diff --git a/os/hal/platforms/AVR/platform.dox b/os/hal/platforms/AVR/platform.dox index bd6af1b1d..f012d6f66 100644 --- a/os/hal/platforms/AVR/platform.dox +++ b/os/hal/platforms/AVR/platform.dox @@ -108,3 +108,15 @@ * . * @ingroup AVR_DRIVERS */ + +/** + * @defgroup AVR_SPI AVR SPI Support + * @details The AVR SPI driver uses the SPI peripheral (USART in SPI mode + * is not supported). It is an interrupt driven implementation. + * + * @section avr_spi Supported HW resources + * The spi driver can support the following hardware resource: + * - SPI. + * . + * @ingroup AVR_DRIVERS + */ diff --git a/os/hal/platforms/AVR/platform.mk b/os/hal/platforms/AVR/platform.mk index 86a2c2eba..79e2235f0 100644 --- a/os/hal/platforms/AVR/platform.mk +++ b/os/hal/platforms/AVR/platform.mk @@ -2,7 +2,8 @@ PLATFORMSRC = ${CHIBIOS}/os/hal/platforms/AVR/hal_lld.c \ ${CHIBIOS}/os/hal/platforms/AVR/pal_lld.c \ ${CHIBIOS}/os/hal/platforms/AVR/serial_lld.c \ - ${CHIBIOS}/os/hal/platforms/AVR/i2c_lld.c + ${CHIBIOS}/os/hal/platforms/AVR/i2c_lld.c \ + ${CHIBIOS}/os/hal/platforms/AVR/spi_lld.c # Required include directories PLATFORMINC = ${CHIBIOS}/os/hal/platforms/AVR diff --git a/os/hal/platforms/AVR/spi_lld.c b/os/hal/platforms/AVR/spi_lld.c new file mode 100644 index 000000000..124411a2b --- /dev/null +++ b/os/hal/platforms/AVR/spi_lld.c @@ -0,0 +1,395 @@ +/* + ChibiOS/RT - Copyright (C) 2006,2007,2008,2009,2010, + 2011,2012,2013 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 AVR/spi_lld.c + * @brief AVR SPI subsystem low level driver source. + * + * @addtogroup SPI + * @{ + */ + +#include "ch.h" +#include "hal.h" + +#if HAL_USE_SPI || defined(__DOXYGEN__) + +/*===========================================================================*/ +/* Driver local definitions. */ +/*===========================================================================*/ + +/*===========================================================================*/ +/* Driver exported variables. */ +/*===========================================================================*/ + +/** + * @brief SPI1 driver identifier. + */ +#if USE_AVR_SPI || defined(__DOXYGEN__) +SPIDriver SPID; +#endif + +/*===========================================================================*/ +/* Driver local variables and types. */ +/*===========================================================================*/ + +/*===========================================================================*/ +/* Driver local functions. */ +/*===========================================================================*/ + +/*===========================================================================*/ +/* Driver interrupt handlers. */ +/*===========================================================================*/ + +#if USE_AVR_SPI || defined(__DOXYGEN__) +/** + * @brief SPI event interrupt handler. + * + * @notapi + */ +CH_IRQ_HANDLER(SPI_STC_vect) { + CH_IRQ_PROLOGUE(); + + SPIDriver *spip = &SPID; + + /* spi_lld_exchange */ + if (spip->rxbuf && spip->txbuf) { + spip->rxbuf[spip->rxidx++] = SPDR; + if (spip->rxidx == spip->rxbytes) { + _spi_isr_code(spip); + } else { + SPDR = spip->txbuf[spip->txidx++]; + } + /* spi_lld_send */ + } else if (spip->txbuf) { + if (spip->txidx < spip->txbytes) { + SPDR = spip->txbuf[spip->txidx++]; + } else { + _spi_isr_code(spip); + } + /* spi_lld_receive */ + } else if (spip->rxbuf) { + spip->rxbuf[spip->rxidx++] = SPDR; + if (spip->rxidx < spip->rxbytes) { + /* must keep clocking SCK */ + SPDR = 0; + } else { + _spi_isr_code(spip); + } + /* spi_lld_ignore */ + } else { + if (spip->txidx < spip->txbytes) { + SPDR = 0; + } else { + _spi_isr_code(spip); + } + } + + CH_IRQ_EPILOGUE(); +} +#endif /* USE_AVR_SPI */ + +/*===========================================================================*/ +/* Driver exported functions. */ +/*===========================================================================*/ + +/** + * @brief Low level SPI driver initialization. + * + * @notapi + */ +void spi_lld_init(void) { + +#if USE_AVR_SPI + /* Driver initialization.*/ + spiObjectInit(&SPID); +#endif /* USE_AVR_SPI */ +} + +/** + * @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; + + /* Configures the peripheral.*/ + + if (spip->state == SPI_STOP) { + /* Enables the peripheral.*/ +#if USE_AVR_SPI + if (&SPID == spip) { + /* enable SPI clock */ + PRR0 &= ~(1 << PRSPI); + + /* SPI interrupt enable, SPI enable, Master mode */ + SPCR |= ((1 << SPE) | (1 << MSTR)); + + spip->config->ssport->dir |= (1 << spip->config->sspad); + + /* XXX: For SPI to work as master, MOSI/SCK must be + * configured as outputs on your own code! + */ + + switch (spip->config->bitorder) { + case SPI_LSB_FIRST: + SPCR |= (1 << DORD); + break; + case SPI_MSB_FIRST: /* fallthrough */ + default: + SPCR &= ~(1 << DORD); + break; + } + + SPCR &= ~((1 << CPOL) | (1 << CPHA)); + switch (spip->config->mode) { + case SPI_MODE_1: + SPCR |= (1 << CPHA); + break; + case SPI_MODE_2: + SPCR |= (1 << CPOL); + break; + case SPI_MODE_3: + SPCR |= ((1 << CPOL) | (1 << CPHA)); + break; + case SPI_MODE_0: /* fallthrough */ + default: break; + } + + SPCR &= ~((1 << SPR1) | (1 << SPR0)); + SPSR &= ~(1 << SPI2X); + switch (spip->config->clockrate) { + case SPI_SCK_FOSC_2: + SPSR |= (1 << SPI2X); + break; + case SPI_SCK_FOSC_8: + SPSR |= (1 << SPI2X); + SPCR |= (1 << SPR0); + break; + case SPI_SCK_FOSC_16: + SPCR |= (1 << SPR0); + break; + case SPI_SCK_FOSC_32: + SPSR |= (1 << SPI2X); + SPCR |= (1 << SPR1); + break; + case SPI_SCK_FOSC_64: + SPCR |= (1 << SPR1); + break; + case SPI_SCK_FOSC_128: + SPCR |= ((1 << SPR1) | (1 << SPR0)); + break; + case SPI_SCK_FOSC_4: /* fallthrough */ + default: break; + } + + /* dummy reads before enabling interrupt */ + dummy = SPSR; + dummy = SPDR; + SPCR |= (1 << SPIE); + } +#endif /* USE_AVR_SPI */ + } +} + +/** + * @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) { + /* Resets the peripheral.*/ + + /* Disables the peripheral.*/ +#if USE_AVR_SPI + if (&SPID == spip) { + SPCR &= ((1 << SPIE) | (1 << SPE)); + spip->config->ssport->dir &= ~(1 << spip->config->sspad); + } +#endif /* USE_AVR_SPI */ + } +} + +/** + * @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) { + + 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) { + + spip->config->ssport->out |= (1 << spip->config->sspad); + +} + +/** + * @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. + * @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 + * + * @notapi + */ +void spi_lld_ignore(SPIDriver *spip, size_t n) { + + spip->rxbuf = spip->txbuf = NULL; + spip->txbytes = n; + spip->txidx = 0; + + SPDR = 0; +} + +/** + * @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->rxbuf = rxbuf; + spip->txbuf = txbuf; + spip->txbytes = spip->rxbytes = n; + spip->txidx = spip->rxidx = 0; + + SPDR = spip->txbuf[spip->txidx++]; +} + +/** + * @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) { + + spip->rxbuf = NULL; + spip->txbuf = txbuf; + spip->txbytes = n; + spip->txidx = 0; + + SPDR = spip->txbuf[spip->txidx++]; +} + +/** + * @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) { + + spip->txbuf = NULL; + spip->rxbuf = rxbuf; + spip->rxbytes = n; + spip->rxidx = 0; + + /* Write dummy byte to start communication */ + SPDR = 0; +} + +/** + * @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) { + + uint16_t spdr = 0; + uint8_t dummy; + + /* disable interrupt */ + SPCR &= ~(1 << SPIE); + + SPDR = frame >> 8; + while (!(SPSR & (1 << SPIF))) ; + spdr = SPDR << 8; + + SPDR = frame & 0xFF; + while (!(SPSR & (1 << SPIF))) ; + spdr |= SPDR; + + dummy = SPSR; + dummy = SPDR; + SPCR |= (1 << SPIE); + + return spdr; +} + +#endif /* HAL_USE_SPI */ + +/** @} */ diff --git a/os/hal/platforms/AVR/spi_lld.h b/os/hal/platforms/AVR/spi_lld.h new file mode 100644 index 000000000..136ca3ba1 --- /dev/null +++ b/os/hal/platforms/AVR/spi_lld.h @@ -0,0 +1,226 @@ +/* + ChibiOS/RT - Copyright (C) 2006,2007,2008,2009,2010, + 2011,2012,2013 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 AVR/spi_lld.h + * @brief AVR SPI subsystem low level driver header. + * + * @addtogroup SPI + * @{ + */ + +#ifndef _SPI_LLD_H_ +#define _SPI_LLD_H_ + +#if HAL_USE_SPI || defined(__DOXYGEN__) + +/*===========================================================================*/ +/* Driver constants. */ +/*===========================================================================*/ + +/** @brief SPI Mode (Polarity/Phase) */ +#define SPI_CPOL0_CPHA0 0 +#define SPI_CPOL0_CPHA1 1 +#define SPI_CPOL1_CPHA0 2 +#define SPI_CPOL1_CPHA1 3 + +#define SPI_MODE_0 SPI_CPOL0_CPHA0 +#define SPI_MODE_1 SPI_CPOL0_CPHA1 +#define SPI_MODE_2 SPI_CPOL1_CPHA0 +#define SPI_MODE_3 SPI_CPOL1_CPHA1 + +/** @brief Bit order */ +#define SPI_LSB_FIRST 0 +#define SPI_MSB_FIRST 1 + +/** @brief SPI clock rate FOSC/x */ +#define SPI_SCK_FOSC_2 0 +#define SPI_SCK_FOSC_4 1 +#define SPI_SCK_FOSC_8 2 +#define SPI_SCK_FOSC_16 3 +#define SPI_SCK_FOSC_32 4 +#define SPI_SCK_FOSC_64 5 +#define SPI_SCK_FOSC_128 6 + +/*===========================================================================*/ +/* Driver pre-compile time settings. */ +/*===========================================================================*/ + +/** + * @name Configuration options + * @{ + */ +/** + * @brief SPI driver enable switch. + * @details If set to @p TRUE the support for SPI1 is included. + */ +#if !defined(USE_AVR_SPI) || defined(__DOXYGEN__) +#define USE_AVR_SPI FALSE +#endif +/** @} */ + +/*===========================================================================*/ +/* Derived constants and error checks. */ +/*===========================================================================*/ + +/*===========================================================================*/ +/* Driver data structures and types. */ +/*===========================================================================*/ + +/** + * @brief Type of a structure representing an SPI driver. + */ +typedef struct SPIDriver SPIDriver; + +/** + * @brief SPI notification callback type. + * + * @param[in] spip pointer to the @p SPIDriver object triggering the + * callback + */ +typedef void (*spicallback_t)(SPIDriver *spip); + +/** + * @brief Driver configuration structure. + * @note Implementations may extend this structure to contain more, + * architecture dependent, fields. + */ +typedef struct { + /** + * @brief Port used of Slave Select + */ + ioportid_t ssport; + /** + * @brief Pad used of Slave Select + */ + uint8_t sspad; + /** + * @brief Polarity/Phase mode + */ + uint8_t mode; + /** + * @brief Use MSB/LSB first? + */ + uint8_t bitorder; + /** + * @brief Clock rate of the subsystem + */ + uint8_t clockrate; + /** + * @brief Operation complete callback. + */ + spicallback_t end_cb; + /* End of the mandatory fields.*/ +} SPIConfig; + +/** + * @brief Structure representing an SPI driver. + * @note Implementations may extend this structure to contain more, + * architecture dependent, fields. + */ +struct SPIDriver { + /** + * @brief Driver state. + */ + spistate_t state; + /** + * @brief Current configuration data. + */ + SPIConfig *config; +#if SPI_USE_WAIT || defined(__DOXYGEN__) + /** + * @brief Waiting thread. + */ + Thread *thread; +#endif /* SPI_USE_WAIT */ +#if SPI_USE_MUTUAL_EXCLUSION || defined(__DOXYGEN__) +#if CH_USE_MUTEXES || defined(__DOXYGEN__) + /** + * @brief Mutex protecting the bus. + */ + Mutex mutex; +#elif CH_USE_SEMAPHORES + Semaphore semaphore; +#endif +#endif /* SPI_USE_MUTUAL_EXCLUSION */ +#if defined(SPI_DRIVER_EXT_FIELDS) + SPI_DRIVER_EXT_FIELDS +#endif + /** + * @brief Pointer to the buffer with data to send. + */ + const uint8_t *txbuf; + /** + * @brief Number of bytes of data to send. + */ + size_t txbytes; + /** + * @brief Current index in buffer when sending data. + */ + size_t txidx; + /** + * @brief Pointer to the buffer to put received data. + */ + uint8_t *rxbuf; + /** + * @brief Number of bytes of data to receive. + */ + size_t rxbytes; + /** + * @brief Current index in buffer when receiving data. + */ + size_t rxidx; +}; + +/*===========================================================================*/ +/* Driver macros. */ +/*===========================================================================*/ + +/*===========================================================================*/ +/* External declarations. */ +/*===========================================================================*/ + +#if USE_AVR_SPI && !defined(__DOXYGEN__) +extern SPIDriver SPID; +#endif + +#ifdef __cplusplus +extern "C" { +#endif + void spi_lld_init(void); + void spi_lld_start(SPIDriver *spip); + void spi_lld_stop(SPIDriver *spip); + void spi_lld_select(SPIDriver *spip); + void spi_lld_unselect(SPIDriver *spip); + void spi_lld_ignore(SPIDriver *spip, size_t n); + void spi_lld_exchange(SPIDriver *spip, size_t n, + const void *txbuf, void *rxbuf); + void spi_lld_send(SPIDriver *spip, size_t n, const void *txbuf); + void spi_lld_receive(SPIDriver *spip, size_t n, void *rxbuf); + uint16_t spi_lld_polled_exchange(SPIDriver *spip, uint16_t frame); +#ifdef __cplusplus +} +#endif + +#endif /* HAL_USE_SPI */ + +#endif /* _SPI_LLD_H_ */ + +/** @} */