Diff: targets/hal/TARGET_NXP/TARGET_LPC176X/spi_api.c

Revision:

43:b3acfef78949

Parent:

42:7ca0bbba899b

--- a/targets/hal/TARGET_NXP/TARGET_LPC176X/spi_api.c	Sun Oct 27 16:30:04 2013 +0000
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,222 +0,0 @@
-/* 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 PinMap PinMap_SPI_SCLK[] = {
-    {P0_7 , SPI_1, 2},
-    {P0_15, SPI_0, 2},
-    {P1_20, SPI_0, 3},
-    {P1_31, SPI_1, 2},
-    {NC   , NC   , 0}
-};
-
-static const PinMap PinMap_SPI_MOSI[] = {
-    {P0_9 , SPI_1, 2},
-    {P0_13, SPI_1, 2},
-    {P0_18, SPI_0, 2},
-    {P1_24, SPI_0, 3},
-    {NC   , NC   , 0}
-};
-
-static const PinMap PinMap_SPI_MISO[] = {
-    {P0_8 , SPI_1, 2},
-    {P0_12, SPI_1, 2},
-    {P0_17, SPI_0, 2},
-    {P1_23, SPI_0, 3},
-    {NC   , NC   , 0}
-};
-
-static const PinMap PinMap_SPI_SSEL[] = {
-    {P0_6 , SPI_1, 2},
-    {P0_11, SPI_1, 2},
-    {P0_16, SPI_0, 2},
-    {P1_21, SPI_0, 3},
-    {NC   , NC   , 0}
-};
-
-static inline int ssp_disable(spi_t *obj);
-static inline int ssp_enable(spi_t *obj);
-
-void spi_init(spi_t *obj, PinName mosi, PinName miso, PinName sclk, PinName ssel) {
-    // determine the SPI to use
-    SPIName spi_mosi = (SPIName)pinmap_peripheral(mosi, PinMap_SPI_MOSI);
-    SPIName spi_miso = (SPIName)pinmap_peripheral(miso, PinMap_SPI_MISO);
-    SPIName spi_sclk = (SPIName)pinmap_peripheral(sclk, PinMap_SPI_SCLK);
-    SPIName spi_ssel = (SPIName)pinmap_peripheral(ssel, PinMap_SPI_SSEL);
-    SPIName spi_data = (SPIName)pinmap_merge(spi_mosi, spi_miso);
-    SPIName spi_cntl = (SPIName)pinmap_merge(spi_sclk, spi_ssel);
-    obj->spi = (LPC_SSP_TypeDef*)pinmap_merge(spi_data, spi_cntl);
-    if ((int)obj->spi == NC) {
-        error("SPI pinout mapping failed");
-    }
-    
-    // enable power and clocking
-    switch ((int)obj->spi) {
-        case SPI_0: LPC_SC->PCONP |= 1 << 21; break;
-        case SPI_1: LPC_SC->PCONP |= 1 << 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 ssp channel
-    ssp_enable(obj);
-
-    // pin out the spi pins
-    pinmap_pinout(mosi, PinMap_SPI_MOSI);
-    pinmap_pinout(miso, PinMap_SPI_MISO);
-    pinmap_pinout(sclk, PinMap_SPI_SCLK);
-    if (ssel != NC) {
-        pinmap_pinout(ssel, PinMap_SPI_SSEL);
-    }
-}
-
-void spi_free(spi_t *obj) {}
-
-void spi_format(spi_t *obj, int bits, int mode, int slave) {
-    ssp_disable(obj);
-    if (!(bits >= 4 && 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 DSS = bits - 1;            // DSS (data select size)
-    int SPO = (polarity) ? 1 : 0;  // SPO - clock out polarity
-    int SPH = (phase) ? 1 : 0;     // SPH - clock out phase
-    
-    int FRF = 0;                   // FRF (frame format) = SPI
-    uint32_t tmp = obj->spi->CR0;
-    tmp &= ~(0xFFFF);
-    tmp |= DSS << 0
-        | FRF << 4
-        | SPO << 6
-        | SPH << 7;
-    obj->spi->CR0 = tmp;
-    
-    tmp = obj->spi->CR1;
-    tmp &= ~(0xD);
-    tmp |= 0 << 0                   // LBM - loop back mode - off
-        | ((slave) ? 1 : 0) << 2   // MS - master slave mode, 1 = slave
-        | 0 << 3;                  // SOD - slave output disable - na
-    obj->spi->CR1 = tmp;
-    
-    ssp_enable(obj);
-}
-
-void spi_frequency(spi_t *obj, int hz) {
-    ssp_disable(obj);
-    
-    // setup the spi clock diveder to /1
-    switch ((int)obj->spi) {
-        case SPI_0:
-            LPC_SC->PCLKSEL1 &= ~(3 << 10);
-            LPC_SC->PCLKSEL1 |=  (1 << 10);
-            break;
-        case SPI_1:
-            LPC_SC->PCLKSEL0 &= ~(3 << 20);
-            LPC_SC->PCLKSEL0 |=  (1 << 20);
-            break;
-    }
-    
-    uint32_t PCLK = SystemCoreClock;
-    
-    int prescaler;
-    
-    for (prescaler = 2; prescaler <= 254; prescaler += 2) {
-        int prescale_hz = PCLK / prescaler;
-        
-        // calculate the divider
-        int divider = floor(((float)prescale_hz / (float)hz) + 0.5f);
-        
-        // check we can support the divider
-        if (divider < 256) {
-            // prescaler
-            obj->spi->CPSR = prescaler;
-            
-            // divider
-            obj->spi->CR0 &= ~(0xFFFF << 8);
-            obj->spi->CR0 |= (divider - 1) << 8;
-            ssp_enable(obj);
-            return;
-        }
-    }
-    error("Couldn't setup requested SPI frequency");
-}
-
-static inline int ssp_disable(spi_t *obj) {
-    return obj->spi->CR1 &= ~(1 << 1);
-}
-
-static inline int ssp_enable(spi_t *obj) {
-    return obj->spi->CR1 |= (1 << 1);
-}
-
-static inline int ssp_readable(spi_t *obj) {
-    return obj->spi->SR & (1 << 2);
-}
-
-static inline int ssp_writeable(spi_t *obj) {
-    return obj->spi->SR & (1 << 1);
-}
-
-static inline void ssp_write(spi_t *obj, int value) {
-    while (!ssp_writeable(obj));
-    obj->spi->DR = value;
-}
-
-static inline int ssp_read(spi_t *obj) {
-    while (!ssp_readable(obj));
-    return obj->spi->DR;
-}
-
-static inline int ssp_busy(spi_t *obj) {
-    return (obj->spi->SR & (1 << 4)) ? (1) : (0);
-}
-
-int spi_master_write(spi_t *obj, int value) {
-    ssp_write(obj, value);
-    return ssp_read(obj);
-}
-
-int spi_slave_receive(spi_t *obj) {
-    return (ssp_readable(obj) && !ssp_busy(obj)) ? (1) : (0);
-};
-
-int spi_slave_read(spi_t *obj) {
-    return obj->spi->DR;
-}
-
-void spi_slave_write(spi_t *obj, int value) {
-    while (ssp_writeable(obj) == 0) ;
-    obj->spi->DR = value;
-}
-
-int spi_busy(spi_t *obj) {
-    return ssp_busy(obj);
-}