI2 driver identifier.
+ */
+#if AVR_SPI_USE_SPI2 || defined(__DOXYGEN__)
+SPIDriver SPID2;
+#endif
+
+/*==========================================================================*/
+/* Driver local variables and types. */
+/*==========================================================================*/
+
+/*==========================================================================*/
+/* Driver local functions. */
+/*==========================================================================*/
+/*
+// Configure the speed of the SPI interface.
+static void spi_set_speed(uint8_t ds) {
+ // We must make a test to see if we are in master mode.
+
+ // ds = double speed;
+ if (ds == SPI_SPEED_DOUBLE) {
+ SPIC.CTRL |= (1 << SPI_CLK2X_bp); // double speed.
+ }
+ else {
+ SPIC.CTRL &= ~(1 << SPI_CLK2X_bp); // simple speed.
+ }
+}
+*/
+
+
+// Enable the SPI module.
+//static void spi_lld_enable(SPIDriver *spip) {
+// spip->spi->CTRL |= (1 << SPI_ENABLE_bp);
+//}
+
+
+/*
+// Disable the SPI interface.
+static void spi_disable(void) {
+ SPIC.CTRL &= ~(1 << SPI_ENABLE_bp);
+}
+*/
+
+/*
+// Configure the SPI bit order, LSB/MSB first.
+static void spi_set_bit_order(uint8_t bo) {
+ // bo = bit order
+ if (bo == SPI_MSB_FIRST)
+ SPIC.CTRL &= ~(1 << SPI_DORD_bp);
+ else
+ SPIC.CTRL |= (1 << SPI_DORD_bp);
+}
+
+// Configure the SPI interface to Master or slave.
+static void spi_set_mode(uint8_t mode) {
+ if (mode == SPI_MODE_SLAVE)
+ SPIC.CTRL &= ~(1 << SPI_MASTER_bp);
+ else
+ SPIC.CTRL |= (1 << SPI_MASTER_bp);
+}
+
+static void spi_set_stransfer_mode(SPI_MODE_t mode) {
+ switch(mode) {
+ case SPI_TRANSFER_MODE0:
+ SPIC.CTRL = (SPIC.CTRL & ~SPI_MODE_gm) | SPI_MODE_0_gc;
+ break;
+
+ case SPI_TRANSFER_MODE1:
+ SPIC.CTRL = (SPIC.CTRL & ~SPI_MODE_gm) | SPI_MODE_1_gc;
+ break;
+
+ case SPI_TRANSFER_MODE2:
+ SPIC.CTRL = (SPIC.CTRL & ~SPI_MODE_gm) | SPI_MODE_2_gc;
+ break;
+
+ case SPI_TRANSFER_MODE3:
+ SPIC.CTRL = (SPIC.CTRL & ~SPI_MODE_gm) | SPI_MODE_3_gc;
+ break;
+
+ default:
+ SPIC.CTRL = (SPIC.CTRL & ~SPI_MODE_gm) | SPI_MODE_0_gc;
+ break;
+ }
+}*/
+
+/**
+ * @brief Configure the SPI colck from the System clock.
+ *
+ * @param[in] prescaler the prescaler used to divide the system clock
+ *//*
+static void spi_set_clock_prescaler(SPI_PRESCALER_t prescaler) {
+ switch(prescaler) {
+ case SPI_PRESCALER_4:
+ SPIC.CTRL = (SPIC.CTRL & ~SPI_PRESCALER_gm) | SPI_PRESCALER_DIV4_gc;
+ break;
+
+ case SPI_PRESCALER_16:
+ SPIC.CTRL = (SPIC.CTRL & ~SPI_PRESCALER_gm) | SPI_PRESCALER_DIV4_gc;
+ break;
+
+ case SPI_PRESCALER_64:
+ SPIC.CTRL = (SPIC.CTRL & ~SPI_PRESCALER_gm) | SPI_PRESCALER_DIV4_gc;
+ break;
+
+ case SPI_PRESCALER_128:
+ SPIC.CTRL = (SPIC.CTRL & ~SPI_PRESCALER_gm) | SPI_PRESCALER_DIV4_gc;
+ break;
+
+ default:
+ break;
+ }
+}
+*/
+
+/**
+ * @brief Enable/Disable the interruption and set the interrupt level.
+ *
+ * @param[in] il the interrupt level
+ */
+/*static void spi_set_irq_level(SPI_INTLVL_t il) {
+ switch(il) {
+ case SPI_INT_DISABLE:
+ SPIC.INTCTRL = (SPIC.INTCTRL & ~SPI_INTLVL_gm) | SPI_INTLVL_OFF_gc;
+ break;
+
+ case SPI_INT_LEVEL_LOW:
+ SPIC.INTCTRL = (SPIC.INTCTRL & ~SPI_INTLVL_gm) | SPI_INTLVL_LO_gc;
+ break;
+
+ case SPI_INT_LEVEL_MEDIUM:
+ SPIC.INTCTRL = (SPIC.INTCTRL & ~SPI_INTLVL_gm) | SPI_INTLVL_MED_gc;
+ break;
+
+ case SPI_INT_LEVEL_HIGH:
+ SPIC.INTCTRL = (SPIC.INTCTRL & ~SPI_INTLVL_gm) | SPI_INTLVL_HI_gc;
+ break;
+
+ default:
+ SPIC.INTCTRL = (SPIC.INTCTRL & ~SPI_INTLVL_gm) | SPI_INTLVL_OFF_gc;
+ break;
+ }
+}
+
+
+void spi_send_byte(uint8_t data) {
+ SPIC.DATA = data;
+ while(!(SPIC.STATUS & SPI_IF_bm));
+}
+*/
+/*
+ spi_set_speed(SPI_SPEED_SIMPLE); // Configure the speed double.
+ spi_set_bit_order(SPI_MSB_FIRST); // Configure the bit order.
+ spi_set_mode(SPI_MODE_MASTER); // Configure the mode to master.
+ spi_set_stransfer_mode(SPI_TRANSFER_MODE0); // Configure the transfer mode.
+ spi_set_clock_prescaler(SPI_PRESCALER_4); // Configure the clock prescaler.
+ spi_set_irq_level(SPI_INT_LEVEL_LOW); // Configure the irq level.
+ spi_enable(); // Enable the SPI interface.
+
+ //spi_select(); // For the chip select. // TODO
+ spi_send_byte(0xAA); // For the chip select.
+ //spi_deselect(); // for the chip select. // TODO
+ */
+/*==========================================================================*/
+/* Driver interrupt handlers. */
+/*==========================================================================*/
+
+#if AVR_SPI_USE_SPI1 || defined(__DOXYGEN__)
+/**
+ * @brief SPI event interrupt handler.
+ *
+ * @notapi
+ *//*
+OSAL_IRQ_HANDLER(SPI_STC_vect) {
+ OSAL_IRQ_PROLOGUE();
+
+ SPIDriver *spip = &SPID1;
+
+ // A new value has arrived, store it if we are interested in it.
+ if (spip->rxbuf) spip->rxbuf[spip->exidx] = SPDR;
+
+ // Check if we are done.
+ if (++(spip->exidx) >= spip->exbytes) {
+ _spi_isr_code(spip);
+ } else { // If not done send the next byte.
+ if (spip->txbuf) { // If there is a buffer with values to be send then use it.
+ SPDR = spip->txbuf[spip->exidx];
+ } else { // If there isn't a buffer with values to be send then send a the dummy value.
+ SPDR = DUMMY_SPI_SEND_VALUE;
+ }
+ }
+ OSAL_IRQ_EPILOGUE();
+}*/
+#endif /* AVR_SPI_USE_SPI1 */
+
+/*==========================================================================*/
+/* Driver exported functions. */
+/*==========================================================================*/
+
+/**
+ * @brief Low level SPI driver initialization.
+ *
+ * @notapi
+ */
+void spi_lld_init(void) {
+
+#if AVR_SPI_USE_SPI1
+ /* Driver initialization. */
+ spiObjectInit(&SPID1);
+ SPID1.spi = &SPIC;
+#endif /* AVR_SPI_USE_SPI1 */
+
+#if AVR_SPI_USE_SPI2
+ /* Driver initialization. */
+ spiObjectInit(&SPID2);
+ SPID2.spi = &SPID;
+#endif /* AVR_SPI_USE_SPI2 */
+}
+
+/**
+ * @brief Configures and activates the SPI peripheral.
+ *
+ * @param[in] spip pointer to the @p SPIDriver object
+ *
+ * @notapi
+ */
+void spi_lld_start(SPIDriver *spip) {
+
+ uint8_t dummy;
+
+ if (&SPID1 == spip) {
+ // Configures the peripheral.
+ // Note that some bits are forced:
+ // SPI interrupt disabled,
+ // SPI enabled,
+ // SPI master enabled.
+
+ spip->spi->INTCTRL = SPI_INTLVL_OFF_gc;
+
+ spip->spi->CTRL = (spip->config->clk2x ? SPI_CLK2X_bm : 0) |
+ (SPI_ENABLE_bm) |
+ (spip->config->dord ? SPI_DORD_bm : 0) |
+ (spip->config->master ? SPI_MASTER_bm : 0) |
+ (spip->config->mode) |
+ (spip->config->prescaler);
+
+ // Dummy reads before enabling interrupt.
+ dummy = spip->spi->STATUS;
+ dummy = spip->spi->DATA;
+ (void) dummy; // Suppress warning about unused variable.
+
+ // Enable SPI interrupts.
+ spip->spi->INTCTRL = spip->config->irqlevel;
+ }
+}
+
+/**
+ * @brief Deactivates the SPI peripheral.
+ *
+ * @param[in] spip pointer to the @p SPIDriver object
+ *
+ * @notapi
+ */
+void spi_lld_stop(SPIDriver *spip) {
+ if (spip->state == SPI_READY) {
+ // Disable the peripheral.
+ spip->spi->CTRL &= ~(1 << SPI_ENABLE_bp);
+ }
+}
+
+/**
+ * @brief Asserts the slave select signal and prepares for transfers.
+ *
+ * @param[in] spip pointer to the @p SPIDriver object
+ *
+ * @notapi
+ */
+void spi_lld_select(SPIDriver *spip) {
+
+ /**
+ * NOTE: This should only be called in master mode.
+ */
+ //spip->config->ssport->out &= ~(1 << spip->config->sspad);
+
+}
+
+/**
+ * @brief Deasserts the slave select signal.
+ * @details The previously selected peripheral is unselected.
+ *
+ * @param[in] spip pointer to the @p SPIDriver object
+ *
+ * @notapi
+ */
+void spi_lld_unselect(SPIDriver *spip) {
+
+ /**
+ * NOTE: This should only be called in master mode.
+ */
+ //spip->config->ssport->out |= (1 << spip->config->sspad);
+
+}
+
+
+/**
+ * @brief Exchanges data on the SPI bus.
+ * @details This asynchronous function starts a simultaneous transmit/receive
+ * operation.
+ * @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
+ *
+ * @notapi
+ */
+void spi_lld_exchange(SPIDriver *spip, size_t n, const void *txbuf, void *rxbuf) {
+
+ spip->txbuf = txbuf;
+ spip->rxbuf = rxbuf;
+ spip->exidx = 0;
+ spip->exbytes = n;
+ spip->spi->DATA = (spip->txbuf ? spip->txbuf[0] : DUMMY_SPI_SEND_VALUE);
+}
+
+
+/**
+ * @brief Exchanges one frame using a polled wait.
+ * @details This synchronous function exchanges one frame using a polled
+ * synchronization method. This function is useful when exchanging
+ * small amount of data on high speed channels, usually in this
+ * situation is much more efficient just wait for completion using
+ * polling than suspending the thread waiting for an interrupt.
+ *
+ * @param[in] spip pointer to the @p SPIDriver object
+ * @param[in] frame the data frame to send over the SPI bus
+ * @return The received data frame from the SPI bus.
+ */
+uint8_t spi_lld_polled_exchange(SPIDriver *spip, uint8_t frame) {
+
+ uint8_t spdr = 0;
+ uint8_t dummy;
+ (void)spip;
+
+ // Disable interrupt.
+ spip->spi->INTCTRL = SPI_INTLVL_OFF_gc;
+
+ spip->spi->DATA = frame;
+ while (!(spip->spi->STATUS & SPI_IF_bm)) ;
+ spdr = spip->spi->DATA;
+
+ dummy = spip->spi->STATUS;
+ dummy = spip->spi->DATA;
+ (void) dummy; // Suppress warning about unused variable.
+ spip->spi->INTCTRL = SPI_INTLVL_LO_gc;
+
+ return spdr;
+}
+
+#endif /* HAL_USE_SPI */
+
+/** @} */
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