[LPC1549] Added SPI support

pull/182/head
Toyomasa Watarai 2014-02-13 16:52:38 +09:00
parent 78d4c7345b
commit 07706f0821
3 changed files with 218 additions and 2 deletions

View File

@ -10,3 +10,4 @@ LR_IROM1 0x00000000 0x40000 { ; load region size_region (256k)
RW_IRAM1 (0x02000000+0x100) (0x9000-0x100) {
.ANY (+RW +ZI)
}
}

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@ -31,8 +31,8 @@
#define DEVICE_I2C 0
#define DEVICE_I2CSLAVE 0
#define DEVICE_SPI 0
#define DEVICE_SPISLAVE 0
#define DEVICE_SPI 1
#define DEVICE_SPISLAVE 1
#define DEVICE_CAN 0

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@ -0,0 +1,215 @@
/* mbed Microcontroller Library
* Copyright (c) 2006-2013 ARM Limited
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <math.h>
#include "spi_api.h"
#include "cmsis.h"
#include "pinmap.h"
#include "error.h"
static const SWM_Map SWM_SPI_SSEL[] = {
{4, 0},
{5, 24},
};
static const SWM_Map SWM_SPI_SCLK[] = {
{3, 8},
{5, 0},
};
static const SWM_Map SWM_SPI_MOSI[] = {
{3, 16},
{5, 8},
};
static const SWM_Map SWM_SPI_MISO[] = {
{3, 24},
{5, 16},
};
// bit flags for used SPIs
static unsigned char spi_used = 0;
static int get_available_spi(void) {
int i;
for (i=0; i<2; i++) {
if ((spi_used & (1 << i)) == 0)
return i;
}
return -1;
}
static inline void spi_disable(spi_t *obj);
static inline void spi_enable(spi_t *obj);
void spi_init(spi_t *obj, PinName mosi, PinName miso, PinName sclk, PinName ssel) {
int spi_n = get_available_spi();
if (spi_n == -1) {
error("No available SPI");
}
obj->spi_n = spi_n;
spi_used |= (1 << spi_n);
obj->spi = (spi_n) ? (LPC_SPI0_Type *)(LPC_SPI1_BASE) : (LPC_SPI0_Type *)(LPC_SPI0_BASE);
const SWM_Map *swm;
uint32_t regVal;
if (sclk != NC) {
swm = &SWM_SPI_SCLK[obj->spi_n];
regVal = LPC_SWM->PINASSIGN[swm->n] & ~(0xFF << swm->offset);
LPC_SWM->PINASSIGN[swm->n] = regVal | (sclk << swm->offset);
}
if (mosi != NC) {
swm = &SWM_SPI_MOSI[obj->spi_n];
regVal = LPC_SWM->PINASSIGN[swm->n] & ~(0xFF << swm->offset);
LPC_SWM->PINASSIGN[swm->n] = regVal | (mosi << swm->offset);
}
if (miso != NC) {
swm = &SWM_SPI_MISO[obj->spi_n];
regVal = LPC_SWM->PINASSIGN[swm->n] & ~(0xFF << swm->offset);
LPC_SWM->PINASSIGN[swm->n] = regVal | (miso << swm->offset);
}
if (ssel != NC) {
swm = &SWM_SPI_SSEL[obj->spi_n];
regVal = LPC_SWM->PINASSIGN[swm->n] & ~(0xFF << swm->offset);
LPC_SWM->PINASSIGN[swm->n] = regVal | (ssel << swm->offset);
}
// clear interrupts
obj->spi->INTENCLR = 0x3f;
// enable power and clocking
switch (obj->spi_n) {
case 0:
LPC_SYSCON->SYSAHBCLKCTRL1 |= (0x1<<9);
LPC_SYSCON->PRESETCTRL1 |= (0x1<<9);
LPC_SYSCON->PRESETCTRL1 &= ~(0x1<<9);
break;
case 1:
LPC_SYSCON->SYSAHBCLKCTRL1 |= (0x1<<10);
LPC_SYSCON->PRESETCTRL1 |= (0x1<<10);
LPC_SYSCON->PRESETCTRL1 &= ~(0x1<<10);
break;
}
// set default format and frequency
if (ssel == NC) {
spi_format(obj, 8, 0, 0); // 8 bits, mode 0, master
} else {
spi_format(obj, 8, 0, 1); // 8 bits, mode 0, slave
}
spi_frequency(obj, 1000000);
// enable the spi channel
spi_enable(obj);
}
void spi_free(spi_t *obj) {}
void spi_format(spi_t *obj, int bits, int mode, int slave) {
spi_disable(obj);
if (!(bits >= 1 && bits <= 16) || !(mode >= 0 && mode <= 3)) {
error("SPI format error");
}
int polarity = (mode & 0x2) ? 1 : 0;
int phase = (mode & 0x1) ? 1 : 0;
// set it up
int LEN = bits - 1; // LEN - Data Length
int CPOL = (polarity) ? 1 : 0; // CPOL - Clock Polarity select
int CPHA = (phase) ? 1 : 0; // CPHA - Clock Phase select
uint32_t tmp = obj->spi->CFG;
tmp &= ~((1 << 5) | (1 << 4) | (1 << 2));
tmp |= (CPOL << 5) | (CPHA << 4) | ((slave ? 0 : 1) << 2);
obj->spi->CFG = tmp;
// select frame length
tmp = obj->spi->TXDATCTL;
tmp &= ~(0xf << 24);
tmp |= (LEN << 24);
obj->spi->TXDATCTL = tmp;
spi_enable(obj);
}
void spi_frequency(spi_t *obj, int hz) {
spi_disable(obj);
uint32_t PCLK = SystemCoreClock;
obj->spi->DIV = PCLK/hz - 1;
obj->spi->DLY = 0;
spi_enable(obj);
}
static inline void spi_disable(spi_t *obj) {
obj->spi->CFG &= ~(1 << 0);
}
static inline void spi_enable(spi_t *obj) {
obj->spi->CFG |= (1 << 0);
}
static inline int spi_readable(spi_t *obj) {
return obj->spi->STAT & (1 << 0);
}
static inline int spi_writeable(spi_t *obj) {
return obj->spi->STAT & (1 << 1);
}
static inline void spi_write(spi_t *obj, int value) {
while (!spi_writeable(obj));
// end of transfer
obj->spi->TXDATCTL |= (1 << 20);
obj->spi->TXDAT = value;
}
static inline int spi_read(spi_t *obj) {
while (!spi_readable(obj));
return obj->spi->RXDAT;
}
static inline int spi_busy(spi_t *obj) {
// checking RXOV(Receiver Overrun interrupt flag)
return obj->spi->STAT & (1 << 2);
}
int spi_master_write(spi_t *obj, int value) {
spi_write(obj, value);
return spi_read(obj);
}
int spi_slave_receive(spi_t *obj) {
return (spi_readable(obj) && !spi_busy(obj)) ? (1) : (0);
}
int spi_slave_read(spi_t *obj) {
return obj->spi->RXDAT;
}
void spi_slave_write(spi_t *obj, int value) {
while (spi_writeable(obj) == 0) ;
obj->spi->TXDAT = value;
}