mirror of https://github.com/ARMmbed/mbed-os.git
[LPC1549] Added SPI support
parent
78d4c7345b
commit
07706f0821
|
@ -10,3 +10,4 @@ LR_IROM1 0x00000000 0x40000 { ; load region size_region (256k)
|
|||
RW_IRAM1 (0x02000000+0x100) (0x9000-0x100) {
|
||||
.ANY (+RW +ZI)
|
||||
}
|
||||
}
|
||||
|
|
|
@ -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
|
||||
|
||||
|
|
|
@ -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;
|
||||
}
|
Loading…
Reference in New Issue