mbed library sources. Supersedes mbed-src.
Dependents: Nucleo_Hello_Encoder BLE_iBeaconScan AM1805_DEMO DISCO-F429ZI_ExportTemplate1 ... more
targets/TARGET_Freescale/TARGET_KLXX/TARGET_KL25Z/spi_api.c@149:156823d33999, 2016-10-28 (annotated)
- Committer:
- <>
- Date:
- Fri Oct 28 11:17:30 2016 +0100
- Revision:
- 149:156823d33999
- Parent:
- targets/hal/TARGET_Freescale/TARGET_KLXX/TARGET_KL25Z/spi_api.c@144:ef7eb2e8f9f7
- Child:
- 167:e84263d55307
This updates the lib to the mbed lib v128
NOTE: This release includes a restructuring of the file and directory locations and thus some
include paths in your code may need updating accordingly.
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
<> | 144:ef7eb2e8f9f7 | 1 | /* mbed Microcontroller Library |
<> | 144:ef7eb2e8f9f7 | 2 | * Copyright (c) 2006-2013 ARM Limited |
<> | 144:ef7eb2e8f9f7 | 3 | * |
<> | 144:ef7eb2e8f9f7 | 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
<> | 144:ef7eb2e8f9f7 | 5 | * you may not use this file except in compliance with the License. |
<> | 144:ef7eb2e8f9f7 | 6 | * You may obtain a copy of the License at |
<> | 144:ef7eb2e8f9f7 | 7 | * |
<> | 144:ef7eb2e8f9f7 | 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
<> | 144:ef7eb2e8f9f7 | 9 | * |
<> | 144:ef7eb2e8f9f7 | 10 | * Unless required by applicable law or agreed to in writing, software |
<> | 144:ef7eb2e8f9f7 | 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
<> | 144:ef7eb2e8f9f7 | 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
<> | 144:ef7eb2e8f9f7 | 13 | * See the License for the specific language governing permissions and |
<> | 144:ef7eb2e8f9f7 | 14 | * limitations under the License. |
<> | 144:ef7eb2e8f9f7 | 15 | */ |
<> | 144:ef7eb2e8f9f7 | 16 | #include "spi_api.h" |
<> | 144:ef7eb2e8f9f7 | 17 | |
<> | 144:ef7eb2e8f9f7 | 18 | #include <math.h> |
<> | 144:ef7eb2e8f9f7 | 19 | |
<> | 144:ef7eb2e8f9f7 | 20 | #include "cmsis.h" |
<> | 144:ef7eb2e8f9f7 | 21 | #include "pinmap.h" |
<> | 144:ef7eb2e8f9f7 | 22 | #include "clk_freqs.h" |
<> | 144:ef7eb2e8f9f7 | 23 | #include "PeripheralPins.h" |
<> | 144:ef7eb2e8f9f7 | 24 | |
<> | 144:ef7eb2e8f9f7 | 25 | void spi_init(spi_t *obj, PinName mosi, PinName miso, PinName sclk, PinName ssel) { |
<> | 144:ef7eb2e8f9f7 | 26 | // determine the SPI to use |
<> | 144:ef7eb2e8f9f7 | 27 | SPIName spi_mosi = (SPIName)pinmap_peripheral(mosi, PinMap_SPI_MOSI); |
<> | 144:ef7eb2e8f9f7 | 28 | SPIName spi_miso = (SPIName)pinmap_peripheral(miso, PinMap_SPI_MISO); |
<> | 144:ef7eb2e8f9f7 | 29 | SPIName spi_sclk = (SPIName)pinmap_peripheral(sclk, PinMap_SPI_SCLK); |
<> | 144:ef7eb2e8f9f7 | 30 | SPIName spi_ssel = (SPIName)pinmap_peripheral(ssel, PinMap_SPI_SSEL); |
<> | 144:ef7eb2e8f9f7 | 31 | SPIName spi_data = (SPIName)pinmap_merge(spi_mosi, spi_miso); |
<> | 144:ef7eb2e8f9f7 | 32 | SPIName spi_cntl = (SPIName)pinmap_merge(spi_sclk, spi_ssel); |
<> | 144:ef7eb2e8f9f7 | 33 | |
<> | 144:ef7eb2e8f9f7 | 34 | obj->spi = (SPI_Type*)pinmap_merge(spi_data, spi_cntl); |
<> | 144:ef7eb2e8f9f7 | 35 | MBED_ASSERT((int)obj->spi != NC); |
<> | 144:ef7eb2e8f9f7 | 36 | |
<> | 144:ef7eb2e8f9f7 | 37 | // enable power and clocking |
<> | 144:ef7eb2e8f9f7 | 38 | switch ((int)obj->spi) { |
<> | 144:ef7eb2e8f9f7 | 39 | case SPI_0: SIM->SCGC5 |= 1 << 11; SIM->SCGC4 |= 1 << 22; break; |
<> | 144:ef7eb2e8f9f7 | 40 | case SPI_1: SIM->SCGC5 |= 1 << 13; SIM->SCGC4 |= 1 << 23; break; |
<> | 144:ef7eb2e8f9f7 | 41 | } |
<> | 144:ef7eb2e8f9f7 | 42 | |
<> | 144:ef7eb2e8f9f7 | 43 | // enable SPI |
<> | 144:ef7eb2e8f9f7 | 44 | obj->spi->C1 |= SPI_C1_SPE_MASK; |
<> | 144:ef7eb2e8f9f7 | 45 | |
<> | 144:ef7eb2e8f9f7 | 46 | // pin out the spi pins |
<> | 144:ef7eb2e8f9f7 | 47 | pinmap_pinout(mosi, PinMap_SPI_MOSI); |
<> | 144:ef7eb2e8f9f7 | 48 | pinmap_pinout(miso, PinMap_SPI_MISO); |
<> | 144:ef7eb2e8f9f7 | 49 | pinmap_pinout(sclk, PinMap_SPI_SCLK); |
<> | 144:ef7eb2e8f9f7 | 50 | if (ssel != NC) { |
<> | 144:ef7eb2e8f9f7 | 51 | pinmap_pinout(ssel, PinMap_SPI_SSEL); |
<> | 144:ef7eb2e8f9f7 | 52 | } |
<> | 144:ef7eb2e8f9f7 | 53 | } |
<> | 144:ef7eb2e8f9f7 | 54 | |
<> | 144:ef7eb2e8f9f7 | 55 | void spi_free(spi_t *obj) { |
<> | 144:ef7eb2e8f9f7 | 56 | // [TODO] |
<> | 144:ef7eb2e8f9f7 | 57 | } |
<> | 144:ef7eb2e8f9f7 | 58 | void spi_format(spi_t *obj, int bits, int mode, int slave) { |
<> | 144:ef7eb2e8f9f7 | 59 | MBED_ASSERT(bits == 8); |
<> | 144:ef7eb2e8f9f7 | 60 | MBED_ASSERT((mode >= 0) && (mode <= 3)); |
<> | 144:ef7eb2e8f9f7 | 61 | |
<> | 144:ef7eb2e8f9f7 | 62 | uint8_t polarity = (mode & 0x2) ? 1 : 0; |
<> | 144:ef7eb2e8f9f7 | 63 | uint8_t phase = (mode & 0x1) ? 1 : 0; |
<> | 144:ef7eb2e8f9f7 | 64 | uint8_t c1_data = ((!slave) << 4) | (polarity << 3) | (phase << 2); |
<> | 144:ef7eb2e8f9f7 | 65 | |
<> | 144:ef7eb2e8f9f7 | 66 | // clear MSTR, CPOL and CPHA bits |
<> | 144:ef7eb2e8f9f7 | 67 | obj->spi->C1 &= ~(0x7 << 2); |
<> | 144:ef7eb2e8f9f7 | 68 | |
<> | 144:ef7eb2e8f9f7 | 69 | // write new value |
<> | 144:ef7eb2e8f9f7 | 70 | obj->spi->C1 |= c1_data; |
<> | 144:ef7eb2e8f9f7 | 71 | } |
<> | 144:ef7eb2e8f9f7 | 72 | |
<> | 144:ef7eb2e8f9f7 | 73 | void spi_frequency(spi_t *obj, int hz) { |
<> | 144:ef7eb2e8f9f7 | 74 | uint32_t error = 0; |
<> | 144:ef7eb2e8f9f7 | 75 | uint32_t p_error = 0xffffffff; |
<> | 144:ef7eb2e8f9f7 | 76 | uint32_t ref = 0; |
<> | 144:ef7eb2e8f9f7 | 77 | uint8_t spr = 0; |
<> | 144:ef7eb2e8f9f7 | 78 | uint8_t ref_spr = 0; |
<> | 144:ef7eb2e8f9f7 | 79 | uint8_t ref_prescaler = 0; |
<> | 144:ef7eb2e8f9f7 | 80 | |
<> | 144:ef7eb2e8f9f7 | 81 | // bus clk |
<> | 144:ef7eb2e8f9f7 | 82 | uint32_t PCLK = bus_frequency(); |
<> | 144:ef7eb2e8f9f7 | 83 | uint8_t prescaler = 1; |
<> | 144:ef7eb2e8f9f7 | 84 | uint8_t divisor = 2; |
<> | 144:ef7eb2e8f9f7 | 85 | |
<> | 144:ef7eb2e8f9f7 | 86 | for (prescaler = 1; prescaler <= 8; prescaler++) { |
<> | 144:ef7eb2e8f9f7 | 87 | divisor = 2; |
<> | 144:ef7eb2e8f9f7 | 88 | for (spr = 0; spr <= 8; spr++, divisor *= 2) { |
<> | 144:ef7eb2e8f9f7 | 89 | ref = PCLK / (prescaler*divisor); |
<> | 144:ef7eb2e8f9f7 | 90 | if (ref > (uint32_t)hz) |
<> | 144:ef7eb2e8f9f7 | 91 | continue; |
<> | 144:ef7eb2e8f9f7 | 92 | error = hz - ref; |
<> | 144:ef7eb2e8f9f7 | 93 | if (error < p_error) { |
<> | 144:ef7eb2e8f9f7 | 94 | ref_spr = spr; |
<> | 144:ef7eb2e8f9f7 | 95 | ref_prescaler = prescaler - 1; |
<> | 144:ef7eb2e8f9f7 | 96 | p_error = error; |
<> | 144:ef7eb2e8f9f7 | 97 | } |
<> | 144:ef7eb2e8f9f7 | 98 | } |
<> | 144:ef7eb2e8f9f7 | 99 | } |
<> | 144:ef7eb2e8f9f7 | 100 | |
<> | 144:ef7eb2e8f9f7 | 101 | // set SPPR and SPR |
<> | 144:ef7eb2e8f9f7 | 102 | obj->spi->BR = ((ref_prescaler & 0x7) << 4) | (ref_spr & 0xf); |
<> | 144:ef7eb2e8f9f7 | 103 | } |
<> | 144:ef7eb2e8f9f7 | 104 | |
<> | 144:ef7eb2e8f9f7 | 105 | static inline int spi_writeable(spi_t * obj) { |
<> | 144:ef7eb2e8f9f7 | 106 | return (obj->spi->S & SPI_S_SPTEF_MASK) ? 1 : 0; |
<> | 144:ef7eb2e8f9f7 | 107 | } |
<> | 144:ef7eb2e8f9f7 | 108 | |
<> | 144:ef7eb2e8f9f7 | 109 | static inline int spi_readable(spi_t * obj) { |
<> | 144:ef7eb2e8f9f7 | 110 | return (obj->spi->S & SPI_S_SPRF_MASK) ? 1 : 0; |
<> | 144:ef7eb2e8f9f7 | 111 | } |
<> | 144:ef7eb2e8f9f7 | 112 | |
<> | 144:ef7eb2e8f9f7 | 113 | int spi_master_write(spi_t *obj, int value) { |
<> | 144:ef7eb2e8f9f7 | 114 | // wait tx buffer empty |
<> | 144:ef7eb2e8f9f7 | 115 | while(!spi_writeable(obj)); |
<> | 144:ef7eb2e8f9f7 | 116 | obj->spi->D = (value & 0xff); |
<> | 144:ef7eb2e8f9f7 | 117 | |
<> | 144:ef7eb2e8f9f7 | 118 | // wait rx buffer full |
<> | 144:ef7eb2e8f9f7 | 119 | while (!spi_readable(obj)); |
<> | 144:ef7eb2e8f9f7 | 120 | return obj->spi->D & 0xff; |
<> | 144:ef7eb2e8f9f7 | 121 | } |
<> | 144:ef7eb2e8f9f7 | 122 | |
<> | 144:ef7eb2e8f9f7 | 123 | int spi_slave_receive(spi_t *obj) { |
<> | 144:ef7eb2e8f9f7 | 124 | return spi_readable(obj); |
<> | 144:ef7eb2e8f9f7 | 125 | } |
<> | 144:ef7eb2e8f9f7 | 126 | |
<> | 144:ef7eb2e8f9f7 | 127 | int spi_slave_read(spi_t *obj) { |
<> | 144:ef7eb2e8f9f7 | 128 | return obj->spi->D; |
<> | 144:ef7eb2e8f9f7 | 129 | } |
<> | 144:ef7eb2e8f9f7 | 130 | |
<> | 144:ef7eb2e8f9f7 | 131 | void spi_slave_write(spi_t *obj, int value) { |
<> | 144:ef7eb2e8f9f7 | 132 | while (!spi_writeable(obj)); |
<> | 144:ef7eb2e8f9f7 | 133 | obj->spi->D = value; |
<> | 144:ef7eb2e8f9f7 | 134 | } |