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mbed-dev/drivers/SPI.cpp@1:d0dfbce63a89, 2017-02-24 (annotated)

Committer:
elmot
Date:
Fri Feb 24 21:13:56 2017 +0000
Revision:
1:d0dfbce63a89
Ready-to-copy

Who changed what in which revision?

UserRevisionLine numberNew contents of line
elmot 1:d0dfbce63a89 1 /* mbed Microcontroller Library
elmot 1:d0dfbce63a89 2 * Copyright (c) 2006-2013 ARM Limited
elmot 1:d0dfbce63a89 3 *
elmot 1:d0dfbce63a89 4 * Licensed under the Apache License, Version 2.0 (the "License");
elmot 1:d0dfbce63a89 5 * you may not use this file except in compliance with the License.
elmot 1:d0dfbce63a89 6 * You may obtain a copy of the License at
elmot 1:d0dfbce63a89 7 *
elmot 1:d0dfbce63a89 8 * http://www.apache.org/licenses/LICENSE-2.0
elmot 1:d0dfbce63a89 9 *
elmot 1:d0dfbce63a89 10 * Unless required by applicable law or agreed to in writing, software
elmot 1:d0dfbce63a89 11 * distributed under the License is distributed on an "AS IS" BASIS,
elmot 1:d0dfbce63a89 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
elmot 1:d0dfbce63a89 13 * See the License for the specific language governing permissions and
elmot 1:d0dfbce63a89 14 * limitations under the License.
elmot 1:d0dfbce63a89 15 */
elmot 1:d0dfbce63a89 16 #include "drivers/SPI.h"
elmot 1:d0dfbce63a89 17 #include "platform/critical.h"
elmot 1:d0dfbce63a89 18
elmot 1:d0dfbce63a89 19 #if DEVICE_SPI
elmot 1:d0dfbce63a89 20
elmot 1:d0dfbce63a89 21 namespace mbed {
elmot 1:d0dfbce63a89 22
elmot 1:d0dfbce63a89 23 #if DEVICE_SPI_ASYNCH && TRANSACTION_QUEUE_SIZE_SPI
elmot 1:d0dfbce63a89 24 CircularBuffer<Transaction<SPI>, TRANSACTION_QUEUE_SIZE_SPI> SPI::_transaction_buffer;
elmot 1:d0dfbce63a89 25 #endif
elmot 1:d0dfbce63a89 26
elmot 1:d0dfbce63a89 27 SPI::SPI(PinName mosi, PinName miso, PinName sclk, PinName ssel) :
elmot 1:d0dfbce63a89 28 _spi(),
elmot 1:d0dfbce63a89 29 #if DEVICE_SPI_ASYNCH
elmot 1:d0dfbce63a89 30 _irq(this),
elmot 1:d0dfbce63a89 31 _usage(DMA_USAGE_NEVER),
elmot 1:d0dfbce63a89 32 #endif
elmot 1:d0dfbce63a89 33 _bits(8),
elmot 1:d0dfbce63a89 34 _mode(0),
elmot 1:d0dfbce63a89 35 _hz(1000000) {
elmot 1:d0dfbce63a89 36 // No lock needed in the constructor
elmot 1:d0dfbce63a89 37
elmot 1:d0dfbce63a89 38 spi_init(&_spi, mosi, miso, sclk, ssel);
elmot 1:d0dfbce63a89 39 aquire();
elmot 1:d0dfbce63a89 40 }
elmot 1:d0dfbce63a89 41
elmot 1:d0dfbce63a89 42 void SPI::format(int bits, int mode) {
elmot 1:d0dfbce63a89 43 lock();
elmot 1:d0dfbce63a89 44 _bits = bits;
elmot 1:d0dfbce63a89 45 _mode = mode;
elmot 1:d0dfbce63a89 46 SPI::_owner = NULL; // Not that elegant, but works. rmeyer
elmot 1:d0dfbce63a89 47 aquire();
elmot 1:d0dfbce63a89 48 unlock();
elmot 1:d0dfbce63a89 49 }
elmot 1:d0dfbce63a89 50
elmot 1:d0dfbce63a89 51 void SPI::frequency(int hz) {
elmot 1:d0dfbce63a89 52 lock();
elmot 1:d0dfbce63a89 53 _hz = hz;
elmot 1:d0dfbce63a89 54 SPI::_owner = NULL; // Not that elegant, but works. rmeyer
elmot 1:d0dfbce63a89 55 aquire();
elmot 1:d0dfbce63a89 56 unlock();
elmot 1:d0dfbce63a89 57 }
elmot 1:d0dfbce63a89 58
elmot 1:d0dfbce63a89 59 SPI* SPI::_owner = NULL;
elmot 1:d0dfbce63a89 60 SingletonPtr<PlatformMutex> SPI::_mutex;
elmot 1:d0dfbce63a89 61
elmot 1:d0dfbce63a89 62 // ignore the fact there are multiple physical spis, and always update if it wasnt us last
elmot 1:d0dfbce63a89 63 void SPI::aquire() {
elmot 1:d0dfbce63a89 64 lock();
elmot 1:d0dfbce63a89 65 if (_owner != this) {
elmot 1:d0dfbce63a89 66 spi_format(&_spi, _bits, _mode, 0);
elmot 1:d0dfbce63a89 67 spi_frequency(&_spi, _hz);
elmot 1:d0dfbce63a89 68 _owner = this;
elmot 1:d0dfbce63a89 69 }
elmot 1:d0dfbce63a89 70 unlock();
elmot 1:d0dfbce63a89 71 }
elmot 1:d0dfbce63a89 72
elmot 1:d0dfbce63a89 73 int SPI::write(int value) {
elmot 1:d0dfbce63a89 74 lock();
elmot 1:d0dfbce63a89 75 aquire();
elmot 1:d0dfbce63a89 76 int ret = spi_master_write(&_spi, value);
elmot 1:d0dfbce63a89 77 unlock();
elmot 1:d0dfbce63a89 78 return ret;
elmot 1:d0dfbce63a89 79 }
elmot 1:d0dfbce63a89 80
elmot 1:d0dfbce63a89 81 void SPI::lock() {
elmot 1:d0dfbce63a89 82 _mutex->lock();
elmot 1:d0dfbce63a89 83 }
elmot 1:d0dfbce63a89 84
elmot 1:d0dfbce63a89 85 void SPI::unlock() {
elmot 1:d0dfbce63a89 86 _mutex->unlock();
elmot 1:d0dfbce63a89 87 }
elmot 1:d0dfbce63a89 88
elmot 1:d0dfbce63a89 89 #if DEVICE_SPI_ASYNCH
elmot 1:d0dfbce63a89 90
elmot 1:d0dfbce63a89 91 int SPI::transfer(const void *tx_buffer, int tx_length, void *rx_buffer, int rx_length, unsigned char bit_width, const event_callback_t& callback, int event)
elmot 1:d0dfbce63a89 92 {
elmot 1:d0dfbce63a89 93 if (spi_active(&_spi)) {
elmot 1:d0dfbce63a89 94 return queue_transfer(tx_buffer, tx_length, rx_buffer, rx_length, bit_width, callback, event);
elmot 1:d0dfbce63a89 95 }
elmot 1:d0dfbce63a89 96 start_transfer(tx_buffer, tx_length, rx_buffer, rx_length, bit_width, callback, event);
elmot 1:d0dfbce63a89 97 return 0;
elmot 1:d0dfbce63a89 98 }
elmot 1:d0dfbce63a89 99
elmot 1:d0dfbce63a89 100 void SPI::abort_transfer()
elmot 1:d0dfbce63a89 101 {
elmot 1:d0dfbce63a89 102 spi_abort_asynch(&_spi);
elmot 1:d0dfbce63a89 103 #if TRANSACTION_QUEUE_SIZE_SPI
elmot 1:d0dfbce63a89 104 dequeue_transaction();
elmot 1:d0dfbce63a89 105 #endif
elmot 1:d0dfbce63a89 106 }
elmot 1:d0dfbce63a89 107
elmot 1:d0dfbce63a89 108
elmot 1:d0dfbce63a89 109 void SPI::clear_transfer_buffer()
elmot 1:d0dfbce63a89 110 {
elmot 1:d0dfbce63a89 111 #if TRANSACTION_QUEUE_SIZE_SPI
elmot 1:d0dfbce63a89 112 _transaction_buffer.reset();
elmot 1:d0dfbce63a89 113 #endif
elmot 1:d0dfbce63a89 114 }
elmot 1:d0dfbce63a89 115
elmot 1:d0dfbce63a89 116 void SPI::abort_all_transfers()
elmot 1:d0dfbce63a89 117 {
elmot 1:d0dfbce63a89 118 clear_transfer_buffer();
elmot 1:d0dfbce63a89 119 abort_transfer();
elmot 1:d0dfbce63a89 120 }
elmot 1:d0dfbce63a89 121
elmot 1:d0dfbce63a89 122 int SPI::set_dma_usage(DMAUsage usage)
elmot 1:d0dfbce63a89 123 {
elmot 1:d0dfbce63a89 124 if (spi_active(&_spi)) {
elmot 1:d0dfbce63a89 125 return -1;
elmot 1:d0dfbce63a89 126 }
elmot 1:d0dfbce63a89 127 _usage = usage;
elmot 1:d0dfbce63a89 128 return 0;
elmot 1:d0dfbce63a89 129 }
elmot 1:d0dfbce63a89 130
elmot 1:d0dfbce63a89 131 int SPI::queue_transfer(const void *tx_buffer, int tx_length, void *rx_buffer, int rx_length, unsigned char bit_width, const event_callback_t& callback, int event)
elmot 1:d0dfbce63a89 132 {
elmot 1:d0dfbce63a89 133 #if TRANSACTION_QUEUE_SIZE_SPI
elmot 1:d0dfbce63a89 134 transaction_t t;
elmot 1:d0dfbce63a89 135
elmot 1:d0dfbce63a89 136 t.tx_buffer = const_cast<void *>(tx_buffer);
elmot 1:d0dfbce63a89 137 t.tx_length = tx_length;
elmot 1:d0dfbce63a89 138 t.rx_buffer = rx_buffer;
elmot 1:d0dfbce63a89 139 t.rx_length = rx_length;
elmot 1:d0dfbce63a89 140 t.event = event;
elmot 1:d0dfbce63a89 141 t.callback = callback;
elmot 1:d0dfbce63a89 142 t.width = bit_width;
elmot 1:d0dfbce63a89 143 Transaction<SPI> transaction(this, t);
elmot 1:d0dfbce63a89 144 if (_transaction_buffer.full()) {
elmot 1:d0dfbce63a89 145 return -1; // the buffer is full
elmot 1:d0dfbce63a89 146 } else {
elmot 1:d0dfbce63a89 147 core_util_critical_section_enter();
elmot 1:d0dfbce63a89 148 _transaction_buffer.push(transaction);
elmot 1:d0dfbce63a89 149 if (!spi_active(&_spi)) {
elmot 1:d0dfbce63a89 150 dequeue_transaction();
elmot 1:d0dfbce63a89 151 }
elmot 1:d0dfbce63a89 152 core_util_critical_section_exit();
elmot 1:d0dfbce63a89 153 return 0;
elmot 1:d0dfbce63a89 154 }
elmot 1:d0dfbce63a89 155 #else
elmot 1:d0dfbce63a89 156 return -1;
elmot 1:d0dfbce63a89 157 #endif
elmot 1:d0dfbce63a89 158 }
elmot 1:d0dfbce63a89 159
elmot 1:d0dfbce63a89 160 void SPI::start_transfer(const void *tx_buffer, int tx_length, void *rx_buffer, int rx_length, unsigned char bit_width, const event_callback_t& callback, int event)
elmot 1:d0dfbce63a89 161 {
elmot 1:d0dfbce63a89 162 aquire();
elmot 1:d0dfbce63a89 163 _callback = callback;
elmot 1:d0dfbce63a89 164 _irq.callback(&SPI::irq_handler_asynch);
elmot 1:d0dfbce63a89 165 spi_master_transfer(&_spi, tx_buffer, tx_length, rx_buffer, rx_length, bit_width, _irq.entry(), event , _usage);
elmot 1:d0dfbce63a89 166 }
elmot 1:d0dfbce63a89 167
elmot 1:d0dfbce63a89 168 #if TRANSACTION_QUEUE_SIZE_SPI
elmot 1:d0dfbce63a89 169
elmot 1:d0dfbce63a89 170 void SPI::start_transaction(transaction_t *data)
elmot 1:d0dfbce63a89 171 {
elmot 1:d0dfbce63a89 172 start_transfer(data->tx_buffer, data->tx_length, data->rx_buffer, data->rx_length, data->width, data->callback, data->event);
elmot 1:d0dfbce63a89 173 }
elmot 1:d0dfbce63a89 174
elmot 1:d0dfbce63a89 175 void SPI::dequeue_transaction()
elmot 1:d0dfbce63a89 176 {
elmot 1:d0dfbce63a89 177 Transaction<SPI> t;
elmot 1:d0dfbce63a89 178 if (_transaction_buffer.pop(t)) {
elmot 1:d0dfbce63a89 179 SPI* obj = t.get_object();
elmot 1:d0dfbce63a89 180 transaction_t* data = t.get_transaction();
elmot 1:d0dfbce63a89 181 obj->start_transaction(data);
elmot 1:d0dfbce63a89 182 }
elmot 1:d0dfbce63a89 183 }
elmot 1:d0dfbce63a89 184
elmot 1:d0dfbce63a89 185 #endif
elmot 1:d0dfbce63a89 186
elmot 1:d0dfbce63a89 187 void SPI::irq_handler_asynch(void)
elmot 1:d0dfbce63a89 188 {
elmot 1:d0dfbce63a89 189 int event = spi_irq_handler_asynch(&_spi);
elmot 1:d0dfbce63a89 190 if (_callback && (event & SPI_EVENT_ALL)) {
elmot 1:d0dfbce63a89 191 _callback.call(event & SPI_EVENT_ALL);
elmot 1:d0dfbce63a89 192 }
elmot 1:d0dfbce63a89 193 #if TRANSACTION_QUEUE_SIZE_SPI
elmot 1:d0dfbce63a89 194 if (event & (SPI_EVENT_ALL | SPI_EVENT_INTERNAL_TRANSFER_COMPLETE)) {
elmot 1:d0dfbce63a89 195 // SPI peripheral is free (event happend), dequeue transaction
elmot 1:d0dfbce63a89 196 dequeue_transaction();
elmot 1:d0dfbce63a89 197 }
elmot 1:d0dfbce63a89 198 #endif
elmot 1:d0dfbce63a89 199 }
elmot 1:d0dfbce63a89 200
elmot 1:d0dfbce63a89 201 #endif
elmot 1:d0dfbce63a89 202
elmot 1:d0dfbce63a89 203 } // namespace mbed
elmot 1:d0dfbce63a89 204
elmot 1:d0dfbce63a89 205 #endif