/************************************************************************************ * arm/arm/src/stm32/stm32_spi.c * * Copyright (C) 2009-2013, 2016 Gregory Nutt. All rights reserved. * Author: Gregory Nutt * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * 3. Neither the name NuttX nor the names of its contributors may be * used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. * ************************************************************************************/ /************************************************************************************ * The external functions, stm32_spi1/2/3select and stm32_spi1/2/3status must be * provided by board-specific logic. They are implementations of the select * and status methods of the SPI interface defined by struct spi_ops_s (see * include/nuttx/spi/spi.h). All other methods (including stm32_spibus_initialize()) * are provided by common STM32 logic. To use this common SPI logic on your * board: * * 1. Provide logic in stm32_boardinitialize() to configure SPI chip select * pins. * 2. Provide stm32_spi1/2/3select() and stm32_spi1/2/3status() functions in your * board-specific logic. These functions will perform chip selection and * status operations using GPIOs in the way your board is configured. * 3. Add a calls to stm32_spibus_initialize() in your low level application * initialization logic * 4. The handle returned by stm32_spibus_initialize() may then be used to bind the * SPI driver to higher level logic (e.g., calling * mmcsd_spislotinitialize(), for example, will bind the SPI driver to * the SPI MMC/SD driver). * ****************************************************c********************************/ /************************************************************************************ * Included Files ************************************************************************************/ #include #include #include #include #include #include #include #include #include #include #include #include "up_internal.h" #include "up_arch.h" #include "chip.h" #include "stm32.h" #include "stm32_gpio.h" #include "stm32_dma.h" #include "stm32_spi.h" #if defined(CONFIG_STM32_SPI1) || defined(CONFIG_STM32_SPI2) || defined(CONFIG_STM32_SPI3) || \ defined(CONFIG_STM32_SPI4) || defined(CONFIG_STM32_SPI5) || defined(CONFIG_STM32_SPI6) /************************************************************************************ * Pre-processor Definitions ************************************************************************************/ /* Configuration ********************************************************************/ /* SPI interrupts */ #ifdef CONFIG_STM32_SPI_INTERRUPTS # error "Interrupt driven SPI not yet supported" #endif /* Can't have both interrupt driven SPI and SPI DMA */ #if defined(CONFIG_STM32_SPI_INTERRUPTS) && defined(CONFIG_STM32_SPI_DMA) # error "Cannot enable both interrupt mode and DMA mode for SPI" #endif /* SPI DMA priority */ #ifdef CONFIG_STM32_SPI_DMA # if defined(CONFIG_SPI_DMAPRIO) # define SPI_DMA_PRIO CONFIG_SPI_DMAPRIO # elif defined(CONFIG_STM32_STM32F10XX) || defined(CONFIG_STM32_STM32L15XX) # define SPI_DMA_PRIO DMA_CCR_PRIMED # elif defined(CONFIG_STM32_STM32F20XX) || defined(CONFIG_STM32_STM32F40XX) # define SPI_DMA_PRIO DMA_SCR_PRIMED # else # error "Unknown STM32 DMA" # endif # if defined(CONFIG_STM32_STM32F10XX) || defined(CONFIG_STM32_STM32L15XX) # if (SPI_DMA_PRIO & ~DMA_CCR_PL_MASK) != 0 # error "Illegal value for CONFIG_SPI_DMAPRIO" # endif # elif defined(CONFIG_STM32_STM32F20XX) || defined(CONFIG_STM32_STM32F40XX) # if (SPI_DMA_PRIO & ~DMA_SCR_PL_MASK) != 0 # error "Illegal value for CONFIG_SPI_DMAPRIO" # endif # else # error "Unknown STM32 DMA" # endif #endif /* DMA channel configuration */ #if defined(CONFIG_STM32_STM32F10XX) || defined(CONFIG_STM32_STM32F30XX) || \ defined(CONFIG_STM32_STM32L15XX) || defined(CONFIG_STM32_STM32F37XX) # define SPI_RXDMA16_CONFIG (SPI_DMA_PRIO|DMA_CCR_MSIZE_16BITS|DMA_CCR_PSIZE_16BITS|DMA_CCR_MINC ) # define SPI_RXDMA8_CONFIG (SPI_DMA_PRIO|DMA_CCR_MSIZE_8BITS |DMA_CCR_PSIZE_8BITS |DMA_CCR_MINC ) # define SPI_RXDMA16NULL_CONFIG (SPI_DMA_PRIO|DMA_CCR_MSIZE_8BITS |DMA_CCR_PSIZE_16BITS ) # define SPI_RXDMA8NULL_CONFIG (SPI_DMA_PRIO|DMA_CCR_MSIZE_8BITS |DMA_CCR_PSIZE_8BITS ) # define SPI_TXDMA16_CONFIG (SPI_DMA_PRIO|DMA_CCR_MSIZE_16BITS|DMA_CCR_PSIZE_16BITS|DMA_CCR_MINC|DMA_CCR_DIR) # define SPI_TXDMA8_CONFIG (SPI_DMA_PRIO|DMA_CCR_MSIZE_8BITS |DMA_CCR_PSIZE_8BITS |DMA_CCR_MINC|DMA_CCR_DIR) # define SPI_TXDMA16NULL_CONFIG (SPI_DMA_PRIO|DMA_CCR_MSIZE_8BITS |DMA_CCR_PSIZE_16BITS |DMA_CCR_DIR) # define SPI_TXDMA8NULL_CONFIG (SPI_DMA_PRIO|DMA_CCR_MSIZE_8BITS |DMA_CCR_PSIZE_8BITS |DMA_CCR_DIR) #elif defined(CONFIG_STM32_STM32F20XX) || defined(CONFIG_STM32_STM32F40XX) # define SPI_RXDMA16_CONFIG (SPI_DMA_PRIO|DMA_SCR_MSIZE_16BITS|DMA_SCR_PSIZE_16BITS|DMA_SCR_MINC|DMA_SCR_DIR_P2M) # define SPI_RXDMA8_CONFIG (SPI_DMA_PRIO|DMA_SCR_MSIZE_8BITS |DMA_SCR_PSIZE_8BITS |DMA_SCR_MINC|DMA_SCR_DIR_P2M) # define SPI_RXDMA16NULL_CONFIG (SPI_DMA_PRIO|DMA_SCR_MSIZE_8BITS |DMA_SCR_PSIZE_16BITS |DMA_SCR_DIR_P2M) # define SPI_RXDMA8NULL_CONFIG (SPI_DMA_PRIO|DMA_SCR_MSIZE_8BITS |DMA_SCR_PSIZE_8BITS |DMA_SCR_DIR_P2M) # define SPI_TXDMA16_CONFIG (SPI_DMA_PRIO|DMA_SCR_MSIZE_16BITS|DMA_SCR_PSIZE_16BITS|DMA_SCR_MINC|DMA_SCR_DIR_M2P) # define SPI_TXDMA8_CONFIG (SPI_DMA_PRIO|DMA_SCR_MSIZE_8BITS |DMA_SCR_PSIZE_8BITS |DMA_SCR_MINC|DMA_SCR_DIR_M2P) # define SPI_TXDMA16NULL_CONFIG (SPI_DMA_PRIO|DMA_SCR_MSIZE_8BITS |DMA_SCR_PSIZE_16BITS |DMA_SCR_DIR_M2P) # define SPI_TXDMA8NULL_CONFIG (SPI_DMA_PRIO|DMA_SCR_MSIZE_8BITS |DMA_SCR_PSIZE_8BITS |DMA_SCR_DIR_M2P) #else # error "Unknown STM32 DMA" #endif /************************************************************************************ * Private Types ************************************************************************************/ struct stm32_spidev_s { struct spi_dev_s spidev; /* Externally visible part of the SPI interface */ uint32_t spibase; /* SPIn base address */ uint32_t spiclock; /* Clocking for the SPI module */ #ifdef CONFIG_STM32_SPI_INTERRUPTS uint8_t spiirq; /* SPI IRQ number */ #endif #ifdef CONFIG_STM32_SPI_DMA volatile uint8_t rxresult; /* Result of the RX DMA */ volatile uint8_t txresult; /* Result of the RX DMA */ uint8_t rxch; /* The RX DMA channel number */ uint8_t txch; /* The TX DMA channel number */ DMA_HANDLE rxdma; /* DMA channel handle for RX transfers */ DMA_HANDLE txdma; /* DMA channel handle for TX transfers */ sem_t rxsem; /* Wait for RX DMA to complete */ sem_t txsem; /* Wait for TX DMA to complete */ uint32_t txccr; /* DMA control register for TX transfers */ uint32_t rxccr; /* DMA control register for RX transfers */ #endif sem_t exclsem; /* Held while chip is selected for mutual exclusion */ uint32_t frequency; /* Requested clock frequency */ uint32_t actual; /* Actual clock frequency */ int8_t nbits; /* Width of word in bits (8 or 16) */ uint8_t mode; /* Mode 0,1,2,3 */ }; /************************************************************************************ * Private Function Prototypes ************************************************************************************/ /* Helpers */ static inline uint16_t spi_getreg(FAR struct stm32_spidev_s *priv, uint8_t offset); static inline void spi_putreg(FAR struct stm32_spidev_s *priv, uint8_t offset, uint16_t value); static inline uint16_t spi_readword(FAR struct stm32_spidev_s *priv); static inline void spi_writeword(FAR struct stm32_spidev_s *priv, uint16_t byte); static inline bool spi_16bitmode(FAR struct stm32_spidev_s *priv); /* DMA support */ #ifdef CONFIG_STM32_SPI_DMA static void spi_dmarxwait(FAR struct stm32_spidev_s *priv); static void spi_dmatxwait(FAR struct stm32_spidev_s *priv); static inline void spi_dmarxwakeup(FAR struct stm32_spidev_s *priv); static inline void spi_dmatxwakeup(FAR struct stm32_spidev_s *priv); static void spi_dmarxcallback(DMA_HANDLE handle, uint8_t isr, void *arg); static void spi_dmatxcallback(DMA_HANDLE handle, uint8_t isr, void *arg); static void spi_dmarxsetup(FAR struct stm32_spidev_s *priv, FAR void *rxbuffer, FAR void *rxdummy, size_t nwords); static void spi_dmatxsetup(FAR struct stm32_spidev_s *priv, FAR const void *txbuffer, FAR const void *txdummy, size_t nwords); static inline void spi_dmarxstart(FAR struct stm32_spidev_s *priv); static inline void spi_dmatxstart(FAR struct stm32_spidev_s *priv); #endif /* SPI methods */ static int spi_lock(FAR struct spi_dev_s *dev, bool lock); static uint32_t spi_setfrequency(FAR struct spi_dev_s *dev, uint32_t frequency); static void spi_setmode(FAR struct spi_dev_s *dev, enum spi_mode_e mode); static void spi_setbits(FAR struct spi_dev_s *dev, int nbits); #ifdef CONFIG_SPI_HWFEATURES static int spi_hwfeatures(FAR struct spi_dev_s *dev, spi_hwfeatures_t features); #endif static uint16_t spi_send(FAR struct spi_dev_s *dev, uint16_t wd); static void spi_exchange(FAR struct spi_dev_s *dev, FAR const void *txbuffer, FAR void *rxbuffer, size_t nwords); #ifndef CONFIG_SPI_EXCHANGE static void spi_sndblock(FAR struct spi_dev_s *dev, FAR const void *txbuffer, size_t nwords); static void spi_recvblock(FAR struct spi_dev_s *dev, FAR void *rxbuffer, size_t nwords); #endif /* Initialization */ static void spi_bus_initialize(FAR struct stm32_spidev_s *priv); /************************************************************************************ * Private Data ************************************************************************************/ #ifdef CONFIG_STM32_SPI1 static const struct spi_ops_s g_sp1iops = { .lock = spi_lock, .select = stm32_spi1select, .setfrequency = spi_setfrequency, .setmode = spi_setmode, .setbits = spi_setbits, #ifdef CONFIG_SPI_HWFEATURES .hwfeatures = spi_hwfeatures, #endif .status = stm32_spi1status, #ifdef CONFIG_SPI_CMDDATA .cmddata = stm32_spi1cmddata, #endif .send = spi_send, #ifdef CONFIG_SPI_EXCHANGE .exchange = spi_exchange, #else .sndblock = spi_sndblock, .recvblock = spi_recvblock, #endif #ifdef CONFIG_SPI_CALLBACK .registercallback = stm32_spi1register, /* Provided externally */ #else .registercallback = 0, /* Not implemented */ #endif }; static struct stm32_spidev_s g_spi1dev = { .spidev = { &g_sp1iops }, .spibase = STM32_SPI1_BASE, .spiclock = STM32_PCLK2_FREQUENCY, #ifdef CONFIG_STM32_SPI_INTERRUPTS .spiirq = STM32_IRQ_SPI1, #endif #ifdef CONFIG_STM32_SPI_DMA .rxch = DMACHAN_SPI1_RX, .txch = DMACHAN_SPI1_TX, #endif }; #endif #ifdef CONFIG_STM32_SPI2 static const struct spi_ops_s g_sp2iops = { .lock = spi_lock, .select = stm32_spi2select, .setfrequency = spi_setfrequency, .setmode = spi_setmode, .setbits = spi_setbits, #ifdef CONFIG_SPI_HWFEATURES .hwfeatures = spi_hwfeatures, #endif .status = stm32_spi2status, #ifdef CONFIG_SPI_CMDDATA .cmddata = stm32_spi2cmddata, #endif .send = spi_send, #ifdef CONFIG_SPI_EXCHANGE .exchange = spi_exchange, #else .sndblock = spi_sndblock, .recvblock = spi_recvblock, #endif #ifdef CONFIG_SPI_CALLBACK .registercallback = stm32_spi2register, /* provided externally */ #else .registercallback = 0, /* not implemented */ #endif }; static struct stm32_spidev_s g_spi2dev = { .spidev = { &g_sp2iops }, .spibase = STM32_SPI2_BASE, .spiclock = STM32_PCLK1_FREQUENCY, #ifdef CONFIG_STM32_SPI_INTERRUPTS .spiirq = STM32_IRQ_SPI2, #endif #ifdef CONFIG_STM32_SPI_DMA .rxch = DMACHAN_SPI2_RX, .txch = DMACHAN_SPI2_TX, #endif }; #endif #ifdef CONFIG_STM32_SPI3 static const struct spi_ops_s g_sp3iops = { .lock = spi_lock, .select = stm32_spi3select, .setfrequency = spi_setfrequency, .setmode = spi_setmode, .setbits = spi_setbits, #ifdef CONFIG_SPI_HWFEATURES .hwfeatures = spi_hwfeatures, #endif .status = stm32_spi3status, #ifdef CONFIG_SPI_CMDDATA .cmddata = stm32_spi3cmddata, #endif .send = spi_send, #ifdef CONFIG_SPI_EXCHANGE .exchange = spi_exchange, #else .sndblock = spi_sndblock, .recvblock = spi_recvblock, #endif #ifdef CONFIG_SPI_CALLBACK .registercallback = stm32_spi3register, /* provided externally */ #else .registercallback = 0, /* not implemented */ #endif }; static struct stm32_spidev_s g_spi3dev = { .spidev = { &g_sp3iops }, .spibase = STM32_SPI3_BASE, .spiclock = STM32_PCLK1_FREQUENCY, #ifdef CONFIG_STM32_SPI_INTERRUPTS .spiirq = STM32_IRQ_SPI3, #endif #ifdef CONFIG_STM32_SPI_DMA .rxch = DMACHAN_SPI3_RX, .txch = DMACHAN_SPI3_TX, #endif }; #endif #ifdef CONFIG_STM32_SPI4 static const struct spi_ops_s g_sp4iops = { .lock = spi_lock, .select = stm32_spi4select, .setfrequency = spi_setfrequency, .setmode = spi_setmode, .setbits = spi_setbits, #ifdef CONFIG_SPI_HWFEATURES .hwfeatures = spi_hwfeatures, #endif .status = stm32_spi4status, #ifdef CONFIG_SPI_CMDDATA .cmddata = stm32_spi4cmddata, #endif .send = spi_send, #ifdef CONFIG_SPI_EXCHANGE .exchange = spi_exchange, #else .sndblock = spi_sndblock, .recvblock = spi_recvblock, #endif #ifdef CONFIG_SPI_CALLBACK .registercallback = stm32_spi4register, /* provided externally */ #else .registercallback = 0, /* not implemented */ #endif }; static struct stm32_spidev_s g_spi4dev = { .spidev = { &g_sp4iops }, .spibase = STM32_SPI4_BASE, .spiclock = STM32_PCLK2_FREQUENCY, #ifdef CONFIG_STM32_SPI_INTERRUPTS .spiirq = STM32_IRQ_SPI4, #endif #ifdef CONFIG_STM32_SPI_DMA .rxch = DMACHAN_SPI4_RX, .txch = DMACHAN_SPI4_TX, #endif }; #endif #ifdef CONFIG_STM32_SPI5 static const struct spi_ops_s g_sp5iops = { .lock = spi_lock, .select = stm32_spi5select, .setfrequency = spi_setfrequency, .setmode = spi_setmode, .setbits = spi_setbits, #ifdef CONFIG_SPI_HWFEATURES .hwfeatures = spi_hwfeatures, #endif .status = stm32_spi5status, #ifdef CONFIG_SPI_CMDDATA .cmddata = stm32_spi5cmddata, #endif .send = spi_send, #ifdef CONFIG_SPI_EXCHANGE .exchange = spi_exchange, #else .sndblock = spi_sndblock, .recvblock = spi_recvblock, #endif #ifdef CONFIG_SPI_CALLBACK .registercallback = stm32_spi5register, /* provided externally */ #else .registercallback = 0, /* not implemented */ #endif }; static struct stm32_spidev_s g_spi5dev = { .spidev = { &g_sp5iops }, .spibase = STM32_SPI5_BASE, .spiclock = STM32_PCLK2_FREQUENCY, #ifdef CONFIG_STM32_SPI_INTERRUPTS .spiirq = STM32_IRQ_SPI5, #endif #ifdef CONFIG_STM32_SPI_DMA .rxch = DMACHAN_SPI5_RX, .txch = DMACHAN_SPI5_TX, #endif }; #endif #ifdef CONFIG_STM32_SPI6 static const struct spi_ops_s g_sp6iops = { .lock = spi_lock, .select = stm32_spi6select, .setfrequency = spi_setfrequency, .setmode = spi_setmode, .setbits = spi_setbits, #ifdef CONFIG_SPI_HWFEATURES .hwfeatures = spi_hwfeatures, #endif .status = stm32_spi6status, #ifdef CONFIG_SPI_CMDDATA .cmddata = stm32_spi3cmddata, #endif .send = spi_send, #ifdef CONFIG_SPI_EXCHANGE .exchange = spi_exchange, #else .sndblock = spi_sndblock, .recvblock = spi_recvblock, #endif #ifdef CONFIG_SPI_CALLBACK .registercallback = stm32_spi6register, /* provided externally */ #else .registercallback = 0, /* not implemented */ #endif }; static struct stm32_spidev_s g_spi6dev = { .spidev = { &g_sp6iops }, .spibase = STM32_SPI6_BASE, .spiclock = STM32_PCLK2_FREQUENCY, #ifdef CONFIG_STM32_SPI_INTERRUPTS .spiirq = STM32_IRQ_SPI6, #endif #ifdef CONFIG_STM32_SPI_DMA .rxch = DMACHAN_SPI6_RX, .txch = DMACHAN_SPI6_TX, #endif }; #endif /************************************************************************************ * Public Data ************************************************************************************/ /************************************************************************************ * Private Functions ************************************************************************************/ /************************************************************************************ * Name: spi_getreg * * Description: * Get the contents of the SPI register at offset * * Input Parameters: * priv - private SPI device structure * offset - offset to the register of interest * * Returned Value: * The contents of the 16-bit register * ************************************************************************************/ static inline uint16_t spi_getreg(FAR struct stm32_spidev_s *priv, uint8_t offset) { return getreg16(priv->spibase + offset); } /************************************************************************************ * Name: spi_putreg * * Description: * Write a 16-bit value to the SPI register at offset * * Input Parameters: * priv - private SPI device structure * offset - offset to the register of interest * value - the 16-bit value to be written * * Returned Value: * The contents of the 16-bit register * ************************************************************************************/ static inline void spi_putreg(FAR struct stm32_spidev_s *priv, uint8_t offset, uint16_t value) { putreg16(value, priv->spibase + offset); } /************************************************************************************ * Name: spi_readword * * Description: * Read one byte from SPI * * Input Parameters: * priv - Device-specific state data * * Returned Value: * Byte as read * ************************************************************************************/ static inline uint16_t spi_readword(FAR struct stm32_spidev_s *priv) { /* Wait until the receive buffer is not empty */ while ((spi_getreg(priv, STM32_SPI_SR_OFFSET) & SPI_SR_RXNE) == 0); /* Then return the received byte */ return spi_getreg(priv, STM32_SPI_DR_OFFSET); } /************************************************************************************ * Name: spi_writeword * * Description: * Write one byte to SPI * * Input Parameters: * priv - Device-specific state data * byte - Byte to send * * Returned Value: * None * ************************************************************************************/ static inline void spi_writeword(FAR struct stm32_spidev_s *priv, uint16_t word) { /* Wait until the transmit buffer is empty */ while ((spi_getreg(priv, STM32_SPI_SR_OFFSET) & SPI_SR_TXE) == 0); /* Then send the byte */ spi_putreg(priv, STM32_SPI_DR_OFFSET, word); } /************************************************************************************ * Name: spi_16bitmode * * Description: * Check if the SPI is operating in 16-bit mode * * Input Parameters: * priv - Device-specific state data * * Returned Value: * true: 16-bit mode, false: 8-bit mode * ************************************************************************************/ static inline bool spi_16bitmode(FAR struct stm32_spidev_s *priv) { return ((spi_getreg(priv, STM32_SPI_CR1_OFFSET) & SPI_CR1_DFF) != 0); } /************************************************************************************ * Name: spi_dmarxwait * * Description: * Wait for DMA to complete. * ************************************************************************************/ #ifdef CONFIG_STM32_SPI_DMA static void spi_dmarxwait(FAR struct stm32_spidev_s *priv) { /* Take the semaphore (perhaps waiting). If the result is zero, then the DMA * must not really have completed??? */ while (sem_wait(&priv->rxsem) != 0 || priv->rxresult == 0) { /* The only case that an error should occur here is if the wait was awakened * by a signal. */ ASSERT(errno == EINTR); } } #endif /************************************************************************************ * Name: spi_dmatxwait * * Description: * Wait for DMA to complete. * ************************************************************************************/ #ifdef CONFIG_STM32_SPI_DMA static void spi_dmatxwait(FAR struct stm32_spidev_s *priv) { /* Take the semaphore (perhaps waiting). If the result is zero, then the DMA * must not really have completed??? */ while (sem_wait(&priv->txsem) != 0 || priv->txresult == 0) { /* The only case that an error should occur here is if the wait was awakened * by a signal. */ ASSERT(errno == EINTR); } } #endif /************************************************************************************ * Name: spi_dmarxwakeup * * Description: * Signal that DMA is complete * ************************************************************************************/ #ifdef CONFIG_STM32_SPI_DMA static inline void spi_dmarxwakeup(FAR struct stm32_spidev_s *priv) { (void)sem_post(&priv->rxsem); } #endif /************************************************************************************ * Name: spi_dmatxwakeup * * Description: * Signal that DMA is complete * ************************************************************************************/ #ifdef CONFIG_STM32_SPI_DMA static inline void spi_dmatxwakeup(FAR struct stm32_spidev_s *priv) { (void)sem_post(&priv->txsem); } #endif /************************************************************************************ * Name: spi_dmarxcallback * * Description: * Called when the RX DMA completes * ************************************************************************************/ #ifdef CONFIG_STM32_SPI_DMA static void spi_dmarxcallback(DMA_HANDLE handle, uint8_t isr, void *arg) { FAR struct stm32_spidev_s *priv = (FAR struct stm32_spidev_s *)arg; /* Wake-up the SPI driver */ priv->rxresult = isr | 0x080; /* OR'ed with 0x80 to assure non-zero */ spi_dmarxwakeup(priv); } #endif /************************************************************************************ * Name: spi_dmatxcallback * * Description: * Called when the RX DMA completes * ************************************************************************************/ #ifdef CONFIG_STM32_SPI_DMA static void spi_dmatxcallback(DMA_HANDLE handle, uint8_t isr, void *arg) { FAR struct stm32_spidev_s *priv = (FAR struct stm32_spidev_s *)arg; /* Wake-up the SPI driver */ priv->txresult = isr | 0x080; /* OR'ed with 0x80 to assure non-zero */ spi_dmatxwakeup(priv); } #endif /************************************************************************************ * Name: spi_dmarxsetup * * Description: * Setup to perform RX DMA * ************************************************************************************/ #ifdef CONFIG_STM32_SPI_DMA static void spi_dmarxsetup(FAR struct stm32_spidev_s *priv, FAR void *rxbuffer, FAR void *rxdummy, size_t nwords) { /* 8- or 16-bit mode? */ if (spi_16bitmode(priv)) { /* 16-bit mode -- is there a buffer to receive data in? */ if (rxbuffer) { priv->rxccr = SPI_RXDMA16_CONFIG; } else { rxbuffer = rxdummy; priv->rxccr = SPI_RXDMA16NULL_CONFIG; } } else { /* 8-bit mode -- is there a buffer to receive data in? */ if (rxbuffer) { priv->rxccr = SPI_RXDMA8_CONFIG; } else { rxbuffer = rxdummy; priv->rxccr = SPI_RXDMA8NULL_CONFIG; } } /* Configure the RX DMA */ stm32_dmasetup(priv->rxdma, priv->spibase + STM32_SPI_DR_OFFSET, (uint32_t)rxbuffer, nwords, priv->rxccr); } #endif /************************************************************************************ * Name: spi_dmatxsetup * * Description: * Setup to perform TX DMA * ************************************************************************************/ #ifdef CONFIG_STM32_SPI_DMA static void spi_dmatxsetup(FAR struct stm32_spidev_s *priv, FAR const void *txbuffer, FAR const void *txdummy, size_t nwords) { /* 8- or 16-bit mode? */ if (spi_16bitmode(priv)) { /* 16-bit mode -- is there a buffer to transfer data from? */ if (txbuffer) { priv->txccr = SPI_TXDMA16_CONFIG; } else { txbuffer = txdummy; priv->txccr = SPI_TXDMA16NULL_CONFIG; } } else { /* 8-bit mode -- is there a buffer to transfer data from? */ if (txbuffer) { priv->txccr = SPI_TXDMA8_CONFIG; } else { txbuffer = txdummy; priv->txccr = SPI_TXDMA8NULL_CONFIG; } } /* Setup the TX DMA */ stm32_dmasetup(priv->txdma, priv->spibase + STM32_SPI_DR_OFFSET, (uint32_t)txbuffer, nwords, priv->txccr); } #endif /************************************************************************************ * Name: spi_dmarxstart * * Description: * Start RX DMA * ************************************************************************************/ #ifdef CONFIG_STM32_SPI_DMA static inline void spi_dmarxstart(FAR struct stm32_spidev_s *priv) { priv->rxresult = 0; stm32_dmastart(priv->rxdma, spi_dmarxcallback, priv, false); } #endif /************************************************************************************ * Name: spi_dmatxstart * * Description: * Start TX DMA * ************************************************************************************/ #ifdef CONFIG_STM32_SPI_DMA static inline void spi_dmatxstart(FAR struct stm32_spidev_s *priv) { priv->txresult = 0; stm32_dmastart(priv->txdma, spi_dmatxcallback, priv, false); } #endif /************************************************************************************ * Name: spi_modifycr1 * * Description: * Clear and set bits in the CR1 register * * Input Parameters: * priv - Device-specific state data * clrbits - The bits to clear * setbits - The bits to set * * Returned Value: * None * ************************************************************************************/ static void spi_modifycr1(FAR struct stm32_spidev_s *priv, uint16_t setbits, uint16_t clrbits) { uint16_t cr1; cr1 = spi_getreg(priv, STM32_SPI_CR1_OFFSET); cr1 &= ~clrbits; cr1 |= setbits; spi_putreg(priv, STM32_SPI_CR1_OFFSET, cr1); } /************************************************************************************ * Name: spi_lock * * Description: * On SPI busses where there are multiple devices, it will be necessary to * lock SPI to have exclusive access to the busses for a sequence of * transfers. The bus should be locked before the chip is selected. After * locking the SPI bus, the caller should then also call the setfrequency, * setbits, and setmode methods to make sure that the SPI is properly * configured for the device. If the SPI buss is being shared, then it * may have been left in an incompatible state. * * Input Parameters: * dev - Device-specific state data * lock - true: Lock spi bus, false: unlock SPI bus * * Returned Value: * None * ************************************************************************************/ static int spi_lock(FAR struct spi_dev_s *dev, bool lock) { FAR struct stm32_spidev_s *priv = (FAR struct stm32_spidev_s *)dev; if (lock) { /* Take the semaphore (perhaps waiting) */ while (sem_wait(&priv->exclsem) != 0) { /* The only case that an error should occur here is if the wait was awakened * by a signal. */ ASSERT(errno == EINTR); } } else { (void)sem_post(&priv->exclsem); } return OK; } /************************************************************************************ * Name: spi_setfrequency * * Description: * Set the SPI frequency. * * Input Parameters: * dev - Device-specific state data * frequency - The SPI frequency requested * * Returned Value: * Returns the actual frequency selected * ************************************************************************************/ static uint32_t spi_setfrequency(FAR struct spi_dev_s *dev, uint32_t frequency) { FAR struct stm32_spidev_s *priv = (FAR struct stm32_spidev_s *)dev; uint16_t setbits; uint32_t actual; /* Limit to max possible (if STM32_SPI_CLK_MAX is defined in board.h) */ if (frequency > STM32_SPI_CLK_MAX) { frequency = STM32_SPI_CLK_MAX; } /* Has the frequency changed? */ if (frequency != priv->frequency) { /* Choices are limited by PCLK frequency with a set of divisors */ if (frequency >= priv->spiclock >> 1) { /* More than fPCLK/2. This is as fast as we can go */ setbits = SPI_CR1_FPCLCKd2; /* 000: fPCLK/2 */ actual = priv->spiclock >> 1; } else if (frequency >= priv->spiclock >> 2) { /* Between fPCLCK/2 and fPCLCK/4, pick the slower */ setbits = SPI_CR1_FPCLCKd4; /* 001: fPCLK/4 */ actual = priv->spiclock >> 2; } else if (frequency >= priv->spiclock >> 3) { /* Between fPCLCK/4 and fPCLCK/8, pick the slower */ setbits = SPI_CR1_FPCLCKd8; /* 010: fPCLK/8 */ actual = priv->spiclock >> 3; } else if (frequency >= priv->spiclock >> 4) { /* Between fPCLCK/8 and fPCLCK/16, pick the slower */ setbits = SPI_CR1_FPCLCKd16; /* 011: fPCLK/16 */ actual = priv->spiclock >> 4; } else if (frequency >= priv->spiclock >> 5) { /* Between fPCLCK/16 and fPCLCK/32, pick the slower */ setbits = SPI_CR1_FPCLCKd32; /* 100: fPCLK/32 */ actual = priv->spiclock >> 5; } else if (frequency >= priv->spiclock >> 6) { /* Between fPCLCK/32 and fPCLCK/64, pick the slower */ setbits = SPI_CR1_FPCLCKd64; /* 101: fPCLK/64 */ actual = priv->spiclock >> 6; } else if (frequency >= priv->spiclock >> 7) { /* Between fPCLCK/64 and fPCLCK/128, pick the slower */ setbits = SPI_CR1_FPCLCKd128; /* 110: fPCLK/128 */ actual = priv->spiclock >> 7; } else { /* Less than fPCLK/128. This is as slow as we can go */ setbits = SPI_CR1_FPCLCKd256; /* 111: fPCLK/256 */ actual = priv->spiclock >> 8; } spi_modifycr1(priv, 0, SPI_CR1_SPE); spi_modifycr1(priv, setbits, SPI_CR1_BR_MASK); spi_modifycr1(priv, SPI_CR1_SPE, 0); /* Save the frequency selection so that subsequent reconfigurations will be * faster. */ spiinfo("Frequency %d->%d\n", frequency, actual); priv->frequency = frequency; priv->actual = actual; } return priv->actual; } /************************************************************************************ * Name: spi_setmode * * Description: * Set the SPI mode. see enum spi_mode_e for mode definitions * * Input Parameters: * dev - Device-specific state data * mode - The SPI mode requested * * Returned Value: * Returns the actual frequency selected * ************************************************************************************/ static void spi_setmode(FAR struct spi_dev_s *dev, enum spi_mode_e mode) { FAR struct stm32_spidev_s *priv = (FAR struct stm32_spidev_s *)dev; uint16_t setbits; uint16_t clrbits; spiinfo("mode=%d\n", mode); /* Has the mode changed? */ if (mode != priv->mode) { /* Yes... Set CR1 appropriately */ switch (mode) { case SPIDEV_MODE0: /* CPOL=0; CPHA=0 */ setbits = 0; clrbits = SPI_CR1_CPOL | SPI_CR1_CPHA; break; case SPIDEV_MODE1: /* CPOL=0; CPHA=1 */ setbits = SPI_CR1_CPHA; clrbits = SPI_CR1_CPOL; break; case SPIDEV_MODE2: /* CPOL=1; CPHA=0 */ setbits = SPI_CR1_CPOL; clrbits = SPI_CR1_CPHA; break; case SPIDEV_MODE3: /* CPOL=1; CPHA=1 */ setbits = SPI_CR1_CPOL | SPI_CR1_CPHA; clrbits = 0; break; default: return; } spi_modifycr1(priv, 0, SPI_CR1_SPE); spi_modifycr1(priv, setbits, clrbits); spi_modifycr1(priv, SPI_CR1_SPE, 0); /* Save the mode so that subsequent re-configurations will be faster */ priv->mode = mode; } } /************************************************************************************ * Name: spi_setbits * * Description: * Set the number of bits per word. * * Input Parameters: * dev - Device-specific state data * nbits - The number of bits requested * * Returned Value: * None * ************************************************************************************/ static void spi_setbits(FAR struct spi_dev_s *dev, int nbits) { FAR struct stm32_spidev_s *priv = (FAR struct stm32_spidev_s *)dev; uint16_t setbits; uint16_t clrbits; spiinfo("nbits=%d\n", nbits); /* Has the number of bits changed? */ if (nbits != priv->nbits) { /* Yes... Set CR1 appropriately */ switch (nbits) { case 8: setbits = 0; clrbits = SPI_CR1_DFF; break; case 16: setbits = SPI_CR1_DFF; clrbits = 0; break; default: return; } spi_modifycr1(priv, 0, SPI_CR1_SPE); spi_modifycr1(priv, setbits, clrbits); spi_modifycr1(priv, SPI_CR1_SPE, 0); /* Save the selection so the subsequence re-configurations will be faster */ priv->nbits = nbits; } } /**************************************************************************** * Name: spi_hwfeatures * * Description: * Set hardware-specific feature flags. * * Input Parameters: * dev - Device-specific state data * features - H/W feature flags * * Returned Value: * Zero (OK) if the selected H/W features are enabled; A negated errno * value if any H/W feature is not supportable. * ****************************************************************************/ #ifdef CONFIG_SPI_HWFEATURES static int spi_hwfeatures(FAR struct spi_dev_s *dev, spi_hwfeatures_t features) { #ifdef CONFIG_SPI_BITORDER FAR struct stm32_spidev_s *priv = (FAR struct stm32_spidev_s *)dev; uint16_t setbits; uint16_t clrbits; spiinfo("features=%08x\n", features); /* Transfer data LSB first? */ if ((features & HWFEAT_LSBFIRST) != 0) { setbits = SPI_CR1_LSBFIRST; clrbits = 0; } else { setbits = 0; clrbits = SPI_CR1_LSBFIRST; } spi_modifycr1(priv, 0, SPI_CR1_SPE); spi_modifycr1(priv, setbits, clrbits); spi_modifycr1(priv, SPI_CR1_SPE, 0); /* Other H/W features are not supported */ return ((features & ~HWFEAT_LSBFIRST) == 0) ? OK : -ENOSYS; #else return -ENOSYS; #endif } #endif /************************************************************************************ * Name: spi_send * * Description: * Exchange one word on SPI * * Input Parameters: * dev - Device-specific state data * wd - The word to send. the size of the data is determined by the * number of bits selected for the SPI interface. * * Returned Value: * response * ************************************************************************************/ static uint16_t spi_send(FAR struct spi_dev_s *dev, uint16_t wd) { FAR struct stm32_spidev_s *priv = (FAR struct stm32_spidev_s *)dev; uint32_t regval; uint16_t ret; DEBUGASSERT(priv && priv->spibase); spi_writeword(priv, wd); ret = spi_readword(priv); /* Check and clear any error flags (Reading from the SR clears the error flags) */ regval = spi_getreg(priv, STM32_SPI_SR_OFFSET); spiinfo("Sent: %04x Return: %04x Status: %02x\n", wd, ret, regval); UNUSED(regval); return ret; } /************************************************************************************ * Name: spi_exchange (no DMA). aka spi_exchange_nodma * * Description: * Exchange a block of data on SPI without using DMA * * Input Parameters: * dev - Device-specific state data * txbuffer - A pointer to the buffer of data to be sent * rxbuffer - A pointer to a buffer in which to receive data * nwords - the length of data to be exchaned in units of words. * The wordsize is determined by the number of bits-per-word * selected for the SPI interface. If nbits <= 8, the data is * packed into uint8_t's; if nbits >8, the data is packed into uint16_t's * * Returned Value: * None * ************************************************************************************/ #if !defined(CONFIG_STM32_SPI_DMA) || defined(CONFIG_STM32_DMACAPABLE) #if !defined(CONFIG_STM32_SPI_DMA) static void spi_exchange(FAR struct spi_dev_s *dev, FAR const void *txbuffer, FAR void *rxbuffer, size_t nwords) #else static void spi_exchange_nodma(FAR struct spi_dev_s *dev, FAR const void *txbuffer, FAR void *rxbuffer, size_t nwords) #endif { FAR struct stm32_spidev_s *priv = (FAR struct stm32_spidev_s *)dev; DEBUGASSERT(priv && priv->spibase); spiinfo("txbuffer=%p rxbuffer=%p nwords=%d\n", txbuffer, rxbuffer, nwords); /* 8- or 16-bit mode? */ if (spi_16bitmode(priv)) { /* 16-bit mode */ const uint16_t *src = (const uint16_t *)txbuffer; uint16_t *dest = (uint16_t *)rxbuffer; uint16_t word; while (nwords-- > 0) { /* Get the next word to write. Is there a source buffer? */ if (src) { word = *src++; } else { word = 0xffff; } /* Exchange one word */ word = spi_send(dev, word); /* Is there a buffer to receive the return value? */ if (dest) { *dest++ = word; } } } else { /* 8-bit mode */ const uint8_t *src = (const uint8_t *)txbuffer; uint8_t *dest = (uint8_t *)rxbuffer; uint8_t word; while (nwords-- > 0) { /* Get the next word to write. Is there a source buffer? */ if (src) { word = *src++; } else { word = 0xff; } /* Exchange one word */ word = (uint8_t)spi_send(dev, (uint16_t)word); /* Is there a buffer to receive the return value? */ if (dest) { *dest++ = word; } } } } #endif /* !CONFIG_STM32_SPI_DMA || CONFIG_STM32_DMACAPABLE */ /**************************************************************************** * Name: spi_exchange (with DMA capability) * * Description: * Exchange a block of data on SPI using DMA * * Input Parameters: * dev - Device-specific state data * txbuffer - A pointer to the buffer of data to be sent * rxbuffer - A pointer to a buffer in which to receive data * nwords - the length of data to be exchanged in units of words. * The wordsize is determined by the number of bits-per-word * selected for the SPI interface. If nbits <= 8, the data is * packed into uint8_t's; if nbits >8, the data is packed into uint16_t's * * Returned Value: * None * ************************************************************************************/ #ifdef CONFIG_STM32_SPI_DMA static void spi_exchange(FAR struct spi_dev_s *dev, FAR const void *txbuffer, FAR void *rxbuffer, size_t nwords) { FAR struct stm32_spidev_s *priv = (FAR struct stm32_spidev_s *)dev; #ifdef CONFIG_STM32_DMACAPABLE if ((txbuffer && !stm32_dmacapable((uint32_t)txbuffer, nwords, priv->txccr)) || (rxbuffer && !stm32_dmacapable((uint32_t)rxbuffer, nwords, priv->rxccr))) { /* Unsupported memory region, fall back to non-DMA method. */ spi_exchange_nodma(dev, txbuffer, rxbuffer, nwords); } else #endif { static uint16_t rxdummy = 0xffff; static const uint16_t txdummy = 0xffff; spiinfo("txbuffer=%p rxbuffer=%p nwords=%d\n", txbuffer, rxbuffer, nwords); DEBUGASSERT(priv && priv->spibase); /* Setup DMAs */ spi_dmarxsetup(priv, rxbuffer, &rxdummy, nwords); spi_dmatxsetup(priv, txbuffer, &txdummy, nwords); /* Start the DMAs */ spi_dmarxstart(priv); spi_dmatxstart(priv); /* Then wait for each to complete */ spi_dmarxwait(priv); spi_dmatxwait(priv); } } #endif /* CONFIG_STM32_SPI_DMA */ /**************************************************************************** * Name: spi_sndblock * * Description: * Send a block of data on SPI * * Input Parameters: * dev - Device-specific state data * txbuffer - A pointer to the buffer of data to be sent * nwords - the length of data to send from the buffer in number of words. * The wordsize is determined by the number of bits-per-word * selected for the SPI interface. If nbits <= 8, the data is * packed into uint8_t's; if nbits >8, the data is packed into uint16_t's * * Returned Value: * None * ************************************************************************************/ #ifndef CONFIG_SPI_EXCHANGE static void spi_sndblock(FAR struct spi_dev_s *dev, FAR const void *txbuffer, size_t nwords) { spiinfo("txbuffer=%p nwords=%d\n", txbuffer, nwords); return spi_exchange(dev, txbuffer, NULL, nwords); } #endif /************************************************************************************ * Name: spi_recvblock * * Description: * Receive a block of data from SPI * * Input Parameters: * dev - Device-specific state data * rxbuffer - A pointer to the buffer in which to recieve data * nwords - the length of data that can be received in the buffer in number * of words. The wordsize is determined by the number of bits-per-word * selected for the SPI interface. If nbits <= 8, the data is * packed into uint8_t's; if nbits >8, the data is packed into uint16_t's * * Returned Value: * None * ************************************************************************************/ #ifndef CONFIG_SPI_EXCHANGE static void spi_recvblock(FAR struct spi_dev_s *dev, FAR void *rxbuffer, size_t nwords) { spiinfo("rxbuffer=%p nwords=%d\n", rxbuffer, nwords); return spi_exchange(dev, NULL, rxbuffer, nwords); } #endif /************************************************************************************ * Name: spi_bus_initialize * * Description: * Initialize the selected SPI bus in its default state (Master, 8-bit, mode 0, etc.) * * Input Parameter: * priv - private SPI device structure * * Returned Value: * None * ************************************************************************************/ static void spi_bus_initialize(FAR struct stm32_spidev_s *priv) { uint16_t setbits; uint16_t clrbits; /* Configure CR1. Default configuration: * Mode 0: CPHA=0 and CPOL=0 * Master: MSTR=1 * 8-bit: DFF=0 * MSB tranmitted first: LSBFIRST=0 * Replace NSS with SSI & SSI=1: SSI=1 SSM=1 (prevents MODF error) * Two lines full duplex: BIDIMODE=0 BIDIOIE=(Don't care) and RXONLY=0 */ clrbits = SPI_CR1_CPHA | SPI_CR1_CPOL | SPI_CR1_BR_MASK | SPI_CR1_LSBFIRST | SPI_CR1_RXONLY | SPI_CR1_DFF | SPI_CR1_BIDIOE | SPI_CR1_BIDIMODE; setbits = SPI_CR1_MSTR | SPI_CR1_SSI | SPI_CR1_SSM; spi_modifycr1(priv, setbits, clrbits); priv->frequency = 0; priv->nbits = 8; priv->mode = SPIDEV_MODE0; /* Select a default frequency of approx. 400KHz */ spi_setfrequency((FAR struct spi_dev_s *)priv, 400000); /* CRCPOLY configuration */ spi_putreg(priv, STM32_SPI_CRCPR_OFFSET, 7); /* Initialize the SPI semaphore that enforces mutually exclusive access */ sem_init(&priv->exclsem, 0, 1); /* Initialize the SPI semaphores that is used to wait for DMA completion */ #ifdef CONFIG_STM32_SPI_DMA sem_init(&priv->rxsem, 0, 0); sem_init(&priv->txsem, 0, 0); /* Get DMA channels. NOTE: stm32_dmachannel() will always assign the DMA channel. * if the channel is not available, then stm32_dmachannel() will block and wait * until the channel becomes available. WARNING: If you have another device sharing * a DMA channel with SPI and the code never releases that channel, then the call * to stm32_dmachannel() will hang forever in this function! Don't let your * design do that! */ priv->rxdma = stm32_dmachannel(priv->rxch); priv->txdma = stm32_dmachannel(priv->txch); DEBUGASSERT(priv->rxdma && priv->txdma); spi_putreg(priv, STM32_SPI_CR2_OFFSET, SPI_CR2_RXDMAEN | SPI_CR2_TXDMAEN); #endif /* Enable spi */ spi_modifycr1(priv, SPI_CR1_SPE, 0); } /************************************************************************************ * Public Functions ************************************************************************************/ /************************************************************************************ * Name: stm32_spibus_initialize * * Description: * Initialize the selected SPI bus * * Input Parameter: * Port number (for hardware that has mutiple SPI interfaces) * * Returned Value: * Valid SPI device structure reference on succcess; a NULL on failure * ************************************************************************************/ FAR struct spi_dev_s *stm32_spibus_initialize(int bus) { FAR struct stm32_spidev_s *priv = NULL; irqstate_t flags = enter_critical_section(); #ifdef CONFIG_STM32_SPI1 if (bus == 1) { /* Select SPI1 */ priv = &g_spi1dev; /* Only configure if the bus is not already configured */ if ((spi_getreg(priv, STM32_SPI_CR1_OFFSET) & SPI_CR1_SPE) == 0) { /* Configure SPI1 pins: SCK, MISO, and MOSI */ stm32_configgpio(GPIO_SPI1_SCK); stm32_configgpio(GPIO_SPI1_MISO); stm32_configgpio(GPIO_SPI1_MOSI); /* Set up default configuration: Master, 8-bit, etc. */ spi_bus_initialize(priv); } } else #endif #ifdef CONFIG_STM32_SPI2 if (bus == 2) { /* Select SPI2 */ priv = &g_spi2dev; /* Only configure if the bus is not already configured */ if ((spi_getreg(priv, STM32_SPI_CR1_OFFSET) & SPI_CR1_SPE) == 0) { /* Configure SPI2 pins: SCK, MISO, and MOSI */ stm32_configgpio(GPIO_SPI2_SCK); stm32_configgpio(GPIO_SPI2_MISO); stm32_configgpio(GPIO_SPI2_MOSI); /* Set up default configuration: Master, 8-bit, etc. */ spi_bus_initialize(priv); } } else #endif #ifdef CONFIG_STM32_SPI3 if (bus == 3) { /* Select SPI3 */ priv = &g_spi3dev; /* Only configure if the bus is not already configured */ if ((spi_getreg(priv, STM32_SPI_CR1_OFFSET) & SPI_CR1_SPE) == 0) { /* Configure SPI3 pins: SCK, MISO, and MOSI */ stm32_configgpio(GPIO_SPI3_SCK); stm32_configgpio(GPIO_SPI3_MISO); stm32_configgpio(GPIO_SPI3_MOSI); /* Set up default configuration: Master, 8-bit, etc. */ spi_bus_initialize(priv); } } else #endif #ifdef CONFIG_STM32_SPI4 if (bus == 4) { /* Select SPI4 */ priv = &g_spi4dev; /* Only configure if the bus is not already configured */ if ((spi_getreg(priv, STM32_SPI_CR1_OFFSET) & SPI_CR1_SPE) == 0) { /* Configure SPI4 pins: SCK, MISO, and MOSI */ stm32_configgpio(GPIO_SPI4_SCK); stm32_configgpio(GPIO_SPI4_MISO); stm32_configgpio(GPIO_SPI4_MOSI); /* Set up default configuration: Master, 8-bit, etc. */ spi_bus_initialize(priv); } } else #endif #ifdef CONFIG_STM32_SPI5 if (bus == 5) { /* Select SPI5 */ priv = &g_spi5dev; /* Only configure if the bus is not already configured */ if ((spi_getreg(priv, STM32_SPI_CR1_OFFSET) & SPI_CR1_SPE) == 0) { /* Configure SPI5 pins: SCK, MISO, and MOSI */ stm32_configgpio(GPIO_SPI5_SCK); stm32_configgpio(GPIO_SPI5_MISO); stm32_configgpio(GPIO_SPI5_MOSI); /* Set up default configuration: Master, 8-bit, etc. */ spi_bus_initialize(priv); } } else #endif #ifdef CONFIG_STM32_SPI6 if (bus == 6) { /* Select SPI6 */ priv = &g_spi6dev; /* Only configure if the bus is not already configured */ if ((spi_getreg(priv, STM32_SPI_CR1_OFFSET) & SPI_CR1_SPE) == 0) { /* Configure SPI6 pins: SCK, MISO, and MOSI */ stm32_configgpio(GPIO_SPI6_SCK); stm32_configgpio(GPIO_SPI6_MISO); stm32_configgpio(GPIO_SPI6_MOSI); /* Set up default configuration: Master, 8-bit, etc. */ spi_bus_initialize(priv); } } else #endif { spierr("ERROR: Unsupbused SPI bus: %d\n", bus); return NULL; } leave_critical_section(flags); return (FAR struct spi_dev_s *)priv; } #endif /* CONFIG_STM32_SPI1 || CONFIG_STM32_SPI2 || CONFIG_STM32_SPI3 || CONFIG_STM32_SPI4 || CONFIG_STM32_SPI5 || CONFIG_STM32_SPI6 */