shao ziyang / mbed-src-kl05

mbed library sources

Dependents:   frdm_kl05z_gpio_test

Fork of mbed-src by mbed official

targets/hal/TARGET_STM/TARGET_DISCO_F100RB/spi_api.c@227:7bd0639b8911, 2014-06-11 (annotated)

Committer:
mbed_official
Date:
Wed Jun 11 16:00:09 2014 +0100
Revision:
227:7bd0639b8911
Parent:
126:549ba18ddd81 
Synchronized with git revision d58d532ebc0e0a96f4fffb8edefc082b71b964af



Full URL: https://github.com/mbedmicro/mbed/commit/d58d532ebc0e0a96f4fffb8edefc082b71b964af/

Who changed what in which revision?

UserRevisionLine numberNew contents of line
mbed_official 126:549ba18ddd81 1 /* mbed Microcontroller Library
mbed_official 126:549ba18ddd81 2 *******************************************************************************
mbed_official 126:549ba18ddd81 3 * Copyright (c) 2014, STMicroelectronics
mbed_official 126:549ba18ddd81 4 * All rights reserved.
mbed_official 126:549ba18ddd81 5 *
mbed_official 126:549ba18ddd81 6 * Redistribution and use in source and binary forms, with or without
mbed_official 126:549ba18ddd81 7 * modification, are permitted provided that the following conditions are met:
mbed_official 126:549ba18ddd81 8 *
mbed_official 126:549ba18ddd81 9 * 1. Redistributions of source code must retain the above copyright notice,
mbed_official 126:549ba18ddd81 10 * this list of conditions and the following disclaimer.
mbed_official 126:549ba18ddd81 11 * 2. Redistributions in binary form must reproduce the above copyright notice,
mbed_official 126:549ba18ddd81 12 * this list of conditions and the following disclaimer in the documentation
mbed_official 126:549ba18ddd81 13 * and/or other materials provided with the distribution.
mbed_official 126:549ba18ddd81 14 * 3. Neither the name of STMicroelectronics nor the names of its contributors
mbed_official 126:549ba18ddd81 15 * may be used to endorse or promote products derived from this software
mbed_official 126:549ba18ddd81 16 * without specific prior written permission.
mbed_official 126:549ba18ddd81 17 *
mbed_official 126:549ba18ddd81 18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
mbed_official 126:549ba18ddd81 19 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
mbed_official 126:549ba18ddd81 20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
mbed_official 126:549ba18ddd81 21 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
mbed_official 126:549ba18ddd81 22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
mbed_official 126:549ba18ddd81 23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
mbed_official 126:549ba18ddd81 24 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
mbed_official 126:549ba18ddd81 25 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
mbed_official 126:549ba18ddd81 26 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
mbed_official 126:549ba18ddd81 27 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
mbed_official 126:549ba18ddd81 28 *******************************************************************************
mbed_official 126:549ba18ddd81 29 */
mbed_official 227:7bd0639b8911 30 #include "mbed_assert.h"
mbed_official 126:549ba18ddd81 31 #include "spi_api.h"
mbed_official 126:549ba18ddd81 32
mbed_official 126:549ba18ddd81 33 #if DEVICE_SPI
mbed_official 126:549ba18ddd81 34
mbed_official 126:549ba18ddd81 35 #include <math.h>
mbed_official 126:549ba18ddd81 36 #include "cmsis.h"
mbed_official 126:549ba18ddd81 37 #include "pinmap.h"
mbed_official 126:549ba18ddd81 38
mbed_official 126:549ba18ddd81 39 static const PinMap PinMap_SPI_MOSI[] = {
mbed_official 126:549ba18ddd81 40 {PA_7, SPI_1, STM_PIN_DATA(GPIO_Mode_AF_PP, 0)},
mbed_official 126:549ba18ddd81 41 {PB_5, SPI_1, STM_PIN_DATA(GPIO_Mode_AF_PP, 1)}, // Remap
mbed_official 126:549ba18ddd81 42 {NC, NC, 0}
mbed_official 126:549ba18ddd81 43 };
mbed_official 126:549ba18ddd81 44
mbed_official 126:549ba18ddd81 45 static const PinMap PinMap_SPI_MISO[] = {
mbed_official 126:549ba18ddd81 46 {PA_6, SPI_1, STM_PIN_DATA(GPIO_Mode_AF_PP, 0)},
mbed_official 126:549ba18ddd81 47 {PB_4, SPI_1, STM_PIN_DATA(GPIO_Mode_AF_PP, 1)}, // Remap
mbed_official 126:549ba18ddd81 48 {NC, NC, 0}
mbed_official 126:549ba18ddd81 49 };
mbed_official 126:549ba18ddd81 50
mbed_official 126:549ba18ddd81 51 static const PinMap PinMap_SPI_SCLK[] = {
mbed_official 126:549ba18ddd81 52 {PA_5, SPI_1, STM_PIN_DATA(GPIO_Mode_AF_PP, 0)},
mbed_official 126:549ba18ddd81 53 {PB_3, SPI_1, STM_PIN_DATA(GPIO_Mode_AF_PP, 1)}, // Remap
mbed_official 126:549ba18ddd81 54 {NC, NC, 0}
mbed_official 126:549ba18ddd81 55 };
mbed_official 126:549ba18ddd81 56
mbed_official 126:549ba18ddd81 57 // Only used in Slave mode
mbed_official 126:549ba18ddd81 58 static const PinMap PinMap_SPI_SSEL[] = {
mbed_official 126:549ba18ddd81 59 {PB_6, SPI_1, STM_PIN_DATA(GPIO_Mode_IN_FLOATING, 0)}, // Generic IO, not real H/W NSS pin
mbed_official 126:549ba18ddd81 60 {NC, NC, 0}
mbed_official 126:549ba18ddd81 61 };
mbed_official 126:549ba18ddd81 62
mbed_official 126:549ba18ddd81 63 static void init_spi(spi_t *obj) {
mbed_official 126:549ba18ddd81 64 SPI_TypeDef *spi = (SPI_TypeDef *)(obj->spi);
mbed_official 126:549ba18ddd81 65 SPI_InitTypeDef SPI_InitStructure;
mbed_official 126:549ba18ddd81 66
mbed_official 126:549ba18ddd81 67 SPI_Cmd(spi, DISABLE);
mbed_official 126:549ba18ddd81 68
mbed_official 126:549ba18ddd81 69 SPI_InitStructure.SPI_Mode = obj->mode;
mbed_official 227:7bd0639b8911 70 SPI_InitStructure.SPI_NSS = obj->nss;
mbed_official 227:7bd0639b8911 71 SPI_InitStructure.SPI_Direction = SPI_Direction_2Lines_FullDuplex;
mbed_official 126:549ba18ddd81 72 SPI_InitStructure.SPI_DataSize = obj->bits;
mbed_official 126:549ba18ddd81 73 SPI_InitStructure.SPI_CPOL = obj->cpol;
mbed_official 227:7bd0639b8911 74 SPI_InitStructure.SPI_CPHA = obj->cpha;
mbed_official 126:549ba18ddd81 75 SPI_InitStructure.SPI_BaudRatePrescaler = obj->br_presc;
mbed_official 126:549ba18ddd81 76 SPI_InitStructure.SPI_FirstBit = SPI_FirstBit_MSB;
mbed_official 126:549ba18ddd81 77 SPI_InitStructure.SPI_CRCPolynomial = 7;
mbed_official 126:549ba18ddd81 78 SPI_Init(spi, &SPI_InitStructure);
mbed_official 126:549ba18ddd81 79
mbed_official 126:549ba18ddd81 80 SPI_Cmd(spi, ENABLE);
mbed_official 126:549ba18ddd81 81 }
mbed_official 126:549ba18ddd81 82
mbed_official 126:549ba18ddd81 83 void spi_init(spi_t *obj, PinName mosi, PinName miso, PinName sclk, PinName ssel) {
mbed_official 126:549ba18ddd81 84 // Determine the SPI to use
mbed_official 126:549ba18ddd81 85 SPIName spi_mosi = (SPIName)pinmap_peripheral(mosi, PinMap_SPI_MOSI);
mbed_official 126:549ba18ddd81 86 SPIName spi_miso = (SPIName)pinmap_peripheral(miso, PinMap_SPI_MISO);
mbed_official 126:549ba18ddd81 87 SPIName spi_sclk = (SPIName)pinmap_peripheral(sclk, PinMap_SPI_SCLK);
mbed_official 126:549ba18ddd81 88 SPIName spi_ssel = (SPIName)pinmap_peripheral(ssel, PinMap_SPI_SSEL);
mbed_official 126:549ba18ddd81 89
mbed_official 126:549ba18ddd81 90 SPIName spi_data = (SPIName)pinmap_merge(spi_mosi, spi_miso);
mbed_official 126:549ba18ddd81 91 SPIName spi_cntl = (SPIName)pinmap_merge(spi_sclk, spi_ssel);
mbed_official 126:549ba18ddd81 92
mbed_official 126:549ba18ddd81 93 obj->spi = (SPIName)pinmap_merge(spi_data, spi_cntl);
mbed_official 227:7bd0639b8911 94 MBED_ASSERT(obj->spi != (SPIName)NC);
mbed_official 126:549ba18ddd81 95
mbed_official 126:549ba18ddd81 96 // Enable SPI clock
mbed_official 126:549ba18ddd81 97 if (obj->spi == SPI_1) {
mbed_official 227:7bd0639b8911 98 RCC_APB2PeriphClockCmd(RCC_APB2Periph_SPI1, ENABLE);
mbed_official 126:549ba18ddd81 99 }
mbed_official 126:549ba18ddd81 100
mbed_official 126:549ba18ddd81 101 // Configure the SPI pins
mbed_official 126:549ba18ddd81 102 pinmap_pinout(mosi, PinMap_SPI_MOSI);
mbed_official 126:549ba18ddd81 103 pinmap_pinout(miso, PinMap_SPI_MISO);
mbed_official 126:549ba18ddd81 104 pinmap_pinout(sclk, PinMap_SPI_SCLK);
mbed_official 126:549ba18ddd81 105
mbed_official 126:549ba18ddd81 106 // Save new values
mbed_official 126:549ba18ddd81 107 obj->bits = SPI_DataSize_8b;
mbed_official 126:549ba18ddd81 108 obj->cpol = SPI_CPOL_Low;
mbed_official 126:549ba18ddd81 109 obj->cpha = SPI_CPHA_1Edge;
mbed_official 126:549ba18ddd81 110 obj->br_presc = SPI_BaudRatePrescaler_256; // 1MHz
mbed_official 126:549ba18ddd81 111
mbed_official 126:549ba18ddd81 112 if (ssel == NC) { // Master
mbed_official 126:549ba18ddd81 113 obj->mode = SPI_Mode_Master;
mbed_official 126:549ba18ddd81 114 obj->nss = SPI_NSS_Soft;
mbed_official 126:549ba18ddd81 115 }
mbed_official 126:549ba18ddd81 116 else { // Slave
mbed_official 126:549ba18ddd81 117 pinmap_pinout(ssel, PinMap_SPI_SSEL);
mbed_official 126:549ba18ddd81 118 obj->mode = SPI_Mode_Slave;
mbed_official 126:549ba18ddd81 119 obj->nss = SPI_NSS_Soft;
mbed_official 126:549ba18ddd81 120 }
mbed_official 126:549ba18ddd81 121
mbed_official 126:549ba18ddd81 122 init_spi(obj);
mbed_official 126:549ba18ddd81 123 }
mbed_official 126:549ba18ddd81 124
mbed_official 126:549ba18ddd81 125 void spi_free(spi_t *obj) {
mbed_official 126:549ba18ddd81 126 SPI_TypeDef *spi = (SPI_TypeDef *)(obj->spi);
mbed_official 126:549ba18ddd81 127 SPI_I2S_DeInit(spi);
mbed_official 126:549ba18ddd81 128 }
mbed_official 126:549ba18ddd81 129
mbed_official 227:7bd0639b8911 130 void spi_format(spi_t *obj, int bits, int mode, int slave) {
mbed_official 126:549ba18ddd81 131 // Save new values
mbed_official 126:549ba18ddd81 132 if (bits == 8) {
mbed_official 126:549ba18ddd81 133 obj->bits = SPI_DataSize_8b;
mbed_official 126:549ba18ddd81 134 }
mbed_official 126:549ba18ddd81 135 else {
mbed_official 126:549ba18ddd81 136 obj->bits = SPI_DataSize_16b;
mbed_official 126:549ba18ddd81 137 }
mbed_official 126:549ba18ddd81 138
mbed_official 126:549ba18ddd81 139 switch (mode) {
mbed_official 126:549ba18ddd81 140 case 0:
mbed_official 126:549ba18ddd81 141 obj->cpol = SPI_CPOL_Low;
mbed_official 126:549ba18ddd81 142 obj->cpha = SPI_CPHA_1Edge;
mbed_official 126:549ba18ddd81 143 break;
mbed_official 126:549ba18ddd81 144 case 1:
mbed_official 126:549ba18ddd81 145 obj->cpol = SPI_CPOL_Low;
mbed_official 126:549ba18ddd81 146 obj->cpha = SPI_CPHA_2Edge;
mbed_official 126:549ba18ddd81 147 break;
mbed_official 126:549ba18ddd81 148 case 2:
mbed_official 126:549ba18ddd81 149 obj->cpol = SPI_CPOL_High;
mbed_official 227:7bd0639b8911 150 obj->cpha = SPI_CPHA_1Edge;
mbed_official 126:549ba18ddd81 151 break;
mbed_official 126:549ba18ddd81 152 default:
mbed_official 126:549ba18ddd81 153 obj->cpol = SPI_CPOL_High;
mbed_official 227:7bd0639b8911 154 obj->cpha = SPI_CPHA_2Edge;
mbed_official 126:549ba18ddd81 155 break;
mbed_official 126:549ba18ddd81 156 }
mbed_official 126:549ba18ddd81 157
mbed_official 126:549ba18ddd81 158 if (slave == 0) {
mbed_official 126:549ba18ddd81 159 obj->mode = SPI_Mode_Master;
mbed_official 126:549ba18ddd81 160 obj->nss = SPI_NSS_Soft;
mbed_official 126:549ba18ddd81 161 }
mbed_official 126:549ba18ddd81 162 else {
mbed_official 126:549ba18ddd81 163 obj->mode = SPI_Mode_Slave;
mbed_official 227:7bd0639b8911 164 obj->nss = SPI_NSS_Hard;
mbed_official 126:549ba18ddd81 165 }
mbed_official 126:549ba18ddd81 166
mbed_official 126:549ba18ddd81 167 init_spi(obj);
mbed_official 126:549ba18ddd81 168 }
mbed_official 126:549ba18ddd81 169
mbed_official 126:549ba18ddd81 170 void spi_frequency(spi_t *obj, int hz) {
mbed_official 126:549ba18ddd81 171 // Choose the baud rate divisor (between 2 and 256)
mbed_official 126:549ba18ddd81 172 uint32_t divisor = SystemCoreClock / hz;
mbed_official 126:549ba18ddd81 173
mbed_official 126:549ba18ddd81 174 // Find the nearest power-of-2
mbed_official 126:549ba18ddd81 175 divisor = (divisor > 0 ? divisor-1 : 0);
mbed_official 126:549ba18ddd81 176 divisor |= divisor >> 1;
mbed_official 126:549ba18ddd81 177 divisor |= divisor >> 2;
mbed_official 126:549ba18ddd81 178 divisor |= divisor >> 4;
mbed_official 126:549ba18ddd81 179 divisor |= divisor >> 8;
mbed_official 126:549ba18ddd81 180 divisor |= divisor >> 16;
mbed_official 126:549ba18ddd81 181 divisor++;
mbed_official 126:549ba18ddd81 182
mbed_official 126:549ba18ddd81 183 uint32_t baud_rate = __builtin_ffs(divisor) - 2;
mbed_official 126:549ba18ddd81 184
mbed_official 126:549ba18ddd81 185 // Save new value
mbed_official 126:549ba18ddd81 186 obj->br_presc = ((baud_rate > 7) ? (7 << 3) : (baud_rate << 3));
mbed_official 126:549ba18ddd81 187
mbed_official 126:549ba18ddd81 188 init_spi(obj);
mbed_official 126:549ba18ddd81 189 }
mbed_official 126:549ba18ddd81 190
mbed_official 126:549ba18ddd81 191 static inline int ssp_readable(spi_t *obj) {
mbed_official 126:549ba18ddd81 192 int status;
mbed_official 126:549ba18ddd81 193 SPI_TypeDef *spi = (SPI_TypeDef *)(obj->spi);
mbed_official 126:549ba18ddd81 194 // Check if data is received
mbed_official 126:549ba18ddd81 195 status = ((SPI_I2S_GetFlagStatus(spi, SPI_I2S_FLAG_RXNE) != RESET) ? 1 : 0);
mbed_official 227:7bd0639b8911 196 return status;
mbed_official 126:549ba18ddd81 197 }
mbed_official 126:549ba18ddd81 198
mbed_official 126:549ba18ddd81 199 static inline int ssp_writeable(spi_t *obj) {
mbed_official 126:549ba18ddd81 200 int status;
mbed_official 126:549ba18ddd81 201 SPI_TypeDef *spi = (SPI_TypeDef *)(obj->spi);
mbed_official 126:549ba18ddd81 202 // Check if data is transmitted
mbed_official 126:549ba18ddd81 203 status = ((SPI_I2S_GetFlagStatus(spi, SPI_I2S_FLAG_TXE) != RESET) ? 1 : 0);
mbed_official 126:549ba18ddd81 204 return status;
mbed_official 126:549ba18ddd81 205 }
mbed_official 126:549ba18ddd81 206
mbed_official 126:549ba18ddd81 207 static inline void ssp_write(spi_t *obj, int value) {
mbed_official 227:7bd0639b8911 208 SPI_TypeDef *spi = (SPI_TypeDef *)(obj->spi);
mbed_official 126:549ba18ddd81 209 while (!ssp_writeable(obj));
mbed_official 126:549ba18ddd81 210 SPI_I2S_SendData(spi, (uint16_t)value);
mbed_official 126:549ba18ddd81 211 }
mbed_official 126:549ba18ddd81 212
mbed_official 126:549ba18ddd81 213 static inline int ssp_read(spi_t *obj) {
mbed_official 227:7bd0639b8911 214 SPI_TypeDef *spi = (SPI_TypeDef *)(obj->spi);
mbed_official 126:549ba18ddd81 215 while (!ssp_readable(obj));
mbed_official 126:549ba18ddd81 216 return (int)SPI_I2S_ReceiveData(spi);
mbed_official 126:549ba18ddd81 217 }
mbed_official 126:549ba18ddd81 218
mbed_official 126:549ba18ddd81 219 static inline int ssp_busy(spi_t *obj) {
mbed_official 126:549ba18ddd81 220 int status;
mbed_official 126:549ba18ddd81 221 SPI_TypeDef *spi = (SPI_TypeDef *)(obj->spi);
mbed_official 126:549ba18ddd81 222 status = ((SPI_I2S_GetFlagStatus(spi, SPI_I2S_FLAG_BSY) != RESET) ? 1 : 0);
mbed_official 126:549ba18ddd81 223 return status;
mbed_official 126:549ba18ddd81 224 }
mbed_official 126:549ba18ddd81 225
mbed_official 126:549ba18ddd81 226 int spi_master_write(spi_t *obj, int value) {
mbed_official 126:549ba18ddd81 227 ssp_write(obj, value);
mbed_official 126:549ba18ddd81 228 return ssp_read(obj);
mbed_official 126:549ba18ddd81 229 }
mbed_official 126:549ba18ddd81 230
mbed_official 126:549ba18ddd81 231 int spi_slave_receive(spi_t *obj) {
mbed_official 126:549ba18ddd81 232 return (ssp_readable(obj) && !ssp_busy(obj)) ? (1) : (0);
mbed_official 126:549ba18ddd81 233 };
mbed_official 126:549ba18ddd81 234
mbed_official 126:549ba18ddd81 235 int spi_slave_read(spi_t *obj) {
mbed_official 126:549ba18ddd81 236 SPI_TypeDef *spi = (SPI_TypeDef *)(obj->spi);
mbed_official 126:549ba18ddd81 237 return (int)SPI_I2S_ReceiveData(spi);
mbed_official 126:549ba18ddd81 238 }
mbed_official 126:549ba18ddd81 239
mbed_official 126:549ba18ddd81 240 void spi_slave_write(spi_t *obj, int value) {
mbed_official 227:7bd0639b8911 241 SPI_TypeDef *spi = (SPI_TypeDef *)(obj->spi);
mbed_official 227:7bd0639b8911 242 while (!ssp_writeable(obj));
mbed_official 126:549ba18ddd81 243 SPI_I2S_SendData(spi, (uint16_t)value);
mbed_official 126:549ba18ddd81 244 }
mbed_official 126:549ba18ddd81 245
mbed_official 126:549ba18ddd81 246 int spi_busy(spi_t *obj) {
mbed_official 126:549ba18ddd81 247 return ssp_busy(obj);
mbed_official 126:549ba18ddd81 248 }
mbed_official 126:549ba18ddd81 249
mbed_official 126:549ba18ddd81 250 #endif