From 0424e11412d67f90d39bc1a9a090dfc70a1093cd Mon Sep 17 00:00:00 2001 From: theShed Date: Tue, 2 Apr 2013 14:01:52 +0000 Subject: Add os/hal/platforms/LPC8xx/spi_lld git-svn-id: svn://svn.code.sf.net/p/chibios/svn/trunk@5534 35acf78f-673a-0410-8e92-d51de3d6d3f4 --- os/hal/platforms/LPC8xx/spi_lld.c | 385 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 385 insertions(+) create mode 100644 os/hal/platforms/LPC8xx/spi_lld.c (limited to 'os/hal/platforms/LPC8xx/spi_lld.c') diff --git a/os/hal/platforms/LPC8xx/spi_lld.c b/os/hal/platforms/LPC8xx/spi_lld.c new file mode 100644 index 000000000..f9f4a9409 --- /dev/null +++ b/os/hal/platforms/LPC8xx/spi_lld.c @@ -0,0 +1,385 @@ +/* + ChibiOS/RT - Copyright (C) 2006-2013 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 LPC8xx/spi_lld.c + * @brief LPC8xx low level SPI driver code. + * + * @addtogroup SPI + * @{ + */ + +#include "ch.h" +#include "hal.h" + +#if HAL_USE_SPI || defined(__DOXYGEN__) + +/*===========================================================================*/ +/* Driver exported variables. */ +/*===========================================================================*/ + +#if LPC8xx_SPI_USE_SPI0 || defined(__DOXYGEN__) +/** @brief SPI1 driver identifier.*/ +SPIDriver SPID1; +#endif + +#if LPC8xx_SPI_USE_SPI1 || defined(__DOXYGEN__) +/** @brief SPI2 driver identifier.*/ +SPIDriver SPID2; +#endif + +/*===========================================================================*/ +/* Driver local variables and types. */ +/*===========================================================================*/ + +/*===========================================================================*/ +/* Driver local functions. */ +/*===========================================================================*/ + +static void spi_load_txdata(SPIDriver *spip) { + + LPC_SPI_TypeDef *spi = spip->spi; + + if (--spip->txcnt == 0) { + spi->TXCTRL |= SPI_TXCTRL_EOT; + } + + if (spip->txptr != NULL) { + if ((spi->TXCTRL & SPI_TXCTRL_FLEN_MASK) > SPI_TXCTRL_FLEN(8)) { + const uint16_t *p = spip->txptr; + spi->TXDAT = *p++; + spip->txptr = p; + } + else { + const uint8_t *p = spip->txptr; + spi->TXDAT = *p++; + spip->txptr = p; + } + } + else + spi->TXDAT = 0xffff; +} + +/** + * @brief Common IRQ handler. + * + * @param[in] spip pointer to the @p SPIDriver object + */ +static void spi_serve_interrupt(SPIDriver *spip) { + + LPC_SPI_TypeDef *spi = spip->spi; + + if (spi->INTSTAT & (SPI_STAT_RXOV | SPI_STAT_TXUR)) { + /* The overflow condition should never happen becausepriority is given + to receive but a hook macro is provided anyway...*/ + LPC8xx_SPI_ERROR_HOOK(spip); + spi->STAT = (SPI_STAT_RXOV | SPI_STAT_TXUR); + } + + if (spi->INTSTAT & SPI_STAT_TXRDY) { + spi_load_txdata( spip ); + } + + if (spip->txcnt == 0) { + spi->INTENCLR = (SPI_STAT_TXRDY | SPI_STAT_TXUR); + } + + if (spi->INTSTAT & SPI_STAT_RXRDY) { + if (spip->rxptr != NULL) { + if ((spi->TXCTRL & SPI_TXCTRL_FLEN_MASK) > SPI_TXCTRL_FLEN(8)) { + uint16_t *p = spip->rxptr; + *p++ = spi->RXDAT; + spip->rxptr = p; + } + else { + uint8_t *p = spip->rxptr; + *p++ = spi->RXDAT; + spip->rxptr = p; + } + } + else + (void)spi->RXDAT; + + if (--spip->rxcnt == 0) { + chDbgAssert(spip->txcnt == 0, + "spi_serve_interrupt(), #1", "counter out of synch"); + /* Stops the IRQ sources.*/ + spi->INTENCLR = (SPI_STAT_RXRDY | SPI_STAT_TXRDY | + SPI_STAT_RXOV | SPI_STAT_TXUR); + + /* Portable SPI ISR code defined in the high level driver, note, it is + a macro.*/ + _spi_isr_code(spip); + return; + } + } + +} + +/*===========================================================================*/ +/* Driver interrupt handlers. */ +/*===========================================================================*/ + +#if LPC8xx_SPI_USE_SPI0 || defined(__DOXYGEN__) +/** + * @brief SPI0 interrupt handler. + * + * @isr + */ +CH_IRQ_HANDLER(Vector40) { + + CH_IRQ_PROLOGUE(); + spi_serve_interrupt(&SPID1); + CH_IRQ_EPILOGUE(); +} +#endif + +#if LPC8xx_SPI_USE_SPI1 || defined(__DOXYGEN__) +/** + * @brief SPI1 interrupt handler. + * + * @isr + */ +CH_IRQ_HANDLER(Vector44) { + + CH_IRQ_PROLOGUE(); + spi_serve_interrupt(&SPID2); + CH_IRQ_EPILOGUE(); +} +#endif + +/*===========================================================================*/ +/* Driver exported functions. */ +/*===========================================================================*/ + +/** + * @brief Low level SPI driver initialization. + * + * @notapi + */ +void spi_lld_init(void) { + +#if LPC8xx_SPI_USE_SPI0 + spiObjectInit(&SPID1); + SPID1.spi = LPC_SPI0; +#endif + +#if LPC8xx_SPI_USE_SPI1 + spiObjectInit(&SPID2); + SPID2.spi = LPC_SPI1; +#endif +} + +/** + * @brief Configures and activates the SPI peripheral. + * + * @param[in] spip pointer to the @p SPIDriver object + * + * @notapi + */ +void spi_lld_start(SPIDriver *spip) { + + if (spip->state == SPI_STOP) { +#if LPC8xx_SPI_USE_SPI0 + if (&SPID1 == spip) { + LPC_SYSCON->SYSAHBCLKCTRL |= (1<<11); + LPC_SYSCON->PRESETCTRL |= (1<<0); + spip->spi->DIV = LPC8xx_SPI_SPI0CLKDIV; + nvicEnableVector(SPI0_IRQn, + CORTEX_PRIORITY_MASK(LPC8xx_SPI_SPI0_IRQ_PRIORITY)); + } +#endif +#if LPC8xx_SPI_USE_SPI1 + if (&SPID2 == spip) { + LPC_SYSCON->SYSAHBCLKCTRL |= (1<<12); + LPC_SYSCON->PRESETCTRL |= (1<<1); + spip->spi->DIV = LPC8xx_SPI_SPI1CLKDIV; + nvicEnableVector(SPI1_IRQn, + CORTEX_PRIORITY_MASK(LPC8xx_SPI_SPI1_IRQ_PRIORITY)); + } +#endif + } + + spip->spi->DLY = spip->config->dly; + spip->spi->TXCTRL = spip->config->txctrl; + spip->spi->STAT = (SPI_STAT_RXOV | SPI_STAT_TXUR); + spip->spi->CFG = spip->config->cfg | SPI_CFG_ENABLE; +} + +/** + * @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_STOP) { + spip->spi->CFG = 0; + +#if LPC8xx_SPI_USE_SPI0 + if (&SPID1 == spip) { + nvicDisableVector(SPI0_IRQn); + LPC_SYSCON->PRESETCTRL &= ~(1<<0); + LPC_SYSCON->SYSAHBCLKCTRL &= ~(1<<11); + } +#endif + +#if LPC8xx_SPI_USE_SPI1 + if (&SPID2 == spip) { + nvicDisableVector(SPI1_IRQn); + LPC_SYSCON->PRESETCTRL &= ~(1<<1); + LPC_SYSCON->SYSAHBCLKCTRL &= ~(1<<12); + } +#endif + + } +} + +/** + * @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) { + /* Hardware controls SSEL */ + (void)spip; +} + +/** + * @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) { + /* Hardware controls SSEL */ + (void)spip; +} + +/** + * @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->rxptr = rxbuf; + spip->txptr = txbuf; + spip->rxcnt = spip->txcnt = n; + spip->spi->TXCTRL &= ~SPI_TXCTRL_EOT; + spi_load_txdata(spip); + + if (spip->txcnt == 0) + spip->spi->INTENSET = (SPI_STAT_RXRDY | SPI_STAT_RXOV); + else + spip->spi->INTENSET = (SPI_STAT_RXRDY | SPI_STAT_TXRDY | + SPI_STAT_RXOV | SPI_STAT_TXUR); + +} + +/** + * @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 + * + * @notapi + */ +void spi_lld_ignore(SPIDriver *spip, size_t n) { + + spi_lld_exchange( spip, n, NULL, NULL); +} + +/** + * @brief Sends data over the SPI bus. + * @details This asynchronous function starts a transmit 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 send + * @param[in] txbuf the pointer to the transmit buffer + * + * @notapi + */ +void spi_lld_send(SPIDriver *spip, size_t n, const void *txbuf) { + + spi_lld_exchange( spip, n, txbuf, NULL); +} + +/** + * @brief Receives data from the SPI bus. + * @details This asynchronous function starts a 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 receive + * @param[out] rxbuf the pointer to the receive buffer + * + * @notapi + */ +void spi_lld_receive(SPIDriver *spip, size_t n, void *rxbuf) { + + spi_lld_exchange( spip, n, NULL, rxbuf); +} + +/** + * @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. + */ +uint16_t spi_lld_polled_exchange(SPIDriver *spip, uint16_t frame) { + + spip->spi->TXCTRL |= SPI_TXCTRL_EOT; + spip->spi->TXDAT = frame; + while ((spip->spi->STAT & SPI_STAT_RXRDY) == 0) + ; + return (uint16_t)spip->spi->RXDAT; +} + +#endif /* HAL_USE_SPI */ + +/** @} */ -- cgit v1.2.3