+++ /dev/null
-/* 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 "mbed_assert.h"
-#include <math.h>
-#include "spi_api.h"
-#include "cmsis.h"
-#include "pinmap.h"
-#include "mbed_error.h"
-
-static const PinMap PinMap_SPI_SCLK[] = {
- {P0_6 , SPI_0, 0x02},
- {P0_10, SPI_0, 0x02},
- {P1_29, SPI_0, 0x01},
- {P1_15, SPI_1, 0x03},
- {P1_20, SPI_1, 0x02},
- {NC , NC , 0}
-};
-
-static const PinMap PinMap_SPI_MOSI[] = {
- {P0_9 , SPI_0, 0x01},
- {P0_21, SPI_1, 0x02},
- {P1_22, SPI_1, 0x02},
- {NC , NC , 0}
-};
-
-static const PinMap PinMap_SPI_MISO[] = {
- {P0_8 , SPI_0, 0x01},
- {P0_22, SPI_1, 0x03},
- {P1_21, SPI_1, 0x02},
- {NC , NC , 0}
-};
-
-static const PinMap PinMap_SPI_SSEL[] = {
- {P0_2 , SPI_0, 0x01},
- {P1_19, SPI_1, 0x02},
- {P1_23, SPI_1, 0x02},
- {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_SSPx_Type*)pinmap_merge(spi_data, spi_cntl);
- MBED_ASSERT((int)obj->spi != NC);
-
- // enable power and clocking
- switch ((int)obj->spi) {
- case SPI_0:
- LPC_SYSCON->SYSAHBCLKCTRL |= 1 << 11;
- LPC_SYSCON->SSP0CLKDIV = 0x01;
- LPC_SYSCON->PRESETCTRL |= 1 << 0;
- break;
- case SPI_1:
- LPC_SYSCON->SYSAHBCLKCTRL |= 1 << 18;
- LPC_SYSCON->SSP1CLKDIV = 0x01;
- LPC_SYSCON->PRESETCTRL |= 1 << 2;
- 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);
- MBED_ASSERT((bits >= 4 && bits <= 16) || (mode >= 0 && mode <= 3));
-
- 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);
-
- 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);
-}
projects / qmk_firmware.git / blobdiff