tool/mbed/mbed-sdk/libraries/mbed/targets/hal/TARGET_STM/TARGET_STM32F1/spi_api.c

   1 /* mbed Microcontroller Library
   2  *******************************************************************************
   3  * Copyright (c) 2014, STMicroelectronics
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions are met:
   8  *
   9  * 1. Redistributions of source code must retain the above copyright notice,
  10  *    this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright notice,
  12  *    this list of conditions and the following disclaimer in the documentation
  13  *    and/or other materials provided with the distribution.
  14  * 3. Neither the name of STMicroelectronics nor the names of its contributors
  15  *    may be used to endorse or promote products derived from this software
  16  *    without specific prior written permission.
  17  *
  18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  19  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  21  * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
  22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  24  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  25  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  26  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  27  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  28  *******************************************************************************
  29  */
  30 #include "mbed_assert.h"
  31 #include "spi_api.h"
  32
  33 #if DEVICE_SPI
  34
  35 #include <math.h>
  36 #include "cmsis.h"
  37 #include "pinmap.h"
  38 #include "PeripheralPins.h"
  39
  40 static SPI_HandleTypeDef SpiHandle;
  41
  42 static void init_spi(spi_t *obj)
  43 {
  44     SpiHandle.Instance = (SPI_TypeDef *)(obj->spi);
  45
  46     __HAL_SPI_DISABLE(&SpiHandle);
  47
  48     SpiHandle.Init.Mode              = obj->mode;
  49     SpiHandle.Init.BaudRatePrescaler = obj->br_presc;
  50     SpiHandle.Init.Direction         = SPI_DIRECTION_2LINES;
  51     SpiHandle.Init.CLKPhase          = obj->cpha;
  52     SpiHandle.Init.CLKPolarity       = obj->cpol;
  53     SpiHandle.Init.CRCCalculation    = SPI_CRCCALCULATION_DISABLED;
  54     SpiHandle.Init.CRCPolynomial     = 7;
  55     SpiHandle.Init.DataSize          = obj->bits;
  56     SpiHandle.Init.FirstBit          = SPI_FIRSTBIT_MSB;
  57     SpiHandle.Init.NSS               = obj->nss;
  58     SpiHandle.Init.TIMode            = SPI_TIMODE_DISABLED;
  59
  60     HAL_SPI_Init(&SpiHandle);
  61
  62     __HAL_SPI_ENABLE(&SpiHandle);
  63 }
  64
  65 void spi_init(spi_t *obj, PinName mosi, PinName miso, PinName sclk, PinName ssel)
  66 {
  67     // Determine the SPI to use
  68     SPIName spi_mosi = (SPIName)pinmap_peripheral(mosi, PinMap_SPI_MOSI);
  69     SPIName spi_miso = (SPIName)pinmap_peripheral(miso, PinMap_SPI_MISO);
  70     SPIName spi_sclk = (SPIName)pinmap_peripheral(sclk, PinMap_SPI_SCLK);
  71     SPIName spi_ssel = (SPIName)pinmap_peripheral(ssel, PinMap_SPI_SSEL);
  72
  73     SPIName spi_data = (SPIName)pinmap_merge(spi_mosi, spi_miso);
  74     SPIName spi_cntl = (SPIName)pinmap_merge(spi_sclk, spi_ssel);
  75
  76     obj->spi = (SPIName)pinmap_merge(spi_data, spi_cntl);
  77     MBED_ASSERT(obj->spi != (SPIName)NC);
  78
  79     // Enable SPI clock
  80     if (obj->spi == SPI_1) {
  81         __SPI1_CLK_ENABLE();
  82     }
  83     if (obj->spi == SPI_2) {
  84         __SPI2_CLK_ENABLE();
  85     }
  86
  87     // Configure the SPI pins
  88     pinmap_pinout(mosi, PinMap_SPI_MOSI);
  89     pinmap_pinout(miso, PinMap_SPI_MISO);
  90     pinmap_pinout(sclk, PinMap_SPI_SCLK);
  91
  92     // Save new values
  93     obj->bits = SPI_DATASIZE_8BIT;
  94     obj->cpol = SPI_POLARITY_LOW;
  95     obj->cpha = SPI_PHASE_1EDGE;
  96     obj->br_presc = SPI_BAUDRATEPRESCALER_256;
  97
  98     obj->pin_miso = miso;
  99     obj->pin_mosi = mosi;
 100     obj->pin_sclk = sclk;
 101     obj->pin_ssel = ssel;
 102
 103     if (ssel == NC) { // SW NSS Master mode
 104         obj->mode = SPI_MODE_MASTER;
 105         obj->nss = SPI_NSS_SOFT;
 106     } else { // Slave
 107         pinmap_pinout(ssel, PinMap_SPI_SSEL);
 108         obj->mode = SPI_MODE_SLAVE;
 109         obj->nss = SPI_NSS_HARD_INPUT;
 110     }
 111
 112     init_spi(obj);
 113 }
 114
 115 void spi_free(spi_t *obj)
 116 {
 117     // Reset SPI and disable clock
 118     if (obj->spi == SPI_1) {
 119         __SPI1_FORCE_RESET();
 120         __SPI1_RELEASE_RESET();
 121         __SPI1_CLK_DISABLE();
 122     }
 123
 124     if (obj->spi == SPI_2) {
 125         __SPI2_FORCE_RESET();
 126         __SPI2_RELEASE_RESET();
 127         __SPI2_CLK_DISABLE();
 128     }
 129
 130     // Configure GPIOs
 131     pin_function(obj->pin_miso, STM_PIN_DATA(STM_MODE_INPUT, GPIO_NOPULL, 0));
 132     pin_function(obj->pin_mosi, STM_PIN_DATA(STM_MODE_INPUT, GPIO_NOPULL, 0));
 133     pin_function(obj->pin_sclk, STM_PIN_DATA(STM_MODE_INPUT, GPIO_NOPULL, 0));
 134     pin_function(obj->pin_ssel, STM_PIN_DATA(STM_MODE_INPUT, GPIO_NOPULL, 0));
 135 }
 136
 137 void spi_format(spi_t *obj, int bits, int mode, int slave)
 138 {
 139     // Save new values
 140     if (bits == 16) {
 141         obj->bits = SPI_DATASIZE_16BIT;
 142     } else {
 143         obj->bits = SPI_DATASIZE_8BIT;
 144     }
 145
 146     switch (mode) {
 147         case 0:
 148             obj->cpol = SPI_POLARITY_LOW;
 149             obj->cpha = SPI_PHASE_1EDGE;
 150             break;
 151         case 1:
 152             obj->cpol = SPI_POLARITY_LOW;
 153             obj->cpha = SPI_PHASE_2EDGE;
 154             break;
 155         case 2:
 156             obj->cpol = SPI_POLARITY_HIGH;
 157             obj->cpha = SPI_PHASE_1EDGE;
 158             break;
 159         default:
 160             obj->cpol = SPI_POLARITY_HIGH;
 161             obj->cpha = SPI_PHASE_2EDGE;
 162             break;
 163     }
 164
 165     if (slave == 0) {
 166         obj->mode = SPI_MODE_MASTER;
 167         obj->nss = SPI_NSS_SOFT;
 168     } else {
 169         obj->mode = SPI_MODE_SLAVE;
 170         obj->nss = SPI_NSS_HARD_INPUT;
 171     }
 172
 173     init_spi(obj);
 174 }
 175
 176 void spi_frequency(spi_t *obj, int hz)
 177 {
 178     if (obj->spi == SPI_1) {
 179         // Values depend of PCLK2: 64 MHz if HSI is used, 72 MHz if HSE is used
 180         if (hz < 500000) {
 181             obj->br_presc = SPI_BAUDRATEPRESCALER_256; // 250 kHz - 281 kHz
 182         } else if ((hz >= 500000) && (hz < 1000000)) {
 183             obj->br_presc = SPI_BAUDRATEPRESCALER_128; // 500 kHz - 563 kHz
 184         } else if ((hz >= 1000000) && (hz < 2000000)) {
 185             obj->br_presc = SPI_BAUDRATEPRESCALER_64; // 1 MHz - 1.13 MHz
 186         } else if ((hz >= 2000000) && (hz < 4000000)) {
 187             obj->br_presc = SPI_BAUDRATEPRESCALER_32; // 2 MHz - 2.25 MHz
 188         } else if ((hz >= 4000000) && (hz < 8000000)) {
 189             obj->br_presc = SPI_BAUDRATEPRESCALER_16; // 4 MHz - 4.5 MHz
 190         } else if ((hz >= 8000000) && (hz < 16000000)) {
 191             obj->br_presc = SPI_BAUDRATEPRESCALER_8; // 8 MHz - 9 MHz
 192         } else if ((hz >= 16000000) && (hz < 32000000)) {
 193             obj->br_presc = SPI_BAUDRATEPRESCALER_4; // 16 MHz - 18 MHz
 194         } else { // >= 32000000
 195             obj->br_presc = SPI_BAUDRATEPRESCALER_2; // 32 MHz - 36 MHz
 196         }
 197     }
 198
 199     if (obj->spi == SPI_2) {
 200         // Values depend of PCLK1: 32 MHz if HSI is used, 36 MHz if HSE is used
 201         if (hz < 250000) {
 202             obj->br_presc = SPI_BAUDRATEPRESCALER_256; // 125 kHz - 141 kHz
 203         } else if ((hz >= 250000) && (hz < 500000)) {
 204             obj->br_presc = SPI_BAUDRATEPRESCALER_128; // 250 kHz - 281 kHz
 205         } else if ((hz >= 500000) && (hz < 1000000)) {
 206             obj->br_presc = SPI_BAUDRATEPRESCALER_64; // 500 kHz - 563 kHz
 207         } else if ((hz >= 1000000) && (hz < 2000000)) {
 208             obj->br_presc = SPI_BAUDRATEPRESCALER_32; // 1 MHz - 1.13 MHz
 209         } else if ((hz >= 2000000) && (hz < 4000000)) {
 210             obj->br_presc = SPI_BAUDRATEPRESCALER_16; // 2 MHz - 2.25 MHz
 211         } else if ((hz >= 4000000) && (hz < 8000000)) {
 212             obj->br_presc = SPI_BAUDRATEPRESCALER_8; // 4 MHz - 4.5 MHz
 213         } else if ((hz >= 8000000) && (hz < 16000000)) {
 214             obj->br_presc = SPI_BAUDRATEPRESCALER_4; // 8 MHz - 9 MHz
 215         } else { // >= 16000000
 216             obj->br_presc = SPI_BAUDRATEPRESCALER_2; // 16 MHz - 18 MHz
 217         }
 218     }
 219
 220     init_spi(obj);
 221 }
 222
 223 static inline int ssp_readable(spi_t *obj)
 224 {
 225     int status;
 226     SpiHandle.Instance = (SPI_TypeDef *)(obj->spi);
 227     // Check if data is received
 228     status = ((__HAL_SPI_GET_FLAG(&SpiHandle, SPI_FLAG_RXNE) != RESET) ? 1 : 0);
 229     return status;
 230 }
 231
 232 static inline int ssp_writeable(spi_t *obj)
 233 {
 234     int status;
 235     SpiHandle.Instance = (SPI_TypeDef *)(obj->spi);
 236     // Check if data is transmitted
 237     status = ((__HAL_SPI_GET_FLAG(&SpiHandle, SPI_FLAG_TXE) != RESET) ? 1 : 0);
 238     return status;
 239 }
 240
 241 static inline void ssp_write(spi_t *obj, int value)
 242 {
 243     SPI_TypeDef *spi = (SPI_TypeDef *)(obj->spi);
 244     while (!ssp_writeable(obj));
 245     if (obj->bits == SPI_DATASIZE_8BIT) {
 246         // Force 8-bit access to the data register
 247         uint8_t *p_spi_dr = 0;
 248         p_spi_dr = (uint8_t *) & (spi->DR);
 249         *p_spi_dr = (uint8_t)value;
 250     } else { // SPI_DATASIZE_16BIT
 251         spi->DR = (uint16_t)value;
 252     }
 253 }
 254
 255 static inline int ssp_read(spi_t *obj)
 256 {
 257     SPI_TypeDef *spi = (SPI_TypeDef *)(obj->spi);
 258     while (!ssp_readable(obj));
 259     if (obj->bits == SPI_DATASIZE_8BIT) {
 260         // Force 8-bit access to the data register
 261         uint8_t *p_spi_dr = 0;
 262         p_spi_dr = (uint8_t *) & (spi->DR);
 263         return (int)(*p_spi_dr);
 264     } else {
 265         return (int)spi->DR;
 266     }
 267 }
 268
 269 static inline int ssp_busy(spi_t *obj)
 270 {
 271     int status;
 272     SpiHandle.Instance = (SPI_TypeDef *)(obj->spi);
 273     status = ((__HAL_SPI_GET_FLAG(&SpiHandle, SPI_FLAG_BSY) != RESET) ? 1 : 0);
 274     return status;
 275 }
 276
 277 int spi_master_write(spi_t *obj, int value)
 278 {
 279     ssp_write(obj, value);
 280     return ssp_read(obj);
 281 }
 282
 283 int spi_slave_receive(spi_t *obj)
 284 {
 285     return ((ssp_readable(obj) && !ssp_busy(obj)) ? 1 : 0);
 286 };
 287
 288 int spi_slave_read(spi_t *obj)
 289 {
 290     SPI_TypeDef *spi = (SPI_TypeDef *)(obj->spi);
 291     while (!ssp_readable(obj));
 292     if (obj->bits == SPI_DATASIZE_8BIT) {
 293         // Force 8-bit access to the data register
 294         uint8_t *p_spi_dr = 0;
 295         p_spi_dr = (uint8_t *) & (spi->DR);
 296         return (int)(*p_spi_dr);
 297     } else {
 298         return (int)spi->DR;
 299     }
 300 }
 301
 302 void spi_slave_write(spi_t *obj, int value)
 303 {
 304     SPI_TypeDef *spi = (SPI_TypeDef *)(obj->spi);
 305     while (!ssp_writeable(obj));
 306     if (obj->bits == SPI_DATASIZE_8BIT) {
 307         // Force 8-bit access to the data register
 308         uint8_t *p_spi_dr = 0;
 309         p_spi_dr = (uint8_t *) & (spi->DR);
 310         *p_spi_dr = (uint8_t)value;
 311     } else { // SPI_DATASIZE_16BIT
 312         spi->DR = (uint16_t)value;
 313     }
 314 }
 315
 316 int spi_busy(spi_t *obj)
 317 {
 318     return ssp_busy(obj);
 319 }
 320
 321 #endif