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Last commit 20 Feb 2019 by mbed official

targets/hal/TARGET_Freescale/TARGET_KL25Z/spi_api.c@72:248c61396e08, 2014-01-13 (annotated)

Committer:
mbed_official
Date:
Mon Jan 13 10:45:05 2014 +0000
Revision:
72:248c61396e08
Parent:
19:398f4c622e1b 
Synchronized with git revision f1904ba15c06215a7530efd2d5a16c25af9d29ff



Full URL: https://github.com/mbedmicro/mbed/commit/f1904ba15c06215a7530efd2d5a16c25af9d29ff/



KL46Z: Added Sleep, LED3 and LED4 definitions, switches

Who changed what in which revision?

UserRevisionLine numberNew contents of line
bogdanm 15:4892fe388435 1 /* mbed Microcontroller Library
bogdanm 15:4892fe388435 2 * Copyright (c) 2006-2013 ARM Limited
bogdanm 15:4892fe388435 3 *
bogdanm 15:4892fe388435 4 * Licensed under the Apache License, Version 2.0 (the "License");
bogdanm 15:4892fe388435 5 * you may not use this file except in compliance with the License.
bogdanm 15:4892fe388435 6 * You may obtain a copy of the License at
bogdanm 15:4892fe388435 7 *
bogdanm 15:4892fe388435 8 * http://www.apache.org/licenses/LICENSE-2.0
bogdanm 15:4892fe388435 9 *
bogdanm 15:4892fe388435 10 * Unless required by applicable law or agreed to in writing, software
bogdanm 15:4892fe388435 11 * distributed under the License is distributed on an "AS IS" BASIS,
bogdanm 15:4892fe388435 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
bogdanm 15:4892fe388435 13 * See the License for the specific language governing permissions and
bogdanm 15:4892fe388435 14 * limitations under the License.
bogdanm 15:4892fe388435 15 */
bogdanm 15:4892fe388435 16 #include "spi_api.h"
bogdanm 15:4892fe388435 17
bogdanm 15:4892fe388435 18 #include <math.h>
bogdanm 15:4892fe388435 19
bogdanm 15:4892fe388435 20 #include "cmsis.h"
bogdanm 15:4892fe388435 21 #include "pinmap.h"
bogdanm 15:4892fe388435 22 #include "error.h"
mbed_official 72:248c61396e08 23 #include "clk_freqs.h"
bogdanm 15:4892fe388435 24
bogdanm 15:4892fe388435 25 static const PinMap PinMap_SPI_SCLK[] = {
bogdanm 15:4892fe388435 26 {PTA15, SPI_0, 2},
bogdanm 15:4892fe388435 27 {PTB11, SPI_1, 2},
bogdanm 15:4892fe388435 28 {PTC5, SPI_0, 2},
bogdanm 15:4892fe388435 29 {PTD1, SPI_0, 2},
bogdanm 15:4892fe388435 30 {PTD5, SPI_1, 2},
bogdanm 15:4892fe388435 31 {PTE2, SPI_1, 2},
bogdanm 15:4892fe388435 32 {NC , NC , 0}
bogdanm 15:4892fe388435 33 };
bogdanm 15:4892fe388435 34
bogdanm 15:4892fe388435 35 static const PinMap PinMap_SPI_MOSI[] = {
bogdanm 15:4892fe388435 36 {PTA16, SPI_0, 2},
bogdanm 15:4892fe388435 37 {PTA17, SPI_0, 5},
bogdanm 15:4892fe388435 38 {PTB16, SPI_1, 2},
bogdanm 15:4892fe388435 39 {PTB17, SPI_1, 5},
bogdanm 15:4892fe388435 40 {PTC6, SPI_0, 2},
bogdanm 15:4892fe388435 41 {PTC7, SPI_0, 5},
bogdanm 15:4892fe388435 42 {PTD2, SPI_0, 2},
bogdanm 15:4892fe388435 43 {PTD3, SPI_0, 5},
bogdanm 15:4892fe388435 44 {PTD6, SPI_1, 2},
bogdanm 15:4892fe388435 45 {PTD7, SPI_1, 5},
bogdanm 15:4892fe388435 46 {PTE1, SPI_1, 2},
bogdanm 15:4892fe388435 47 {PTE3, SPI_1, 5},
bogdanm 15:4892fe388435 48 {NC , NC , 0}
bogdanm 15:4892fe388435 49 };
bogdanm 15:4892fe388435 50
bogdanm 15:4892fe388435 51 static const PinMap PinMap_SPI_MISO[] = {
bogdanm 15:4892fe388435 52 {PTA16, SPI_0, 5},
bogdanm 15:4892fe388435 53 {PTA17, SPI_0, 2},
bogdanm 15:4892fe388435 54 {PTB16, SPI_1, 5},
bogdanm 15:4892fe388435 55 {PTB17, SPI_1, 2},
bogdanm 15:4892fe388435 56 {PTC6, SPI_0, 5},
bogdanm 15:4892fe388435 57 {PTC7, SPI_0, 2},
bogdanm 15:4892fe388435 58 {PTD2, SPI_0, 5},
bogdanm 15:4892fe388435 59 {PTD3, SPI_0, 2},
bogdanm 15:4892fe388435 60 {PTD6, SPI_1, 5},
bogdanm 15:4892fe388435 61 {PTD7, SPI_1, 2},
bogdanm 15:4892fe388435 62 {PTE1, SPI_1, 5},
bogdanm 15:4892fe388435 63 {PTE3, SPI_1, 2},
bogdanm 15:4892fe388435 64 {NC , NC , 0}
bogdanm 15:4892fe388435 65 };
bogdanm 15:4892fe388435 66
bogdanm 15:4892fe388435 67 static const PinMap PinMap_SPI_SSEL[] = {
bogdanm 15:4892fe388435 68 {PTA14, SPI_0, 2},
bogdanm 15:4892fe388435 69 {PTB10, SPI_1, 2},
bogdanm 15:4892fe388435 70 {PTC4, SPI_0, 2},
bogdanm 15:4892fe388435 71 {PTD0, SPI_0, 2},
bogdanm 15:4892fe388435 72 {PTD4, SPI_1, 2},
bogdanm 15:4892fe388435 73 {PTE4, SPI_1, 2},
bogdanm 15:4892fe388435 74 {NC , NC , 0}
bogdanm 15:4892fe388435 75 };
bogdanm 15:4892fe388435 76
bogdanm 15:4892fe388435 77 void spi_init(spi_t *obj, PinName mosi, PinName miso, PinName sclk, PinName ssel) {
bogdanm 15:4892fe388435 78 // determine the SPI to use
bogdanm 15:4892fe388435 79 SPIName spi_mosi = (SPIName)pinmap_peripheral(mosi, PinMap_SPI_MOSI);
bogdanm 15:4892fe388435 80 SPIName spi_miso = (SPIName)pinmap_peripheral(miso, PinMap_SPI_MISO);
bogdanm 15:4892fe388435 81 SPIName spi_sclk = (SPIName)pinmap_peripheral(sclk, PinMap_SPI_SCLK);
bogdanm 15:4892fe388435 82 SPIName spi_ssel = (SPIName)pinmap_peripheral(ssel, PinMap_SPI_SSEL);
bogdanm 15:4892fe388435 83 SPIName spi_data = (SPIName)pinmap_merge(spi_mosi, spi_miso);
bogdanm 15:4892fe388435 84 SPIName spi_cntl = (SPIName)pinmap_merge(spi_sclk, spi_ssel);
bogdanm 15:4892fe388435 85
bogdanm 15:4892fe388435 86 obj->spi = (SPI_Type*)pinmap_merge(spi_data, spi_cntl);
bogdanm 15:4892fe388435 87 if ((int)obj->spi == NC) {
bogdanm 15:4892fe388435 88 error("SPI pinout mapping failed");
bogdanm 15:4892fe388435 89 }
bogdanm 15:4892fe388435 90
bogdanm 15:4892fe388435 91 // enable power and clocking
bogdanm 15:4892fe388435 92 switch ((int)obj->spi) {
bogdanm 15:4892fe388435 93 case SPI_0: SIM->SCGC5 |= 1 << 11; SIM->SCGC4 |= 1 << 22; break;
bogdanm 15:4892fe388435 94 case SPI_1: SIM->SCGC5 |= 1 << 13; SIM->SCGC4 |= 1 << 23; break;
bogdanm 15:4892fe388435 95 }
bogdanm 15:4892fe388435 96
bogdanm 15:4892fe388435 97 // set default format and frequency
bogdanm 15:4892fe388435 98 if (ssel == NC) {
bogdanm 15:4892fe388435 99 spi_format(obj, 8, 0, 0); // 8 bits, mode 0, master
bogdanm 15:4892fe388435 100 } else {
bogdanm 15:4892fe388435 101 spi_format(obj, 8, 0, 1); // 8 bits, mode 0, slave
bogdanm 15:4892fe388435 102 }
bogdanm 15:4892fe388435 103 spi_frequency(obj, 1000000);
bogdanm 15:4892fe388435 104
bogdanm 15:4892fe388435 105 // enable SPI
bogdanm 15:4892fe388435 106 obj->spi->C1 |= SPI_C1_SPE_MASK;
bogdanm 15:4892fe388435 107
bogdanm 15:4892fe388435 108 // pin out the spi pins
bogdanm 15:4892fe388435 109 pinmap_pinout(mosi, PinMap_SPI_MOSI);
bogdanm 15:4892fe388435 110 pinmap_pinout(miso, PinMap_SPI_MISO);
bogdanm 15:4892fe388435 111 pinmap_pinout(sclk, PinMap_SPI_SCLK);
bogdanm 15:4892fe388435 112 if (ssel != NC) {
bogdanm 15:4892fe388435 113 pinmap_pinout(ssel, PinMap_SPI_SSEL);
bogdanm 15:4892fe388435 114 }
bogdanm 15:4892fe388435 115 }
bogdanm 15:4892fe388435 116
bogdanm 15:4892fe388435 117 void spi_free(spi_t *obj) {
bogdanm 15:4892fe388435 118 // [TODO]
bogdanm 15:4892fe388435 119 }
bogdanm 15:4892fe388435 120 void spi_format(spi_t *obj, int bits, int mode, int slave) {
bogdanm 15:4892fe388435 121 if (bits != 8) {
bogdanm 15:4892fe388435 122 error("Only 8bits SPI supported");
bogdanm 15:4892fe388435 123 }
bogdanm 15:4892fe388435 124
bogdanm 15:4892fe388435 125 if ((mode < 0) || (mode > 3)) {
bogdanm 15:4892fe388435 126 error("SPI mode unsupported");
bogdanm 15:4892fe388435 127 }
bogdanm 15:4892fe388435 128
bogdanm 15:4892fe388435 129 uint8_t polarity = (mode & 0x2) ? 1 : 0;
bogdanm 15:4892fe388435 130 uint8_t phase = (mode & 0x1) ? 1 : 0;
bogdanm 15:4892fe388435 131 uint8_t c1_data = ((!slave) << 4) | (polarity << 3) | (phase << 2);
bogdanm 15:4892fe388435 132
bogdanm 15:4892fe388435 133 // clear MSTR, CPOL and CPHA bits
bogdanm 15:4892fe388435 134 obj->spi->C1 &= ~(0x7 << 2);
bogdanm 15:4892fe388435 135
bogdanm 15:4892fe388435 136 // write new value
bogdanm 15:4892fe388435 137 obj->spi->C1 |= c1_data;
bogdanm 15:4892fe388435 138 }
bogdanm 15:4892fe388435 139
bogdanm 15:4892fe388435 140 void spi_frequency(spi_t *obj, int hz) {
bogdanm 15:4892fe388435 141 uint32_t error = 0;
bogdanm 15:4892fe388435 142 uint32_t p_error = 0xffffffff;
bogdanm 15:4892fe388435 143 uint32_t ref = 0;
bogdanm 15:4892fe388435 144 uint8_t spr = 0;
bogdanm 15:4892fe388435 145 uint8_t ref_spr = 0;
bogdanm 15:4892fe388435 146 uint8_t ref_prescaler = 0;
bogdanm 15:4892fe388435 147
bogdanm 15:4892fe388435 148 // bus clk
mbed_official 72:248c61396e08 149 uint32_t PCLK = bus_frequency();
bogdanm 15:4892fe388435 150 uint8_t prescaler = 1;
bogdanm 15:4892fe388435 151 uint8_t divisor = 2;
bogdanm 15:4892fe388435 152
bogdanm 15:4892fe388435 153 for (prescaler = 1; prescaler <= 8; prescaler++) {
bogdanm 15:4892fe388435 154 divisor = 2;
bogdanm 15:4892fe388435 155 for (spr = 0; spr <= 8; spr++, divisor *= 2) {
bogdanm 15:4892fe388435 156 ref = PCLK / (prescaler*divisor);
bogdanm 19:398f4c622e1b 157 if (ref > (uint32_t)hz)
bogdanm 15:4892fe388435 158 continue;
bogdanm 15:4892fe388435 159 error = hz - ref;
bogdanm 15:4892fe388435 160 if (error < p_error) {
bogdanm 15:4892fe388435 161 ref_spr = spr;
bogdanm 15:4892fe388435 162 ref_prescaler = prescaler - 1;
bogdanm 15:4892fe388435 163 p_error = error;
bogdanm 15:4892fe388435 164 }
bogdanm 15:4892fe388435 165 }
bogdanm 15:4892fe388435 166 }
bogdanm 15:4892fe388435 167
bogdanm 15:4892fe388435 168 // set SPPR and SPR
bogdanm 15:4892fe388435 169 obj->spi->BR = ((ref_prescaler & 0x7) << 4) | (ref_spr & 0xf);
bogdanm 15:4892fe388435 170 }
bogdanm 13:0645d8841f51 171
bogdanm 13:0645d8841f51 172 static inline int spi_writeable(spi_t * obj) {
bogdanm 13:0645d8841f51 173 return (obj->spi->S & SPI_S_SPTEF_MASK) ? 1 : 0;
bogdanm 13:0645d8841f51 174 }
bogdanm 13:0645d8841f51 175
bogdanm 13:0645d8841f51 176 static inline int spi_readable(spi_t * obj) {
bogdanm 13:0645d8841f51 177 return (obj->spi->S & SPI_S_SPRF_MASK) ? 1 : 0;
bogdanm 15:4892fe388435 178 }
bogdanm 15:4892fe388435 179
bogdanm 15:4892fe388435 180 int spi_master_write(spi_t *obj, int value) {
bogdanm 15:4892fe388435 181 // wait tx buffer empty
bogdanm 15:4892fe388435 182 while(!spi_writeable(obj));
bogdanm 15:4892fe388435 183 obj->spi->D = (value & 0xff);
bogdanm 15:4892fe388435 184
bogdanm 15:4892fe388435 185 // wait rx buffer full
bogdanm 15:4892fe388435 186 while (!spi_readable(obj));
bogdanm 15:4892fe388435 187 return obj->spi->D & 0xff;
bogdanm 13:0645d8841f51 188 }
bogdanm 13:0645d8841f51 189
bogdanm 13:0645d8841f51 190 int spi_slave_receive(spi_t *obj) {
bogdanm 13:0645d8841f51 191 return spi_readable(obj);
bogdanm 13:0645d8841f51 192 }
bogdanm 13:0645d8841f51 193
bogdanm 13:0645d8841f51 194 int spi_slave_read(spi_t *obj) {
bogdanm 13:0645d8841f51 195 return obj->spi->D;
bogdanm 13:0645d8841f51 196 }
bogdanm 13:0645d8841f51 197
bogdanm 13:0645d8841f51 198 void spi_slave_write(spi_t *obj, int value) {
bogdanm 13:0645d8841f51 199 while (!spi_writeable(obj));
bogdanm 13:0645d8841f51 200 obj->spi->D = value;
bogdanm 15:4892fe388435 201 }