mbed w/ spi bug fig
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Diff: vendor/Freescale/KL25Z/hal/spi_api.c
- Revision:
- 13:0645d8841f51
- Parent:
- 12:5fa2273de5db
- Child:
- 14:096882eb0961
--- a/vendor/Freescale/KL25Z/hal/spi_api.c Wed Jul 24 11:11:21 2013 +0100 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000 @@ -1,175 +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 "spi_api.h" - -#include <math.h> - -#include "cmsis.h" -#include "pinmap.h" -#include "error.h" - -static const PinMap PinMap_SPI_SCLK[] = { - {PTE2, SPI_1, 2}, - {PTC5, SPI_0, 2}, - {PTD1, SPI_0, 2}, - {NC , NC , 0} -}; - -static const PinMap PinMap_SPI_MOSI[] = { - {PTE1, SPI_1, 2}, - {PTC6, SPI_0, 2}, - {PTD2, SPI_0, 2}, - {NC , NC , 0} -}; - -static const PinMap PinMap_SPI_MISO[] = { - {PTE3, SPI_1, 2}, - {PTC7, SPI_0, 2}, - {PTD3, SPI_0, 2}, - {NC , NC , 0} -}; - -static const PinMap PinMap_SPI_SSEL[] = { - {PTE4, SPI_1, 2}, - {PTC4, SPI_0, 2}, - {PTD0, SPI_0, 2}, - {NC , NC , 0} -}; - -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 = (SPI_Type*)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: SIM->SCGC5 |= 1 << 11; SIM->SCGC4 |= 1 << 22; break; - case SPI_1: SIM->SCGC5 |= 1 << 13; SIM->SCGC4 |= 1 << 23; 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 SPI - obj->spi->C1 |= SPI_C1_SPE_MASK; - - // 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) { - // [TODO] -} -void spi_format(spi_t *obj, int bits, int mode, int slave) { - if (bits != 8) { - error("Only 8bits SPI supported"); - } - - if ((mode < 0) || (mode > 3)) { - error("SPI mode unsupported"); - } - - uint8_t polarity = (mode & 0x2) ? 1 : 0; - uint8_t phase = (mode & 0x1) ? 1 : 0; - uint8_t c1_data = ((!slave) << 4) | (polarity << 3) | (phase << 2); - - // clear MSTR, CPOL and CPHA bits - obj->spi->C1 &= ~(0x7 << 2); - - // write new value - obj->spi->C1 |= c1_data; -} - -void spi_frequency(spi_t *obj, int hz) { - uint32_t error = 0; - uint32_t p_error = 0xffffffff; - uint32_t ref = 0; - uint8_t spr = 0; - uint8_t ref_spr = 0; - uint8_t ref_prescaler = 0; - - // bus clk - uint32_t PCLK = 48000000u; - uint8_t prescaler = 1; - uint8_t divisor = 2; - - for (prescaler = 1; prescaler <= 8; prescaler++) { - divisor = 2; - for (spr = 0; spr <= 8; spr++) { - ref = PCLK / (prescaler*divisor); - error = (ref > hz) ? ref - hz : hz - ref; - if (error < p_error) { - ref_spr = spr; - ref_prescaler = prescaler - 1; - p_error = error; - } - divisor *= 2; - } - } - - // set SPPR and SPR - obj->spi->BR = ((ref_prescaler & 0x7) << 4) | (ref_spr & 0xf); -} - -static inline int spi_writeable(spi_t * obj) { - return (obj->spi->S & SPI_S_SPTEF_MASK) ? 1 : 0; -} - -static inline int spi_readable(spi_t * obj) { - return (obj->spi->S & SPI_S_SPRF_MASK) ? 1 : 0; -} - -int spi_master_write(spi_t *obj, int value) { - // wait tx buffer empty - while(!spi_writeable(obj)); - obj->spi->D = (value & 0xff); - - // wait rx buffer full - while (!spi_readable(obj)); - return obj->spi->D & 0xff; -} - -int spi_slave_receive(spi_t *obj) { - return spi_readable(obj); -} - -int spi_slave_read(spi_t *obj) { - return obj->spi->D; -} - -void spi_slave_write(spi_t *obj, int value) { - while (!spi_writeable(obj)); - obj->spi->D = value; -}