mbed library sources. Supersedes mbed-src.
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Diff: targets/hal/TARGET_STM/TARGET_STM32F7/spi_api.c
- Revision:
- 0:9b334a45a8ff
- Child:
- 74:9322579e4309
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/targets/hal/TARGET_STM/TARGET_STM32F7/spi_api.c Thu Oct 01 15:25:22 2015 +0300 @@ -0,0 +1,320 @@ +/* mbed Microcontroller Library + ******************************************************************************* + * Copyright (c) 2015, STMicroelectronics + * All rights reserved. + * + * 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 of STMicroelectronics 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 HOLDER 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. + ******************************************************************************* + */ +#include "mbed_assert.h" +#include "spi_api.h" + +#if DEVICE_SPI + +#include <math.h> +#include "cmsis.h" +#include "pinmap.h" +#include "PeripheralPins.h" +#include "mbed_error.h" + +static SPI_HandleTypeDef SpiHandle; + +static void init_spi(spi_t *obj) +{ + SpiHandle.Instance = (SPI_TypeDef *)(obj->spi); + + __HAL_SPI_DISABLE(&SpiHandle); + + SpiHandle.Init.Mode = obj->mode; + SpiHandle.Init.BaudRatePrescaler = obj->br_presc; + SpiHandle.Init.Direction = SPI_DIRECTION_2LINES; + SpiHandle.Init.CLKPhase = obj->cpha; + SpiHandle.Init.CLKPolarity = obj->cpol; + SpiHandle.Init.CRCCalculation = SPI_CRCCALCULATION_DISABLED; + SpiHandle.Init.CRCPolynomial = 7; + SpiHandle.Init.DataSize = obj->bits; + SpiHandle.Init.FirstBit = SPI_FIRSTBIT_MSB; + SpiHandle.Init.NSS = obj->nss; + SpiHandle.Init.TIMode = SPI_TIMODE_DISABLED; + + if (HAL_SPI_Init(&SpiHandle) != HAL_OK) { + error("Cannot initialize SPI"); + } + + __HAL_SPI_ENABLE(&SpiHandle); +} + +void spi_init(spi_t *obj, PinName mosi, PinName miso, PinName sclk, PinName ssel) +{ + // Determine the SPI to use + SPIName spi_mosi = (SPIName)pinmap_peripheral(mosi, PinMap_SPI_MOSI); + SPIName spi_miso = (SPIName)pinmap_peripheral(miso, PinMap_SPI_MISO); + SPIName spi_sclk = (SPIName)pinmap_peripheral(sclk, PinMap_SPI_SCLK); + SPIName spi_ssel = (SPIName)pinmap_peripheral(ssel, PinMap_SPI_SSEL); + + SPIName spi_data = (SPIName)pinmap_merge(spi_mosi, spi_miso); + SPIName spi_cntl = (SPIName)pinmap_merge(spi_sclk, spi_ssel); + + obj->spi = (SPIName)pinmap_merge(spi_data, spi_cntl); + MBED_ASSERT(obj->spi != (SPIName)NC); + + // Enable SPI clock + if (obj->spi == SPI_2) { + __HAL_RCC_SPI2_CLK_ENABLE(); + } + + if (obj->spi == SPI_5) { + __HAL_RCC_SPI5_CLK_ENABLE(); + } + + // Configure the SPI pins + pinmap_pinout(mosi, PinMap_SPI_MOSI); + pinmap_pinout(miso, PinMap_SPI_MISO); + pinmap_pinout(sclk, PinMap_SPI_SCLK); + + // Save new values + obj->bits = SPI_DATASIZE_8BIT; + obj->cpol = SPI_POLARITY_LOW; + obj->cpha = SPI_PHASE_1EDGE; + obj->br_presc = SPI_BAUDRATEPRESCALER_256; + + obj->pin_miso = miso; + obj->pin_mosi = mosi; + obj->pin_sclk = sclk; + obj->pin_ssel = ssel; + + if (ssel != NC) { + pinmap_pinout(ssel, PinMap_SPI_SSEL); + } else { + obj->nss = SPI_NSS_SOFT; + } + + init_spi(obj); +} + +void spi_free(spi_t *obj) +{ + // Reset SPI and disable clock + if (obj->spi == SPI_2) { + __HAL_RCC_SPI2_FORCE_RESET(); + __HAL_RCC_SPI2_RELEASE_RESET(); + __HAL_RCC_SPI2_CLK_DISABLE(); + } + + if (obj->spi == SPI_5) { + __HAL_RCC_SPI5_FORCE_RESET(); + __HAL_RCC_SPI5_RELEASE_RESET(); + __HAL_RCC_SPI5_CLK_DISABLE(); + } + + // Configure GPIOs + pin_function(obj->pin_miso, STM_PIN_DATA(STM_MODE_INPUT, GPIO_NOPULL, 0)); + pin_function(obj->pin_mosi, STM_PIN_DATA(STM_MODE_INPUT, GPIO_NOPULL, 0)); + pin_function(obj->pin_sclk, STM_PIN_DATA(STM_MODE_INPUT, GPIO_NOPULL, 0)); + pin_function(obj->pin_ssel, STM_PIN_DATA(STM_MODE_INPUT, GPIO_NOPULL, 0)); +} + +void spi_format(spi_t *obj, int bits, int mode, int slave) +{ + // Save new values + if (bits == 16) { + obj->bits = SPI_DATASIZE_16BIT; + } else { + obj->bits = SPI_DATASIZE_8BIT; + } + + switch (mode) { + case 0: + obj->cpol = SPI_POLARITY_LOW; + obj->cpha = SPI_PHASE_1EDGE; + break; + case 1: + obj->cpol = SPI_POLARITY_LOW; + obj->cpha = SPI_PHASE_2EDGE; + break; + case 2: + obj->cpol = SPI_POLARITY_HIGH; + obj->cpha = SPI_PHASE_1EDGE; + break; + default: + obj->cpol = SPI_POLARITY_HIGH; + obj->cpha = SPI_PHASE_2EDGE; + break; + } + + if (obj->nss != SPI_NSS_SOFT) { + obj->nss = (slave) ? SPI_NSS_HARD_INPUT : SPI_NSS_HARD_OUTPUT; + } + + obj->mode = (slave) ? SPI_MODE_SLAVE : SPI_MODE_MASTER; + + init_spi(obj); +} + +void spi_frequency(spi_t *obj, int hz) +{ + // The frequencies are obtained with: + // - SPI2 clock = 54 MHz (APB1 clock) + // - SPI5 clock = 108 MHz (APB2 clock) + if (obj->spi == SPI_2) { + if (hz < 400000) { + obj->br_presc = SPI_BAUDRATEPRESCALER_256; // 211 kHz + } else if ((hz >= 400000) && (hz < 800000)) { + obj->br_presc = SPI_BAUDRATEPRESCALER_128; // 422 kHz + } else if ((hz >= 800000) && (hz < 1000000)) { + obj->br_presc = SPI_BAUDRATEPRESCALER_64; // 844 kHz + } else if ((hz >= 1000000) && (hz < 3000000)) { + obj->br_presc = SPI_BAUDRATEPRESCALER_32; // 1.69 MHz + } else if ((hz >= 3000000) && (hz < 6000000)) { + obj->br_presc = SPI_BAUDRATEPRESCALER_16; // 3.38 MHz + } else if ((hz >= 6000000) && (hz < 12000000)) { + obj->br_presc = SPI_BAUDRATEPRESCALER_8; // 6.75 MHz + } else if ((hz >= 12000000) && (hz < 24000000)) { + obj->br_presc = SPI_BAUDRATEPRESCALER_4; // 13.5 MHz + } else { // >= 24000000 + obj->br_presc = SPI_BAUDRATEPRESCALER_2; // 27 MHz + } + } else if (obj->spi == SPI_5) { + if (hz < 800000) { + obj->br_presc = SPI_BAUDRATEPRESCALER_256; // 422 kHz + } else if ((hz >= 800000) && (hz < 1000000)) { + obj->br_presc = SPI_BAUDRATEPRESCALER_128; // 844 kHz + } else if ((hz >= 1000000) && (hz < 3000000)) { + obj->br_presc = SPI_BAUDRATEPRESCALER_64; // 1.69 MHz + } else if ((hz >= 3000000) && (hz < 6000000)) { + obj->br_presc = SPI_BAUDRATEPRESCALER_32; // 3.38 MHz + } else if ((hz >= 6000000) && (hz < 12000000)) { + obj->br_presc = SPI_BAUDRATEPRESCALER_16; // 6.75 MHz + } else if ((hz >= 12000000) && (hz < 24000000)) { + obj->br_presc = SPI_BAUDRATEPRESCALER_8; // 13.5 MHz + } else if ((hz >= 24000000) && (hz < 54000000)) { + obj->br_presc = SPI_BAUDRATEPRESCALER_4; // 27 MHz + } else { // >= 54000000 + obj->br_presc = SPI_BAUDRATEPRESCALER_2; // 54 MHz + } + } else { + return; + } + init_spi(obj); +} + +static inline int ssp_readable(spi_t *obj) +{ + int status; + SpiHandle.Instance = (SPI_TypeDef *)(obj->spi); + // Check if data is received + status = ((__HAL_SPI_GET_FLAG(&SpiHandle, SPI_FLAG_RXNE) != RESET) ? 1 : 0); + return status; +} + +static inline int ssp_writeable(spi_t *obj) +{ + int status; + SpiHandle.Instance = (SPI_TypeDef *)(obj->spi); + // Check if data is transmitted + status = ((__HAL_SPI_GET_FLAG(&SpiHandle, SPI_FLAG_TXE) != RESET) ? 1 : 0); + return status; +} + +static inline void ssp_write(spi_t *obj, int value) +{ + SPI_TypeDef *spi = (SPI_TypeDef *)(obj->spi); + while (!ssp_writeable(obj)); + if (obj->bits == SPI_DATASIZE_8BIT) { + // Force 8-bit access to the data register + uint8_t *p_spi_dr = 0; + p_spi_dr = (uint8_t *) & (spi->DR); + *p_spi_dr = (uint8_t)value; + } else { // SPI_DATASIZE_16BIT + spi->DR = (uint16_t)value; + } +} + +static inline int ssp_read(spi_t *obj) +{ + SPI_TypeDef *spi = (SPI_TypeDef *)(obj->spi); + while (!ssp_readable(obj)); + if (obj->bits == SPI_DATASIZE_8BIT) { + // Force 8-bit access to the data register + uint8_t *p_spi_dr = 0; + p_spi_dr = (uint8_t *) & (spi->DR); + return (int)(*p_spi_dr); + } else { + return (int)spi->DR; + } +} + +static inline int ssp_busy(spi_t *obj) +{ + int status; + SpiHandle.Instance = (SPI_TypeDef *)(obj->spi); + status = ((__HAL_SPI_GET_FLAG(&SpiHandle, SPI_FLAG_BSY) != RESET) ? 1 : 0); + return status; +} + +int spi_master_write(spi_t *obj, int value) +{ + ssp_write(obj, value); + return ssp_read(obj); +} + +int spi_slave_receive(spi_t *obj) +{ + return ((ssp_readable(obj) && !ssp_busy(obj)) ? 1 : 0); +}; + +int spi_slave_read(spi_t *obj) +{ + SPI_TypeDef *spi = (SPI_TypeDef *)(obj->spi); + while (!ssp_readable(obj)); + if (obj->bits == SPI_DATASIZE_8BIT) { + // Force 8-bit access to the data register + uint8_t *p_spi_dr = 0; + p_spi_dr = (uint8_t *) & (spi->DR); + return (int)(*p_spi_dr); + } else { + return (int)spi->DR; + } +} + +void spi_slave_write(spi_t *obj, int value) +{ + SPI_TypeDef *spi = (SPI_TypeDef *)(obj->spi); + while (!ssp_writeable(obj)); + if (obj->bits == SPI_DATASIZE_8BIT) { + // Force 8-bit access to the data register + uint8_t *p_spi_dr = 0; + p_spi_dr = (uint8_t *) & (spi->DR); + *p_spi_dr = (uint8_t)value; + } else { // SPI_DATASIZE_16BIT + spi->DR = (uint16_t)value; + } +} + +int spi_busy(spi_t *obj) +{ + return ssp_busy(obj); +} + +#endif