mbed library sources. Supersedes mbed-src.
Fork of mbed by
targets/hal/TARGET_WIZNET/TARGET_W7500x/spi_api.c@0:9b334a45a8ff, 2015-10-01 (annotated)
- Committer:
- bogdanm
- Date:
- Thu Oct 01 15:25:22 2015 +0300
- Revision:
- 0:9b334a45a8ff
- Child:
- 144:ef7eb2e8f9f7
Initial commit on mbed-dev
Replaces mbed-src (now inactive)
Who changed what in which revision?
User | Revision | Line number | New contents of line |
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bogdanm | 0:9b334a45a8ff | 1 | /* mbed Microcontroller Library |
bogdanm | 0:9b334a45a8ff | 2 | ******************************************************************************* |
bogdanm | 0:9b334a45a8ff | 3 | * Copyright (c) 2015 WIZnet Co.,Ltd. All rights reserved. |
bogdanm | 0:9b334a45a8ff | 4 | * All rights reserved. |
bogdanm | 0:9b334a45a8ff | 5 | * |
bogdanm | 0:9b334a45a8ff | 6 | * Redistribution and use in source and binary forms, with or without |
bogdanm | 0:9b334a45a8ff | 7 | * modification, are permitted provided that the following conditions are met: |
bogdanm | 0:9b334a45a8ff | 8 | * |
bogdanm | 0:9b334a45a8ff | 9 | * 1. Redistributions of source code must retain the above copyright notice, |
bogdanm | 0:9b334a45a8ff | 10 | * this list of conditions and the following disclaimer. |
bogdanm | 0:9b334a45a8ff | 11 | * 2. Redistributions in binary form must reproduce the above copyright notice, |
bogdanm | 0:9b334a45a8ff | 12 | * this list of conditions and the following disclaimer in the documentation |
bogdanm | 0:9b334a45a8ff | 13 | * and/or other materials provided with the distribution. |
bogdanm | 0:9b334a45a8ff | 14 | * 3. Neither the name of ARM Limited nor the names of its contributors |
bogdanm | 0:9b334a45a8ff | 15 | * may be used to endorse or promote products derived from this software |
bogdanm | 0:9b334a45a8ff | 16 | * without specific prior written permission. |
bogdanm | 0:9b334a45a8ff | 17 | * |
bogdanm | 0:9b334a45a8ff | 18 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" |
bogdanm | 0:9b334a45a8ff | 19 | * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
bogdanm | 0:9b334a45a8ff | 20 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE |
bogdanm | 0:9b334a45a8ff | 21 | * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE |
bogdanm | 0:9b334a45a8ff | 22 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
bogdanm | 0:9b334a45a8ff | 23 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR |
bogdanm | 0:9b334a45a8ff | 24 | * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER |
bogdanm | 0:9b334a45a8ff | 25 | * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, |
bogdanm | 0:9b334a45a8ff | 26 | * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
bogdanm | 0:9b334a45a8ff | 27 | * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
bogdanm | 0:9b334a45a8ff | 28 | ******************************************************************************* |
bogdanm | 0:9b334a45a8ff | 29 | */ |
bogdanm | 0:9b334a45a8ff | 30 | |
bogdanm | 0:9b334a45a8ff | 31 | #include "mbed_assert.h" |
bogdanm | 0:9b334a45a8ff | 32 | #include <math.h> |
bogdanm | 0:9b334a45a8ff | 33 | |
bogdanm | 0:9b334a45a8ff | 34 | #include "spi_api.h" |
bogdanm | 0:9b334a45a8ff | 35 | #include "cmsis.h" |
bogdanm | 0:9b334a45a8ff | 36 | #include "pinmap.h" |
bogdanm | 0:9b334a45a8ff | 37 | #include "mbed_error.h" |
bogdanm | 0:9b334a45a8ff | 38 | #include "PeripheralPins.h" |
bogdanm | 0:9b334a45a8ff | 39 | |
bogdanm | 0:9b334a45a8ff | 40 | static inline int ssp_disable(spi_t *obj); |
bogdanm | 0:9b334a45a8ff | 41 | static inline int ssp_enable(spi_t *obj); |
bogdanm | 0:9b334a45a8ff | 42 | |
bogdanm | 0:9b334a45a8ff | 43 | void spi_init(spi_t *obj, PinName mosi, PinName miso, PinName sclk, PinName ssel) { |
bogdanm | 0:9b334a45a8ff | 44 | // determine the SPI to use |
bogdanm | 0:9b334a45a8ff | 45 | SPIName spi_mosi = (SPIName)pinmap_peripheral(mosi, PinMap_SPI_MOSI); |
bogdanm | 0:9b334a45a8ff | 46 | SPIName spi_miso = (SPIName)pinmap_peripheral(miso, PinMap_SPI_MISO); |
bogdanm | 0:9b334a45a8ff | 47 | SPIName spi_sclk = (SPIName)pinmap_peripheral(sclk, PinMap_SPI_SCLK); |
bogdanm | 0:9b334a45a8ff | 48 | SPIName spi_ssel = (SPIName)pinmap_peripheral(ssel, PinMap_SPI_SSEL); |
bogdanm | 0:9b334a45a8ff | 49 | SPIName spi_data = (SPIName)pinmap_merge(spi_mosi, spi_miso); |
bogdanm | 0:9b334a45a8ff | 50 | SPIName spi_cntl = (SPIName)pinmap_merge(spi_sclk, spi_ssel); |
bogdanm | 0:9b334a45a8ff | 51 | obj->spi = (SSP_TypeDef*)pinmap_merge(spi_data, spi_cntl); |
bogdanm | 0:9b334a45a8ff | 52 | MBED_ASSERT((int)obj->spi != NC); |
bogdanm | 0:9b334a45a8ff | 53 | |
bogdanm | 0:9b334a45a8ff | 54 | // enable power and clocking |
bogdanm | 0:9b334a45a8ff | 55 | switch ((int)obj->spi) { |
bogdanm | 0:9b334a45a8ff | 56 | case SPI_0: CRG->SSPCLK_SSR = CRG_SSPCLK_SSR_MCLK; break; //PLL output clock |
bogdanm | 0:9b334a45a8ff | 57 | case SPI_1: CRG->SSPCLK_SSR = CRG_SSPCLK_SSR_MCLK; break; |
bogdanm | 0:9b334a45a8ff | 58 | } |
bogdanm | 0:9b334a45a8ff | 59 | |
bogdanm | 0:9b334a45a8ff | 60 | // set default format and frequency |
bogdanm | 0:9b334a45a8ff | 61 | if (ssel == NC) { |
bogdanm | 0:9b334a45a8ff | 62 | spi_format(obj, 8, 0, 0); // 8 bits, mode 0, master |
bogdanm | 0:9b334a45a8ff | 63 | } else { |
bogdanm | 0:9b334a45a8ff | 64 | spi_format(obj, 8, 0, 1); // 8 bits, mode 0, slave |
bogdanm | 0:9b334a45a8ff | 65 | } |
bogdanm | 0:9b334a45a8ff | 66 | spi_frequency(obj, 1000000); |
bogdanm | 0:9b334a45a8ff | 67 | |
bogdanm | 0:9b334a45a8ff | 68 | // enable the ssp channel |
bogdanm | 0:9b334a45a8ff | 69 | ssp_enable(obj); |
bogdanm | 0:9b334a45a8ff | 70 | |
bogdanm | 0:9b334a45a8ff | 71 | // pin out the spi pins |
bogdanm | 0:9b334a45a8ff | 72 | pinmap_pinout(mosi, PinMap_SPI_MOSI); |
bogdanm | 0:9b334a45a8ff | 73 | pinmap_pinout(miso, PinMap_SPI_MISO); |
bogdanm | 0:9b334a45a8ff | 74 | pinmap_pinout(sclk, PinMap_SPI_SCLK); |
bogdanm | 0:9b334a45a8ff | 75 | if (ssel != NC) { |
bogdanm | 0:9b334a45a8ff | 76 | pinmap_pinout(ssel, PinMap_SPI_SSEL); |
bogdanm | 0:9b334a45a8ff | 77 | } |
bogdanm | 0:9b334a45a8ff | 78 | } |
bogdanm | 0:9b334a45a8ff | 79 | |
bogdanm | 0:9b334a45a8ff | 80 | void spi_free(spi_t *obj) {} |
bogdanm | 0:9b334a45a8ff | 81 | |
bogdanm | 0:9b334a45a8ff | 82 | void spi_format(spi_t *obj, int bits, int mode, int slave) { |
bogdanm | 0:9b334a45a8ff | 83 | ssp_disable(obj); |
bogdanm | 0:9b334a45a8ff | 84 | MBED_ASSERT(((bits >= 4) && (bits <= 16)) && (mode >= 0 && mode <= 3)); |
bogdanm | 0:9b334a45a8ff | 85 | |
bogdanm | 0:9b334a45a8ff | 86 | int polarity = (mode & 0x2) ? 1 : 0; |
bogdanm | 0:9b334a45a8ff | 87 | int phase = (mode & 0x1) ? 1 : 0; |
bogdanm | 0:9b334a45a8ff | 88 | |
bogdanm | 0:9b334a45a8ff | 89 | // set it up |
bogdanm | 0:9b334a45a8ff | 90 | int DSS = bits - 1; // DSS (data select size) |
bogdanm | 0:9b334a45a8ff | 91 | int SPO = (polarity) ? 1 : 0; // SPO - clock out polarity |
bogdanm | 0:9b334a45a8ff | 92 | int SPH = (phase) ? 1 : 0; // SPH - clock out phase |
bogdanm | 0:9b334a45a8ff | 93 | |
bogdanm | 0:9b334a45a8ff | 94 | int FRF = 0; // FRF (frame format) = SPI |
bogdanm | 0:9b334a45a8ff | 95 | uint32_t tmp = obj->spi->CR0; |
bogdanm | 0:9b334a45a8ff | 96 | tmp &= ~(0xFFFF); |
bogdanm | 0:9b334a45a8ff | 97 | tmp |= DSS << 0 |
bogdanm | 0:9b334a45a8ff | 98 | | FRF << 4 |
bogdanm | 0:9b334a45a8ff | 99 | | SPO << 6 |
bogdanm | 0:9b334a45a8ff | 100 | | SPH << 7; |
bogdanm | 0:9b334a45a8ff | 101 | obj->spi->CR0 = tmp; |
bogdanm | 0:9b334a45a8ff | 102 | |
bogdanm | 0:9b334a45a8ff | 103 | tmp = obj->spi->CR1; |
bogdanm | 0:9b334a45a8ff | 104 | tmp &= ~(0xD); |
bogdanm | 0:9b334a45a8ff | 105 | tmp |= 0 << 0 // LBM - loop back mode - off |
bogdanm | 0:9b334a45a8ff | 106 | | ((slave) ? 1 : 0) << 2 // MS - master slave mode, 1 = slave |
bogdanm | 0:9b334a45a8ff | 107 | | 0 << 3; // SOD - slave output disable - na |
bogdanm | 0:9b334a45a8ff | 108 | obj->spi->CR1 = tmp; |
bogdanm | 0:9b334a45a8ff | 109 | |
bogdanm | 0:9b334a45a8ff | 110 | ssp_enable(obj); |
bogdanm | 0:9b334a45a8ff | 111 | } |
bogdanm | 0:9b334a45a8ff | 112 | |
bogdanm | 0:9b334a45a8ff | 113 | void spi_frequency(spi_t *obj, int hz) { |
bogdanm | 0:9b334a45a8ff | 114 | ssp_disable(obj); |
bogdanm | 0:9b334a45a8ff | 115 | |
bogdanm | 0:9b334a45a8ff | 116 | // setup the spi clock diveder to /1 |
bogdanm | 0:9b334a45a8ff | 117 | switch ((int)obj->spi) { |
bogdanm | 0:9b334a45a8ff | 118 | case SPI_0: |
bogdanm | 0:9b334a45a8ff | 119 | CRG->SSPCLK_PVSR = CRG_SSPCLK_PVSR_DIV1; //1/1 (bypass) |
bogdanm | 0:9b334a45a8ff | 120 | break; |
bogdanm | 0:9b334a45a8ff | 121 | case SPI_1: |
bogdanm | 0:9b334a45a8ff | 122 | CRG->SSPCLK_PVSR = CRG_SSPCLK_PVSR_DIV1; //1/1 (bypass) |
bogdanm | 0:9b334a45a8ff | 123 | break; |
bogdanm | 0:9b334a45a8ff | 124 | } |
bogdanm | 0:9b334a45a8ff | 125 | |
bogdanm | 0:9b334a45a8ff | 126 | uint32_t HCLK = SystemCoreClock; |
bogdanm | 0:9b334a45a8ff | 127 | |
bogdanm | 0:9b334a45a8ff | 128 | int prescaler; |
bogdanm | 0:9b334a45a8ff | 129 | |
bogdanm | 0:9b334a45a8ff | 130 | for (prescaler = 2; prescaler <= 254; prescaler += 2) { |
bogdanm | 0:9b334a45a8ff | 131 | int prescale_hz = HCLK / prescaler; |
bogdanm | 0:9b334a45a8ff | 132 | |
bogdanm | 0:9b334a45a8ff | 133 | // calculate the divider |
bogdanm | 0:9b334a45a8ff | 134 | int divider = floor(((float)prescale_hz / (float)hz) + 0.5f); |
bogdanm | 0:9b334a45a8ff | 135 | |
bogdanm | 0:9b334a45a8ff | 136 | // check we can support the divider |
bogdanm | 0:9b334a45a8ff | 137 | if (divider < 256) { |
bogdanm | 0:9b334a45a8ff | 138 | // prescaler |
bogdanm | 0:9b334a45a8ff | 139 | obj->spi->CPSR = prescaler; |
bogdanm | 0:9b334a45a8ff | 140 | |
bogdanm | 0:9b334a45a8ff | 141 | // divider |
bogdanm | 0:9b334a45a8ff | 142 | obj->spi->CR0 &= ~(0xFFFF << 8); |
bogdanm | 0:9b334a45a8ff | 143 | obj->spi->CR0 |= (divider - 1) << 8; |
bogdanm | 0:9b334a45a8ff | 144 | ssp_enable(obj); |
bogdanm | 0:9b334a45a8ff | 145 | return; |
bogdanm | 0:9b334a45a8ff | 146 | } |
bogdanm | 0:9b334a45a8ff | 147 | } |
bogdanm | 0:9b334a45a8ff | 148 | error("Couldn't setup requested SPI frequency"); |
bogdanm | 0:9b334a45a8ff | 149 | } |
bogdanm | 0:9b334a45a8ff | 150 | |
bogdanm | 0:9b334a45a8ff | 151 | static inline int ssp_disable(spi_t *obj) { |
bogdanm | 0:9b334a45a8ff | 152 | return obj->spi->CR1 &= ~(1 << 1); |
bogdanm | 0:9b334a45a8ff | 153 | } |
bogdanm | 0:9b334a45a8ff | 154 | |
bogdanm | 0:9b334a45a8ff | 155 | static inline int ssp_enable(spi_t *obj) { |
bogdanm | 0:9b334a45a8ff | 156 | return obj->spi->CR1 |= (1 << 1); |
bogdanm | 0:9b334a45a8ff | 157 | } |
bogdanm | 0:9b334a45a8ff | 158 | |
bogdanm | 0:9b334a45a8ff | 159 | static inline int ssp_readable(spi_t *obj) { |
bogdanm | 0:9b334a45a8ff | 160 | return obj->spi->SR & (1 << 2); |
bogdanm | 0:9b334a45a8ff | 161 | } |
bogdanm | 0:9b334a45a8ff | 162 | |
bogdanm | 0:9b334a45a8ff | 163 | static inline int ssp_writeable(spi_t *obj) { |
bogdanm | 0:9b334a45a8ff | 164 | return obj->spi->SR & (1 << 1); |
bogdanm | 0:9b334a45a8ff | 165 | } |
bogdanm | 0:9b334a45a8ff | 166 | |
bogdanm | 0:9b334a45a8ff | 167 | static inline void ssp_write(spi_t *obj, int value) { |
bogdanm | 0:9b334a45a8ff | 168 | while (!ssp_writeable(obj)); |
bogdanm | 0:9b334a45a8ff | 169 | obj->spi->DR = value; |
bogdanm | 0:9b334a45a8ff | 170 | } |
bogdanm | 0:9b334a45a8ff | 171 | |
bogdanm | 0:9b334a45a8ff | 172 | static inline int ssp_read(spi_t *obj) { |
bogdanm | 0:9b334a45a8ff | 173 | while (!ssp_readable(obj)); |
bogdanm | 0:9b334a45a8ff | 174 | return obj->spi->DR; |
bogdanm | 0:9b334a45a8ff | 175 | } |
bogdanm | 0:9b334a45a8ff | 176 | |
bogdanm | 0:9b334a45a8ff | 177 | static inline int ssp_busy(spi_t *obj) { |
bogdanm | 0:9b334a45a8ff | 178 | return (obj->spi->SR & (1 << 4)) ? (1) : (0); |
bogdanm | 0:9b334a45a8ff | 179 | } |
bogdanm | 0:9b334a45a8ff | 180 | |
bogdanm | 0:9b334a45a8ff | 181 | int spi_master_write(spi_t *obj, int value) { |
bogdanm | 0:9b334a45a8ff | 182 | ssp_write(obj, value); |
bogdanm | 0:9b334a45a8ff | 183 | return ssp_read(obj); |
bogdanm | 0:9b334a45a8ff | 184 | } |
bogdanm | 0:9b334a45a8ff | 185 | |
bogdanm | 0:9b334a45a8ff | 186 | int spi_slave_receive(spi_t *obj) { |
bogdanm | 0:9b334a45a8ff | 187 | return (ssp_readable(obj) && !ssp_busy(obj)) ? (1) : (0); |
bogdanm | 0:9b334a45a8ff | 188 | } |
bogdanm | 0:9b334a45a8ff | 189 | |
bogdanm | 0:9b334a45a8ff | 190 | int spi_slave_read(spi_t *obj) { |
bogdanm | 0:9b334a45a8ff | 191 | return obj->spi->DR; |
bogdanm | 0:9b334a45a8ff | 192 | } |
bogdanm | 0:9b334a45a8ff | 193 | |
bogdanm | 0:9b334a45a8ff | 194 | void spi_slave_write(spi_t *obj, int value) { |
bogdanm | 0:9b334a45a8ff | 195 | while (ssp_writeable(obj) == 0) ; |
bogdanm | 0:9b334a45a8ff | 196 | obj->spi->DR = value; |
bogdanm | 0:9b334a45a8ff | 197 | } |
bogdanm | 0:9b334a45a8ff | 198 | |
bogdanm | 0:9b334a45a8ff | 199 | int spi_busy(spi_t *obj) { |
bogdanm | 0:9b334a45a8ff | 200 | return ssp_busy(obj); |
bogdanm | 0:9b334a45a8ff | 201 | } |
bogdanm | 0:9b334a45a8ff | 202 |