shao ziyang / mbed-src-kl05

mbed library sources

Dependents:   frdm_kl05z_gpio_test

Fork of mbed-src by mbed official

targets/hal/TARGET_NXP/TARGET_LPC15XX/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:
222:96162ccfbf43
Child:
250:a49055e7a707
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 103:9b881da47c92 1 /* mbed Microcontroller Library
mbed_official 103:9b881da47c92 2 * Copyright (c) 2006-2013 ARM Limited
mbed_official 103:9b881da47c92 3 *
mbed_official 103:9b881da47c92 4 * Licensed under the Apache License, Version 2.0 (the "License");
mbed_official 103:9b881da47c92 5 * you may not use this file except in compliance with the License.
mbed_official 103:9b881da47c92 6 * You may obtain a copy of the License at
mbed_official 103:9b881da47c92 7 *
mbed_official 103:9b881da47c92 8 * http://www.apache.org/licenses/LICENSE-2.0
mbed_official 103:9b881da47c92 9 *
mbed_official 103:9b881da47c92 10 * Unless required by applicable law or agreed to in writing, software
mbed_official 103:9b881da47c92 11 * distributed under the License is distributed on an "AS IS" BASIS,
mbed_official 103:9b881da47c92 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
mbed_official 103:9b881da47c92 13 * See the License for the specific language governing permissions and
mbed_official 103:9b881da47c92 14 * limitations under the License.
mbed_official 103:9b881da47c92 15 */
mbed_official 227:7bd0639b8911 16 #include "mbed_assert.h"
mbed_official 103:9b881da47c92 17 #include <math.h>
mbed_official 103:9b881da47c92 18
mbed_official 103:9b881da47c92 19 #include "spi_api.h"
mbed_official 103:9b881da47c92 20 #include "cmsis.h"
mbed_official 103:9b881da47c92 21 #include "pinmap.h"
mbed_official 103:9b881da47c92 22 #include "error.h"
mbed_official 103:9b881da47c92 23
mbed_official 103:9b881da47c92 24 static const SWM_Map SWM_SPI_SSEL[] = {
mbed_official 103:9b881da47c92 25 {4, 0},
mbed_official 103:9b881da47c92 26 {5, 24},
mbed_official 103:9b881da47c92 27 };
mbed_official 103:9b881da47c92 28
mbed_official 103:9b881da47c92 29 static const SWM_Map SWM_SPI_SCLK[] = {
mbed_official 103:9b881da47c92 30 {3, 8},
mbed_official 103:9b881da47c92 31 {5, 0},
mbed_official 103:9b881da47c92 32 };
mbed_official 103:9b881da47c92 33
mbed_official 103:9b881da47c92 34 static const SWM_Map SWM_SPI_MOSI[] = {
mbed_official 103:9b881da47c92 35 {3, 16},
mbed_official 103:9b881da47c92 36 {5, 8},
mbed_official 103:9b881da47c92 37 };
mbed_official 103:9b881da47c92 38
mbed_official 103:9b881da47c92 39 static const SWM_Map SWM_SPI_MISO[] = {
mbed_official 103:9b881da47c92 40 {3, 24},
mbed_official 103:9b881da47c92 41 {5, 16},
mbed_official 103:9b881da47c92 42 };
mbed_official 103:9b881da47c92 43
mbed_official 103:9b881da47c92 44 // bit flags for used SPIs
mbed_official 103:9b881da47c92 45 static unsigned char spi_used = 0;
mbed_official 103:9b881da47c92 46 static int get_available_spi(void) {
mbed_official 103:9b881da47c92 47 int i;
mbed_official 103:9b881da47c92 48 for (i=0; i<2; i++) {
mbed_official 103:9b881da47c92 49 if ((spi_used & (1 << i)) == 0)
mbed_official 103:9b881da47c92 50 return i;
mbed_official 103:9b881da47c92 51 }
mbed_official 103:9b881da47c92 52 return -1;
mbed_official 103:9b881da47c92 53 }
mbed_official 103:9b881da47c92 54
mbed_official 103:9b881da47c92 55 static inline void spi_disable(spi_t *obj);
mbed_official 103:9b881da47c92 56 static inline void spi_enable(spi_t *obj);
mbed_official 103:9b881da47c92 57
mbed_official 103:9b881da47c92 58 void spi_init(spi_t *obj, PinName mosi, PinName miso, PinName sclk, PinName ssel) {
mbed_official 103:9b881da47c92 59 int spi_n = get_available_spi();
mbed_official 103:9b881da47c92 60 if (spi_n == -1) {
mbed_official 103:9b881da47c92 61 error("No available SPI");
mbed_official 103:9b881da47c92 62 }
mbed_official 103:9b881da47c92 63
mbed_official 103:9b881da47c92 64 obj->spi_n = spi_n;
mbed_official 103:9b881da47c92 65 spi_used |= (1 << spi_n);
mbed_official 103:9b881da47c92 66
mbed_official 103:9b881da47c92 67 obj->spi = (spi_n) ? (LPC_SPI0_Type *)(LPC_SPI1_BASE) : (LPC_SPI0_Type *)(LPC_SPI0_BASE);
mbed_official 103:9b881da47c92 68
mbed_official 103:9b881da47c92 69 const SWM_Map *swm;
mbed_official 103:9b881da47c92 70 uint32_t regVal;
mbed_official 103:9b881da47c92 71
mbed_official 103:9b881da47c92 72 if (sclk != NC) {
mbed_official 103:9b881da47c92 73 swm = &SWM_SPI_SCLK[obj->spi_n];
mbed_official 103:9b881da47c92 74 regVal = LPC_SWM->PINASSIGN[swm->n] & ~(0xFF << swm->offset);
mbed_official 103:9b881da47c92 75 LPC_SWM->PINASSIGN[swm->n] = regVal | (sclk << swm->offset);
mbed_official 103:9b881da47c92 76 }
mbed_official 103:9b881da47c92 77
mbed_official 103:9b881da47c92 78 if (mosi != NC) {
mbed_official 103:9b881da47c92 79 swm = &SWM_SPI_MOSI[obj->spi_n];
mbed_official 103:9b881da47c92 80 regVal = LPC_SWM->PINASSIGN[swm->n] & ~(0xFF << swm->offset);
mbed_official 103:9b881da47c92 81 LPC_SWM->PINASSIGN[swm->n] = regVal | (mosi << swm->offset);
mbed_official 103:9b881da47c92 82 }
mbed_official 103:9b881da47c92 83
mbed_official 103:9b881da47c92 84 if (miso != NC) {
mbed_official 103:9b881da47c92 85 swm = &SWM_SPI_MISO[obj->spi_n];
mbed_official 103:9b881da47c92 86 regVal = LPC_SWM->PINASSIGN[swm->n] & ~(0xFF << swm->offset);
mbed_official 103:9b881da47c92 87 LPC_SWM->PINASSIGN[swm->n] = regVal | (miso << swm->offset);
mbed_official 103:9b881da47c92 88 }
mbed_official 103:9b881da47c92 89
mbed_official 103:9b881da47c92 90 if (ssel != NC) {
mbed_official 103:9b881da47c92 91 swm = &SWM_SPI_SSEL[obj->spi_n];
mbed_official 103:9b881da47c92 92 regVal = LPC_SWM->PINASSIGN[swm->n] & ~(0xFF << swm->offset);
mbed_official 103:9b881da47c92 93 LPC_SWM->PINASSIGN[swm->n] = regVal | (ssel << swm->offset);
mbed_official 103:9b881da47c92 94 }
mbed_official 103:9b881da47c92 95
mbed_official 103:9b881da47c92 96 // clear interrupts
mbed_official 103:9b881da47c92 97 obj->spi->INTENCLR = 0x3f;
mbed_official 103:9b881da47c92 98
mbed_official 103:9b881da47c92 99 // enable power and clocking
mbed_official 103:9b881da47c92 100
mbed_official 103:9b881da47c92 101 switch (obj->spi_n) {
mbed_official 103:9b881da47c92 102 case 0:
mbed_official 103:9b881da47c92 103 LPC_SYSCON->SYSAHBCLKCTRL1 |= (0x1<<9);
mbed_official 103:9b881da47c92 104 LPC_SYSCON->PRESETCTRL1 |= (0x1<<9);
mbed_official 103:9b881da47c92 105 LPC_SYSCON->PRESETCTRL1 &= ~(0x1<<9);
mbed_official 103:9b881da47c92 106 break;
mbed_official 103:9b881da47c92 107 case 1:
mbed_official 103:9b881da47c92 108 LPC_SYSCON->SYSAHBCLKCTRL1 |= (0x1<<10);
mbed_official 103:9b881da47c92 109 LPC_SYSCON->PRESETCTRL1 |= (0x1<<10);
mbed_official 103:9b881da47c92 110 LPC_SYSCON->PRESETCTRL1 &= ~(0x1<<10);
mbed_official 103:9b881da47c92 111 break;
mbed_official 103:9b881da47c92 112 }
mbed_official 103:9b881da47c92 113
mbed_official 103:9b881da47c92 114 // set default format and frequency
mbed_official 103:9b881da47c92 115 if (ssel == NC) {
mbed_official 103:9b881da47c92 116 spi_format(obj, 8, 0, 0); // 8 bits, mode 0, master
mbed_official 103:9b881da47c92 117 } else {
mbed_official 103:9b881da47c92 118 spi_format(obj, 8, 0, 1); // 8 bits, mode 0, slave
mbed_official 103:9b881da47c92 119 }
mbed_official 103:9b881da47c92 120 spi_frequency(obj, 1000000);
mbed_official 103:9b881da47c92 121
mbed_official 103:9b881da47c92 122 // enable the spi channel
mbed_official 103:9b881da47c92 123 spi_enable(obj);
mbed_official 103:9b881da47c92 124 }
mbed_official 103:9b881da47c92 125
mbed_official 103:9b881da47c92 126 void spi_free(spi_t *obj) {}
mbed_official 103:9b881da47c92 127
mbed_official 103:9b881da47c92 128 void spi_format(spi_t *obj, int bits, int mode, int slave) {
mbed_official 103:9b881da47c92 129 spi_disable(obj);
mbed_official 227:7bd0639b8911 130 MBED_ASSERT((bits >= 1 && bits <= 16) && (mode >= 0 && mode <= 3));
mbed_official 103:9b881da47c92 131
mbed_official 103:9b881da47c92 132 int polarity = (mode & 0x2) ? 1 : 0;
mbed_official 103:9b881da47c92 133 int phase = (mode & 0x1) ? 1 : 0;
mbed_official 103:9b881da47c92 134
mbed_official 103:9b881da47c92 135 // set it up
mbed_official 103:9b881da47c92 136 int LEN = bits - 1; // LEN - Data Length
mbed_official 103:9b881da47c92 137 int CPOL = (polarity) ? 1 : 0; // CPOL - Clock Polarity select
mbed_official 103:9b881da47c92 138 int CPHA = (phase) ? 1 : 0; // CPHA - Clock Phase select
mbed_official 103:9b881da47c92 139
mbed_official 103:9b881da47c92 140 uint32_t tmp = obj->spi->CFG;
mbed_official 103:9b881da47c92 141 tmp &= ~((1 << 5) | (1 << 4) | (1 << 2));
mbed_official 103:9b881da47c92 142 tmp |= (CPOL << 5) | (CPHA << 4) | ((slave ? 0 : 1) << 2);
mbed_official 103:9b881da47c92 143 obj->spi->CFG = tmp;
mbed_official 103:9b881da47c92 144
mbed_official 103:9b881da47c92 145 // select frame length
mbed_official 103:9b881da47c92 146 tmp = obj->spi->TXDATCTL;
mbed_official 103:9b881da47c92 147 tmp &= ~(0xf << 24);
mbed_official 103:9b881da47c92 148 tmp |= (LEN << 24);
mbed_official 103:9b881da47c92 149 obj->spi->TXDATCTL = tmp;
mbed_official 103:9b881da47c92 150
mbed_official 103:9b881da47c92 151 spi_enable(obj);
mbed_official 103:9b881da47c92 152 }
mbed_official 103:9b881da47c92 153
mbed_official 103:9b881da47c92 154 void spi_frequency(spi_t *obj, int hz) {
mbed_official 103:9b881da47c92 155 spi_disable(obj);
mbed_official 103:9b881da47c92 156
mbed_official 103:9b881da47c92 157 uint32_t PCLK = SystemCoreClock;
mbed_official 103:9b881da47c92 158
mbed_official 103:9b881da47c92 159 obj->spi->DIV = PCLK/hz - 1;
mbed_official 103:9b881da47c92 160 obj->spi->DLY = 0;
mbed_official 103:9b881da47c92 161 spi_enable(obj);
mbed_official 103:9b881da47c92 162 }
mbed_official 103:9b881da47c92 163
mbed_official 103:9b881da47c92 164 static inline void spi_disable(spi_t *obj) {
mbed_official 103:9b881da47c92 165 obj->spi->CFG &= ~(1 << 0);
mbed_official 103:9b881da47c92 166 }
mbed_official 103:9b881da47c92 167
mbed_official 103:9b881da47c92 168 static inline void spi_enable(spi_t *obj) {
mbed_official 103:9b881da47c92 169 obj->spi->CFG |= (1 << 0);
mbed_official 103:9b881da47c92 170 }
mbed_official 103:9b881da47c92 171
mbed_official 103:9b881da47c92 172 static inline int spi_readable(spi_t *obj) {
mbed_official 103:9b881da47c92 173 return obj->spi->STAT & (1 << 0);
mbed_official 103:9b881da47c92 174 }
mbed_official 103:9b881da47c92 175
mbed_official 103:9b881da47c92 176 static inline int spi_writeable(spi_t *obj) {
mbed_official 103:9b881da47c92 177 return obj->spi->STAT & (1 << 1);
mbed_official 103:9b881da47c92 178 }
mbed_official 103:9b881da47c92 179
mbed_official 103:9b881da47c92 180 static inline void spi_write(spi_t *obj, int value) {
mbed_official 103:9b881da47c92 181 while (!spi_writeable(obj));
mbed_official 103:9b881da47c92 182 // end of transfer
mbed_official 103:9b881da47c92 183 obj->spi->TXDATCTL |= (1 << 20);
mbed_official 103:9b881da47c92 184 obj->spi->TXDAT = value;
mbed_official 103:9b881da47c92 185 }
mbed_official 103:9b881da47c92 186
mbed_official 103:9b881da47c92 187 static inline int spi_read(spi_t *obj) {
mbed_official 103:9b881da47c92 188 while (!spi_readable(obj));
mbed_official 103:9b881da47c92 189 return obj->spi->RXDAT;
mbed_official 103:9b881da47c92 190 }
mbed_official 103:9b881da47c92 191
mbed_official 222:96162ccfbf43 192 int spi_busy(spi_t *obj) {
mbed_official 103:9b881da47c92 193 // checking RXOV(Receiver Overrun interrupt flag)
mbed_official 103:9b881da47c92 194 return obj->spi->STAT & (1 << 2);
mbed_official 103:9b881da47c92 195 }
mbed_official 103:9b881da47c92 196
mbed_official 103:9b881da47c92 197 int spi_master_write(spi_t *obj, int value) {
mbed_official 103:9b881da47c92 198 spi_write(obj, value);
mbed_official 103:9b881da47c92 199 return spi_read(obj);
mbed_official 103:9b881da47c92 200 }
mbed_official 103:9b881da47c92 201
mbed_official 103:9b881da47c92 202 int spi_slave_receive(spi_t *obj) {
mbed_official 103:9b881da47c92 203 return (spi_readable(obj) && !spi_busy(obj)) ? (1) : (0);
mbed_official 103:9b881da47c92 204 }
mbed_official 103:9b881da47c92 205
mbed_official 103:9b881da47c92 206 int spi_slave_read(spi_t *obj) {
mbed_official 103:9b881da47c92 207 return obj->spi->RXDAT;
mbed_official 103:9b881da47c92 208 }
mbed_official 103:9b881da47c92 209
mbed_official 103:9b881da47c92 210 void spi_slave_write(spi_t *obj, int value) {
mbed_official 103:9b881da47c92 211 while (spi_writeable(obj) == 0) ;
mbed_official 103:9b881da47c92 212 obj->spi->TXDAT = value;
mbed_official 103:9b881da47c92 213 }